铝、钴元素共掺杂对尖晶石型锰酸锂高温循环性能的研究  

A Study on High Temperature Cyclic Performance of Spinel Lithium Manganese Oxide Co-doped with Al and Co

作　　者：陈美林 杨茂峰 李春流 詹海青 万维华 黎明 闫冠杰 CHEN Meilin;YANG Maofeng;LI Chunliu;ZHAN Haiqing;WAN Weihua;LI Ming;YAN Guanjie(Chongzuo Branch,South Manganese Group Limited,Chongzuo,Guangxi 532200,China;South Manganese Group Limited,Nanning,Guangxi 530029,China)

机构地区：[1]南方锰业集团有限责任公司崇左分公司,广西崇左532200 [2]南方锰业集团有限责任公司,广西南宁530029

出　　处：《中国锰业》2021年第3期43-47,共5页China Manganese Industry

基　　金：广西科技重大专项(桂科AA17204063)。

摘　　要：采用高温固相法在相同的条件下制备了LiMn_(2)O_(4)及不同Al、Co量掺杂的LiAl_(x)Co_(y)Mn_(2-x-y)O_(4)(x=0.06,y=0.01)锰酸锂正极材料。使用XRD、SEM对材料的结构与微观形貌进行表征,通过恒电流充放电测试、循环伏安(CV)和交流阻抗(EIS)研究了两种材料的电化学性能差异。XRD和SEM表征结果表明:Al、Co都很好地掺杂进入尖晶石结构中,并没有杂相产生,元素掺杂并没有改变材料的形貌;在60℃高温条件下,LiMn_(2)O_(4)循环100次后保持率为71.85%,而铝、钴元素共掺杂制备的LiAl_(0.06)Co_(0.01)Mn_(1.93)O_(4)循环100次后保持率为80.56%,具有更加良好的高温循环性能。交流阻抗测试表明LiAl_(0.06)Co_(0.01)Mn_(1.93)O_(4)比LiMn_(2)O_(4)有较大的SEI膜阻抗。LiMn_(2)O_(4) and LiAl_(x)Co_(y)Mn_(2-x-y)O_(4)(x=0.06,y=0.01)with different Al and Co contents doping lithium manganate cathode materials were prepared by high temperature state method under the same conditions.The structure and morphology of the materials were characterized by XRD and SEM.The electrochemical properties were studied by galvanostatic charge/discharge testing,cyclic voltammetry(CV)and A.C.impedance(EIS).XRD and SEM characterization results show that both materials were spinel structure.No impurity phase is produced.Electrochemical performance tests show that the Li-Al_(0.06)Co_(0.01)Mn_(1.93)O_(4)Co-doped with Al and Co kept better electrochemical performance than LiMn_(2)O_(4) under the high temperature of 60℃after 100 cycles at 1C rate.In the same condition,the capacity retention of the two materials was 80.56%and 71.85%.AC impedance test shows that LiAl_(0.06)Co_(0.01)Mn_(1.93)O_(4) had a large SEI film impedance than LiMn_(2)O_(4).

关 键 词：铝、钴元素共掺杂 高温固相法 锰酸锂 高温循环性能 

分 类 号：TM912[电气工程—电力电子与电力传动] TQ131.11[化学工程—无机化工]