DE102019216264A1 - Production method for producing a guiding device for guiding at least one fluid, as well as production method for producing a fuel cell unit - Google Patents

Abstract

The invention relates to a manufacturing method (100) for manufacturing a guiding device (2) for guiding at least one fluid (200) for at least one fuel cell (4), comprising the following steps: Manufacturing (101) a guiding element (11) with a channel structure (12) for guiding the fluid (200), - arranging (102) a cover element (13) for covering the channel structure (12) on the guide element (11) so that the guide element (11) and the cover element (13) have a guide unit (10) for The invention also relates to a method for producing a fuel cell unit (1).

Description

The invention relates to a manufacturing method for manufacturing a guiding device for guiding at least one fluid for at least one fuel cell, as well as a manufacturing method for manufacturing a fuel cell unit with a plurality of fuel cells.

State of the art

Guiding devices for guiding fluids in fuel cells are known in principle from the prior art. For example, membrane electrode units, so-called MEAs, with guide devices are arranged alternately in a fuel cell stack. A frequently used form of such guide devices is a bipolar plate. Bipolar plates serve as an electrical connection between neighboring cells and have an electrode that serves as a current collector. Furthermore, through an at least double-walled construction and corresponding channel structures, bipolar plates offer the possibility of air and hydrogen flowing on the sides of the MEAs, while water cooling is provided in between.

In known manufacturing processes for bipolar plates, the channel structures are usually milled in order to achieve the highest possible accuracy. However, this is time consuming and expensive. Alternatively, it is known to produce all geometric elements, such as the channel structure, an inflow area and receptacles for seals, in one forming step by plastic deformation of a blank. Due to the process, this can lead to a strong stretching of the thin sheets used, which limits the geometrical ratios that can be achieved, such as width to depth, of the channels and makes it difficult or impossible to use pre-coated material. For example, from the DE 10 2006 041 296 A1 a forming of a sheet metal known in order to predetermine channels. The production of the connection for introducing fluid into the channels can be improved.

Disclosure of the invention

• - Fertigen eines Leitelementes mit einer Kanalstruktur zum Führen des Fluides, insbesondere wobei mehrere oder alle Kanäle der Kanalstruktur einzeln gefertigt werden,
• - Anordnen eines Abdeckelementes zum Abdecken der Kanalstruktur an dem Leitelement, sodass das Leitelement und das Abdeckelement eine Leiteinheit zum Leiten des Fluides bilden,
• - Anformen einer Anschlussschnittstelle an die Leiteinheit für einen Zugang zur Kanalstruktur zwischen dem Leitelement und dem Abdeckelement für das Fluid, insbesondere wobei das Anformen einer Anschlussschnittstelle nach dem Anordnen des Abdeckelementes durchgeführt wird.

According to a first aspect of the invention, a production method for producing a guide device for guiding at least one fluid for at least one fuel cell is provided. The manufacturing process includes the following steps:

• - Manufacturing a guide element with a channel structure for guiding the fluid, in particular wherein several or all channels of the channel structure are manufactured individually,
• - Arranging a cover element for covering the channel structure on the guide element, so that the guide element and the cover element form a guide unit for guiding the fluid,
• Forming a connection interface on the guide unit for access to the channel structure between the guide element and the cover element for the fluid, in particular wherein the connection interface is molded after the cover element has been arranged.

The guide device can thus be designed in a multilayered and / or plate-like manner. The guide device is preferably a bipolar plate which can be arranged between two membrane-electrode units in a fuel cell unit. The fluid can be a fuel gas, in particular air and / or hydrogen, or a coolant for cooling the at least one fuel cell. A plurality of fluids can preferably be guided through the channel structure. For example, the guide device for guiding the coolant between the guide element and the cover element can be formed in the channel structure. Furthermore, it is conceivable that air can be guided on a side of the cover element facing away from the guide element and hydrogen or another fuel can be guided on the side of the guide element remote from the cover element. Thus, preferably three different fluids can be passed through the guide device. In particular, the guide element can have a channel structure on both sides. The channel structure is preferably embossed when the guide element is manufactured, so that the guide element has channels on both sides. The access for the fluid can be understood to mean an inlet and / or an outlet via which the fluid can be introduced into the channel structure between the guide element and the cover element or from which the fluid can be discharged from the channel structure.

