EV Digest 7014
Topics covered in this issue include:
1) Re: Efficiency of lead acid batteries
by "Peter VanDerWal" <[EMAIL PROTECTED]>
2) Re: Ideal EV configuration for my situation?
by "Zeke Yewdall" <[EMAIL PROTECTED]>
3) Re: Efficiency of lead acid batteries
by "Peter VanDerWal" <[EMAIL PROTECTED]>
4) Re: Ideal EV configuration for my situation?
by "Zeke Yewdall" <[EMAIL PROTECTED]>
5) Re: Efficiency of lead acid batteries
by "Peter VanDerWal" <[EMAIL PROTECTED]>
6) Re: Energy unit conversion and comparison
by "Peter VanDerWal" <[EMAIL PROTECTED]>
7) Re: Catch Phrases
by "Lawrence Rhodes" <[EMAIL PROTECTED]>
8) RE: conversion question
by "Peter VanDerWal" <[EMAIL PROTECTED]>
9) Re: a little thought problem for the list
by "Lawrence Rhodes" <[EMAIL PROTECTED]>
10) RE: Energy unit conversion and comparison - units
by "Phil Marino" <[EMAIL PROTECTED]>
11) Re: Why do I get this message SO much??? was Re:todd pc25lv dc-dc
converter specs
by Lock Hughes <[EMAIL PROTECTED]>
12) Re: Efficiency of lead acid batteries
by "Phil Marino" <[EMAIL PROTECTED]>
13) RE: conversion question
by "Tom S." <[EMAIL PROTECTED]>
14) Re: Efficiency of lead acid batteries
by Dan Frederiksen <[EMAIL PROTECTED]>
15) RE: conversion question
by "Tom S." <[EMAIL PROTECTED]>
16) Re: Efficiency of lead acid batteries
by "Evan Tuer" <[EMAIL PROTECTED]>
17) RE: conversion question
by "Michael Wendell" <[EMAIL PROTECTED]>
18) Passive (Parallel/Serial) Balancing
by Jim Davis <[EMAIL PROTECTED]>
19) Bradley GT Electric
by "Don Davidson" <[EMAIL PROTECTED]>
20) RE: conversion question
by "Tom S." <[EMAIL PROTECTED]>
21) RE: Passive (Parallel/Serial) Balancing
by "Alan Brinkman" <[EMAIL PROTECTED]>
22) RE: LED headlights
by "Bukosky, Allen" <[EMAIL PROTECTED]>
--- Begin Message ---
> 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%
>
Where did you come up with these figures?
>From what I've read, the Coulombic efficiency of Saft NiCads is almost
exactly 90%. In fact that is how Saft specifies charging them, you put
back in exactly 110% of what you took out.
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> 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.
Perhaps not, but the opposite is true. I.e. the peukert number is
effected by the internal resistance. The Peukert effect is due to several
factors, but includes the I2R losses. Higher internal resistance = higher
peukert number.
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Sorry, forgot to reset it to plain text.
>
> 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?
A string is a bunch of batteries all connected in series. So, if you have 6
volt batteries, a string would be 24 of them in series.
I'm certainly not an expert here, but my understanding is that the T-105 isn't
as desireable a batter as the T-125 or T-145 -- same AH theoretically, but they
125 or 145 keep up the voltage better under higher discharge. Which means more
plate area, which in turn means thinner plates (I think), which in turn means
they are not as good at deep cycling... But the T-105's are sort of sluggish
at more than 200A I think. Again, this is just what I've heard, no personal
experience.
Z
--- End Message ---
--- Begin Message ---
Well my thinking is, while the extra energy does increase the available
capacity slightly, it does so while causing overall efficiency to drop.
In effect the extra energy has a negative effect on total efficiency;
hence, less than 0%.
>
>
>
>>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
>> >>
>> >>
>> >
>> >
>>
>>
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>>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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>
>
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--- End Message ---
--- Begin Message ---
Well, I think if you are going to do this, then you should do it right.
Compare the well to wheels efficiency.
I.e. gasoline doesn't just appear. It starts out as cude oil burried in
the ground.
We have to use energy to get it out of the ground, and then transport it
to a refinery, then refine it, then transport it the service station, then
drive to the service station the get it, then convert it from liquid form
to mechanical energy, and then move the car.
