Hello can any one tell me what the best battery replacement to buy for the ox-1 would be.

I am looking for longer run time with the same speed and power bursts. I am using the 25c 11.1v 3 cell
Which came with the car. Everything on the car is still all stock parts. I was wondering can I do this without
Changing the motor and the speed controller.

I will post some vids of my car soon thank you.