Re: [RE-wrenches] How much Li battery?

[la...@starlightsolar.com]

Mark,

It is conceivable to use Li-ion without protection. To do so you must ALWAYS 
guarantee that you will not over charge, over current, over discharge or charge 
frozen cells…ever. This is a 0 tolerance rule. In a RE system, how can you be 
100% sure? 

Modest rates is not the issue. It’s already difficult to overcurrent the GBS 
cells. Over voltage a cell just once and you can cause damage or possibly fire. 
Similarly, if you over discharge a cell just once you can damage it and may 
cause a future fire while charging it normally.

Cell balancers only reduce a small amount of current on a single cell that is 
becoming saturated. It won’t stop over voltage.

To my knowledge there is no safe way to have a Li battery system without 
BMS/EMS unless you are always in control of charge/discharge events. 

Scold…now that you know, yes, consider yourself scolded.

Larry Crutcher
Starlight Solar Power Systems



On May 26, 2020, at 12:24 PM, Mark Frye  wrote:

Thanks Larry,

I am familiar with GBS cells. Would you scold me too badly if I told you my 
thought that with modest discharge rates and on the charge side, with cell 
balancers installed, and limiting the charge current to 15A, one doesn't really 
need the BMS for the 60AH pack? 

On 5/26/2020 10:47 AM, la...@starlightsolar.com 
<mailto:la...@starlightsolar.com> wrote:
> Hi Mark,
> 
> One of the many benefits of Li-ion is the ability to provide much higher 
> continuous current than any comparable size LA battery.  
> 
> You don’t need more than 2kWh (40Ah) and want to know the smallest battery 
> you can use. To directly answer your question: A 60AH Elite Power Solutions 
> (GBS cells) battery bank @ 48V has about 3 kWh of energy storage. This is a 
> tiny battery bank, just 20”L x 11”W and weighs only 80 pounds. However, it 
> can provide a whopping 9kW (3C) continuous output and up to 31kW momentarily! 
> Thats much more than you will likely ever use. 
> 
> Though hard to imagine, this will work with your inverter. We have built 
> several 3kW inverter systems @ 12V with a single 100AH battery for starting 
> heavy loads like air compressors and air conditioners. No problem. Whether 
> this is the “best practice” will require more discussion. Let me know if you 
> need more detailed help as we have many years experience with Li-ion battery 
> systems.
> 
> Larry Crutcher
> Starlight Solar Power Systems
> 
> From: Mark Frye mailto:ma...@berkeleysolar.com>>
> Subject: [RE-wrenches] How much Li battery?
> 
> In the way back machine I remember being at a product roll out meeting 
> for the brand new Outback FX inverter. I asked the engineer, what was 
> the smallest battery bank that could be connected to the inverter. He 
> said on the fly that probably you would want the battery to "weight" at 
> least as much as the inverter. I thought that was a great answer.
> 
> Fast forward, with a 4000w Outback Radian, AC coupled with 2000w of PV, 
> what is the smallest Li battery I would want for stable operation?
> 
> My loads don't really need more than 40ah of capacity.
> 
> What is the latest best practice on this?
> 
> Thanks.
> 

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Re: [RE-wrenches] How much Li battery?

[Mark Frye]

Thanks Larry,

I am familiar with GBS cells. Would you scold me too badly if I told you 
my thought that with modest discharge rates and on the charge side, with 
cell balancers installed, and limiting the charge current to 15A, one 
doesn't really need the BMS for the 60AH pack?


On 5/26/2020 10:47 AM, la...@starlightsolar.com wrote:

Hi Mark,

One of the many benefits of Li-ion is the ability to provide much 
higher continuous current than any comparable size LA battery.


You don’t need more than 2kWh (40Ah) and want to know the smallest 
battery you can use. To directly answer your question: A 60AH Elite 
Power Solutions (GBS cells) battery bank @ 48V has about 3 kWh of 
energy storage. This is a tiny battery bank, just 20”L x 11”W and 
weighs only 80 pounds. However, it can provide a whopping 9kW (3C) 
continuous output and up to 31kW momentarily! Thats much more than you 
will likely ever use.


Though hard to imagine, this will work with your inverter. We have 
built several 3kW inverter systems @ 12V with a single 100AH battery 
for starting heavy loads like air compressors and air conditioners. No 
problem. Whether this is the “best practice” will require more 
discussion. Let me know if you need more detailed help as we have many 
years experience with Li-ion battery systems.


Larry Crutcher
Starlight Solar Power Systems

From: Mark Frye mailto:ma...@berkeleysolar.com>>
Subject: [RE-wrenches] How much Li battery?

In the way back machine I remember being at a product roll out meeting
for the brand new Outback FX inverter. I asked the engineer, what was
the smallest battery bank that could be connected to the inverter. He
said on the fly that probably you would want the battery to "weight" at
least as much as the inverter. I thought that was a great answer.

Fast forward, with a 4000w Outback Radian, AC coupled with 2000w of PV,
what is the smallest Li battery I would want for stable operation?

My loads don't really need more than 40ah of capacity.

What is the latest best practice on this?

Thanks.


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Re: [RE-wrenches] How much Li battery?

[la...@starlightsolar.com]

Hi Mark,

One of the many benefits of Li-ion is the ability to provide much higher 
continuous current than any comparable size LA battery.  

You don’t need more than 2kWh (40Ah) and want to know the smallest battery you 
can use. To directly answer your question: A 60AH Elite Power Solutions (GBS 
cells) battery bank @ 48V has about 3 kWh of energy storage. This is a tiny 
battery bank, just 20”L x 11”W and weighs only 80 pounds. However, it can 
provide a whopping 9kW (3C) continuous output and up to 31kW momentarily! Thats 
much more than you will likely ever use. 

Though hard to imagine, this will work with your inverter. We have built 
several 3kW inverter systems @ 12V with a single 100AH battery for starting 
heavy loads like air compressors and air conditioners. No problem. Whether this 
is the “best practice” will require more discussion. Let me know if you need 
more detailed help as we have many years experience with Li-ion battery systems.

Larry Crutcher
Starlight Solar Power Systems

From: Mark Frye mailto:ma...@berkeleysolar.com>>
Subject: [RE-wrenches] How much Li battery?

In the way back machine I remember being at a product roll out meeting 
for the brand new Outback FX inverter. I asked the engineer, what was 
the smallest battery bank that could be connected to the inverter. He 
said on the fly that probably you would want the battery to "weight" at 
least as much as the inverter. I thought that was a great answer.

Fast forward, with a 4000w Outback Radian, AC coupled with 2000w of PV, 
what is the smallest Li battery I would want for stable operation?

My loads don't really need more than 40ah of capacity.

What is the latest best practice on this?

Thanks.

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Re: [RE-wrenches] How much Li battery?

[Mark Frye]

Humm...suppose I wanted for myself some lead calcium flooded batteries, 
about 100 AH at 48 V, anyone have an idea of a good vendor?


On 5/26/2020 3:12 AM, drake.chamber...@redwoodalliance.org wrote:


I would use Concorde VRLA batteries. They can take a very fast charge. 
In certain conditions they can charge at C X 5 instead of C/5.




---


On 2020-05-25 18:13, Jay wrote:


You might check out discover batteries.
I'm a big fan of companies they make their equipment, they do, one of 
the very few in the lithium world.
And while the original question specifically asked about Lithium, 
what you're requiring is perfectly suited for VRLA float service 
batteries.

Long life, much lower cost.
Jay
Peltz power.

On May 25, 2020, at 2:37 PM, Dave Angelini Offgrid Solar 
 wrote:


Jay knows about these and I won't name them just because I use 
them.  They are the perfect size for most offgrid and scalable.


I have a client in Texas who left them for 14 months off, and maybe 
they lost 1%. The best part of them for me, is all a client has to 
do is enter the date in the system control panel and all of the rest 
is done. True plug and play. Built by a company that has made 
locomotive batteries for decades. I asked them Jay on linkedin.  He 
said do what you want with Soc. Don't worry about any of that. Just 
know that we have you covered. Below is from their latest webinar.


For a solar installation to pass final inspection, the batteries 
must have been tested and approved to UL 1973. Not just the cell but 
the battery. So, before making a final selection, verify that the 
battery selection you make has you covered. These LiFePO_4 
 batteries meet this certification, so you can be confident that 
your customers batteries are safe and pass inspection. Our 
commitment to safety, reliability and certification also delivers 
the following.


  * Safe and Maintenance Free
  * Sophisticated High Current BMS
  * Field Serviceable BMS
  * IP 55 Rated
  * IEC 62133 Safety
  * UL 1973 Safety Certified
  * UN 38.3 Transport Certified


  
*Dave Angelini Offgrid Solar "we go where powerlines don't" 
http://members.sti.net/offgridsolar/ e-mail offgridso...@sti.net 
 text 209 813 0060*


On Sun, 24 May 2020 21:05:06 -0700, Jerry Shafer 
 wrote:


It may take a little bit as it wrapped up just over 2 years ago,
most of the research stayed at the lab. I do recall V2 did not
survive the cycling test, it was unable to restart from 99% dod.
There is no substitute for a multi-level battery management
structure when it comes to Li tech. I have priced simplify dirt
to keys and it cost more then Blue did and required more space.
There was another one that came in near the end and was built in
what appeared to be a 66" tall chemical storage cabinet just to
make it fire rated, maybe it's just me but batteries that can
catch fire may not be the best choice but hey I'm funny like
that. Anyone installing any batteries needs to read the very
fine print that talks about "what to do in case of" and that can
be a deciding factor right there.
Way back when all FLA's had to be in a pan to catch the acid
before it did damage, that was 20 years ago by now it should be
safer not more dangerous.

