锰基钠离子电池正极材料设计及电化学性能研究  

Study on cathode material design and electrochemical properties of manganese-based sodium ion battery

作　　者：刘德新 马腾跃 安金玲 刘进荣[1] 何伟艳[1] LIU Dexin;MA Tengyue;AN Jinling;LIU Jinrong;HE Weiyan(College of Chemical Engineering,Inner Mongolia University of Technology,Hohhot 010051,China)

机构地区：[1]内蒙古工业大学化工学院,内蒙古呼和浩特010051

出　　处：《无机盐工业》2024年第3期51-55,共5页Inorganic Chemicals Industry

基　　金：内蒙古自治区自然科学基金项目(2023LHMS02002);自治区高校基本科研业务费项目(ZTY2023030)。

摘　　要：钠离子电池因环境友好、储量丰富等优势,成为锂离子电池的后继者,在储能材料方面有很大的应用潜力。针对钠离子电池锰基正极材料存在结构不稳定、循环稳定性差等问题,采用溶胶-凝胶法制备Na_(0.7)Fe_(x)Mn(1-x)O_(2)(0<x<1)锰基正极材料,考察铁锰物质的量比对Na_(0.7)Fe_(x)Mn(1-x)O_(2)材料微观结构、电化学性能的影响。结果表明:铁的掺杂稳定了材料P2相晶型且增加了钠层间距;合成的两种材料Na_(0.7)Fe_(0.2)Mn_(0.8)O_(2)和Na_(0.7)Fe0.35Mn0.65O_(2)在电压范围为2~4 V、放电倍率为0.5C的条件下,首次充/放电比容量分别为88.54、63.73 mA·h/g和74.02、49.01 mA·h/g,循环100次后充/放电比容量分别为51.94、51.36 mA·h/g和52.15、51.59 mA·h/g,循环效率分别为58.01%和69.7%,表现出良好的容量保持和循环性能;在倍率方面,两种材料经过2C大电流充电后,重新循环到0.5C倍率时两种材料的充/放电比容量仍可达113.82、110.25 mA·h/g和51.75、51.11 mA·h/g,两种材料都表现了较好的循环倍率性能,其中Na_(0.7)Fe_(0.2)Mn_(0.8)O_(2)材料的性能表现得更加优异。Sodium ion batteries have become the successor of lithium ion batteries due to their advantages of environmental friendliness and abundant reserves,and have great application potential in energy storage materials.In view of the problems of unstable structure and poor cycle stability of manganesebased cathode materials for sodium ion batteries,Na_(0.7)Fe_(x)Mn(1-x)O_(2)(0<x<1)manganesebased cathode materials were prepared by sol-gel method.The effects of n(Fe)/n(Mn)molar ratio on the microstructure and electrochemical properties of Na_(0.7)Fe_(x)Mn(1-x)O_(2) materials were investigated.The results showed that the doping of iron stabilized the P2 phase crystal form of the material and increased the sodium layer spacing.The P2-phase layered cathode materials of Na_(0.7)Fe_(0.2)Mn_(0.8)O_(2) and Na_(0.7)Fe_(0.35)Mn_(0.65)O_(2) were synthesized.The synthesized two materials of Na_(0.7)Fe_(0.2)Mn_(0.8)O_(2) and Na_(0.7)Fe_(0.35)Mn_(0.65)O_(2) had charge/discharge specific capacities of 88.54,63.73 mA·h/g and 74.02,49.01 mA·h/g in the first cycle.After 100 cycles,the charge/discharge specific capacities were 51.94,51.36 mA·h/g and 52.15,51.59 mA·h/g,respectively,and the cycle efficiencies were 58.01%and 69.7%,respectively,showing good capacity retention and cycle performance.In terms of rate,the charge and discharge specific capacity of the two materials could still reach 113.82,110.25 mA·h/g and 51.75,51.11 mA·h/g when the two materials were charged at 2C high current and recycled to 0.5C rate.Both materials showed good cycle rate performance.In general,the performance of Na_(0.7)Fe_(0.2)Mn_(0.8)O_(2) was more excellent.

关 键 词：锰基 正极材料 铁掺杂 P2相 比容量 

分 类 号：TQ137.12[化学工程—无机化工]