Fuel cell stack having bipolar plates, and fuel cell system

Patent metadata

Field	Value
Publication number	US-2018331374-A1
Application number	US-201615775803-A
Country	US
Kind code	A1
Filing date	Nov 14, 2016
Priority date	Nov 16, 2015
Publication date	Nov 15, 2018
Grant date	—

Abstract

The subject matter of the invention is also a fuel cell system that has a fuel cell stack according to the invention.

First claim

1 . A fuel cell stack comprising:
gas diffusion layers; and bipolar plates, each bipolar plate including:
an impermeable first dividing plate; and
two profiled dividing plates, each profiled dividing plate having:
an active area,
two distribution areas, each distribution area including two main gas ports for supply and removal of reaction gases from the active area, and a coolant main port for supply of coolant to the active area and removal of coolant from the active area, and
a second main gas port provided in one of the two distribution areas, wherein:

the profiled dividing plates are formed and arranged one over the other such that the respective bipolar plate has separate channels for the reaction gases and the coolant that connect the main gas ports for the reaction gases and the coolant main port of the two distribution areas to each other, the channels for the reaction gases in the active area are each bounded by a surface of one of the profiled dividing plates and a surface of the gas diffusion layer, a first one of the channels for the reaction gas in an inlet area of the active area has the impermeable first dividing plate that separates and divides the first one of the channels for the reaction gas into two volume regions and extends in a flow direction, wherein only one volume region of the first one of the channels for the reaction gas is adjacent to the gas diffusion layer, the second main gas port is provided next to a first one of the two main gas ports in the distribution area to supply the reaction gas to the first one of the channels, one of the two volume regions that is adjacent to the gas diffusion layer is connected to the first one of the two main gas ports, and a second one of the two volume regions that is not adjacent to the gas diffusion layer is connected to a second one of the two main gas ports.

2 . The fuel cell stack according to claim 1 , further comprising a plurality of impermeable dividing plates that are arranged downstream of the impermeable first dividing plate in the first one of the channels, wherein the impermeable dividing plates are arranged to be spaced apart from each other.

3 . The fuel cell stack according to claim 2 , wherein starting from the inlet area of the first one of the channels, each successive impermeable dividing plate after the impermeable first dividing plate has a lesser length than the respective preceding impermeable dividing plate.

4 . The fuel cell stack according to claim 1 , wherein the impermeable first dividing plate runs parallel to the gas diffusion layer.

5 . The fuel cell stack according to claim 1 , wherein the volume regions established by the impermeable first dividing plate are designed to permit an equal flow volume of reaction gas.

6 . The fuel cell stack according to claim 1 , wherein the channels run in a straight line.

7 . The fuel cell stack according to claim 1 , wherein a second one of the channels for reaction gases has an impermeable first dividing plate in the inlet area of the active area that separates and divides the second one of the channels into two volume regions and extends in the flow direction, wherein only one volume region of the second one of the channels is adjacent to the gas diffusion layer,
a second main gas port is provided next to a first one of two main gas ports in the distribution area to supply the reaction gas to the second one of the channels, one of the two volume regions that is adjacent to the gas diffusion layer is connected to the first one of the two main gas ports, and a second one of the two volume regions that is not adjacent to the gas diffusion layer is connected to a second one of the two main gas ports.

8 . The fuel cell stack according to claim 1 , wherein the fuel cell stack includes polymer-electrolyte membranes.

9 . A fuel cell system comprising:
a fuel cell stack, the fuel cell stack including: gas diffusion layers; and bipolar plates, each bipolar plate including:
an impermeable first dividing plate; and
two profiled dividing plates, each profiled dividing plate having:
an active area,
two distribution areas, each distribution area including two main gas ports for supply and removal of reaction gases from the active area, and a coolant main port for supply of coolant to the active area and removal of coolant from the active area, and
a second main gas port provided in one of the two distribution areas, wherein:

the profiled dividing plates are formed and arranged one over the other such that the respective bipolar plate has separate channels for the reaction gases and the coolant that connect the main gas ports for the reaction gases and the coolant main port of the two distribution areas to each other, the channels for the reaction gases in the active area are each bounded by a surface of one of the profiled dividing plates and a surface of the gas diffusion layer, a first one of the channels for the reaction gas in an inlet area of the active area has the impermeable first dividing plate that separates and divides the first one of the channels for the reaction gas into two volume regions and extends in a flow direction, wherein only one volume region of the first one of the channels for the reaction gas is adjacent to the gas diffusion layer, the second main gas port is provided next to a first one of the two main gas ports in the distribution area to supply the reaction gas to the first one of the channels, one of the two volume regions that is adjacent to the gas diffusion layer is connected to the first one of the two main gas ports, and a second one of the two volume regions that is not adjacent to the gas diffusion layer is connected to a second one of the two main gas ports.

10 . The fuel cell system according to claim 9 , comprising at least one humidifier that is configured to humidify a portion of at least one reaction gas.

11 . The fuel cell system according to claim 9 , wherein the impermeable first dividing plate runs parallel to the gas diffusion layer.

12 . The fuel cell system according to claim 9 , wherein the volume regions established by the impermeable first dividing plate are designed to permit an equal flow volume of reaction gas.

13 . The fuel cell system according to claim 9 , wherein the channels run in a straight line.

14 . The fuel cell system according to claim 9 , further comprising a plurality of impermeable dividing plates that are arranged downstream of the impermeable first dividing plate in the first one of the channels, wherein the impermeable dividing plates are arranged to be spaced apart from each other.

15 . The fuel cell system according to claim 14 , wherein starting from the inlet area of the first one of the channels, each successive impermeable dividing plate after the impermeable first dividing plate has a lesser length than the respective preceding impermeable dividing plate.

Assignees

• Volkswagen Ag
• Audi Ag

Inventors

• Scholz Hannes
• Brinkmeier Jan-Philipp
• Grundei Daniel
• Lucas Christian
• Schlitzberger Christian

Classifications

• H01M8/0265 Primary

  the reactant or coolant channels having varying cross sections · CPC title

• H01M2008/1095

  Fuel cells with polymeric electrolytes · CPC title

• H01M8/04291

  Arrangements for managing water in solid electrolyte fuel cell systems (H01M8/04119 takes precedence) · CPC title

• H01M8/04126

  Humidifying · CPC title

• H01M8/0258 Primary

  characterised by the configuration of channels, e.g. by the flow field of the reactant or coolant · CPC title