On Sun, May 24, 2020, 8:36 PM jay mailto:jay.pe...@gmail.com>> wrote:

HI Jerry,
Most impressive.
Would you be willing to tell us which ones didn't meet this
test, if not publicly, then off list?
thanks
jay


On May 24, 2020, at 3:23 PM, Jerry Shafer
mailto:jerrysgarag...@gmail.com>> wrote:

Wrenches
Again not all batteries are the same, Chemistry,
recharge rate or intelligence of the BMS, l have
personally tested Blue planet batteries, l have let them
sit at 100% SOC for 10 weeks, ran them at 30% SOC for 6
months, l have performed 100% to 0% cycling up to 4
times a day. This is the same tests l ran on a variety
of Li tech batteries and BluePlanet is the only one that
survived this testing. It's ore then spec sheets and
cost, it comes down to success or failure, personally l
like success and being able to pass or fail batteries
without having my customers pay the price is a good
thing. Blue Planet has 8000 cycles life and a 15 year
warranty at 70% compare that to anything out there but
again that's just me.

On Sun, May 24, 2020, 1:32 PM Darryl Thayer
mailto:darylsol...@gmail.com>>
wrote:

I have spoken with a li battery
researcher. Do not charge over 85% of battery full
charge voltage and they will last over 25 years. 
 But go above or below bottom and trouble

On Sun, May 24, 2020, 10:27 AM Jay
 

Re: [RE-wrenches] How much Li battery?

[drake . chamberlin]

I would use Concorde VRLA batteries. They can take a very fast charge.
In certain conditions they can charge at C X 5 instead of C/5. 


---

On 2020-05-25 18:13, Jay wrote:

You might check out discover batteries.  
I'm a big fan of companies they make their equipment, they do, one of the very few in the lithium world.  

And while the original question specifically asked about Lithium, what you're requiring is perfectly suited for VRLA float service batteries.  
Long life, much lower cost.  

Jay 

Peltz power.  


On May 25, 2020, at 2:37 PM, Dave Angelini Offgrid Solar  
wrote:


Jay knows about these and I won't name them just because I use them.  They are the perfect size for most offgrid and scalable. 

I have a client in Texas who left them for 14 months off, and maybe they lost 1%. The best part of them for me, is all a client has to do is enter the date in the system control panel and all of the rest is done. True plug and play. Built by a company that has made locomotive batteries for decades. I asked them Jay on linkedin.  He said do what you want with Soc. Don't worry about any of that. Just know that we have you covered. Below is from their latest webinar. 

For a solar installation to pass final inspection, the batteries must have been tested and approved to UL 1973. Not just the cell but the battery. So, before making a final selection, verify that the battery selection you make has you covered. These LiFePO4 batteries meet this certification, so you can be confident that your customers batteries are safe and pass inspection. Our commitment to safety, reliability and certification also delivers the following. 


* Safe and Maintenance Free
* Sophisticated High Current BMS
* Field Serviceable BMS
* IP 55 Rated
* IEC 62133 Safety
* UL 1973 Safety Certified
* UN 38.3 Transport Certified

Dave Angelini Offgrid Solar
"we go where powerlines don't"
http://members.sti.net/offgridsolar/
e-mail  offgridso...@sti.net
text 209 813 0060

On Sun, 24 May 2020 21:05:06 -0700, Jerry Shafer  wrote: 
It may take a little bit as it wrapped up just over 2 years ago, most of the research stayed at the lab. I do recall V2 did not survive the cycling test, it was unable to restart from 99% dod. There is no substitute for a multi-level battery management structure when it comes to Li tech. I have priced simplify dirt to keys and it cost more then Blue did and required more space. There was another one that came in near the end and was built in what appeared to be a 66" tall chemical storage cabinet just to make it fire rated, maybe it's just me but batteries that can catch fire may not be the best choice but hey I'm funny like that. Anyone installing any batteries needs to read the very fine print that talks about "what to do in case of" and that can be a deciding factor right there. 
Way back when all FLA's had to be in a pan to catch the acid before it did damage, that was 20 years ago by now it should be safer not more dangerous. 

On Sun, May 24, 2020, 8:36 PM jay  wrote: 
HI Jerry, 

Most impressive. 

Would you be willing to tell us which ones didn't meet this test, if not publicly, then off list? 

thanks 

jay 

On May 24, 2020, at 3:23 PM, Jerry Shafer  wrote: 

Wrenches 
Again not all batteries are the same, Chemistry, recharge rate or intelligence of the BMS, l have personally tested Blue planet batteries, l have let them sit at 100% SOC for 10 weeks, ran them at 30% SOC for 6 months, l have performed 100% to 0% cycling up to 4 times a day. This is the same tests l ran on a variety of Li tech batteries and BluePlanet is the only one that survived this testing. It's ore then spec sheets and cost, it comes down to success or failure, personally l like success and being able to pass or fail batteries without having my customers pay the price is a good thing. Blue Planet has 8000 cycles life and a 15 year warranty at 70% compare that to anything out there but again that's just me. 

On Sun, May 24, 2020, 1:32 PM Darryl Thayer  wrote: 
I have spoken with a li battery 
researcher. Do not charge over 85% of battery full charge voltage and they will last over 25 years.   But go above or below bottom and trouble 

On Sun, May 24, 2020, 10:27 AM Jay  wrote: 

One question I have for those more versed than me in lithium is, I'm under the impression that having a lithium battery in float for years isn't good for it. Or at the very least it has to be cycled with some regularity.  

I'd like to hear data on that 

Thx 
Jay 

Peltz power.  


On May 23, 2020, at 10:08 PM, Ray  wrote:

I suggest starting with a very simple look at the continuous output rating of the battery and match that to the inverter continuous rating. This ends up with quite a bit more battery than you might think at first.  However, if the customer paid the big bucks for a battery backup system, they should at least get enough battery to operate the inverter at its rated power.  Anything less, I would consider poor design.  The same goes for lea

Re: [RE-wrenches] How much Li battery?

[Jay]

You might check out discover batteries. 
I’m a big fan of companies they make their equipment, they do, one of the very 
few in the lithium world. 


And while the original question specifically asked about Lithium, what you’re 
requiring is perfectly suited for VRLA float service batteries. 
Long life, much lower cost. 

Jay

Peltz power. 




> On May 25, 2020, at 2:37 PM, Dave Angelini Offgrid Solar 
>  wrote:
> 
> 
> Jay knows about these and I won't name them just because I use them.  They 
> are the perfect size for most offgrid and scalable.
> 
> I have a client in Texas who left them for 14 months off, and maybe they lost 
> 1%. The best part of them for me, is all a client has to do is enter the date 
> in the system control panel and all of the rest is done. True plug and play. 
> Built by a company that has made locomotive batteries for decades. I asked 
> them Jay on linkedin.  He said do what you want with Soc. Don't worry about 
> any of that. Just know that we have you covered. Below is from their latest 
> webinar.
> 
> For a solar installation to pass final inspection, the batteries must have 
> been tested and approved to UL 1973. Not just the cell but the battery. So, 
> before making a final selection, verify that the battery selection you make 
> has you covered. These LiFePO4 batteries meet this certification, so you can 
> be confident that your customers batteries are safe and pass inspection. Our 
> commitment to safety, reliability and certification also delivers the 
> following.
> 
> Safe and Maintenance Free
> Sophisticated High Current BMS
> Field Serviceable BMS
> IP 55 Rated
> IEC 62133 Safety
> UL 1973 Safety Certified
> UN 38.3 Transport Certified
>  
> 
>  
> Dave Angelini Offgrid Solar
> "we go where powerlines don't"
> http://members.sti.net/offgridsolar/
> e-mail  offgridso...@sti.net
> text 209 813 0060
>> On Sun, 24 May 2020 21:05:06 -0700, Jerry Shafer  
>> wrote:
>> 
>> It may take a little bit as it wrapped up just over 2 years ago, most of the 
>> research stayed at the lab. I do recall V2 did not survive the cycling test, 
>> it was unable to restart from 99% dod. There is no substitute for a 
>> multi-level battery management structure when it comes to Li tech. I have 
>> priced simplify dirt to keys and it cost more then Blue did and required 
>> more space. There was another one that came in near the end and was built in 
>> what appeared to be a 66" tall chemical storage cabinet just to make it fire 
>> rated, maybe it's just me but batteries that can catch fire may not be the 
>> best choice but hey I'm funny like that. Anyone installing any batteries 
>> needs to read the very fine print that talks about "what to do in case of" 
>> and that can be a deciding factor right there.
>> Way back when all FLA's had to be in a pan to catch the acid before it did 
>> damage, that was 20 years ago by now it should be safer not more dangerous.
>> 
>>> On Sun, May 24, 2020, 8:36 PM jay  wrote:
>>> HI Jerry,
>>>  
>>> Most impressive.
>>>  
>>> Would you be willing to tell us which ones didn't meet this test, if not 
>>> publicly, then off list?
>>>  
>>> thanks
>>>  
>>> jay
>>>  
>>> 
>>> 
 On May 24, 2020, at 3:23 PM, Jerry Shafer  wrote:
 
 Wrenches
 Again not all batteries are the same, Chemistry, recharge rate or 
 intelligence of the BMS, l have personally tested Blue planet batteries, l 
 have let them sit at 100% SOC for 10 weeks, ran them at 30% SOC for 6 
 months, l have performed 100% to 0% cycling up to 4 times a day. This is 
 the same tests l ran on a variety of Li tech batteries and BluePlanet is 
 the only one that survived this testing. It's ore then spec sheets and 
 cost, it comes down to success or failure, personally l like success and 
 being able to pass or fail batteries without having my customers pay the 
 price is a good thing. Blue Planet has 8000 cycles life and a 15 year 
 warranty at 70% compare that to anything out there but again that's just 
 me.
 
> On Sun, May 24, 2020, 1:32 PM Darryl Thayer  wrote:
> I have spoken with a li battery
> researcher. Do not charge over 85% of battery full charge voltage and 
> they will last over 25 years.   But go above or below bottom and trouble
> 
>> On Sun, May 24, 2020, 10:27 AM Jay  wrote:
>> One question I have for those more versed than me in lithium is, I'm 
>> under the impression that having a lithium battery in float for years 
>> isn't good for it. Or at the very least it has to be cycled with some 
>> regularity. 
>>  
>> I'd like to hear data on that
>>  
>> Thx
>> Jay
>>  
>> Peltz power. 
>>  
>>  
>>  
>>  
>> 
>>> On May 23, 2020, at 10:08 PM, Ray  wrote:
>>> 
>>> I suggest starting with a very simple look at the continuous output 
>>> rating of the battery and match that to the inverter continuous rating. 
>>> This e

Re: [RE-wrenches] How much Li battery?

