Electrode plate for bipolar plate and bipolar plate for fuel cell stack, method for producing fuel cell stack

Abstract

The invention relates to an electrode plate, namely a cathode plate or an anode plate, for a bipolar plate (100), in particular for a fuel cell stack of a fuel cell vehicle, having a plate orientation device (110 / 120), the invention relates to a method for orienting an electrode plate (101 / 102) for assembling two electrode plates (102, 101) into a bipolar plate (100) in relation to a second electrode plate (102 / 101), which corresponds thereto and has a plate orienting device (120 / 110) thereof, said plate orienting device (110 / 120) forming, at least in part, a bipolar plate positioning device (105, 105 ') of the bipolar plate (100), and a plate orienting device (105, 105') for orienting the electrode plate (101 / 102) relative to the second electrode plate (102 / 101), which corresponds thereto and has the plate orienting device (120 / 110) thereof, when assembling the two electrode plates (102, 101) into the bipolar plate (100). 110, 120) for stacking the bipolar plate (100) in the fuel cell stack (10). The invention further relates to a method for manufacturing the fuel cell stack (10).

Description

Technical Field

[0001] The present invention relates to an electrode plate for a bipolar plate and a bipolar plate for a fuel cell stack. The present invention also relates to a method for assembling a bipolar plate and a method for stacking bipolar plates. Background Art

[0002] In a low-temperature polymer electrolyte fuel cell of a fuel cell unit (stationary or mobile), such as a fuel cell system, for example a fuel cell vehicle, two reactants of two operating media are electrochemically converted into electrical energy and heat. In this case, the fuel cell comprises at least one membrane electrode unit (MEA). Typically, the fuel cell is constructed with a plurality of membrane electrode units arranged in a stack and bipolar plates arranged between them (fuel cell stack or stack). Summary of the invention

[0003] The space on the two large-area side surfaces of a bipolar plate for a fuel cell stack is limited and therefore "precious". The object of the present invention is therefore to provide a bipolar plate whose electroactive surfaces on the cathode and / or anode side and / or its port surfaces for operating and / or cooling media can be well utilized in order to be able to provide a high-performance bipolar plate and thus a high-performance fuel cell stack.

[0004] The object of the invention is achieved by means of an electrode plate for a bipolar plate, i.e. a cathode plate and / or an anode plate, and by means of a bipolar plate for a fuel cell stack of a fuel cell, in particular for a fuel cell vehicle. Furthermore, the object of the invention is achieved by means of a method for assembling a bipolar plate and by means of a method for stacking bipolar plates into a fuel cell stack for a fuel cell, in particular for a fuel cell vehicle. Advantageous developments, additional features and / or advantages of the invention are revealed in the dependent claims and the following description.

[0005] The electrode plate according to the present invention comprises a plate orienting device for orienting the electrode plate relative to a second electrode plate corresponding thereto having a plate orienting device, for assembling the two electrode plates into a bipolar plate, wherein the plate orienting device (temporally after assembling the two electrode plates into the bipolar plate) at least partially forms an area of ​​a bipolar plate positioning device of the bipolar plate, for stacking the bipolar plates into a fuel cell stack.

[0006] That is, the plate orientation means, such as two through-notches of one electrode plate (the cathode plate or anode plate of the formed bipolar plate) and the plate orientation means of the second electrode plate, such as two corresponding through-notches (the anode plate or cathode plate of the formed bipolar plate) form a bipolar plate positioning means when they are assembled to form a bipolar plate. Then, the bipolar plate positioning means is used to position the bipolar plate when the bipolar plate is stacked with other bipolar plates to form a fuel cell stack.

[0007] The contour of the plate orientation device can be arranged in the electrode plate in such a way that it can essentially coincide with the contour of the plate orientation device of the second electrode plate for the same bipolar plate only in a point-like (regional) or section-like manner. Figures 3 to 5 ) For the assembly of bipolar plates, the two electrode plates (cathode plate and anode plate) can only be superimposed in such a way that the contours of the mutually related through-notches (orientation holes, orientation slits (see below) of the two plate orientation devices can only overlap in a point-like or regional or segmental manner. In this case, for example, the mutually related through-notches of the two electrode plates are of course arranged at least in sections to be essentially concentrically superimposed on each other.

[0008] The electrode plate may not include bipolar plate positioning means for the bipolar plate that are functionally substantially or completely independent of its plate orientation means and at least partially. That is, the plate orientation means and part of the bipolar plate positioning means (i.e. the area provided by the relevant electrode plate for the bipolar plate positioning means of the subsequent bipolar plate) are at least partially or completely integrated into each other (in the latter case, they are identical). Of course, additional orientation aids, such as orientation curling, may be provided in each electrode plate, which are substantially only used for orienting two relevant electrode plates to each other when assembled into a bipolar plate.

[0009] The plate orientation device can be arranged in the electrode plate, substantially completely in the electrode plate or only in the electrode plate. That is, the plate orientation device does not pass through the circumferential edge, especially the outer peripheral edge structure of the electrode plate, especially not in sections. The plate orientation device may include at least one notch, especially at least one through-notch in the electrode plate. The plate orientation device may include an orientation hole in the electrode plate on the one hand and an orientation slit in the electrode plate on the other hand. The orientation hole and the orientation slit may be arranged in mutually opposite longitudinal end sections of the electrode plate at intervals from each other. Preferably, the orientation hole and the orientation slit are preferably arranged in mutually opposite longitudinal end sections of the electrode plate at intervals from each other in a straight line or diagonally.

[0010] The bipolar plate according to the present invention comprises a cathode plate and an anode plate fixedly connected thereto, wherein the plate orientation device of the cathode plate and the plate orientation device of the anode plate (by means of which the cathode plate and the anode plate are mutually oriented in the bipolar plate) together at least partially form (through or between them) a bipolar plate positioning device for stacking the bipolar plate into a fuel cell stack. That is, the plate orientation device of the cathode plate and the plate orientation device of the anode plate together at least partially form a bipolar plate positioning device of the bipolar plate for stacking the bipolar plate into a fuel cell stack.

