Analysis of some difficulties in power lithium-ion battery packaging and welding

1. Welding of power lithium-ion batteries Generally, the thickness of the aluminum shell of power lithium-ion batteries is required to be no more than 1.0 mm. At present, mainstream manufacturers mainly use two kinds of 0.6mm and 0.8mm. Welding methods are mainly divided into top welding and side welding. The main advantage of side welding is that it has a small impact on the inside of the cell, and spatter will not easily enter the inside of the cover. Since the welding may cause bumps, which will have a slight impact on the subsequent process assembly, the side welding process has a high degree of stability of the laser, the cleanliness of the material, and the matching gap between the top cover and the aluminum case of the power lithium ion battery. Requirements. As the top welding process is welded on one surface, a more efficient galvanometer scanning welding method can be used, but the requirements for the previous process of the housing and positioning are very high, and the requirements for the automation of the equipment are high. 2. Welding of power lithium-ion battery aluminum shells At present, power lithium-ion battery aluminum shells account for more than 90% of the entire power lithium-ion battery. The laser welding of aluminum is more difficult, and it will face the problems of raised surface of the weld mark, pores, fire problems, internal air bubbles, etc. Surface protrusions, pores, and internal bubbles are fatal injuries of laser welding. Many applications have to be stopped or avoided due to these reasons. Many battery manufacturers will be troubled by this in the early stage of research and development. The reason is that the fiber core diameter is too small or the laser energy is set too high. There are many factors that cause explosions (also known as splash, Splash), such as the cleanliness of the material, the purity of the material itself, and the characteristics of the material itself. The decisive use is the stability of the laser. In power lithium ion battery welding, the welding process technicians will select the appropriate laser and welding process parameters according to the customer's battery material, shape, thickness, and tensile requirements, including welding speed, waveform, peak value, welding head tilt angle, etc. Reasonable welding process parameters to ensure that the final welding effect meets the requirements of power lithium-ion battery manufacturers. 3. Welding of square power lithium-ion batteries Due to factors such as the matching accuracy of the incoming materials, the welding of square batteries is most likely to have problems at the corners. We must continue to explore based on the actual situation and adjust the welding speed to deal with this type of problem. The circular battery does not have this problem, but the subsequent integration into a battery module is more difficult. The difficulty of welding power lithium-ion battery is shared here for you. As long as we know these difficulties in power lithium-ion battery welding, we will be on alert one by one, and we believe that we will be able to break through the welding difficulties. Disclaimer: Some pictures and content of articles published on this site are from the Internet. If there is any infringement, please contact to delete. Previous post: What are the common functions of the power lithium battery protection board