[Dave Angelini Offgrid Solar]

Jay knows about these and I won't name them just because I use them.
They are the perfect size for most offgrid and scalable. 

I have a client
in Texas who left them for 14 months off, and maybe they lost 1%. The best
part of them for me, is all a client has to do is enter the date in the
system control panel and all of the rest is done. True plug and play. Built
by a company that has made locomotive batteries for decades. I asked them
Jay on linkedin. He said do what you want with Soc. Don't worry about any
of that. Just know that we have you covered. Below is from their latest
webinar. 

For a solar installation to pass final inspection, the batteries
must have been tested and approved to UL 1973. Not just the cell but the
battery. So, before making a final selection, verify that the battery
selection you make has you covered. These LiFePO4 batteries meet this
certification, so you can be confident that your customers batteries are
safe and pass inspection. Our commitment to safety, reliability and
certification also delivers the following. 

* Safe and Maintenance Free

* Sophisticated High Current BMS
* Field Serviceable BMS
* IP 55
Rated
* IEC 62133 Safety
* UL 1973 Safety Certified
* UN 38.3
Transport Certified

Dave Angelini Offgrid Solar
"we go where powerlines
don't"
http://members.sti.net/offgridsolar/ [1]
e-mail offgridso...@sti.net
[2]
text 209 813 0060

On Sun, 24 May 2020 21:05:06 -0700, Jerry Shafer 
wrote:  It may take a little bit as it wrapped up just over 2 years ago,
most of the research stayed at the lab. I do recall V2 did not survive the
cycling test, it was unable to restart from 99% dod. There is no substitute
for a multi-level battery management structure when it comes to Li tech. I
have priced simplify dirt to keys and it cost more then Blue did and
required more space. There was another one that came in near the end and
was built in what appeared to be a 66" tall chemical storage cabinet just
to make it fire rated, maybe it's just me but batteries that can catch fire
may not be the best choice but hey I'm funny like that. Anyone installing
any batteries needs to read the very fine print that talks about "what to
do in case of" and that can be a deciding factor right there. Way back when
all FLA's had to be in a pan to catch the acid before it did damage, that
was 20 years ago by now it should be safer not more dangerous.  
  On Sun,
May 24, 2020, 8:36 PM jay  wrote:  HI Jerry,   Most impressive.   Would you
be willing to tell us which ones didn't meet this test, if not publicly,
then off list?   thanks   jay   

  On May 24, 2020, at 3:23 PM, Jerry
Shafer  wrote: 
  Wrenches Again not all batteries are the same, Chemistry,
recharge rate or intelligence of the BMS, l have personally tested Blue
planet batteries, l have let them sit at 100% SOC for 10 weeks, ran them at
30% SOC for 6 months, l have performed 100% to 0% cycling up to 4 times a
day. This is the same tests l ran on a variety of Li tech batteries and
BluePlanet is the only one that survived this testing. It's ore then spec
sheets and cost, it comes down to success or failure, personally l like
success and being able to pass or fail batteries without having my
customers pay the price is a good thing. Blue Planet has 8000 cycles life
and a 15 year warranty at 70% compare that to anything out there but again
that's just me.  
  On Sun, May 24, 2020, 1:32 PM Darryl Thayer  wrote:  I
have spoken with a li battery researcher. Do not charge over 85% of battery
full charge voltage and they will last over 25 years. But go above or below
bottom and trouble  
  On Sun, May 24, 2020, 10:27 AM Jay  wrote:   One
question I have for those more versed than me in lithium is, I'm under the
impression that having a lithium battery in float for years isn't good for
it. Or at the very least it has to be cycled with some regularity.I'd
like to hear data on that   Thx Jay   Peltz power.  
 On May 23,
2020, at 10:08 PM, Ray  wrote:

I suggest starting with a very simple look
at the continuous output rating of the battery and match that to the
inverter continuous rating. This ends up with quite a bit more battery than
you might think at first. However, if the customer paid the big bucks for a
battery backup system, they should at least get enough battery to operate
the inverter at its rated power. Anything less, I would consider poor
design. The same goes for lead acid batteries, they just don't work well,
even on grid, when the battery is undersized. Even lead acid batteries have
maximum current output ratings that should at least be matched to the
inverter rating.  

If you WERE going to under size the battery, then you
should keep it safe by reducing the size of the inverter battery breaker as
well. I know this "micro battery for GTB" is becoming a trend, but it
doesn't mean its right.  
Ray Walters
Remote Solar
303 505-8760
 On 5/23/20
5:48 PM, Mick Abraham wrote:  Gre

Re: [RE-wrenches] How much Li battery?

[Jerry Shafer]

It may take a little bit as it wrapped up just over 2 years ago, most of
the research stayed at the lab. I do recall V2 did not survive the cycling
test, it was unable to restart from 99% dod. There is no substitute for a
multi-level battery management structure when it comes to Li tech. I have
priced simplify dirt to keys and it cost more then Blue did and required
more space. There was another one that came in near the end and was built
in what appeared to be a 66" tall chemical storage cabinet just to make it
fire rated, maybe it's just me but batteries that can catch fire may not be
the best choice but hey I'm funny like that. Anyone installing any
batteries needs to read the very fine print that talks about "what to do in
case of" and that can be a deciding factor right there.
Way back when all FLA's had to be in a pan to catch the acid before it did
damage, that was 20 years ago by now it should be safer not more dangerous.

On Sun, May 24, 2020, 8:36 PM jay  wrote:

> HI Jerry,
>
> Most impressive.
>
> Would you be willing to tell us which ones didn’t meet this test, if not
> publicly, then off list?
>
> thanks
>
> jay
>
>
>
> On May 24, 2020, at 3:23 PM, Jerry Shafer 
> wrote:
>
> Wrenches
> Again not all batteries are the same, Chemistry, recharge rate or
> intelligence of the BMS, l have personally tested Blue planet batteries, l
> have let them sit at 100% SOC for 10 weeks, ran them at 30% SOC for 6
> months, l have performed 100% to 0% cycling up to 4 times a day. This is
> the same tests l ran on a variety of Li tech batteries and BluePlanet is
> the only one that survived this testing. It's ore then spec sheets and
> cost, it comes down to success or failure, personally l like success and
> being able to pass or fail batteries without having my customers pay the
> price is a good thing. Blue Planet has 8000 cycles life and a 15 year
> warranty at 70% compare that to anything out there but again that's just me.
>
> On Sun, May 24, 2020, 1:32 PM Darryl Thayer  wrote:
>
>> I have spoken with a li battery
>> researcher. Do not charge over 85% of battery full charge voltage and
>> they will last over 25 years.   But go above or below bottom and trouble
>>
>> On Sun, May 24, 2020, 10:27 AM Jay  wrote:
>>
>>> One question I have for those more versed than me in lithium is, I’m
>>> under the impression that having a lithium battery in float for years isn’t
>>> good for it. Or at the very least it has to be cycled with some regularity.
>>>
>>> I’d like to hear data on that
>>>
>>> Thx
>>> Jay
>>>
>>> Peltz power.
>>>
>>>
>>>
>>>
>>>
>>> On May 23, 2020, at 10:08 PM, Ray  wrote:
>>>
>>> 
>>>
>>> I suggest starting with a very simple look at the continuous output
>>> rating of the battery and match that to the inverter continuous rating.
>>> This ends up with quite a bit more battery than you might think at first.
>>> However, if the customer paid the big bucks for a battery backup system,
>>> they should at least get enough battery to operate the inverter at its
>>> rated power.  Anything less, I would consider poor design.  The same goes
>>> for lead acid batteries, they just don't work well, even on grid, when the
>>> battery is undersized.  Even lead acid batteries have maximum current
>>> output ratings that should at least be matched to the inverter rating.
>>>
>>> If you WERE going to under size the battery, then you should keep it
>>> safe by reducing the size of the inverter battery breaker as well.   I know
>>> this "micro battery for GTB" is becoming a trend, but it doesn't mean its
>>> right.
>>>
>>> Ray Walters
>>> Remote Solar
>>> 303 505-8760
>>>
>>> On 5/23/20 5:48 PM, Mick Abraham wrote:
>>>
>>> Greetings, All~ Mark Frye had asked:  "...with a 4000w Outback Radian,
>>> AC coupled with 2000w of PV, what is the smallest Li battery I would want
>>> for stable operation?"
>>>
>>> Mick's reply: In the lithium arena, one often finds the ratings in
>>> kilowatt-hours rather than in amp-hours. This is an easy conversion for us
>>> energy nerds to make, so below I'm mainly using watts & watt-hours with
>>> occasional conversions to amp-hours.
>>>
>>> I suggest that you start with the spec sheet (of whichever brand lithium
>>> battery is on your radar), & see what the manufacturer says about
>>> "allowable rate of recharge". You may find that C/2 is an acceptable rate
>>> with several manufacturers, Mark--much faster than what we're accustomed to
>>> with typical lead-acid batteries. Let's assume:
>>>
>>> * ...that your AC coupled PV array crests around 1800 watts to the
>>> battery when there are no loads
>>> * ...that the battery is below 100% state of charge, and
>>> * ...that the solar conditions are optimal.
>>>
>>> Let's further assume that those conditions represent your battery's
>>> highest energy rate in either direction.
>>>
>>> 1800w X two hours = 3,600 watt-hours dividing by 48v nominal = 75
>>> amp-hours in the above hypothetical situation.
>>>
>>> ++
>>

Re: [RE-wrenches] How much Li battery?

[jay]

HI Jerry,

Most impressive.