[0011] In this case, the combination of the plate orientation devices (integral) of the cathode plate and the anode plate can at least partially form the bipolar plate positioning device of the bipolar plate. Furthermore, both the cathode plate and the anode plate can have no plate orientation device that is only used to orient the cathode plate and the anode plate and the bipolar plate relative to each other. Furthermore, the bipolar plate can have no plate orientation device separate from its bipolar plate positioning device, in particular neither in sections in its cathode plate nor in sections in its anode plate; an exception here could be additional orientation aids (see above).

[0012] The cathode plate and the anode plate are fixedly arranged one on top of the other to form a bipolar plate. Here, the mutually related contours of the plate orientation devices of the cathode plate and the anode plate can be arranged so that the contour of the first plate orientation device only substantially overlaps the contour of the second plate orientation device in a point-like (regional) or segmental manner. In addition, in a top view of the bipolar plate, the contour of the first plate orientation device can be inscribed in or surround the contour of the second plate orientation device.

[0013] This relates in particular to one orientation hole each of the plate orientation devices (see below and above) or to two orientation holes (orientation holes stacked one above the other) of the bipolar plate positioning device. In this case, for example, the n-cornered (convex) circular contour of one electrode plate can be inscribed in the circular contour of the second electrode plate (of course only in top view; see Figures 3 to 5 Each left side, orientation hole). Preferably, the contour of the plate orientation device of the cathode plate (electrode plate) is at least partially "inscribed in" the contour of the plate orientation device of the anode plate (other electrode plates), or the contour of the plate orientation device of the anode plate (electrode plate) at least sectionally "surrounds" the contour of the plate orientation device of the cathode plate (other electrode plates).

[0014] In the top view of the bipolar plate, the surface of the first plate orientation device can be arranged in the bipolar plate in such a way that it only partially overlaps with the surface of the second plate orientation device. This particularly relates to one orientation slot of the plate orientation device (see below and above) or to two orientation slots (orientation slots that overlap each other) of the bipolar plate positioning device. In this case, for example, a (segment-shaped or fan-shaped) partial surface of the plate orientation device of the cathode plate (electrode plate) overlaps with a (segment-shaped or fan-shaped) partial surface of the plate orientation device of the anode plate (other electrode plate) (of course only in the top view; see Figures 3 to 5 each right side, directional seam).

[0015] The plate orientation devices of the cathode plate and the anode plate can form two plate stacking through-slots in the bipolar plate for stacking the bipolar plate into the fuel cell stack. That is, the two plate stacking through-slots at least partially constitute the bipolar plate positioning device. Not only the plate orientation device of the cathode plate but also the plate orientation device of the anode plate can include two through-slots respectively, wherein these four through-slots form two through-slots in the bipolar plate as the bipolar plate positioning device. The two through-slots in not only the cathode plate but also the anode plate can be constructed as an orientation hole and an orientation slit respectively, and these two through-slots form an orientation double hole and an orientation double slit in the bipolar plate as the bipolar plate positioning device.

[0016] The orientation holes of one plate orientation device can have only a circular contour, while the orientation holes of the other plate orientation device can have a circular contour with a protrusion. The protrusion of the circular contour is preferably located in the corner area of ​​a regular polygon. The orientation holes with only a circular contour are preferably arranged in the anode plate, while the orientation holes with a protruding circular contour are preferably arranged in the cathode plate. However, this can of course also be configured inversely.

[0017] The orientation slot of one plate orientation device can be configured as an elongated hole, while the orientation slot of the other plate orientation device can be configured as a tapered or stepped elongated hole. In the anode plate, the orientation slot is preferably arranged as an elongated hole, and in the cathode plate, the orientation slot is preferably arranged as an elongated hole that is tapered or stepped. However, this can of course also be configured in the opposite way. An orientation hole with a circular profile with a protrusion can be inscribed in an orientation hole with only a circular profile, and an orientation slot as a tapered or stepped elongated hole can be at least partially inscribed in an orientation slot as an elongated hole (of course again in the top view).

[0018] In the method according to the invention for assembling bipolar plates for a fuel cell stack, in an orientation step of the method, the cathode plate and the anode plate of the formed bipolar plate are oriented relative to one another and fixed relative to one another in a chronologically subsequent fastening step of the method, wherein in the orientation step, the cathode plate and the anode plate are oriented relative to one another by plate orientation devices for the cathode plate and the anode plate, and the plate orientation devices at least partially form bipolar plate positioning devices in the forming and formed bipolar plates for stacking the bipolar plates in the fuel cell stack. In the method for assembling bipolar plates, a preferably single cathode plate and a preferably single anode plate are respectively joined to form the relevant bipolar plate.

[0019] The plate orientation device of the cathode plate and the anode plate preferably comprises two through slots, respectively. In the orientation step, the through slots of the cathode plate and the anode plate, which are related to each other, can be arranged substantially concentrically with each other at least in sections. In addition, in the orientation step, the two through slots of the cathode plate and the anode plate, which are related to each other, can be centered with each other in the middle plane (or a plane parallel to the middle plane) by the shaped orientation auxiliary device of the plate orientation device. The shaped orientation auxiliary device for inserting through the through slot is preferably configured as an assembly pin at this time. The orientation device can include a preferred straight section with a polygonal cross section, particularly preferably a regular triangular, quadrilateral or pentagonal cross section in its central region.

[0020] Furthermore, in the orientation step, two mutually related through slots for the formed orientation aid can be constructed as an orientation hole having only a circular contour and an orientation hole having a circular contour with a protrusion. Here, in the top view, the orientation hole having a circular contour with a protrusion is inscribed in the orientation hole having only a circular contour. During centering, the formed orientation device, on the one hand, rests with its outer corners or outer edges on the protrusion with the raised circular contour inside the cathode plate / anode plate, and on the other hand, the formed orientation device rests with these outer corners or outer edges on the inside of the circular contour of the anode plate / cathode plate (see Figure 4 left side).

