Abstract: There is disclosed a method of making a surface-modified alkali metal material for electrochemical use, the method comprising bringing a barrier agent into frictional contact with an alkali metal substrate to form a tribochemical barrier layer on the substrate. Also disclosed is a surface-modified alkali metal material for electrochemical use, the material comprising an alkali metal substrate bearing a tribochemical barrier layer.

Abstract: A method of forming a lithium coating on a substrate, the method comprising: melting a solid lithium target to form a molten lithium target; agitating the molten lithium target; vaporising at least part of the agitated molten lithium target to form a vaporised material; and condensing the vaporised material on a substrate to form a lithium coating.

Abstract: A permeable composite material for making an electrode for an electrochemical cell, the composite material comprising: a support defining pores; and alkali metal deposited on the support within a plurality of said pores. An electrode comprising the composite material is also described, as are methods of making the material and cells and assemblies comprising the electrode.

Abstract: A metal foil electrode comprising i) a reinforcement layer formed from a porous substrate, and ii) first and second layers of metal foil formed comprising lithium and/or sodium, wherein the reinforcement layer is disposed between the first and second metal foil layers and bonded (preferably pressure bonded) together to form a composite structure having a thickness of 100 microns or less.

Abstract: A method of forming a lithium coating on a substrate, the method comprising: melting a solid lithium target to form a molten lithium target; agitating the molten lithium target; vaporising at least part of the agitated molten lithium target to form a vaporised material; and condensing the vaporised material on a substrate to form a lithium coating.

Abstract: A permeable composite material for making an electrode for an electrochemical cell, the composite material comprising: a support defining pores; and alkali metal deposited on the support within a plurality of said pores. An electrode comprising the composite material is also described, as are methods of making the material and cells and assemblies comprising the electrode.

Abstract: Solid composite electrodes with electrode active layers that include an electrode active material, an optional electron conductive material, an optional binder and other optional additives for batteries which are not fuel cells are provided. The solid composite electrodes are formed by the deposition of an electrode composition (slurry) onto a current collector in one or many layers. The electrode structure may be characterized by a porosity of the electrode composition layer that decreases in a direction from the back side of the layer (close to the current collector) towards the outer side of the layer. The electrode structures can be used in for example chemical sources of electric energy such as primary (non-rechargeable) as well as secondary (rechargeable) batteries.

Abstract: There are disclosed electrolytes comprising solutions of lithium salts with large anions in polar aprotic solvents with a particular concentration of background salts. The concentration of the background salts is selected to be equal or close to the concentration of a saturated solution of these salts in the aprotic solvents used. The electrolytes disclosed can be used in chemical sources of electric energy such as secondary (rechargeable) cells and batteries comprising sulphur-based positive active materials. The use of such electrolytes increases cycling efficiency and cycle life of the cells and batteries.

Abstract: The invention provides for a method of discharging a chemical source of electric energy in two stages. The chemical source of electric energy comprises a positive electrode (cathode) including sulphur or sulphur-based organic compounds, sulphur-based polymeric compounds or sulphur-based inorganic compounds as a depolarizer, a negative electrode (anode) made of metallic lithium or lithium-containing alloys, and an electrolyte comprising a solution of at least one salt in at least one aprotic solvent. The method comprises the steps of configuring the chemical source of electric energy to generate soluble polysulphides in the electrolyte during a first stage of a two stage discharge process, and selecting the quantity of sulphur in the depolarizer and the volume of electrolyte in a way that after the first stage discharge of the cathode, the concentration of the soluble polysulphides in the electrolyte is at least seventy percent (70%) of a saturation concentration of the polysulphides in the electrolyte.

Abstract: A metal foil electrode comprising i) a reinforcement layer formed from a porous substrate, and ii) first and second layers of metal foil formed comprising lithium and/or sodium, wherein the reinforcement layer is disposed between the first and second metal foil layers and bonded (preferably pressure bonded) together to form a composite structure having a thickness of 100 microns or less.

Abstract: The invention provides for a method of discharging a chemical source of electric energy in two stages. The chemical source of electric energy comprises a positive electrode (cathode) including sulphur or sulphur-based organic compounds, sulphur-based polymeric compounds or sulphur-based inorganic compounds as a depolarizer, a negative electrode (anode) made of metallic lithium or lithium-containing alloys, and an electrolyte comprising a solution of at least one salt in at least one aprotic solvent. The method comprises the steps of configuring the chemical source of electric energy to generate soluble polysulphides in the electrolyte during a first stage of a two stage discharge process, and selecting the quantity of sulphur in the depolariser and the volume of electrolyte in a way that after the first stage discharge of the cathode, the concentration of the soluble polysulphides in the electrolyte is at least seventy percent (70%) of a saturation concentration of the polysulphides in the electrolyte.

