The process of producing battery FPC is complicated. From cutting and drilling to packaging and shipping, there are more than 20 processes required in the middle. In this long production process, according to customer needs, a variety of auxiliary materials will be used. The base material of FPC is generally double-sided or single-sided copper foil, which is the basis of the entire FPC, and the electrical performance of the FPC is determined by it. Other auxiliary materials are only used to assist in installation and adapt to the use environment. There are mainly the following.

1. FR4- is hard in texture and has different thicknesses of 0.15-2.0mm. It is mainly used on the opposite side of the FPC welding place, as a reinforcement, convenient for welding, stable and reliable;

FR-4 is the code name of a flame-resistant material grade. It represents a material specification that the resin material must be able to extinguish by itself after burning. It is not a material name, but a material grade. Therefore, the current general circuit There are many types of FR-4 grade materials used in board soft boards, but most of them are composites made of so-called Tera-Function epoxy resin, Filler, and glass fiber. Material.

2. PI tape-soft texture and bendable, it is mainly used for thickening and strengthening the golden finger area, which is convenient for plugging and unplugging;

PI tape, its full name is polyimide tape. PI tape is based on polyimide film and imported organic silicon pressure-sensitive adhesive. It has the properties of high and low temperature resistance, acid and alkali resistance, solvent resistance, electrical insulation (level H), and radiation protection. It is suitable for shielding of wave soldering tin on electronic circuit boards, protecting gold fingers, high-end electrical insulation, motor insulation, and fixing the positive and negative poles of lithium batteries.

3. Steel sheet-hard texture, the same function as FR4, used to strengthen the welding place, more beautiful than FR4, groundable, higher hardness than FR4;

The steel sheet is made of imported stainless steel after heat treatment and fine grinding. It has the characteristics of high precision, strong pulling force, good smoothness, toughness and not easy to break.

The use of FPC auxiliary materials will ultimately be determined according to the customer's use environment and functional requirements.