# A123 Unobtainium?



## Brute Force (Aug 28, 2010)

Thanks to Headway's (poor) decision to obsolete the 40160, I'm back to looking for cells. My first choice has always been a set of A123 AHR32157M1HD. Problem is, I have not been able to find a reputable distributor which is why I settled in on the Headways. Anyone have have a suggestion on who I might be able to contact about making a purchase?


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## steven4601 (Nov 11, 2010)

HI,
I really like the twin motor vehicle you made.

About A123, sorry cant help you. But I am also interested in the same answers. 

All news lately is about the A123 20Ah pouches, where to source them or not etc. Mr Rickard from EVTV video blog has been receiving phone calls from suppliers selling the cells for good prices in higher quantities. (at or almost at 1 dollar per amp-hour)

It appears most internet sources of these cells sell castrated cells, where the tabs have been cut off to a point it becomes a liability to try to use them. 
I also bought 100 26650 anr cells from a internet supplier which name sounds remarkably like 123, but sadly enough, sold as new, but those cells where repackaged rejects. (the brandname had been erased with a laser)



About your vehicle, are prismatics an option? Or is weight a restriction ?


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## MN Driver (Sep 29, 2009)

Wasn't the 16Ah 42160 a superior cell to the 40160 anyway? I thought it had better charge/discharge capability, probably the only disadvantage was probably just the extra 2mm of diameter. I almost bought 60 of them but then was discouraged by various forum posts about Headway cells not taking charging above 1/2C very well so I scrapped the idea because my application required higher charging amperage.


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## Brute Force (Aug 28, 2010)

Never heard of a 42160, so I couldn't comment about their superiority.

I've only briefly looked at prismatics. Only the small (40Ah) size are short enough to fit in the available space. And the way they have to be packed does not dissipate heat well.

I've contacted Mavizen to see what they can do for me. They claim to be an A123 dealer and appear to be selling A123 pouch cells, but don't mention anything about cylindricals.


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## Yabert (Feb 7, 2010)

Brute Force said:


> I've only briefly looked at prismatics. Only the small (40Ah) size are short enough to fit in the available space. And the way they have to be packed does not dissipate heat well.


Not well, but probably better than your last lead pack! No?

Why don't share with us about your battery emplacement space? We can maybe help you. Picture? Dimension?


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## Brute Force (Aug 28, 2010)

I'm hoping to learn from my mistakes, not build on them. 

I have three battery packs, each one is 71.5" long (181 cm) by 7" wide (18 cm) by 8" tall (20 cm). Currently they each house seven Optima Yellow Tops. The framework of the vehicle surrounds these three packs with little room to spare, so changing the dimensions of the packs would require a major rebuild of the chassis.
















I had a preliminary design with 210 of the Headway 40160 in each box. I've a new preliminary design with 300 of the A123 32157 that lays out nicer. But it's moot if I can't buy them anywhere.


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## Yabert (Feb 7, 2010)

Nice! Thanks to share. 

I have a better understanding of your challenge. Put many prismatic cells in this tiny tunnel will be crazy when will come the time to connect each cell terminal together.

So, a 80S 2P (256v 80Ah) of Calb 40Ah can maybe fit. 8200$ only, 500 lbs, 20 Kwh of energy storage, but I doubt than her peak power and continous power will be enough for you. I talk about 179 Kw peak and 77 Kw continous. (from spec sheet).

If you need to stay with Lifepo4 cell, you can maybe put an eye on Headway 38120 HP.
A 78S 10P (250v 80Ah) can fit in your tunnels, but 78S 8P can be enough and less trouble (624 cells!!). Probably 13-15K$, 453 lbs, 16 Kwh of energy storage, around 325 Kw peak and 145 Kw continous (less than 5 mins of ride).

But I'm interested to know what is your main goal.... If we compare to your Optima battery pack.
More than 900 lbs, less than 200 peak HP at motor shaft and probably under 7 Kwh of usable energy.
From that, what do you need to increase. Peak power only? Reduce weight?Range?


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## novatin (Mar 30, 2010)

I bougth somo of those and all of them came in good condition (And with full tabs)

http://www.a123rc.com/goods-468-Excitingly+Powerful+A+123+20ah+PRISMATIC+CELLS.html

Regards.


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## rwaudio (May 22, 2008)

What about the A123 20ah pouches laying flat... IE instead of the cells standing up (you don't have enough height) have them lay flat either in single stacks or double sided stacks with cells layed end to end electrically connected as you build the stack upwards to the desired height.