Even when using fossil fuels (coal) electric cars are FAR more efficient.
Sorry, I can't help you with the actual units, but hopefully I've given
you something to think on.
P.s. Google "well to wheels" etc.
> 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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>
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--- Begin Message ---
Plain text is default. I'd suggest you go to that. If you send other than
plain text it will not come through. Lawrence Rhodes....
----- Original Message -----
From: "Joseph T. " <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Tuesday, July 10, 2007 5:45 PM
Subject: Re: Catch Phrases
> Switch to g-mail and select plain formatting so that we can read your
> e-mails because some of us can't read them since it's in rich
> formatting.
>
> On 7/10/07, Larry Licata <[EMAIL PROTECTED]> wrote:
> > * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
> > * ---REMAINDER OF MESSAGE TRUNCATED--- *
> > * This post contains a forbidden message format *
> > * (such as an attached file, a v-card, HTML formatting) *
> > * Lists at sjsu.edu only accept PLAIN TEXT *
> > * If your postings display this message your mail program *
> > * is not set to send PLAIN TEXT ONLY and needs adjusting *
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>
--- End Message ---
--- Begin Message ---
Actually, they have four wheeled EVs that surpass the Evette when it comes
to maneuverabilty. They have fork lifts that can spin in place, AND move
directly sideways, at any angle, etc.
Besides, the Evetts advantages are only at really low speeds, where they
don't really matter that much. Sure it might be a little easier to park,
but parking lots are designed for existing vehicles, so it's no real
advantage.
There are conversions out there that carry over 2400 lbs of batteries. I
believe the number you have mentioned for the Evett is 1600 lbs?
Any custom EV can be built to carry lots of batteries. Custom Four
wheeled ones can do it as well or better than Evette. It's simple math,
any given axle will have a maximum weight capacity. Twice as many axles
equals twice as much weight.
> 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
>
>
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Anything can be done but if you don't use at least 1/3 in battery weight you
won''t have range. I'd start with 240vdc of GC batteries (40 batteries) &
figure haw they'd be placed. Then since you have more room for batteries
(I'm sure) boat it up to near the limit. The Unimog is convertable as is
any vehicle. It'll just cost more. 300vdc system with a Zill controller
would be needed. Another possible system is to find 600vdc trolley
components and see if they fit. That is 100 golfcart batteries. You would
have to have quite an installation with battery stacking. Good luck.
Lawrence Rhodes.....
----- Original Message -----
From: "Zeke Yewdall" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Tuesday, July 10, 2007 8:20 PM
Subject: Re: a little thought problem for the list
> Some ramblings on this idea....
>
> Well, the diesel engine in that is only 110HP (unless it's one of the
> smaller variants, down to 65HP). And with that engine, it is rated to tow
> 22 tons. So, it's certainly got good gearing to go up that hill slowly
> with a very large battery bank -- 144 volt pack of L-16HC's maybe?
(2880lbs,
> 60kWh at C/20 rate) . But the question is how slow do you want to go.
> Seems like an 11" series DC or larger might be called for to get the
> sustained power you want. And a 1000A controller to feed it. Recharge
them
> during the day at the shop to get ready for going back up the hill at
> night. Going down that hill with such a heavy vehicle and no engine
braking
> is going to be scary... regen? Or, since the batteries might be full
> starting off, dynamic braking, like the locomotives have. The gearing
might
> not actually be as good as I thought, because I bet the diesel redlines
> around 2,500 or 3,000, and a series DC motor is going to want to go
faster.
> On the other hand, IIRC, top speed in 1st gear low range is around
> 0.5mphor so, so you can always downshift.... To get regen, you are
> going to need
> an AC system, a sepex DC, or some giant alternator on there... Hmmmm.
It's
> almost more like making a big electric tractor than an electric vehicle.
> Which is actually alot easier -- the little electric gorilla's can pull
cars
> around with a little 36 volt system and six Trojan T-105's.
>
> For the snowplowing, the heavier, the better. Just make sure the
batteries
> are well secured so they don't move.
