How many times are there in the life cycle of a ternary lithium-ion battery?

As the endurance range of new energy vehicles is limited, how to improve endurance has affected the entire market. In the battery industry, ternary lithium-ion batteries quickly occupied the 3C, automotive and other markets with their many advantages, and gradually replaced traditional lead-acid batteries. Regarding traditional batteries, ternary lithium-ion batteries have the advantages of long life, energy saving, environmental protection, pollution-free, low maintenance cost, complete charge and discharge, and light weight. In some publicity materials, some people think that ternary lithium-ion batteries have long life. ,Is it really? How many times does it have a life cycle? Let us uncover the truth. What is a ternary lithium ion battery? In nature, lithium is the lightest metal with the smallest atomic mass. Lithium is chemically active and easily loses electrons and is oxidized to Li+. The standard electrode potential is -3.045V, and the electrochemical equivalent is 0.26g/Ah. Lithium These characteristics determine that it is a material with a high specific energy. Ternary lithium ion battery refers to a lithium secondary battery that uses three transition metal oxides of nickel, cobalt and manganese as the positive electrode material. It fully combines the good cycle performance of lithium cobalt oxide, the high specific capacity of lithium nickelate and the high safety and low cost of lithium manganate. It uses molecular level mixing, doping, coating and surface modification to synthesize nickel. Cobalt and manganese and other multi-element synergistic composite lithium intercalation oxides are currently widely studied and used in lithium ion rechargeable batteries. The theoretical life is only a medium-level ternary lithium-ion battery. The life of a ternary lithium-ion battery is calculated by the proportion of the capacity attenuation after a certain degree of use. The pen will end until the capacity life is zero. The industry algorithm generally discharges the ternary lithium-ion battery once after being overcharged, which is called cycle life. During use, the irreversible chemical reaction inside the lithium-ion battery will cause the battery capacity to decrease, such as improper use, or use at extremely high or low temperatures. For example, the analysis of electrolyte, the deactivation of active materials, the collapse of the positive and negative electrode structure lead to a decrease in the number of lithium ions inserted and extracted, and so on. The test shows that a higher rate of discharge will lead to a faster attenuation of capacity. If the discharge current is lower, the battery voltage will be close to the equilibrium voltage, which can release more energy. The theoretical life of the ternary lithium-ion battery is 1200 times of complete charge and discharge, that is, the complete cycle life. According to the frequency of use, it is fully charged and discharged once in three days and 120 times a year. The service life of the ternary lithium-ion battery reaches ten. Years, even if there is loss during use or the number of charging and discharging days is reduced, it can reach eight years. Note that here is the capacity life. After eight years, the capacity of the ternary lithium-ion battery will still be more than 60%. This is where the standard lies. The theoretical life of ternary lithium-ion batteries is medium among commercial rechargeable lithium-ion batteries. Lithium iron phosphate is about 2,000 cycles, while lithium titanate is said to be able to reach 10,000 cycles. At present, mainstream battery manufacturers promise more than 500 times (charge and discharge under standard conditions) in the specifications of their processed ternary batteries. However, after the batteries are assembled into a battery pack, due to consistency issues, the most important factors are voltage and internal The resistance can not be exactly the same, and its cycle life is about 400 times. The manufacturer recommends that the SOC use window is 10%~90%. Deep charge and discharge are not recommended, otherwise it will cause irreversible damage to the positive and negative structure of the battery. If it is calculated by shallow charge and shallow discharge, the cycle life will be at least 1000 times. In addition, if lithium-ion batteries are often discharged in high-rate and high-temperature environments, the battery life will be drastically reduced to less than 200 times.