As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
BATTERY WAS MAKING NOISE BUBBLING AND CRACKING. WHEN ON CHARGE, BATTERY CAME UP TO 29 VOLTS. REMOVED BATTERY FOR TEST, OPEN CIRCUIT VOLTS 25.7. PUT LOAD ON BATTERY, 200 AMPS. WHEN SWITCH WAS TURNED ON, BATTERY BLEW HOLE IN THE SIDE. TEST WAS DONE IN AERO BATTERY SHOP. SUPPORT SLEEVE WAS UP AT THE TIME. CYCLES: 242.