An apparatus capable of charging a battery mounted on a robot while allowing the robot to remain stably still in the state of standing on its legs is provided. Driving a first connector backward while it is connected with a second connector would cause a body of the robot to tilt as if being pulled by the first connector. However, it is possible to prevent the posture of the robot from becoming unstable by utilizing the fact that the connected state of first signal terminals and second signal terminals is maintained in that state. The backward driving of the first connector is restricted when a charge control unit is capable of communicating with a control system via the first signal terminals and the second signal terminals. This prevents the undesirable event that the posture of the robot becomes unstable due to the first connector being driven backward unconditionally.