# e-greenmotion KHY-9059156 Batteries



## major (Apr 4, 2008)

$1/Wh seems on the high side. Or was this just a sneaky ad?


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## dougingraham (Jul 26, 2011)

To be competitive with prismatics those cells would need to be between $6 and $7 each, not $19.50 each.


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## ninjanick (Oct 11, 2014)

I want to run close to 300V, however I can only fit 60-65 CALB CA sized batteries in my chassis. I can make a much more compact traction pack with pouch cells that will still give me 1000A pulsed and nominal 500A discharge. I know there are challenges with pouch cells, but I'm willing to spend the time to design a chassis for the batteries if it will have a smaller footprint and still get me the performance I need. I'm very leery about purchasing items online overseas. I have no idea of the quality other than an e-mail from a representative stating these are brand new cells from the manufacturer.

I've been looking for more compact solutions, but haven't really come up with much other than pouch cells and a custom enclosure. Anyone got any ideas?


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## PhantomPholly (Aug 20, 2008)

If size is the only issue, then based on dimensions it looks like you could get almost twice as many of these in the same space as the CA cells. You'd get your 300 volts with 94 cells, and about 21Kwh. Have no idea if the price is "good" compared to others but it appears a bit pricier than the CA cells (a few bucks more than the 100Ah CA cells for a 72Ah cell). But, it might be worth the extra if it saves you headaches.


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## dougingraham (Jul 26, 2011)

ninjanick said:


> I want to run close to 300V, however I can only fit 60-65 CALB CA sized batteries in my chassis. I can make a much more compact traction pack with pouch cells that will still give me 1000A pulsed and nominal 500A discharge. I know there are challenges with pouch cells, but I'm willing to spend the time to design a chassis for the batteries if it will have a smaller footprint and still get me the performance I need. I'm very leery about purchasing items online overseas. I have no idea of the quality other than an e-mail from a representative stating these are brand new cells from the manufacturer.
> 
> I've been looking for more compact solutions, but haven't really come up with much other than pouch cells and a custom enclosure. Anyone got any ideas?


At the moment your requirements are a voltage close to 300 volts and you need 1000 amps briefly and 500 amps continuous. Do you have a range requirement as well? This is a horsepower peak of ~300kw (402 hp) into the motor and a continuous of ~150kw (201 hp) which seems higher than necessary unless you are doing some kind of racing. Consider that with a small sports car you can do 65 to 70 mph on the highway with only 20 kw.

With a little more information we can probably suggest a solution.


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## ninjanick (Oct 11, 2014)

My goal is an FFR 818 similar to 33 Machines/Erik Hansen. Goals are 40-60mile range with enough power to fall within the 4 - 6s range. Total vehicle weight should be around 2300lbs. with driver and passenger. My current plan:

WARP11HV
Soliton1
Subie 5MT Transmission

EVWest is working on a 3 motor design, but I'm not sure on cost or specifications.


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## dougingraham (Jul 26, 2011)

ninjanick said:


> My goal is an FFR 818 similar to 33 Machines/Erik Hansen. Goals are 40-60mile range with enough power to fall within the 4 - 6s range. Total vehicle weight should be around 2300lbs. with driver and passenger. My current plan:
> 
> WARP11HV
> Soliton1
> ...


Sounds like a fun project! For a 60 mile drop dead range and 2300 lbs you need a pack of about 13.8kwh. I would consider that to be as small as you can go. At the Soliton limit of 340 volts your max cell count at full charge of 3.4 volts is 100 cells. Tess has suggested that 94 is probably a better upper limit. A 94 cell pack will have a nominal voltage of 300.8 volts. This means you only need 46 AH cell equivalents. But to reach 1000 amps you need a cell that can do 22 C for 10 seconds or so. I think some of the Headway cells can do 25C for 10 seconds. The A123 pouch cells could do that but the granularity is not good enough with those. If you go with the requirement of 15C then there are a lot more options but the pack size needs to go up to 67 AH and then at 300.8 volts the pack has 20.2 kwh and an increase of range to 87 miles minus a little because of the extra weight of the larger pack.

