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Discussion Starter #2
Re: [EVDL] Tesla batteries (Was: EV attitudes)

> As I understand it, Tesla's pack has always been designed around
> lithium cobalt cells.
>
> In fact, they depend on the high energy density of cobalts to get
> that great 200 mile+ range, LiFePO4s such as A123s are roughly 100Wh/
> kg vs over 200Wh/kg for good LiCos.
>
> And with such a big pack, they only need modest power from the cells
> (<4C) to feed the lovely 200hp induction motor. But it also explains
> the complexity of safety systems in their pack - gotta be nice to
> LiCo cells!

Yeah, everything I've read on Tesla's site has said they're using
regular Li-Ion (cobalt-based), not A123 or the like. I've read that
they're using A123 in articles about A123 and discussion forums, but
nowhere else. As far as I know, it's always been cobalt dioxide cells
for the Tesla.

I think LiFePO4 is ultimately the better EV technology for 2 reasons:
the higher safety/stability, leading to cheaper protection systems,
and the lower materials cost, hopefully leading to affordable
mass-produced batteries. The second one is critical. LiFePO4's higher
charge/discharge rates don't really matter because if you have enough
batteries for decent range, you don't need high discharge rates, and
the grid can't handle high charge rates.

Cobalt dioxide does have much better energy density than LiFePO4, but
I think that if LiFePO4 can be manufactured much cheaper, it will win.

-Morgan

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Discussion Starter #3
Re: [EVDL] Tesla batteries (Was: EV attitudes)

I wonder how the Ni-MH systems will be competing later on with
LiFe-cells.... Energy density is about the same. Efficiency is better
for the Lions but the simplicity of Ni-MH packs...We'll see.

I think there will be several different chemistries that will "survive"
They all (Li-Co, Li-Mn, Li-Fe, Ni-MH...) have certain advantages
compared to each other.

So far I have heard that Li-Mn can be extremely cheap to make. Down to
Pb levels.

Management components in battery systems does not need to be expencive.
The 30 kWh pack will cost more than $5000 for a long time. And
management system of the cells in such pack might be just few hundred
all together.

Today situation is different since EVs are not made in quantities. I
believe conversions of existing vehicles will lead the way and that
might happen sooner than many of us believes.

China might make the 1st serious steps but then again.. they might not.
Nobody knows WTF they're up to. At least you can find hundreds of Lion
cell manufacturers in there and most of them are (more or less) crap.
They are pushing hard to get small affordable EVs on the roads...


-jukka


Morgan LaMoore kirjoitti:
>> As I understand it, Tesla's pack has always been designed around
>> lithium cobalt cells.
>>
>> In fact, they depend on the high energy density of cobalts to get
>> that great 200 mile+ range, LiFePO4s such as A123s are roughly 100Wh/
>> kg vs over 200Wh/kg for good LiCos.
>>
>> And with such a big pack, they only need modest power from the cells
>> (<4C) to feed the lovely 200hp induction motor. But it also explains
>> the complexity of safety systems in their pack - gotta be nice to
>> LiCo cells!
>
> Yeah, everything I've read on Tesla's site has said they're using
> regular Li-Ion (cobalt-based), not A123 or the like. I've read that
> they're using A123 in articles about A123 and discussion forums, but
> nowhere else. As far as I know, it's always been cobalt dioxide cells
> for the Tesla.
>
> I think LiFePO4 is ultimately the better EV technology for 2 reasons:
> the higher safety/stability, leading to cheaper protection systems,
> and the lower materials cost, hopefully leading to affordable
> mass-produced batteries. The second one is critical. LiFePO4's higher
> charge/discharge rates don't really matter because if you have enough
> batteries for decent range, you don't need high discharge rates, and
> the grid can't handle high charge rates.
>
> Cobalt dioxide does have much better energy density than LiFePO4, but
> I think that if LiFePO4 can be manufactured much cheaper, it will win.
>
> -Morgan
>
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Discussion Starter #4
Re: [EVDL] Tesla batteries (Was: EV attitudes)

I see no way NIMH will survive now. cells like the A123 ones have double =

the energy density and how many times greater power..?
and if not already then soon probably cheeper too. I dare say NIMH is dead

