What was found
ON ARRIVAL, WITH BOTH DOORS STILL ARMED, NEITHER SLIDE ARMED INDICATION WAS SHOWING ON ECAM. BOTH WORKED 4.0 PRIOR TO DEPARTURE. FOUND NR 2 BATTERY FAILED. REMOVED AND REPLACED THE BATTERY IAW MM 24-31-11-04. BOTH SLIDE ARM INDICATIONS CHECKED OK IAW TSM 52-73-00, AND MM 52-73-00-05. ACFT OK TO CONTINUE.