Analyze the service life, advantages and disadvantages of ternary lithium batteries

The service life, advantages and disadvantages of ternary lithium batteries What is a ternary lithium battery? In nature, lithium is the lightest metal with the smallest atomic mass. Its relative atomic mass is 6.94g/mol, u003d 0.53g/cm3. Lithium is chemically active and easily loses electrons and is oxidized into lithium ions. Therefore, the standard electrode potential is the most negative, -3.045v, and the electrochemical equivalent is the smallest, 0.26g/Ah. These characteristics of lithium determine that it is a material with a very high specific energy. The ternary lithium battery refers to a lithium secondary battery that uses nickel-cobalt-manganese transition metal oxide as the negative electrode material. The good cycle performance of lithium cobalt oxide, the high specific capacity of lithium nickelate, the high safety and low cost of lithium manganate are fully synthesized, and the composite intercalation is synthesized through molecular level mixing, doping, coating and surface modification.式lithium oxide. It is a kind of lithium ion rechargeable battery that is widely researched and applied. Life of a ternary lithium battery The so-called lithium battery life refers to the battery life after the battery's capacity decays to 70% of the nominal capacity (room temperature 25°C, standard atmospheric pressure, discharge capacity 0.2°C) after a period of use. The end. In the industry, the cycle life is generally calculated by the number of cycles that a lithium battery is fully charged. In the process of use, an irreversible electrochemical reaction occurs inside the lithium battery, resulting in a decrease in capacity, such as the decomposition of electrolyte, the deactivation of active materials, and the collapse of anode and cathode structures, resulting in a reduction in the number of lithium ion intercalation and unembedded. . Experiments have shown that higher power discharge leads to faster capacity decay. If the discharge current is low, the battery voltage will be close to the equilibrium voltage, releasing more energy. The theoretical life of a ternary lithium battery is about 800 times, which makes it a medium for commercial rechargeable lithium batteries. Lithium iron phosphate has about 2,000 cycles, while lithium titanate is said to be able to reach 10,000 cycles. Currently, mainstream battery manufacturers promise more than 500 times in their ternary battery specifications (charge and discharge under standard conditions). However, after the battery is packaged into a battery pack, the important reason is that the voltage and internal resistance cannot be exactly the same, and the cycle life is about 400 times. The manufacturer recommends that the SOC use window is 10%-90%, and deep charging and discharging is not recommended, otherwise it will cause irreversible damage to the positive and negative structure of the battery. If the calculation method of shallow charge and shallow discharge is adopted, its cycle life is at least 1000 times. In addition, if the battery is continuously discharged under high power and high temperature, the battery life of the lithium battery can be reduced to less than 200 times. Advantages and disadvantages of ternary lithium battery The ternary lithium battery is a battery with balanced capacity, safety and reliability, and excellent overall performance. The important functions, advantages and disadvantages of the three metal elements are as follows: Co3+: Reduce the occupation of cation mixing space, stabilize the layered structure of the material, reduce the impedance value, increase the conductivity, and improve the circulation and multiplier performance. Ni2+: The capacity of the material can be added (the energy density of the material can be added). However, due to the similar radii of lithium and nickel, too much nickel can also cause dislocation of lithium and nickel. Mn4+: Not only can reduce material costs, but also improve the safety and stability of materials. However, if the Mn content is too high, the spinel phase is easy to appear, destroying the layered structure, resulting in a decrease in capacitance and cycle attenuation. The biggest advantage of high energy density is the ternary lithium battery. This platform is an important indicator of battery energy density and voltage, which determines the basic performance and cost of the battery. The higher the voltage platform, the larger the specific capacity, so the same volume , Weight, and even the same ampere hour battery, the high-voltage platform ternary material lithium battery has a longer life. The discharge voltage platform of single ternary lithium battery is as high as 3.7v, lithium iron phosphate is 3.2v, and lithium titanate is only 2.3v. Therefore, from the perspective of energy density, the ternary lithium battery has absolute advantages relative to lithium iron phosphate, lithium manganate or lithium titanate. 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: What is a lithium battery pack? What is a large-capacity lithium battery pack?