EV Digest 6676
Topics covered in this issue include:
1) Re: Buying new batteries, maybe more
by "Matt Kenigson" <[EMAIL PROTECTED]>
2) Re: Zilla question
by [EMAIL PROTECTED] (Dana Havranek)
3) RE: Printing cars (was: how businesses work)
by "Randy Burleson" <[EMAIL PROTECTED]>
4) RE: Printing cars (was: how businesses work)
by "damon henry" <[EMAIL PROTECTED]>
5) Re: Jacob has Tagged you! :)
by Steve Condie <[EMAIL PROTECTED]>
6) Golfcart on streets.
by "Lawrence Rhodes" <[EMAIL PROTECTED]>
7) Canned Response Letter from GM on the Volt
by Chip Gribben <[EMAIL PROTECTED]>
8) Re: Warp9 max motor voltage?
by <[EMAIL PROTECTED]>
9) Re: Printing cars (was: how businesses work)
by Eric Olson <[EMAIL PROTECTED]>
10) Re: Who Killed the Electric Car
by <[EMAIL PROTECTED]>
11) Electric lawn mower
by <[EMAIL PROTECTED]>
12) Re: Killacycle in DesignFax online
by "Ryan Stotts" <[EMAIL PROTECTED]>
13) New 12v Lithium battery?
by "Ryan Stotts" <[EMAIL PROTECTED]>
14) evparts FAQ!
by David Brandt <[EMAIL PROTECTED]>
15) Re: Killacycle in DesignFax online
by [EMAIL PROTECTED]
16) Re: Transmission Choice
by "Michael Perry" <[EMAIL PROTECTED]>
17) Re: Excellent GM Volt video
by Jeff Shanab <[EMAIL PROTECTED]>
18) Re: Excellent GM Volt video
by "Ryan Stotts" <[EMAIL PROTECTED]>
19) The electric go cart lives, broken axle.
by "Martin Klingensmith" <[EMAIL PROTECTED]>
20) Lithium batteries (was: Re: Excellent GM Volt video)
by Ian Hooper <[EMAIL PROTECTED]>
21) Re: Printing cars (was: how businesses work)
by "jerryd" <[EMAIL PROTECTED]>
22) KillaCycle pack voltage (was: Killacycle in DesignFax online
by Bill Dube <[EMAIL PROTECTED]>
23) Re: Lithium batteries & safety
by "Osmo S." <[EMAIL PROTECTED]>
24) CURTIS CONTROLLER FIRES - AMMETER ACCURACY was Re: fuse size
by robert mat <[EMAIL PROTECTED]>
25) Last Call Lee Hart Battery balancer mail thread
by [EMAIL PROTECTED]
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Hi John,
Yes.
It works fine.
I have had a couple different cables in there.
Install the black thingy.
Be careful with the sensor inputs to the hairball.
Dana
-------------- Original message ----------------------
From: "John O'Connor" <[EMAIL PROTECTED]>
> I'm actually wiring up my conversion and I have a question for those
> familiar with Zilla setups. The cat 5 cable for connecting the Zilla
> to the the hairball that came from Otmar is a bit on the short side.
>
> Can I replace it with a custom cut length of cat 5 installing that
> "black thing" from the original cable on the new cable.
>
> What is that black thing anyway?
>
> John
>
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> Although it's not quite here yet, the cost of material production will
> eventually get very close to free with open source projects like this:
> http://www.reprap.org
That seems a pretty big leap. My employer uses SLA for
rapid-prototyping, and it is very quick and effective, but also quite
costly. Sure, price will inevitably come down, but I doubt it will ever
reach the point of true commodity.
> I can imagine a large version of this that could print the body
> and (most) non-electrical parts for a Sunrise or FreedomEV.
What if Lee and Jerry actually want to charge for their products,
instead of giving them away? RepRap doesn't lend itself to layered
composites, but I could see using the resultant part as the core, and
laminating layers atop it... the process itself is feasible, even if the
cost and ownership are not.
RepRap is cool technology... start saving your replicator rations
(obscure Star Trek reference). :p
Randii
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RepRap is cool technology... start saving your replicator rations
(obscure Star Trek reference). :p
Randii
Not obscure on this list.
_________________________________________________________________
Dont quit your job Take Classes Online and Earn your Degree in 1 year.
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It seems that a golfcart can be driven on city street in 25mph zones in
California with an Off Highway permit if the city has a golf cart
transportation plan. Below is from the California Vehicle Code. I also saw
a person with a Parcar with reversed back seats, turnsignals, seatbelts &
lights. It is capable of 20mph & he is driving it all over San Francisco.