Would you be willing to tell us which ones didn’t meet this test, if not 
publicly, then off list?

thanks

jay



> On May 24, 2020, at 3:23 PM, Jerry Shafer  wrote:
> 
> Wrenches
> Again not all batteries are the same, Chemistry, recharge rate or 
> intelligence of the BMS, l have personally tested Blue planet batteries, l 
> have let them sit at 100% SOC for 10 weeks, ran them at 30% SOC for 6 months, 
> l have performed 100% to 0% cycling up to 4 times a day. This is the same 
> tests l ran on a variety of Li tech batteries and BluePlanet is the only one 
> that survived this testing. It's ore then spec sheets and cost, it comes down 
> to success or failure, personally l like success and being able to pass or 
> fail batteries without having my customers pay the price is a good thing. 
> Blue Planet has 8000 cycles life and a 15 year warranty at 70% compare that 
> to anything out there but again that's just me.
> 
> On Sun, May 24, 2020, 1:32 PM Darryl Thayer  > wrote:
> I have spoken with a li battery
> researcher. Do not charge over 85% of battery full charge voltage and they 
> will last over 25 years.   But go above or below bottom and trouble
> 
> On Sun, May 24, 2020, 10:27 AM Jay  > wrote:
> One question I have for those more versed than me in lithium is, I’m under 
> the impression that having a lithium battery in float for years isn’t good 
> for it. Or at the very least it has to be cycled with some regularity. 
> 
> I’d like to hear data on that
> 
> Thx
> Jay
> 
> Peltz power. 
> 
> 
> 
> 
> 
>> On May 23, 2020, at 10:08 PM, Ray > > wrote:
>> 
>> 
>> I suggest starting with a very simple look at the continuous output rating 
>> of the battery and match that to the inverter continuous rating. This ends 
>> up with quite a bit more battery than you might think at first.  However, if 
>> the customer paid the big bucks for a battery backup system, they should at 
>> least get enough battery to operate the inverter at its rated power.  
>> Anything less, I would consider poor design.  The same goes for lead acid 
>> batteries, they just don't work well, even on grid, when the battery is 
>> undersized.  Even lead acid batteries have maximum current output ratings 
>> that should at least be matched to the inverter rating.   
>> 
>> If you WERE going to under size the battery, then you should keep it safe by 
>> reducing the size of the inverter battery breaker as well.   I know this 
>> "micro battery for GTB" is becoming a trend, but it doesn't mean its right. 
>> 
>> Ray Walters
>> Remote Solar
>> 303 505-8760
>> On 5/23/20 5:48 PM, Mick Abraham wrote:
>>> Greetings, All~ Mark Frye had asked:  "...with a 4000w Outback Radian, AC 
>>> coupled with 2000w of PV, what is the smallest Li battery I would want for 
>>> stable operation?"  
>>> 
>>> Mick's reply: In the lithium arena, one often finds the ratings in 
>>> kilowatt-hours rather than in amp-hours. This is an easy conversion for us 
>>> energy nerds to make, so below I'm mainly using watts & watt-hours with 
>>> occasional conversions to amp-hours.
>>> 
>>> I suggest that you start with the spec sheet (of whichever brand lithium 
>>> battery is on your radar), & see what the manufacturer says about 
>>> "allowable rate of recharge". You may find that C/2 is an acceptable rate 
>>> with several manufacturers, Mark--much faster than what we're accustomed to 
>>> with typical lead-acid batteries. Let's assume:
>>> 
>>> * ...that your AC coupled PV array crests around 1800 watts to the battery 
>>> when there are no loads
>>> * ...that the battery is below 100% state of charge, and
>>> * ...that the solar conditions are optimal. 
>>> 
>>> Let's further assume that those conditions represent your battery's highest 
>>> energy rate in either direction. 
>>> 
>>> 1800w X two hours = 3,600 watt-hours dividing by 48v nominal = 75 amp-hours 
>>> in the above hypothetical situation. 
>>> 
>>> ++
>>> 
>>> The rate at which a battery can receive energy is (usually) also the rate 
>>> at which it can comfortably deplete, so let's briefly look at the flip 
>>> side: Assuming the battery mfr. wants the watt-hours to be no less than two 
>>> times the maximum wattage, a 3600 watt-hour (C/2) battery should not be 
>>> depleted faster than 1800 watts. Your 4kW Radian, Mark, could exceed that 
>>> if the loads demand it--& maybe your loads don't. Motor starting surges 
>>> should probably be part of the thinking & it wouldn't hurt to ask the 
>>> mfr.'s opinion about short term surges which briefly deplete the battery 
>>> faster than the hypothetical two hour rate.
>>> 
>>> By approaching this question based on the battery manufacturer do's & 
>>> don'ts, one improves the chance of getting warranty coverage should it 
>>> later be needed. "What the large print giveth, the fine print taketh away." 
>>> 
>>> The Wrenc

Re: [RE-wrenches] How much Li battery?

[Jerry Shafer]

If you have a resale number that should be fine, at least it has been with
me, they ask before ordering, do you need a contact person

On Sun, May 24, 2020, 4:23 PM Dave Angelini Offgrid Solar <
offgridso...@sti.net> wrote:

> Hi Jerry,
>
> When I looked at Blue Planet I had to pay the sales tax as none the normal
> distributors would carry Blue Planet. Has that changed please?
>
> *Dave Angelini Offgrid Solar
> "we go where powerlines don't"
> http://members.sti.net/offgridsolar/ 
> e-mail  offgridso...@sti.net 
> text 209 813 0060*
>
> On Sun, 24 May 2020 15:23:50 -0700, Jerry Shafer 
> wrote:
>
> Wrenches
> Again not all batteries are the same, Chemistry, recharge rate or
> intelligence of the BMS, l have personally tested Blue planet batteries, l
> have let them sit at 100% SOC for 10 weeks, ran them at 30% SOC for 6
> months, l have performed 100% to 0% cycling up to 4 times a day. This is
> the same tests l ran on a variety of Li tech batteries and BluePlanet is
> the only one that survived this testing. It's ore then spec sheets and
> cost, it comes down to success or failure, personally l like success and
> being able to pass or fail batteries without having my customers pay the
> price is a good thing. Blue Planet has 8000 cycles life and a 15 year
> warranty at 70% compare that to anything out there but again that's just me.
>
> On Sun, May 24, 2020, 1:32 PM Darryl Thayer  wrote:
>
>> I have spoken with a li battery
>> researcher. Do not charge over 85% of battery full charge voltage and
>> they will last over 25 years.   But go above or below bottom and trouble
>>
>> On Sun, May 24, 2020, 10:27 AM Jay  wrote:
>>
>>> One question I have for those more versed than me in lithium is, I'm
>>> under the impression that having a lithium battery in float for years isn't
>>> good for it. Or at the very least it has to be cycled with some regularity.
>>>
>>> I'd like to hear data on that
>>>
>>> Thx
>>> Jay
>>>
>>> Peltz power.
>>>
>>>
>>>
>>>
>>>
>>> On May 23, 2020, at 10:08 PM, Ray  wrote:
>>>
>>> I suggest starting with a very simple look at the continuous output
>>> rating of the battery and match that to the inverter continuous rating.
>>> This ends up with quite a bit more battery than you might think at first.
>>> However, if the customer paid the big bucks for a battery backup system,
>>> they should at least get enough battery to operate the inverter at its
>>> rated power.  Anything less, I would consider poor design.  The same goes
>>> for lead acid batteries, they just don't work well, even on grid, when the
>>> battery is undersized.  Even lead acid batteries have maximum current
>>> output ratings that should at least be matched to the inverter rating.
>>>
>>> If you WERE going to under size the battery, then you should keep it
>>> safe by reducing the size of the inverter battery breaker as well.   I know
>>> this "micro battery for GTB" is becoming a trend, but it doesn't mean its
>>> right.
>>>
>>> Ray Walters
>>> Remote Solar
>>> 303 505-8760
>>>
>>> On 5/23/20 5:48 PM, Mick Abraham wrote:
>>>
>>> Greetings, All~ Mark Frye had asked:  "...with a 4000w Outback Radian,
>>> AC coupled with 2000w of PV, what is the smallest Li battery I would want
>>> for stable operation?"
>>>
>>> Mick's reply: In the lithium arena, one often finds the ratings in
>>> kilowatt-hours rather than in amp-hours. This is an easy conversion for us
>>> energy nerds to make, so below I'm mainly using watts & watt-hours with
>>> occasional conversions to amp-hours.
>>>
>>> I suggest that you start with the spec sheet (of whichever brand lithium
>>> battery is on your radar), & see what the manufacturer says about
>>> "allowable rate of recharge". You may find that C/2 is an acceptable rate
>>> with several manufacturers, Mark--much faster than what we're accustomed to
>>> with typical lead-acid batteries. Let's assume:
>>>
>>> * ...that your AC coupled PV array crests around 1800 watts to the
>>> battery when there are no loads
>>> * ...that the battery is below 100% state of charge, and
>>> * ...that the solar conditions are optimal.
>>>
>>> Let's further assume that those conditions represent your battery's
>>> highest energy rate in either direction.
>>>
>>> 1800w X two hours = 3,600 watt-hours dividing by 48v nominal = 75
>>> amp-hours in the above hypothetical situation.
>>>
>>> ++
>>>
>>> The rate at which a battery can receive energy is (usually) also the
>>> rate at which it can comfortably deplete, so let's briefly look at the flip
>>> side: Assuming the battery mfr. wants the watt-hours to be no less than two
>>> times the maximum wattage, a 3600 watt-hour (C/2) battery should not be
>>> depleted faster than 1800 watts. Your 4kW Radian, Mark, could exceed that
>>> if the loads demand it--& maybe your loads don't. Motor starting surges
>>> should probably be part of the thinking & it wouldn't hurt to ask the
>>> mfr.'s opinion about short ter

Re: [RE-wrenches] How much Li battery?

