As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CLIMB, CREW RECEIVED R/H BATTERY OVERHEAT YELLOW EICAS MESSAGE - 170 RED TEMPERATURE INDICATION. CHECK LIST FOLLOWED, EMERGENCY DECLARED, AND UNSCHEDULED LANDING PERFORMED WITHOUT INCIDENT. MAINTENANCE EVALUATION ISOLATED AS FALSE INDICATION ISSUE, BATTERY WAS NOT HOT. BATTERY WILL BE REMOVED AN REPLACED.