Lawrence Rhodes........
Streets and Highways Code
1961 A city or county that adopts a golf cart transportation plan shall
adopt all of the following as part of the plan:
(a) Minimum design criteria for golf carts, that may include, but not be
limited to, headlights, turn signals, safety devices, mirrors, brake lights,
windshields, and other devices. The criteria may include requirements for
seatbelts and a covered passenger compartment.
(b) A permit process for golf carts that requires permitted golf carts to
meet minimum design criteria adopted pursuant to subdivision (a). The permit
process may include, but not be limited to, permit posting, permit renewal,
operator education, and other related matters.
(c) Minimum safety criteria for golf cart operators, including, but not
limited to, requirements relating to golf cart maintenance and golf cart
safety. Operators shall be required to possess a valid California driver's
license and to comply with the financial responsibility requirements
established pursuant to Chapter 1 (commencing with Section 16000) of
Division 7.
(d) (1) Restrictions limiting the operation of golf carts to separated golf
cart lanes on those roadways identified in the transportation plan, and
allowing only those golf carts that have been retrofitted with the safety
equipment specified in the plan to be operated on separated golf cart lanes
of approved roadways in the plan area.
(2) Any person operating a golf cart in the plan area in violation of this
subdivision is guilty of an infraction punishable by a fine not exceeding
one hundred dollars ($100).
(Amended Sec. 1.5, Ch. 536, Stats. 1997. Effective January 1, 1998.)
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Thank you for contacting the Chevrolet Customer Assistance Center.
We appreciate you taking the time to write us in regards to the Volt.
Thank you for your interest in the Chevrolet Volt concept electric
vehicle. The Volt, for most daily commutes, could nearly eliminate
going to the gas station altogether and greatly reduce tailpipe
emissions. It employs GM’s new E-flex system, which is a flexible
propulsion system that produces electricity and fits into a common
chassis. Its on-board generator is capable of converting and storing
electricity from energy carriers such as hydrogen, gasoline, E85, bio-
diesel and diesel.
The E-flex system is being developed for production intent. Core
engineering and manufacturing feasibility studies are underway.
However, we are not making a production announcement, nor will we
predict when the Chevrolet Volt will come to market. Battery
technology is maturing quickly. Consequently, we are accelerating
engineering development of the E-flex technology, which will enable
us to take advantage of advances in batteries as they occur. When the
battery is ready, we will be, too.
If you should need to contact us in the future, simply reply to this
message [EMAIL PROTECTED] or call our Chevrolet Customer Assistance
Center at 1-800-222-1020. Customer Relationship Specialists are
available Monday through Friday from 8:00 a.m. to 11:00 p.m., Eastern
Time.
For more information regarding the maintenance and care of your
vehicle [yes, my EV-1 is shorter then it used to be. Can you help?],
please visit www.mygmlink.com. This free online service offers
vehicle and ownership-related information and tools tailored to your
specific Chevrolet.
Again, thank you for contacting Chevrolet.
Sincerely,
The Chevrolet Consumer Support Team
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When I say ahead I mean as the direction that the motor is turning the brush
bell housing is turned the other, just like a gas car motor. A good way to
check is to run the motor on a 12volt battery and try both directions , motor
will run faster with the advanced timing.
Steve Clunn
>
> From: <[EMAIL PROTECTED]>
> Date: 2007/04/18 Wed AM 08:52:21 EDT
> To: <ev@listproc.sjsu.edu>
> Subject: Re: Warp9 max motor voltage?
>
>
> >
> > > I have an older Warp 9 (serial number 2) i
> > >
> If its gray You should also check to see if the timing is advanced . If the
> bolts from the field and armature line up in a straight line then it's not
> advanced , should be about 3/4 of an inch off with armature bolt ahead of
> field bolt while looking at the tail shaft.
> Steve Clunn
>
> > > Thanks for your time,
> > >
> > > - Steven Ciciora
> > >
> > > __________________________________________________
> > > Do You Yahoo!?
> > > Tired of spam? Yahoo! Mail has the best spam protection around
> > > http://mail.yahoo.com
> > >
> > >
> >
>
>
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Randy Burleson wrote:
Although it's not quite here yet, the cost of material production will
eventually get very close to free with open source projects like this:
http://www.reprap.org
That seems a pretty big leap. My employer uses SLA for
rapid-prototyping, and it is very quick and effective, but also quite
costly. Sure, price will inevitably come down, but I doubt it will ever
reach the point of true commodity.