Dan

Jukka J=E4rvinen wrote:

>I wonder how the Ni-MH systems will be competing later on with =

>LiFe-cells.... Energy density is about the same. Efficiency is better =

>for the Lions but the simplicity of Ni-MH packs...We'll see.
>
>I think there will be several different chemistries that will "survive" =

>They all (Li-Co, Li-Mn, Li-Fe, Ni-MH...) have certain advantages =

>compared to each other.
> =

>

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Discussion Starter #5
Re: [EVDL] Tesla batteries (Was: EV attitudes)

I'd say the same thing about LiCo as well, although inertia has a way of
keeping things going for a while.

That is, assuming the battery packs don't have to be significantly bigger.

I mean, do you think the laptop manufacturers like accepting the risk that
their battery packs can burst into flames?

I think this is what to look for as far as dropping the price of LiFePo.

-----Original Message-----
I see no way NIMH will survive now. cells like the A123 ones have double
the energy density and how many times greater power..?
and if not already then soon probably cheeper too. I dare say NIMH is dead


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Discussion Starter #6
Re: [EVDL] Tesla batteries (Was: EV attitudes)

What comes to the battery technologies, I think we could draw a =

parallel with the development of mobile telephone batteries.

The first mobile phones were lead-acid driven. I remember the first =

phone that I tested and used in the 70s, it was almost the size of a =

car starter battery (and had almost the same weight...).

Mobile phones became really portable only when they got NiCd =

batteries, this was sometime in the end of 1980s. NiCd batteries had =

all their quirks, you had to discharge them fully every now and then =

etc. Normally the batteries were removable and you had one or two spare =

batteries on you if the one in use went empty (which happened quite =

often). Then came NiMh which had better usage characteristics and =

better capacity. =


The real kick for the mobile telephony came when the Li-Ion batteries =

arrived, in the mid-90s if I remember correctly. The usage time grew a =

lot and the battery is now an integral part of the phone and normally =

lasts the age of the telephone.

I see the same sequence in EV batteries. It has been slower because =

the EV batteries are much more difficult. You have tens or even =

hundreds of cells in series and the currents are much larger.

The first lead-acid commercial EVs came, when, 100 years ago? NiCd =

phase came with the French PSA cars (Peugeot, Citroen) and Renault in =

1990s. NiMh era is now. It almost started with EV-1. Then came Toyotas, =

RAV4 and Prius, etc in the beginning of 2000s.

I think that, just like in mobile phones, the next step will be the =

lithium technology, which will replace the NiMh technology. The change =

is just starting to happen. Li-Ion cars are in the laboratories and in =

proto phase, and the very first semi-commercial products like Tesla are =

being delivered. And just like in mobile phones, the Li-Ion technolgy =

will probably give EV such a range and behaviour that it might be =

acceptable for big audience, at least for city traffic.

Seppo


>----Alkuper=E4inen viesti----
>L=E4hett=E4j=E4: [email protected]
>P=E4iv=E4m=E4=E4r=E4: 10.09.2007 13:27
>Vastaanottaja: "Electric Vehicle Discussion List"<[email protected]>
>Aihe: Re: [EVDL] Tesla batteries (Was: EV attitudes)
>
>I see no way NIMH will survive now. cells like the A123 ones have =

double =

>the energy density and how many times greater power..?
>and if not already then soon probably cheeper too. I dare say NIMH is =

dead
>
>Dan
>
>Jukka J=E4rvinen wrote:
>
>>I wonder how the Ni-MH systems will be competing later on with =

>>LiFe-cells.... Energy density is about the same. Efficiency is =

better =

>>for the Lions but the simplicity of Ni-MH packs...We'll see.
>>
>>I think there will be several different chemistries that will =

"survive" =

>>They all (Li-Co, Li-Mn, Li-Fe, Ni-MH...) have certain advantages =

>>compared to each other.
>> =

>>
>
>_______________________________________________
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>http://lists.sjsu.edu/mailman/listinfo/ev
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Discussion Starter #7
Re: [EVDL] Tesla batteries (Was: EV attitudes)

Seppo Lindborg wrote:
> What comes to the battery technologies, I think we could draw a
> parallel with the development of mobile telephone batteries.
>
> The first mobile phones were lead-acid driven...
> Mobile phones became really portable only when they got NiCd batteries
> Then came NiMh which had better usage characteristics and capacity...
> The real kick for the mobile telephony came when the Li-Ion batteries
> arrived...

