Al, not as complicated as you might think, Amp hour is Amp hour - same as any batteries, even cells were getting 4500 a pack a few years ago, lipos have plenty of power, shown in the 'C' rate, a 30C lipo will output more than a 20C, as a rule of thumb. 5000Ah x 30C will give you 150amps, 5000Ah x 20C will give you 100amps, you may get a burst higher than this - say 30C cont 40C burst.
The other 'C' figure is for charging, BRCA rules is 1C, so charge a 5000Ah at 5amps a 4200 at 4.2 max, we believe overcharging will not help and can cause major problems. Other numbers are the battery layout, 2S is 2 cells at 3.7volts giving 7.4volts etc.
Things you must remember, dont let the pack voltage drop below about 6volts the packs cannot be recovered, so always disconnect the battery and do not run untill flat. You can use one pack all day, charge - run (5 mins)- charge etc the packs seem quite happy. Some of the larger packs can be tight to get into the battery tray on some 10th cars, there is a BRCA approved list of batteries for BRCA events. Some Esc's have a lipo cut off to stop the car if the voltage drops to far.
You must use a Lipo charger, the old Nicad & NiMh charge profiles will cook Lipo batteries leading to swelling/bursting/fire & the end of the world as we know it.
Sure I have missed something or more likely got something wrong, but we love our Lipos - no more discharging/balancing/charging and needing half a dozen packs for a days racing.
Now - do you have question on brushless motors?
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