[0021] Furthermore, the two mutually related through-slots of the cathode plate and the anode plate can be oriented relative to each other in the middle plane by means of the plate orientation means with one or exactly one translational or rotational degree of freedom, i.e. restrained (other degrees of freedom can be conditionally realized). The preferably cylindrical or truncated cone-shaped orientation means for insertion through the through-slots is preferably designed as an assembly pin.

[0022] Furthermore, the two mutually related through-slots for the orientation means can be designed as an elongated hole as an orientation slit and as a tapered or stepped elongated hole as an orientation slit. Here, the orientation slit as a tapered or stepped elongated hole is at least partially inscribed in the orientation slit as an elongated hole in a top view. When oriented relative to one another, the preferably cylindrical or truncated cone-shaped orientation means, on the one hand, bears with its outer circumference against the interior of the elongated hole in the cathode plate / anode plate, and on the other hand, the preferably cylindrical or truncated cone-shaped orientation means, on the other hand, bears with its outer circumference against the interior of the tapered or stepped elongated hole (preferably of larger diameter) of the anode plate / cathode plate (see Figure 4 On the right). In this case, the elongated hole and the tapered or stepped elongated hole have essentially the same diameter in mutually relevant regions.

[0023] After the orientation step, the cathode plate and the anode plate can be fastened to each other, in particular welded to each other, in a fastening step of the assembly method. The cathode plate and / or the anode plate can be configured as an electrode plate according to the invention. In addition, the bipolar plate can be configured according to the invention after the fastening step of the assembly method.

[0024] In the method for stacking bipolar plates into a fuel cell stack (stack, stacking structure) according to the present invention, a plurality of bipolar plates having a diaphragm electrode unit between them are stacked one on top of the other into a fuel cell stack by means of a bipolar plate stacking device, wherein the stacking of the bipolar plates into the fuel cell stack is achieved by a bipolar plate positioning device in the bipolar plates, and the bipolar plate positioning device is at least partially constructed by a plate orienting device of the bipolar plates, by which the electrode plates are oriented relative to each other so as to be assembled into a bipolar plate.

[0025] The bipolar plate positioning device may include two plate stack through-slots. Here, a single plate stack through-slot may be formed by two through-slots of the plate orientation device of the electrode plate. Furthermore, a single through-slot of two mutually related through-slots of the electrode plate may be centered or positioned by a stacking device of a bipolar plate stacking device, wherein the bipolar plate is positioned in the fuel cell stack. For this purpose, the stacking device preferably has a cylindrical section for insertion through the relevant plate stack through-slot.

[0026] Furthermore, the corresponding plate stack through-slots can be formed by the oriented double holes and oriented double slits of the plate oriented device of the electrode plate of the bipolar plate. Furthermore, a single oriented hole of the oriented double hole can be effectively centered by the stacking device of the bipolar plate stacking device, wherein the oriented hole preferably has a circular profile with a protrusion (see Figure 5 In addition, a single orientation slot can be effectively centered or positioned by the stack of bipolar plate stacks, wherein the orientation slot is preferably configured as a tapered or stepped elongated hole (see Figure 5 On the right). The tapering or narrowing section of the elongated hole is preferably centered or positioned by means of a stack of components.

[0027] When stacking bipolar plates, bipolar plates with membrane electrode units arranged thereon can be stacked or bipolar plates and membrane electrode units can be stacked alternately. Positioning the bipolar plates when stacking the bipolar plates in a fuel cell stack can be performed by only a single electrode plate of the bipolar plates. Preferably, an electrode plate that is thicker than other electrode plates of the same bipolar plate is used. This is usually a cathode plate. The bipolar plate can be configured as a bipolar plate according to the invention. In addition, the bipolar plates can be assembled by the method according to the invention.

[0028] In particular, it should be noted that the features mentioned within the scope of the method, in particular the device features mentioned there (electrode plates (cathode plates, anode plates, bipolar plates) can be transferred to the claimed device. In addition, the features mentioned within the scope of the device, in particular the method features mentioned there (assembly method, stacking method) can be transferred to the claimed method. This also applies to the following description of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The invention is explained in detail below with reference to schematic and not to scale drawings based on embodiments. In the present invention, features can be configured as positive, i.e., present, or negative, i.e., absent. In this description, negative features are not explicitly described as features unless it is important according to the invention that the feature is absent. That is, the invention that is actually made and not constructed by the prior art consists in omitting the feature. The absence of a feature in an embodiment (negative feature) indicates that the feature is optional. In the merely exemplary figures of the drawings, it is shown:

[0030] Figure 1 : A simplified block diagram of an embodiment of a fuel cell unit of a fuel cell system for a fuel cell vehicle,

[0031] FIG. 2 : A top view of a bipolar plate constructed from a cathode plate and an anode plate according to the prior art for a fuel cell stack,

[0032] Figure 3 : a bipolar plate positioning device according to the invention, formed by plate orientation devices of the cathode plate and the anode plate of the bipolar plate, while eliminating other contours of the bipolar plate,

[0033] Figure 4 :Cathode plate (at Figure 3 and Figure 5 See also the underlined reference numerals in the figure) and the anode plate (see ... Figure 3 and Figure 5 (see also the reference numerals with dashed lines in the figure) when assembling the plate orientation device into a bipolar plate,

[0034] Figure 5 : the function of the bipolar plate positioning device at least partially constructed by the plate orientation devices of the cathode plate and the anode plate when stacking the bipolar plates into the fuel cell stack,

[0035] Figure 6 and Figure 7 :Method for assembling bipolar plates( Figure 6 ) and a method for stacking bipolar plates into a fuel cell stack ( Figure 7 ) is a simplified flowchart of the process. DETAILED DESCRIPTION

[0036] According to the electrode plate 101 / 102, that is, a "half" bipolar plate 100, that is, a cathode plate 101 or an anode plate 102 and a bipolar plate 100 (see Figures 3 to 5 ), and according to a method for assembling 1000 bipolar plates 100 (see Figure 6 ) and a method for stacking 2000 bipolar plates 100 into a fuel cell stack 10 for a low temperature polymer electrolyte fuel cell system for a fuel cell vehicle (i.e., a motor vehicle having a fuel cell or fuel cell system) (see Figure 7 ) describes the present invention in more detail.

