ELECTROLYTES WITH LOW CATIONIC MOBILITY ACTIVATION ENERGIES

An electrolyte includes a composite salt mixture formed from a halogen-free closo-borate salt and a halogenated closo-borate salt. The halogen-free closo-borate salt includes a first cation selected from Li, Na, Mg, or Ca, and a closo-borate anion with the structure [BHR], [CB()HR], [CBHR], [CBHR], or [CBHR], and a second cation selected from Li, Na, Mg, or Ca,and a halogenated closo-borate anion with the structure [BHRX], [CB()HRX], [CBHRX], [CBHRX], or [CBHRX]. The parameter y is an integer within a range of 6 to 12, z is an integer within a range of 0 to y, t is an integer within a range of 0 to (y−1), z+i is an integer within a range of 0 to y, t+j is an integer within a range of 0 to y−1, R is a linear, branched-chain, or cyclic C1-C18 alkyl or fluoroalkyl group, and X is F, Cl, Br, and/or I.