Abstract: The method for reusing current collectors/distributors is employed in an electrochemical generator (1, 20) comprising a multiplicity of elementary cells (2, 21) assembled in a filter-press configuration and comprising an array of conductive sheets (3) and of current collectors/distributors (7, 22). The method of the invention provides dissembling the electrochemical generator (1) once the presence of a damaged elementary cell (2, 21) is detected. Subsequently, the method of the invention provides repairing/replacing the damaged cell for later reassembling the electrochemical generator (1, 20) reusing the original current collectors/distributors (7, 22). to achieve this, while reassembling the electrochemical generator (1, 20), a mechanical means for adapting (8, 12, 13, 14, 15) is inserted between each conducting sheet (3) and the respective current collector/distributor (7, 21).

Abstract: An improved design of gas fed polymeric membrane fuel cell stack is herein described. The stack is provided with a humidifying device which takes advantage of the atomization of a water stream over a high specific surface metallic material, and with a cooling circuit withdrawing the heat generated therein by thermal exchange on a peripheral region, external to the single cell active area. The device is particularly suited for high temperature and high current density operation.

Abstract: The invention relates to a stack of polymeric membrane fuel cells, wherein the removal of the heat generated by the production of electric energy and the humidification of the ion exchange membranes used as electrolytes are obtained by the direct injection of a water flow coming from a single hydraulic circuit. The stack thus produced is more compact, less expensive and easier to operate.

Abstract: The method for reusing current collectors/distributors is employed in an electrochemical generator (1, 20) comprising a multiplicity of elementary cells (2, 21) assembled in a filter-press configuration and comprising an array of conductive sheets (3) and of current collectors/distributors (7, 22). The method of the invention provides dissembling the electrochemical generator (1) once the presence of a damaged elementary cell (2, 21) is detected. Subsequently, the method of the invention provides repairing/replacing the damaged cell for later reassembling the electrochemical generator (1, 20) reusing the original current collectors/distributors (7, 22). to achieve this, while reassembling the electrochemical generator (1, 20), a mechanical means for adapting (8, 12, 13, 14, 15) is inserted between each conducting sheet (3) and the respective current collector/distributor (7, 21).

Abstract: A humidification device for polymeric membrane fuel cell stacks fed with gaseous reactants is disclosed. The gases supplied to the stack are previously fed in admixture with a stream of liquid water to a chamber filled with a reticulated material, whose highly subdivided geometry provides an extended exchange surface favouring the saturation of gas. The device is more efficient and compact than those known in the art.

Abstract: An improved design of gas fed polymeric membrane fuel cell stack is herein described. The stack is provided with a humidifying device which takes advantage of the atomisation of a water stream over a high specific surface metallic material, and with a cooling circuit withdrawing the heat generated therein by thermal exchange on a peripheral region, external to the single cell active area. The device is particularly suited for high temperature and high current density operation.

Abstract: The dual power unit includes an elongate housing having mounted therein adjacent opposite ends thereof two power units, one of which is drivingly connected to the movable back of an armchair, and the other unit is connected to a movable footrest of an armchair. Each unit includes a pivotal shaft connected to the back or footrest of the armchair. Each such shaft is connected to the output shaft of an electronic motor reducer through a transmission-gear in the form of a screw extending transversely of the respective pivotal shaft. The screw is drivingly connected through a threaded slider which is in engagement with a pair of cam elements mounted on a respective pivotal shaft to impart pivotal movement thereto, and consquent movement to the portion of the armchair connected thereto.

Abstract: A method of detecting a condition requiring connection of a user apparatus with a feeder line comprises the steps of low-voltage power supplying the user apparatus through a detection impedance (17, 17a); detecting the waveform at the ends of the detection impedance; operating connection of the user apparatus with the feeder line when the waveform at the ends of the detection impedance is distorted in a manner that has been pre-established to be caused by actuation of a command in the user apparatus and requiring full powering of same. A device in accordance with the method comprises an analysis circuit (19, 37) detecting (by comparison with sample waveforms stored in a memory (20), for example) distortion of the waveform at the ends of the impedance (17, 17a) and consequently operating powering of the user apparatus.

Abstract: The present invention refers to an electrochemical cell or stack of cells comprising two end-plates (7), bipolar plates (1) made of metal or metal alloy, gas permeable metal distributors (2), metal current collectors(3), gasket frames (4) provided with channels for feeding the gaseous reactants and discharging the excess reactants and condensates, a couple of gas diffusion electrodes, (5), an ion-exchange membrane (6), wherein said current conductors provide for a highly distributed segmented contact area on the electrode surface without isolated peaks and have an extremely smooth surface without asperities and at the same time porous and permeable to the gas flow.

Abstract: The invention concerns membrane electrolyzers suitable for processes such as water or hydrogen halides electrolysis, as well as electrochemical generators fed with gases containing hydrogen and oxygen for direct conversion into electric energy. These apparatuses generally consist of a filter-press assembly of conductive bipolar plates (2), electrodes (4), sealing gaskets (5) membranes (6) and internal longitudinal ducts for feeding the reactants and withdrawing the products and residual reactants. The invention is directed to the method for repairing said electrolyzers or generators when an elementary cell is malfunctioning. This method comprises making at least two perforations in the peripheral area of the bipolar plates (2) and/or gaskets (5) of the malfunctioning cell to reach distribution channels (9, 11) which connect the compartments containing the electrodes (4) with said longitudinal ducts.