Abstract:
The invention relates to an electrochemical fuel cell stack comprising a membrane-electrode-unit and a distributor plate comprising a channel area with gas channels for distributing anode or cathode gas to the membrane-electrode-unit, a portal area for supplying anode and/or cathode gas into the channel area and a portal area for removing anode and/or cathode gas from the channel area. According to the invention, the gas channels in the channel area of the distributor plate are not combined in a bundle but are disentangled and distributed over on a plurality of separated channel regions. A gas channel extends exactly in a channel region, with at least one deviation between the portal areas for supplying and removing anode and/or cathode gas.
Abstract:
An air breathing direct methanol fuel cell is provided with a membrane electrode assembly (14), a conductive cathode assembly (18) that is permeable to air and directly open to atmospheric air, and a conductive anode assembly (16) that is permeable to methanol and directly concacting a liquid methanol source (12). Water loss from the cell is minimized by making the conductive cathode assembly (18) hydrophobic and the conductive anode assembly (16) hydrophilic.
Abstract:
A solid state electrochemical device incorporating planar sheets (11) of cathode flow passages, in varying configurations and geometries, with thin coatings of electrolyte, anode and interconnect materials, which when assembled and bonded together form a monolithic honeycomb structure defining tubular passages for the passages inside the cell plates, while fuel will flow through passages formed between adjacent cells. Electrically insulating manifolds (15, 17), designed to keep the fuel and air separate, are bonded at each end of the honeycomb. The fuel cell stack and manifolds are encased in a metal housing (9, 10) or cover (19, 20) to provide the outer walls of the manifold, complete the package, and define a discrete fuel cell module that can be used singly or in groups in fuel cell power generation systems.
Abstract:
The invention relates to an fuel cell stack, comprising alternately arranged membrane-electrode units (3) and separator plates (2, 2a) for the introduction and removal of the reactant and oxidative fluid, whereby the separator plate (2, 2a) has a surface structure and the opposing face has the negative surface structure, by means of a stamping process. According to the invention, on stacking the separator plates (2, 2a), the surface structure of a separator plate (2) is opposite the corresponding negative surface structure of the adjacent separator plate (2a).
Abstract:
The invention relates to a low-temperature fuel cell in which the transport of operating materials is distinctly improved by utilizing centrifugal force. The invention provides, in an advantageous embodiment, that the fuel cell, which is designed with rotational symmetry, are rotated. The operating materials are supplied via the rotational axis. Water is advantageously evacuated from the cathode space via the non-rotating outer housing.
Abstract:
Fuel cells (1) are stacked, supported and electrically connected into a battery structure with a connector block (20). The anode and cathode elements of each fuel cell are provided with conductive terminating elements, preferably extending downward U-shaped configuration from the upper ends of the elements. The connector block comprises a series of conductive apertures which positioned and sized to accommodate the conductive terminating elements. When the terminating elements and apertures are engaged, the connector block mechanically supports the anodes and cathodes. This arrangement also permits selective rapid cell removal for replacement or servicing. The connector block also includes electrically conductive elements which electrically connect the fuel cells in a desired interconnection, which may be serial, parallel, or mixed. The cells are also provided with keyed members for interlocking with a support tray (45) having cof-itting keyed elements (41). Lateral end elements extend between the connector block and support tray to complete and open enclosure. Air is circulated through a duct (50) defined by the connector block.
Abstract:
The invention relates to a device with a fuel cell or a stack of fuel cells, wherein one electrode of a fuel cell is separated from an adjoining channel or chamber through which an operating substance is supplied by means of a perforated plate. The size and/or the density of the holes increases towards the edge starting from a median line and the median line extends in parallel to the direction of flow of the operating substance. The inventive device more reliably avoids thermal gradients in the interior of the fuel cell or of a stack of fuel cells. In order to prevent the occurrence of temperature gradients, the device is cooled by evaporating a coolant in an external cooling system. The heat is mainly transferred by thermal radiation.
Abstract:
A solid polymer fuel cell stack includes a rectangular separator, the surface of which includes coolant channels in a region that is substantially parallel to the long side of the separator and near channels for fuel gas or oxidizing gas so that the cooling may flow in a direction perpendicular to the separator plane.
Abstract:
In a PEM-type fuel cell, coolant conduits (40) are provided that follow the reactant gas flowpaths (28) on either side of the MEA layer, either within a space that otherwise would have been part of the reactant gas flowpaths, or nearby. The positioning of the coolant conduits is selected to permit them to remove heat effectively from the fuel cell while lying in relatively space-inefficient portion of the fuel cell, preferably a space that would have, were it not for the presence of the coolant conduits, have been occupied by a relatively space-inefficient portion of the flowpaths. These coolant conduits can eliminate the need for coolant conduits that pass in the stack dimension through the MEA layers.
Abstract:
A PEM-type fuel cell is formed from layered undulate MEA structures (25) and separator strata (20) alternating with each other in the stack dimension so that each layered MEA structure is disposed between and attached to an associated pair of separator strata so as to form at least one discrete plenum on each side of each layered MEA structure through which plenum reactant gas may be circulated. Each layered MEA structure is formed from proton exchange membrane material (14) sandwiched between a pair of spaced-apart current collectors (22, 24) with electro-catalyst particles between the membrane material and each current collector so that the membrane material and electro-catalyst particles fill the space between the current collectors, forming together with the current collectors a layered MEA structure. Each separator stratum is attached to and provides an electrically conductive path between the current collectors of the layered MEA structures on either side of the separator stratum.