NOVELTY - The system has a battery (15) electrically connected to a control circuit (10). A movable motor includes an actuator directly/indirectly electrically connected to the control circuit and a coil member secures to the actuator and is electrically connected to the control circuit. A magnetic member of the motor is adapted for effectively rotating relative to the coil member. The actuator is controlled by the control circuit to move so as to actuate the coil member to approach to or depart from the magnetic member, so that the coil member and the magnetic member are controlled to sense.    USE - Vehicle-used composite braking/accelerating system for use in a vehicle i.e. car, for recycling kinetic energy.    ADVANTAGE - The system facilitates the acceleration of the vehicle. The movable motor is adapted for recycling the kinetic energy of the moving vehicle when the vehicle is braked to decelerate, so that the recycled kinetic energy is transformed into electrical energy and saved into a battery, thus the system allows the battery to output the electrical energy for driving the vehicle to move when the battery contains sufficient electrical energy, and hence saving the fuel consumption. The engine of the vehicle operates to drive the vehicle and charges the battery when the electrical energy saved in the battery is insufficient. The actuator disengages the movable motor from the tire system when the vehicle is solely driven by the engine, so as to completely exert the capacity of the engine and eliminate the restraint of the movable motor. The control circuit is adapted for monitoring the rotation speed of each tire for adjusting the output of each motor so as to avoid the tire slippage. The system includes an information display unit placed at an instrument panel positioned in front of the driver seat so as to allow the driver to clearly view related data including motor rotation speeds, moving status, electrical energy volume of the battery, and electrical energy consumption information. The control circuit is adapted for monitoring instant moving speed of the vehicle and allowed to adjust an output ratio between the engine and the movable motor, thus saving fuel consumption, and hence reducing the greenhouse effect.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic block diagram of a vehicle-used composite braking/accelerating system.    Control circuit (10)    Electric appliances (12)    Ignition system (13)    Generator (14)    Battery (15)