As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
APPROXIMATELY 1 HOUR INTO FLIGHT, BATTERY CHARGER MESSAGE CAME UP ALONG WITH A BURNING ODOR. CREW DECLARED EMERGENCY AND RETURNED TO MIA. MAINTENANCE INSPECTED AIRCRAFT, REPLACED BATTERY CHARGER AND BATTERY. ALSO ACCOMPLISHED OVERWEIGHT LANDING INSPECTION. CREW REPORTED LANDING SOFT.