Method for producing a current collector for a fuel cell, and fuel cell

Patent metadata

Field	Value
Publication number	US-10862137-B2
Application number	US-201716319551-A
Country	US
Kind code	B2
Filing date	Jul 12, 2017
Priority date	Jul 25, 2016
Publication date	Dec 8, 2020
Grant date	Dec 8, 2020

Abstract

The invention relates to a method for producing a current collector ( 1 ) for a fuel cell. The method comprises the following steps: mixing a power-type or granulate-type base material ( 2 ) with a binding agent ( 3 ) and with fibres ( 4 ) in order to generate a material mixture ( 5 ), wherein the fibres ( 4 ) have a lower melting point and/or a lower chemical resistance than the base material ( 2 ); moulding a moulded body ( 6 ) from the material mixture ( 5 ); debinding the binding agent ( 3 ) from the moulded body ( 6 ); removing at least one portion of the fibres ( 4 ) from the moulded body ( 6 ); and sintering the moulded body ( 6 ). The invention also relates to a fuel cell having a current collector ( 1 ) that is produced by means of a method according to the invention.

First claim

The invention claimed is:

1. A method for producing a current collector ( 1 ) for a fuel cell, the method having the steps of:
mixing a pulverulent or granular base material ( 2 ) with a binder ( 3 ) and with fibers ( 4 ) to produce a material mixture ( 5 ), wherein the fibers ( 4 ) have a lower melting point than the base material ( 2 ),
shaping a shaped article ( 6 ) from the material mixture ( 5 ),
removing the binder ( 3 ) from the shaped article ( 6 ),
removing at least some of the fibers ( 4 ) from the shaped article ( 6 ), and
sintering the shaped article ( 6 ),

characterized in that the fibers ( 4 ) are admixed and comprise a fibrous material, and the binder ( 3 ) is admixed and has at least two components, wherein at least one of the two components of the binder ( 3 ) comprises a binder material, wherein the fibrous material has a melting point which corresponds or at least substantially corresponds to a melting point of the binder material.

2. The method as claimed in claim 1 , characterized in that the shaping is performed by means of sinter pressing and/or injection molding and/or a doctor blade and/or a 3D printing method.

3. The method as claimed in claim 1 , characterized in that the fibers ( 4 ) have a fiber length of between 5 mm and 100 mm.

4. The method as claimed in claim 1 , characterized in that a binder comprising at least two components is mixed as the binder ( 3 ), wherein a polymer is used as the first component of the binder ( 3 ) and a wax is used as the second component of the binder ( 3 ).

5. The method as claimed in claim 1 , characterized in that the binder ( 3 ) and/or the fibers ( 4 ) is/are removed at a temperature of between 500° C. and 700° C.

6. The method as claimed in claim 1 , characterized in that the binder ( 3 ) and/or the fibers ( 4 ) is/are removed using a solvent.

7. The method as claimed in claim 1 , characterized in that the shaped article ( 6 ) is shaped in strip form and, to produce a predefined shape of current collector ( 1 ), one part is separated from the strip-form shaped article ( 6 ).

8. The method as claimed in claim 1 , characterized in that the sintering takes place at a temperature of between 1100° C. and 1500° C.

9. A method for producing a fuel cell with at least one anode, at least one cathode, at least one electrolyte arranged between anode and cathode and at least one current collector, characterized in that the at least one current collector ( 1 ) is produced using the method as claimed in claim 1 .

10. The method as claimed in claim 1 , characterized in that the sintering takes place at a temperature of between 1250° C. and 1350° C.

11. The method as claimed in claim 1 , characterized in that the fibers ( 4 ) have both a lower melting point and a lower chemical resistance than the base material ( 2 ).

12. A method for producing a current collector ( 1 ) for a fuel cell, the method having the steps of:
mixing a pulverulent or granular base material ( 2 ) with a binder ( 3 ) and with fibers ( 4 ) to produce a material mixture ( 5 ), wherein the fibers ( 4 ) have a lower melting point than the base material ( 2 ),
shaping a shaped article ( 6 ) from the material mixture ( 5 ),
removing the binder ( 3 ) from the shaped article ( 6 ),
removing at least some of the fibers ( 4 ) from the shaped article ( 6 ), and
sintering the shaped article ( 6 ), characterized in that a binder comprising at least two components is mixed as the binder ( 3 ), wherein a polymer is used as the first component of the binder ( 3 ) and a wax is used as the second component of the binder ( 3 ).

13. A method for producing a current collector ( 1 ) for a fuel cell, the method having the steps of:
mixing a pulverulent or granular base material ( 2 ) with a binder ( 3 ) and with fibers ( 4 ) to produce a material mixture ( 5 ), wherein the fibers ( 4 ) have a lower chemical resistance than the base material ( 2 ),
shaping a shaped article ( 6 ) from the material mixture ( 5 ),
removing the binder ( 3 ) from the shaped article ( 6 ),
removing at least some of the fibers ( 4 ) from the shaped article ( 6 ), and
sintering the shaped article ( 6 ),

characterized in that the fibers ( 4 ) are admixed and comprise a fibrous material, and the binder ( 3 ) is admixed and has at least two components, wherein at least one of the two components of the binder ( 3 ) comprises a binder material, wherein the fibrous material has the same polarity as the binder material.

14. A method for producing a current collector ( 1 ) for a fuel cell, the method having the steps of:
mixing a pulverulent or granular base material ( 2 ) with a binder ( 3 ) and with fibers ( 4 ) to produce a material mixture ( 5 ), wherein the fibers ( 4 ) have a lower chemical resistance than the base material ( 2 ),
shaping a shaped article ( 6 ) from the material mixture ( 5 ),
removing the binder ( 3 ) from the shaped article ( 6 ),
removing at least some of the fibers ( 4 ) from the shaped article ( 6 ), and
sintering the shaped article ( 6 ),

characterized in that a binder comprising at least two components is mixed as the binder ( 3 ), wherein a polymer is used as the first component of the binder ( 3 ) and a wax is used as the second component of the binder ( 3 ).

15. The method as claimed in claim 14 , characterized in that a binder comprising at least two components is mixed as the binder ( 3 ), wherein a polymer is used as the first component of the binder ( 3 ) and a wax is used as the second component of the binder ( 3 ).

Assignees

• Bosch Gmbh Robert

Inventors

• Burghardt Andreas
• Huber Arne
• Simon Daniel
• Burghaus Jens
• Oberle Juergen
• Pieper Witold
• Smirnov Maxim

Classifications

• H01M8/0202

  Collectors; Separators, e.g. bipolar separators; Interconnectors · CPC title

• Y02E60/50

  Fuel cells · CPC title

• H01M8/0245

  in the form of layered or coated products · CPC title

• H01M8/0239

  Organic resins; Organic polymers · CPC title

• H01M8/0232 Primary

  Metals or alloys · CPC title