Aluminum-plastic film forming process
Soft coated lithium iron phosphate cell can be designed according to the needs of customers into different sizes, when the overall size design is good, it is necessary to open the corresponding mold, so that the aluminum plastic film molding. Generally, when the cell is thin, choose to punch a single pit, and when the cell is thick, choose to punch a double pit, because the deformation of one side is too large to break the deformation limit of the aluminum-plastic film, resulting in rupture.
Top side sealing process
The top side sealing process is the first packaging process of soft coated lithium iron phosphate battery. Top side sealing actually includes two processes, top sealing and side sealing. First of all, put the coiled core into the punched pit, and then fold the packaging film in half along the dotted line position, the top seal is to seal the pole ear, the pole ear is metal. After the formation of some cells, especially thick cells, due to large internal stress, there may be a certain deformation. Therefore, some factories will set up a fixture shaping process after formation, also known as fixture baking (baking).
After the two seals cut the air bag, they should be cut and folded, which is to cut the edge and the two seals to the appropriate width, and then fold it up to ensure that the width of the cell is not exceeded. The battery cell after the hem can be divided into the capacity cabinet, which is actually a capacity test to see whether the capacity of the battery cell has reached the specified minimum value. In principle, all cells must be tested before leaving the factory to ensure that cells with unqualified capacity will not be sent to customers. However, when the cell production is large, some companies will do part of the capacity to determine the pass rate of the batch of cell capacity with statistical probability.
Static, formation, fixture shaping process, after the completion of liquid injection and a letter, the battery must first be static, according to the different process will be divided into high temperature static and normal temperature static, static purpose is to let the injected electrolyte fully infiltrate the pole sheet. Then the cell can be turned into something.
After the separation, the cell with qualified capacity will enter the post-process, including checking the appearance, gluing, edge voltage detection, pole ear conversion welding, etc., which can be increased or decreased according to the needs of customers. Finally, OQC inspection, and then packaging and shipping.
Mind you, it‘s just the batteries so far. The cells are sent to the Pack factory for further processing, including soldering circuit boards, packaging and so on. The downstream of the Pack factory is various user manufacturers, such as Apple, Lenovo, Huawei, they will take the battery Pack to the terminal, and then come to the hands of our consumers.
