Lithium sulphide battery and method of producing the same

1. A chemical source of electrical energy comprising:

a positive electrode made of an electrically conductive material and substantially free of intrinsic sulfur-containing components;

a permeable separator or membrane;

a negative electrode comprising a material selected from the group consisting of an electrically conductive material and a material that is able reversibly to intercalate lithium ions, the negative electrode being substantially free of intrinsic lithium, lithium alloys and materials containing lithium ions; and

a mixture of lithium sulfide and sulfur in an aprotic electrolyte comprising at least one lithium salt in at least one solvent disposed between the electrodes;

wherein the electrodes, permeable separator and electrolyte are contained within a cell and upon application of a charge to the cell, the positive electrode incorporates sulfide ions from the mixture and the negative electrode incorporates lithium ions from the electrolyte.

2. A chemical source of electrical energy as claimed in claim 1 , wherein the positive electrode is porous.

3. A chemical source of electrical energy as claimed in claim 2 , wherein the mixture of lithium sulfide and sulfur in the aprotic electrolyte is present in pores of the porous positive electrode.

4. A chemical source of electrical energy as claimed in claim 1 , wherein the positive electrode is non-porous.

5. A chemical source of electrical energy as claimed in claim 1 , wherein the positive electrode has a surface selected from the group consisting of a developed surface and a roughened surface.

6. A chemical source of electrical energy as claimed in claim 1 , wherein the positive electrode comprises carbon.

7. A chemical source of electrical energy as claimed in claim 1 , wherein the positive electrode comprises a material selected from the group consisting of graphite, a metallic material that is resistant to corrosion in sulfide media, and a semiconductive material.

8. A chemical source of electrical energy as claimed in claim 1 , wherein the permeable separator or membrane comprises porous material.

9. A chemical source of electrical energy as claimed in claim 8 , wherein the mixture of lithium sulfide and sulfur in the aprotic electrolyte is present in pores of the porous material.

10. A chemical source of electrical energy as claimed claim 1 , wherein the mixture of lithium sulfide and sulfur is provided as a suspension, colloid, semi-solid emulsion, ointment or powder.

11. A chemical source of electrical energy as claimed in claim 10 , wherein the mixture has a solids content of 5% to 50%.

12. A chemical source of electrical energy as claimed in claim 10 , wherein the content of lithium sulfide in the mixture is from 10% to 99% by weight of the content of sulfur.

13. A chemical source of electrical energy as claimed in claim 9 , wherein the porous material is woven.

14. A chemical source of electrical energy as claimed in claim 9 , wherein the porous material is non-woven.

15. A chemical source of electrical energy as claimed in claim 1 , wherein the aprotic electrolyte comprises a solution of one or more of: lithium trifluoromethanesulfonate, lithium perchlorate, lithium trifluoromethanesulfonimide, lithium hexafluorophosphate, lithium hexafluoroarsenate, lithium tetrachloroaluminate, lithium tetraalkylammonium salt, lithium chloride, lithium bromide, and lithium iodide dissolved in one or several solvents selected from the group consisting of: dioxolane, tetrahydrofuran, dimethoxyethane, diglyme, triglyme, tetraglyme, dialkyl carbonates, sulfolane, and butyrolactone.