US 7,125,625 B2 · Electrochemical cell and bipolar assembly for an electrochemical cell

Abstract

A bipolar assembly for use in electrochemical cell stacks, especially stacks operated at low pressure. The bipolar assembly is lightweight and provides a “post-type” flow field that operates with a low pressure drop. The bipolar assembly comprises a gas barrier having an array of electronically conducting posts disposed approximately perpendicular to the gas barrier. Each end of the posts is in electrical communication with the surface of an electrode. Because the bipolar assembly separates a cathode from an anode, the posts contact an anode electrode on one end and a cathode electrode on the other end. The posts provide current conduction through the stack as well as provide the flow fields for the electrochemical reactants. Optionally, the bipolar assembly may contain cooling fluid channels formed by adding additional gas barriers to the bipolar assembly. The space between the gas barriers form a channel through which cooling fluids may be circulated.

Claims53

Dependent claims

A fluid-cooled assembly for use in an electrochemical cell stack comprising:

at least two gas barriers, wherein a first gas barrier opposes an anode electrode and a last gas barrier opposes a cathode electrode and wherein the gas barriers are approximately parallel;
and
an array of electronically conductive protrusions disposed across the gas barriers, wherein the electronically conductive protrusions enable electrical communication between the anode electrode and the cathode electrode, wherein the protrusions are inserted into an array of holes, indentations, or combinations thereof in the gas barriers, and wherein the protrusions have a cross section approximately matching a cross section of the holes or indentations, and wherein the gas barriers and the protrusions are metallic;
and
seals around the protrusions formed by metallurgically bonding the protrusions to the gas barriers, wherein the seal is formed with a metal having a melting point substantially lower than the metals of the protrusions or the gas barriers.

2 more elements

Dependencies are inferred from the claim text.

Electrochemical cell and bipolar assembly for an electrochemical cell

Life of this patent

Electrochemical cell and bipolar assembly for an electrochemical cell

Life of this patent

Abstract

Claims53