基于高速球磨法的磷酸锰锂正极材料制备及Fe掺杂性能研究  

Preparation and Fe doping properties of lithium manganese phosphate cathode materials based on high-speed ball milling method

作　　者：信凤艳 魏安潞 李欣然 邹杰[1] 常龙娇 XIN Fengyan;WEI Anlu;LI Xinran;ZOU Jie;CHANG Longjiao(Key Laboratory of Liaoning Silicon Material Engineering Technology Research Center,Bohai University,Jinzhou Liaoning 121013,China)

机构地区：[1]渤海大学辽宁省硅材料工程技术研究中心重点实验室,辽宁锦州121013

出　　处：《化工矿物与加工》2024年第11期45-52,共8页Industrial Minerals & Processing

基　　金：国家自然科学基金项目(51804035);河北省电介质与电解质功能材料重点实验室资助项目(HKDEFM202301)。

摘　　要：锂离子电池具有较高的能量密度及倍率性能,已成为新能源汽车的首选电池应用体系。其中LiMnPO_(4)正极材料具有安全性能好、成本低等优点,是锂离子电池中的主流材料之一,但由于其导电性较差、电化学性能不理想,制约了其市场应用。本文基于高速球磨法制备了LiMnPO_(4)正极材料,考察了球磨时间和焙烧温度对材料电化学性能的影响,结果表明:当球磨时间为20 h时,在0.1 C倍率下LiMnPO_(4)正极材料的首次放电比容量可达162 mA·h/g,在1 C倍率下经过100周循环后的容量保持率可达94.3%;当焙烧温度为750℃时,LiMnPO_(4)正极材料经过100周不同倍率循环后,在2 C倍率下放电比容量仍可达132.3 mA·h/g。采用Fe掺杂制得LiMn_(1-x)Fe_(x)PO_(4)正极材料,在最佳掺杂量为30%的条件下制得的LiMn_(0.7)Fe_(0.3)PO_(4)正极材料首次放电比容量达165 mA·h/g,经过100周循环后的容量保持率达98%。Lithium-ion batteries have become the preferred battery application system for new energy vehicles due to their high energy density and rate performance.Among them,LiMnPO_(4) cathode material has the advantages of high safety performance and low cost,and is one of the mainstream materials in lithium ion batteries.However,due to its poor conductivity and unsatisfactory electrochemical performance,its market application is restricted.In this paper,LiMnPO_(4) cathode material was prepared by high-speed ball milling method.The effects of ball milling time and calcination temperature on the electrochemical properties of the material were investigated.The results show that when the ball milling time is 20 h,the first discharge specific capacity of LiMnPO_(4) cathode material can reach 162 mA·h/g at 0.1 C rate,and the capacity retention rate can reach 94.3% after 100 cycles at 1 C rate.When the calcination tempe-rature is 750 ℃,the discharge capacity of LiMnPO_(4) cathode material can still reach 132.3 mA·h/g at a high rate of 2 C after 100 cycles at different rates.The LiMn_(1-x)Fe_xPO_(4) cathode material is prepared by Fe doping.The first discharge specific capacity of LiMn_(0.7) Fe_(0.3)PO_(4) cathode material prepared under the optimum doping amount of 30% is 165 mA·h/g,and the capacity retention rate is 98% after 100 cycles.

关 键 词：锂离子电池 正极材料 磷酸锰锂 高速球磨法 电化学性能 高温焙烧 掺杂 循环试验 

分 类 号：TQ131.11[化学工程—无机化工]