[Dave Angelini Offgrid Solar]

Hi Jerry, 

When I looked at Blue Planet I had to pay the sales tax as
none the normal distributors would carry Blue Planet. Has that changed
please?   
Dave Angelini Offgrid Solar
"we go where powerlines
don't"
http://members.sti.net/offgridsolar/ [1]
e-mail offgridso...@sti.net
[2]
text 209 813 0060

On Sun, 24 May 2020 15:23:50 -0700, Jerry Shafer 
wrote:  Wrenches Again not all batteries are the same, Chemistry, recharge
rate or intelligence of the BMS, l have personally tested Blue planet
batteries, l have let them sit at 100% SOC for 10 weeks, ran them at 30%
SOC for 6 months, l have performed 100% to 0% cycling up to 4 times a day.
This is the same tests l ran on a variety of Li tech batteries and
BluePlanet is the only one that survived this testing. It's ore then spec
sheets and cost, it comes down to success or failure, personally l like
success and being able to pass or fail batteries without having my
customers pay the price is a good thing. Blue Planet has 8000 cycles life
and a 15 year warranty at 70% compare that to anything out there but again
that's just me.  
  On Sun, May 24, 2020, 1:32 PM Darryl Thayer  wrote:  I
have spoken with a li battery researcher. Do not charge over 85% of battery
full charge voltage and they will last over 25 years. But go above or below
bottom and trouble  
  On Sun, May 24, 2020, 10:27 AM Jay  wrote:   One
question I have for those more versed than me in lithium is, I'm under the
impression that having a lithium battery in float for years isn't good for
it. Or at the very least it has to be cycled with some regularity.I'd
like to hear data on that   Thx Jay   Peltz power.  
 On May 23,
2020, at 10:08 PM, Ray  wrote:

I suggest starting with a very simple look
at the continuous output rating of the battery and match that to the
inverter continuous rating. This ends up with quite a bit more battery than
you might think at first. However, if the customer paid the big bucks for a
battery backup system, they should at least get enough battery to operate
the inverter at its rated power. Anything less, I would consider poor
design. The same goes for lead acid batteries, they just don't work well,
even on grid, when the battery is undersized. Even lead acid batteries have
maximum current output ratings that should at least be matched to the
inverter rating.  

If you WERE going to under size the battery, then you
should keep it safe by reducing the size of the inverter battery breaker as
well. I know this "micro battery for GTB" is becoming a trend, but it
doesn't mean its right.  
Ray Walters
Remote Solar
303 505-8760
 On 5/23/20
5:48 PM, Mick Abraham wrote:  Greetings, All~ Mark Frye had asked: "...with
a 4000w Outback Radian, AC coupled with 2000w of PV, what is the smallest
Li battery I would want for stable operation?"   Mick's reply: In the
lithium arena, one often finds the ratings in kilowatt-hours rather than in
amp-hours. This is an easy conversion for us energy nerds to make, so below
I'm mainly using watts & watt-hours with occasional conversions to
amp-hours.   I suggest that you start with the spec sheet (of whichever
brand lithium battery is on your radar), & see what the manufacturer says
about "allowable rate of recharge". You may find that C/2 is an acceptable
rate with several manufacturers, Mark--much faster than what we're
accustomed to with typical lead-acid batteries. Let's assume:   * ...that
your AC coupled PV array crests around 1800 watts to the battery when there
are no loads * ...that the battery is below 100% state of charge, and *
...that the solar conditions are optimal.Let's further assume that
those conditions represent your battery's highest energy rate in either
direction.1800w X two hours = 3,600 watt-hours dividing by 48v nominal
= 75 amp-hours in the above hypothetical situation.   
++   The rate at which a battery can receive
energy is (usually) also the rate at which it can comfortably deplete, so
let's briefly look at the flip side: Assuming the battery mfr. wants the
watt-hours to be no less than two times the maximum wattage, a 3600
watt-hour (C/2) battery should not be depleted faster than 1800 watts. Your
4kW Radian, Mark, could exceed that if the loads demand it--& maybe your
loads don't. Motor starting surges should probably be part of the thinking
& it wouldn't hurt to ask the mfr.'s opinion about short term surges which
briefly deplete the battery faster than the hypothetical two hour rate.  
By approaching this question based on the battery manufacturer do's ">ᐧ


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Re: [RE-wrenches] How much Li battery?

[Jerry Shafer]

Wrenches
Again not all batteries are the same, Chemistry, recharge rate or
intelligence of the BMS, l have personally tested Blue planet batteries, l
have let them sit at 100% SOC for 10 weeks, ran them at 30% SOC for 6
months, l have performed 100% to 0% cycling up to 4 times a day. This is
the same tests l ran on a variety of Li tech batteries and BluePlanet is
the only one that survived this testing. It's ore then spec sheets and
cost, it comes down to success or failure, personally l like success and
being able to pass or fail batteries without having my customers pay the
price is a good thing. Blue Planet has 8000 cycles life and a 15 year
warranty at 70% compare that to anything out there but again that's just me.

On Sun, May 24, 2020, 1:32 PM Darryl Thayer  wrote:

> I have spoken with a li battery
> researcher. Do not charge over 85% of battery full charge voltage and they
> will last over 25 years.   But go above or below bottom and trouble
>
> On Sun, May 24, 2020, 10:27 AM Jay  wrote:
>
>> One question I have for those more versed than me in lithium is, I’m
>> under the impression that having a lithium battery in float for years isn’t
>> good for it. Or at the very least it has to be cycled with some regularity.
>>
>> I’d like to hear data on that
>>
>> Thx
>> Jay
>>
>> Peltz power.
>>
>>
>>
>>
>>
>> On May 23, 2020, at 10:08 PM, Ray  wrote:
>>
>> 
>>
>> I suggest starting with a very simple look at the continuous output
>> rating of the battery and match that to the inverter continuous rating.
>> This ends up with quite a bit more battery than you might think at first.
>> However, if the customer paid the big bucks for a battery backup system,
>> they should at least get enough battery to operate the inverter at its
>> rated power.  Anything less, I would consider poor design.  The same goes
>> for lead acid batteries, they just don't work well, even on grid, when the
>> battery is undersized.  Even lead acid batteries have maximum current
>> output ratings that should at least be matched to the inverter rating.
>>
>> If you WERE going to under size the battery, then you should keep it safe
>> by reducing the size of the inverter battery breaker as well.   I know this
>> "micro battery for GTB" is becoming a trend, but it doesn't mean its right.
>>
>> Ray Walters
>> Remote Solar
>> 303 505-8760
>>
>> On 5/23/20 5:48 PM, Mick Abraham wrote:
>>
>> Greetings, All~ Mark Frye had asked:  "...with a 4000w Outback Radian, AC
>> coupled with 2000w of PV, what is the smallest Li battery I would want for
>> stable operation?"
>>
>> Mick's reply: In the lithium arena, one often finds the ratings in
>> kilowatt-hours rather than in amp-hours. This is an easy conversion for us
>> energy nerds to make, so below I'm mainly using watts & watt-hours with
>> occasional conversions to amp-hours.
>>
>> I suggest that you start with the spec sheet (of whichever brand lithium
>> battery is on your radar), & see what the manufacturer says about
>> "allowable rate of recharge". You may find that C/2 is an acceptable rate
>> with several manufacturers, Mark--much faster than what we're accustomed to
>> with typical lead-acid batteries. Let's assume:
>>
>> * ...that your AC coupled PV array crests around 1800 watts to the
>> battery when there are no loads
>> * ...that the battery is below 100% state of charge, and
>> * ...that the solar conditions are optimal.
>>
>> Let's further assume that those conditions represent your battery's
>> highest energy rate in either direction.
>>
>> 1800w X two hours = 3,600 watt-hours dividing by 48v nominal = 75
>> amp-hours in the above hypothetical situation.
>>
>> ++
>>
>> The rate at which a battery can receive energy is (usually) also the rate
>> at which it can comfortably deplete, so let's briefly look at the flip
>> side: Assuming the battery mfr. wants the watt-hours to be no less than two
>> times the maximum wattage, a 3600 watt-hour (C/2) battery should not be
>> depleted faster than 1800 watts. Your 4kW Radian, Mark, could exceed that
>> if the loads demand it--& maybe your loads don't. Motor starting surges
>> should probably be part of the thinking & it wouldn't hurt to ask the
>> mfr.'s opinion about short term surges which briefly deplete the battery
>> faster than the hypothetical two hour rate.
>>
>> By approaching this question based on the battery manufacturer do's &
>> don'ts, one improves the chance of getting warranty coverage should it
>> later be needed. "What the large print giveth, the fine print taketh away."
>>
>> The Wrench List is the Bomb!
>>
>> Mick Abraham, Proprietor
>> www.abrahamsolar.com
>>
>> Landline: 970-731-4675
>> Cell phone or for text messaging: 970-946-6584
>> ᐧ
>>
>> ___
>> List sponsored by Redwood Alliance
>>
>> List Address: RE-wrenches@lists.re-wrenches.org
>>
>> Change listserver email address & 
>> settings:http://lists.re-wrenches.org/options.cgi/re-wrenches

Re: [RE-wrenches] How much Li battery?

[Dave Angelini Offgrid Solar]

Another parameter to look at for long life is max charge and discharge
current. We killed the LG RESU 10 48vdc battery here with an XW+. XW has a
140 amp charger and 6.8kw was too much. That ended the Conext Bridge with
LG. I think that is why Discover AES is doing well as they were designed
for XW and Radians. 

The LG failed in dead short and the bms was good
still. Big Ouch! Glad I was home  
Dave Angelini Offgrid Solar
"we go
where powerlines don't"
http://members.sti.net/offgridsolar/ [1]
e-mail
offgridso...@sti.net [2]
text 209 813 0060

On Sun, 24 May 2020 15:31:51
-0500, Darryl Thayer  wrote:  I have spoken with a li battery researcher.
Do not charge over 85% of battery full charge voltage and they will last
over 25 years. But go above or below bottom and trouble  
  On Sun, May 24,
2020, 10:27 AM Jay  wrote:   One question I have for those more versed than
me in lithium is, I'm under the impression that having a lithium battery in
float for years isn't good for it. Or at the very least it has to be cycled
with some regularity.I'd like to hear data on that   Thx Jay   Peltz
power.  
 On May 23, 2020, at 10:08 PM, Ray  wrote:

I suggest
starting with a very simple look at the continuous output rating of the
battery and match that to the inverter continuous rating. This ends up with
quite a bit more battery than you might think at first. However, if the
customer paid the big bucks for a battery backup system, they should at
least get enough battery to operate the inverter at its rated power.
Anything less, I would consider poor design. The same goes for lead acid
batteries, they just don't work well, even on grid, when the battery is
undersized. Even lead acid batteries have maximum current output ratings
that should at least be matched to the inverter rating.  

