Effect of microphase separation on the limiting current density in hybrid organic-inorganic copolymer electrolytes

Hybrid organic-inorganic block copolymer electrolytes are of interest to enable batteries containing lithium metal anodes. The conductive is a standard polymer electrolyte poly(ethylene oxide) and the mechanically rigid an inorganic poly(acryloisobutyl polyhedral oligomeric silsesquioxane) polymer. In this paper, we compare silsesquioxane)-b-poly(ethylene oxide)-b-poly(acryloisobutyl (POSS-PEO-POSS) triblock oxide)-b- (PEO-POSS) diblock mixed with bis(trifluoromethanesulfonyl)imide salt. We have experimentally measured limiting current density in symmetric cells hybrid at 90 °C. were polarized large range applied density. exhibited clear plateau cell potential all densities below At low density, also potential. currents approaching underdamped profile. did not reach above both systems. fully characterized using electrochemical methods determine ionic conductivity, cation fraction, salt diffusion coefficient, open circuit voltage as function concentration. Cell concentration functions position various calculated Newman's concentrated solution theory. theoretical was be which depleted cathode. see quantitative agreement between experimental measurements predictions for has ordered structure concentrations, while lower than prediction electrolyte, exhibits disordered morphology high concentrations.