摘要
锂离子电池正极材料LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2)(NCM622)以其优异的能量密度及稳定性备受关注。本文以NiSO_(4)·6H_(2)O、CoSO_(4)·7H_(2)O和MnSO_(4)·H_(2)O为原料按0.6:0.2:0.2化学计量比混合,通过共沉淀法制得前驱体Ni_(0.6)Co_(0.2)Mn_(0.2)(OH)_(2)后,将碳酸锂和氢氧化锂作为熔融盐和锂源与前驱体混合,然后采用短期高温烧结与低温保温相结合的方法,制得了单晶NCM622正极材料;通过调节保温过程的温度,获得了NCM-L800、NCM-H750、NCM-H800、NCM-H8504种样品,并对其形貌、结构及电化学性能进行表征分析。结果表明:NCM-H800样品锂镍混排度最低,仅为2.37%,表现出完整的层状结构,在1C条件下循环100次容量保持率高达93.19%,表现出最佳循环稳定性;在大电流条件下,NCM-H800样品表现出了优异倍率性能。
The LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2)(NCM622)cathode material for lithium-ion batteries has attracted significant attention for its high energy density and stability.In this study,NiSO_(4)·H_(2)O,CoSO_(4)·7H_(2)O,and MnSO_(4)·H_(2)O were mixed in a stoichiometric ratio of 0.6:0.2:0.2 as raw materials.The LiNi_(0.6)Co_(0.2)Mn_(0.2)(OH)_(2) precursor was prepared by a coprecipitation method.The precursor was then combined with lithium carbonate and lithium hydroxide as molten salts and lithium sources.Single crystal NCM622 cathode material was through a two-step process involving short-term high-temperature sintering and low-temperature insulation.Four samples,NCM-L800,NCM-H750,NCM-H800,and NCM-H850,were obtained by adjusting the insulation temperature.Their morphology,crystal structure,and electrochemical properties were systematically characterized and analyzed.The results showed that the NCM-H800 sample exhibited the lowest lithium nickel miscibility(2.37%)and awell-defined layered structure.At 1C rate,thissampledemonstrated superior cycling stability with a capacity retention rate of 93.19%after 100 cycles.Additionally,under high-current conditions,NCM-H800 exhibited excellent rate capability.
作者
王崇国
胡生勇
金小容
徐兴莉
WANG Chongguo;HU Shengyong;JIN Xiaorong;XU Xingli(GanSu Vocational&Technical College of Nonferrous,Jinchang 737100,China;Jinchuan Group Nickle and Cobalt Design and Research Institute,Jinchang 737100,China)
出处
《材料科学与工艺》
北大核心
2025年第4期63-71,共9页
Materials Science and Technology
基金
甘肃省自然科学基金资助项目(22JR5RC1081)
甘肃省高等学校创新基金项目(2022B-519)
金昌市青年人才基金项目(2022RC015).
关键词
锂离子电池
NCM622正极材料
单晶结构
性能优化
合成方法
lithium ion battery
NCM622 positive electrode material
single crystal structure
performance optimization
synthetic method
