单晶NCM811正极材料的制备以及电化学性能的研究  

Preparation of single crystal NCM811 cathode materials and study on their electrochemical properties

作　　者：吴允龙 江晓雪 郭旗 李翠芹[1,2] WU Yun-long;JIANG Xiao-xue;GUO Qi;LI Cui-qin(School of Chemistry and Chemical Engineering,Guizhou University,Guiyang 550025,China;Guizhou Provincial Collaborative Innovation Center for Efficient Utilization of Phosphorus and Fluorine Resources,Guiyang 550025,China)

机构地区：[1]贵州大学化学与化工学院,贵州贵阳550025 [2]贵州省磷氟资源高效利用协同创新中心,贵州贵阳550025

出　　处：《现代化工》2025年第1期149-155,共7页Modern Chemical Industry

基　　金：含氟电解质及电解液的关键技术开发与示范(黔科合战略找矿[2022]ZD006号);贵州省教育厅自然科学基金项目(黔教技[2022]001号)。

摘　　要：富镍层状正极材料(LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2),NCM811)因具有极高的充放电比容量被广泛关注,但是其在循环过程中面临着严重的结构退化以及界面不稳定的问题。采用多步煅烧法协同球磨法成功制备了单晶NCM811正极材料(SC-NCM),并对其电化学性能进行了测试。结果表明,以SC-NCM为正极、锂片为负极组装的半电池首圈库伦效率为85.4%,在1 C循环200次后拥有86.2%的容量保持率;以石墨为负极、SC-NCM为正极组装的全电池在相同的测试条件下达到了94.1%的容量保持率。通过对比传统NCM811(PC-NCM)与SC-NCM在循环期间的差异,分析得出对高镍三元正极材料长循环稳定性最大的影响因素;同时提出了多步煅烧法协同球磨法合成SC-NCM正极材料的新策略,以加速NCM811商业化。Nickel-rich layered cathode materials,specifically LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811),have garnered significant attention due to their high charge/discharge specific capacity.However,these materials are prone to structural degradation and interfacial instability during cycling.To address these issues,single crystal NCM811(SC-NCM)materials are successfully synthesized through using a multistep calcination method in conjunction with ball milling method,and their electrochemical performance is tested.It is found that the half-cell,which is assembled with SC-NCM as the cathode and lithium wafers as anode,exhibits a first-cycle Coulombic efficiency of 85.4%.Additionally,it maintains a capacity retention rate of 86.2% after 200 cycles at 1 C.The full-cell,which is assembled with graphite as anode and SCNCM as cathode,achieves a 94.1% of capacity retention rate under the same conditions.The differences between conventional NCM811(PC-NCM)and SC-NCM during cycling are compared to analyze the most influential factors on the long cycle stability of high nickel ternary cathode materials.In this study,a new strategy for the synthesis of SC-NCM cathode materials by multi-step calcination method combining with ball milling method is proposed to accelerate the commercialization of NCM811.

关 键 词：单晶NCM811 循环稳定性 SC-NCM||石墨全电池 多步煅烧法 

分 类 号：TM912[电气工程—电力电子与电力传动]