The batteries weren't driving these changes; it was the electronics. The
early mobile phones used vacuum tubes! This is why they were so large,
and required so much power. They also needed quite powerful
transmitters, as the distance to the nearest repeater was very large (up
to 100 miles).

The later phones used discrete transistors, which took much less power.
This made it practical to use nicads. But they still needed powerful
transmitters, because the distance to the repeaters was so large (30
miles or more).

Nimh cells didn't get used until after the cell-phone technology hit.
Transmitter power is far lower, since there are vastly more repeaters;
rarely do they have to transmit more than 5-6 miles.

Lithium cells are basically just allowing smaller phones. It has become
fashionable to have very tiny phones; so small that they are harder to
use and more easily damaged.

Throughout all this time, the trend has been for the phone to use less
and less power. This has allowed the battery size to keep going down.
All that the more advanced battery technologies are doing is allowing
smaller phones, and more non-phone features to be crowded in.

This evolution is less likely to happen with automobiles, because they
require a substantial amount of power, proportional to the weight of the
vehicle. There are no technological ways to reduce the power
requirements substantially -- just small evolutionary improvements.

What fundamentally matters for EV batteries is their cost per mile. To
ever be successful in the market, EVs will have to compete on a economic
basis with ICEs. This can't happen with "bleeding edge" high-tech
proprietary batteries. It will have to be done with batteries that are
inexpensive, easy to produce, and low enough tech to be produced by
dozens of companies around the world.
--
Ring the bells that still can ring
Forget the perfect offering
There is a crack in everything
That's how the light gets in -- Leonard Cohen
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net

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Discussion Starter #9
Re: [EVDL] Tesla batteries (Was: EV attitudes)

Zeke Yewdall <[email protected]> wrote:
> Well, there's always the hyper car... why should a vehicle glider
> weigh 2,000 lbs. Why not use carbon fiber and let it weigh 400lbs for
> the same thing. I'm sure you've all ready Amory Lovin's writings on
> this... but this is what could be the equivalent of the new
> electronics in cell phones. Hey, I'm sure that some people freaked
> out when they switched from wood to steel for cars... might be time to
> stop using steel now...
> ...

That's what the solar car project does. The only metal in the frame is
the suspension and the roll bar; the rest is all carbon honeycomb. The
entire car, including motor and 30kg of batteries, is only 400
pounds. The downside is that the carbon honeycomb is really expensive;
thousands of dollars for just the sheets of raw material.

-Morgan

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Discussion Starter #10
Re: [EVDL] Tesla batteries (Was: EV attitudes)

Economy only gives you so much. You have to still have a certain minimum
performance, something lead-acid strains to do (with conversions at least).
It's the same reason people chose not to buy Yugos if they could afford not
to. So cost per mile doesn't mean much if you're talking about the
difference between being able to go 20 miles on a charge (or less in cold
temperatures) vs. 80.

-----Original Message-----
What fundamentally matters for EV batteries is their cost per mile. To
ever be successful in the market, EVs will have to compete on a economic
basis with ICEs. This can't happen with "bleeding edge" high-tech
proprietary batteries. It will have to be done with batteries that are
inexpensive, easy to produce, and low enough tech to be produced by
dozens of companies around the world.

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Discussion Starter #11
Re: [EVDL] Tesla batteries (Was: EV attitudes)

Kind of a philosophical debate here. Both are unobtainium (at least now)
and we could also discuss the advantages of warp- versus light speed.

Fact is - that NIMH is a proven technology that could be made available
tomorrow - and would solve a lot of not only my problems.

Let me say it in Chevron's own words:

"One of the environmental concerns we all share is global climate change.
We recognize that the use of fossil fuels has contributed to an increase
in greenhouse gases - mainly carbon dioxide and methane - in the earth's
atmosphere, and we are doing something about it." (from the chevron.com
home page)

Well guys - you could start licensing your NIMH technology.

