A battery holder is a device having one or more compartments or chambers for holding batteries. For dry-cell, the holder must also make electrical contact with the batteries terminals and for wet cells, the cables are often connected to the battery terminals as it is found in automobiles or emergency lighting equipment.
Thus a battery holder is either a plastic case with the shape of housing molding as a compartment or compartment that accepts batteries or there can be a separate plastic holder that is mounted with the screw, eyelets, glue, double-sided tape, or by other means. Battery holders may have a lid to retain and to protect the batteries or it may be sealed to prevent damage to circuitry and components from battery leakage.
Coiled spring wire or flat tabs that press against the battery terminal are the two most common methods of making the electrical connection inside those holders. External connections on battery holders are usually made contacts with pins, surface mount feet, solder lugs, or wire leads. The battery is expected to last over the life of the product then no holder is necessary and a tab welded to the battery terminals can be directly soldered to a printed circuit board.
- The design of the battery holder requires knowledge of how and where the larger product will be used. Thus human factors to be considered include ease of batteries exchange, age-range and physical condition of the intended user. So this element needs to be considered or must take into account for a design to be successful and are part of the design process. A designer must select between battery holders molded into the product case or made as a separate part. For much product regulation and for product safety standards affect the battery holder selection. Most of the battery holders are made up of polypropylene or nylon bodies related to 80-1000C and lithium coil cell holders are made with high-temperature PBT, nylon, or LCP bodies because they normally are circuited board mounted and require wave soldering at 180-2400C.
Since batteries are nickel-plated it is recommended the contacts be nickel-plated to prevent galvanic corrosion between dissimilar metals. Batteries contacts may be fixed contact or flexible contact or some combination of these two.