A low-temperature electrolyte for lithium and lithium-ion batteries

An electrolyte consisting of 1 M solution of lithium hexafluorophosphate in 1:1:1 ethylene carbonate(EC)-dimethyl carbonate(DMC)-ethyl methyl carbonate(EMC) is proposed for low temperature applications of lithium and lithium-ion cells. The new electrolyte has good conductivity and electrochemical stability. Lithium and lithium-ion cells using the new electrolyte were found to be operable at temperatures down to -40 degrees C. The paper also reports on the electrochemical stability of aluminum metal, which is used as a substrate for the positive electrodes in lithium-ion cells, in the new electrolyte. (C) 2000 Elsevier Science S.A. All rights reserved.