Effect of Heating-Cooling Cycles on Electrical Behavior of Polymer Electrolytes

Frequency dependent conductivity of amorphous polymericsolid electrolyte containing LiN(SO2CF3)2 (LiTFSI) or LiBF4 wasstudied. Successive heating and cooling cycles showed changeable conductivity behavior, which was due to chemistry change in the lithiumsalts. Both salts showed a tendency of decreasing conductivity inthe second cooling process. The decrease in conductivity behavior forsamples containing LiBF4 was much higher if compared with thosecontaining LiTFSI. Effect of heat on polymer network itself was not considered in this investigation.