Electrified Downhill bike

[Metallover]

You could charge a123s straigh off a power supply and the pack would stay balanced. Ebikes, especially with hub motors seeing around 20a max, and a large capacity pack capable of 100s of Amps, don't even make these cells sweat. Look around on ES and see what they say about the a123 cells.

I dont balance charge my turnigy pack, although I balance them every five runs orand; they are never off by much. I charge them in a 6s 6p configuration...

The only thing you really need is a lvc. Hobbycity has a few alarms, I love the voltage and temperature monitor. Check the balance ever couple weeks with a voltmeter and balance charge if needed, but with a123s you should be ok.

[zeropointbug]

Well traditionally I have never balanced charged my A123 packs (checked my A123 thread?), but those are small R/C packs, not much cost in them... this is a $550 battery (still cheap compared to lipos!), I am not sure if I want to risk it, you know?

Unless the tolerances are even better than M1's, then sure I might go for a PSU charge. I know I will at least put balance plugs on obviously just for checking cell voltages if I didn't use balance charger.

I asking cell_man what he thinks.

[zeropointbug]

Cost of these 15Ah A123 prismatics:
$2.50/Ah x 15Ah
= $37/cell
= $0.77/Wh

For a 48volt pack:
16s1p pack - 720Wh - 51.2V nominal/15Ah rated
$592 + shipping

Rough calculations: @40km/h (25mph) conservative calcs, hypothetically if you drove 30 miles a day, using 100% DOD.

30 miles range (w/o pedal assist)
2000+ minimum cycle life (to 80% OC) - 100% DOD
= 60,000 miles minimum life mileage
=$0.01/mile over minimum life expectancy
=+$0.002/mile of electrical power bill @ 9 cent/KWh (the rate I pay in SK, Canada)

Pretty dang cheap transportation if you ask me. At the discharge rates you see with an ebike, these batts should last alot more than 2000 cycles if the pack is built properly.

Metallover, what are the capacities your Turnigy packs now? How old are they?