EV Digest 7013
Topics covered in this issue include:
1) Re: Ideal EV configuration for my situation?
by Victor Tikhonov <[EMAIL PROTECTED]>
2) Re: Ideal EV configuration for my situation?
by "Andrew Kane" <[EMAIL PROTECTED]>
3) Re: Balancing NiCad batteries?
by "David Roden" <[EMAIL PROTECTED]>
4) LED headlights
by Danny Miller <[EMAIL PROTECTED]>
5) Re: Ideal EV configuration for my situation?
by "Matthew Chan" <[EMAIL PROTECTED]>
6) Re: Efficiency of lead acid batteries
by "Peter VanDerWal" <[EMAIL PROTECTED]>
7) Re: Ideal EV configuration for my situation?
by "Peter VanDerWal" <[EMAIL PROTECTED]>
8) Re: Efficiency of lead acid batteries
by "Shaun Williams" <[EMAIL PROTECTED]>
9) todd pc25lv dc-dc converter specs
by Michael Mohlere <[EMAIL PROTECTED]>
10) Re: todd pc25lv dc-dc converter specs
by "patrick DonEgan" <[EMAIL PROTECTED]>
11) Go get the records at Wayland Invite!!!
by [EMAIL PROTECTED]
12) RE: conversion question
by "Tom S." <[EMAIL PROTECTED]>
13) Re: Efficiency of lead acid batteries
by Rob&Amy Smith <[EMAIL PROTECTED]>
14) Re: Efficiency of lead acid batteries
by "Phil Marino" <[EMAIL PROTECTED]>
15) Re: Efficiency of lead acid batteries
by "compton" <[EMAIL PROTECTED]>
16) Re: conversion question - rolling resistance
by Jeff Shanab <[EMAIL PROTECTED]>
17) Re: Efficiency of lead acid batteries
by "Phil Marino" <[EMAIL PROTECTED]>
18) Re: Efficiency of lead acid batteries
by "Phil Marino" <[EMAIL PROTECTED]>
19) RE: Efficiency of lead acid batteries
by "Phil Marino" <[EMAIL PROTECTED]>
20) RE: conversion question
by "Phil Marino" <[EMAIL PROTECTED]>
21) Energy unit conversion and comparison
by "Richard Acuti" <[EMAIL PROTECTED]>
22) Re: Energy unit conversion and comparison
by "Zeke Yewdall" <[EMAIL PROTECTED]>
23) Re: Efficiency of lead acid batteries
by "Peter VanDerWal" <[EMAIL PROTECTED]>
--- Begin Message ---
Matthew Chan wrote:
Thanks for all the quick and insightful replies guys. I think it helped
a lot.
I ended up calling Victor today and, after getting over that initial
sticker shock, realized that it probably wasn't possible to go AC.
Peter's email confirmed that for me.
That's funny (about sticker shock). If you'd call me after calling
ACP or UQM for a quote, you'd feel rather relief. That's called
theory of relativity :-)
--
Victor
'91 ACRX - something different
--- End Message ---
--- Begin Message ---
Hi Matt,
It seems to me that unless you use a kit (unavailable AFAIK for
the Mercedes) you will have to machine at least an adapter plate,
unless you use direct drive- which you have said you don't plan to do.
That being said, an adapter plate is basically two-dimensional and
doesn't require nearly the 0.00001" precision of which those CNC
machines are no doubt capable.
If your machine shop doesn't have any old-fashioned manual table
mills I'm surprised. I would be even more surprised if such a machine
is entirely unavailable in Toronto (or any city of similar size). I
don't see any reason why you couldn't farm the job of fabricating the
adapter plate out to a machine shop and include that cost in the
conversion budget as it's what most converters would need to do on a
vehicle for which no kit is available.
Good luck with your project!
On 7/11/07, Matthew Chan <[EMAIL PROTECTED]> wrote:
I just realized that I completely forgot to sign my last email. Oops.
I've come across a funny occurrence when playing with Uve's
calculator. It seems that I get the best mileage at first gear, 10mph
no matter what I set the gears at! Does this make sense? I know this
is the "lowest torque" situation, but the motor efficiency curves
don't seem to indicate that. When driving, should I just be waiting
till I hit the motor RPM limit before shifting to the next gear? Isn't
there a point when the motor just doesn't get the best mileage at
first gear?