Although not easy to connect I think it would be easier than using the smaller A123 cells.


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## madmike8 (Jun 16, 2011)

The Sinopoly SP-LFP60AHA are only 183mm Tall... Not sure if that helps...


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## DIYguy (Sep 18, 2008)

Brute Force said:


> Thanks to Headway's (poor) decision to obsolete the 40160, I'm back to looking for cells. My first choice has always been a set of A123 AHR32157M1HD. Problem is, I have not been able to find a reputable distributor which is why I settled in on the Headways. Anyone have have a suggestion on who I might be able to contact about making a purchase?


Ah yes, the 32157. . . tell me, why do you like this cell so much? What do you know about it?


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## frodus (Apr 12, 2008)

If you do source them, have fun welding them, they're not screw ends, they've got a divot in the end that looks like it's a threaded end, but it's not. They're meant to be welded. Expect to either spend a lot of money, or build your own CD Battery Tab Welder (note, this is not like a normal metal welder).


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## DIYguy (Sep 18, 2008)

Ever tested any? Some have screw studs.....


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## frodus (Apr 12, 2008)

I've seen the screw terminals only a couple times, most are via the chinese reseller places, and I wouldn't trust them for anything. 

If he can source them with studs, great.

I've held one of the 32157's, it was the type you weld. I haven't seen any of these on the open market and I seriously doubt A123 is going to sell direct to anyone (lots of history of people being ignored by A123). The one I saw was a sample for an OEM.


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## Brute Force (Aug 28, 2010)

My main goal with the new battery pack is to maximize range. Picking the right cells gets me increased maximum power. And losing weight come along as a natural consequence of the lithium based chemistry. It's win-win-win all the way around. My initial design with the Headway 40160 quadrupled the kWh of the Optimas, doubled the max current, and was 300lbs lighter.

I've only been able to glean bits and pieces of information about the A123 32157 from old post on various forums, and a spiffy NASA powerpoint presentation I blundered across. But I'm beginning to see that it was just a mirage. Physically, they're 32mm in diameter and 157mm long, which fills out my battery boxes nearly ideally. Pictures I came across showed them with threaded ends or studs, perfect for a DIY build. And they had three variants, the -HD 10Ah, the -A 8Ah, and the -B 7 Ah. But A123 has removed all references from their web site. And Mavizen, the only legitimate A123 dealer I've been able to locate, has not heard of the 32157. So short of rolling the dice on counterfeits of unknown quality directly from China, it's looking like the 32157 is a dead end.

But I am taking a serious look at what I could do with the AMP20, which is available from Mavizen.


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## frodus (Apr 12, 2008)

I don't have any direct experience with Mavizen, but they seem to be the only licensed legit game around for the A123 20Ah cells.

You don't have to weld those. There's some examples of people putting tabbed cells together. It's not the simplest solution, but it's nice because you can replace them if you have a bad cell.


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## drgrieve (Apr 14, 2011)

What about something easier. Calb 40ah cells.

They should slot together better than spec sheet, someone who has them will be able to you the final dimensions.

But I think you could fit 

http://www.calibpower.com/ProductDetails.aspx?p=2&id=1

15*4 in 3 boxes = 180*40ah = 23 kWh


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## JRP3 (Mar 7, 2008)

novatin said:


> I bougth somo of those and all of them came in good condition (And with full tabs)
> 
> http://www.a123rc.com/goods-468-Excitingly+Powerful+A+123+20ah+PRISMATIC+CELLS.html
> 
> Regards.


Price is about twice what you can get them for now.


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## Yabert (Feb 7, 2010)

Brute Force said:


> My main goal with the new battery pack is to maximize range.


Well, I understand clearly now why a 32 Kwh battery pack build with 40160S would have been perfect... No really high power, but a good continous power for long range!

So, the ultra powerfull 38120 HP (less than 3 mohm per cell) isn't right for your challenge (too much power and not enough range). And it's too bad than you are limited by your availiable free space.

Anyway, you can try to fit 780 cell 38120S for 25Kwh (78S 10P). But isn't fun to play with 3000 parts to build a battery pack!


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## novatin (Mar 30, 2010)

JRP3 said:


> Price is about twice what you can get them for now.


Yes, but with the free shiping it´s the same than from ONSPower (in a 12 units buy);http://www.osnpower.com/productID/product_detail-10726328.html

Also Victpower sells them;
http://endless-sphere.com/forums/viewtopic.php?f=14&t=33939



Any other cheap source????


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