Lithium-ion conductivity of the Nafion membrane swollen in organic solvents

• Published in: Russian journal of electrochemistry Vol. 51; no. 10; pp. 986 - 990
• Main Authors: Sanginov, E. A., Evshchik, E. Yu, Kayumov, R. R., Dobrovol’skii, Yu. A.
• Format: Journal Article
• Language: English
• Published: Moscow Pleiades Publishing 01-10-2015
• Subjects: Chemistry; Chemistry and Materials Science; Electrochemistry; Physical Chemistry; Short Communications; aprotic solvents; lithium-ion conductivity; dimethyl sulfoxide; ion-conducting membranes; Nafion; activation energy; swelling of membranes
• ISSN: 1023-1935; 1608-3342
• DOI: 10.1134/S1023193515100122

The lithium-ion conductivity of the lithium form of the commercial perfluorinated membrane Nafion-115 was studied in a series of aprotic solvents in a wide temperature range. The highest ion conductivity was obtained for the sample kept in N,N-dimethyl formamide (DMF); its use in lithium-ion batteries, however, is restricted by its low electrochemical stability. Mixed solvents based on dimethyl sulfoxide (DMSO) with propylene carbonate (PC) and 1,2-dimethoxyethane (DME) additions were optimum solvents for ion transport. The Nafion membrane in the lithium form kept in a mixed solvent DMSO: PC: DME = 1: 1: 2 was characterized by high ion conductivity at room temperature (2.0 mS/cm) and the absence of phase transitions in the temperature range from–40 to +60°C. The activation energy of conductivity of the samples kept in DMF, DMSO, and mixed solvents based on DMSO above the transition temperature was 15–20 kJ/mol.