Analysis Of The Life Of Ternary Lithium Battery

- Aug 24, 2018-

Ternary lithium battery overview

Since the electrolyte materials constituting the lithium battery are different, the lithium ion battery is also classified into a ternary lithium battery and a liquid lithium ion battery. The ternary lithium ion battery is the same as the positive and negative materials of the liquid lithium ion battery, and the battery works similarly, and the electrolytes are different from each other. The ternary lithium battery is light in weight, strong in energy storage capacity, good in discharge performance, and can cause various shapes and has a long life. The electrolyte of the ternary lithium battery is a solid electrolyte. Compared with the liquid electrolyte of the liquid lithium ion battery, the ternary lithium battery can cause various shapes to improve the specific capacity of the battery

With the increasing global pollution, energy conservation and environmental protection has become the top priority of social development. At present, China has vigorously promoted environmental protection and introduced some related policies. Therefore, there are more and more environmental protection equipment on the market. Including the reduction of gasoline vehicles, the market launch of new energy vehicles, and products such as charging treasures are all environmentally friendly batteries. That is, lithium batteries, lithium batteries, compared with the traditional lead acid point, have a short charging time, long cycle life, energy saving and environmental protection, no pollution, light weight, long service life and other characteristics. Said that it has a long life and where is it?

Under the international unified standard, the battery life is not expressed by time, but by the number of cycles, that is, the complete discharge of the electricity once, the general lithium battery is between 300-500 times, A product ternary battery can Up to 800 times. Therefore, the quality of the battery of the selected battery supplier will be guaranteed and the service life will be longer.


How long is the life of the ternary lithium battery?

If a lithium-ion battery is used in a high-temperature environment, such as a temperature above 350C, the amount of battery stored will continue to decrease, resulting in a battery that does not last as long as it is in a normal temperature environment. When the battery is charged in such a high temperature environment, the battery will be damaged to a large extent, thereby affecting the service life of the battery. Even charging in a hot environment can cause different degrees of damage to the battery, so you should try to avoid charging the battery in a high temperature environment. If the battery is charged in a low temperature environment, such as in an environment below 40C, it will also cause damage to the battery.

If you do not charge the ternary lithium-ion battery for a long time, it will reduce its life. The ternary lithium-ion battery needs to reach its ideal service life while the electrons remain flowing for a long time. The commercial production technology of ternary lithium-ion batteries in the world is not very mature, and now the market share is not high.

The theoretical life of a ternary lithium battery is about 800 cycles, which is medium in commercial rechargeable lithium batteries. Lithium iron phosphate is about 2000 times, and lithium titanate is said to reach 10,000 cycles. At present, the mainstream battery manufacturers promise more than 500 times in the ternary battery specifications produced by them (charge and discharge under standard conditions), but after the batteries are assembled into battery packs, due to consistency problems, mainly 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 be 10%~90%. It is not recommended to carry out deep charge and discharge. Otherwise, it will cause irreversible damage to the positive and negative structures of the battery. If it is calculated by shallow charge and shallow release, the cycle life is at least 1000 times. In addition, if the lithium battery is often discharged in a high rate and high temperature environment, the battery life will be greatly reduced to less than 200 times.


What is a ternary lithium battery?

In nature, lithium is the lightest, smallest atomic metal with an atomic weight of 6.94 g/mol and ρ = 0.53 g/cm3. Lithium is chemically active, and it is easy to lose electrons to be oxidized to Li+. Therefore, the standard electrode potential is the most negative, -3.045 V, and the electrochemical equivalent is the smallest, 0.26 g/Ah. These characteristics of lithium determine that it is very High specific energy material. The ternary lithium battery refers to a lithium secondary battery using three kinds of transition metal oxides of nickel, cobalt and manganese as a positive electrode material. It fully integrates the good cycle performance of lithium cobaltate, the high specific capacity of lithium nickelate and the high safety and low cost of lithium manganate. It synthesizes nickel by molecular level mixing, doping, coating and surface modification. A multi-element synergistic composite lithium intercalation oxide such as cobalt manganese. It is a lithium ion rechargeable battery that has been widely studied and applied.


Life analysis of ternary lithium battery

The so-called lithium battery life means that after the battery has been used for a period of time, the capacity is attenuated to 70% of the nominal capacity (room temperature 25 ° C, standard atmospheric pressure, and battery capacity discharged at 0.2 C), and the end of life can be considered. In the industry, the cycle life is generally calculated by the number of cycles in which the lithium battery is fully charged. During the process of use, irreversible electrochemical reactions occur inside the lithium battery, resulting in a decrease in capacity, such as decomposition of the electrolyte, deactivation of the active material, collapse of the positive and negative structures, and reduction in the number of lithium ion insertion and deintercalation. . Experiments have shown that higher rate discharges result in faster attenuation of the capacity. If the discharge current is lower, the battery voltage will approach the equilibrium voltage and release more energy.

At present, the market price of ternary lithium-ion batteries is higher than that of liquid lithium-ion batteries. Compared with liquid lithium-ion batteries, it has a long life and good safety performance. It is believed that there will be a lot of room for improvement in the near future.