Patent ID: 7709158

Claim:
An electrolyte for an electrochemical cell, the electrolyte comprising: a) a guanidine cation having the general formula C(NR 2 ) 3 + , wherein one or two, but not all three, of the N atoms are bonded to R radicals that are the same for each thusly substituted N atom and the third N atom is bonded to hydrogen or two of the same R radicals, and if R radicals, they are different than the R radicals bonded to the first and second N atoms, and wherein the R radicals bonded to any one N atom are an alkyl group of from 1 to 4 carbon atoms, and wherein either both of the hydrogen atoms or at least one of the hydrogen atoms on each of the R radicals bonded to one or two, but not three, of the N atoms are substituted with the same halogen selected from the group consisting of fluorine, chlorine, bromine, and iodine; b) an anion; and c) a lithium salt dissolved therein.