[0037] Only the sections of the fuel cell system required for understanding the invention are shown in the drawings. Although the invention has been described and illustrated in detail by preferred embodiments, the invention is not limited to the disclosed embodiments. Other variations can be derived therefrom without departing from the scope of protection of the invention.

[0038] Figure 1 A fuel cell unit 1 according to a preferred embodiment is shown, which has at least one, in particular a plurality of, electrochemical individual fuel cells 11, 11, ... (single cells 11, 11, ...) of a bundle-integrated fuel cell stack 10, which are placed in a preferably fluid-tight stack housing 16. Each single cell 11 comprises an electrode chamber 12 configured as an anode chamber 12, which preferably has a gas diffusion layer (possibly containing a microporous particle layer), and an electrode chamber 13 configured as a cathode chamber 13, which preferably has a gas diffusion layer (possibly containing a microporous particle layer), which are spatially separated from each other and electrically separated from each other by a membrane of a membrane electrode unit 15. Here, the gas diffusion layer is preferably assigned to the membrane electrode unit 15.

[0039] A bipolar plate 100 is arranged respectively between two directly adjacent membrane electrode units 15, 15 containing associated anode chambers 12 and cathode chambers 13 (the separator plate assembly 100 is preferably composed of an anode plate 102 (electrode plate 102, monopolar plate 102) and a cathode plate 101 (electrode plate 101, monopolar plate 101), and the bipolar plate is used in particular to supply / discharge operating medium 3, 5 into the anode chamber 12 of the first single cell 11 and the cathode chamber 13 of the second single cell 11 directly adjacent thereto and also to realize an electrically conductive connection between these single cells 11, 11.

[0040] In order to supply the fuel cell stack 10 with its actual operating medium 3 (anode operating medium, actual fuel), 5 (cathode operating medium, usually air), the fuel cell unit 1 has an anode supply device 20 and a cathode supply device 30. The anode supply device 20 comprises in particular: a fuel reservoir 23 for the anode operating medium 3 (inflow); an anode supply path 21 with a shut-off / metering valve 27 and an injector 24; an anode exhaust gas path 22 for the anode exhaust gas medium 4 (usually outflowing into the surroundings 2); preferably a fuel recirculation line 25 (with a fluid conveying device 26 located therein) and, if necessary, a water separator.

[0041] The cathode supply device 30 includes, in particular: a cathode supply path 31 (preferably having a fluid conveying device 33) for a cathode operating medium 5 (usually flowing in from the surrounding environment 2); a cathode exhaust gas path 32 for a cathode exhaust gas medium 6 (usually flowing out into the surrounding environment 2), preferably having a turbine 34, if necessary a turbine of an exhaust gas turbocharger, in particular for the fluid conveying device 33, preferably having a humidity transmitter 36, if necessary an exhaust gas bypass valve 35 between the cathode supply path 31 and the cathode exhaust gas path 22; and, if necessary, a water separator.

[0042] In addition, the fuel cell unit 1 particularly includes a cooling medium supply device 40, through which the fuel cell can preferably be connected to the cooling circuit for temperature control by means of its bipolar plate 100 (cooling medium path 43) in a heat transfer manner. The cooling medium supply device 40 includes a cooling medium inflow path 41 and a cooling medium outflow path 42. The cooling medium 7 (inflow) and 8 (outflow) circulating in the cooling medium supply device 40 are preferably transported by means of at least one cooling medium conveying device 44. In addition to the fuel cell unit 1, the fuel cell system also includes peripheral system components, such as a controller, which can be a controller of the fuel cell vehicle itself.

[0043] 2 shows a bipolar plate 100 according to the prior art, wherein the bipolar plate 100 comprises two electrode plates 101, 102 welded to one another, namely a cathode plate 101 and an anode plate 102. In addition to its ports for the flow field of the medium and its paths 21, 22, 31, 32, 41, 42, the bipolar plate 100 also has a bipolar plate positioning device 107 (only prior art) and a plate orientation device 106 (only prior art) separate therefrom.

[0044] Here, the associated (double) through-cutting notches of the bipolar plate positioning device 107 and the plate orientation device 106 are arranged adjacent to one another in the bipolar plate 100 in corresponding longitudinal sections of the bipolar plate 100 (i.e., at the top right and bottom left in FIG. 2 ) by means of webs, i.e., the “body” of the bipolar plate 100 . That is, in order to orient the electrode plates 101 , 102 relative to the bipolar plate 100 and to stack the bipolar plates 100 in the fuel cell stack 10 , a relatively large space is required on the bipolar plate 100 , which space is not available for subsequent functions of the bipolar plate 100 . (dead area or dead space).

[0045] In the method for assembling such a bipolar plate according to the prior art, the cathode plate 101 and the anode plate 102 are oriented to each other by means of a plate orienting device (106) in the cathode plate 101 and a plate orienting device (106) in the anode plate 102. If the cathode plate 101 and the anode plate 102 are oriented by means of the plate orienting device 106, they are welded to each other.

[0046] In the subsequent method for stacking the bipolar plates 100 assembled in this way to form a fuel cell stack 100, the layers 100, 15 of the fuel cell stack 10, i.e. the alternating bipolar plates 100 and the membrane electrode units 15, are positioned in the bipolar plates 100 and the membrane electrode units 15 by means of the bipolar plate positioning device 107. A total of eight through-slots in the two electrode plates 101, 102 or four (double) through-slots in a single bipolar plate 100 are required for the assembly method and the stacking method.

[0047] Within the scope of the present invention, see below Figures 3 to 5 In the figure, if the reference numeral is assigned to the cathode plate 101 of the bipolar plate 100, it is underlined with a solid line; if the reference numeral is assigned to the anode plate 102 of the same bipolar plate 100, it is underlined with a dotted line. Of course, the reverse is also possible.

