高能量密度LiNi_(0.9)Co_(0.06)Mn_(0.04)O_(2)正极材料的制备与改性研究

Research on Preparation and Modification of High-energy-density LiNi_(0.9)Co_(0.06)Mn_(0.04)O_(2) Cathode Material

高镍系镍钴锰三元正极材料因其高能量密度在动力电池上得到广泛应用,但结构稳定性较差。开发高能量密度兼顾良好稳定性能的正极材料成为当前研究的热点。本文以前驱体Ni_(0.9)Co_(0.06)Mn_(0.04)(OH)_(2)和锂源LiOH·H_(2)O为原料在纯氧气氛下烧结制得多晶LiNi_(0.9)Co_(0.06)Mn_(0.04)O_(2)三元正极材料,并对一次烧结样品以ZrO_(2)进行一次包覆、H_(3)BO_(3)二次包覆等改性研究,从而使镍钴锰三元材料满足高能量密度和良好稳定的要求。纽扣式半电池测试结果表明:当一次烧结镍钴锰酸锂材料分别包覆ZrO_(2),接着再包覆H_(3)BO_(3),材料的0.1C克容量达216.32 mAh/g;材料的循环性能明显改善,1C/1C的倍率充放电下进行100次循环测试,容量保持率达94.45%。

Nickel-rich from Ni,Co,Mn based ternary cathode materials are widely used in power batteries due to their high energy density,but they have the disadvantage of poor structural stability.The development of cathode materials with high energy density and good stability has become a research hotspot.In this paper,polycrystalline LiNi_(0.9)Co_(0.06)Mn_(0.04)O_(2) ternary cathode material was sintered in a pure oxygen atmosphere using the precursor Ni_(0.9)Co_(0.06)Mn_(0.04)(OH)_(2) and lithium source LiOH·H_(2)O as raw materials.Then,modification studies were conducted on the primary sintered samples through primary coating with ZrO_(2),and secondary coating with H3BO3,so that the nickel-cobalt-manganese ternary material could meet the requirements of high energy density and good stability.The button-type half-cell test results showed that when the primary sintered lithium nickel cobalt manganese oxide material was coated with ZrO_(2),followed by coating with H_(3)BO_(3),the 0.1C gram capacity of the material reached 216.32 mAh/g,the cycle performance of the material was significantly improved,and the capacity retention rate reached 94.45%after 100 cycles of charge-discharge tests at a 1C/1C rate.