Amorphous matrices prepared from branched polymers for lithium tonic conduction

Lithium ionic conductivities of amorphous oxyethylene matrices prepared from several branched polymers are overviewed in this article. The relationship between the ionic conductivity and structural characteristics of high-molecular mass branched poly(oxyethylene)s is focused. These branched polymers were synthesized by coordination ionic copolymerization based on the concept of molecular design of elastomers. Oxyethylene segments possessed a good compatibility for lithium salts and an adequate mobility for lithium ionic conduction. Additionally, the oxyethylene side segments decreased the crystallinity and glass transition temperature of high-molecular mass branched poly(oxyethylene)s. These effects of branched segments gave rise to their ionic conductivities in order of 10(-4)S/cm at 30 degreesC. The high-molecular mass branched poly(oxyethylene)s showed a good processability and a rubber elasticity at room temperature without crosslinking. Therefore, the amorphous high-molecular mass branched poly(oxyethylene)s will be useful as one component of thin and light solid electrolytes for high-density rechargeable lithium batteries.