Abstract: The invention concerns an electrical energy storage assembly (capacitor or battery) comprising: -an envelope (20) including: *at least one lateral wall (21), and *an open end, -an electrochemical element (30) intended to be contained in the envelope (20) and -at least one cover (40) intended to be positioned at the open end of the envelope (20), each cover (40) including: *a cover wall (41, 45) intended to cover the open end of the envelope (20), *a lateral face (42, 43) at the periphery of the cover wall (41, 45) and intended to be facing the lateral wall (21) of the envelope (20), -at least one electrically insulating elastic annular ring (50) intended to be positioned between the lateral wall (21) of the envelope (20) and the lateral wall (42, 43) of the cover (40).

Abstract: The invention concerns an electrical energy storage assembly (capacitor or battery) comprising: -an envelope (20) including: *at least one lateral wall (21), and *an open end, -an electrochemical element (30) intended to be contained in the envelope (20) and -at least one cover (40) intended to be positioned at the open end of the envelope (20), each cover (40) including: *a cover wall (41, 45) intended to cover the open end of the envelope (20), *a lateral face (42, 43) at the periphery of the cover wall (41, 45) and intended to be facing the lateral wall (21) of the envelope (20), -at least one electrically insulating elastic annular ring (50) intended to be positioned between the lateral wall (21) of the envelope (20) and the lateral wall (42, 43) of the cover (40).

Abstract: The present invention relates to a device to prevent overpressure in a supercapacitor. In a supercapacitor comprising a closed chamber fitted with means for exchanging a gas with the external surroundings and in which there are positioned two electrodes with a high specific surface area, separated by a separator, the separator and the electrodes being impregnated with an electrolyte, the means for exchanging a gas comprise a metallic membrane that is permeable to hydrogen and its isotopes and impermeable to gaseous species which have an effective cross section of 0.3 nm or higher, at a temperature of between ?50° C. and 100° C.

Abstract: The present invention relates to a device to prevent overpressure in a supercapacitor. In a supercapacitor comprising a closed chamber fitted with means for exchanging a gas with the external surroundings and in which there are positioned two electrodes with a high specific surface area, separated by a separator, the separator and the electrodes being impregnated with an electrolyte, the means for exchanging a gas comprise a metallic membrane that is permeable to hydrogen and its isotopes and impermeable to gaseous species which have an effective cross section of 0.3 nm or higher, at a temperature of between ?50° C. and 100° C.