Electrochemical properties of composite polymer electrolyte applied to rechargeable lithium polymer battery

摘要

High-molecular-weight comb-shaped polyethers, poly(ethylene oxide-co-2-(2-methoxyethoxy) ethyl glycidyl ether-co-allyl glycidyl ether) (P(EO/EM/AGE)) and poly(ethylene oxide-co-2-(2-methoxyethoxy)ethyl glycidyl ether) (P(EO/EM)), were synthesized and used for the preparation of the all solid polymer electrolyte and the composite polymer electrolyte combined with a plasticizer Star-EO-OMe, pentaerythritol tetrakis(2-methoxyethyl ether), which shows low vapor pressure, respectively. Some electrochemical properties of the polymer electrolytes and performances of the cell consisting of lithium/polymer electroly te/LiCodh were studied. The addition of Star-EO-OMe to polymer electrolyte brought about a large increase in ionic conductivity. The composite electrolyte containing 50 wt. percent of Star-EO-OMe complexed with LiTFSI, lithium bis(trifluoromethylsulfonyl)imide, exhibited high ionic conductivity in the order of 10~(-4) S cm~(-1) at 10 deg C and approximately 10(-5) S cm~(-1) at -20 deg C. The cell performance was also improved by the addition of Star-EO-OMe.