Abstract: An electrode for lithium ion recharged battery cell includes current collectors, a cathode layer, a separator and a cohesive anode mass. The cohesive anode mass includes silicon as an active material and a polymeric binder. The polymeric binder is a homo-polymer or copolymer of one or more monomers selected from the group consisting of acrylic acid, 3-butenoic acid, 2-methacrylic acid, 2-pentenoic acid, 2,3-dimethylacrylic acid, 3,3-dymethylacrylic acid, trans-butenedioc acid, cis-butenedioc acid and itaconic acid and optionally an alkali metal salt thereof. The silicon can include 20 to 100% of the active material in the cohesive mass. The binder is mixed with the silicon to form the cohesive mass that adheres to the current collector and maintains the cohesive mass in electrical contact with the current collector.

Abstract: Disclosed are a composite electrode material for a rechargeable battery; a method of making a composite electrode material; an electrode including the composite electrode material; cells including such electrodes; and devices including the cells. A composite electrode material for a rechargeable battery cell includes an electroactive material; and a polymeric binder including pendant carboxyl groups. The electroactive material includes one or more components selected from the group including an electroactive metal, an electroactive semi-metal, an electroactive ceramic material, an electroactive metalloid, an electroactive semi-conductor, an electroactive alloy of a metal, an electroactive alloy of a semi-metal and an electroactive compound of a metal or a semi-metal. The polymeric binder has a molecular weight in the range 300,000 to 3,000,000. 40 to 90% of the carboxyl groups of the binder are in the form of a metal ion carboxylate salt.

Abstract: Composite electrode material for a rechargeable battery cell includes an electroactive material; and a polymeric binder including pendant carboxyl groups, characterized in that (i) the electroactive material includes one or more components selected from the group including an electroactive metal, an electroactive semi-metal, an electroactive ceramic material, an electroactive metalloid, an electroactive semi-conductor, an electroactive alloy of a metal, an electroactive alloy of a semi metal and an electroactive compound of a metal or a semi-metal, (ii) the polymeric binder has a molecular weight in the range 300,000 to 3,000,000 and (iii) 50 to 90% of the carboxyl groups of the polymeric binder are in the form of a metal ion carboxylate salt. A method of making a composite electrode material, an electrode, cells including electrodes and devices using such cells are also disclosed.

Abstract: A lithium ion rechargeable battery cell includes an anode having electroactive material-containing particles wherein the electroactive material is selective from one or more of silicon, germanium, and tin. A cathode includes an active material adapted to incorporate lithium and also to liberate lithium electrochemically. The anode is adapted to incorporate lithium during lithiation. Also provided is an electrolyte, wherein the electrolyte includes both a cyclic carbonate having a vinyl group and a fluorinated cyclic carbonate. The total amount of the cyclic carbonate including a vinyl group and the fluorinated cyclic carbonate together is in the range of 3.5 wt % to 70 wt % based on the total weight of the electrolyte solution.

Abstract: A lithium ion rechargeable battery cell includes an anode having electroactive material-containing particles wherein the electroactive material is selective from one or more of silicon, germanium, and tin. A cathode includes an active material adapted to incorporate lithium and also to liberate lithium electrochemically. The anode is adapted to incorporate lithium during lithiation. Also provided is an electrolyte, wherein the electrolyte includes both a cyclic carbonate having a vinyl group and a fluorinated cyclic carbonte. The total amount of the cyclic carbonate including a vinyl group and the fluorinated cyclic carbonate together is in the range of 3.5 wt % to 70 wt % based on the total weight of the electrolyte solution.

Abstract: The present invention claims the addition of vinylene carbonate (VC) and optionally also fluoroethylene carbonate to the electrolyte of lithium ion cells having a structural silicon composite anode, i.e. an anode containing fibers or particles of silicon. The additive significantly improves the cycling performance of the cells. A VC content in the range 3.5-8 wt % based on the weight of the electrolyte has been found to be optimum.

Abstract: Disclosed are a composite electrode material for a rechargeable battery; a method of making a composite electrode material; an electrode including the composite electrode material; cells including such electrodes; and devices including the cells. A composite electrode material for a rechargeable battery cell includes an electroactive material; and a polymeric binder including pendant carboxyl groups. The electroactive material includes one or more components selected from the group including an electroactive metal, an electroactive semi-metal, an electroactive ceramic material, an electroactive metalloid, an electroactive semi-conductor, an electroactive alloy of a metal, an electroactive alloy of a semi-metal and an electroactive compound of a metal or a semi-metal. The polymeric binder has a molecular weight in the range 300,000 to 3,000,000. 40 to 90% of the carboxyl groups of the binder are in the form of a metal ion carboxylate salt.

Abstract: The present invention claims the addition of vinylene carbonate (VC) and optionally also fluoroethylene carbonate to the electrolyte of lithium ion cells having a structural silicon composite anode, i.e. an anode containing fibres or particles of silicon. The additive significantly improves the cycling performance of the cells. A VC content in the range 3.5-8 wt % based on the weight of the electrolyte has been found to be optimum.

Abstract: An electrode for lithium ion recharged battery cell includes current collectors, a cathode layer, a separator and a cohesive anode mass. The cohesive anode mass includes silicon as an active material and a polymeric binder. The polymeric binder is a homo-polymer or copolymer of one or more monomers selected from the group consisting of acrylic acid, 3-butenoic acid, 2-methacrylic acid, 2-pentenoic acid, 2,3-dimethylacrylic acid, 3,3-dymethylacrylic acid, trans-butenedioc acid, cis-butenedioc acid and itaconic acid and optionally an alkali metal salt thereof. The silicon can include 20 to 100% of the active material in the cohesive mass. The binder is mixed with the silicon to form the cohesive mass that adheres to the current collector and maintains the cohesive mass in electrical contact with the current collector.

Abstract: Composite electrode material for a rechargeable battery cell includes an electroactive material; and a polymeric binder including pendant carboxyl groups, characterised in that (i) the electroactive material includes one or more components selected from the group including an electroactive metal, an electroactive semi-metal, an electroactive ceramic material, an electroactive metalloid, an electroactive semi-conductor, an electroactive alloy of a metal, an electroactive alloy of a semi metal and an electroactive compound of a metal or a semi-metal, (ii) the polymeric binder has a molecular weight in the range 300,000 to 3,000,000 and (iii) 50 to 90% of the carboxyl groups of the polymeric binder are in the form of a metal ion carboxylate salt. A method of making a composite electrode material, an electrode, cells including electrodes and devices using such cells are also disclosed.

Abstract: Lithium ion cells in which the cathode contains a particulate insertion material and a binder are cut open in a dry, inert atmosphere (10). The cell components are treated with a first organic solvent (12) to dissolve the electrolyte, so that this can be reused. They are then treated with a second organic solvent (16) to dissolve the binder, and the particulate material separated (18) from the solution of binder. The insertion material is then reduced (22) so that it does not contain intercalated lithium. The reduction process may be performed electrolytically.

Abstract: An electrolyte for use in a rechargeable cell whose charging voltage exceeds 3.8 volts includes a redox chemical comprising a substituted aromatic molecule in which &agr; hydrogens are either absent, or are sterically against loss from the ionized form of the molecule. Such as chemical can act as a redox shuttle during overcharge, suppressing damage to the cell and preventing the deposition of metallic lithium during the overcharge of a lithium ion cell, but does not affect normal operation of the cell during either charge or discharge. One such molecule is hexaethyl benzene.