WHEN DRIVING 20 MPH AND UPON DEPRESSING BRAKE PEDAL TO MAKE A NORMAL STOP VEHICLE CONTINUED TO ACCELERATE WHICH CAUSED A REAR END COLLISION. VEHICLE CAUGHT ON FIRE DUE TO BATTERY LEAKING. ALSO, PASSENGER'S SIDE SEAT BELT DID NOT LOCK WHICH FORCED THE PASSENGER INTO THE WINDSHIELD. VEHICLE WAS A TOTAL LOSS. PLEASE PROVIDE ANY FURTHER DETAILS.*AK