Abstract: A secondary energy storage element includes a reference electrode or a constituent thereof positioned between at least one ply of a separator layer and one of electrode layers and electrically insulated from the electrode layer by an insulating means, the reference electrode or the constituent thereof positioned such that there is at least one metal filament or a sheet-shaped metallic coating on a surface of the at least one ply of the separator layer or a surface of the insulating means, within an overlap region the at least one metal filament or the sheet-shaped metallic coating is arranged on the surface of a ply of the separator layer or a surface of the insulating means, and the at least one metal filament or the sheet-shaped metallic coating covers on the surface an area of a maximum of 5% of the area over which the overlap region extends.

Abstract: A secondary electrochemical cell includes a negative electrode including as an output conductor, a metallic or metal-coated open-pore form or a metallic or metal-coated nonwoven, as a carbon-based storage material that enables storage of electrical charge in the electrode through formation of an electrical double layer (Helmholtz double layer), activated carbon having a BET surface area of at least 800 m2/g, a non-carbon-based H2 storage material that can chemisorb hydrogen and/or store it as a metal hydride, a positive electrode including as an output conductor, a metallic or metal-coated open-pore form or a metallic or metal-coated nonwoven, and nickel hydroxide and/or nickel oxyhydroxide, a porous separator that separates the negative electrode and the positive electrode from one another, an aqueous alkaline electrolyte with which the electrodes and the separator are soaked, and a housing that encases the electrodes, the separator and the electrolyte.

Abstract: A secondary energy storage element includes a reference electrode or a constituent thereof positioned between at least one ply of a separator layer and one of electrode layers and electrically insulated from the electrode layer by an insulating means, the reference electrode or the constituent thereof positioned such that there is at least one metal filament or a sheet-shaped metallic coating on a surface of the at least one ply of the separator layer or a surface of the insulating means, within an overlap region the at least one metal filament or the sheet-shaped metallic coating is arranged on the surface of a ply of the separator layer or a surface of the insulating means, and the at least one metal filament or the sheet-shaped metallic coating covers on the surface an area of a maximum of 5% of the area over which the overlap region extends.

Abstract: A secondary electrochemical cell includes a negative electrode including as an output conductor, a metallic or metal-coated open-pore form or a metallic or metal-coated nonwoven, as a carbon-based storage material that enables storage of electrical charge in the electrode through formation of an electrical double layer (Helmholtz double layer), activated carbon having a BET surface area of at least 800 m2/g, a non-carbon-based H2 storage material that can chemisorb hydrogen and/or store it as a metal hydride, a positive electrode including as an output conductor, a metallic or metal-coated open-pore form or a metallic or metal-coated nonwoven, and nickel hydroxide and/or nickel oxyhydroxide, a porous separator that separates the negative electrode and the positive electrode from one another, an aqueous alkaline electrolyte with which the electrodes and the separator are soaked, and a housing that encases the electrodes, the separator and the electrolyte.

Abstract: A secondary electrochemical cell includes a negative electrode including an output conductor, activated carbon having a BET surface area of at least 800 m2/g as a carbon-based storage material that enables storage of electrical charge in the electrode through formation of an electrical double layer (Helmholtz double layer), a positive electrode including an output conductor, and nickel hydroxide and/or nickel oxyhydroxide, a porous separator that separates the negative electrode and the positive electrode from one another, an aqueous alkaline electrolyte with which the electrodes and the separator are soaked, and a housing that encases the electrodes, the separator and the electrolyte.