[0048] When stacking the fuel cell stack 10 by means of the bipolar plate positioning device, for example, the so-called hole-&slot-prinzip principle is used; similarly, see also Figure 3 . The bipolar plates 100 and the membrane electrode units 15 can thus be stacked very precisely on top of one another to form the fuel cell stack 10. Optimal tolerances can be achieved by only one side of the bipolar plate 100, which is always constructed from the cathode plate 101 and the anode plate 102, being responsible for the precise positioning of the bipolar plate 100. This is preferably the side of the bipolar plate 100 with the greater layer thickness. In the present case, this is preferably the cathode plate 101, which is currently constructed approximately 0.2 mm thicker than the anode plate 102.

[0049] Therefore, the cathode plate 101 has a diameter of, for example, 8.0 mm at its stacking hole 111 and the anode plate 102 has a diameter of, for example, 8.4 mm at its stacking hole 121. That is, the diameter of the stacking hole 111 of the cathode plate 101 is smaller than (and not less than or equal to) the diameter of the stacking hole 121 of the anode plate 102. If the stacking holes 111, 121 of the cathode plate 101 and the anode plate 102 have the same diameter, the common (double) through-slots 111, 121 in the bipolar plate 100 (see below, plate positioning stacking holes 131 (111, 121)) are about 7.8 mm due to positioning and tolerance, or approximately have an elliptical shape in a top view. The stacking pins 301 of the bipolar plate stacking device 300 must be selected to be smaller accordingly in order to stack the fuel cell stack 10 (see below).

[0050] If the stacking holes 111, 121 are arranged concentrically, and the stacking hole 111 of the cathode plate 101 has a diameter of 8.0 mm, and the stacking hole 121 of the anode plate 102 has a diameter of 8.4 mm, the stacking pin 301 can only be aligned with the cathode plate 101 and may have a diameter of almost about 8.0 mm (similarly see Figure 5 The diameter and, if necessary, the length of the stacking seams 112, 122 (see below, plate positioning stacking seams 132 (112, 122)) in the cathode plate 101 and the anode plate 102 can be handled in a similar manner (similarly see Figure 5 Right side). Thus, the fuel cell stack 10 can be built manually or automatically safely, with low tolerance and rationality. Of course, diameters other than the given dimensions may be used.

[0051] Of course, the cathode plate 101 and the anode plate 102 must be oriented relative to each other beforehand, i.e., when the cathode plate 101 and the anode plate 102 are assembled to form the bipolar plate 100. If the stacking holes 111, 121 are each designed as only circular stacking holes 111, 121 of different sizes and the stacking slots 112, 122 are each designed, for example, as only straight elongated holes 112, 122 of different sizes, they cannot be used to align the cathode plate 101 relative to the anode plate 102, because otherwise the cathode plate 101 cannot be correctly oriented relative to the anode plate 102.

[0052] According to the present invention, see Figures 3 to 6 , the plate orientation device 110 of the electrode plate 101, such as the cathode plate 101, and the plate orientation device 120 of the electrode plate 102, such as the anode plate 102, constitute a bipolar plate positioning device 105 (plate-connected: 110, 120 or plate-overlapped: 131, 132 (see below)) in the bipolar plate 100. That is, the plate orientation device 110 of the plate connection is constructed as the region 110 of the bipolar plate positioning device 105, and the plate orientation device 120 of the plate-overlapping is also constructed as the region 120 of the bipolar plate positioning device 105.

[0053] Here, the plate orientation devices 110, 120 (see Figure 5 ) In the method 1000 for assembling the bipolar plate 100, in the orientation step 1001 of the assembly method 1000, the electrode plates 101, 102 are oriented to each other. In the temporally subsequent step 1002, the fastening step 1002 of the method 1000, the electrode plates 101, 102 are fixed to each other. Thus, such a bipolar plate 100 can be stacked into a fuel cell stack 10 (method 2000, see below).

[0054] The bipolar plate positioning device 105 formed by the plate orientation devices 110, 120 (plate stacking through slots 131, 132, see below) is used to stack the bipolar plates 100 into the fuel cell stack 10 in a timely manner. This method for stacking bipolar plates 100 into a fuel cell stack 100 is described in detail in detail. Figure 7 Here, the bipolar plates 100 (step 2001) and the membrane electrode units 15 (step 2002) are alternately stacked, or the bipolar plates 100 with the membrane electrode units 15 arranged thereon are stacked (step 2010 replacing steps 2001 and 2002). If the fuel cell stack 10 has its expected number of layers, the stacking method 2000 ends in step 2020. The fuel cell stack 10 can then be placed in a stack housing 16, for example.

[0055] The plate orientation device 110 comprises two through slots 111, 112 in the electrode plate 101, and the plate orientation device 120 comprises two through slots 121, 122 in the electrode plate 102. The through slots 111, 121 / 112, 122 associated with one another are arranged here essentially concentrically in the bipolar plate 100. In the present case, the through slots 111, 121 associated with one another can be configured as orientation holes 111, 121 in the electrode plate 101, and the through slots 112, 122 associated with one another can be configured as orientation slits 112, 122 in the electrode plate 102. Of course, other shapes of the through slots 111, 121 / 112, 122 associated with one another can be used.

[0056] The mutually related through slots 111, 121 / 112, 122 of the plate orientation devices 110, 120 respectively form the plate stack through slots 131, 132 of the bipolar plate positioning device 105. In the present case, the plate stack through slot 131 is configured as a plate-overlapping plate positioning stack hole 131, which can also be referred to as a substantially concentric oriented double hole 111, 121. Furthermore, in the present case, the plate stack through slot 132 is configured as a plate-overlapping plate positioning stack seam 132, which can also be referred to as a substantially concentric oriented double seam 112, 122.

[0057] For the assembly method 1000 of the bipolar plate 100, the plate orientation device 200 is used to be joined to the plate orientation devices 110, 120 of the electrode plates 101, 102 ( Figure 4 ). Here, the plate orientation means 200 comprises a preferably shaped orientation means 201, in particular a mounting pin 201, for inserting through the through slots 111, 121. In addition, the plate orientation means 200 comprises a preferably cylindrical or truncated cone-shaped orientation means 202, in particular a mounting pin 201, for inserting through the through slots 112, 122.

