Batteries: state of the union?

[grwsaltspring]

Hi All;

I'm thinking of building another e-bike.

What is going on that is new and exciting in the world of batteries?

I suppose a related question would be are the controllers keeping pace, but perhaps that is a different thread.

Cheers Greg

 

[Link]

Use the search bar to look for "LiFePO". That should tell you what you need to know.

And, yes. I suppose the controllers are keeping up. 8)

 

[lazarus2405]

a123 cells are the best (found in DeWalt 33V 2.3Ah powertool packs). Super high discharge rates (30C), but they're getting expensive now that they're getting popular. Chinese LiFePO4 are plentiful and cheap but have low discharge rates. E-moli cells are pretty good (found in Milwaukee 28V 3Ah packs), about 40% cheaper than a123s (per watt-hour), but only have half the discharge rate... which is still far more than ebikes need.

Lead is still dirt cheap and heavy. Nickel is still temperamental.

As for controllers... define "keeping up". As far as I know, the only controllers that really "keep up" with a123s' insane discharge rates are the high end Kelly units, but who needs to run 500A? So unless you're running an Etek motor, yeah, the controllers are up to it. Crystalyte 72V40A controllers modified with IRFB4110 mosfets running somewhere between 66-100V and 40-100A are pretty popular and do the trick unless you want to run above 60mph.