Matt
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--- Begin Message ---
On 10 Jul 2007 at 13:33, Jerry McIntire wrote:
> SAFT NiCad batteries ...
You have some fine batteries there. If you ever want to sell them, I'll be
waiting with cash in hand, assuming they haven't been heavily abused or
cycled to death. Seriously.
(No, I don't particularly want the van they came in. ;-)
They are pretty sturdy and can withstand reasonable amounts of equalization
(read : they like to gas freely). You really don't need any kind of
balancers or regulators, IMO. The quick and easy way to charge them is to
buy a Brusa charger with the Saft profile. That's not a particularly cheap
way to charge them, however. ;-)
They love cold and lose very little capacity. The main thing to watch out
for is heat. Try not to charge or discharge at temperatures above 40 deg
C. Holding to 35 deg C is even better, if you can do it. Consistent
operation at 50 deg C will cut your cycle life in half. These are great
for Massachusetts, but probably not the best choice for Arizona or Southern
California.
You can grab the charging instructions and user manual for those batteries
in the EVDL library :
http://www.evdl.org/lib/
David Roden - Akron, Ohio, USA
EV List Administrator
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--- Begin Message ---
Oooh, got some stock of the latest LED emitters on the market, Luxeon
Rebels.
Not only are they more efficient, they're higher power and most
importantly significantly more tolerant of high temps. The 50K hr life
rating is with a 135C junction temperature. The thermal pad on back is
electrically neutral and solderable. A sizable copper PCB area (half a
sq in or so) can dissipate the heat and stay within specification, I
took measurements. And I wasn't pulling any special tricks here.
145 lumens at 2.52W is the book rating, although my part here has a
significantly lower forward voltage at the specified current and is only
drawing about 2W.
A low beam halogen is 1000 lumens or so. These devices are fairly
cheap, under $4 in singles.
The prob is these things spread light over 160 deg. That's a prob
because even a perfectly designed lens can only focus the light it
captures and even a foot-wide lens can't capture over 160 deg. Either
some will just be lost- without advanced computer-designed optics it
can't be redirected into a beam, it must be absorbed by an opaque
surface to prevent creating an unacceptable side beam. The reflector
design used in normal headlights would be problematic because the
heatsink is opaque and generally large which will block much of the
reflected beam unless we pull some tricks like a bigger reflector or a
smaller heatsink (water cooling would do nicely).
Well don't jump into it right away. Unless you're a genius this would
probably not work. And really the power savings aren't all that great.
Anyways, the devices went out of stock, I bought the last 3 high power
whites on the market right now (sorry fellows). They've got the lower
power bin ones available, like 10% less output for the same power input.
Danny
--- End Message ---
--- Begin Message ---
Hey guys,
I'm probably starting to approach flood-like email levels, but I think
real progress is being made, which is great.
I have a question regarding battery chargers and wiring patterns.
I need a 144VDC setup, so I was wondering how I should wire my
batteries. What does the term "string" mean? Are they just referring
to 2 series wired battery sets connected parallel?
Also, what kind of charger should I be looking into? Is it worth
getting a programmable charger? What kind of charging procedure would
I be looking at?
I was also looking at batteries today, and there was one company,
called power battery, which offered a battery that seemed identical to
the trojan T-105s. Should I bite? They're 20 dollars cheaper per unit,
2 pounds heavier, same rated capacity and size. At 25 batteries, that
means a $500 savings... They're also called Direct Power. Has anyone
had previous experience with these?
Lastly, where are the contactors usually placed in a system? Are they
between the battery pack and the controller? I'd be using 144VDC,
with who knows how many amps max. Which should I get? Are industrial
contactors an option?
Matt
--- End Message ---
--- Begin Message ---
Efficiency depends on how full you fill them and how much power you waste
equalizing them (equalization current is less than 0% efficient)
If you keep the SOC below the 80% or so (when they start gassing) they
/can/ be 90+% efficient.
However typical charging, to 100% SOC plus equalization, usually works out
to 75% or less, depending on how old the batteries are, how often and how
much you equalize, etc.
