[EVDL] BMS question

[EV List Lackey via EV]

The following inquiry is reposted from the Solectria EV discussion list.  
I'll forward any responses back to that list.  Thanks!

> Looks like my CALB cells are getting close to the end of their lives. The
> capacities have been changing quite a bit over the past several months.
> The car itself is still doing great so I´m considering the purchase of a
> new battery pack. I´ve run my car for the past 9-10 years without using a
> BMS and until these recent cell variations it has been pretty much
> uneventful. If I decide to replace the pack I think I might install a BMS
> just to be able to keep a closer eye on things. So I´m looking for
> suggestions. What I´d like from a BMS is cell monitoring, reliability and
> simplicity. Something easy to  install and use. Thanks in advance.  

David Roden, EVDL moderator & general lackey

To reach me, don't reply to this message; I won't get it.  Use my 
offlist address here : http://evdl.org/help/index.html#supt

= = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = 
 I wish there was a knob on the TV to turn up the intelligence.  
 There's a knob called "brightness," but it doesn't work. 

  -- Gallagher
= = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = 

___
Address messages to ev@lists.evdl.org
No other addresses in TO and CC fields
UNSUBSCRIBE: http://www.evdl.org/sub/index.html
CONFIG: http://lists.evdl.org/options.cgi/ev-evdl.org
ARCHIVE: http://www.evdl.org/archive/
INFO: http://lists.evdl.org/listinfo.cgi/ev-evdl.org

Re: [EVDL] BMS question

[Peter VanDerWal via EV]

I was just looking into this recently.  There appear to be two types of cheap 
BMS systems, ones that just equalize when the batteries near full charge (put a 
small load, 40-70mv, on cells when they get over 4.1V) and the other type is 
typically called an "Active Balancer" it runs continuously and shuffles around 
charges when the cells differ by more than 10mv, many of these can move up to 
1-2Amps

I think the active ones sound like a better solution, although if you have a 
well matched series of cells a top balancer might be adequate.

Here is an example of an active balancer: 
https://www.aliexpress.com/item/1005002950596126.html
I have no idea how reliable these are, but at that price it's cheap enough to 
buy and test.
I also like that this particular model has a switch where you can disable the 
balancer action if the cell voltage drops below 3V, that way your balancer 
won't drain a dead battery.
Note: the above model does NOT handle over charge or over discharge.

That may not be an issue if your battery charger can limit it's max voltage and 
if your motor controller can automatically shut off when battery voltage drops 
below a set level.

My PGP public key: https://vanderwal.us/evdl_pgp.key

October 6, 2021 4:25 PM, "steve sawtelle via EV"  wrote:

> I guess this may qualify as an old-school question now.
> 
> About 12 years ago I built an electric motorcycle. I actually had it up and 
> running, but other
> things got in the way and I am abandoning the project. The rolling chassis 
> will get back it's ICE
> and I need to find a home for the 7" Jim Husted motor and the controls. I 
> have a new endeavor now -
> a small cruising sailboat (CLC Pocketship). I'm thinking of using a trolling 
> motor as the backup to
> the sails and I hope to repurpose some of my 100 A-H Thundersky batteries for 
> power. My batteries
> have been sitting for 10 years but still are at around 3.25V. I need to cycle 
> them to see if they
> are still viable of course. If they are, what BMS is recommended for them 
> now? I did a bit of
> searching but didn't see much.
> 
> -steve
> ___
> Address messages to ev@lists.evdl.org
> No other addresses in TO and CC fields
> UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
> ARCHIVE: http://www.evdl.org/archive
> LIST INFO: http://lists.evdl.org/listinfo.cgi/ev-evdl.org
___
Address messages to ev@lists.evdl.org
No other addresses in TO and CC fields
UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
ARCHIVE: http://www.evdl.org/archive/
LIST INFO: http://lists.evdl.org/listinfo.cgi/ev-evdl.org

Re: [EVDL] BMS question

[Lawrence Winiarski via EV]

For just a few batteries, I'd look at what the Radio Control guys use.    I 
think they have built in BMS and some are programmable.Being as you are only 
going to have 4 (for 12 volt trolling), I think you could get a complete 
solution cheap.    I think they use differentterminology like "4S" for 4 in 
series.  