Reading through the reprap webpages, their view is different, and they
are aiming to make it a commodity. Of course your predictions are as
valid as theirs until/if it happens.
I can imagine a large version of this that could print the body
and (most) non-electrical parts for a Sunrise or FreedomEV.
What if Lee and Jerry actually want to charge for their products,
instead of giving them away?
Good point, I was mostly referring to the fact that Lee has mentioned
selling the plans for the Sunrise before selling full EVs. I have no
problem if they or anyone else want to sell part or a whole EV for a profit.
The main point is that "if" fabricating becomes cheap and easy,
successful open source portions of an EV are more likely -- the progress
of open source software, GNU, Linux, the Cathedral and the Bazaar, etc.
becomes more relevant. At that point businesses selling support and
service for things will still be needed by some -- similar to IBM and
others selling support for linux.
RepRap doesn't lend itself to layered
composites, but I could see using the resultant part as the core, and
laminating layers atop it..
Ah, thanks for the ideas. I'll have to do some research on materials.
. the process itself is feasible, even if the
cost and ownership are not.
I disagree. There is plenty of good and useful open source software
around even though each copy is not sold. I guess our main disagreement
is dependent on whether fabrication capabilities will become a commodity.
RepRap is cool technology... start saving your replicator rations
(obscure Star Trek reference). :p
No kidding :) Next I'll have to print out my space ship (EV of course :)
Eric
Randii
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Bob. I just tried to call and order one. It seems that the call center that
you get is deturmed by were you call from
and not all centers have the same movies for sale,also you must be a member
to buy one, so, NO LUCK
OL_Joe still with 5 Pass.cars
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I got one lawn customer who thinks once or twice a year is all their lawn needs
to be cut . Its a great lawn to show off the power of my electric mower, with a
8 inch net gain motor , and curtis controller , I have never truned it all the
way up not even in this video. I videoed the last 2 cuttings and put it up on
youtube .
www.youtube.com/watch?v=OqiAGU5cLjY&mode=user&search=
Steve Clunn
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First I've seen of this page:
http://www.a123racing.com/html/killacycle.html
That DesignFax article says 375v and the A123 page says 380v?
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What's that case made out of?
http://ev-battery.com/Batteries/004.jpg
Check out the specs:
http://ev-battery.com/Batteries/PricesDoc.html
http://ev-battery.com/
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Hello, list. With all the EV FAQ’s popping up all over the web (such as Jerry
Halsteads very nice new addition to his EV site), I’d like to remind everybody
about the FAQ at evparts.com. It is quite extensive, and while some of the
questions have not yet been answered, most of them have. This is thanks to the
people on this list.
Some have called this FAQ ‘dated’ but honestly, over the years, only the names
have changed. The questions and answers have stayed pretty much the same. I
have recently checked up to the controller section, and everything seems
reasonable. I did copy a list of lithium battery info. to a different
question, but on the whole, only minor editing was required. I'll finish with
the rest within a couple of days.
I am currently the evparts.com FAQ editor. Within the last year, a LOT of spam
has started to come through the faqeditor address. As a result, if there have
been any legitimate requests come through, they have likely been rejected by my
(yahoo’s) spam filters. The volume is incredible. I have sent multiple
messages to the evparts.com web guys, but have had no response. Therefore, if
you have an answer or a question to add, or any suggestions to make, please
email me directly instead of using the faqeditor link.
I'd like to prevent dead links in the FAQ, so if you spot any, contact me.
Thanks!
David Brandt
__________________________________________________
Do You Yahoo!?
Tired of spam? Yahoo! Mail has the best spam protection around
http://mail.yahoo.com
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In a message dated 4/18/07 6:26:36 PM Pacific Daylight Time,
[EMAIL PROTECTED] writes:
<< Subj: Re: Killacycle in DesignFax online
Date: 4/18/07 6:26:36 PM Pacific Daylight Time
From: [EMAIL PROTECTED] (Ryan Stotts)
Sender: [EMAIL PROTECTED]
Reply-to: ev@listproc.sjsu.edu
To: ev@listproc.sjsu.edu
First I've seen of this page:
http://www.a123racing.com/html/killacycle.html
That DesignFax article says 375v and the A123 page says 380v >>
I saw 394 after a charge cycle.Dennis Berube </HTML>
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That tranny is as strong as the ones they put in cars of the era... similar
strength to the Toyota auto. The first EV locally (1970) was a Toyota car.