Also, just to confuse things, some people talk about charging efficiency
but only refer to columbic(sp?) efficiency, I.e. Amps in vs Amps out, and
totally ignore the voltage difference between charge and discharge.
> I've always heard lead-acid battery efficiency to be around 80-85% for
> flooded and ~90% on AGMs. I never hear at what current though.....
>
> On 7/10/07, Dan Frederiksen <[EMAIL PROTECTED]> wrote:
>> I seem to recall a spec sheet once saying that at only 100A the lead
>> acid battery was only 50% efficient. are lead acids really that
>> inefficient for EV use?
>> do they really waste that much at only 100A?
>>
>> and by implication does that mean a much more efficient battery type
>> like A123 can do just as good with half the capacity
>>
>>
>> Dan
>>
>>
>
>
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--- Begin Message ---
Check out the folks at grassroots EVs. They have a method for building
adapter plates using ordinary hand tools.
It's a little rough around the edges, but seems to get the job done. You
can buy a CD describing the process and other tips on building EVs.
http://www.grassrootsev.com/
> Thanks for the detailed replies guys.
>
> Mark, I was thinking about just changing the gears on the differential
> box and keeping the standard transmission stock. It should put me into
> that sweet spot for motor RPM. Also, I'm fully allowed to use the
> school's facilities, including the CNC machines and the ProE licenses.
> The students are also willing to help, and they'll be the ones
> physically doing the conversion. I'm just the designer and researcher.
>
> The problem is that I'm quite certain that most people won't have
> access to 4 axis CNC milling machines with $20 000 software licenses.
>
> I'm trying to make a project which is simple and reproducible under
> normal circumstances but at the same time, still giving acceptable
> performance and remaining economically viable. Ideally, this car
> should be able to be used anywhere in the city and pay itself off
> within 'x' number of years.
>
> Then I'm going to document everything and put it all online for people
> to copy/learn from. I've already started a work log.
>
> The reason that I'm trying to avoid the machine shop whenever possible
> is because I'm going to consider any machine shop use as "outsourced"
> and will add it to the bill of "cost". In reality, this won't cost us
> anything except for a few hours by students. However, if someone else
> were to reproduce this project, it would, most likely, cost them
> money, so for all intents and purposes, it "cost" us money too.
>
> Peter, it's good to hear that the zilla 1k is the ideal controller.
> What is the % efficiency on these units anyways?
>
> So other than these things... I think I may be set to determine a
> preliminary price, and a preliminary cost/benefit calculation! I'll
> get back to you guys with the numbers soon. I can't properly estimate
> the cost of the transmission or the shocks yet though.
>
>
--
If you send email to me, or the EVDL, that has > 4 lines of legalistic
junk at the end; then you are specifically authorizing me to do whatever I
wish with the message. By posting the message you agree that your long
legalistic signature is void.
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--- Begin Message ---
In effect, isn't the Peukert component a measure of efficiency of a
battery under load?
Therefore, as suggested, higher discharge rates reduce efficiency in
lead acid and this is not a characteristic of A123 cells?
On 7/10/07, Dan Frederiksen <[EMAIL PROTECTED]> wrote:
I seem to recall a spec sheet once saying that at only 100A the lead
acid battery was only 50% efficient. are lead acids really that
inefficient for EV use?
do they really waste that much at only 100A?
and by implication does that mean a much more efficient battery type
like A123 can do just as good with half the capacity
Shaun
www.electric-echo.com
--- End Message ---
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Why do I get this message SO much???
On 7/11/07, Michael Mohlere <[EMAIL PROTECTED]> wrote:
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--
Patrick Ira Donegan
TigerBody Electric Vehicles
--- End Message ---
--- Begin Message ---
John, Bill, and All,
First off congratulations John on your recent Awesome WZ runs and
records!!! I have been telling everyone around the world that the EV
drag racing world was soon to explode onto the main stage and you and
Bill are proving it. I have been out of the loop as of late but am
bringing myself up to speed on all that has happened in the NEDRA world
the past month. I have been trying to pull off a trip to Portland this
week with OJ and AGNS but it doesn't look like it will happen. I even
had a dragster driver in Bob Boyd and a truck and rig to haul
everything there and back but I just get out of a prior commitment for
Friday and Saturday. Bummer. OJ is ready to run and AGNS is almost
complete with a new 4 motor drive system. I wish all of you the best
of luck and safe runnings.
