I DROVE MY BMW X5 TO WORK WAS THERE FROM 1045 AM TO AROUND 730PM DROVE TO THE STORE ABOUT A MILE AWAY THEN DROVE TO THE GAS STATION PUT GAS IN, THEN DRIVE TO A NEAR BY OUTSIDE MALL. WENT IN FOR ABOUT 15 MINS CAME OUT MY WINDOWS WERE COMPLETELY "FOGGED" OPEN THE DOOR AND SMOKE CAME ROLLING OUT. OPEN ALL THE DOORS TO LOCATE THE FIRE OPEN THE BACK AND FLAMES CAME SHOOTING OUT FROM UNDER THE BACK PANEL. I OPEN IT AND TRIED TO PUT OUT THE FIRE WITH SOME NEAR BY CLOTHES. A BYSTANDER RAN INTO THE STORE TO GET A FIRE EXTINGUISHER AND PUT OUT THE FIRE. THE FIRE DEPARTMENT WAS CALLED. TOOK PICTURES AND SAID IT WAS THE BATTERY THAT STARTED ON FIRE.