The guide element can have an electrically conductive material in order to be able to be used as an electrode, in particular as a current collector, in the fuel cell. For example, the guide element can have a metal and / or an electrically conductive plastic. Furthermore, it can be provided that the guide element comprises an electrically conductive connection. The guide element can be made in one piece or in several pieces. For example, it is conceivable that several sections of the guide element are manufactured individually and then attached to one another. The guide element is preferably a one-piece component.

The cover element can be, for example, a cover that closes the channel structure in the assembled state. The cover element can be designed in the manner of a plate, in particular as a sheet metal part or as a plastic plate. Thus, the channel structure can only be achieved through the Guide element be given. Alternatively, it is conceivable that the cover element also has a channel structure which is combined with the channel structure of the guide element in order to design the finished channels of the guide device.

When the connection interface is molded onto the guide unit, the connection interface is preferably cohesively connected to the guide element and / or the cover element. In particular, the connection interface can be given its geometric shape when it is molded onto the guide unit. The connection interface can have a channel inlet or a plurality of channel inlets through which or through which the fluid can be introduced into the channel structure. In particular, the connection interface can be designed for connection to a fluid system.

Thus, the above disadvantages known from the prior art are at least partially eliminated. In particular, the production of a guiding device for guiding a fluid for at least one fuel cell is simplified in a cost-effective manner. Further features and details of the invention emerge from the respective subclaims, the description and the drawings.

By shaping the connection interface, it can be avoided that the process-related stretching of the guide element occurs. As a result, improved geometrical relationships, such as width to depth, can be achieved in a limited manner by channels of the channel structure. Furthermore, this can make it possible for the guide element to have a pre-coated material. Furthermore, the manufacture of the guide element for series production can be improved.

Furthermore, in a production method according to the invention, it can advantageously be provided that the channel structure is produced during production of the guide element by a multi-stage reshaping process of a plate-shaped raw element. The raw element can be a sheet metal or a plastic plate, for example. During the forming process, the raw element can be plastically deformed in order to obtain the channel structure. In particular, the channel structure can be embossed into the raw element in order to form the channel structure on both sides of the guide element. By reshaping in several stages, stretching of the guide element can be reduced. It can thus be provided that a channel is partially or completely formed with each stage of the forming process. In particular, the multi-stage forming process can include a progressive composite process and / or a lamellar rolling process.

• - Niederhalten des Rohelementes durch das erste Werkzeugelement,
• - Umformen des Rohelementes durch das zweite Werkzeugelement

während das erste Werkzeugelement das Rohelement niederhält.Furthermore, in a manufacturing method according to the invention, it can advantageously be provided that the multi-stage forming process, in particular for several or all channels of the channel structure individually, is carried out by at least a first and a second tool element, the manufacturing method comprising the following steps:

• - Holding down the raw element by the first tool element,
• - Reshaping of the raw element by the second tool element

while the first tool element holds down the raw element.

For example, the first tool element can be a hold-down device by means of which the raw element is fixed at least in sections in order to simplify and / or enable the deformation of a further section by the second tool element. It is conceivable that the raw element is pressed by the first tool element onto a further tool element, in particular in the form of a die. The second tool element can be designed in the form of a punch, for example in order to form a channel of the channel structure in the raw element. By holding down the raw element, stretching is at least partially prevented. Furthermore, through the use of the two tool elements, efficient series production can be made possible, in which, for example, a raw element is reshaped in the form of a strip material. In particular, the strip material can be cut or cut to size by a cutting tool for the guide element.

Furthermore, in a manufacturing method according to the invention, it can advantageously be provided that the raw element is moved in the multi-stage forming process along a manufacturing direction, in particular by a channel width of the channel structure, the first tool element being arranged downstream of the second tool element in the manufacturing direction and / or that a reshaping of the second tool element formed form structure is carried out by the first tool element. As a result of the movement in the manufacturing direction, the raw element can be conveyed further, so that holding down and / or reshaping by the first and / or second tool element can be carried out by a lifting movement of the first or second tool element. As a result of the post-shaping, the channel structure can be formed with increased accuracy and / or with finer geometries. For example, the raw element can be preformed by the second tool element. The first tool element can then be used, for example, for radii and / or more Geometry elements are molded. For example, perforations through the first tool element are also conceivable.