Shawn Lawless
________________________________________________________________________
AOL now offers free email to everyone. Find out more about what's free
from AOL at AOL.com.
--- End Message ---
--- Begin Message ---
Hi,
We could argue this all day, but the real issue is, you will never get as many
batteries in a conversion as the Evette,and a 4 wheel car can`t come close to
the maneuverability of the Evette. Agree or disagree.
Tom Sines
-----Original Message-----
>From: [EMAIL PROTECTED]
>Sent: Jul 11, 2007 1:11 AM
>To: ev@listproc.sjsu.edu
>Subject: RE: conversion question
>
>>> I disagree. I can push my car easily with one hand of a level
>>> street, I don`t think you can do that with a standard car.
>
>I just pushed my '81 300SD with one hand earlier today - certainly not a very
>*quantitative* measurement of what it takes to move an old luxury diesel. You
>probably haven't read the list before or you'd have remembered numerous posts
>on this - the most thorough converters minimize rolling resistance to the point
>of taking a "lady's gloved finger" to move a lead sled!
>
________________________________________
PeoplePC Online
A better way to Internet
http://www.peoplepc.com
--- End Message ---
--- Begin Message ---
I would assume this is yet another place that Peukert comes back to
kick your butt. For example, it looks like a 150Ah Trojan J150 will
only put out ~82Ah at 100A discharge. However, when you go to charge
it back up you're going to need to put 150Ah plus back into it.
Assuming the charge process is ~90% efficient (best case) you are
looking at 50% overall efficiency. Compare that to a 55Ah Optima D34
which still gives you 47Ah at 100A. With 90% charging efficiency
(maybe more realistic, equalize by regulators not overcharging) you
are looking at something more around 77% overall efficiency.
Rob
On Jul 11, 2007, at 3:11 AM, Peter VanDerWal wrote:
Efficiency depends on how full you fill them and how much power you
waste
equalizing them (equalization current is less than 0% efficient)
If you keep the SOC below the 80% or so (when they start gassing) they
/can/ be 90+% efficient.
However typical charging, to 100% SOC plus equalization, usually
works out
to 75% or less, depending on how old the batteries are, how often
and how
much you equalize, etc.
Also, just to confuse things, some people talk about charging
efficiency
but only refer to columbic(sp?) efficiency, I.e. Amps in vs Amps
out, and
totally ignore the voltage difference between charge and discharge.
I've always heard lead-acid battery efficiency to be around 80-85%
for
flooded and ~90% on AGMs. I never hear at what current though.....
On 7/10/07, Dan Frederiksen <[EMAIL PROTECTED]> wrote:
I seem to recall a spec sheet once saying that at only 100A the lead
acid battery was only 50% efficient. are lead acids really that
inefficient for EV use?
do they really waste that much at only 100A?
and by implication does that mean a much more efficient battery type
like A123 can do just as good with half the capacity
Dan
--
If you send email to me, or the EVDL, that has > 4 lines of legalistic
junk at the end; then you are specifically authorizing me to do
whatever I
wish with the message. By posting the message you agree that your
long
legalistic signature is void.
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--- Begin Message ---
From: Rob&Amy Smith <[EMAIL PROTECTED]>
Reply-To: ev@listproc.sjsu.edu
To: ev@listproc.sjsu.edu
Subject: Re: Efficiency of lead acid batteries
Date: Wed, 11 Jul 2007 01:55:32 -0700
I would assume this is yet another place that Peukert comes back to kick
your butt. For example, it looks like a 150Ah Trojan J150 will only put
out ~82Ah at 100A discharge. However, when you go to charge it back up
you're going to need to put 150Ah plus back into it.
No, you're not. The peukert effect prevents you from extracting the rated
charge, but you only have to put back the charge you took out ( plus a
percentage of loss). So, in your example, you have to put back 82 AH plus
some extra for charging inefficiency of the battery.
Phil Marino
Assuming the charge process is ~90% efficient (best case) you
are looking at 50% overall efficiency. Compare that to a 55Ah Optima D34
which still gives you 47Ah at 100A. With 90% charging efficiency (maybe
more realistic, equalize by regulators not overcharging) you are looking
at something more around 77% overall efficiency.
