文献类型：期刊文献

中文题名：电解液溶剂组成对钠离子电池性能的影响及其机制研究

英文题名：Study on influence and mechanism of electrolyte solvent composition on sodium ion batteries

作者：赵丽丽[1];刘振兴[2];陈庆威[1];陈万桂[1];潘伟童[1];许建良[1];陈雪莉[1];王辅臣[1]

机构：[1]华东理工大学资源与环境工程学院,上海200237;[2]华陆工程科技有限责任公司,陕西西安710065

年份：2025

卷号：53

期号：5

起止页码：1

中文期刊名：化学工程

外文期刊名：Chemical Engineering(China)

收录：;北大核心:【北大核心2023】；

语种：中文

中文关键词：钠离子电池;电解液;溶剂组成;电化学性能;固态电解质界面膜

外文关键词：sodium ion battery;electrolyte;solvent composition;electrochemical performance;solid electrolyte interface film

摘要：溶剂是钠离子电池电解液的重要组成部分,在电解液系统中质量分数达80%-85%,深入了解溶剂组成对提高钠离子电池电化学性能、循环寿命和安全性具有重要意义。以六氟磷酸钠(NaPF6)为电解液溶质,揭示了EC(碳酸乙烯酯)、DMC(碳酸二甲酯)、EMC(碳酸甲乙酯)等典型溶剂组成对钠离子电池性能的影响及其机制。实验结果表明:EC/DMC/EMC三元电解液体系在Na-HC(硬碳)半电池中的综合性能最优,其中EC/DMC/EMC(体积比1∶1∶1)在30 mA/g的电流密度条件下,其可逆比容量为304.2 mA·h/g,首周库仑效率88.85%;循环80圈后比容量达298.8 mA·h/g,容量保持率97.42%。EC/DMC/EMC(体积比1∶2∶2)电解液在高倍率5C充放电后,返回0.2C倍率时的比容量达到246.3 mA·h/g,相比之下二元电解液体系DMC/EMC(体积比1∶1)中仅为92.6 mA·h/g。CV、XPS和TEM表征显示,EC/DMC/EMC(体积比1∶2∶2)溶剂组成下形成了一层以NaF为主的均匀的SEI(固态电解质界面膜),使得该电池具有优越的电化学性能。
Solvent is an important part of sodium ion battery electrolyte,which accounts for 80%-85%of mass in the electrolyte system.The soluent composition plays an important role in improving the electrochemical performance,cycle life and safety of sodium ion batteries.Using sodium hexafluorophosphate(NaPF 6)as the electrolyte solute,the effects and mechanisms of typical solvent compositions such as EC(ethylene carbonate),DMC(dimethyl carbonate)and EMC(methyl ethyl carbonate)on the performance of sodium ion batteries were revealed.The results show that the electrolyte composed of EC/DMC/EMC has the best comprehensive performance in Na-HC(hard carbon)half battery.At a current density of 30 mA/g,the reversible specific capacity in the electrolyte composed of EC/DMC/EMC(volume ratio 1:1:1)is 304.2 mA·h/g,and the first coulomb efficiency is 88.85%.After 80 cycles,the specific capacity reaches 298.8 mA·h/g,and the capacity retention rate is 97.42%.After charging and discharging at a high magnification of 5C,the specific capacity in the electrolyte composed of EC/DMC/EMC(volume ratio 1:2:2)returns at 0.2C is 246.3 mA·h/g.However,in the electrolyte composed of DMC/EMC(volume ratio 1:1)the specific capacity is only 92.6 mA·h/g。Further analysis by CV,XPS and TEM showes that a more uniform SEI(solid electrolyte interface film)dominated by NaF is formed under the optimal solvent composition of EC/DMC/EMC.So that the battery has superior cycle performance and rate performance.