Lithium battery self-discharge

Lithium battery self-discharge is a battery voltage drop in the circuit can be replaced, in ternary lithium, lithium cobalt oxide, manganese oxide material electrode, lithium battery self-discharge phenomenon was inevitable.
Lithium-ion battery self-discharge capacity loss according to whether or not reversible is divided into two: the capacity loss reversible refers to the second battery capacity can be restored; irreversible capacity loss, capacity cannot be recovered. The factors affecting the level of self-discharge: cathode and cell preparation process, nature and concentration of the electrolyte, the battery storage temperature and storage time, among them, the temperature dependence is relatively large.
Lithium-ion batteries self-discharge, loss of capacity and much of it can be recovered, following a case of lithium manganese oxide to analyze the reasons behind this phenomenon.
Speaking from the mechanism, fully charged lithium ion battery self-discharge is due to the decomposition of the electrolyte response and caused the initial interrelation reaction of lithium, it is not reversible, which is reversible.
Furthermore, lithium in the anode and cathode of the embed and removal of block was able to recover, because the electrode at the same rate of self-discharge, which implies a capacity balancing mechanism, but long after discharge, two electrodes of capacity balance will be broken, and then charge deposition of carbon anode for lithium in danger, causing volume cannot be recovered.
Self-discharge can be represented by lithium-ion batteries self-discharge rate, however, the self-discharge rate is uncertain. In mechanism, main is by electrolytic quality solvent of oxidation rate control of, solvent oxidation main occurred in carbon black surface, low surface area of carbon black can control since discharge rate, for manganese acid lithium battery,, reduced activity material of surface area, and delay solvent in set fluid of oxidation is important of, above is in lithium battery preparation process in the caused different since discharge rate of roots.
Lithium battery self-discharges as well as the influence of external factors. One is the effect of storage time, as mentioned above, the longer, the capacity of the li ion battery between anode and cathode balance will be gradually broken and deepening, and decomposition of the electrolyte will also accumulate some irreversible capacity loss. Thus, longer storage time, self-discharge rate will increase.
Lithium-ion battery's self-discharge rate is negligible relative to other types of batteries, which is determined by the structure of lithium-ion batteries. Therefore, for the lithium-ion battery self-discharge capacity loss of expression is generally one month calculated. Typically, lithium-ion batteries at room temperature of the month self discharge rate of 3%, but if you do not pay attention to the environment is likely to accelerate, as in 55 high temperature self discharge rate of 10%, it was room temperature 3 times, Although discharge caused part capacity can be restored, but the self-discharge rate is staggering under high temperature, long-term in inappropriate temperatures, will have much impact on ultimate lithium battery life. 
Contact:
Person: Tim.lee
Company: Dongguan Large Electronics Co., Ltd
Add: Block A, Gaosheng Technology Zone, Nancheng District, Dongguan City, Guangdong Province, CN
Tel: 86-769-23182621
Email: Tim.lee@largepower.cn

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