Abstract: An electrolyte for a lithium-sulphur battery, the electrolyte comprising a solution of at least one electrolyte salt in at least two aprotic solvents. The components of the solution may be selected so that the solution is eutectic or close to eutectic. Also disclosed is a lithium-sulphur battery including such an electrolyte. By using a eutectic mixture, the performance of the electrolyte and the battery at low temperatures is much improved.

Abstract: The invention provides for a method of discharging a chemical source of electric energy in two stages. The chemical source of electric energy comprises a positive electrode (cathode) including sulphur or sulphur-based organic compounds, sulphur-based polymeric compounds or sulphur-based inorganic compounds as a depolarizer, a negative electrode (anode) made of metallic lithium or lithium-containing alloys, and an electrolyte comprising a solution of at least one salt in at least one aprotic solvent. The method comprises the steps of configuring the chemical source of electric energy to generate soluble polysulphides in the electrolyte during a first stage of a two stage discharge process, and selecting the quantity of sulphur in the depolariser and the volume of electrolyte in a way that after the first stage discharge of the cathode, the concentration of the soluble polysulphides in the electrolyte is at least seventy percent (70%) of a saturation concentration of the polysulphides in the electrolyte.

Abstract: Solid composite electrodes with electrode active layers that include an electrode active material, an optional electron conductive material, an optional binder and other optional additives for batteries which are not fuel cells are provided. The solid composite electrodes are formed by the deposition of an electrode composition (slurry) onto a current collector in one or many layers. The electrode structure may be characterized by a porosity of the electrode composition layer that decreases in a direction from the back side of the layer (close to the current collector) towards the outer side of the layer. The electrode structures can be used in for example chemical sources of electric energy such as primary (non-rechargeable) as well as secondary (rechargeable) batteries.

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.

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.

Abstract: A multi-electrode lithium-sulphur cell or battery including for example a negative electrode made of metal lithium, lithium alloys or lithium-absorbing materials; at least first and second distinct positive electrodes or groups of positive electrodes; and an electrolyte that is a solution of one or several salts in one or several solvents disposed between the negative and positive electrodes. The first positive electrode or group of positive electrodes is configured for charging, and the second positive electrode or group of positive electrodes is configured for discharging. The cell or battery has a high specific energy. Other embodiments of the present invention may include other structures and properties.

Abstract: There are disclosed electrolytes comprising solutions of lithium salts with large anions in polar aprotic solvents with a particular concentration of background salts. The concentration of the background salts is selected to be equal or close to the concentration of a saturated solution of these salts in the aprotic solvents used. The electrolytes disclosed can be used in chemical sources of electric energy such as secondary (rechargeable) cells and batteries comprising sulphur-based positive active materials. The use of such electrolytes increases cycling efficiency and cycle life of the cells and batteries.

Abstract: The invention discloses a method of increasing the cycle life of rechargeable battery with a negative electrode (anode) made of lithium or lithium-containing alloys and electrolyte/salt solution which comprises one or more non-aqueous organic solvents and one or more lithium salts, the method comprising adding to the electrolyte/salt solution a lithium dendrite scavenging additive in an amount sufficient that a rate of lithium dendrite formation is equal to or lower than a rate of lithium dissolution occurring due to interaction with the dendrite scavenging additive dissolved in the electrolyte.

Abstract: The invention provides for a method of discharging a chemical source of electric energy in two stages. The chemical source of electric energy comprises a positive electrode (cathode) including sulphur or sulphur-based organic compounds, sulphur-based polymeric compounds or sulphur-based inorganic compounds as a depolarizer, a negative electrode (anode) made of metallic lithium or lithium-containing alloys, and an electrolyte comprising a solution of at least one salt in at least one aprotic solvent. The method comprises the steps of configuring the chemical source of electric energy to generate soluble polysulphides in the electrolyte during a first stage of a two stage discharge process, and selecting the quantity of sulphur in the depolariser and the volume of electrolyte in a way that after the first stage discharge of the cathode, the concentration of the soluble polysulphides in the electrolyte is at least seventy percent (70%) of a saturation concentration of the polysulphides in the electrolyte.