Conductivity enhancement of polyacrylonitrile-based electrolytes by addition of cascade nitrile compounds

• Published in: Journal of power sources Vol. 90; no. 1; pp. 33 - 38
• Main Authors: Tsutsumi, Hiromori, Matsuo, Akiko, Takase, Kimio, Doi, Shizuka, Hisanaga, Atsushi, Onimura, Kenjiro, Oishi, Tsutomu
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Lausanne Elsevier B.V 2000; Elsevier Sequoia
• Subjects: Applied sciences; Cascade molecule; Conductive enhancer; Direct energy conversion and energy accumulation; Electrical engineering. Electrical power engineering; Electrical power engineering; Electrochemical conversion: primary and secondary batteries, fuel cells; Exact sciences and technology; Plasticizer; Polyacrylonitrile; Polyethylene oxide; Solid polymer electrolyte; Conductive enhancer; Polyacrylonitrile; Plasticizer; Polyethylene oxide; Cascade molecule; Solid polymer electrolyte; Ethylene oxide polymer; Polyethylene; Nitrile; Battery; Ionic conductivity; Polymer solid electrolyte; Secondary cell; Lithium ion
• ISSN: 0378-7753; 1873-2755
• DOI: 10.1016/S0378-7753(00)00444-4

A cascade nitrile compound ([CH 2N(CH 2CH 2CN) 2] 2, ED4CN) made by addition of acrylonitrile to alkyldiamine (1,2-diaminoethane), has been used as a plasticizer for solid polymer electrolytes. The ionic conductivity of a polymer electrolyte using this type of plasticizer in polyethylene oxide (PEO)– and polyacrylonitrile (PAN)–LiClO 4 complex was measured. Addition of ED4CN to PEO-based electrolytes did not enhance the conductivity of them. However, interaction between ED4CN and lithium ions in the complex was confirmed by infrared spectroscopy. The peak assigned to the stretching vibration of nitrile group in ED4CN shifted to high-energy side. The shift indicated that the nitrile groups interacted with the lithium ions in the PEO-based electrolytes. Conductivity enhancement was observed in the PAN-based electrolytes containing ED4CN. Conductivity of the electrolyte containing ED4CN was about 10 or 23 times larger than that of the electrolyte without ED4CN. Addition of ED4CN to a PAN–LiClO 4 electrolyte decreases the glass transition temperature of the complexes. Conductivity enhancement of the PAN-based electrolyte with ED4CN containing lithium salt in high concentration was also confirmed. Other low molecular weight additives, tetraethylsulfamide (TESA) and a cascade nitrile compound, ([CH 2CH 2N(CH 2CH 2CN) 2] 2, TE4CN) were also used and their possibility for a conducting enhancer of PAN-based electrolytes was tested. TESA was effective; however, TE4CN was inactive for a conductance enhancer of the PAN-based electrolytes.