18650 battery pack 3.7v

　　Introduction to the knowledge points of the 18650 lithium battery production process

　　The theoretical life of the 18650 lithium battery is 1000 cycles of charging. Due to the large capacity per unit density, most of them are used for laptop batteries. In addition, because 18650 has very good stability at work, it is widely used in various electronic fields: often used in high-end glare flashlights, portable Power supplies, wireless data transmitters, electric thermal clothing, shoes, portable instruments, portable lighting equipment, portable printers, industrial instruments, medical instruments, etc.

　　The theoretical life of the 18650 lithium battery is 1000 cycles of charging. Due to the large capacity per unit density, most of them are used for laptop batteries. In addition, because 18650 has very good stability at work, it is widely used in various electronic fields: often used in high-end glare flashlights, portable Power supplies, wireless data transmitters, electric thermal clothing, shoes, portable instruments, portable lighting equipment, portable printers, industrial instruments, medical instruments, etc. So, what is the production process of 18650 lithium battery? Today Shenzhen will talk to you about this knowledge point, so that more people can have a deep understanding of 18650 lithium battery. (1) Bake for 12 hours under the condition of constant temperature and vacuum degree of -0.09MPa, the main purpose is to dry the moisture of the battery cell. (2) Liquid injection. Inject the vacuum-baked cell into the glove box filled with Ar gas. The amount of liquid injection varies according to the design of the battery. The battery must be weighed before and after liquid injection. In order to judge whether the injection volume is appropriate or not. (3) Welding tabs Weld the positive tab (aluminum strip) and the negative tab (nickel strip) to the scraper positions of the positive and negative tabs with an ultrasonic welding machine. Pay attention to prevent welding deviation, welding dislocation, and false welding. (4) Bottom welding first put the insulating gasket into the steel shell, then put the wound battery core into the steel shell, and weld the negative tab to the bottom of the steel shell with a spot welder. Check the outer surface of the bottom of the steel shell, pick out yellow spots, black spots, defects, fires and other poor appearances, and try to pull the tabs to pick out batteries that are not firmly spot welded, such as fires, weak welding, and desoldering. (5) Sealing First use a spot welding machine to spot weld the steel shell and cap of the battery, and then use a laser welding machine for continuous laser welding. Laser welding should ensure accurate positioning, and the welded parts are clean. It is strictly forbidden to cause deformation or damage to the battery. Check after welding, and repair welding for defective batteries such as welding holes and explosions. (6) Winding Place the ion exchange membrane on the winding needle evenly, and the front end protrudes 2-5mm from the winding needle. There should be no wrinkles at the four corners of the pole piece, and the pole piece should not be dropped. If it is too long, the double-sided tape is misaligned left and right, and the tape does not cover the solder joints, etc., the positive electrode material must hug the negative electrode material, the pole piece cannot be rolled, and the front end of the pole piece must be inserted to the top. Check the winding defects: the ion exchange membrane is not uniform, that is, the positive and negative electrodes exceed the exchange membrane; The top of the exchange membrane is not overlapped, there is still a distance; the exchange membrane is too tightly attached to the tail of the negative pole; the positive aluminum strip and the negative nickel strip are too long and too short; the end of the battery cell is not properly wrapped with tape; Wide or narrow; the exchange membrane is not flattened and wrinkled; the positive electrode is curled; the positive electrode sheet is not curled or missing; the exchange membrane is not fully aligned with the end of the negative electrode sheet; the inner and outer electrode sheets are dislocated.