What is a 18650 lithium ion battery? How does it compare with other batteries

18650 actually refers to the battery's external specifications. It is a standard battery model set by the Japanese SONY company in order to save costs. Among them, 18 indicates a diameter of 18mm, 65 indicates a length of 65mm, and 0 indicates a cylindrical battery. Compared with other batteries, the laminated lithium-ion battery is far from mature. The common ones are square batteries, soft-pack batteries, and even the size, size, and position of the tabs are not uniform. The production of battery manufacturers The technology can't meet the conditions, most of which are controlled by humans, and the consistency of the battery cannot reach the level of the 18650 battery. If the consistency of the battery fails to meet the requirements, the management of a large number of battery strings and battery packs formed in parallel will not allow the performance of each battery to be better played, and 18650 batteries can solve this problem. In summary, the cell capacity of the 18650 battery is small, and the number of cells required will be a lot (ModelS has 7104), but the consistency is very good; the capacity of the stacked battery can be made larger (20Ah to 60Ah), single The number of bodies can be reduced, but the consistency is poor. In contrast, at this stage, it is difficult to invest a lot of manpower and material resources to improve the production process of laminated batteries together with battery suppliers. Therefore, when developing Roadster and ModelS, Tesla's only option is to buy batteries from the market and develop its own battery system. In contrast, the technical difficulty of developing a battery system that manages more than 6000 cells with good consistency is less than that of developing a battery system with more than 200 cells with poor consistency. Even if the number of single batteries increases, if the performance of these batteries is reliable, it is still easier to manage. 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: How to conduct a safety test for lithium-ion batteries?