Chemical bonding for catalyst/membrane surface adherence in membrane electrolyte fuel cells

• US 10,096,838 B2
• Filed: 06/06/2011
• Issued: 10/09/2018
• Est. Priority Date: 06/07/2010
• Status: Active Grant

• Current Assignee: Hydrolite Limited
• Original Assignee: POCell Tech Ltd.
• Inventors: Dekel, Dario
• Primary Examiner(s): Vo, Jimmy
• Application Number:
  US13/154,056
• Publication Number:
  US 20110300466A1
• Time in Patent Office: 2,682 Days
• Field of Search: 429465, 429480, 429482, 429510, 429535
• CPC Class Codes: H01M 4/881 Electrolytic membranes
• CPC Class Codes: H01M 4/8817 Treatment of supports before application of the catalytic active composition coated porous composites H01M8/0245
• CPC Class Codes: H01M 8/1018 Polymeric electrolyte materials
• CPC Class Codes: H01M 8/102 characterised by the chemical structure of the main chain of the ion-conducting polymer
• CPC Class Codes: H01M 8/1053 consisting of layers of polymers with at least one layer being ionically conductive
• CPC Class Codes: Y02E 60/50 Fuel cells
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product

Abstract

An alkaline membrane fuel cell including at least one of i) a catalyst coated OH— ion conducting membrane having a catalyst layer and an OH— ion conducting membrane, and ii) a catalyst coated carbonate ion conducting membrane having a catalyst layer and a carbonate ion conducting membrane, respectively, wherein the at least one catalyst layer is chemically bonded to a surface of the at least one membrane, wherein the chemical bonding is established by crosslinking of polymer constituents across an interface between the at least one catalyst layer and the at least one membrane.

Claims

1. An alkaline membrane fuel cell comprising:

a catalyst coated OH—

ion conducting membrane having a catalyst layer and an OH—

ion conducting membrane comprising a hydrocarbon backbone with C1-C6 alkyl side chains and a cation bonded to the side chain enabling OH—

ion conduction, wherein the catalyst layer is directly chemically bonded to a surface of the membrane, via covalent bonding, wherein the covalent chemical bonding is established by crosslinking of polymer constituents across an interface between the at least one catalyst layer and the membrane;

wherein an overall crosslinking region includes at least some volume of each of the catalyst layer and the membrane, and wherein the catalyst layer comprises compounds or agents having one or more crosslinking groups that form chemical bonds with one or more ionomeric functionalities of both the catalyst layer and the ion conducting membrane.

2. The alkaline membrane fuel cell of claim 1, wherein the cations in the conducting membrane include at least one of quaternary phosphonium and quaternary ammonium groups.

3. The alkaline membrane fuel cell of claim 1, wherein the crosslinking is established using diphosphines, triphosphines, monophosphine and diphosphines mixtures, diamines, triamines, monoamine and diamine mixtures, and any phosphine or amine having the general formula:

(RIR2)X—

R—

X(R3R4) where X is a P or N atom, RI and R2, R3 and R4 are C1-C6 alkyl groups, independent of each other or forming a ring with each other; and

R includes a spacer in the molecular structure selected to optimize the length of the molecule.

4. A membrane electrode assembly for alkaline membrane fuel cell including the catalyst coated membrane of claim 1 and a pair of gas diffusion layers, wherein the catalyst coated membrane is prepared as set forth in claim 1.

5. An alkaline membrane fuel cell stack including a plurality of membrane electrode assemblies as set forth in claim 4.