If you WERE
going to under size the battery, then you should keep it safe by reducing
the size of the inverter battery breaker as well. I know this "micro
battery for GTB" is becoming a trend, but it doesn't mean its right.  
Ray
Walters
Remote Solar
303 505-8760
 On 5/23/20 5:48 PM, Mick Abraham wrote: 
Greetings, All~ Mark Frye had asked: "...with a 4000w Outback Radian, AC
coupled with 2000w of PV, what is the smallest Li battery I would want for
stable operation?"   Mick's reply: In the lithium arena, one often finds
the ratings in kilowatt-hours rather than in amp-hours. This is an easy
conversion for us energy nerds to make, so below I'm mainly using watts &
watt-hours with occasional conversions to amp-hours.   I suggest that you
start with the spec sheet (of whichever brand lithium battery is on your
radar), & see what the manufacturer says about "allowable rate of
recharge". You may find that C/2 is an acceptable rate with several
manufacturers, Mark--much faster than what we're accustomed to with typical
lead-acid batteries. Let's assume:   * ...that your AC coupled PV array
crests around 1800 watts to the battery when there are no loads * ...that
the battery is below 100% state of charge, and * ...that the solar
conditions are optimal.Let's further assume that those conditions
represent your battery's highest energy rate in either direction.1800w
X two hours = 3,600 watt-hours dividing by 48v nominal = 75 amp-hours in
the above hypothetical situation.++   The
rate at which a battery can receive energy is (usually) also the rate at
which it can comfortably deplete, so let's briefly look at the flip side:
Assuming the battery mfr. wants the watt-hours to be no less than two times
the maximum wattage, a 3600 watt-hour (C/2) battery should not be depleted
faster than 1800 watts. Your 4kW Radian, Mark, could exceed that if the
loads demand it--& maybe your loads don't. Motor starting surges should
probably be part of the thinking & it wouldn't hurt to ask the mfr.'s
opinion about short term surges which briefly deplete the battery faster
than the hypothetical two hour rate.   By approaching this question based
on the battery manufacturer do's ">ᐧ


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Re: [RE-wrenches] How much Li battery?

[Darryl Thayer]

I have spoken with a li battery
researcher. Do not charge over 85% of battery full charge voltage and they
will last over 25 years.   But go above or below bottom and trouble

On Sun, May 24, 2020, 10:27 AM Jay  wrote:

> One question I have for those more versed than me in lithium is, I’m under
> the impression that having a lithium battery in float for years isn’t good
> for it. Or at the very least it has to be cycled with some regularity.
>
> I’d like to hear data on that
>
> Thx
> Jay
>
> Peltz power.
>
>
>
>
>
> On May 23, 2020, at 10:08 PM, Ray  wrote:
>
> 
>
> I suggest starting with a very simple look at the continuous output rating
> of the battery and match that to the inverter continuous rating. This ends
> up with quite a bit more battery than you might think at first.  However,
> if the customer paid the big bucks for a battery backup system, they should
> at least get enough battery to operate the inverter at its rated power.
> Anything less, I would consider poor design.  The same goes for lead acid
> batteries, they just don't work well, even on grid, when the battery is
> undersized.  Even lead acid batteries have maximum current output ratings
> that should at least be matched to the inverter rating.
>
> If you WERE going to under size the battery, then you should keep it safe
> by reducing the size of the inverter battery breaker as well.   I know this
> "micro battery for GTB" is becoming a trend, but it doesn't mean its right.
>
> Ray Walters
> Remote Solar
> 303 505-8760
>
> On 5/23/20 5:48 PM, Mick Abraham wrote:
>
> Greetings, All~ Mark Frye had asked:  "...with a 4000w Outback Radian, AC
> coupled with 2000w of PV, what is the smallest Li battery I would want for
> stable operation?"
>
> Mick's reply: In the lithium arena, one often finds the ratings in
> kilowatt-hours rather than in amp-hours. This is an easy conversion for us
> energy nerds to make, so below I'm mainly using watts & watt-hours with
> occasional conversions to amp-hours.
>
> I suggest that you start with the spec sheet (of whichever brand lithium
> battery is on your radar), & see what the manufacturer says about
> "allowable rate of recharge". You may find that C/2 is an acceptable rate
> with several manufacturers, Mark--much faster than what we're accustomed to
> with typical lead-acid batteries. Let's assume:
>
> * ...that your AC coupled PV array crests around 1800 watts to the battery
> when there are no loads
> * ...that the battery is below 100% state of charge, and
> * ...that the solar conditions are optimal.
>
> Let's further assume that those conditions represent your battery's
> highest energy rate in either direction.
>
> 1800w X two hours = 3,600 watt-hours dividing by 48v nominal = 75
> amp-hours in the above hypothetical situation.
>
> ++
>
> The rate at which a battery can receive energy is (usually) also the rate
> at which it can comfortably deplete, so let's briefly look at the flip
> side: Assuming the battery mfr. wants the watt-hours to be no less than two
> times the maximum wattage, a 3600 watt-hour (C/2) battery should not be
> depleted faster than 1800 watts. Your 4kW Radian, Mark, could exceed that
> if the loads demand it--& maybe your loads don't. Motor starting surges
> should probably be part of the thinking & it wouldn't hurt to ask the
> mfr.'s opinion about short term surges which briefly deplete the battery
> faster than the hypothetical two hour rate.
>
> By approaching this question based on the battery manufacturer do's &
> don'ts, one improves the chance of getting warranty coverage should it
> later be needed. "What the large print giveth, the fine print taketh away."
>
> The Wrench List is the Bomb!
>
> Mick Abraham, Proprietor
> www.abrahamsolar.com
>
> Landline: 970-731-4675
> Cell phone or for text messaging: 970-946-6584
> ᐧ
>
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Re: [RE-wrenches] How much Li battery?

[Jerry Shafer]

Jay, Wrenches
It depends on the chemistry manganese, cobalt tend to require cycling,
phosphate not as much. Every brand has its sweet spot regarding cycling and
cycle life
Jerry


On Sun, May 24, 2020, 10:56 AM Jay  wrote:

> One question I have for those more versed than me in lithium is, I’m under
> the impression that having a lithium battery in float for years isn’t good
> for it. Or at the very least it has to be cycled with some regularity.
>
> I’d like to hear data on that
>
> Thx
> Jay
>
> Peltz power.
>
>
>
>
>
> On May 23, 2020, at 10:08 PM, Ray  wrote:
>
> 
>
> I suggest starting with a very simple look at the continuous output rating
> of the battery and match that to the inverter continuous rating. This ends
> up with quite a bit more battery than you might think at first.  However,
> if the customer paid the big bucks for a battery backup system, they should
> at least get enough battery to operate the inverter at its rated power.
> Anything less, I would consider poor design.  The same goes for lead acid
> batteries, they just don't work well, even on grid, when the battery is
> undersized.  Even lead acid batteries have maximum current output ratings
> that should at least be matched to the inverter rating.
>
> If you WERE going to under size the battery, then you should keep it safe
> by reducing the size of the inverter battery breaker as well.   I know this
> "micro battery for GTB" is becoming a trend, but it doesn't mean its right.
>
> Ray Walters
> Remote Solar
> 303 505-8760
>
> On 5/23/20 5:48 PM, Mick Abraham wrote:
>
> Greetings, All~ Mark Frye had asked:  "...with a 4000w Outback Radian, AC
> coupled with 2000w of PV, what is the smallest Li battery I would want for
> stable operation?"
>
> Mick's reply: In the lithium arena, one often finds the ratings in
> kilowatt-hours rather than in amp-hours. This is an easy conversion for us
> energy nerds to make, so below I'm mainly using watts & watt-hours with
> occasional conversions to amp-hours.
>
> I suggest that you start with the spec sheet (of whichever brand lithium
> battery is on your radar), & see what the manufacturer says about
> "allowable rate of recharge". You may find that C/2 is an acceptable rate
> with several manufacturers, Mark--much faster than what we're accustomed to
> with typical lead-acid batteries. Let's assume:
>
> * ...that your AC coupled PV array crests around 1800 watts to the battery
> when there are no loads
> * ...that the battery is below 100% state of charge, and
> * ...that the solar conditions are optimal.
>
> Let's further assume that those conditions represent your battery's
> highest energy rate in either direction.
>
> 1800w X two hours = 3,600 watt-hours dividing by 48v nominal = 75
> amp-hours in the above hypothetical situation.
>
> ++
>
> The rate at which a battery can receive energy is (usually) also the rate
> at which it can comfortably deplete, so let's briefly look at the flip
> side: Assuming the battery mfr. wants the watt-hours to be no less than two
> times the maximum wattage, a 3600 watt-hour (C/2) battery should not be
> depleted faster than 1800 watts. Your 4kW Radian, Mark, could exceed that
> if the loads demand it--& maybe your loads don't. Motor starting surges
> should probably be part of the thinking & it wouldn't hurt to ask the
> mfr.'s opinion about short term surges which briefly deplete the battery
> faster than the hypothetical two hour rate.
>
> By approaching this question based on the battery manufacturer do's &
> don'ts, one improves the chance of getting warranty coverage should it
> later be needed. "What the large print giveth, the fine print taketh away."
>
> The Wrench List is the Bomb!
>
> Mick Abraham, Proprietor
> www.abrahamsolar.com
>
> Landline: 970-731-4675
> Cell phone or for text messaging: 970-946-6584
> ᐧ
>
> ___
> List sponsored by Redwood Alliance
>
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Re: [RE-wrenches] How much Li battery?

[Dave Angelini Offgrid Solar]

When I mix a lead acid system and a lithium it often is done to use up
the life of the lead acid system. In this case, the lithium is just left
off and hopefully gets used and tested monthly or so. In winter offgrid,
the LFP gets used in bad weather and increases the days you can run in bad
weather without a generator. 

