An electronic device for automatically discharging and charging nickel cadmium batteries. When used regularly the device will prevent `memory` from developing in nickel cadmium cells. The prevention of memory development greatly increases the batteries' useful life and provides for predictable performance. The device is simple to operate, requires no technical knowledge on the part of the user, is completely automatic requiring no monitoring while the device functions, and is relatively inexpensive. The device is intended to replace the standard battery charger while providing a most useful function in addition to charging alone.The device discharges a battery or multiple configuration of batteries (battery packs) to a very specific level and then automatically charges the batteries at a slow rate. Charge and discharge rates are low to preclude damage to the batteries. The device employes a precision voltage reference which is used to compare against the discharging batteries' voltage to sense exactly when to exit discharge and enter charge. The precision voltage reference is also utilized to compare against the charging batteries' voltage so as to indicate when the battery has reached the full charge state. An indicating means is also provided to indicate that discharge is active. The device includes a simple means for disabling the discharge mode so as to function as a charger only and includes a means for restarting the discharge mode at any time.