Composition and energy storage device

An article comprising:

• a cathode;
• wherein the cathode comprises:
• at least one electroactive metal, wherein the electroactive metal is at least one selected from the group consisting of titanium, vanadium, niobium, molybdenum, nickel, iron, cobalt, chromium, manganese, silver, antimony, cadmium, tin, lead and zinc;
• a first alkali metal halide;
• an electrolyte salt comprising a reaction product of a second alkali metal halide and a metal halide, wherein the electrolyte salt has a melting point of less than about 300 degrees Centigrade;
• and
• a metal chlorosulfide compound having a formula (I) M1M2p+1SnCl4+3p−2n wherein “M1” is a metal selected from group IA of the periodic table, “M2” is a metal selected from group IIIA of the periodic table, “p” is 0 or 1, and “n” is equal to or greater than 0.5.

An energy storage device comprising:

• (a) a first compartment comprising an alkali metal;
• (b) a second compartment comprising a cathode composition, the cathode composition comprising:
• at least one electroactive metal, wherein the electroactive metal is at least one selected from the group consisting of titanium, vanadium, niobium, molybdenum, nickel, iron, cobalt, chromium, manganese, silver, antimony, cadmium, tin, lead and zinc;
• a first alkali metal halide;
• an electrolyte salt comprising a reaction product of a second alkali metal halide and a metal halide, wherein the electrolyte salt has a melting point of less than about 300 degrees Centigrade;
• and
• a metal chlorosulfide compound having a formula (I) M1M2p+1SnCl4+3p−2n wherein “M1” is a metal selected from group IA of the periodic table, “M2” is a metal selected from group IIIA of the periodic table, “p” is 0 or 1, and “n” is equal to or greater than 0.5;
• and
• (c) a solid separator capable of transporting alkali metal ions between the first and the second compartments.

A method for forming an energy storage device comprising:

• providing a housing having an interior surface defining a volume;
• disposing a separator inside the housing, wherein the separator has a first surface that defines at least a portion of a first compartment, and a second surface that defines a second compartment;
• wherein the first compartment is in ionic communication with the second compartment through the separator;
• disposing a cathode composition in the second compartment, wherein the cathode composition comprises:
• at least one electroactive metal, wherein the electroactive metal is at least one selected from the group consisting of titanium, vanadium, niobium, molybdenum, nickel, iron, cobalt, chromium, manganese, silver, antimony, cadmium, tin, lead and zinc;
• a first alkali metal halide;
• an electrolyte salt comprising a reaction product of a second alkali metal halide and a metal halide, wherein the electrolyte salt has a melting point of less than about 300 degrees Celsius;
• and
• a metal chlorosulfide compound having a formula (I) M1M2p+1SnCl4+3p−2n wherein “M1” is a metal selected from group IA of the periodic table, “M2” is a metal selected from group IIIA of the periodic table, “p” is 0 or 1, and “n” is equal to or greater than 0.5;
• wherein a molten solution of the metal chlorosulfide compound in the electrolyte salt is impregnated in a mixture comprising the at least one electroactive metal and the alkali metal halide.