基于Mn3+浓度和形貌控制的高性能LiNi0.5Mn1.5O4正极材料  

High-Performance LiNi0.5Mn1.5O4 Cathode Materials Based on Mn3+ Concentration and Morphology Control

作　　者：罗英[1] 王勇[1] 郭满毅 薛志民 刘雯[1] 晏莉琴[1] 解晶莹[1] 闵凡奇 LUO Ying;WANG Yong;GUO Manyi;XUE Zhimin;LIU Wen;YAN Liqin;XIE Jingying;MIN Fanqi(State Key Laboratory of Space Power Sources Technology,Shanghai Institute of Space Power Sources,Shanghai 200245,China;Shanghai Power and Energy Storage Battery System Engineering Technology Co.,Ltd.,Shanghai 200241,China;School of Materials Science and Engineering,Northwestern Polytechnical University,Xi’an 710072,Shaanxi,China;School of Environmental and Chemical Engineering,Yanshan University,Qinhuangdao 066004,Hebei,China)

机构地区：[1]上海空间电源研究所空间电源技术国家重点实验室,上海200245 [2]上海动力储能电池系统工程技术有限公司,上海200241 [3]西北工业大学材料学院,陕西西安710072 [4]燕山大学环境与化学工程学院,河北秦皇岛066004

出　　处：《上海航天（中英文）》2020年第2期46-53,共8页Aerospace Shanghai（Chinese&English）

基　　金：国家自然科学青年基金资助项目(21805186);国家重点研发计划资助项目(2018YFB0104402)。

摘　　要：为了改善高电压镍锰酸锂(LiNi0.5Mn1.5O4)材料的电化学性能,提出利用退火热处理过程调控Mn3+含量和材料形貌来制备LiNi0.5Mn1.5O4正极材料。LiNi0.5Mn1.5O4材料的电性能是材料结构、形貌等多因素影响的结果。退火热处理有助于Mn3+氧化成Mn4+,实现Mn3+含量调控。退火后材料的空间结构由Fd3m向P4332转变,且具有微米级多面体形貌,有效提高了循环稳定性和放电平台。研究表明:700℃退火保温15 h合成的材料在20 C下具有118 mAh·g-1放电比容量,循环100次容量保持率提高到92.8%。因此,通过优化Mn3+含量、控制材料形貌可以实现高性能LiNi0.5Mn1.5O4材料制备。In order to improve the electrochemical properties of high-voltage LiNi0.5Mn1.5O4 materials,it is proposed to prepare the LiNi0.5Mn1.5O4 cathode materials by adjusting the Mn3+ concentration and material morphology through annealing. The electrical properties of LiNi0.5Mn1.5O4 are influenced by many factors such as the structure and morphology of the material. Annealing heat treatment is helpful for the oxidation of Mn3+ to Mn4+,so that the control of Mn3+ concentration can be realized. After annealing,the spatial structure of the material is transformed from Fd3m to P4332,and has a micro-scale polyhedron morphology,which effectively improves the cycling stability and dischargevoltage platform. The results show that the material annealed at 700 ℃ for 15 h has a specific discharge capacity of 118 mAh·g-1 at 20 C,and the capacity retention rate is increased to 92.8% after 100 cycles. Therefore,high-performance LiNi0.5Mn1.5O4 materials can be prepared by optimizing the Mn3+ concentration and controlling the material morphology.

关 键 词：锂离子电池 LiNi0.5Mn1.5O4材料 高电压 Mn3+含量 形貌 

分 类 号：TQ152[化学工程—电化学工业]