Abstract: A charging system for rechargeable batteries, e.g. of the 9 volt type, includes a charger and an adapter module for mechanically and electrically interconnecting the charger to a 9 volt size battery. The adapter includes a projection or key extending upwardly from and adjacent the battery terminals to block connection of all batteries except those batteries with key receivers. In this manner, only rechargeable batteries with such receivers may be charged thereon. Finger grips on the adapter are designed to generate a moment for detachment from the charger.

Abstract: A rechargeable plug-in battery compatible with printed circuits and the like. At least one rechargeable storage cell is mounted inside a battery case having at least two terminal pins which extend through the battery case for insertion to a mating socket. Inside the casing, the pins are welded directly to the battery terminals, and recesses formed in the base and cover portions of the battery case at the interior receive the storage cell, or cells, so as to restrain them against movement.

Abstract: A charging system for rechargeable batteries of the 9 volt type includes a charger adapted to accept a plurality of cells of different sizes and electrical characteristics and an adapter module for mechanically and electrically interconnecting the charger to a 9 volt size battery.