Abstract: A battery charger has a recess for accommodating a battery pack, and charging electrodes projecting into the recess. The battery pack is charged when the battery pack is inserted into the recess and battery electrodes of the battery pack are brought into contact with the charging electrodes. In an improvement of the battery charger, the recess has portions of different shapes corresponding to respective shapes of a plurality of different battery packs for accommodating the different battery packs, and the charging electrodes have portions projecting into the recess portions respectively.

Abstract: A battery casing for receiving one or more batteries, such as dry cells, to supply a battery-powered electrical device comprises first and second terminals for deriving electrical power from the battery. At least one of the first and second terminals is entirely received in the bore of the casing and is arranged to be in contact with an external conductor which will be inserted through an opening made in the top portion of the casing. The battery casing comprises a slidable member which opens and closes the opening at the top portion. The slidable member can be manipulated to assume its closed position so as to isolate at least one of the first and second terminals from the outside of the casing, preventing the terminals from making a short circuit. One of the first and second terminals, which can be isolated by the slidable member, is fixedly supported by an insulating member and is substantially U-shaped, while the other terminal may be L-shaped and a portion thereof is exposed outside.