• - Anformen eines Dichtelementes an die Leiteinheit.

Furthermore, in a manufacturing method according to the invention, it can advantageously be provided that the manufacturing method comprises the following step:

• - Forming a sealing element on the guide unit.

When the sealing element is molded onto the guide unit, the sealing element can be materially connected to the cover element and / or the guide element. In particular, the sealing element can be given the geometric shape when the sealing element is molded onto the guide unit. The sealing element can comprise a plastic, in particular in the form of an elastomer. In particular, the guide unit can be sealed in a gas-tight manner at least in some areas by the sealing element. In particular, the guide element can be arranged offset to the cover element, so that a gap is created in which an injection molding tool can be inserted for molding the sealing element. Furthermore, it is conceivable that the molding of the sealing element is carried out at the same time as the molding of the connection interface, in particular if the sealing element and the connection interface are made of the same material.

In a manufacturing method according to the invention, it is also conceivable that the molding of the connection interface and / or the molding of the sealing element comprises a multi-component plastic injection molding. For example, the multi-component plastic injection molding and the forming process for manufacturing the channel structure can be carried out in one tool unit. As a result, the manufacturing process can be simplified overall, in that the manufacturing process is spatially limited. As a result, time for manufacturing the guide device can also be saved. A first plastic component can preferably be molded onto the guide unit for molding the connection interface and a second plastic component for molding the sealing element. The multi-component plastic injection molding can thus be a two-component plastic injection molding. In particular, when the connection interface is molded and when the sealing element is molded, the connection interface, the sealing element and the guide unit are connected to one another in a materially bonded manner.

It is also conceivable in a manufacturing method according to the invention that at least one mounting element for mounting the guide unit and / or the guide device in a fuel cell system is molded onto the guide unit when the connection interface is molded and / or the sealing element is molded onto it. The mounting element is preferably made of the same material with the connection interface and / or the sealing element. In this way, at least one further geometric element can be produced in a cost-effective manner, in particular without the need for an additional production station. By means of the assembly element, the guide device can be prepared for assembly in a fuel cell stack, so that subsequent production steps for the production of a fuel cell unit are also simplified by the molding of the assembly element. The mounting element can, for example, comprise a clip connector or fixings for a cell structure of the fuel cell. A plurality of assembly elements can preferably be formed onto the guide unit when the connection interface is molded and / or when the sealing element is molded.

Furthermore, in a manufacturing method according to the invention, it can advantageously be provided that the cover element is connected to the guide element in a materially and / or electrically conductive manner when it is arranged on the guide element. For example, the cover element and the guide element can be welded or soldered to one another in order to produce a cohesive and electrically conductive connection. This can reduce the electrical resistance of the guide unit, e.g. if the guide unit is designed as an electrode of at least one fuel cell or two adjacent fuel cells.

Furthermore, in a manufacturing method according to the invention, it can advantageously be provided that the cover element has a limiting means for guiding a further fluid on a side of the cover element facing away from the guide element. The limiting means can, for example, comprise a raised edge in order to guide the further fluid.

In particular, a crossflow of reaction gases can be made possible by the limiting means. The delimitation means can be produced by a forming process, e.g. by bending the cover element, or can be molded onto a particularly flat section of the cover element by means of a plastic injection molding process.

According to a further aspect of the invention, a production method for producing a fuel cell unit with a plurality of fuel cells is provided. Several fuel cell elements are provided, each of which is arranged between two guide devices. Furthermore, the guide devices are manufactured beforehand using a manufacturing method according to the invention.

A production method according to the invention thus brings the same advantages as have already been described in detail with reference to a production method according to the invention. By arranging the fuel cell elements between two guide devices, in particular a fuel cell stack is thus formed. This preferably results in an alternating arrangement of guide devices and fuel cell elements. A fuel cell element can, for example, comprise a membrane-electrode unit.

• 1 ein erfindungsgemäßes Herstellverfahren zum Herstellen einer Leitvorrichtung in schematischer Darstellung der Verfahrensschritte,
• 2 ein Fertigen eines Leitelementes bei dem erfindungsgemäßen Herstellverfahren,
• 3 das Leitelement nach einem Einbringen einer Kanalstruktur,
• 4 eine Leiteinheit,
• 5-7 Detailansichten der nach dem Herstellverfahren hergestellten Leitvorrichtu ng,
• 8 eine nach einem erfindungsgemäßen Produktionsverfahren produzierte Brennstoffzelleneinheit.