But - since that is all just marketing babble - all we CAN do is discuss
the differences between unobtainium and, well, unobtainium.

Michaela


> I see no way NIMH will survive now. cells like the A123 ones have double
> the energy density and how many times greater power..?
> and if not already then soon probably cheeper too. I dare say NIMH is dead
>
> Dan


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Discussion Starter #12
Re: [EVDL] Tesla batteries (Was: EV attitudes)

Zeke Yewdall <[email protected]> wrote:
>> Well, there's always the hyper car... why should a vehicle glider
>> weigh 2,000 lbs? Why not use carbon fiber and let it weigh 400lbs
>> for the same thing.

Morgan LaMoore wrote:
> That's what the solar car project does. The only metal in the frame is
> the suspension and the roll bar; the rest is all carbon honeycomb. The
> entire car, including motor and 30kg of batteries, is only 400
> pounds. The downside is that the carbon honeycomb is really expensive;
> thousands of dollars for just the sheets of raw material.

Yes, price is the killer with carbon fiber. Both labor and materials are
far more expensive than stamped steel.

But it certainly works! Our Sunrise chassis and body only weigh about
400 lbs, and that's for a full-sized 4-seat car! We're making it a kit
car, so if the builder wants to put in the effort, he can get this kind
of weight savings, too.
--
Ring the bells that still can ring
Forget the perfect offering
There is a crack in everything
That's how the light gets in -- Leonard Cohen
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net

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Discussion Starter #13
Re: [EVDL] Tesla batteries (Was: EV attitudes)

[email protected] wrote:
> Economy only gives you so much. You have to still have a certain
> minimum performance, something lead-acid strains to do (with
> conversions at least).

Yes; exactly. With a conversion, lead-acid can give you great
performance (White Zombie, Current Eliminator, etc.) but the tradeoff is
poor range. Or, you can get great range (Red Beastie, Sundancer, etc.)
but trade off performance to get it. If you try to get both at once, you
wind up with an EV with mediocre range and performance.

The key is *not* to build conversions, but instead build it as an EV
from the ground up. Then it *can* offer both range and performance, even
with lowly lead-acid batteries.

If you take 1000 lbs out of the weight of a car, and put it back as more
batteries, you now have a vehicle that weighs the same but has 3 times
the battery capacity, and thus 3 times the range. For performance,
you've got 3 times the peak power that you would have had with an EV
conversion.

Put another way, you can go from an EV conversion that has a range of 50
miles and does 0-60 mph in 18 seconds, to an EV with a range of 150
miles and 0-60 mph in 6 seconds. Sure; you can beat it with advanced
batteries for 10 times the cost. But for the average Joe, cost is more
important. This EV will do everything he does with his present car; and
cheaper too! Now you're talking his language!

Can we pull it off? I don't know... but I'm certainly going to try!
--
Ring the bells that still can ring
Forget the perfect offering
There is a crack in everything
That's how the light gets in -- Leonard Cohen
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net

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Discussion Starter #14
Re: [EVDL] Tesla batteries (Was: EV attitudes)

Lee and list
You know you are right Lee. Keep working on the
sunrise.
Everybody else on the list send Lee money and
encouragement he is doing good work for us all and he
is the best chance we have of getting over the
problems inherent in the EV as real world
transportation.

kEVs


--- Lee Hart <[email protected]> wrote:

