CYCLOALIPHATIC EPOXIDE-BASED PHOTOCURED GELLED ELECTROLYTES FOR SECONDARY LITHIUM BATTERY APPLICATIONS - ELECTROCHEMICAL KINETIC-STUDIES

Cycloaliphatic epoxide-based thin gelled films prepared by ultraviolet photocuring were characterized electrochemically. Mixtures of ethylen e carbonate and various organic liquids in different volume ratios wer e used as solvents. General composition of the electrolyte was cycloal iphatic epoxide (being sold under the trade name ENVIBAR by Union Carb ide) 10 to 28 weight percent (w/o), polyethylene oxide (200,000 Mw) 4 to 10 w/o, LiAsF6, 6 to 22 w/o, and mixed solvents (of different volum e ratios) 80 to 40 w/o. Thin gelled films were formed on lithium (Li) electrodes and subjected to electrochemical studies. Typical values of bulk electrolyte specific conductivity and interfacial resistance obt ained from ac impedance and dc measurements at room temperatures are 2 x 10(-3) S cm-1 and 3.2 OMEGA cm2, respectively Charge/discharge char acteristics of the cells of the Li/electrolyte/TiS2 type were evaluate d. Cathode utilization was only 33% of the total capacity.