NOVELTY - Electrolyte solution comprises a salt, a solvent and a metal compound (I).    USE - The electrolyte solution is useful in batteries containing a high voltage cathode or a low voltage cathode, and in batteries operated at high temperatures, where the batteries is useful to supply power for consumer electronics, portable electronics, hybrid vehicles, electrical vehicles, power tools, power grid, military applications, and aerospace applications.    ADVANTAGE - The electrolyte solution provides a number of desirable characteristics when implemented within batteries, such as high stability during battery cycling to high voltages at or above 4.2 V or 4.3 V, high specific capacity upon charge or discharge, high coulombic efficiency, excellent retention of specific capacity and energy density over several cycles of charging and discharging, high rate capability, reduced electrolyte decomposition, reduced resistance and its build-up during cycling, and improved calendar life.    DETAILED DESCRIPTION - Electrolyte solution comprises a salt, a solvent and a metal compound of formula (A(M+)B1y(N1-)) (I).    A = metal ion, preferably transition metal ion, rare earth element ion or main group element ion;    M+ = oxidation number of the metal ion;    B1 = silicon containing anion of formula (R2-Si(R1)(R3)-X) (II) or (R2-Si(R1)(R3)-X1-Y1), preferably trimethylsilyl containing anion, where B1 further comprises a nitrogen containing group or an oxygen containing group;    N1- = negative charge of the anion;    y = number of anions;    R1-R3 = 1-20C alkyl, 1-20C alkenyl, 1-20C alkynyl or 5-20C aryl (all optionally substituted);    X = oxygen containing group;    X1 = nitrogen containing group; and    Y1 = hydride, halo, hydroxy, thio, alkyl, alkenyl, alkynyl, aryl, iminyl, alkoxy, alkenoxy, alkynoxy, aryloxy, carboxy, alkylcarbonyloxy, alkenylcarbonyloxy, alkynylcarbonyloxy, arylcarbonyloxy, alkylthio, alkenylthio, alkynylthio, arylthio, CN, N-substituted amino, alkylcarbonylamino, N-substituted alkylcarbonylamino, alkenylcarbonylamino, N-substituted alkenyl carbonylamino, alkynylcarbonyl amino, N-substituted alkynylcarbonylamino, arylcarbonylamino, N-substituted arylcarbonylamino, boron-containing groups, aluminum-containing groups, silicon-containing groups (preferred), phosphorus-containing groups or sulfur-containing groups.    DESCRIPTION OF DRAWING(S) - The figure shows a schematic view of lithium-ion battery.    Battery (100)    Anode (102)    High voltage electrolyte (104)    Cathode (106)    Separator. (108)