Larry

p.s.   From experience.   Get a 50amp or above trolling motor.    Small ones 
are "okay" in light winds, but if you've got to 
buck a 20mph wind, you'd be much happier with a larger one when it's blowing.   

yes it's ev blasphemy but I'd also look at a metal pair of oarlocks and 
moderately decent 2-part oars. Always good to have several power sourcesif 
you get stuck in a shipping channel with no wind.  You don't have to do 
anything fancy with a sliding seat.  You can row standing up or sitting on a 
cooler or anything temporary.   It's a "LOT" better than a canoe paddle.    
You may find it's even better than thetrolling motor as you can save the 
electricity for lights and radio and gps. Expect only about 2 knots rowing.

 

On Thursday, October 7, 2021, 2:57:46 PM PDT, steve sawtelle via EV 
 wrote:  
 
  Thanks all for the advise and ideas.

I joined the Electricboats list - excellent resource! There is also a PlugBoats 
website/journal which looks good.

I borrowed our electronic load from work and will cycle a few batteries to see 
what I have. Good to know it may take a few cycles to see where they are at. 

I also found an excellent resource on Lithium batteries on boats:

https://nordkyndesign.com/category/marine-engineering/electrical/lithium-battery-systems/

Very thoughtful look at what it takes to make a good BMS. It's not easy. I'm 
hoping to do slow charge from a small solar panel and use the batteries weekly. 
It looks like it may be a bit hard to make that work really well. Well, part of 
why I do things like this is to learn

-steve

    On Thursday, October 7, 2021, 11:15:12 AM EDT, paul dove via EV 
 wrote:  
 
  I don't know anything about BMS's but Lithium Iron Phosphate cells can 
experience capacity fade even if they have good voltage. I had some cells that 
sat around for a year and a half and showed good voltage but when I cycles them 
they only had 45Ah out of 100Ah they started with. I thought I ruined them but 
I got back 100% of the capacity after the 5th cycle so just note you may need 
to cycle more than once.

    On Thursday, October 7, 2021, 8:11:11 AM CDT, Rod Hower via EV 
 wrote:  
 
  There are great resources for electric powered sail boats at 
electricbo...@groups.io https://groups.io/g/electricboats 
    On Wednesday, October 6, 2021, 07:25:44 PM EDT, steve sawtelle via EV 
 wrote:  
 
 I guess this may qualify as an old-school question now.

About 12 years ago I built an electric motorcycle. I actually had it up and 
running, but other things got in the way and I am abandoning the project.  The 
rolling chassis will get back it's ICE and I need to find a home for the 7" Jim 
Husted motor and the controls. I have a new endeavor now - a small cruising 
sailboat (CLC Pocketship). I'm thinking of using a trolling motor as the backup 
to the sails and I hope to repurpose some of my 100 A-H Thundersky batteries 
for power. My batteries have been sitting for 10 years but still are at around 
3.25V. I need to cycle them to see if they are still viable of course. If they 
are, what BMS is recommended for them now? I did a  bit of searching but didn't 
see much.

-steve
___
Address messages to ev@lists.evdl.org
No other addresses in TO and CC fields
UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
ARCHIVE: http://www.evdl.org/archive/
LIST INFO: http://lists.evdl.org/listinfo.cgi/ev-evdl.org
  
-- next part --
An HTML attachment was scrubbed...
URL: 

___
Address messages to ev@lists.evdl.org
No other addresses in TO and CC fields
UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
ARCHIVE: http://www.evdl.org/archive/
LIST INFO: http://lists.evdl.org/listinfo.cgi/ev-evdl.org
  
-- next part --
An HTML attachment was scrubbed...
URL: 

___
Address messages to ev@lists.evdl.org
No other addresses in TO and CC fields
UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
ARCHIVE: http://www.evdl.org/archive/
LIST INFO: http://lists.evdl.org/listinfo.cgi/ev-evdl.org
  
-- next part --
An HTML attachment was scrubbed...
URL: 

___
Address messages to ev@lists.evdl.org
No other addresses in TO and CC fields

Re: [EVDL] BMS question

[steve sawtelle via EV]

 Thanks all for the advise and ideas.

