If you have a 2 gallon gas tank or a 5 gallon your cars engine will still make 300hp. The thing is that the one with the larger tank till run 2.5 times longer with the same load. Amp hour rating is the same, more amp hours will deliver the energy for a longer time if the load is the same.
Now the manufacture may allow the control to deliver more amps to the motor for an increased torque.