It twisted a couple drive lines (started in 3rd or 4th instead of 1st or
2nd gear) but they had no probs w/ the tranny. (Contact controller &, if I
recall, an aircraft starter.)
Of course, that's assuming the tranny is still in good shape. I know a
couple of those old trucks w/ 200-300K on the clock.
----- Original Message -----
From: "Pestka, Dennis J" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Wednesday, April 18, 2007 4:10 AM
Subject: Transmission Choice
> I'm considering using a different transmission in my 1965 Datsun pickup
> conversion.
> Dennis
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I think we will see a dramatic drop in pricing on the lithium phosphate
cells in the next few months.
Hopefully i will have the rest of my welder and have my balance boards
done in time.
Yesterdays initial quote was for an sample quantiy of a few hundred
high energy 2.2A 18650's 1.5ah for $6/cell, 2000cycles to 80%
high power 22A cont no peak listed yet., 1.2ah for $5 1500 cycles
to 70% (humm :-( )
and high energy 26650's 3.1ah 6.2A cont. 15.5Apeak at $13/cell.
Waiting for pricing on 48A cont 26650's
All available in June
I did some design and it looks good for 120 cells in a group 24
footprint.
2x6x10 = 6.4V @ 144ah
6x2x10 = 19.2V@ 48ah
3x4x10 = 9.6V @ 96ah
4x3x10 = 12.8V @ 72ah
all are about 922Wh per module and a bare cell cost of under $1500
I am trying to get All 4 configurations possible in one unit,
change interconnects and some jumpers.(Authorized Personel Only!)
I know this is still too high, but it is preliminary pricing.
But a compromise could be 168 of the 18650's that would be $840 in bare
cell cost for the high power and would give less const amps(around 600)
but only 645wh :-(
ie 12.8V @ 50Ah
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high energy 2.2A 18650's 1.5ah for $6/cell, 2000cycles to 80%
I got the impression from the video that the GM/Tesla price is
$2/cell. If that's the case, then that means the batteries CAN BE had
at that price and the manufacturer is still making a profit.
My favorite part of the video is at 23:33, when he reminisces a bit
and notes how GM has no involvement/participation in the acquisition
of oil or the production of gasoline. He dreamily says 'it is
relativity easy to duplicate the manufacturing process(lithium)',
'setting up a lithium ion plant in the states, that's not a very big
deal'. Remember he was CEO of Exide from 1998 to 2002. GM is at the
mercy of cheap fuel being a commodity. If they had an unlimited
supply of locally manufactured batteries..
http://en.wikipedia.org/wiki/Robert_Lutz
So does GM build their own batteries or does he get his old contacts
from Exide to do it? Or get A123 to crank up their production? Is
A123 running at capacity? They need two or three assembly lines like
they already have?
The Volt is a good idea because it is a start. It wouldn't take much
for it to be fully electric.
Imagine a full electric Prius? Take the RAV4EV drive train and use a
modern pack.. Or a current UQM motor.
Once the Tesla's get on the road and are proven; I think things will
really start to change. It has a relatively small pack too doesn't
it? What if it had a pack that was double or triple that size? How
about the range then?
Some lithium company as a promotion and a proof of concept needs to
wire up the biggest pack the world has ever seen and drive ~1,000+
miles on a single charge just to put an end to limited range issues.
Get the Killacycle in 7's. What could the Current Eliminator and the
new truck, and White Zombie run on A123's? Are A123's king of the
world and nothing else compares? They have no competition?
What if we pooled money together and acquired a pack that could be
passed around from vehicle to vehicle just to set records? What if
A123 could loan or lease a pack for this purpose? As a promotional,
marketing, tax write off type of event.
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On 19/04/2007, at 11:46 AM, Ryan Stotts wrote:
high energy 2.2A 18650's 1.5ah for $6/cell, 2000cycles to 80%
I got the impression from the video that the GM/Tesla price is
$2/cell. If that's the case, then that means the batteries CAN BE had
at that price and the manufacturer is still making a profit.
For reference, the latest price list I got from ThunderSky puts their
lithiums at US$0.50/Wh - and that's sample quantity pricing.
Once the Tesla's get on the road and are proven; I think things will
really start to change. It has a relatively small pack too doesn't
it? What if it had a pack that was double or triple that size? How
about the range then?
IIRC the Tesla pack contains 6831x 18650 cells, or about 50kWh and
400kgs. I tend to think this is a pretty big pack for an EV (enabling
the 250 mile range), and IMHO having 1/3rd of the vehicle weight in
batteries is about as much as you'd want in a production vehicle.
