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Discussion Starter #1
Hi.

I have been reading this forum for quite some time and have finally got round to starting a conversion. I'm hoping to start a build thread but for now I have a couple of questions on batteries.

I can get hold of some Boston Power Swing 4400 lithium cells (http://liionbms.com/pdf/bostonpower/swing4400.pdf) at what seems like a decent price. They are not brand new so I'm a bit wary but I haven't got a huge budget so my lithium options are limited. They apparently came out of a prototype electric van when the company developing them went bust.

Does anyone have any experience or advice on this cells? There seems to be nobody using them and I don't know if there is a good reason for that!

Is there anything that I can do if I go and have a look at them to test what kind of state they are in or whether there are any bad cells?

Thanks,

Tom
 

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"Lithium" covers a wide range of battery types.

What specific chemistry are those, and what others may you be considering?

Edit: wow, tiny capacity! Are they a small cylinder form factor like 18650 where you have to weld them together to make a large bank?
 

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Discussion Starter #4
Leaf batteries are an option. I had been looking into them before I came across these batteries. The specs seemed ok and the price is a lot cheaper than I can get a leaf pack for.

Yes, they seem to be two 18650 cells in a single oval shaped cell. The ones I am looking at have already been welded together into packs of 8 cells in parallel. I would be looking to put two of these packs in parallel to get 16 cells in parallel (3.7V 70aH). Then put 80 of these in series to get 296V.
 

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Discussion Starter #7
Very interesting, thanks. Seems like they may be worth a try as long as they haven?t been abused in their previous life.
 

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Hi Tom
LiCo is a very good chemistry for a small battery with high power and fast charging and keeping a good life. These should be great for your build if you have a good way to assemble them.
Do you have any pictures?
 

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Discussion Starter #9
I did end up purchasing these batteries. They came assembled in packs of 48 cells (6s8p) in a really nice case as they had been used previously in a prototype electric van. Unfortunately I don't have any photos, I will try to get one soon.

I'm planning to make a slight modification by connecting them in a 3s16p configuration to give me the voltage and amp hours I need. I have 28 of these packs (1344 cells in total). I might not be able to squeeze them all in but I'll use as many as I can.
 
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