[0058] For the stacking method 2000 of the fuel cell stack 10, the bipolar plate stacking device 300 is used to be joined to the bipolar plate positioning device 105 (110, 120) of the bipolar plate 100 ( Figure 5 ). Here, the bipolar plate stack device 300 includes a preferably cylindrical stack device 301, in particular a stacking pin 301, for inserting through the through slots 111, 121. In addition, the bipolar plate stack device 300 also includes a preferably cylindrical stack device 302, in particular a stacking pin 302, for inserting through the through slots 112, 122.

[0059] In the present case, the orientation hole 121 (through slot 121) has essentially only a circular contour 121, while the orientation hole 111 (through slot 111) has a circular contour with a protrusion 111. In this case (when the electrode plates 101, 102 are oriented and used for stacking the bipolar plates 100), the circular contour with the protrusion 111 is inscribed in the circular contour 121 ( Figures 3 to 5 left side).

[0060] Furthermore, in the present case, the oriented hole 122 (through slot 122) has essentially only a straight elongated hole profile 122, while the oriented hole 112 (through slot 112) has a tapered or stepped elongated hole profile 112. In this case (also when the electrode plates 101, 102 are oriented and used for stacking the bipolar plates 100), the tapered or stepped elongated hole profile 112 is inscribed in the straight elongated hole profile 122, in particular with its wider section ( Figures 3 to 5 on the right).

[0061] In the orientation step 1001, the molded assembly pin 201 acts on the projection with the circular contour of the projection 111 and accordingly only the circular contour 121 is centered, or vice versa, whereby the electrode plates 101, 102 are oriented at the longitudinal ends ( Figure 4 Left side). Furthermore, in the orientation step 1001, the cylindrical or truncated cone-shaped assembly pin 202 acts on the straight elongated hole contour 122 and accordingly orients the tapered or stepped elongated hole contour 112, or vice versa, whereby the electrode plates 101, 102 are oriented at the other longitudinal end ( Figure 4On the right side). In this case, the cylindrical or truncated-conical mounting pin 202 engages in the straight elongated hole contour 122 and in the wider section of the tapered or stepped elongated hole contour 112 .

[0062] When stacking 2001, 2010, only the circular contour with the protrusion 111 is centered on the columnar stacking component 301, or vice versa, whereby the bipolar plate 100 is positioned at one longitudinal end. Here, only the larger circular contour 121 is not centered directly on the columnar stacking component 301, but indirectly through the composite of the electrode plates 101, 102. In addition, when stacking 2001, 2010, the columnar stacking component 301 acts on the tapered or stepped elongated hole contour 112, or vice versa, whereby the bipolar plate 100 is positioned at the other longitudinal end ( Figure 5 Right side). The sectionally larger straight elongated hole contour 122 is not centered directly on the pillar stack component 302 but indirectly via the composite of the electrode plates 101 , 102 .

[0063] In summary, the mutually related through-slots 111, 121 / 112, 122 (respectively overlapping the plate orientation devices 110, 120) of the electrode plates 101, 102 (electrode plates 101, 102 that are not fixed to each other) can be constructed in particular in such a way that they can be centered / oriented with each other by the orientation device 201 (orientation holes 111, 121, if necessary, alternatively or additionally orientation slots 112, 122) and / or can be aligned with each other by the orientation device 202 with one or exactly one degree of freedom (orientation slots 112, 122, if necessary, alternatively or additionally orientation holes 111, 121) (see Figure 4 ).

[0064] In addition, the individual plate stack through-slots 131 (111, 121) / 132 (112, 122) of the bipolar plate 100 (electrode plates 101, 102 fixed to each other) can be designed in such a way that the bipolar plate 100 can be positioned during stacking by means of the stacking device 301 / 302 only by means of the individual through-slots 111 / 112 of the mutually related through-slots 111, 121 / 112, 122 of the plate stack through-slots 131 (111, 121) / 132 (112, 122) (see Figure 5 ). Preferably, the two through slots 131 (111, 121) / 132 (112, 122) are designed in such a way that only a single through slot 111, 112 is respectively assigned to the plate orientation device 110 of a single electrode plate 101 of the bipolar plate 100. Preferably, the thicker of the two electrode plates 101, (102) is usually the cathode plate 101.

[0065] If the through-slots 111 , 121 (orientation holes 111 , 121 , later plate stack through-slots 131 ) associated with each other have a circular shape as a whole (see Figures 3 to 5 Left side), they are centered together in the assembly method 1000 by the preferably formed orientation means 201 of the plate orientation means 200 (step 1001, see Figure 4 Left side). The formed orientation means 202 here essentially rests with its corners or corner regions on the inside against the two through-cutouts 111 , 121 (centering).

[0066] Furthermore, in the stacking method 2000, the preferably cylindrical stacking device 301 of the bipolar plate stacking device 300 is centered in the formed plate positioning through-slot 131 or vice versa (step 2001 or step 2010, see Figure 5 Left side). Of course, only one single through-slot 111 of the through-slots 111 , 121 associated with one another is centered as the plate positioning through-slot 131 , and this is the through-slot 111 which is inscribed in the through-slot 121 in a top view.

[0067] If the through-slots 112 , 122 (orientation slots 112 , 122 , later through-slots 132 of the sheet metal stack) associated with each other each have the shape of an elongated hole overall (see Figures 3 to 5 On the right side), they are centered or oriented together in the assembly method 1000 according to the preferred cylindrical or truncated cone-shaped orientation device 202 of the plate orientation device 200 (step 1001, see Figure 4 Here, the orientation means 202 is arranged in a first longitudinal end section of the elongated hole-like through-slot 112 , 122 (at the right side). Figure 4 In the figure, this is the left longitudinal end section). The orientation means 202 here essentially bears internally against the two through-cut notches 112 , 122 (centering / orientation).

