As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CLIMB, THE CREW RECEIVED A RED WARNING PANEL INDICATION OF A NR 2 BATTERY OVERHEAT. FLIGHT 9406 RETURNED TO THE FIELD WHERE MAINTENANCE INSPECTED AND REPLACED THE NR 2 MAIN BATTERY IN ACCORDANCE WITH DORNIER MAINTENANCE MANUAL 24-00-00. OPERATIONAL CHECKS PERFORMED AND THE AIRCRAFT WAS RELEASED FOR SERVICE.