高能量密度NCM811三元正极材料的制备与改性研究  

Preparation and modification of high energy density NCM811 for lithium-ion batteries

作　　者：苏柏涛 钟盛文[1] SU Baitao;ZHONG Shengwen(Faculty of Materials Metallurgy and Chemistry,Jiangxi University of Science and Technology,Ganzhou,Jiangxi Province,341000,China)

机构地区：[1]江西理工大学材料冶金化学学部,江西赣州341000

出　　处：《电池工业》2022年第5期217-222,共6页Chinese Battery Industry

摘　　要：高镍系镍钴锰三元层状氧化物正极材料具有高比容量、低廉的价格以及环境友好性等优点,被认为最具有商业化前景的锂离子电池正极材料之一。但是,由于其表面具有较高的残碱,会影响容量的发挥、电池制浆加工性能和造成电池胀气等问题,故限制了其广泛应用。本文采用NCM811前驱体(Ni_(0.83)Co_(0.11)Mn_(0.06)(OH)_(2))和单水氢氧化锂为原料,采用掺杂Zr^(4+)的改性手段进行高温固相法制备出颗粒分散的镍钴锰酸锂。对一次烧结的镍钴锰酸锂先进行包覆ZrO_(2)和热处理,接着通过水洗和包覆H_(3)BO_(3)及再次热处理等改性,从而使镍钴锰酸锂满足低残碱量及高能量密度的要求。结果表明:当一次烧成的镍钴锰酸锂材料分别进行包覆、热处理、水洗之后接着再包覆及热处理,材料的残碱含量降低56%;克容量较高,0.1 C达212.14 mAh/g;材料的循环性能明显改善,扣电上以1 C/1 C的充放电制度进行100周循环测试,保持率达到95.42%。Nickel-rich from Ni,Co,Mn based ternary layered oxides are known as one of the most promising cathode materials for lithium-ion batteries(LIBs)owing to their high specific capacity,low price and environmental friendliness.However,its wide application is limited by the defects of high residual lithium on the surface,which seriously affects the capacity,slurry property of batteries and safety problems caused by battery gas expansion.In this paper,NCM811 precursor(Ni_(0.83)Co_(0.11)Mn_(0.06)(OH)_(2))and lithium hydroxide monohydrate were used as raw materials,and Zr^(4+) doped modification method was used to prepare particle dispersed lithium nickel cobalt manganese oxide by solid phase method.The once-sintered lithium nickel cobalt manganese oxide was modified by coating with ZrO_(2) and heat treatment,then water washing,coating with H_(3)BO_(3) and heat treatment again to meet the requirement of low residual lithium and high energy density.The results show that when the once-sintered lithium nickel cobalt manganese oxide material is subjected to coating,heat treatment and water washing,the residual lithium reduced by 56%,the lithium nickel cobalt manganese oxide material has high capacity which reaches 212.14 mAh/g.The cycle performance of material is obviously improved.The coin cell on 1 C/1 C charge-discharge system of retention rate reaches 94.42%.

关 键 词：锂电正极材料 高镍三元 NCM811 残碱 克容量 循环寿命 

分 类 号：TM911[电气工程—电力电子与电力传动]