I joined the Electricboats list - excellent resource! There is also a PlugBoats 
website/journal which looks good.

I borrowed our electronic load from work and will cycle a few batteries to see 
what I have. Good to know it may take a few cycles to see where they are at. 

I also found an excellent resource on Lithium batteries on boats:

https://nordkyndesign.com/category/marine-engineering/electrical/lithium-battery-systems/

Very thoughtful look at what it takes to make a good BMS. It's not easy. I'm 
hoping to do slow charge from a small solar panel and use the batteries weekly. 
It looks like it may be a bit hard to make that work really well. Well, part of 
why I do things like this is to learn

-steve

 On Thursday, October 7, 2021, 11:15:12 AM EDT, paul dove via EV 
 wrote:  
 
  I don't know anything about BMS's but Lithium Iron Phosphate cells can 
experience capacity fade even if they have good voltage. I had some cells that 
sat around for a year and a half and showed good voltage but when I cycles them 
they only had 45Ah out of 100Ah they started with. I thought I ruined them but 
I got back 100% of the capacity after the 5th cycle so just note you may need 
to cycle more than once.

    On Thursday, October 7, 2021, 8:11:11 AM CDT, Rod Hower via EV 
 wrote:  
 
  There are great resources for electric powered sail boats at 
electricbo...@groups.io https://groups.io/g/electricboats 
    On Wednesday, October 6, 2021, 07:25:44 PM EDT, steve sawtelle via EV 
 wrote:  
 
 I guess this may qualify as an old-school question now.

About 12 years ago I built an electric motorcycle. I actually had it up and 
running, but other things got in the way and I am abandoning the project.  The 
rolling chassis will get back it's ICE and I need to find a home for the 7" Jim 
Husted motor and the controls. I have a new endeavor now - a small cruising 
sailboat (CLC Pocketship). I'm thinking of using a trolling motor as the backup 
to the sails and I hope to repurpose some of my 100 A-H Thundersky batteries 
for power. My batteries have been sitting for 10 years but still are at around 
3.25V. I need to cycle them to see if they are still viable of course. If they 
are, what BMS is recommended for them now? I did a  bit of searching but didn't 
see much.

-steve
___
Address messages to ev@lists.evdl.org
No other addresses in TO and CC fields
UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
ARCHIVE: http://www.evdl.org/archive/
LIST INFO: http://lists.evdl.org/listinfo.cgi/ev-evdl.org
  
-- next part --
An HTML attachment was scrubbed...
URL: 

___
Address messages to ev@lists.evdl.org
No other addresses in TO and CC fields
UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
ARCHIVE: http://www.evdl.org/archive/
LIST INFO: http://lists.evdl.org/listinfo.cgi/ev-evdl.org
  
-- next part --
An HTML attachment was scrubbed...
URL: 

___
Address messages to ev@lists.evdl.org
No other addresses in TO and CC fields
UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
ARCHIVE: http://www.evdl.org/archive/
LIST INFO: http://lists.evdl.org/listinfo.cgi/ev-evdl.org
  
-- next part --
An HTML attachment was scrubbed...
URL: 

___
Address messages to ev@lists.evdl.org
No other addresses in TO and CC fields
UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
ARCHIVE: http://www.evdl.org/archive/
LIST INFO: http://lists.evdl.org/listinfo.cgi/ev-evdl.org

Re: [EVDL] BMS question

[paul dove via EV]

 I don't know anything about BMS's but Lithium Iron Phosphate cells can 
experience capacity fade even if they have good voltage. I had some cells that 
sat around for a year and a half and showed good voltage but when I cycles them 
they only had 45Ah out of 100Ah they started with. I thought I ruined them but 
I got back 100% of the capacity after the 5th cycle so just note you may need 
to cycle more than once.

On Thursday, October 7, 2021, 8:11:11 AM CDT, Rod Hower via EV 
 wrote:  
 
  There are great resources for electric powered sail boats at 
electricbo...@groups.io https://groups.io/g/electricboats 
    On Wednesday, October 6, 2021, 07:25:44 PM EDT, steve sawtelle via EV 
 wrote:  
 
 I guess this may qualify as an old-school question now.

