Introduction to the advantages and disadvantages of 18650 batteries

18650 actually refers to the appearance standard of the battery. It is a standard battery type set by the Japanese SONY company in order to save costs. Among them, 18 indicates that the diameter is 18mm, 65 indicates that the length is 65mm, and 0 indicates that it is a cylindrical battery. 18650 batteries originally referred to nickel-metal hydride batteries and, because nickel-metal hydride batteries are now less used, they now refer to lithium-ion batteries. The nominal voltage of a single cell of 18650 lithium-ion battery is generally 3.6V or 3.7V; the minimum discharge termination voltage is generally 2.5~2.75V. The common capacity is 1200～3300mAh. The 18650 battery is the earliest, most sophisticated and stable lithium-ion battery, which is widely used in electronic products. Over the years, Japanese manufacturers have accumulated a lot of relevant experience in the processing technology of 18650 batteries, so that the consistency and safety of the 18650 batteries produced have reached a very high level. In contrast, laminated lithium-ion batteries are far from sophisticated. The common ones are square batteries and soft-pack batteries. Even the size, size, and position of the tabs are not consistent. The processing technology of the battery manufacturer cannot meet the conditions. Most of them are controlled by humans, and the consistency of the battery is not up to the level of the 18650 battery. If the consistency of the battery fails to meet the requirements, the handling of battery packs composed of many batteries in series and parallel will not allow the function of each battery to be better utilized, 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, it is difficult to invest a lot of manpower and material resources to improve the processing technology of stacked batteries together with battery suppliers at this stage. Therefore, when developing Roadster and ModelS, Tesla's only option was to buy batteries from the market and develop its own battery system. Compared with the development of a battery system with more than 6,000 cells with very good consistency, and the development of a battery system with more than 200 cells with very poor consistency, the technical difficulty of the former should be lower. Even if the number of single batteries increases, if the functions of these batteries are reliable, it is still easier to handle. 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 article: Do you know what are the functional requirements of echelon lithium iron phosphate batteries?