Analyze the structure of soft pack lithium battery and the difference with aluminum shell battery

The key materials used in the soft pack lithium battery structure The positive electrode material, negative electrode material and barriers used in the soft pack lithium battery are not much different from the traditional steel shell and aluminum shell lithium batteries. The biggest difference lies in the soft packaging material (aluminum-plastic composite film). ), this is the most critical and technically difficult material in the soft pack lithium battery. Flexible packaging materials are usually divided into three layers, namely the outer barrier layer (usually the outer maintenance layer composed of nylon BOPA or PET), the barrier layer (middle layer aluminum foil) and the inner layer (multifunctional high barrier layer). The packaging materials and structure of the soft pack battery give it a series of advantages. Based on the summary of the electric Zhijia Volkswagen, for example, the safety performance is good. The soft pack battery is packaged with aluminum-plastic film in the structure. When a safety problem occurs, the soft pack battery is generally It will swell and crack, instead of exploding like a steel shell or aluminum shell battery; light weight, the soft pack battery is 40% lighter than a steel shell lithium battery of equal capacity, and 20% lighter than an aluminum shell lithium battery; internal resistance Small, the internal resistance of the soft pack battery is smaller than that of the lithium battery, which can greatly reduce the self-consumption of the battery; the cycle performance is good, the cycle life of the soft pack battery is longer, and the attenuation of 100 cycles is 4% to 7% less than that of the aluminum case ; The design is flexible, the shape can be changed to any shape, and it can be thinner. It can be customized according to customer needs and develop new types of batteries. The disadvantages of soft-pack batteries are poor consistency, high cost, and easy leakage. High cost can be solved by large-scale production, and liquid leakage can be solved by improving the quality of aluminum plastic film. The difference between soft-pack lithium batteries and aluminum-shell batteries is in areas with higher consumption levels, such as European and American countries, where the use of soft-pack lithium batteries has advantages. In most developing countries, such as India and the Middle East, aluminum shell batteries have significant advantages. The overlap of the use categories is currently the most used high-end smart phone market. For example, the soft-pack lithium battery represented by Apple and the aluminum shell battery represented by Samsung are used equally. In the meantime, Samsung mobile phones generally use large-scale 4.8 inches, with an average battery capacity of about 2700mAh, while the average battery capacity of Apple mobile phones is about 1700mAh. There are no technical barriers in the industry, and soft-pack lithium batteries still have many technical problems to be solved, especially in terms of battery cycle expansion indicators, which most battery cell factories have not solved. The degree of automation in the production of aluminum shell batteries is higher than that of soft-packed lithium batteries. Therefore, the impact of human factors on product consistency is reduced to a certain extent, and labor costs are saved at the same time. In terms of production costs, aluminum shell battery materials have been fully localized, while aluminum-plastic film materials for soft-pack lithium batteries still need to be imported, and the technical requirements for battery materials for aluminum-shell batteries are lower than soft-pack lithium batteries. Therefore, the overall data cost is about 10% lower than that of a soft-pack lithium battery under the same capacity. In addition, the production of products is simple, reliable, and has significant cost advantages. 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: Common 18650 lithium battery classification and analysis of advantages and disadvantages