About 12 years ago I built an electric motorcycle. I actually had it up and 
running, but other things got in the way and I am abandoning the project.  The 
rolling chassis will get back it's ICE and I need to find a home for the 7" Jim 
Husted motor and the controls. I have a new endeavor now - a small cruising 
sailboat (CLC Pocketship). I'm thinking of using a trolling motor as the backup 
to the sails and I hope to repurpose some of my 100 A-H Thundersky batteries 
for power. My batteries have been sitting for 10 years but still are at around 
3.25V. I need to cycle them to see if they are still viable of course. If they 
are, what BMS is recommended for them now? I did a  bit of searching but didn't 
see much.

-steve
___
Address messages to ev@lists.evdl.org
No other addresses in TO and CC fields
UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
ARCHIVE: http://www.evdl.org/archive/
LIST INFO: http://lists.evdl.org/listinfo.cgi/ev-evdl.org
  
-- next part --
An HTML attachment was scrubbed...
URL: 

___
Address messages to ev@lists.evdl.org
No other addresses in TO and CC fields
UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
ARCHIVE: http://www.evdl.org/archive/
LIST INFO: http://lists.evdl.org/listinfo.cgi/ev-evdl.org
  
-- next part --
An HTML attachment was scrubbed...
URL: 

___
Address messages to ev@lists.evdl.org
No other addresses in TO and CC fields
UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
ARCHIVE: http://www.evdl.org/archive/
LIST INFO: http://lists.evdl.org/listinfo.cgi/ev-evdl.org

Re: [EVDL] BMS question

[Rod Hower via EV]

 There are great resources for electric powered sail boats at 
electricbo...@groups.io https://groups.io/g/electricboats 
On Wednesday, October 6, 2021, 07:25:44 PM EDT, steve sawtelle via EV 
 wrote:  
 
 I guess this may qualify as an old-school question now.

About 12 years ago I built an electric motorcycle. I actually had it up and 
running, but other things got in the way and I am abandoning the project.  The 
rolling chassis will get back it's ICE and I need to find a home for the 7" Jim 
Husted motor and the controls. I have a new endeavor now - a small cruising 
sailboat (CLC Pocketship). I'm thinking of using a trolling motor as the backup 
to the sails and I hope to repurpose some of my 100 A-H Thundersky batteries 
for power. My batteries have been sitting for 10 years but still are at around 
3.25V. I need to cycle them to see if they are still viable of course. If they 
are, what BMS is recommended for them now? I did a  bit of searching but didn't 
see much.

-steve
___
Address messages to ev@lists.evdl.org
No other addresses in TO and CC fields
UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
ARCHIVE: http://www.evdl.org/archive/
LIST INFO: http://lists.evdl.org/listinfo.cgi/ev-evdl.org
  
-- next part --
An HTML attachment was scrubbed...
URL: 

___
Address messages to ev@lists.evdl.org
No other addresses in TO and CC fields
UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
ARCHIVE: http://www.evdl.org/archive/
LIST INFO: http://lists.evdl.org/listinfo.cgi/ev-evdl.org

[EVDL] BMS question

[steve sawtelle via EV]

I guess this may qualify as an old-school question now.

About 12 years ago I built an electric motorcycle. I actually had it up and 
running, but other things got in the way and I am abandoning the project.  The 
rolling chassis will get back it's ICE and I need to find a home for the 7" Jim 
Husted motor and the controls. I have a new endeavor now - a small cruising 
sailboat (CLC Pocketship). I'm thinking of using a trolling motor as the backup 
to the sails and I hope to repurpose some of my 100 A-H Thundersky batteries 
for power. My batteries have been sitting for 10 years but still are at around 
3.25V. I need to cycle them to see if they are still viable of course. If they 
are, what BMS is recommended for them now? I did a  bit of searching but didn't 
see much.

-steve
___
Address messages to ev@lists.evdl.org
No other addresses in TO and CC fields
UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
ARCHIVE: http://www.evdl.org/archive/
LIST INFO: http://lists.evdl.org/listinfo.cgi/ev-evdl.org