Further advantages, features and details of the invention emerge from the following description, in which exemplary embodiments of the invention are described in detail with reference to the drawings. The features mentioned in the claims and in the description can be essential to the invention individually or in any combination. They show schematically:

• 1 a manufacturing method according to the invention for manufacturing a guide device in a schematic representation of the method steps,
• 2 a production of a guide element in the production method according to the invention,
• 3 the guide element after a channel structure has been introduced,
• 4th a management unit,
• 5-7 Detailed views of the guide device manufactured according to the manufacturing process,
• 8th a fuel cell unit produced by a production method according to the invention.

In the following description of some exemplary embodiments of the invention, identical reference symbols are used for the same technical features in different exemplary embodiments.

1 shows a manufacturing process according to the invention 100 for producing a guide device 2 for conducting at least one fluid 200 . There is also a manufacturing process 101 of a guide element 11 with a channel structure 12th for guiding the fluid 200 intended. The manufacturing 101 of the guide element 11 includes a multi-stage forming process 110 of a plate-shaped raw element 30th who is in 2 is shown.

2 shows different stages of the forming process 110 . The raw element 30th can be provided as a plate and / or strip-shaped flat material. To the channel structure 12th into the raw element 30th To shape is like holding down 111 of the raw element 30th by a first tool element 31 intended. Forming takes place at the same time 112 of the raw element 30th by the second tool element 32 while the first tool element 31 the raw element 30th holds down. In particular, another tool element 35 be provided in the form of a hold-down device, so that the raw element 30th during forming 112 is held down on at least two sides. This can result in a flow of material during forming 112 prevented or reduced. A counter tool is preferred 34 provided in the form of a die to the tool elements 31 , 32 , 35 counteract and the raw element 30th to support. After forming 112 of the raw element 30th , becomes the raw element 30th along a manufacturing direction 113 by a channel width of the channel structure 12th emotional. The first tool element is preferably 31 the second tool element 32 in the direction of manufacture 113 subordinate. This allows for reshaping 114 of the raw element 30th respectively. In this case, one can advantageously be carried out by the second tool element 32 shaped shape structure 33 further deformed in order to be able to form detailed geometries. So can when reshaping 114 eg smaller radii can be formed without the raw element 30th when forming 112 to damage.

3 shows the guide element 11 with the channel structure 12th . Here is the channel structure 12th formed on both sides, so that at least two fluids 200 , 202 through the channel structure 12th can be guided. In particular, a separating process, in particular with a contoured cut, can then be carried out in order to create a plurality of guide elements 11 to be obtained from a strip material.

An arrangement then takes place 102 a cover element 13th on the guide element 11 . This becomes the guiding element 11 through the cover element 13th covered so that the cover 13th and the guide element 11 a lead unit 10 for guiding the fluid 200 form, as in 4th shown. Preferably, the guide element 11 and the cover element 13th cohesively and / or electrically connected to one another. For example, the guide element 11 and the cover element 13th be welded or soldered. This can create an electrical resistance in the guide unit 10 be reduced. The cover element 13th also points to the guide element 11 facing away from a limiting means 17th for guiding another fluid 202 , for example in the form of air.

After arranging 102 of the cover element 13th a molding takes place 103 a connection interface 15th for introducing the fluid 200 to the control unit 10 . In the 5 to 7th are detailed views of the resulting guide device 2 shown. 5 shows an area of a first page 2.1 the guiding device 2 . In particular, represents the view shown shows an end region of the guide device 2 The connection interface is 15th shown at which an access for the fluid 200 the channel structure 12th of the guide element 11 is created through which the fluid 200 the channel structure 12th between the guide element 11 and the cover element 13th can be supplied or discharged. Preferably, the guide device 2 be designed symmetrically, so that a connection interface at one end region 15th for supplying the fluid 200 and at the opposite end region of the guide device 2 a connection interface 15th to divert the fluid 200 is trained. When molding 103 the connection interface 15th are also a mounting element 16 for mounting the guide unit 10 in a fuel cell system 1 to the control unit 10 molded. This can be, for example, openings for a screw connection. In particular, the mounting elements 16 the same material as the connection interface 15th educated. Furthermore, a molding 104 a sealing element 14th respectively. The 6th and 7th show the sealing element 14th than to the lead unit 10 circumferential seal. Preferably, the molding 103 the connection interface 15th and molding 104 of the sealing element 14th take place in a two- or multi-component plastic injection molding. Furthermore shows 6th that when molding 103 the connection interface 15th the channel structure 12th also partly through a seal 14.1 can be sealed to allow an inflow of a second fluid 201 on a second page 2.2 the guiding device 2 into the channel structure 12th to prevent.

