LiMn_(2)O_(4)正极材料的制备及其电化学性能  

Preparation and Electrochemical Properties of LiMn_(2) O_(4) Cathode Material

作　　者：曾帅波 陈烨 唐俊雄 潘惜园 关宏坚 徐伟 ZENG Shuaibo;CHEN Ye;TANG Junxiong;PAN Xiyuan;GUAN Hongjian;XU Wei(College of Automotive and Transportation Engineering,Guangdong Technical Normal University,Guangzhou 510630,China)

机构地区：[1]广东技术师范大学汽车与交通工程学院,广东广州510630

出　　处：《合成化学》2024年第6期508-516,共9页Chinese Journal of Synthetic Chemistry

基　　金：广东省基础与应用基础研究基金资助项目(2022A1515110102);广州市科技计划项目(202201011098);广东省教指委本科在线开放课程课题项目(2022ZXKC271);广东省科技创新战略专项资金(大学生科技创新培育)资助项目(pdjh2023b0310);教育部高等教育司产学研协同育人项目(202102211092);广东技术师范大学校级科研人才专项项目(2021SDKYA105);广东技术师范大学研究生教育创新计划资助项目(2021991040354)。

摘　　要：相比钴酸锂等传统的正极材料,锰酸锂具有资源丰富、成本低、无污染、安全性好及倍率性能好等优点,是理想的动力电池正极材料。利用高温固相合成法,通过改变合成温度制备LiMn_(2)O_(4)正极材料,并对LiMn_(2)O_(4)正极材料调制的浆料采用不同涂覆厚度以达到改善锰酸锂电池的电化学性能。利用扫描电镜(SEM)和透射电镜(TEM)对制备的电极材料进行形貌分析;利用热重差热测试(TGA/DSC)对电极反应物和制备电极成分进行分析;利用蓝电电池测试系统和电化学工作站对电极电化学性能进行分析。研究表明:制备的LiMn_(2)O_(4)正极材料为纳米结构且部分颗粒发生了团聚现象;TGA/DSC数据表明制备的正极材料在800℃依然没有分解;对比电化学测试数据,当合成温度达800℃时,样品材料具有良好的结晶度和尖晶八面体形貌,其综合电化学性能远优于其他合成温度下(600℃, 700℃和900℃)的样品材料,在0.2 C下最高的首次比容量高达135.8 mAh·g^(-1),库伦效率为94.15%,且涂覆200μm厚度的电极比100μm的电极片表现出更好的电化学性能。Compared with traditional cathode materials such as lithium cobalt oxide, lithium manganate has the advantages of abundant resources, low cost, no pollution, good safety, good rate performance, etc., and is an ideal cathode material for power batteries. The LiMn_(2) O_(4) cathode material was prepared by high temperature solid sintering method by changing the sintering temperature, and the LiMn_(2) O_(4) cathode material was prepared with different coating thickness to improve the electrochemical performance of lithium manganate battery. In this paper, scanning electron microscope(SEM) and transmission electron microscope(TEM) were used to analyze the morphology of the electrode materials. The electrode reactants and components of the prepared electrode were analyzed by TGA/DSC. The electrochemical performance of the electrodes was analyzed by using the battery test system and electrochemical workstation. The results show that when the LiMn_(2) O_(4) cathode material is nano-structured and some of the particles were agglomerated;TGA/DSC data showed that the cathode was not decomposed at 800 ℃. Compared with the electrochemical test data, when the sintering temperature reaches 800 ℃, the sample material has good crystallinity and the morphology of apical octahedron, and its comprehensive electrochemical performance is much better than that of other groups of sample materials at the sintering temperature(600 ℃, 700 ℃ and 900 ℃). At 0.2 C, the highest initial specific capacity was 135.8 mAh·g^(-1) , the Coulomb efficiency was 94.15%, and the electrode coated with 200 μm thickness showed better electrochemical performance than that of 100 μm.

关 键 词：锂离子电池 锰酸锂材料 合成温度 涂覆厚度 电化学性能 制备工艺 

分 类 号：TM911[电气工程—电力电子与电力传动]