Rob
On Jul 11, 2007, at 3:11 AM, Peter VanDerWal wrote:
Efficiency depends on how full you fill them and how much power you waste
equalizing them (equalization current is less than 0% efficient)
If you keep the SOC below the 80% or so (when they start gassing) they
/can/ be 90+% efficient.
However typical charging, to 100% SOC plus equalization, usually works
out
to 75% or less, depending on how old the batteries are, how often and how
much you equalize, etc.
Also, just to confuse things, some people talk about charging efficiency
but only refer to columbic(sp?) efficiency, I.e. Amps in vs Amps out, and
totally ignore the voltage difference between charge and discharge.
I've always heard lead-acid battery efficiency to be around 80-85% for
flooded and ~90% on AGMs. I never hear at what current though.....
On 7/10/07, Dan Frederiksen <[EMAIL PROTECTED]> wrote:
I seem to recall a spec sheet once saying that at only 100A the lead
acid battery was only 50% efficient. are lead acids really that
inefficient for EV use?
do they really waste that much at only 100A?
and by implication does that mean a much more efficient battery type
like A123 can do just as good with half the capacity
Dan
--
If you send email to me, or the EVDL, that has > 4 lines of legalistic
junk at the end; then you are specifically authorizing me to do whatever
I
wish with the message. By posting the message you agree that your long
legalistic signature is void.
_________________________________________________________________
http://newlivehotmail.com
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--- Begin Message ---
On 9:55:32 am 07/11/07 Rob&Amy Smith <[EMAIL PROTECTED]> wrote:
> I would assume this is yet another place that Peukert comes back to
> kick your butt. For example, it looks like a 150Ah Trojan J150 will
> only put out ~82Ah at 100A discharge. However, when you go to charge
> it back up you're going to need to put 150Ah plus back into it.
No, no!
The energy hasn't disappeared due to Peukert, you just can't get to it.
Discharging a lead acid battery causes the formation of lead sulphate which
is an insulator. Discharging at higher currents tends to make the reaction
take place mostly at the surface of the plates, so you can litterally 'wall
up' active material behind an insulating layer of lead sulphate. If you
leave the battery to 'rest' the charge will diffuse from inside the plate
and 're-charge' the surface layer somewhat, which is the famous lead acid
'recovery'. If you increase the ratio of surface area to volume of the
plates then you can minumise the Peukert effect and this is exactly what a
Hawker or Optima is doing. The ultimate example was the Bolder TMF (Thin
Metal Film).
Coulombic efficiency (Ah in to Ah out) for some different battery types;
Lead acid (AGM) up to 90%
Lithium (Thundersky) 100%
NiCad 71%
NiMh 66%
The energy efficiency is then dependant on the difference between charge
and discharge voltage, so the NiMh can come out pretty badly. Hence the
need for a battery cooling system on the EV1.
The energy efficiency for a 100Ah Thundersky cell (cobalt chemistry) has
been measured at 84% (100A discharge and charge)
Paul Compton
www.evguru.co.uk
www.batteryvehiclesociety.org.uk
www.sciroccoev.co.uk
www.morini-mania.co.uk
www.compton.vispa.com/the_named
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--- Begin Message ---
Joseph said
"...There is something I do not understand though. Switching to a lower
rolling resistance tire is supposed to improve mpg by just a few
numbers...."
I wondered about this to but what if we look at it from the amount
wasted viewpoint.
I am gonna assume that the rolling resistance Times the weight is the
same,
but wait, my ev weights more! that means the effect will be higher already.
I only carry the usable equivalent of a gallon of gas on board.
An electric drivetrain is more efficient so if original was 35 miles I
may get 24miles range.
The loss from the rolling resistance is not related to the conversion
from chemical to mechanical energy.
Maybe these two things are how it becomes more of an issue in an EV.
ie
range = energy/(energy/mile)
(miles = gallons/mpg)
energy of ice = energy in gas * ice effiency(25%) - speed*wind
resistance - weight*speed*rolling resistance
(miles = kwh/wh/mile)
energy of ev = energy batteries * ElectricDriveTrain eff(80%) -
speed*wind resistance -weight*speed*rolling resistance
just a thought.
