Yes, 64 cells in series, like in "sixty four".Did you mean 64 cells? What is the voltage of one cell?
There are actually a couple I know of off the top of my head:Any commercially available chargers/balancers don't support anywhere near that amount, what solutions are commonly used for this by DIY battery builders here?
That will be only 3Ah (3 times 18650 1Ah parallel). Or maybe 4.I need to know the size of your cells to make useful advice.
They will self balance within that cell group of parallel cells. You still need to balance the pack. You might have one group at 3.1V and another at 3.3V. They all need to start at the same voltage.In parallel I don't need any balancing, they will self-balance, yes?
Yes, 64S3P. Cells are A123 (cheap B-grade) of course (why does anyone buy anything else?), and each can be charged at 5A, so three in parallel makes 15A.So you got a 64S 3P out of 18650 cells, correct?
I think (no experience) it could be a little tricky to wire them up to a balancing system and let every connection be in place for a long time ... I will follow your thread to see it
What kind of cells did you chosen? The NCR-18650A for example should be chargeed at 885mA, so three parallel would be 2,66A, not 4Amps ...
I'm doing the same thing with ~96 Syncor modules, they were under $5 each NOS from ebay. Unfortunatially the seller has now sold out of them but the model # is PQ48033QGA25NKS they turn up once in awhile as surplus.Can you provide a link or part number to the DC-DC converters you use? And how much they did cost you per piece?
Yes, 64S3P. Cells are A123 (cheap B-grade) of course (why does anyone buy anything else?), and each can be charged at 5A, so three in parallel makes 15A.
I am seriously thinking that instead of buying an expensive charger and complicated balancer, to hook up 64 different DC-DC converters - one for each group of 3 parallel cells. Like the guy here does: http://electricporsche.rwaudio.com/2010/11/electric-porsche-charger-design/
Do you think that's a good idea in my situation?
Wait, do you mean that this: http://www.tppacks.com/proddetail.asp?prod=Battery-Pack-Kit is not a good method to making an A123 pack?The MAIN reason people don't use A123, is they're expensive for a large pack with any sort of real range, and a REAL PAIN IN THE ASS to put a pack together. You cannot compress the ends, because it interferes with the pressure seal.