ELECTROCHEMICAL PROPERTIES OF LITHIUM SALT-POLY(ETHYLENE OXIDE)ETHYLENE CARBONATE POLYMER ELECTROLYTE AND DISCHARGE CHARACTERISTICS OF LI MNO2/

Lithium salt-poly(ethylene oxide) polymer (PEG) electrolyte was prepar ed by solvent casting method. Ethylene carbonate (EC) was added to imp rove the ionic conductivity of the polymer electrolytes. The ionic con ductivity of polymer electrolytes increased from 1.8 x 10(-7) S cm(-1) to 2.7 x 10(-5) S cm-L at 30 degrees C when the weight ratio of EC an d PEO increased from 0 to 0.8. The activation energy of ionic conducti vity obtained from log sigma vs. 1/T plot was 26.1 kJ mol(-1) when the EC/PEO weight ratio and [O]/[Li+] molar ratio were 0.8 and 25, respec tively. The cyclic voltammetry results indicated that increasing the t emperature resulted in the decrease of the peak potential difference o f stripping of Li and deposition of Li+ (Delta E(p)). The discharge ch aracteristic of lithium-manganese cell was significantly affected by t he polymer electrolyte complexes, discharge temperature and current de nsity.