What material should be chosen for the battery spring?

What is a battery spring? I believe everyone will think of the remote control. In fact, the battery springs are divided into three types: positive battery springs, negative battery springs, and positive and negative battery springs. Each remote control is different, so there is no fixed type of spring, and it depends on the user. The drawings given are customized. Generally, the battery spring is made of nickel-plated carbon wire. Why? Due to the strong electrical conductivity of nickel-plated carbon wire, there are individual users who choose copper, iron, or stainless steel to do it. The following will introduce how to choose battery spring materials.