What are the important factors that affect the cycle life of lithium-ion battery packs?

1. Design and manufacturing process In the battery design process, the choice of materials is the most important factor. The performance characteristics of the different materials are different, and there are also gaps in the performance of the batteries developed. The reincarnation function of the positive and negative material matching is good, and the reincarnation life of the battery will be long. Generally speaking, in the design and assembly process, the capacity of the negative electrode is generally required to be excessive relative to the positive electrode. If the amount is not exceeded, the negative electrode will precipitate lithium during the charging process, forming lithium dendrites, thereby affecting the safety. There is too much excess of the negative electrode relative to the positive electrode, and the positive electrode is probably too delithic, causing the layout to collapse. The type and amount of electrolyte also affect the battery life. The manufacturing process of lithium-ion battery packs mainly includes: positive and negative electrode ingredients, coating, sheeting, winding, shelling, liquid injection, sealing, forming, etc. In the battery production process, the requirements for each step of the process are very strict. Any process that is not well controlled will probably affect the battery cycle performance. 2. Lithium-ion battery material aging and decline The process of charging and discharging cycles of lithium-ion battery packs is the process of lithium ions being deintercalated and moved back and forth between the positive and negative materials through the electrolyte. In the cycle of lithium-ion battery packs, in addition to redox reverberations at the positive and negative electrodes, there are also a large number of secondary reverberations. If the secondary reverberation of lithium-ion batteries can be reduced to a low level, so that lithium ions can always smoothly go back and forth between the positive and negative materials through the electrolyte, the cycle life of lithium-ion batteries can be increased. The nature of the positive and negative current collectors will also affect the battery capacity and cycle life. The commonly used current collector materials for the positive and negative electrodes of lithium-ion battery packs are aluminum and copper, both of which are perishable metal materials. After the current collector is corroded, a passivation film is formed, poor adhesion, partial corrosion (pitting) and overall corrosion increase the internal resistance of the battery, resulting in capacity loss and low discharge efficiency. The adhesion and corrosion resistance can be strengthened by pretreatment methods such as acid-alkali etching and conductive coating. 3. The charging and discharging system in the reincarnation process. The use process of lithium-ion battery packs is the process of charging and discharging cycles, the size of the charge and discharge current, the choice of charge and discharge cut-off voltage, and which charge and discharge method to recycle. The reincarnation life span also has a very important impact. Where blindly increase the working current of the battery, add new charging cut-off voltage, lower discharge cut-off voltage and other cities, the performance of lithium-ion battery packs is reduced. The difference in the charge-discharge cut-off voltage of lithium-ion batteries in different electrochemical systems. In the process of lithium-ion battery charging, if the charging cut-off voltage is higher, it is considered that overcharge has occurred. When a lithium-ion battery is overcharged, the excess lithium ions extracted from the positive electrode will be deposited or embedded on the negative electrode, and the deposited active lithium easily reacts with the solvent, releasing heat to increase the battery temperature. When the discharge voltage of the lithium-ion battery is lower than the discharge cut-off voltage, overdischarge is formed. In the process of over-discharge, lithium ions will be too detached from the negative electrode, and it will be harder to re-insert it during the next charge. The discharge capacity and charge-discharge efficiency of lithium-ion batteries are greatly reduced in the future cycle of over-discharge. In addition, lithium-ion batteries will most likely fuse under high current conditions, and equipment components may also be damaged. 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: Do you know how to use lithium-ion battery electric vehicles correctly?