20 A/H battery

[Nick]

Is there any problem to use 20 ,24 or more A/H batteries configuration with my 36V 500W kit? Is there any problem with the motor? Has anyone used this configuration?

[Electrobent]

I found 10 AH of NiMH to be insufficient for the 500W motor.  I put two 10AH packs in parallel and other than costing and weighing more, it works great.  But if you are running LiFePO4's you should be able to draw enough current that you would not need to parallel your packs unless you need the range.  The critical factor is how much you draw at a time.  If the 500W motor peaks at 750 and you are running 36 volts, you need to be able to deliver a little over 20 Amps. If you can draw at 2C you are ok.

[Nick]

So 2X10Ah LiPO4 connected in parallel its OK? Is it possible to connect in parallel 2 10Ah LiFePO4 Battery Packs provided by Goldenmotor? Or to order a 20Ah LiFePO4 Battery Pack? Do you know if shipping cost included in price.

[emarty]

It doesn't matter how you hook up the batteries in parallel to get the amps you want.  The controller and motor are only going to draw the amps the controller will let go thru.  Higher amp controller will draw more amps and batteries if Lithium will provide more amps than the lead acid.  Works out to more speed at the expense of less range.  With Lithium and enough amps this isn't much of a factor.  With Lead acid you get the slump and shorter range unless you you with something greater than the 10amp hour normal fare of batteries being sold.  I just increased my sla's to 12 amp hour and the extra 20 percent seems to have taken care of the slump problem.  I only commute 8 miles though.

[Nick]

If I order 2 LifePO4 (10Ah) bateries and when one discharges use the second one to get more range do you think it's a good configuration? What the range that I can get from a single LifePO4 (10Ah) battery? I need a range of about 25 miles with least pedaling...

[biohazardman]

Nick my bike and I weigh near 260lbs and I get near 20 miles out of a single LifePo4 36v pack, with the same motor as you, pedaling only to help accelerate from a stop and keep up speed on any hills there are.  Yes two of the GM 36V packs will get you 25 miles with luck a bit over 35 miles.  Good rolling tires at higher pressures can help you out with a bit better mileage too. Hook the batts up in parallel to get the mileage you are after.