I've been working on an electric motorcycle for a few years now (Baja bv250 frame, Perm132 72v motor).
I bough six 55ah AGM SLA batteries probably earlier in the project than I aught to have and while I think they'll still be good for bench testing with some desulfurization I don't think they'll be worth continuing with as my final power source so I wanted to explore alternatives.
Digging around online I've been seeing that high discharge Li-Ion cells have come down a fair bit in price since I embarked on this project but while I've used Li-ion for small scale projects I've never done anything that even holds a candle to this.
My thinking was a 20s20p pack to approximate my current bulky lead acid rig in amp hours, voltage, and discharge capability but I'm not sure where it would be best to start on such an endeavor.
I just found this forum and I already see a couple of threads that might be what I'm looking for but while I start sifting through those I wanted to put the question to the community.
I guess boiled down here are the general sticking points that I can see (I'm sure there are others though):
- How best to source good cells in this quantity
- How to handle a BMS on this scale
- How best to layout the pack for extensibility (possibly adding additional parallel cells later to increase range if needed)
- Pitfalls to look out for on a pack of this size
Are there any build logs of people doing this before?
Any help would be greatly appreciated.
In the mean time I'm going to start sifting through the treasure trove of information you all have complied here.