>
> Z
>
> On 7/10/07, Michael Wendell <[EMAIL PROTECTED]> wrote:
> >
> >
> > okay, my boss here at the bike shop has a very nice 1978 mercedes-benz
> > unimog 406 DoKa which has developed an engine problem. i jokingly
> > suggested
> > he should convert it to electric. then i started thinking, maybe he
SHOULD
> > convert it to electric.
> >
> > so, here are the givens...
> >
> > it's a unimog 406 DoKa, and weighs almost 4 tons! please don't recommend
a
> > different donor vehicle, that's not the point.
> >
> > gross weight is probably off the charts, so no real limit on battery
> > weight,
> > but they need to fit on the flatbed, which is about 6 feet square (and
> > unfortunately 4+ feet up in the air!)
> >
> > he lives 5 miles from the shop, but it's a 1500' elevation difference.
all
> > downhill in the morning, and a steep 5 mile climb at night. as a point
of
> > reference though, i think the diesel in there now only maxes out at
25mph
> > or
> > so up that hill.
> >
> > he should also have another 10 miles per day available to run into town
or
> > take his daughter to school.
> >
> > it would probably sit for 6-10 hours during the workday, and could be
> > charging during that time.
> >
> > one additional monkeywrench... one of his goals was to use it to plow
his
> > driveway. so it should be able to run at heavy loads, pushing a plow for
a
> > few miles, in below-freezing temps.
> >
> > so, can it be done? what's the best solution?
> >
> > m.
> >
> >
> >
> >
> >
>
>
> --
> Zeke Yewdall
> Chief Electrical Engineer
> Sunflower Solar, A NewPoint Energy Company
> Cell: 720.352.2508
> Office: 303.459.0177
> FAX documents to: 720.269.1240
> [EMAIL PROTECTED]
> www.cosunflower.com
>
> CoSEIA Certified
> Certified BP Solar Installer
> National Association of Home Builders
>
> Quotable Quote
>
> "In the dark of the moon, in flying snow,
> in the dead of winter, war spreading,
> families dying, the world in danger,
> I walk the rocky hillside
> sowing clover."
>
> Wendell Berry
>
--- End Message ---
--- Begin Message ---
You got some of the units mixed up.
I'll put my comments within your post:
From: "Richard Acuti" <[EMAIL PROTECTED]>
Reply-To: ev@listproc.sjsu.edu
To: ev@listproc.sjsu.edu
Subject: Energy unit conversion and comparison
Date: Wed, 11 Jul 2007 09:50:43 -0400
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.
1 joule is equal to one watt-second., not one watt. A joule is energy, a
watt is power.
It also says the amount of
energy contained in 1 gallon of gasoline is 1.3X10 to the 8th power, joules
or watts.
Joules, NOT watts. Joules is energy. watts is power.
If I'm calculating this correctly, that's 130000000
(one hundred thirty million *joules* in a gallon of gasoline?! Is this
right?
It is, according to this site.
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.
No - it's 213 wh/mile. ( not kwh)
So if I drive 55 miles
@ 55 mph, I've used 11.715 kilowatts?
No - you've used 11700 watts for one hour. That's 11700 watt-hours, or
11.715 KWH.
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
Joules of energy, but you're on the right track.
sooooooooo our mythical SUV gets 9,100 kwh/mile and
it uses 500,500 kw to drive 55 miles.
Not quite. You've got to be careful with the units, here.
9,100,000 joules/mile = 9100,000 watt-seconds/mile X 1 hour/3600 s = 2527
watt-hr/mile
= 2.527 kwh/mile.
213 kwh/mile
9,100 kwh/mile - really 2.5 KWH/mile
If that's right, it's incredible.
While not as extreme as your original calculation, it's still over 10:1
Is your original 11,700 watts at 55 mph the power from your batteries at
that speed?
If it is, you really want to figure your energy from you wall socket. That
may be about 20% higher because of losses in the charger, and battery
inefficiencies during charging and discharge.
That would still leave you using about 1/10 the energy of the SUV. By the
way, is your EV a large SUV?
If not, it would probably be more valid to compare it's energy usage to that
of an ICE car of similar size.
Phil Marino
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.
Transmitting power down that wire can results in losses of 50 % of the
energy. I'm not defending ICE cars and gasoline, but, you should be fair
about this.
