Realizing high initial Coulombic efficiency in manganese-based layered oxide cathodes for sodium-ion batteries via P2/O'3 biphasic structure optimization

作     者：Bo Peng Zi-Hao Zhou Ping Xuan Jie Xu Lian-Bo Ma Bo Peng;Zi-Hao Zhou;Ping Xuan;Jie Xu;Lian-Bo Ma

作者机构：School of Materials Science and EngineeringAnhui University ofTechnologyMa'anshan 243002China Anhui Product Quality Supervision&Inspection Research InstituteHefei 230051China 

出 版 物：《Rare Metals》 (稀有金属（英文版）)

年 卷 期：2024年第43卷第5期

页      面：2093-2102页

核心收录：

学科分类：0808[工学-电气工程] 0806[工学-冶金工程] 08[工学] 0805[工学-材料科学与工程（可授工学、理学学位）] 

基　　金：supported by the Natural Science Research Project of Anhui Province Education Department(No.2022AH050334) the Scientific Research Foundation of Anhui University of Technology for Talent Introduction(No.DT2200001211) the New Energy Electric Vehicles High-Voltage Components Inspection and Testing Public Service Platform 

主　　题：Sodium-ion batteries Cathode materials Mn-based layered oxides P2/0'3 composites 

摘      要：Mn-based layered oxides are among the most promising cathode materials for sodium-ion batteries owing to the advantages of abundance,environmenta friendliness,low cost and high specific capacity.P2 and O 3 are two representative structures of Mn-based layered ***,the P2 structure containing insufficien Na generally exhibits low initial charge capacity,while O 3structure with sufficient Na delivers high initial charge capacity but poor cycle *** study prepared a multitude of Na_(x)MnO_(2)(x=0.7,0.8,0.9)cathode materials with varying P2/O 3 ratios and further investigated their electrochemical *** optimized Na_(0.8)MnO_(2) comprising 69.9 wt%O 3 and 30.1 wt%P2 phase,exhibited relatively balanced specific capacity,Coulombic efficiency and cycle ***,it achieved a high specific capacity of 128.9 mAh·g^(-1) with an initia Coulombic efficiency of 98.2%in half-cell configuration The Na_(0.8)MnO_(2)//hard carbon full cell also achieved a high specific capacity of 126.7 mAh·g^(-1) with an initia Coulombic efficiency of 98.9%.Moreover,the capacity fading mechanism was revealed by combining in-situ and ex-situ X-ray *** findings of this study provide theoretical guidance for further modification design of Mnbased layered cathodes.