A battery holder is one or more compartments or chambers for holding a battery. this is either a plastic case with the shape of the housing molded as a compartment or compartments that accept a battery or batteries, or a separate plastic holder that is mounted with screws, eyelets, glue, double-sided tape, or other means. Battery holders may have a lid to retain and protect the batteries or maybe sealed to prevent damage to circuitry and components from battery leakage. spring wire or flat tabs that press against the battery terminals are the two most common methods of making the electrical connection inside a holder. External connections on battery holders are usually made by contacts with pins, surface mount feet, solder lugs, or wire leads.