Methods and apparatus of the invention include one or more of the following: (a) a battery having an electrode that develops a resistive film from inadequate discharge events, (b) a non- or slowly-deforming capacitor capable of storing a charge from the battery, the capacitor requiring no or few periodic battery discharges for reforming oxide, (c) means for periodically discharging the battery to reduce the film on the electrode, (d) a lead for sensing physiologic electrical signals of a patient, (e) a status system for monitoring cardiac activity of the patient, (f) a therapy delivery system for delivering therapeutic electrical energy to the patient, (g) a means for determining elapsed time since a therapy delivery event occurred and/or battery discharge adequate to remove film, (h) a means for optimizing battery discharge, and (i) a means for optimizing the time between discharging the battery.