As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PGUA - IN FLIGHT MAIN BATTERY VOLTS DROPPED 20 VOLTS, HAD ELECTRICAL SMELL AND ADVISED FE TABLE, TURNED OFF BATTERY AND PULLED C/B FOR BATTERY CHARGER. FOUND 1 BATTERY CELL LEAKING. SWAPPED MAIN BATTERY WITH APU BATTERY, MAIN BATTERY REMOVED. (M)