8th Fig. 13 is a partial view of a fuel cell unit 1 which was produced by a production method according to the invention. The fuel cell unit 1 has multiple fuel cell elements 3 on, each between two guide devices 2 were ordered. Preferably the guiding devices are 2 according to a manufacturing process described above 100 produced. This results in a fuel cell stack in which guide devices alternate 2 and fuel cell elements 3 are arranged next to each other. Each of the guiding devices 2 of three fluids 200 , 201 , 202 be flowed against. For example, it can be a fluid 200 , which is a channel structure 12th the guiding device 2 via a connection interface 15th A coolant flows through the center. Furthermore, the channel structure 12th on the opposite side of the guide element 11 by another fluid 201 , for example in the form of hydrogen. The cover element 13th can flow against the guiding device 2 by another fluid 202 , for example in the form of air. This allows the fuel cell unit 1 be efficiently operable.

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• DE 102006041296 A1 [0003]

Claims (10)

Manufacturing method (100) for manufacturing a guiding device (2) for guiding at least one fluid (200) for at least one fuel cell (4), comprising the following steps: - Manufacturing (101) a guide element (11) with a channel structure (12) for guiding the fluid (200), - Arranging (102) a cover element (13) for covering the channel structure (12) on the guide element (11), so that the guide element (11) and the cover element (13) form a guide unit (10) for guiding the fluid (200), - Shaping (103) a connection interface (15) on the guide unit (10) for access to the channel structure (12) between the guide element (11) and the cover element (13) for the fluid (200). Manufacturing process (100) Claim 1 , characterized in that the channel structure (12) is produced during the manufacture (101) of the guide element (11) by a multi-stage forming process (101.1) of a plate-shaped raw element (30). Manufacturing process (100) Claim 2 , characterized in that the multi-stage forming process (110) is carried out by at least a first and a second tool element (31, 32), the manufacturing method (100) comprising the following steps: holding down (111) the raw element (30) by the first Tool element (31) - Reshaping (112) of the raw element (30) by the second tool element (32) while the first tool element (31) holds down the raw element (30). Manufacturing process (100) Claim 3 , characterized in that the raw element (30) is moved in the multi-stage forming process (110) along a manufacturing direction (113), wherein the first tool element (31) is arranged downstream of the second tool element (32) in the manufacturing direction (113) and / or that a reshaping (114) of a shaped structure (33) formed by the second tool element (32) takes place by the first tool element (31). Manufacturing method (100) according to one of the preceding claims, characterized in that the manufacturing method (100) comprises the following step: - molding (104) a sealing element (14) onto the guide unit (10). Manufacturing method (100) according to one of the preceding claims, characterized in that the molding (103) of the connection interface (15) and / or the molding (104) of the sealing element (14) comprises a multi-component plastic injection molding. Manufacturing method (100) according to one of the preceding claims, characterized in that when molding (103) the connection interface (15) and / or when molding (104) the sealing element (14) at least one mounting element (16) for mounting the guide unit (10) is molded onto the guide unit (10) in a fuel cell system (1). Manufacturing method (100) according to one of the preceding claims, characterized in that the cover element (13) is materially and / or electrically conductively connected to the guide element (11) when it is arranged (103) on the guide element (11). Manufacturing method (100) according to one of the preceding claims, characterized in that the cover element (13) has a limiting means (17) for guiding a further fluid (202) on a side of the cover element (13) facing away from the guide element (11). Production method for producing a fuel cell unit (1) with a plurality of fuel cells (4), a plurality of fuel cell elements (3) being provided, which are each arranged between two guide devices (2), characterized in that the guide devices (2) beforehand according to a manufacturing method (100 ) can be produced according to one of the preceding claims.

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