Battery Choices

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From RollingResistance we know that power required at 95km/h is approximately 11kW. We assume 85% efficiency, and calculate current at 240V, 288V and 324V. We choose 240V because it's a nice round number. 288V is important as any more would require more than 3 relay boards for the Battery Balancer. The desired range is about 50km at 95km/h, which discharges the batteries in 32 minutes.

Voltage Current Ah at 30minute rate
240 54 27
288 45 22
324 40 20

Lithium

I've bought 120 40Ah Thunder Sky LiFePO4 cells. I hope they turn out to be a good investment as Thunder Sky don't have the best reputation.

Thunder Sky are talking about opening a factory in the USA http://www.nabble.com/International-Battery-Inc-t4952860s25542.html. My cells are coming from China.