As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LAS - EEL - AFTER TAKEOFF OUT OF BWI THE FLIGHT ATTENDANT INFORMED THE FLIGHT DECK THAT EMERGENCY LIGHTS ILLUMINATED AND LATER WENT OUT. MAINTENANCE TROUBLESHOT AND FOUND ALL EMERGENCY LIGHT BATTERIES WEAK, REPLACED ALL EMERGENCY LIGHT BATTERY PACKS PER BMM 33-51-07, FUNCTIONAL TEST WAS GOOD IAW T/C A1C33607.