Analysis and Answers of Abnormal Quality Problems in the Process of Battery Production

Analysis and solution of abnormal quality problems in the battery production process 1. What is the manufacturing process of lithium-ion batteries? (1) Paste: mix the positive and negative active materials with a special solution and rubber powder, and mix them evenly at high speed. The paste has two kinds of substances, positive and negative. (2) Coating: The slurry is uniformly coated on the surface of the metal foil, and then dried to make positive and negative sheets. (3) Film making: Cut the coated cloth to the size required by the process, press the sheet, and re-weld the tabs. (4) Assembly: The assembly process of the battery is to place the positive plate, the separator, and the negative plate in sequence to wind the battery The electrode core is packed into the packaging film, and then electrolyte is injected and sealed. (5) Transformation: Use special battery charging and discharging equipment to perform charge and discharge tests on finished batteries, and test each battery. The qualified finished batteries are screened and delivered. (6) Packaging: According to customer requirements, the battery pack is shipped. 2. One of the most strictly controlled factors in the production of lithium-ion batteries is water. Why? Answer: As long as there is a small amount of water in the battery, gas will appear in the battery, which will reduce the capacity of the battery and the discharge effect is poor. Therefore, the water must be strictly controlled in the production process. 3. What part of the production process may introduce water? How to effectively control it? Answer: Before the sealing liquid of the battery is injected, the cells are required to be very dry, and the moisture content of the cells after vacuum drying is less than 5% of the relative humidity of the air, because the air humidity Generally 60%~90%, therefore, as long as contact with air cells to absorb water. After special treatment, the air humidity in the injection room can be controlled below 25%, but still higher than the cell water content. Therefore, the injection cavity should also shorten the operating time and reduce the exposure time of the cells in the air. In order to effectively control the moisture, control from the production rod, including paint drying, drying bridge drying, and control of the humidity in the workshop, until the assembly and cutting of the diaphragm dry and control Workshop humidity. In short, everything must be dry. Before entering the workshop, we must wash our hands, dry our hands, and wear masks to prevent saliva from spraying on telephone poles. 4. What happens if the storage time is too long? Answer: If the storage time of the pole piece is too long, the battery performance will decrease. In addition, dust, dust and other impurities will appear on the pole after long-term storage, causing self-discharge, micro-short circuit and other consequences. 5. What's the problem with the powder floating on the pole? Answer: There are floating powder plates that meander to the battery and after the liquid is injected, the floating powder will move the battery and the electrolyte and some of the problems, such as membrane defects, may cause the battery There is a short circuit, self-discharge problem. 6. What is the purpose of pressing the positive film and the negative film? Answer: Make the contact between the active material and the conductive foil and the active material itself close, reduce the thickness of the electrode, increase the utilization rate of the battery volume, and reduce the internal resistance. This improves the battery's high-current discharge performance. 7. What effect does the thickness of the plate have on the battery performance? Answer: The thickness of the extreme pressure sheet does not meet the requirements, and the thickness of the battery does not meet the requirements first. In addition, the thickness of the extreme pressure sheet and the degree of close contact with the active material will also be different, which will cause differences in battery performance. 8. Is there any problem with the oily substance attached to the telegraph pole? Answer: The oily substance attached to the telegraph pole may cause the electrolyte to be impermeable and make the reaction of the active substance worse. In addition, oily substances can also cause impurities in the battery, and some reactions that damage the battery performance will occur in the battery, resulting in a decrease in battery performance. 9. What is the impact of electrode plate dust removal on battery performance? Answer: The electrode plate dust removal will result in insufficient battery capacity. In addition, the dust removal of the negative plate will also cause safety problems, which may short-circuit the dendrites of the battery and cause fire. 10. What effect do hard spots, fingerprints and uneven surfaces have on the battery? A: There are hard spots on the surface of the strut plate. When the piezoelectric material is wound, the hard spots on the diaphragm are easy to penetrate. Statement: Some pictures and content of the articles published on this site are from the Internet. If there is any infringement, please contact to delete. Previous post: Comparison of various power lithium-ion batteries