As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
BATTERY OTEMP L RED CAS: SHORTLY AFTER TAKE OFF FROM TEB, BATT OTEMP L ILLUMINATED. CREW PERFORMED IMMEDIATE ACTION ITEM, RAN QRC AND QRH. BATTERY TEMP DECREASED AFTER L BATT WAS SELECTED OFF. FLIGHT RETURNED TO TEB. CORRECTIVE ACTION; REPLACED L/H NICAD BATTERY. PERFORMED BATTERY OPERATIONAL CHECK. NO DEFECTS NOTED AT THIS TIME. MONITORED BATTERY TEMPERATURES AND BOTH BATTERYS WERE WITHIN LIMITS. WORK PERFORMED IAW CE-680 AMM 24-30-05,