The development process and technological development direction of power lithium-ion batteries

The development process and technical development direction of power lithium-ion batteries are decomposed according to customer needs, and the design is gradually decomposed. Each process will eventually be transformed into file input and output. The product design process is described in detail below. In the most basic design, the negative electrode is 1-2mm wider than the positive electrode, and the diaphragm is 2-4mm wider than the negative electrode. In order to ensure that the uneven battery is not short-circuited, the stack is equivalent to several small electrodes in parallel, and the winding is equivalent to a large electric pole. Because of the quality of the light aluminum plastic film and the high utilization of the internal space, the soft-coated battery is suitable for battery energy The development of high density, and the limitation of the internal space of the metal casing, and the general energy density is slightly lower than that of soft-coated batteries. Because aluminum batteries are protected by a metal casing, they are more secure, while flexible packaging batteries can only rely on the function of the data itself to pass the safety test, which now seems more difficult. In terms of process difficulty, since the soft pack battery is a large number of small poles, it has high requirements for die-cutting equipment, and is prone to self-discharge and partial micro-short circuits. Due to internal space limitations, there is less free electrolyte and the circulation function may be slightly worse. The wound battery is relatively better, has a surplus, and is easy to complete automated processing. In terms of cost, because the welding of the winding battery shell is required, the cost is slightly higher, and the soft battery does not involve laser welding. The focus is on packaging and low equipment investment. According to the internal space to calculate the battery, the battery is negative, the diaphragm layer, according to the case of occupational behavior, the parameters related to the test data are based on past experience to verify the compaction density, information function, and auxiliary materials of the function (including The type of platform developed on the basis of SBR, CMC verification, PVDF, conductive agent, etc.), the final technology development should also match the information, and finally the control method and process flow chart can be obtained. Nowadays, in order to shorten the time, manufacturers combine experimental verification and process development, but this is often risky, after all, the data system itself is carried out with the development of skills. Each function of each data has corresponding testing specifications, and some functional indicators of the positive and negative electrodes are directly related to the functional indicators of the battery. However, there is currently no suitable model to simulate the use of forward electrochemistry, and it can only be repaired based on the existing relevant experience data. However, the increase in the Co ratio will result in a decrease in battery parameters a and c, and the increase in c/a will result in a decrease in capacity. However, an excessively high manganese content will reduce the capacity of the data map, prone to spinel phase, and destroy the hierarchical structure of the data. However, if the Ni content is too high, a mixed discharge effect will occur with Li+, resulting in the deterioration of the cycle function and the multiplier function. If the pH value of the high nickel data is too high, it will affect the actual use. As the nickel content increases, the data capacity increases, but the thermal stability of the data gradually decreases. Mn can serve to stabilize the structure, but Ni cannot. As the temperature increases, the positive electrode Ni transfers to the Li layer through the tetrahedral position in the delithium state, causing structural collapse and thermal stability problems. The data structure changes from layered salt to spinel, and continuously to rock salt. Every change is aerobic release, which accelerates the heat loss of data. Regarding most data manufacturers that do not process the precursors themselves, there are specialized manufacturers for the precursors. The data purchased by the original data manufacturers from the precursor manufacturers are sintered, and the control conditions are different, and the data functions obtained are also different. During the charging and discharging process of NCA, serious gas appears, which causes the battery to swell and deform, and the cycle and storage life are reduced, which brings safety risks to the battery. Therefore, NCA's positive data is generally used to manufacture 18650 cylindrical batteries. 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: Daily maintenance of the sweeper lithium battery pack