双掺杂策略助力单晶LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2)材料  

Double doping strategy assisted single crystal LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2) material

作　　者：陈彦恒 张志超[1,2] CHEN Yanheng;ZHANG Zhichao(Henan Intelligent Safety Engineering Research Center for Rail Transit,Zhengzhou 450018,China;Zhengzhou Railway Vocational Technical College,Zhengzhou 450052,China)

机构地区：[1]河南省轨道交通智能安全工程技术研究中心,河南郑州450018 [2]郑州铁路职业技术学院,河南郑州450052

出　　处：《兵器材料科学与工程》2023年第3期59-64,共6页Ordnance Material Science and Engineering

基　　金：河南省科技攻关项目(212102310457)。

摘　　要：锂离子电池中,由超高镍LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2)组成的层状正极材料是实现高能量密度的关键。高镍含量正极材料具有高能量密度、长寿命、低成本优势,商业化需求量很大。高压运行是提高锂离子电池能量密度的有效途径。然而,高压循环下不可逆的容量衰减使正极材料难获得高效的容量保持率。以Al_(2)O_(3)和TiO_(2)为掺杂物质,经高温固相烧结合成Al/Ti共掺杂的单晶正极材料LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2)。用X射线衍射、扫描电子显微镜和透射电镜对Al/Ti共掺杂的调节机制进行表征和分析。结果表明:Al/Ti共掺杂可有效抑制不可逆相变,促进Li^(+)的传输,稳定材料的层状结构。这项工作揭示共掺杂的关键作用,说明Al/Ti掺杂如何调控正极材料的晶体结构,为开发高性能层状正极提供新思路。In Li‐ion batteries,the layered cathode material composed of ultra‐high nickel LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2is) the key to achieve high energy density.High nickel content cathode materials have the advantages of high energy density,long life and low cost,so there is a great demand for commercialization of ultra‐high nickel layered oxide cathode active materials.High voltage operation is an effective way to improve the energy density of lithium‐ion batteries.However,the irreversible capacity attenuation under high pressure cycling makes it difficult to obtain efficient capacity retention of cathode materials.In this work,Al/Ti co‐doped single crystal cathode material LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2was) synthesized by high temperature solid phase sintering using Al_(2)O_(3) and TiO_(2) as doping substances.The regulatory mechanism of Al/Ti co‐doping was characterized and analyzed by X‐ray diffraction,scanning electron microscope and transmission electron microscopy.The results show that Al/Ti co‐doping can effectively inhibit the irreversible phase transition,promote the Li~+ transport,and stabilize the layered structure of the material.This work reveals the key role of co‐doping and illustrates how Al/Ti doping regulates the crystal structure of positive materials,thus providing new ideas for the development of high performance layered positive electrodes.

关 键 词：锂离子电池 单晶LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2) Al/Ti共掺杂 层状结构 

分 类 号：TG113[金属学及工艺—物理冶金] TM[金属学及工艺—金属学]