Auxiliary materials commonly used in the production of battery FPC circuit board

The production process of battery FPC is complicated, from cutting and drilling to packaging and shipping, there are more than 20 processes in the middle. In this long production process, according to customer demand, a variety of auxiliary materials will be used. The substrate of FPC is usually double-sided or single-sided copper foil, which is the foundation of the whole FPC, and the electrical performance of FPC is determined by it. Other auxiliary materials are only used to assist installation and adapt to the use environment. There are mainly the following kinds.
1. FR4- has a hard texture, with different thicknesses of 0.15-2.0mm, and is mainly used on the opposite side of FPC welding, as a reinforcement to facilitate stable and reliable welding;
FR-4 is a code name of a fire-resistant material grade, which means that the resin material must be able to extinguish itself after burning. It is not a material name, but a material grade. Therefore, at present, there are many kinds of FR-4 grade materials commonly used for flexible circuit boards, but most of them are composite materials made of so-called Tera-Function epoxy resin, Filler and glass fiber.
2. PI tape-the texture is soft and flexible, and it is mainly used for thickening and strengthening in the golden finger area, which is easy to plug;
PI tape, the full name of which is polyimide tape. PI tape is based on polyimide film, imported from pressure sensitive adhesives, silicone, and has high and low temperature resistance, acid and alkali resistance, solvent resistance, electrical insulation (H grade), radiation protection and other properties. It is suitable for wave soldering tin shielding of electronic circuit boards, insulation of gold fingers and high-grade electrical appliances, insulation of motors, and fixing of positive and negative lugs of lithium batteries.
3. Steel sheet-hard in texture, same in function as FR4, used for reinforcing the welded joint, more beautiful than FR4, grounding, and higher in hardness than FR4;
Steel sheet, made of imported stainless steel by heat treatment and fine grinding, has the characteristics of high precision, strong tension, good smoothness, toughness and not easy to break.
The use of FPC auxiliary materials is ultimately determined according to the customer’s use environment and functional requirements.