That said, lithium batteries really are getting better all the time -
I notice you can get 18650 cells over 220Wh/kg now (e.g http://
www.megabatteries.com/item_details.asp?id=14348&cat_id=51). 400kg
worth of those would be approaching 100kWh! (But would cost more than
a house..)
Get the Killacycle in 7's. What could the Current Eliminator and the
new truck, and White Zombie run on A123's? Are A123's king of the
world and nothing else compares? They have no competition?
I've never come across any other cells with discharge rates as high
as the A123s, no.. Plenty of LiPos out there can do 40C though, e.g
http://www.kokam.com/product/product_pdf/rc_070226/
SLPB11043140H_4800mAh_Grade.pdf - still a whole lot of power, and
they have almost 50% higher energy density than the A123s (155Wh/kg
vs 108Wh/kg). Arguably that's more important than 100C discharge
rates! But, once again, prohibitively expensive for EV-sized packs.
-Ian
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Hi Eric and All,
----- Original Message Follows -----
From: Eric Olson <[EMAIL PROTECTED]>
To: ev@listproc.sjsu.edu, [EMAIL PROTECTED]
Subject: Re: Printing cars (was: how businesses work)
Date: Wed, 18 Apr 2007 19:14:39 -0500
>Randy Burleson wrote:
>>> Although it's not quite here yet, the cost of material
>> production will
>>> eventually get very close to free with open source
>> projects like this:
>>> http://www.reprap.org
>> That seems a pretty big leap. My employer uses SLA for
>> rapid-prototyping, and it is very quick and effective,
>> but also quite costly. Sure, price will inevitably come
>> down, but I doubt it will ever reach the point of true
>commodity.
>
>Reading through the reprap webpages, their view is
>different, and they are aiming to make it a commodity. Of
>course your predictions are as valid as theirs until/if it
>happens.
These are great products that will eventually become
a common way to make many products on demand.
Just full size EV's will not be one unless materials
greatly improve. Why is you need fibers to increase the
resin's strength. A random fiber orientation won't do as it
needs too much resin and why chooper gun FG is so weak.
Also most lightweight, strong composites are much
stronger if you use a core.
As it takes just 8 hrs or so to do a Freedom EV
body/chassis in the hand layup method, labor costs are not
that much and gives a much better job, lighter in weight.
If you did try to print one, you would have to use a
mold to get a quality outside surface or your saving will be
ate up by finishing labor.
I've already given away all the details on the Freedom
EV construction so if anyone wants to, they could read all
my old posts and duplicate it.
>
>>
>>> I can imagine a large version of this that could print
>>> the body and (most) non-electrical parts for a Sunrise
>> or FreedomEV. What if Lee and Jerry actually want to
>> charge for their products, instead of giving them away?
>
>Good point, I was mostly referring to the fact that Lee has
>mentioned selling the plans for the Sunrise before selling
>full EVs. I have no problem if they or anyone else want
>to sell part or a whole EV for a profit.
Plans really isn't the right word here, more like
assemble instructions as there is not a chance in hell to
build one from scratch as it would take several thousand
hrs. Much cheaper to by the Sunrise kit or a finished
Freedom EV unless your labor is worth less than a couple
bucks/hr.
Doing a composite vehicle in composites from scratch
is only realistic if you are building a lot of them due to
the work building the male mold. Or pop a mold off any car
you like where you can use the same windshield, doors, ect.
Jerry Dycus
>
>The main point is that "if" fabricating becomes cheap and
>easy, successful open source portions of an EV are more
>likely -- the progress of open source software, GNU, Linux
>, the Cathedral and the Bazaar, etc. becomes more
>relevant. At that point businesses selling support and
>service for things will still be needed by some -- similar
>to IBM and others selling support for linux.
>
>> RepRap doesn't lend itself to layered
>> composites, but I could see using the resultant part as
>> the core, and laminating layers atop it..
>
>Ah, thanks for the ideas. I'll have to do some research on
>materials.
>
>>. the process itself is feasible, even if the
>> cost and ownership are not.
>
>I disagree. There is plenty of good and useful open source
>software around even though each copy is not sold. I
>guess our main disagreement is dependent on whether
>fabrication capabilities will become a commodity.
