For battery operate product, there is a battery compartment for installing batteries
connect to the internal circuitry. The battery contact is metal in either
form of following materials.
Pre-Nickel plated spring wire
? It is Pre-nickel plated carbon steel wire cuts and forms to different shape of
? It is the lowest cost material for contact spring and easy forming process.
? There is chance of rusting at the cutting point.
? Spring may be riveted on metal plate as negative pole contact to provide pressure
Post-Nickel plated spring wire
? The pre-Nickel plated carbon steel wire or Stainless steel wire is cut and form
to different shape of contact springs.
? Then the spring is process for Post Ni-plating process to prevent it from rusting
at the cutting ends.
? It is expensive than Pre Nickel plated wire.
Metal contact plate
? It is formed from copper alloy plate, e.g., Bronze or Phosphor Bronze.
? Then it is undergoing plating process for Nickel overcoat or better as Gold
? It is expensive than wire coil spring as it requires tooling for forming different
? It gives the best contact characteristic as allowing larger current and small
material resistance. Rechargeable battery should use this kind of contact