[0068] Furthermore, in the stacking method 2000, the preferably cylindrical stacking device 302 of the bipolar plate stacking device 300 is centered or oriented in the formed plate positioning through-slot 132, or vice versa (step 2001 or step 2010, see Figure 5 On the right side). Of course, only one single through-slot 112 of the mutually related through-slots 111, 122 is centered or oriented as a plate positioning through-slot 132, and this is the through-slot 112 which is inscribed in the through-slot 122 in the top view. Here, the stacking device 302 is arranged in the second longitudinal end section of the elongated hole-shaped through-slot 112, 122 (at Figure 4 , this is the right longitudinal end section).

Claims

1. An electrode plate (101 / 102), i.e. a cathode plate (101) or an anode plate (102), for a bipolar plate (100) of a fuel cell stack (10), in particular for a fuel cell vehicle, the electrode plate comprising: a plate orientation device (110 / 120) for orienting the electrode plate (101 / 102) relative to a second electrode plate (102 / 101) corresponding to the electrode plate and having its plate orientation device (120 / 110), and for assembling the two electrode plates (102, 101) into a bipolar plate (100), It is characterized in that The plate orientation device (110 / 120) at least partially forms a region (110 / 120) of a bipolar plate positioning device (105; 110, 120) of the bipolar plate (100) for stacking the bipolar plate (100) into the fuel cell stack (10).

2. The electrode plate (101 / 102) according to the preceding claim, characterized in that The contour of the plate orientation device (110 / 120) is arranged in the electrode plate (101 / 102) so that it can substantially coincide with the contour of the plate orientation device (120 / 110) of the second electrode plate (102 / 101) of the same bipolar plate only in points or sections.

3. The electrode plate (101 / 102) according to any one of the preceding claims, characterized in that The electrode plate (101 / 102) does not include bipolar plate positioning means for the bipolar plate (100) which are functionally substantially or completely independent of the plate orientation means (105) thereof and which are at least partially independent of the plate orientation means (105), the plate orientation device (110 / 120) is arranged inside the electrode plate (101 / 102), substantially completely inside the electrode plate or only inside the electrode plate, The plate orientation device (110 / 120) comprises at least one notch (111 / 121, 112 / 122), in particular at least one through-notch (111 / 121, 112 / 122), in the electrode plate (101 / 102), and / or The plate orientation device (110 / 120) comprises orientation holes (111 / 121) on the one hand and orientation slots (112 / 122) on the other hand in the electrode plate (101 / 102).

4. A bipolar plate (100) for a fuel cell stack (10) of a fuel cell, the fuel cell being particularly used in a fuel cell vehicle, the bipolar plate comprising a cathode plate (101) and an anode plate (102) fixedly connected to the cathode plate, It is characterized in that The plate orientation device (110) of the cathode plate (101) and the plate orientation device (120) of the anode plate (102) together at least partially form a bipolar plate positioning device (105) for stacking the bipolar plates (100) into a fuel cell stack (10), and the cathode plate (101) and the anode plate (102) are oriented relative to each other in the bipolar plate (100) by means of the plate orientation device of the cathode plate and the plate orientation device of the anode plate.

5. The bipolar plate (100) according to the preceding claim, characterized in that the combination of the plate orientation means (110, 120) of the cathode plate (101) and the anode plate (102) at least partially forms a bipolar plate positioning means (105) of the bipolar plate (100), Neither the cathode plate (101) nor the anode plate (102) has a plate orientation device (106) solely for orienting the cathode plate (101) and the anode plate (102) relative to each other to form the bipolar plate (100), and / or The bipolar plate (100) has no plate orientation means (106) separate from the bipolar plate positioning means (107) of the bipolar plate, neither in the cathode plate (101) nor in the anode plate (102) of the bipolar plate.

6. The bipolar plate (100) according to any one of the preceding claims, characterized in that The cathode plate (101) and the anode plate (102) are stacked and fixedly constructed to form a bipolar plate (100), such that: The contours of the plate orientation devices (110, 120) relative to one another are arranged such that the contour of the first plate orientation device (110 / 120) substantially coincides with the contour of the second plate orientation device (120 / 120) only in points or in sections, In a top view of the bipolar plate (100), the contour of the first plate orientation device (110 / 120) is inscribed in or surrounds the contour of the second plate orientation device (120 / 110), and / or In a top view of the bipolar plate (100), the surface of the first plate orientation device (110 / 120) is arranged in the bipolar plate (100) such that it coincides only partially with the surface of the second plate orientation device (120 / 110).

7. The bipolar plate (100) according to any one of the preceding claims, characterized in that The plate orientation devices (110, 120) of the cathode plate (101) and the anode plate (102) form two plate stacking through-notches (131, 132) in the bipolar plate (100) for stacking the bipolar plate (100) into the fuel cell stack (10), The plate orientation device (110) of the cathode plate (101) and the plate orientation device (120) of the anode plate (102) respectively comprise two through slots (111, 112; 121, 122), wherein the four through slots (111, 112; 121, 122) form two through slots (111 / 121, 112 / 122) in the bipolar plate (100) as bipolar plate positioning devices (105), and / or The two through-notches (111, 112; 121, 122) not only in the cathode plate (101) but also in the anode plate (102) are respectively constructed as directional holes (111, 121) and directional slits (112, 122), and the directional holes and the directional slits (111, 121; 112, 122) form directional double holes (111, 121) and directional double slits (112, 122) in the bipolar plate (100) as bipolar plate positioning devices (105).

8. The bipolar plate (100) according to any one of the preceding claims, characterized in that The orientation hole (121) of one plate orientation device (120) has only a circular contour (121), while the orientation hole (111) of the other plate orientation device (110) has a circular contour with a protrusion (111), The orientation slot (122) of one plate orientation device (120) is configured as an elongated hole (122), while the orientation slot (112) of the other plate orientation device (110) is configured as a tapered or stepped elongated hole (112), and / or The orientation hole (111) having a circular contour with a protrusion (111) is inscribed in the orientation hole (121) having only a circular contour (121), and the orientation slot (112) as a tapered or stepped elongated hole (112) is at least partially inscribed in the orientation slot (122) as an elongated hole (122).

