锂单离子导电聚合物电解质的制备及界面稳定性  

Preparation and interfacial stability of single lithium-ion conductive polymer electrolytes

作　　者：王子阳 付茹 邹海凤[1,2] 陈卓 程琥[1,2] WANG Ziyang;FU Ru;ZOU Haifeng;CHEN Zhuo;CHENG Hu(School of Chemistry and Materials Science,Guizhou Normal University,Guiyang 550001,Guizhou,China;Key Laboratory of Functional Materials Chemistry of Guizhou Province,Guiyang 550001,Guizhou,China)

机构地区：[1]贵州师范大学化学与材料科学学院,贵州贵阳550001 [2]贵州省功能材料化学重点实验室,贵州贵阳550001

出　　处：《精细化工》2024年第2期358-363,共6页Fine Chemicals

基　　金：国家自然科学基金项目(22062004);贵州师范大学学术新苗基金项目(黔师新苗[2021]A08号)。

摘　　要：以苯乙烯磺酰(三氟甲基磺酰)亚胺锂(Li STFSI)、聚乙二醇甲醚甲基丙烯酸酯(PEGM)和2,2,3,3-四氟丙基甲基丙烯酸酯(TFMA)[或甲基丙烯酸八氟戊酯(OFMA)、甲基丙烯酸十二氟庚酯(DFMA)]为单体,合成了3种锂单离子导电聚合物电解质,并将其制成了隔膜,组装了CR 2025扣式电池。采用FTIR、SEM、EIS和线性扫描伏安法对隔膜进行了表征,对CR 2025扣式电池进行恒电位间歇滴定法测试。结果表明,合成的电解质膜具有较高的离子电导率(90℃,2.0×10^(-5)S/cm)、较宽的电化学稳定窗口(4.5 V)和高的锂离子迁移数(≈1)。电解质膜拥有较高的锂离子扩散系数(60℃,≥3.7×10^(-9)cm^(2)/s)。经热处理后,电解质膜与锂金属的界面稳定性得到明显提升,这归因于含氟侧链基团在聚合物电解质表面的富集。Three kinds of single lithium-ion conductive polymer electrolytes were synthesized from styrene sulfonyl(trifluoromethosulfonyl)imide lithium(LiSTFSI),polyethylene glycol methyl methacrylate(PEGM),2,2,3,3-tetrafluoropropyl methacrylate(TFMA)[or 1H,1H,5H-octafluoropentyl methacrylate(OFMA)and dodecafluoroheptyl methacrylate(DFMA)],then made into membranes,and CR 2025 button batteries were assembled accordingly.The membranes obtained were characterized by FTIR,SEM,EIS and linear sweep voltammetry,while the CR 2025 button batteries were evaluated by potentiostatic intermittent titration.The results showed that the synthesized electrolyte membranes exhibited high ionic conductivity(90℃,2.0×10^(-5) S/cm),wide electrochemical stability window(4.5 V),high lithium-ion transference number(≈1),and high lithium-ion diffusion coefficient(60℃,≥3.7×10^(-9) cm^(2)/s).The interfacial stability between the electrolyte membrane and lithium metal was significantly improved by heat treatment,which was attributed to the enrichment of fluorine-containing side chain groups on the surface of polymer electrolyte.

关 键 词：单锂离子导体 聚合物电解质 隔膜 界面稳定性 锂离子电池 功能材料 

分 类 号：TQ317[化学工程—高聚物工业] TM912[电气工程—电力电子与电力传动] TB323.2[一般工业技术—材料科学与工程]