Electrochemical Characteristics of Single Ion conductor based on Blend of PMMA Ionomer and PEG Ionomer

Abstract

In this study, a new single ion conductor based on blend of P(MMA-co-LiMA) and PEGLi ionomer was prepared and its electrochemical characteristics were investigated. The ionic conductivity of the solvent-free single ion conductor based on P(MMA-co-LiMA)/PEGLi blend was investigated with the content of PEGLi. Two type of liquid electrolyte, EC/PC and DMA, were introduced as a plasticizer and the ionic conductivities were examined. The ionic conductivity of the polymer electrolyte plasticized with the DMA was higher than that of the polymer electrolyte plasticized with EC/PC. In the polymer electrolyte containing DMA, the mobility of charge carrier found to be higher and the pathway to be less tortuous than those of the polymer electrolyte containing EC/PC. The ionic conductivities increased with liquid electrolyte content. This was explained by increase in charge carrier number and mobility of charge carrier. The ionic conductivities of plasticized P(MMA-co-LiMA)/PEGLi blend with DMA were investigated with the content of PEGLi ionomer. As the content of PEGLi increases, the mobility of charge carrier increases and the tortuosity of pathway decreases. Thus the ionic conductivity of the plasticized blend increases with the increase of the PEGLi content. Interfacial resistance of Li/blended polymer electrolyte/Li cell was investigated with the content of PEGLi. The interfacial property was enhanced with the increase of the PEGLi content due to the increase of the film flexibility. It was found that electrochemical stability of the single ion conductor is more stable than that of the bi-ionic conductor. The prepared single ion conductor based on 38mol% P(MMA-co-LiMA)/PEGLi blend containing DMA was stable up to 6V.