Ni-Cd batteries remember how much charge was released on previous discharges. It has a tendency to release the same amount of energy with every charge/discharge cycle. If a Ni-Cd battery is always partially discharged before recharging, the usable capacity of the battery will be reduced. The Ni-MH battery is also affected by memory effect but to a lesser degree. A periodic discharge to one volt per cell or "exercise" is essential for Ni-Cd cells to prevent the building-up of memory. "Conditioning" (fully discharging and then fully charging) a battery pack also helps minimizing memory effect. Batteries can be fully discharged by disconnecting the equipment from the AC power supply and letting the equipment run on battery power until it ceases to function. Conditioning the battery once a month will keep it performing at its optimum level for a long time.more info: www.camera-battery.org