> [email protected] wrote:
> > Economy only gives you so much. You have to still
> have a certain
> > minimum performance, something lead-acid strains
> to do (with
> > conversions at least).
>
> Yes; exactly. With a conversion, lead-acid can give
> you great
> performance (White Zombie, Current Eliminator, etc.)
> but the tradeoff is
> poor range. Or, you can get great range (Red
> Beastie, Sundancer, etc.)
> but trade off performance to get it. If you try to
> get both at once, you
> wind up with an EV with mediocre range and
> performance.
>
> The key is *not* to build conversions, but instead
> build it as an EV
> from the ground up. Then it *can* offer both range
> and performance, even
> with lowly lead-acid batteries.
>
> If you take 1000 lbs out of the weight of a car, and
> put it back as more
> batteries, you now have a vehicle that weighs the
> same but has 3 times
> the battery capacity, and thus 3 times the range.
> For performance,
> you've got 3 times the peak power that you would
> have had with an EV
> conversion.
>
> Put another way, you can go from an EV conversion
> that has a range of 50
> miles and does 0-60 mph in 18 seconds, to an EV with
> a range of 150
> miles and 0-60 mph in 6 seconds. Sure; you can beat
> it with advanced
> batteries for 10 times the cost. But for the average
> Joe, cost is more
> important. This EV will do everything he does with
> his present car; and
> cheaper too! Now you're talking his language!
>
> Can we pull it off? I don't know... but I'm
> certainly going to try!
> --
> Ring the bells that still can ring
> Forget the perfect offering
> There is a crack in everything
> That's how the light gets in -- Leonard Cohen
> --
> Lee A. Hart, 814 8th Ave N, Sartell MN 56377,
> leeahart_at_earthlink.net
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
>




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Discussion Starter #15
Re: [EVDL] Tesla batteries (Was: EV attitudes)

well actually, as I see it, with these new promising lifepo prices of
around 680$/kWh, high performance lithium is now cheaper than lead acid
given the better peukert and lifespan. although that's cell cost only I
think that's a fact that's worth mulling over in the mind a few times.

further, I think it would be a mighty neat trick to be able to reduce a
typical car by 1000lbs if it has to carry a ton of lead acid. Maybe you
are thinking about a more lighter construction philosophy in which case
you actually need lighter batteries too unless you propose an expensive
carbon fiber construction or other semi exotic materials.
I agree we can live well with much lighter vehicles but that's
irrespective of whether it's electric or gas. so conversion is not the
problem. lead acid is.

Dan


Lee Hart wrote:

>The key is *not* to build conversions, but instead build it as an EV
>from the ground up. Then it *can* offer both range and performance, even
>with lowly lead-acid batteries.
>
>If you take 1000 lbs out of the weight of a car, and put it back as more
>batteries, you now have a vehicle that weighs the same but has 3 times
>the battery capacity, and thus 3 times the range.
>Sure; you can beat it with advanced
>batteries for 10 times the cost. But for the average Joe, cost is more
>important. This EV will do everything he does with his present car; and
>cheaper too! Now you're talking his language!
>
>Can we pull it off? I don't know... but I'm certainly going to try!
>
>

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Discussion Starter #16
Re: [EVDL] Tesla batteries (Was: EV attitudes)

keith vansickle wrote:
> Lee and list
> You know you are right Lee. Keep working on the
> sunrise.
> Everybody else on the list send Lee money and
> encouragement he is doing good work for us all and he
> is the best chance we have of getting over the
> problems inherent in the EV as real world
> transportation.
>
> kEVs


You can even donate via PayPal, as many of us on this
list do!

John in Sylmar, CA
PV EV

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Discussion Starter #17
Re: [EVDL] Tesla batteries (Was: EV attitudes)

Michaela Merz wrote:

> Fact is - that NIMH is a proven technology that could be made
> available tomorrow [...]

> But - since that is all just marketing babble - all we CAN do
> is discuss the differences between unobtainium and, well,
> unobtainium.

Do note that large format NiMH is available right now from Cobasys. It
is costly, but not unobtainium.

Cheers,

Roger

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Discussion Starter #18
Re: [EVDL] Tesla batteries (Was: EV attitudes)

Roger and All,
I have also heard that Nilar here in Colorado has plans to do larger NiMH cells, and claims to have a way of avoiding patent infringements!
Suck Amps,
BB

http://www.nilar.com/



>Date: Tue, 11 Sep 2007 14:13:10 -0700
>From: "Roger Stockton"
>Subject: Re: [EVDL] Tesla batteries (Was: EV attitudes)
>
>Michaela Merz wrote:
>
>> Fact is - that NIMH is a proven technology that could be made
>> available tomorrow [...]
>
>> But - since that is all just marketing babble - all we CAN do
>> is discuss the differences between unobtainium and, well,
>> unobtainium.
>
>Do note that large format NiMH is available right now from Cobasys. It
>is costly, but not unobtainium.
>
>Cheers,
>
>Roger

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