表面包覆对LiNi_(0.5)Mn_(1.5)O_(4)电极材料循环性能改善研究

Study on Improvement of Cycling Performance of LiNi_(0.5)Mn_(1.5)O_(4) Electrode Material by Surface Coating

能量密度是判断锂离子电池技术用于混合动力汽车(HEV)和插电式混合动力汽车(PHEV)应用的关键参数,因此增加锂离子电池中的插层化合物的容量有利于提高锂电池的能量密度。采用氧化物涂层来抑制电解质与LiNi_(0.5)Mn_(1.5)O_(4)正极材料的氧化副反应。由于纳米Al_(2)O_(3)不活泼且不能插入或提取锂离子,Al_(2)O_(3)导致LiNi_(0.5)Mn_(1.5)O_(4)电极容量降低。在1 C下经过40次充放电循环后,涂覆有5%纳米Al_(2)O_(3)的LiNi_(0.5)Mn_(1.5)O_(4)具有72.94%容量保持率,结果表明纳米Al_(2)O_(3)涂层对于改善LiNi_(0.5)Mn_(1.5)O_(4)材料的循环性能没有显著影响。

Energy density is a key parameter for the successful adoption of lithium-ion battery technology for hybrid electric vehicle(HEV)and plug-in hybrid electric vehicle(PHEV)applications.Therefore,increasing the capacity of the intercalation compound in the lithium ion battery is beneficial to improve the lithium battery energy density.An oxide coating was used to suppress the side oxidation reaction between the electrolyte and the LiNi_(0.5)Mn_(1.5)O_(4) cathode material.Because nano-Al_(2)O_(3) was inactive and cannot insert or extract lithium ions,Al_(2)O_(3) coating reduced the capacity of LiNi_(0.5)Mn_(1.5)O_(4) coating.After 40 charge-discharge cycles at 1 C,LiNi_(0.5)Mn_(1.5)O_(4) coated with 5%nano-Al_(2)O_(3) had a capacity retention rate of 72.94%.The experimental results showed that the nano-Al_(2)O_(3) coating had no significant effect on improving the cycle performance of LiNi_(0.5)Mn_(1.5)O_(4) material.