Title:
Boron Chemistry Based Approaches For Efficient Lithium Ion Secondary Batteries

Speaker:
Noriyoshi Matsumi (School of Materials Science, JAIST)

Abstract:
Design of organoboron electrolytes has been a fruitful method to improve ion conductive properties of various electrolyte matrices.    Molten salts covalently anchored with organoboron units were found to show significantly high lithium transference number when compared with polyether type organoboron polymers.    Further, polymerized ionic liquid bearing organoboron unit showed lithium transference number exceeding 0.8 at 30oC.   Based on these systems, organoboron ion-gel electrolytes showing both high ionic conductivity and high t+ were also developed.   In this presentation, design of a variety of well-defined organoboron electrolytes and their structure-property relationship will be reviewed.   Alkylborane type electrolytes generally showed higher lithium transference number due to stronger Lewis acidity of alkylborane unit.   Anion trapping effect worked more efficiently in IL based media than that was observed in PEO based media.   Design of novel low molecular weight organoboron solid electrolyte and their unusual ion conductive behavior will also be presented. Further, we are recently also working on surface modification of graphite by electropolymerization of organoboron monomer aiming at improving cyclability.   Monomer synthesis, polymerization behavior, surface characterization and charge-discharge behaviors will be discussed in detail.