--- End Message ---
--- Begin Message ---
From: "Shaun Williams" <[EMAIL PROTECTED]>
Reply-To: ev@listproc.sjsu.edu
To: ev@listproc.sjsu.edu
Subject: Re: Efficiency of lead acid batteries
Date: Wed, 11 Jul 2007 20:22:19 +1000
In effect, isn't the Peukert component a measure of efficiency of a
battery under load?
No - it's a measure of usability of the charge.
Here's an analogy: discharging a lead acid battery at a high rate ( and
being unable to use all the energy because of the Peukert effect) is like
having the pickup in a gas tank a few inches above the bottom of the tank.
You can't draw out all of the fuel. But, you haven't lost efficiency for
the fuel you have used.
When you do refill the tank, you only have to put back the gas you used. (
and, in the case of the batteries) a bit extra for charge inefficiency.
It does seem like batteries with high Peukert effects also tend to have
higher internal resistance. High current draws with batteries that have
high internal resistance means energy is lost within the batteries (and show
up as heat), But, as far as I know, this energy loss is not directly due to
the Peukert effect.
Phil Marino
Therefore, as suggested, higher discharge rates reduce efficiency in
lead acid and this is not a characteristic of A123 cells?
On 7/10/07, Dan Frederiksen <[EMAIL PROTECTED]> wrote:
I seem to recall a spec sheet once saying that at only 100A the lead
acid battery was only 50% efficient. are lead acids really that
inefficient for EV use?
do they really waste that much at only 100A?
and by implication does that mean a much more efficient battery type
like A123 can do just as good with half the capacity
Shaun
www.electric-echo.com
_________________________________________________________________
http://liveearth.msn.com
--- End Message ---
--- Begin Message ---
From: "Peter VanDerWal" <[EMAIL PROTECTED]>
Reply-To: ev@listproc.sjsu.edu
To: ev@listproc.sjsu.edu
Subject: Re: Efficiency of lead acid batteries
Date: Wed, 11 Jul 2007 03:11:57 -0700 (MST)
Efficiency depends on how full you fill them and how much power you waste
equalizing them (equalization current is less than 0% efficient)
Do you really mean less than 0 %? I always thought that equalization might
not increase the level of charge for all of the cells involved, but, that
some cells would be brought to a higher state of charge ( so as to
"equalize" them to the more fullycharged cells.)
So, I see how equalization efficiency could be low, but what is your
thinking behind "less than 0%"?
If you keep the SOC below the 80% or so (when they start gassing) they
/can/ be 90+% efficient.
However typical charging, to 100% SOC plus equalization, usually works out
to 75% or less, depending on how old the batteries are, how often and how
much you equalize, etc.
Also, just to confuse things, some people talk about charging efficiency
but only refer to columbic(sp?) efficiency, I.e. Amps in vs Amps out, and
totally ignore the voltage difference between charge and discharge.
You mean amp-hours in vs amp-hours out, right??
Phil Marino
> I've always heard lead-acid battery efficiency to be around 80-85% for
> flooded and ~90% on AGMs. I never hear at what current though.....
>
> On 7/10/07, Dan Frederiksen <[EMAIL PROTECTED]> wrote:
>> I seem to recall a spec sheet once saying that at only 100A the lead
>> acid battery was only 50% efficient. are lead acids really that
>> inefficient for EV use?
>> do they really waste that much at only 100A?
>>
>> and by implication does that mean a much more efficient battery type
>> like A123 can do just as good with half the capacity
>>
>>
>> Dan
>>
>>
>
>
--
If you send email to me, or the EVDL, that has > 4 lines of legalistic
junk at the end; then you are specifically authorizing me to do whatever I
wish with the message. By posting the message you agree that your long
legalistic signature is void.
_________________________________________________________________
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--- Begin Message ---
From: Dan Frederiksen <[EMAIL PROTECTED]>
Reply-To: ev@listproc.sjsu.edu
To: ev@listproc.sjsu.edu
Subject: Efficiency of lead acid batteries
Date: Wed, 11 Jul 2007 04:44:45 +0200
I seem to recall a spec sheet once saying that at only 100A the lead acid
battery was only 50% efficient. are lead acids really that inefficient for
EV use?
