Bipolar plate and electrochemical cell stack

Abstract

The invention provides a bipolar plate which comprises an anode plate and a cathode plate, the anode plate and the cathode plate are stacked together, each of the anode plate and the cathode plate comprises a cooling liquid port, a cooling liquid channel, a cooling liquid distribution area and a cooling liquid distribution channel, and the cooling liquid distribution area of the anode plate is communicated with the cooling liquid distribution channel of the cathode plate at the same end; the cooling liquid distribution area of the cathode plate is communicated with the cooling liquid distribution channel of the anode plate at the same end; and a first blocking part is arranged in the at least one cooling liquid distribution area and extends along the extension direction of the cooling liquid distribution channel communicated with the at least one cooling liquid distribution area, so that a part of cooling liquid flowing in the at least one cooling liquid distribution area is changed to flow along the extension direction by the first blocking part. The invention also provides an electrochemical cell stack comprising the bipolar plate. According to the application, the distribution of the cooling liquid can be more uniform.

Description

Technical Field

[0001] The present application relates to the technical field of electrochemical cells, and in particular to a bipolar plate and an electrochemical cell stack including the bipolar plate. Background Art

[0002] With the development of new energy technologies, the use of electrochemical cell stacks as power sources is gaining increasing attention from researchers and the market. For example, as an important type of electrochemical cell stack, fuel cell stacks have been widely used in electric vehicles, portable power sources, and other fields. A fuel cell stack generally includes a plurality of fuel cell units stacked together, and each fuel cell unit, except for the fuel cell units at the ends, includes two bipolar plates shared with adjacent fuel cell units and a membrane electrode assembly sandwiched between the two bipolar plates.

[0003] like Figures 1 to 3 As shown, the existing bipolar plate is usually welded by stacking an anode plate 10 and a cathode plate 20, and an air inlet 11, a coolant inlet 13 and a hydrogen inlet 15 are provided at one end of either the anode plate 10 or the cathode plate 20, and a hydrogen outlet 16, a coolant outlet 14 and an air outlet 12 are provided at the other end, wherein the air inlet 11 and the hydrogen inlet 15 are respectively arranged on both sides of the coolant inlet 13, and the hydrogen outlet 16 and the air outlet 12 are also respectively arranged on both sides of the coolant outlet 14.

[0004] like Figure 1 As shown, a channel extending from one end to the other end is formed between the two ends of the anode plate 10, wherein the outer surface (i.e. Figure 1 The channel (the back side of the surface seen in FIG. 1 ) is used to allow hydrogen from the hydrogen inlet 15 to flow through it and reach the hydrogen outlet 16, and can therefore be referred to as a hydrogen channel 31 (eg, Figure 3 In addition, a hydrogen inlet distribution area is provided between the hydrogen inlet 15 and the hydrogen channel of the anode plate 10, which is generally embodied as an inclined channel from the hydrogen inlet 15 to the hydrogen channel. Figure 2 As shown, a channel extending from one end to the other end is formed (e.g., stamped) between the two ends of the cathode plate 20, wherein the outer surface (i.e., Figure 2 The channel (the back side of the surface seen in FIG. 1 ) is used to allow air from the air inlet 11 to flow through it and reach the air outlet 12, and can therefore be referred to as an air channel 32 (eg, Figure 3 Similarly, an air inlet distribution area is also provided between the air inlet 11 of the cathode plate 20 and the air channel, which is generally embodied as an inclined channel from the air inlet 11 to the air channel. When the anode plate 10 and the cathode plate 20 are stacked together, the inner surface ( Figure 1 The surface seen in FIG. 20 ) and the inner surface of the cathode plate 20 ( Figure 2 The cooling liquid channel 17 is formed by a channel on the surface of the anode plate 10 (see FIG. 1 ). In order to allow the cooling liquid to enter the cooling liquid channel 17 from the cooling liquid inlet 13, a cooling liquid distribution area 18 is provided on the inner surface of the anode plate 10 and the inner surface of the cathode plate 20, respectively. The cooling liquid from the cooling liquid inlet 13 first enters the cooling liquid distribution area 18, and then is divided into two paths, one path enters the inclined cooling liquid distribution channel 19 formed at a position corresponding to the hydrogen inlet distribution area on the inner surface of the anode plate 10, and the other path enters the inclined cooling liquid distribution channel 19 formed at a position corresponding to the air inlet distribution area on the inner surface of the cathode plate 20, and then enters the cooling liquid channel 17, as shown in FIG. Figure 4 It should be noted that Figure 4 In order to facilitate the display of the structure of the cooling liquid channel 17, the anode plate 10 is shown in a transparent manner, wherein the dotted arrows roughly represent a cooling liquid flowing on one side of the anode plate 10, and the solid arrows roughly represent another cooling liquid flowing on the cathode plate 20 side.

