What kind of a motor will i need?
What kind of battery will i need? Copy existing store-bought or Internet designs.
How do i connect them? In series through a speed control device.
How do i control the acceleration?
Accel. depends on the motor's torque/speed curve, how much you weigh and what kind of hill you're climbing.
More battery amp-hours equals more operating time. The battery will last a lot longer on level ground.