Battelle Memorial Institute

Delphi Technologies, Inc.

K Scott Weil

Vincent L Sprenkle

Kerry D Meinhardt

John S Hardy

Karl Jacob Haltiner, Jr

Subhasish Mukerjee

Paul E George, Ii

Jin Yong Kim

Lawrence Andrew Chick

Dean Paxton

Kurtis P Recknagle

John E Deibler

Dean Michael Paxton

Solid-oxide fuel cell (SOFC) stack assembly designs are consistently investigated to develop an assembly that provides optimal performance, and durability, within desired cost parameters. A new design includes a repeat unit having a SOFC cassette and being characterized by a three-component construct. The three components include an oxidation-resistant, metal window frame hermetically joined to an electrolyte layer of a multi-layer, anode-supported ceramic cell and a pre-cassette including a separator plate having a plurality of vias that provide electrical contact between an anode-side collector within the pre-cassette and a cathode-side current collector of an adjacent cell. The third component is a cathode-side seal, which includes a standoff that supports a cathode channel spacing between each of the cassettes in a stack. Cassettes are formed by joining the pre-cassette and the window frame.

Cassettes for solid-oxide fuel cell stacks and methods of making the same

A joint for use in electrochemical devices, such as solid oxide fuel cells (SOFCs), oxygen separators, and hydrogen separators, that will maintain a hermetic seal at operating temperatures of greater than 600&#xb0; C., despite repeated thermal cycling excess of 600&#xb0; C. in a hostile operating environment where one side of the joint is continuously exposed to an oxidizing atmosphere and the other side is continuously exposed to a wet reducing gas. The joint is formed of a metal part, a ceramic part, and a flexible gasket. The flexible gasket is metal, but is thinner and more flexible than the metal part. As the joint is heated and cooled, the flexible gasket is configured to flex in response to changes in the relative size of the metal part and the ceramic part brought about by differences in the coefficient of thermal expansion of the metal part and the ceramic part, such that substantially all of the tension created by the differences in the expansion and contraction of the ceramic and metal parts is absorbed and dissipated by flexing the flexible gasket.

Joint with application in electrochemical devices

A modular fuel cell cassette for use in assembling a fuel cell stack comprising a metal separator plate and a metal cell-mounting plate joined at their edges to form a hollow cassette. A fuel cell subassembly is attached to the mounting plate and extends through an opening in the mounting plate. The plates include openings to form chimney manifolds for supply and exhaust of fuel gas to the anode and air to the cathode. A conductive interconnect element extends from the fuel cell subassembly to make contact with the next cassette in a stack. The anode openings in the mounting plate and separator plate are separated by spacer rings such that the cassette is incompressible. A fuel cell stack comprises a plurality of cassettes, the mounting plate of one cassette being attached to, and insulated from, the separator plate of the next-adjacent cassette by a dielectric seal surrounding the interconnect.

Modular fuel cell cassette for forming a solid-oxide fuel cell stack

A method of joining metal and ceramic parts, wherein an alumina forming metal part and a ceramic part are provided. A braze material in placed between the alumina forming metal part and the ceramic part, and the combination is then heated in an oxidizing atmosphere, preferably in air at a temperature of between 500&#xb0; C. and 1300&#xb0; C. The alumina forming metal parts are selected from the group consisting of high temperature stainless steels, such as Durafoil (alpha-4), Fecralloy, Alumina-coated 430 stainless steel and Crofer-22APU, and high temperature superalloys such as Haynes 214, Nicrofer 6025, and Ducraloy. The braze material is selected as a metal oxide-noble metal mixture, preferably Ag&#x2014;CuO, Ag&#x2014;VO, and Pt&#x2014;NbO, and more preferably between 30.65 to 100 mole % Ag in CuO.

Oxidation ceramic to metal braze seals for applications in high temperature electrochemical devices and method of making

Growing community of inventors

Richland, WA, United States of America

K Scott Weil