锂离子电池过充特性的研究

以尖晶石锰酸锂作锂离子电池正极材料,研究其过充电特性及影响因素.结果表明,电池1C过充特性和正极活性物质的量有关,与负极活性物质的量无关.充电倍率是影响电池过充特性的关键因素,低倍率过充时,结束电池过充的主要原因是内部电解液分解殆尽;高倍率过充时,因电池内部产生的热量增加,散热相对滞后,导致电池内部温度升高隔膜熔断从而截断回路结束过充.

A Study of Overcharge Characteristic of Lithium-ion Cells

The overcharge characteristics and effect factors of lithium-ion cells containing LiMn2O4 cathodes were studied in detail. Overcharge testing of Lithium-ion cells with a systematic variation in the cell balance demonstrated that the overcharge characteristics of Lithium-ion cells was affected by the amount of cathode in the cells, which is independent of the amount of anode material. The rate of charge was found to be an important parameter, as electrolyte complete decomposition at low charge rates caused the end of overcharge testing, while high charge rates accelerated the rate of heat generation in the cells and the cell temperature increased as a result of insufficient heat dissipation. The cell temperature rise led to the separator shut down and testing end.