Doing this is a challenge as both batteries
have different set-points and I have never been able to use the same DC
buss for my clients. This DC bus is where the solar is. What I do is use a
seperate inverter for the lithium and charge it from the AC bus of the lead
acid inverter. 

It sounds complicated but it is just a flick of the AC
bypass in the power distribution panel of an XW or Radian. Another breaker
turns on the charger in the lithium inv/chg. Eventually the old lead acid
will go away. The clients love this as it gets them a completely
independent power system. They can do the same thing later and just have
two LFP banks/inverters.  

Dave Angelini Offgrid Solar
"we go where
powerlines don't"
http://members.sti.net/offgridsolar/ [1]
e-mail
offgridso...@sti.net [2]
text 209 813 0060

On Sun, 24 May 2020 07:15:53
-0700, Jay  wrote:  One question I have for those more versed than me in
lithium is, I'm under the impression that having a lithium battery in float
for years isn't good for it. Or at the very least it has to be cycled with
some regularity.I'd like to hear data on that   Thx Jay   Peltz power. 
   
 On May 23, 2020, at 10:08 PM, Ray  wrote:

I suggest starting
with a very simple look at the continuous output rating of the battery and
match that to the inverter continuous rating. This ends up with quite a bit
more battery than you might think at first. However, if the customer paid
the big bucks for a battery backup system, they should at least get enough
battery to operate the inverter at its rated power. Anything less, I would
consider poor design. The same goes for lead acid batteries, they just
don't work well, even on grid, when the battery is undersized. Even lead
acid batteries have maximum current output ratings that should at least be
matched to the inverter rating.  

If you WERE going to under size the
battery, then you should keep it safe by reducing the size of the inverter
battery breaker as well. I know this "micro battery for GTB" is becoming a
trend, but it doesn't mean its right.  
Ray Walters
Remote Solar
303
505-8760
 On 5/23/20 5:48 PM, Mick Abraham wrote:  Greetings, All~ Mark
Frye had asked: "...with a 4000w Outback Radian, AC coupled with 2000w of
PV, what is the smallest Li battery I would want for stable operation?"  
Mick's reply: In the lithium arena, one often finds the ratings in
kilowatt-hours rather than in amp-hours. This is an easy conversion for us
energy nerds to make, so below I'm mainly using watts & watt-hours with
occasional conversions to amp-hours.   I suggest that you start with the
spec sheet (of whichever brand lithium battery is on your radar), & see
what the manufacturer says about "allowable rate of recharge". You may find
that C/2 is an acceptable rate with several manufacturers, Mark--much
faster than what we're accustomed to with typical lead-acid batteries.
Let's assume:   * ...that your AC coupled PV array crests around 1800 watts
to the battery when there are no loads * ...that the battery is below 100%
state of charge, and * ...that the solar conditions are optimal.Let's
further assume that those conditions represent your battery's highest
energy rate in either direction.1800w X two hours = 3,600 watt-hours
dividing by 48v nominal = 75 amp-hours in the above hypothetical situation.
  ++   The rate at which a battery can receive
energy is (usually) also the rate at which it can comfortably deplete, so
let's briefly look at the flip side: Assuming the battery mfr. wants the
watt-hours to be no less than two times the maximum wattage, a 3600
watt-hour (C/2) battery should not be depleted faster than 1800 watts. Your
4kW Radian, Mark, could exceed that if the loads demand it--& maybe your
loads don't. Motor starting surges should probably be part of the thinking
& it wouldn't hurt to ask the mfr.'s opinion about short term surges which
briefly deplete the battery faster than the hypothetical two hour rate.  
By approaching this question based on the battery manufacturer do's ">ᐧ


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Re: [RE-wrenches] How much Li battery?

[Dave Angelini Offgrid Solar]

My experience is that is really is about the cycles and the design life
of the battery. Both will give you an idea of how long it should last at
the amount of power you need. 

It is a poor design to over cycle and just
as poor to use so little power that the system life is exceeded without
using the power you paid for. The HALT testing gives an idea of life and
many battery makers do not tell you about accelerated testing.  

So, the
good part is they are fine with partial Soc, but the float it forever in
grid tie may not be good. I think they need to be exercised if they are to
be depended on. I have not seen anyone saying that. A good question Jay


Dave Angelini Offgrid Solar
"we go where powerlines
don't"
http://members.sti.net/offgridsolar/ [1]
e-mail offgridso...@sti.net
[2]
text 209 813 0060

On Sun, 24 May 2020 07:15:53 -0700, Jay  wrote:  One
question I have for those more versed than me in lithium is, I'm under the
impression that having a lithium battery in float for years isn't good for
it. Or at the very least it has to be cycled with some regularity.I'd
like to hear data on that   Thx Jay   Peltz power.  
 On May 23,
2020, at 10:08 PM, Ray  wrote:

I suggest starting with a very simple look
at the continuous output rating of the battery and match that to the
inverter continuous rating. This ends up with quite a bit more battery than
you might think at first. However, if the customer paid the big bucks for a
battery backup system, they should at least get enough battery to operate
the inverter at its rated power. Anything less, I would consider poor
design. The same goes for lead acid batteries, they just don't work well,
even on grid, when the battery is undersized. Even lead acid batteries have
maximum current output ratings that should at least be matched to the
inverter rating.  

If you WERE going to under size the battery, then you
should keep it safe by reducing the size of the inverter battery breaker as
well. I know this "micro battery for GTB" is becoming a trend, but it
doesn't mean its right.  
Ray Walters
Remote Solar
303 505-8760
 On 5/23/20
5:48 PM, Mick Abraham wrote:  Greetings, All~ Mark Frye had asked: "...with
a 4000w Outback Radian, AC coupled with 2000w of PV, what is the smallest
Li battery I would want for stable operation?"   Mick's reply: In the
lithium arena, one often finds the ratings in kilowatt-hours rather than in
amp-hours. This is an easy conversion for us energy nerds to make, so below
I'm mainly using watts & watt-hours with occasional conversions to
amp-hours.   I suggest that you start with the spec sheet (of whichever
brand lithium battery is on your radar), & see what the manufacturer says
about "allowable rate of recharge". You may find that C/2 is an acceptable
rate with several manufacturers, Mark--much faster than what we're
accustomed to with typical lead-acid batteries. Let's assume:   * ...that
your AC coupled PV array crests around 1800 watts to the battery when there
are no loads * ...that the battery is below 100% state of charge, and *
...that the solar conditions are optimal.Let's further assume that
those conditions represent your battery's highest energy rate in either
direction.1800w X two hours = 3,600 watt-hours dividing by 48v nominal
= 75 amp-hours in the above hypothetical situation.   
++   The rate at which a battery can receive
energy is (usually) also the rate at which it can comfortably deplete, so
let's briefly look at the flip side: Assuming the battery mfr. wants the
watt-hours to be no less than two times the maximum wattage, a 3600
watt-hour (C/2) battery should not be depleted faster than 1800 watts. Your
4kW Radian, Mark, could exceed that if the loads demand it--& maybe your
loads don't. Motor starting surges should probably be part of the thinking
& it wouldn't hurt to ask the mfr.'s opinion about short term surges which
briefly deplete the battery faster than the hypothetical two hour rate.  
By approaching this question based on the battery manufacturer do's ">ᐧ


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Re: [RE-wrenches] How much Li battery?

[Jay]

One question I have for those more versed than me in lithium is, I’m under the 
impression that having a lithium battery in float for years isn’t good for it. 
Or at the very least it has to be cycled with some regularity. 

I’d like to hear data on that

Thx
Jay

Peltz power. 





> On May 23, 2020, at 10:08 PM, Ray  wrote:
> 
> 
> I suggest starting with a very simple look at the continuous output rating of 
> the battery and match that to the inverter continuous rating. This ends up 
> with quite a bit more battery than you might think at first.  However, if the 
> customer paid the big bucks for a battery backup system, they should at least 
> get enough battery to operate the inverter at its rated power.  Anything 
> less, I would consider poor design.  The same goes for lead acid batteries, 
> they just don't work well, even on grid, when the battery is undersized.  
> Even lead acid batteries have maximum current output ratings that should at 
> least be matched to the inverter rating.   
> 
> If you WERE going to under size the battery, then you should keep it safe by 
> reducing the size of the inverter battery breaker as well.   I know this 
> "micro battery for GTB" is becoming a trend, but it doesn't mean its right. 
> 
> Ray Walters
> Remote Solar
> 303 505-8760
>> On 5/23/20 5:48 PM, Mick Abraham wrote:
>> Greetings, All~ Mark Frye had asked:  "...with a 4000w Outback Radian, AC 
>> coupled with 2000w of PV, what is the smallest Li battery I would want for 
>> stable operation?"  
>> 
>> Mick's reply: In the lithium arena, one often finds the ratings in 
>> kilowatt-hours rather than in amp-hours. This is an easy conversion for us 
>> energy nerds to make, so below I'm mainly using watts & watt-hours with 
>> occasional conversions to amp-hours.
>> 
>> I suggest that you start with the spec sheet (of whichever brand lithium 
>> battery is on your radar), & see what the manufacturer says about "allowable 
>> rate of recharge". You may find that C/2 is an acceptable rate with several 
>> manufacturers, Mark--much faster than what we're accustomed to with typical 
>> lead-acid batteries. Let's assume:
>> 
>> * ...that your AC coupled PV array crests around 1800 watts to the battery 
>> when there are no loads
>> * ...that the battery is below 100% state of charge, and
>> * ...that the solar conditions are optimal. 
>> 
>> Let's further assume that those conditions represent your battery's highest 
>> energy rate in either direction. 
>> 
>> 1800w X two hours = 3,600 watt-hours dividing by 48v nominal = 75 amp-hours 
>> in the above hypothetical situation. 
>> 
>> ++
>> 
>> The rate at which a battery can receive energy is (usually) also the rate at 
>> which it can comfortably deplete, so let's briefly look at the flip side: 
>> Assuming the battery mfr. wants the watt-hours to be no less than two times 
>> the maximum wattage, a 3600 watt-hour (C/2) battery should not be depleted 
>> faster than 1800 watts. Your 4kW Radian, Mark, could exceed that if the 
>> loads demand it--& maybe your loads don't. Motor starting surges should 
>> probably be part of the thinking & it wouldn't hurt to ask the mfr.'s 
>> opinion about short term surges which briefly deplete the battery faster 
>> than the hypothetical two hour rate.
>> 
>> By approaching this question based on the battery manufacturer do's & 
>> don'ts, one improves the chance of getting warranty coverage should it later 
>> be needed. "What the large print giveth, the fine print taketh away." 
>> 
>> The Wrench List is the Bomb!  
>> 
>> Mick Abraham, Proprietor
>> www.abrahamsolar.com
>> 
>> Landline: 970-731-4675
>> Cell phone or for text messaging: 970-946-6584
>> ᐧ
>> 
>> 
>> ___
>> List sponsored by Redwood Alliance
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Re: [RE-wrenches] How much Li battery?

