With the promotion of energy conservation and environmental protection in society, more and more environmentally friendly products are applied to the market. In the battery industry, ternary lithium batteries quickly occupied the market by virtue of many advantages, and gradually replaced traditional lead-acid batteries. For traditional batteries, the ternary lithium battery has the advantages of long life, energy saving, environmental protection, pollution-free, low maintenance cost, complete charge and discharge, and light weight. In general, the ternary lithium battery has a long life, to what extent?
Ternary lithium battery
What is a ternary lithium battery?
In nature, lithium is the lightest metal with the smallest atomic mass. Its atomic weight is 6.94g/mol, ρ=0.53g/cm3. Lithium is chemically active and easily loses electrons and is oxidized to Li+. Therefore, the standard electrode potential * is negative, -3.045V, and the electrochemical equivalent * is 0.26g/Ah. These characteristics of lithium determine that it is a kind of Materials with very high specific energy. Ternary lithium 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 integrates 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 methods to synthesize nickel Co-manganese and other multi-element synergistic composite lithium intercalation oxides. It is a lithium ion rechargeable battery that has been widely researched and applied.
Ternary lithium battery life
The so-called lithium battery life refers to that the capacity of the battery decays to 70% of the nominal capacity (the battery capacity at room temperature 25°C, standard atmospheric pressure, and discharged at 0.2C) after a period of time, which can be considered as the end of life. In the industry, the cycle life is generally calculated based on the number of cycles of fully charged and discharged lithium batteries. In the process of use, an irreversible electrochemical reaction occurs inside the lithium battery, which leads to a decrease in capacity, such as the decomposition of the electrolyte, the deactivation of active materials, the collapse of the positive and negative structure, and the reduction in the number of lithium ions inserted and extracted, etc. . Experiments have shown 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 and more energy can be released.
The theoretical life of a ternary lithium battery is about 800 cycles, which is medium among commercial rechargeable lithium 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 ternary battery cells. However, after the batteries are assembled into a battery pack, due to consistency problems, the main voltage and internal The resistance cannot be exactly the same, and its cycle life is about 400 times. The manufacturer recommends that the SOC use window is 10%~90%. Deep charging and discharging is 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 batteries are frequently discharged in high-rate and high-temperature environments, the battery life will be greatly reduced to less than 200 times.
The number of life cycles of lithium batteries is determined according to battery quality and battery materials:
1. The cycle times of ternary materials are about 800 times.
2. The number of cycles of lithium iron phosphate battery is about 2500.
3. There is a difference between the cycle times of genuine batteries and defective batteries. Genuine batteries are designed and produced according to the cycle number in the battery manufacturer's specification, while the cycle times of defective batteries may sometimes be less than 50 times.
Ternary lithium battery life
The so-called lithium battery life refers to that the capacity of the battery decays to 70% of the nominal capacity (the battery capacity at room temperature 25°C, standard atmospheric pressure, and discharged at 0.2C) after a period of time, which can be considered as the end of life. In the industry, the cycle life is generally calculated based on the number of cycles of fully charged and discharged lithium batteries. In the process of use, an irreversible electrochemical reaction occurs inside the lithium battery, which leads to a decrease in capacity, such as the decomposition of the electrolyte, the deactivation of active materials, the collapse of the positive and negative structure, and the reduction in the number of lithium ions inserted and extracted, etc. . Experiments have shown 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 and more energy can be released.
The theoretical life of a ternary lithium battery is about 800 cycles, which is medium among commercial rechargeable lithium 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 ternary battery cells. However, after the batteries are assembled into a battery pack, due to consistency problems, the main voltage and internal The resistance cannot be exactly the same, and its cycle life is about 400 times. The manufacturer recommends that the SOC use window is 10%~90%. Deep charging and discharging is 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 batteries are frequently discharged in high-rate and high-temperature environments, the battery life will be greatly reduced to less than 200 times.
Juda Lithium Battery has been manufacturing battery packs, ternary lithium batteries, lithium iron phosphate batteries, lithium iron manganate batteries, lithium ion batteries, etc. for a long time. With a wide range of products and high quality, Xindongli is a top-ranked battery brand in China.
In today's lithium battery market, ternary lithium batteries are widely used. They are moderate in terms of performance and low in price. Therefore, using ternary lithium batteries is the most cost-effective. People always say that the ternary lithium battery has a long life. How long is it? Ternary polymer lithium battery refers to a lithium battery that uses lithium nickel cobalt manganate (Li (NiCoMn) O2) as the cathode material. The precursor product of the ternary composite cathode material is nickel salt, cobalt salt, and manganese salt. As raw materials, the ratio of nickel, cobalt and manganese inside can be adjusted according to actual needs. The battery with ternary material as the positive electrode is safer than lithium cobalt oxide battery, but the voltage is too low for use in mobile phones (the cut-off voltage of mobile phones is generally around 3.4V ) There will be an obvious feeling of insufficient capacity.
Ternary lithium battery performance:
The material with relatively balanced capacity and safety has better cycle performance than normal lithium cobalt oxide. In the early stage, its nominal voltage was only 3.5-3.6V due to technical reasons, and its use range was limited. But up to now, with the formulation of With continuous improvement and perfect structure, the nominal voltage of the battery has reached 3.7V, and its capacity has reached or exceeded the level of lithium cobalt oxide batteries.
1. High voltage platform. Voltage platform is an important indicator of battery energy density and determines the basic performance and cost of the battery. Therefore, the selection of battery materials is of great significance. The higher the voltage platform, the greater the specific capacity, and certainly the same size, weight, and even the same ampere-hour battery, the higher the voltage platform of the ternary material lithium battery has a longer range. The voltage platform of the ternary material is significantly higher than that of lithium iron phosphate, the high line can reach 4.2 volts, and the discharge platform can reach 3.6 or 3.7 volts.
2. High energy density
3. High tap density
