Integrated and modular BSP/MEA/manifold plates for fuel cells

Abstract

The present invention concerns improvements in fuel cell fabrication. It concerns an improved, integrated and modular BSP/MEA/Manifolds, which facilitates single cell (module) leak and performance testing prior to assembly in a fuel cell stack as well as facilitating manufacturing and cost reduction. In particular, the present invention relates to a fuel cell, which includes: a) A single flexible or ridged separator plate; b) a flexible membrane electrode assembly; c) a flexible bond interposed between said single flexible or ridged separator plate and said flexible membrane electrode assembly, wherein said flexible bond between said flexible or ridged separator plate and said flexible membrane electrode assembly comprises the fuel cell, and wherein said flexible bond is an adhesive bond which encapsulates edge portions of said flexible or ridged separator plate and said flexible membrane electrode assembly and wherein said flexible bond seals the edge portions of said flexible membrane assembly to prevent the release of reactants from the fuel cell. In some embodiments the adhesive bond comprises a flexible gasket; d) manifold for the delivery and removal of reactants and reactant products to and from the fuel cell reactive areas where said manifolds may be either a single or multiple manifolds; and e) a bond interposed between said manifold and said single flexible or ridged separator plate, wherein said bond affixes said manifold to said flexible or ridged separator plate and wherein said bond provides a seal between said manifold and said flexible or ridged separator plate to prevent the release of reactants from the fuel cell. It also eliminates some gaskets and simplifies assembly.

Description

[0001] This application is a continuation-in-part of U.S. Ser. No. 60 / 226,471, filed Aug. 18, 2000 and U.S. Ser. No. 60 / 249,662, filed Nov. 17, 2000, and U.S. Ser. No. ______, filed Apr. 13, 2001 by Express Mail No.: EL700013365US, all of which are incorporated herein by reference in their entirety.[0002] 1. Field of the Invention[0003] The present invention relates to electrochemical energy converters with a polymer electrolyte membrane (PEM), such as fuel cells or electrolyzer cells or stacks of such cells, wherein the individual cells are modular units which have integrated the bipolar separator plate (BSP), the membrane electrode assembly (MEA) and the reactant and coolant manifolds. These individual components are assembled into integrated modules and these modules are tested individually for full functionality before being assembled into a complete fuel cell unit (stack) as individual components. In particular the several components of the integrated modular BSP / MEA / Manifolds ...

AI Technical Summary

Problems solved by technology

Disassembly and analysis of fuel cell stacks built by traditional and other methods reveals evidence of incomplete electrical contact between bipolar separator plates (BSPs) 8 and the membrane electrode assembly (MEAs) 9, which results in poor electrical conduction, lower cell performance, often along with evidence of gas and liquid leakage.

The assembly of a traditional PEM cell stack which comprises a plurality of PEM cells each having many separate gaskets which must be fitted to or formed on the various components is labor-intensive, costly and in a manner generally unsuited to high volume manufacture due to the multitude of parts and number of assembly steps required.

With the conventional PEM stack design 1, see FIG. 2, it is problematic to remove and repair an individual cell 2 (see FIG. 3) or to identify or test which cell or cells in the stack may require repair due to leakage or performance problems.

The disassembly of a stack consisting of multiple cells, each comprising separate cell components can be very costly as in many instances, after the removal of one cell, the gaskets of the remaining cells may need to be replaced before the stack can be reassembled and operated.

Additionally, the potential for damage to the MEA is very high.

Upon reassembly, there is no assurance of the performance or of a leak tight condition.

This is a very time consuming and therefore costly process.

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