9. A method (1000) for assembling a bipolar plate (100) of a fuel cell stack (10) for a fuel cell, in particular for a fuel cell vehicle, wherein: In an orienting step (1001) of the method (1000), the cathode plate (101) and the anode plate (102) of the formed bipolar plate (100) are oriented relative to each other and fixed relative to each other in a chronologically subsequent fastening step (1002) of the method (1000), It is characterized in that In the orienting step (1001), the cathode plate (101) and the anode plate (102) are oriented relative to each other by plate orienting devices (110, 120) of the cathode plate (101) and the anode plate (102), and the plate orienting devices (110, 120) at least partially form bipolar plate positioning devices (105) in the formed (1002) bipolar plates (100) for stacking the bipolar plates (100) into a fuel cell stack (10).

10. Assembly method (1000) according to the preceding claim, characterized in that The plate orientation devices (110, 120) of the cathode plate (101) and the anode plate (102) respectively include two through slots (111, 112; 121, 122), wherein in the orientation step (1001): the mutually associated through slots (111, 121; 112, 122) of the cathode plate (101) and the anode plate (102) are arranged at least in sections substantially concentrically with one another, aligning the two mutually related through slots (111, 121) of the cathode plate (101) and the anode plate (102) with each other in the middle plane by means of the shaped orientation means (201) of the plate orientation means (200), The two mutually related through-cutting notches (111, 121) of the shaped orientation means (201) are configured as an orientation hole (121) having only a circular contour (121) and as an orientation hole (111) having a circular contour with a projection (111), orienting two mutually related through slots (112, 122) of the cathode plate (101) and the anode plate (102) with one degree of freedom or exactly one degree of freedom in a / the middle plane by means of an orientation device (202) of a / the plate orientation device (200), and / or The two mutually interrelated through slots (112, 122) for the orientation means (202) are designed as an orientation slot (122) as an elongated hole (122) and as an orientation slot (112) as a tapered or stepped elongated hole (112).

11. The assembly method (1000) according to any one of the preceding claims, characterized in that: After the orientation step (1001), in a fastening step (1002) of the assembly method (1000), the cathode plate (101) and the anode plate (102) are fixed to each other, in particular welded to each other, The cathode plate (101) and / or the anode plate (102) are configured as electrode plates (101, 102) according to any one of the preceding claims, and / or The bipolar plate (100) according to any one of the preceding claims is constructed temporally after the fastening step (1002) of the assembly method (1000).

12. A method for stacking (2000) bipolar plates (100) into a fuel cell stack (10) for a fuel cell, in particular for a fuel cell vehicle, wherein: A plurality of bipolar plates (100) having membrane electrode units (15) located therebetween are stacked one on top of the other (2001, 2002; 2010) to form a fuel cell stack (10) by means of a bipolar plate stacking device (300), characterized in that: The bipolar plates (100) are stacked (2001, 2010) into the fuel cell stack (10) by means of a bipolar plate positioning device (105) in the bipolar plates (100), wherein: The bipolar plate positioning device (105) is at least partially constructed by plate orientation devices (110, 120) of the electrode plates (101, 102) of the bipolar plate (100), and the electrode plates (101, 102) are oriented (1000) to each other by the plate orientation devices to assemble them into the bipolar plate (100).

13. The stacking method (2000) according to the preceding claim, characterized in that The bipolar plate positioning device (105) comprises two plate stacking through slots (131, 132), wherein: a single plate stack through-slot (131 / 132) is formed by a double through-slot (111, 121 / 112, 122) of the plate orientation means (110, 120) of the electrode plates (101, 102), a single through-slot (111 / 121, 112 / 122) of two mutually related through-slots (111, 121; 112, 122) of the electrode plates (101, 102) being centered or positioned by a stacking device (301, 302) of the bipolar plate stacking device (300), wherein the bipolar plate (100) is positioned in the fuel cell stack (10), The corresponding plate stack through-slots (131, 132) are formed by the directional double holes (111, 121) and directional double seams (112, 122) of the plate directional devices (110, 120) of the electrode plates (101, 102) of the bipolar plate (100), The single directional hole (111) of the directional double hole (111, 121) is effectively centered by the stacking device (301) of the bipolar plate stacking device (300), wherein the directional hole (111) preferably has a circular profile with a protrusion (111), and / or A single orientation slot (112) is effectively centered or positioned through the stack (302) of the bipolar plate stack (300), wherein the orientation slot (112) is preferably configured as a tapered or stepped elongated hole (112).

14. The stacking method (2000) according to any one of the preceding claims, characterized in that: When stacking (2001, 2002; 2010) the bipolar plates (100), the bipolar plates (100) having the membrane electrode units (15) arranged thereon are stacked (2010) or the bipolar plates (100) and the membrane electrode units (15) are alternately stacked (2001, 2002), When stacking (2001, 2010) bipolar plates (100), positioning the bipolar plates (100) into the fuel cell stack (10) is performed by only a single electrode plate (101 / 102) of the bipolar plates (100), and / or The bipolar plate (100) is constructed according to the bipolar plate of any one of the preceding claims and / or is assembled by the method of any one of the preceding claims.

15. A fuel cell, a fuel cell unit (1) or a fuel cell system, in particular for a fuel cell vehicle, characterized in that: An electrode plate (101 / 102) of a fuel cell, a fuel cell unit (1) or a fuel cell system, wherein the electrode plate is constructed according to any one of the preceding claims, A bipolar plate (100) for a fuel cell, a fuel cell unit (1) or a fuel cell system according to any one of the preceding claims, A bipolar plate (100) for a fuel cell, a fuel cell assembly (1) or a fuel cell system assembled by a method (1000) according to any one of the preceding claims, and / or A fuel cell, a fuel cell assembly (1) or a fuel cell stack (10) of a fuel cell system is stacked by the method (2000) according to any of the preceding claims.

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