[Ray]

I suggest starting with a very simple look at the continuous output 
rating of the battery and match that to the inverter continuous rating. 
This ends up with quite a bit more battery than you might think at 
first.  However, if the customer paid the big bucks for a battery backup 
system, they should at least get enough battery to operate the inverter 
at its rated power.  Anything less, I would consider poor design.  The 
same goes for lead acid batteries, they just don't work well, even on 
grid, when the battery is undersized.  Even lead acid batteries have 
maximum current output ratings that should at least be matched to the 
inverter rating.


If you WERE going to under size the battery, then you should keep it 
safe by reducing the size of the inverter battery breaker as well.   I 
know this "micro battery for GTB" is becoming a trend, but it doesn't 
mean its right.


Ray Walters
Remote Solar
303 505-8760

On 5/23/20 5:48 PM, Mick Abraham wrote:
Greetings, All~ Mark Frye had asked:  "...with a 4000w Outback Radian, 
AC coupled with 2000w of PV, what is the smallest Li battery I would 
want for stable operation?"


Mick's reply: In the lithium arena, one often finds the ratings in 
kilowatt-hours rather than in amp-hours. This is an easy conversion 
for us energy nerds to make, so below I'm mainly using watts & 
watt-hours with occasional conversions to amp-hours.


I suggest that you start with the spec sheet (of whichever brand 
lithium battery is on your radar), & see what the manufacturer says 
about "allowable rate of recharge". You may find that C/2 is an 
acceptable rate with several manufacturers, Mark--much faster than 
what we're accustomed to with typical lead-acid batteries. Let's assume:


* ...that your AC coupled PV array crests around 1800 watts to the 
battery when there are no loads

* ...that the battery is below 100% state of charge, and
* ...that the solar conditions are optimal.

Let's further assume that those conditions represent your battery's 
highest energy rate in either direction.


1800w X two hours = 3,600 watt-hours dividing by 48v nominal = 75 
amp-hours in the above hypothetical situation.


++

The rate at which a battery can receive energy is (usually) also the 
rate at which it can comfortably deplete, so let's briefly look at the 
flip side: Assuming the battery mfr. wants the watt-hours to be no 
less than two times the maximum wattage, a 3600 watt-hour (C/2) 
battery should not be depleted faster than 1800 watts. Your 4kW 
Radian, Mark, could exceed that if the loads demand it--& maybe your 
loads don't. Motor starting surges should probably be part of the 
thinking & it wouldn't hurt to ask the mfr.'s opinion about short term 
surges which briefly deplete the battery faster than the hypothetical 
two hour rate.


By approaching this question based on the battery manufacturer do's & 
don'ts, one improves the chance of getting warranty coverage should it 
later be needed. "What the large print giveth, the fine print taketh 
away."


The Wrench List is the Bomb!

Mick Abraham, Proprietor
www.abrahamsolar.com 

Landline: 970-731-4675
Cell phone or for text messaging: 970-946-6584
ᐧ

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Re: [RE-wrenches] How much Li battery?

[Mick Abraham]

Greetings, All~ Mark Frye had asked:  "...with a 4000w Outback Radian, AC
coupled with 2000w of PV, what is the smallest Li battery I would want for
stable operation?"

Mick's reply: In the lithium arena, one often finds the ratings in
kilowatt-hours rather than in amp-hours. This is an easy conversion for us
energy nerds to make, so below I'm mainly using watts & watt-hours with
occasional conversions to amp-hours.

I suggest that you start with the spec sheet (of whichever brand lithium
battery is on your radar), & see what the manufacturer says about
"allowable rate of recharge". You may find that C/2 is an acceptable rate
with several manufacturers, Mark--much faster than what we're accustomed to
with typical lead-acid batteries. Let's assume:

* ...that your AC coupled PV array crests around 1800 watts to the battery
when there are no loads
* ...that the battery is below 100% state of charge, and
* ...that the solar conditions are optimal.

Let's further assume that those conditions represent your battery's highest
energy rate in either direction.

1800w X two hours = 3,600 watt-hours dividing by 48v nominal = 75 amp-hours
in the above hypothetical situation.

++

The rate at which a battery can receive energy is (usually) also the rate
at which it can comfortably deplete, so let's briefly look at the flip
side: Assuming the battery mfr. wants the watt-hours to be no less than two
times the maximum wattage, a 3600 watt-hour (C/2) battery should not be
depleted faster than 1800 watts. Your 4kW Radian, Mark, could exceed that
if the loads demand it--& maybe your loads don't. Motor starting surges
should probably be part of the thinking & it wouldn't hurt to ask the
mfr.'s opinion about short term surges which briefly deplete the battery
faster than the hypothetical two hour rate.

By approaching this question based on the battery manufacturer do's &
don'ts, one improves the chance of getting warranty coverage should it
later be needed. "What the large print giveth, the fine print taketh away."

The Wrench List is the Bomb!

Mick Abraham, Proprietor
www.abrahamsolar.com

Landline: 970-731-4675
Cell phone or for text messaging: 970-946-6584
ᐧ
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Re: [RE-wrenches] How much Li battery?

[Jerry Shafer]

Just me but that small l would be surprised  but again I like bigger gas
tanks over small ones

On Sat, May 23, 2020, 12:02 PM Mark Frye  wrote:

> Humm, so maybe a 3kwhr would work for my situation.
> On 5/23/2020 10:55 AM, Jerry Shafer wrote:
>
> Mark
> The smallest battery I have used is the Blue Planet 8 kWhr. its a half
> stack in there cabinet with a 10.8 k PS-3 inverter system with about 6 k on
> the roof, 8 K is not much but this particular customer only uses this for
> some low demand power consumption that must operate. It is less expensive
> to go with 16 kWhrs vs 8 at a cost per watt also
> Jerry
>
> On Sat, May 23, 2020 at 10:37 AM Mark Frye 
> wrote:
>
>> In the way back machine I remember being at a product roll out meeting
>> for the brand new Outback FX inverter. I asked the engineer, what was
>> the smallest battery bank that could be connected to the inverter. He
>> said on the fly that probably you would want the battery to "weight" at
>> least as much as the inverter. I thought that was a great answer.
>>
>> Fast forward, with a 4000w Outback Radian, AC coupled with 2000w of PV,
>> what is the smallest Li battery I would want for stable operation?
>>
>> My loads don't really need more than 40ah of capacity.
>>
>> What is the latest best practice on this?
>>
>> Thanks.
>>
>>
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Re: [RE-wrenches] How much Li battery?

[Mark Frye]

Humm, so maybe a 3kwhr would work for my situation.

On 5/23/2020 10:55 AM, Jerry Shafer wrote:

Mark
The smallest battery I have used is the Blue Planet 8 kWhr. its a half 
stack in there cabinet with a 10.8 k PS-3 inverter system with about 6 
k on the roof, 8 K is not much but this particular customer only uses 
this for some low demand power consumption that must operate. It is 
less expensive to go with 16 kWhrs vs 8 at a cost per watt also

Jerry

On Sat, May 23, 2020 at 10:37 AM Mark Frye > wrote:


In the way back machine I remember being at a product roll out
meeting
for the brand new Outback FX inverter. I asked the engineer, what was
the smallest battery bank that could be connected to the inverter. He
said on the fly that probably you would want the battery to
"weight" at
least as much as the inverter. I thought that was a great answer.

Fast forward, with a 4000w Outback Radian, AC coupled with 2000w
of PV,
what is the smallest Li battery I would want for stable operation?

My loads don't really need more than 40ah of capacity.

What is the latest best practice on this?

Thanks.


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Re: [RE-wrenches] How much Li battery?

[Jerry Shafer]

Mark
The smallest battery I have used is the Blue Planet 8 kWhr. its a half
stack in there cabinet with a 10.8 k PS-3 inverter system with about 6 k on
the roof, 8 K is not much but this particular customer only uses this for
some low demand power consumption that must operate. It is less expensive
to go with 16 kWhrs vs 8 at a cost per watt also
Jerry

On Sat, May 23, 2020 at 10:37 AM Mark Frye  wrote:

> In the way back machine I remember being at a product roll out meeting
> for the brand new Outback FX inverter. I asked the engineer, what was
> the smallest battery bank that could be connected to the inverter. He
> said on the fly that probably you would want the battery to "weight" at
> least as much as the inverter. I thought that was a great answer.
>
> Fast forward, with a 4000w Outback Radian, AC coupled with 2000w of PV,
> what is the smallest Li battery I would want for stable operation?
>
> My loads don't really need more than 40ah of capacity.
>
> What is the latest best practice on this?
>
> Thanks.
>
>
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[RE-wrenches] How much Li battery?

[Mark Frye]

In the way back machine I remember being at a product roll out meeting 
for the brand new Outback FX inverter. I asked the engineer, what was 
the smallest battery bank that could be connected to the inverter. He 
said on the fly that probably you would want the battery to "weight" at 
least as much as the inverter. I thought that was a great answer.


Fast forward, with a 4000w Outback Radian, AC coupled with 2000w of PV, 
what is the smallest Li battery I would want for stable operation?


My loads don't really need more than 40ah of capacity.

What is the latest best practice on this?

Thanks.


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