What was found
CABIN EMERG LIGHT: WAITED ON TAXI WAY FOR APPROXIMATELY AN HOUR WITH THE ENGINES RUNNING WAITING RO DEICE. WENT IN THE CABIN AFTER DEICE TO INSPECT THE WINGS AND NOTICED THE INTERIOR EMERGENCY LIGHTS FLICKERING ON/OFF RAPIDLY. RECYCLED THE SWITCH IN THE CABIN AND THE LIGHTS REMAINED ILLUMINATED IN THE ARM POSITION. SEVERAL MINUTES LATER STARTED FLICKERING ON/OFF AGAIN.//CORRECTIVE ACTION// REMOVED BOTH FWD AND AFT EMERGENCY BATTS AND INSTALLED 2 TESTED BATTERIES IAW EMB-505 AMM 33-52-01 ALL OPS CHECK GOOD. PN OFF:6450LS-00 SN OFF: 001671 PN ON:6450LS-00