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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--- Begin Message ---
Hi Patrick
It's because more and more folks are discovering the advantages of
electric vehicles... it's a good thing!
Unfortunately, some new to the list don't read the instructions... the
message is actually self-explanatory, if you read it again.
tks
Lock
human-electric hybrid pedestrian
--- patrick DonEgan <[EMAIL PROTECTED]> wrote:
> Why do I get this message SO much???
>
> On 7/11/07, Michael Mohlere <[EMAIL PROTECTED]> wrote:
> > * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
> > * ---REMAINDER OF MESSAGE TRUNCATED--- *
> > * This post contains a forbidden message format *
> > * (such as an attached file, a v-card, HTML formatting) *
> > * Lists at sjsu.edu only accept PLAIN TEXT *
> > * If your postings display this message your mail program *
> > * is not set to send PLAIN TEXT ONLY and needs adjusting *
> > * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
> >
>
>
> --
> Patrick Ira Donegan
> TigerBody Electric Vehicles
Be smarter than spam. See how smart SpamGuard is at giving junk email the
boot with the All-new Yahoo! Mail at http://mrd.mail.yahoo.com/try_beta?.intl=ca
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--- 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 09:01:22 -0700 (MST)
Well my thinking is, while the extra energy does increase the available
capacity slightly, it does so while causing overall efficiency to drop.
In effect the extra energy has a negative effect on total efficiency;
hence, less than 0%.
I still disagree.
According to your logic, if the first half of a charge cycle was 90%
efficient, and the second half was 80% efficient, then the second half would
REALLY be less than 0 % efficient, since it reduced the overall efficiency.
So, anytime you have reduced efficiency compared to the start of a charge
cycle, you're really discharging the batteries, while using energy to do so.
Huh?
Phil
>
>
>
>>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.
>>
>
> _________________________________________________________________
> Local listings, incredible imagery, and driving directions - all in one
> place! http://maps.live.com/?wip=69&FORM=MGAC01
>
>
--
If you send email to me, or the EVDL, that has > 4 lines of legalistic
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--- Begin Message ---
Hi Peter,
In your dreans. The EVette not only maneuvers at low speeds, it turns very
well at higher speeds as well. A reporter from the Palm Beach Post took a ride
in it and wrote " Gut wrenching turns ".Its not a little easier to park, its a
lot easier to park. If a conversion has 2400lbs of batteries it most likely has
at least 3000lbs of car,5400lbs total that sounds more like a tank!
Tom Sines T
-----Original Message-----
>From: Peter VanDerWal <[EMAIL PROTECTED]>
>Sent: Jul 11, 2007 12:17 PM
>To: ev@listproc.sjsu.edu
>Subject: RE: conversion question
>
>Actually, they have four wheeled EVs that surpass the Evette when it comes
>to maneuverabilty. They have fork lifts that can spin in place, AND move
>directly sideways, at any angle, etc.
>
>Besides, the Evetts advantages are only at really low speeds, where they
>don't really matter that much. Sure it might be a little easier to park,
>but parking lots are designed for existing vehicles, so it's no real
>advantage.
>
>There are conversions out there that carry over 2400 lbs of batteries. I
>believe the number you have mentioned for the Evett is 1600 lbs?
>
>Any custom EV can be built to carry lots of batteries. Custom Four
>wheeled ones can do it as well or better than Evette. It's simple math,
>any given axle will have a maximum weight capacity. Twice as many axles
>equals twice as much weight.
>
>> 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
>>
>>
>
>
>--
>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 ---
thanks guys. was informative
might regenerative braking provide that little loosening of the sulphate
and counter that peukert accumulation so the full battery can be used?
Dan
--- End Message ---
--- Begin Message ---
Hi Phil,
Their 38" super swampers we live in Florida its a swamp, and they were sheap.
Its an experiment, different tires would of course, be much better.
Tom Sines
-----Original Message-----
>From: Phil Marino <[EMAIL PROTECTED]>
>Sent: Jul 11, 2007 9:46 AM
>To: ev@listproc.sjsu.edu
>Subject: RE: conversion question
>
>
>
>
>>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
>> >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.
