Maintenance Airframe; Maintenance Powerplant
Distraction; Situational Awareness; Time Pressure
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Maintenance; Deviation / Discrepancy - Procedural Published Material / Policy
General Maintenance Action
Human Factors
I was tasked with [working several] aircraft with autothrottle inop; hgs (Heads-Up Guidance System) display inop; L2 window heat inop and engine control light write up along with the other regular task cards.  While working on [aircraft X] I accomplished step 1 (battery replacement) and since there was no part sent for the second step; I then went to work on [aircraft Y] with window heat and engine control light issues.  Meanwhile got notified that the part for the second step on [aircraft X] (battery charger) had showed up.  Went back to the first plane to complete step 2 for battery charger change.  During removal missed pulling one of the two circuit breakers both labeled battery charger. The charger cable terminal lug contacted and shorted damaging the contact terminal. Notified lead and supervisor of the issue immediately.  Engineering desk was consulted and came to consensus to re-terminate a new contact lug or replace the run for that charger cable. There was a lot of work scheduled for the night.  Parts were not all present at beginning of the shift.  While working between the AOG (Aircraft on Ground) write ups for aircraft [X and Y] I missed pulling one of the breakers labeled battery charger.
A Maintenance Technician neglected to fully remove power from the battery charger; resulting in shorting of the contact terminal that required replacement.