No. Can you tell us where you read that?
do they really waste that much at only 100A?
No. Again, please share your source with us.
Phil Marino
and by implication does that mean a much more efficient battery type like
A123 can do just as good with half the capacity
Dan
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--- Begin Message ---
From: "Tom S." <[EMAIL PROTECTED]>
Reply-To: ev@listproc.sjsu.edu
To: ev@listproc.sjsu.edu
Subject: RE: conversion question
Date: Tue, 10 Jul 2007 22:05:41 -0400 (EDT)
Hi Rodger,
I`ve worked on about 30 conversions, theres no way you can push a 4 wheel
car as easy as mine, we disagree again.
By the way here some facts about our car
There is no left and right front end suspension, tires, ball joints,tie
rods,steering wheel,steering column,gas engine,no transmission,and no
beefed up frame in the front of the car to hold this stuff.Thats at least a
1000lbs of crap this car does not have.Now put batteries there instead. Too
bad your conversion has all that crap in it. There is no you can enough
batteries in a conversion.
Tom Sines
Tom -
Can you tell us what size, brand, and model tires you have ( front and back)
on your car?
If you don't know, you can read this information off the tire sidewalls.
Thanks
Phil Marino
-----Original Message-----
>From: Peter VanDerWal <[EMAIL PROTECTED]>
>Sent: Jul 10, 2007 8:48 PM
>To: ev@listproc.sjsu.edu
>Subject: RE: conversion question
>
>Many people on the list can push their car with one hand. I seem to
recall
>one (John Wayland?) or two mentioning they could do it with one finger.
>
>So I'd say that evidence is inconclusive.
>
>> Hi Rodger,
>>
>> I disagree. I can push my car easily with one hand of a level street, I
>> don`t think you can do that with a standard car. I`ve been testing
this
>> car for years,and could make many claims, however without an official
it
>> wood be meaningless, so i`ll just stick to the facts about the car.OK
>>
>> Tom Sines
>>
>> -----Original Message-----
>>>From: Roger Stockton <[EMAIL PROTECTED]>
>>>Sent: Jul 10, 2007 6:28 PM
>>>To: ev@listproc.sjsu.edu
>>>Subject: RE: conversion question
>>>
>>>Tom S. wrote:
>>>
>>>> Because this car is not a 4wheeler, but more like a two
>>>> wheeler I think the rolling resistance is up to 30% less.What
>>>> do you think?
>>>> Many of the parts a gas car we don`t.
>>>
>>>As a two wheeler you will 'save' the losses associated with the wheel
>>>bearing and brake drag on the missing front wheels. You will also save
>>>any rolling losses assoicated with non-ideal front end alignment ;^>
>>>
>>>Actual rolling resistance is going to be at least as great as a 4
>>>wheeler. The tires have some rolling resistance factor, which can be
>>>translated into a drag force as a fraction of the weight they are
>>>supporting. Say the coefficient of rolling resistance is 0.01; this
>>>means there will be 1lb of drag for every 100lbs on the wheel. If your
>>>two wheels have the same coefficient of rolling resistance as those on
a
>>>typical 4-wheeled conversion of similar weight, then the drag due to
>>>rolling resistance will be the same. However, the wheels in the
>>>pictures of your vehicle look like they would be significantly greater
>>>rolling resistance than those of the typical conversion.
>>>
>>>I'm not even sure that you would save significantly on the brake drag;
>>>since you have only two wheels to stop a similar weight vehicle, you
may
>>>need larger brakes and their drag may be similar to those of all 4
>>>wheels on a convnetional car. Do you use disks or drums? A typical
>>>conversion will have front disks and rear drums; most of the brake drag
>>>(and there may not be very much) will be due to the disks, so if you
>>>have disks your brake drag may be virtually the same as a tyipcal
>>>4-wheeler.
>>>
>>>Cheers,
>>>
>>>Roger.
>>>
>>
>>
>> ________________________________________
>> PeoplePC Online
>> A better way to Internet
>> http://www.peoplepc.com
>>
>>
>
>
>--
>If you send email to me, or the EVDL, that has > 4 lines of legalistic
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I
>wish with the message. By posting the message you agree that your long
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Guys,
I'm trying to compare the amount of power consumed by an electric vehicle as
compared to an ICE vehicle in a universal unit instead of an MPG equivelent
or other lame unit.