>> >
>>
>>
>>________________________________________
>>PeoplePC Online
>>A better way to Internet
>>http://www.peoplepc.com
>>
>
>_________________________________________________________________
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>
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--- End Message ---
--- Begin Message ---
On 7/11/07, Peter VanDerWal <[EMAIL PROTECTED]> wrote:
> 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%
>
Where did you come up with these figures?
>From what I've read, the Coulombic efficiency of Saft NiCads is almost
exactly 90%. In fact that is how Saft specifies charging them, you put
back in exactly 110% of what you took out.
Which Saft NiCads are you talking about?
The STM5-100 most commonly used in EVs have a charge coefficient of
1.15. These are special "low maintenance" monoblocks, so I would
expect more basic batteries such as the aircraft starter type (BB600?)
to be worse from that point of view.
--- End Message ---
--- Begin Message ---
> In your dreans. The EVette not only maneuvers at low
> speeds, it turns very well at higher speeds as well.
want to prove that statement? if so, my offer still stands. attend an SCCA
autocross. if you can finish in the top 50% i'll gladly pay your entry fee.
sorry, the opinion of some local newspaper reporter, or your own exclamation
that it's fun to drive won't convince me that it actually handles well.
m.
--- End Message ---
--- Begin Message ---
I have a string of 24 (12v, gel Size 31, 100ahC/20) which is massively
out-of-balance (with individual OCV measurements ranging from 11.0 to
12.8). Individual charging with my single ~10a 12v charger is a slow
process. I don't want to put the string on my 10kw 330v charger until my
string is balanced. I am in no hurry (I have other things to work on), so
I was wondering...
Can I balance this string passively, over time?
Can I leave the series connectors in place, disconnect the pack, and add
parallel connectors to make one huge 12v amp-bucket? Would this pack then
naturally balance itself over time?
____________________________________________________________________________________
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--- Begin Message ---
Hi Michael,
I feel like Jesus , I bring good news, and you try to knock me off, although I
know some of you get it. See ya.
Tom Sines
-----Original Message-----
>From: Michael Wendell <[EMAIL PROTECTED]>
>Sent: Jul 11, 2007 11:34 AM
>To: ev@listproc.sjsu.edu
>Subject: RE: conversion question
>
>
>> In your dreans. The EVette not only maneuvers at low
>> speeds, it turns very well at higher speeds as well.
>
>want to prove that statement? if so, my offer still stands. attend an SCCA
>autocross. if you can finish in the top 50% i'll gladly pay your entry fee.
>
>sorry, the opinion of some local newspaper reporter, or your own exclamation
>that it's fun to drive won't convince me that it actually handles well.
>
>m.
>
________________________________________
PeoplePC Online
A better way to Internet
http://www.peoplepc.com
--- End Message ---
--- Begin Message ---
Jim,
If you have a series string of batteries, then add parallel jumpers to
it, you in effect have connected the negative post of a battery to the
positive post. Draw out the diagram on a piece of paper and see the
effect.
Alan Brinkman
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Jim Davis
Sent: Wednesday, July 11, 2007 8:43 AM
To: ev@listproc.sjsu.edu
Subject: Passive (Parallel/Serial) Balancing
I have a string of 24 (12v, gel Size 31, 100ahC/20) which is massively
out-of-balance (with individual OCV measurements ranging from 11.0 to
12.8). Individual charging with my single ~10a 12v charger is a slow
process. I don't want to put the string on my 10kw 330v charger until my
string is balanced. I am in no hurry (I have other things to work on),
so
I was wondering...
Can I balance this string passively, over time?
Can I leave the series connectors in place, disconnect the pack, and add
parallel connectors to make one huge 12v amp-bucket? Would this pack
then
naturally balance itself over time?
________________________________________________________________________
____________
Looking for a deal? Find great prices on flights and hotels with Yahoo!
FareChase.
http://farechase.yahoo.com/
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--- Begin Message ---
A couple of people are making molded plastic lenses for these and
similar devices. You would need one lense per LED (there are some quad
lenses out there, too).
Google "lenses for LEDs".
Allen
-----Original Message-----
From: Danny Miller [mailto:[EMAIL PROTECTED]
Sent: Wednesday, July 11, 2007 1:29 AM
To: ev@listproc.sjsu.edu
Subject: LED headlights
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 ---