I looked at pictures of the EVWest 818 project and it seemed to have plenty of room to hide the batteries. If I were doing this I would use 94 of the 60 AH Calb CA cells and set the motor current to 1000 and the battery current to 720 amps in the Soliton. This will give you 1000 amps up to a motor voltage of around 216 and at full motor voltage up to 720 amps. This battery will have 18kwh and should be capable of producing a peak of 217kw (291 hp) into the motor. I would guess a WHP of around 75% of this or 218 hp. I would expect a range of around 78 miles drop dead or 62 miles to 80% DOD. Use of more exotic batteries will get you a smaller and lighter pack but the price will be considerably higher.

Please post updates. I look forward to watching your build.


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## ninjanick (Oct 11, 2014)

I looked at the CALB CA 60aH cells and those would fit in the planned battery locations. I've seen anywhere between 8C and 12C (max discharge for 10s) ratings for this battery. Do you know of any source that has actual discharge rates?

I'll be sure to post a link to my build thread when I start it over on FFR's forum.


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## dougingraham (Jul 26, 2011)

ninjanick said:


> I looked at the CALB CA 60aH cells and those would fit in the planned battery locations. I've seen anywhere between 8C and 12C (max discharge for 10s) ratings for this battery. Do you know of any source that has actual discharge rates?


What I remember is that Jack Rickard did some testing of the CALB CA 40 series cells when they first became available and was able to do a 12C discharge for 30 seconds with only a 17% sag.

Here is a link to the Blog entry where he talks about the CA 40 testing he did.

battery-joy-and-the-car-guy/

There is a link to the video. I suggest you find this one on youtube because you can skip ahead in the youtube viewer.

Does this test apply to the CA60 cells? It probably does mostly. There is a good chance that the internals of the cells are the same only the 40 is 2/3 of the size. For 15 to 30 seconds the surface area of the cells isn't going to make any difference. Over the long term the smaller cell will be able to shed excess heat better because it has more surface area relative to the active material inside. But this isn't going to matter when you tie a bunch of them together in a large brick. The outside ones will be cooler and the inside ones will be hotter.


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## ninjanick (Oct 11, 2014)

Knowing me, I don't leave well enough alone for too long. If I went with 94 CALB CA 60aH batteries, my next logical upgrade path would be another 94 CALB CA 60aH cells in parallel to the original pack or try to fit higher capacity CALB CA cells in the space I have available. I've read a little bit regarding the Headway cells and it seems like I could build packs as time, money and range are available/needed and still come up with a decent pack that is lighter with less volume albeit more expensive. But this way it's upgradeable and can prolong the initial high cost. Perhaps a 94S2P first, then add another in parallel to achieve original goal?


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## ninjanick (Oct 11, 2014)

Sorry to pick this old thread back up, I tired to fit 94-96 CALB CA 100aH cells, but couldn't without putting 135lbs of batteries in front of the front axles which I don't like. Battery locations and boxes close if I go with the CA 60aH cells, but it also closes with the CALB CAM cells. I haven't read much on these cells other than to insulate each cell from each other and to chassis.


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## rtz (Jul 3, 2013)

Maybe even some CAM 40's for smaller/cheaper cells?

Or some 12volt style batteries?









http://www.evlithium.com/Winston_Battery.html

Or check out the interesting Nissan Leaf cells at 7.6v each:

http://www.hybridautocenter.com/HAC...leaf-battery-module-model-2012-new&Itemid=605 

I wish CALB and other brands would up the cell voltage. That Nissan trick was clever.


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## rtz (Jul 3, 2013)

Hmm.... Appears inside that "12 volt" battery is only 4 regular batteries!!


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## Hollie Maea (Dec 9, 2009)

rtz said:


> I wish CALB and other brands would up the cell voltage. That Nissan trick was clever.


It's just two cells in series. Not much of a trick.

Single cell voltage is a set function of chemistry.


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## rtz (Jul 3, 2013)

It's still nice having the higher voltage cell package for space reasons.


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## Hollie Maea (Dec 9, 2009)

rtz said:


> It's still nice having the higher voltage cell package for space reasons.


I guess. If they were lower voltage they would be half the size though. IIRC, the Nissan modules are actually 4 cells, in 2s2p configuration.


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