超高镍LiNi_(0.91)Co_(0.06)Al_(0.03)O_(2)@Ca_(3)(PO_(4))_(2)正极材料的储锂稳定性的提升机制  

Enhanced Lithium Storage Stability Mechanism of Ultra-high Nickel LiNi_(0.91)Co_(0.06)Al_(0.03)O_(2)@Ca_(3)(PO_(4))_(2) Cathode Materials

作　　者：朱河圳 王选朋 韩康 杨晨 万睿哲 吴黎明 麦立强[1,3] ZHU Hezhen;WANG Xuanpeng;HAN Kang;YANG Chen;WAN Ruizhe;WU Liming;MAI Liqiang(School of Material Science and Engineering,Wuhan University of Technology,Wuhan 430070,China;School of Science,Wuhan University of Technology,Wuhan 430070,China;Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong Laboratory,Foshan 528200,China)

机构地区：[1]武汉理工大学材料科学与工程学院,武汉430700 [2]武汉理工大学理学院,武汉430700 [3]先进能源科学与技术广东省实验室佛山分中心(佛山仙湖实验室),佛山528200

出　　处：《无机材料学报》2022年第9期1030-1036,I0012-I0014,共10页Journal of Inorganic Materials

基　　金：国家重点研发计划(2020YFA0715000);国家自然科学基金(51832004,21905218);武汉理工大学自主创新研究基金项目(WUT:2021-LX-B1-04)。

摘　　要：超高镍正极材料具有高比能、高电压和低成本等特点,在新一代锂离子电池中备受关注,但在电池的长循环过程中会出现微裂纹、机械粉化和不可逆相变,导致差的循环性能。本研究采用简便的湿化学法制备了一系列Ca_(3)(PO_(4))_(2)包覆的超高镍LiNi_(0.91)Co_(0.06)Al_(0.03)O_(2)材料(NCA@n CP)。其中,NCA@1CP在1C (1C=200 m A/g)、2.7~4.3 V下可获得204.8 m Ah/g的放电比容量,100圈循环后容量保持率为91.5%,甚至在2C的倍率下循环300圈后仍保留153.4 mAh/g的放电比容量。表征结果证实该包覆层可抑制材料的Li/Ni混排、不可逆相变和机械粉化,从而大幅提升了循环稳定性。本研究表明Ca_(3)(PO_(4))_(2)包覆策略在提升超高镍正极材料储锂稳定性方面具有较大的应用潜力。Ultra-high nickel material as a new lithium-ion battery cathode has attracted much attention due to its high specific capacity,high voltage and low cost.However,the generated microcracks,mechanical pulverization and irreversible phase transformation during cycling,result in poor cycling stability.Herein,a series of Ca_(3)(PO_(4))_(2)-coated ultra-high nickel LiNi_(0.91)Co_(0.06)Al_(0.03)O_(2) materials with different thicknesses (NCA@n CP) were prepared through a facile wet-chemistry strategy.Among them,NCA@1CP manifested specific discharge capacity of 204.8 m Ah/g under 2.7–4.3 V at 1C (1C=200 mA/g),with a capacity retention rate of 91.5%after 100 cycles.Even after 300 cycles at 2C,the specific discharge capacity retained 153.4 m Ah/g.Material characterization results further confirm that the coating shell inhibits the Li/Ni mixing,irreversible phase transformation and mechanical pulverization of the NCA@1CP,greatly improving the cycling stability.This work shows that the Ca_(3)(PO_(4))_(2) coating strategy has great application potential in improving the lithium storage stability of ultra-high nickel cathode materials.

关 键 词：锂离子电池 超高镍正极 Ca_(3)(PO_(4))_(2) 表面包覆 

分 类 号：TQ174[化学工程—陶瓷工业]