As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
RED WIRE CONNECTING BATTERIES WAS NOT SOLDERED PROPERLY ON 3 SETS OF BATTERIES THAT WERE RECEIVED. MOUNDS OF SOLDER APPEAR TO HAVE BEEN PLACED ON THE TERMINAL CONNECTION OF THE BATTERIES AND THE WIRES INSERTED RESULTING IN COLD SOLDER CONNECTIONS. WIRES PULLED OUT OF SOLDER CLEAN.