Title of Invention

A COOLANT FLOW FIELD PLATE FOR A FUEL CELL

Abstract

A coolant flow field plate for a fuel cell is characterised by a plurality of vertically and parallely disposed channels C.Each channel is open at the top and at the bottom. A horizontally disposed passage pt at the top communicates with the open ends of each channel at the top and a horizontally disposed passage at the bottom Pb communicates with the open ends of each channel at the bottom. The coolant inlet I is in communication with the passage at the bottom open and the coolant outlet 0 is in comm unication with the passage at the top.

Full Text

This invention relates to a coolant flow field plate for a fuel cell. Fuel cells are power generation devices that produce an electric current through an electrochemical reaction of a fuel and an oxidant The most common fuels used in the fuel cell reaction is hydrogen gas which itself could be derived from a variety of sources. "Hie oxidant could be either pure oxygen or air. Since the theoretical voltage obtained from a hydrogei\/oxygen fuel cell is only 1.23 volts per cell, it is common practice to assemble several cells in series to form a friel cell stack. Fuel and oxidant gases are supplied to the individual cells through manifolds and are then distributed inside single celts along passages or channels in flow field plates so as to supply reactant gases to the entire area of the electrodes, namely, the cathode and the anode. Fuel gas (a mixture containing hydrogen or pure hydrogen) is fed to the anode and oxidant gas (air or oxygen) is supplied to the cathode via the respective flow field plates. At tfie cathode hydrogen ions from the anode and oxygen react electrochemically giving rise to an electric current and forming water as a product. In addition to an electric current all fuel cells produce heat due to the exothermic heat of reaction and due to the internal resistance of the fiiel cell components; a major part of this heat needs to be continuously removed for example by circulating a coolant so as to maintain the fuel cell at the preferred operating temperature. The coolant flow field plate for a fuel cell proposed herein achieves efficient cooling as well as contributes towar Various other features and advantages of this invention will be apparent from the following further description thereof The coolant flow field plate for a fuel cell, according to this invention, comprises a plurality of vertically and parallely disposed channels, characterized in that each chamel is open at the top and at the bottom; a horizontatly disposed passage at the top, communicating with the open ends of each channel at the top; and a horizontally disposed passage at the bottom, communicating with the open ends of each channel at the bottom, the coolant inlet being in communication with the passage at the bottom and the coolant outlet being in communication with the passage at the top. This invention will now be described with reference to the accompanying drawing which illustrates, by way of example, and not by way of limitation, the salient features of one of various possible embodiments of this invention. A plurality of vertically and parallely disposed channels C are provided in the coolant plate, each open at the top at T and at the bottom at B. A horizontally disposed passage Pt at the top, communicates with the open ends of each channel at the top. A horizontally disposed passage Pb at the bottom, communicates with the open ends of each channel at the bottom. The coolant inlet I is in communication with the passage Pb at the bottom and the coolant outlet O is in communication with the passage Pt at the top. The aforementioned features provide for better cooling since the coolant is made to flow generally from the bottom to the top through the shortest path through multiple channels. The resultant low pressure drop for flow allows a coolant circulation pump of very small capacity to be used, thus reducing parasitic power consumption. This design also brings about a more even temperature distribution across the surface of the coolant plate (and hence in the fuel cell) because of the use of a large number of chaimels having the shortest possible length. The terms and expressions in this specification are of description and not of limitation, there being no intention in excluding any equivalence of the features illustrated and described, but it is understood that various other embodiments of the coolant flow field plate for a fiiel cell stack proposed herein are possible without departing from the scope and ambit of this invention. We Claim: l.A coolant flow field plate for a fuel cell comprising a plurality of vertically and paralleiy disposed channels, characterized in that each channel is open at the top and at the bottom; a horizontally disposed passage at the top, communicating with the open ends of each channel at the top; and a horizontally disposed passage at the bottom, communicating with the open ends of each channel at the bottom, the coolant inlet being in communication with the passage at the bottom and the coolant outlet being in communication with the passage at the top. 2.A coolant flow field plate for a fuel cell substantially as herein described and illustrated by the accompanying drawing. I

Documents:

0552-mas-2001 abstract-duplicate.pdf

0552-mas-2001 abstract.pdf

0552-mas-2001 claims-duplicate.pdf

0552-mas-2001 claims.pdf

0552-mas-2001 correspondence-others.pdf

0552-mas-2001 correspondence-po.pdf

0552-mas-2001 description (complete)-duplicate.pdf

0552-mas-2001 description (complete).pdf

0552-mas-2001 drawings.pdf

0552-mas-2001 form-1.pdf

0552-mas-2001 form-19.pdf

0552-mas-2001 form-26.pdf