LITHIUM SUPERACID SALTS FOR SECONDARY LITHIUM BATTERIES

Three newly prepared lithium superacid double dagger salts of the type CnF2n+1SO3Li (where n is 4, 8 and 10) and CF3SO3Li and (CF3SO2)(2)NLi were used as salts in polyethylene oxide (PEG) electrolytes. Our conductivity data shows that among the salts investigated PEO electrolytes containing (CF3SO2)(2) NLi gave the highest conductivity followed by C4F9SO3Li and C3F17SO3Li. PEO electrolytes containing C10F21SO3Li and CF3SO3Li showed a lower conductivity at room temperature than the rest. Experimental Li-TiS2 polymer cells containing either PEO-C4F9SO3Li or PEO-(CF(3)S0(2))(2)NLi as electrolyte were fabricated and tested for cycle life performance. No significant loss in capacity was observed even after 50 to 100 cycles.