Bipolar plate and fuel cell

Patent metadata

Field	Value
Publication number	US-2023253577-A1
Application number	US-202318165110-A
Country	US
Kind code	A1
Filing date	Feb 6, 2023
Priority date	Feb 7, 2022
Publication date	Aug 10, 2023
Grant date	—

Abstract

A bipolar plate having an anode plate and a cathode plate and a contact surface between the two surfaces. In a transition region, at least one first groove ends and/or a second groove ends or at least one first groove merges into a second groove, wherein the grooves guide fluid. In at least one of the first grooves and second grooves, the groove base rises such that the distance of the groove base from the contact surface decreases.

First claim

1 . A bipolar plate having an anode plate and a cathode plate of which a respective one of their surfaces are arranged adjacent to one another forming a contact surface between the two surfaces,
wherein hollow spaces are formed between the two plates as a distribution region, a collection region, and a flow region arranged between the distribution region and the collection region to guide the coolant; wherein the flow region in each of the plates has a first group of first grooves that are arranged transversely to their longitudinal directions adjacent to one another and separated from one another by first webs to guide the coolant in the first grooves; wherein the distribution region and the collection region in each of the plates each have a second group of second grooves that are arranged transversely to their longitudinal directions adjacent to one another and separated from one another by second webs to guide the coolant in the first grooves, and having a transition region in which at least one first groove ends and/or a second groove ends or at least one first groove merges into a second groove, wherein, for at least one of the first grooves and second grooves, the groove base rises, starting in the flow region, in the distribution region, and/or in the collection region, in the direction of the transition region and/or in the transition region such that the distance of the groove base from the contact surface decreases.

2 . The bipolar plate in accordance with claim 1 , wherein at least one of the first grooves and second grooves ends in the transition region.

3 . The bipolar plate in accordance with claim 1 , wherein at least one of the second grooves merges into a first groove at its end in the transition region.

4 . The bipolar plate in accordance with claim 1 , wherein, at least for one of the first grooves and second grooves, the groove base rises over a length L1, with L1 amounting to at least 1 mm.

5 . The bipolar plate in accordance with claim 4 , wherein, at least for one of the first grooves and second grooves, the groove has a width B to which L1≥B applies, where the width B is determined at half depth of the groove.

6 . The bipolar plate in accordance with claim 1 , wherein, at least for one of the first grooves and second grooves, the rise of the groove base is linear over a length L2; and/or in that in the rise of the groove base the plane of the groove base with the plane of the contact surface directly at both sides of the groove, at least sectionally, forms an angle α with α≤10°.

7 . The bipolar plate in accordance with claim 1 , wherein, for at least one of the first grooves and second grooves that end in the transition region, the groove has a first curvature region having a radius R1 in which the groove base merges into the groove wall and a second curvature region having the radius R2 in which the groove wall merges into the regions adjacent to the groove of the respective associated plate, in the cross-section perpendicular to its longitudinal extent along the rise of the groove base and measured on the inner side of the groove.

8 . The bipolar plate in accordance with claim 7 , wherein the first curvature region and the second curvature region are spaced apart from one another by an intermediate region of the groove wall.

9 . The bipolar plate in accordance with claim 7 , wherein the radius R1 is at least regionally constant in the longitudinal extent of the groove along the rise of the groove base; and/or the radius R2 is at least regionally constant in the longitudinal extent of the rise of the groove base.

10 . The bipolar plate in accordance with claim 7 , wherein the radius R1 is at least regionally constant in the longitudinal extent of the groove along the rise of the groove base; and/or the radius R2 is at least regionally constant in the longitudinal extent of the rise of the groove base, and wherein 0.04 mm≤R1≤0.30 mm and/or 0.11 mm≤R2≤0.33 mm.

11 . The bipolar plate in accordance with claim 7 , wherein the radius R1 is at least regionally constant in the longitudinal extent of the groove along the rise of the groove base; and/or the radius R2 is at least regionally constant in the longitudinal extent of the rise of the groove base, and wherein the radius of the plate is substantially equal to the radius R1 in a region of one of the two surfaces of the plate disposed opposite the surface having the radius R2 at the outer side with respect to the groove.

12 . The bipolar plate in accordance with claim 1 , wherein at least one of the first grooves or second grooves that merge at their end in the transition region into a second groove or a first groove, has a fifth curvature region having a radius R1′ in which the groove base merges into the groove wall, and a sixth curvature region having the radius R2′ in which the groove wall merges into the regions of the plate adjacent to the groove, in cross-section perpendicular to the longitudinal extent along the rise of the groove base and measured on the inner side of the groove; and
wherein the radius R1′ is at least regionally constant in the longitudinal extent of the groove along the rise of the groove base; and/or the radius R2′ is at least regionally constant in the longitudinal extent of the rise of the groove base.

13 . The bipolar plate in accordance with claim 12 , characterized by 0.225 mm≤R1′≤0.375 mm and/or 0.125 mm≤R2′≤0.215 mm.

14 . The bipolar plate in accordance with claim 12 , wherein the radius of the plate is substantially equal to the radius R1′ in a region of one of the surfaces of the plate disposed opposite the surface having the radius R2′ at the outer side with respect to the groove.

15 . The bipolar plate in accordance with claim 1 , wherein at least one of the first grooves and second grooves that end in the transition region at its end has a third curvature region having a radius R3 in which the groove base merges into the groove wall in a cross-section along its longitudinal extent and measured on the inner side of the groove.

16 . The bipolar plate in accordance with claim 15 , characterized by 0.24 mm≤R3≤1.5 mm.

17 . A fuel cell having one or more bipolar plates in accordance with claim 1 .

Assignees

• Reinz Dichtungs Gmbh

Inventors

• Blersch Robert
• Glueck Rainer
• Gruenwald Bernadette
• Kunz Claudia

Classifications

• H01M8/0258 Primary

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

• H01M8/0265

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

• H01M8/026 Primary

  characterised by grooves, e.g. their pitch or depth · CPC title

• H01M8/0267

  having heating or cooling means, e.g. heaters or coolant flow channels · CPC title

• Y02E60/50

  Fuel cells · CPC title