Our teams and a few other teams in our region have noticed the batteries in the controllers have to be switched out very often in the competition. We figured out a way to connect the VEX legal robot batteries http://www.vexrobotics.com/vex/products/accessories/power/276-1491.html into the controller and this provided enough power to last entire competitions. At competitions the referees said we could do this but were not sure if this would be legal at worlds. Would it be legal to use a robot battery in the control? Thanks!