Assembly Process of Soft-Packed Lithium Iron Phosphate Battery
March 4, 2021
Assembly process and method of soft-packed lithium iron phosphate battery
Aluminum plastic film forming process
Soft-packed lithium iron phosphate batteries can be designed into different sizes according to customer needs. When the external dimensions are designed, the corresponding mold must be opened to form the aluminum-plastic film. Generally, when the battery core is thin, choose to punch a single pit, when the battery core is thick, choose to punch a double pit, because too much deformation on one side will break through the deformation limit of the aluminum-plastic film and cause rupture.
Top side sealing process
The top-side sealing process is the first packaging process of the soft-packed lithium iron phosphate battery. The top side seal actually includes two processes, the top seal and the side seal. First put the wound core into the punched pit, and then fold the packaging film in half along the dotted line. The top seal is to seal the tab, which is made of metal. After formation, some cells, especially thick cells, may undergo certain deformation due to large internal stress. Therefore, some factories will set up a fixture shaping process after the formation, which is also called fixture baking (baking).
In the process of standing, forming, and jig shaping, after the liquid injection and one seal are completed, the battery cell should be left standing first. According to the different processes, it will be divided into high temperature standing and normal temperature standing. The purpose of standing is to make the injection Electrolyte fully soaks the pole piece. Then the batteries can be used to make them.
After the capacity is divided, the cells with qualified capacity will enter the subsequent processes, including appearance inspection, yellow glue, edge voltage detection, tab transfer welding, etc. Several processes can be added or subtracted according to customer needs. The last is OQC inspection, and then packaged and shipped.