>
>>
>> RepRap is cool technology... start saving your replicator
>> rations (obscure Star Trek reference). :p
>
>No kidding :) Next I'll have to print out my space ship (EV
>of course :)
>
>Eric
>
>>
>> Randii
>>
>>
>>
>
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Here is a breakdown of the what a voltmeter will read on the
KillaCycle battery pack:
Under charge: As much as 410 volts (~3.7 volts per cell)
Just after charge, the voltage will slowly drift down to 374 volts.
(3.4 volts per cell) This takes quite awhile, much like the time it
takes for a surface charge to come off a lead-acid battery. We
sometimes help the pack along by connecting a modest resistive load
briefly. We do this because it is not wise to connect up the Zilla to
any more voltage than you need to.
By the time the bike pulls up to the staging lanes after the trip
from the pits, the pack is at about 375 volts. After the burn-out, it
is slightly less than that. Once you have taken any significant
current out of the pack, the cells drop to 3.3 volts each and they
stay there. The pack voltage is somewhere between 374 and 363 volts
at the starting line, depending on how awesome a burn-out Scotty has
chosen to do. :-) Never above 374 volts. Never below 363 volts.
The Zilla controller won't put out full motor current at any input
voltage above 375 volts, so that is why we have chosen to configure
the pack to deliver, at most, 374 volts at the starting line. We want
maximum motor current for the launch.
Also, the cells deliver the most HP/pound at 3.4 volts per cell. This
is because, like a surface charge on lead-acid batteries, A123 cells
have higher internal resistance above 3.4 volts.
Bill Dube'
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I think we shouldn´t automatically choose the cheapest battery , but
consider the safety issues also. We can´t afford news about EV´s
exploding or getting fire because of their lithium batteries...
I´ve done some testing with Kokam and A123, which have the reputation
of being the safest lithium cells available I believe. Imagine a
worst case scenario: a hot summer day and an EV with a poorly
ventilated battery box, then a collision where the battery case is
broken and one of the cells punctured with some metal part.
So, I did a nail puncture test with fully charged cells at 60 degree
Celsius (140 F). Both Kokam 40 Ah High Power cell and A123 caught
quite an agressive fire, that lasted several minutes. That would
propably make the other cells of the pack to catch a fire also.
I´ve got several safety test papers from Kokam, but none of them
includes a nail test. I think there was a nail puncture video on the
A123 site before? I can´t find it anymore. I may be wrong. Anyway,
A123 is said to be "inherently safe". They also say: "...the active
materials ...are not combustible and do not release oxygen if exposed
to high temperature or in the event of battery failure or mechanical
abuse." I´m confused.
I repeated the test with another A123 cell, and that one didn´t catch
fire, just smoke and some liquid leaking out.
I´d like to hear if someone else has done any safety tests.
terveisin,
Osmo
Ian Hooper kirjoitti 19.4.2007 kello 8.07:
On 19/04/2007, at 11:46 AM, Ryan Stotts wrote:
high energy 2.2A 18650's 1.5ah for $6/cell, 2000cycles to 80%
I got the impression from the video that the GM/Tesla price is
$2/cell. If that's the case, then that means the batteries CAN BE
had
at that price and the manufacturer is still making a profit.
For reference, the latest price list I got from ThunderSky puts
their lithiums at US$0.50/Wh - and that's sample quantity pricing.
Once the Tesla's get on the road and are proven; I think things will
really start to change. It has a relatively small pack too doesn't
it? What if it had a pack that was double or triple that size? How
about the range then?
IIRC the Tesla pack contains 6831x 18650 cells, or about 50kWh and
400kgs. I tend to think this is a pretty big pack for an EV
(enabling the 250 mile range), and IMHO having 1/3rd of the vehicle
weight in batteries is about as much as you'd want in a production
vehicle.
That said, lithium batteries really are getting better all the time
- I notice you can get 18650 cells over 220Wh/kg now (e.g http://
www.megabatteries.com/item_details.asp?id=14348&cat_id=51). 400kg
worth of those would be approaching 100kWh! (But would cost more
than a house..)
Get the Killacycle in 7's. What could the Current Eliminator and the
new truck, and White Zombie run on A123's? Are A123's king of the
world and nothing else compares? They have no competition?
I've never come across any other cells with discharge rates as high
as the A123s, no.. Plenty of LiPos out there can do 40C though, e.g
http://www.kokam.com/product/product_pdf/rc_070226/
SLPB11043140H_4800mAh_Grade.pdf - still a whole lot of power, and
they have almost 50% higher energy density than the A123s (155Wh/kg
vs 108Wh/kg). Arguably that's more important than 100C discharge
rates! But, once again, prohibitively expensive for EV-sized packs.
-Ian
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