Lithium sulphide battery and method of producing the same

Abstract

A chemical source of electrical energy may include a positive electrode (cathode) made of an electrically conductive material, a mixture of lithium sulphide and sulphur, a permeable separator or membrane, and a negative electrode (anode) made of an electrically conductive material or a material that is able reversibly to intercalate lithium ions, wherein an aprotic electrolyte comprising at least one lithium salt in at least one solvent is provided between the electrodes.

1 . A chemical source of electrical energy comprising:
 a positive electrode made of an electrically conductive material,   a mixture of lithium sulphide and sulphur,   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, and   an aprotic electrolyte comprising at least one lithium salt in at least one solvent disposed between the electrodes.   
     
     
         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 1 , wherein the positive electrode is non-porous. 
     
     
         4 . 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. 
     
     
         5 . A chemical source of electrical energy as claimed in  claim 1 , wherein the positive electrode has a smooth 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 sulphide 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  claim 1 , wherein the mixture of lithium sulphide and sulphur is provided as a suspension, colloid, semi-solid emulsion, ointment or powder. 
     
     
         10 . A chemical source of electrical energy as claimed in  claim 9 , wherein the mixture has a solids content of 5% to 50%. 
     
     
         11 . A chemical source of electrical energy as claimed in  claim 9 , wherein the content of lithium sulphide in the mixture is from 10% to 99% by weight of the content of sulphur. 
     
     
         12 . A chemical source of electrical energy as claimed in  claim 8 , wherein the porous material is woven. 
     
     
         13 . A chemical source of electrical energy as claimed in  claim 8 , wherein the porous material is non-woven. 
     
     
         14 . A chemical source of electrical energy as claimed in  claim 1 , wherein the aprotic electrolyte comprises a solution of one or more of: lithium trifluoromethanesulphonate, lithium perchlorate, lithium trifluoromethanesulphonimide, 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. 
     
     
         15 . A method of manufacturing a chemical source of electrical energy, the method comprising:
 providing a cathode;   providing a mixture of lithium sulphide and sulphur in an aprotic electrolyte comprising at least one lithium salt in at least one solvent;   applying a coating of the mixture to the cathode;   applying a permeable separator or membrane over the coated cathode;   applying a coating of an aprotic electrolyte comprising at least one lithium salt in at least one solvent over the permeable separator or membrane;   providing an anode on the coating of aprotic electrolyte, the anode being made of an electrically conductive material or a material that is able reversibly to intercalate lithium ions; and   providing terminal connections for the anode and cathode and hermetically sealing the structure obtained.   
     
     
         16 . A method according to  claim 15 , wherein the cathode is porous. 
     
     
         17 . A method according to  claim 15 , wherein the cathode has a smooth surface. 
     
     
         18 . A method according to  claim 15 , wherein the aprotic electrolyte contains a mixture of lithium sulphide and sulphur. 
     
     
         19 . A method according to  claim 15 , wherein the aprotic electrolyte does not contain a mixture of lithium sulphide and sulphur. 
     
     
         20 . A method according to  claim 15 , wherein the structure is folded or otherwise shaped prior to sealing.