This website:
http://physics.syr.edu/courses/modules/ENERGY/ENERGY_POLICY/tables.html says
1 watt is the same as 1 joule. It also says the amount of energy contained
in 1 gallon of gasoline is 1.3X10 to the 8th power, joules or watts. If I'm
calculating this correctly, that's 130000000 (one hundred thirty million
watts in a gallon of gasoline?! Is this right?
So, we figured out that my car uses 11,700-ish watts of power at 55 mph.
That's 11700/55 giving me 213 kwh/mile. So if I drive 55 miles @ 55 mph,
I've used 11.715 kilowatts?
Let's -assume- an early 2000's Ford or GM large SUV (Expedition, Suburban,
Tahoe, Escalade or whatever) gets 14 mpg at 55 mph. That's .07 gallons per
mile. .07*130,000,000 gallons contains 9,100,000 watts of energy sooooooooo
our mythical SUV gets 9,100 kwh/mile and it uses 500,500 kw to drive 55
miles.
213 kwh/mile
9,100 kwh/mile
If that's right, it's incredible. When humans are able to quantify something
it puts it in perspective. To me, that illustrates an incredible waste,
especially when you consider that we spend even more energy trucking fuel
around to distribution points instead of just transmitting it down a wire.
IF my math is right, I'd love to run the numbers against the Honda Insight
and see what the comparison is.
Rich A.
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How do you figure that? Not counting equalization, if you tke 82Ah out,
you should only have to put about 90Ah back in. Equalization should be 1
or 2 Ah tops.
Where did you come up with the extra 60 Ah?
> I would assume this is yet another place that Peukert comes back to
> kick your butt. For example, it looks like a 150Ah Trojan J150 will
> only put out ~82Ah at 100A discharge. However, when you go to charge
> it back up you're going to need to put 150Ah plus back into it.
> Assuming the charge process is ~90% efficient (best case) you are
> looking at 50% overall efficiency. Compare that to a 55Ah Optima D34
> which still gives you 47Ah at 100A. With 90% charging efficiency
> (maybe more realistic, equalize by regulators not overcharging) you
> are looking at something more around 77% overall efficiency.
>
> Rob
>
> On Jul 11, 2007, at 3:11 AM, Peter VanDerWal wrote:
>
>> Efficiency depends on how full you fill them and how much power you
>> waste
>> equalizing them (equalization current is less than 0% efficient)
>>
>> If you keep the SOC below the 80% or so (when they start gassing) they
>> /can/ be 90+% efficient.
>>
>> However typical charging, to 100% SOC plus equalization, usually
>> works out
>> to 75% or less, depending on how old the batteries are, how often
>> and how
>> much you equalize, etc.
>>
>> Also, just to confuse things, some people talk about charging
>> efficiency
>> but only refer to columbic(sp?) efficiency, I.e. Amps in vs Amps
>> out, and
>> totally ignore the voltage difference between charge and discharge.
>>
>>> I've always heard lead-acid battery efficiency to be around 80-85%
>>> for
>>> flooded and ~90% on AGMs. I never hear at what current though.....
>>>
>>> On 7/10/07, Dan Frederiksen <[EMAIL PROTECTED]> wrote:
>>>> I seem to recall a spec sheet once saying that at only 100A the lead
>>>> acid battery was only 50% efficient. are lead acids really that
>>>> inefficient for EV use?
>>>> do they really waste that much at only 100A?
>>>>
>>>> and by implication does that mean a much more efficient battery type
>>>> like A123 can do just as good with half the capacity
>>>>
>>>>
>>>> Dan
>>>>
>>>>
>>>
>>>
>>
>>
>> --
>> If you send email to me, or the EVDL, that has > 4 lines of legalistic
>> junk at the end; then you are specifically authorizing me to do
>> whatever I
>> wish with the message. By posting the message you agree that your
>> long
>> legalistic signature is void.
>>
>
>
--
If you send email to me, or the EVDL, that has > 4 lines of legalistic
junk at the end; then you are specifically authorizing me to do whatever I
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