[0005] However, in the above-mentioned conventional bipolar plates, the coolant flow distribution in each coolant channel is uneven, especially on both sides of the bipolar plate (i.e. Figure 4 The coolant flow rate in the channels on the upper and lower sides (as shown in FIG) is greater than that in the middle channel. Figure 5 As shown in the test results. Therefore, due to the uneven distribution of the coolant flow, the temperature distribution of the fuel cell stack is also uneven, which affects the working stability and durability of the fuel cell stack.

[0006] In addition to the fuel cell stack illustrated above, similar problems also exist in electrochemical cells that use other gas media (for example, ammonia, coal gas, natural gas, biomass gas, etc.) or solid electrolytes as reactants, as long as similar coolant distribution areas, coolant distribution channels and coolant channels are used.

[0007] Therefore, there is a need to modify the bipolar plates of existing electrochemical cell stacks. Summary of the invention

[0008] The purpose of the present application is to provide an improved bipolar plate and an electrochemical cell stack including the bipolar plate, so as to achieve uniform distribution of the coolant.

[0009] To this end, according to one aspect of the present application, a bipolar plate is provided, which is used in an electrochemical battery stack, the bipolar plate comprising: an anode plate and a cathode plate stacked on each other, each of the anode plate and the cathode plate having a first end, a second end opposite to the first end, and a body portion located between the first end and the second end, wherein each of the anode plate and the cathode plate comprises: a cooling liquid port, which is arranged at the first end and the second end; a cooling liquid channel, which is arranged on the inner surface of the body portion; a cooling liquid distribution area, which is arranged on the inner surface of the body portion and communicated with the cooling liquid port; and a cooling liquid distribution channel, which is arranged on the inner surface of the body portion and communicated with the cooling liquid port. The cooling liquid channels are connected, wherein the cooling liquid distribution channel is inclined relative to the flow direction of the cooling liquid discharged from or entering the cooling liquid port; wherein the cooling liquid distribution area of ​​the anode plate is connected to the cooling liquid distribution channel of the cathode plate located at the same end, and the cooling liquid distribution area of ​​the cathode plate is connected to the cooling liquid distribution channel of the anode plate located at the same end; and wherein a first blocking portion is provided in at least one cooling liquid distribution area, and the first blocking portion extends along the extension direction of the cooling liquid distribution channel connected to the at least one cooling liquid distribution area, so that a portion of the cooling liquid flowing in the at least one cooling liquid distribution area is changed by the first blocking portion to flow along the extension direction.

[0010] According to one embodiment of the present application, the first blocking portion extends from a first side of the at least one coolant distribution area toward a second side of the at least one coolant distribution area opposite to the first side, and the first blocking portion is spaced apart from the second side, and the first side is closer to the coolant port than the second side.

[0011] According to an embodiment of the present application, the first blocking portion is disposed at a position of the at least one coolant distribution area corresponding to a middle position of the connected coolant distribution channel.

[0012] According to one embodiment of the present application, a second blocking portion separated from the first blocking portion is provided in the at least one coolant distribution area and upstream of the first blocking portion, the second blocking portion extends from the second side of the at least one coolant distribution area toward the first side, and the second blocking portion is spaced apart from the first side.

[0013] According to an embodiment of the present application, the second blocking portion is disposed at a position of the at least one coolant distribution area corresponding to an edge position of the connected coolant distribution channel close to the coolant port.

[0014] According to an embodiment of the present application, the first blocking portion and the second blocking portion are arranged to be parallel to each other.

[0015] According to one embodiment of the present application, the distance between the first blocking portion and the second side of the at least one coolant distribution area and the distance between the second blocking portion and the first side of the at least one coolant distribution area are respectively one half to one third of the extension length of the first blocking portion and the second blocking portion.

[0016] According to one embodiment of the present application, within the at least one cooling liquid distribution area, the anode plate and the cathode plate are arranged to gradually tilt from a first side of the at least one cooling liquid distribution area toward a second side of the at least one cooling liquid distribution area, so that the height of the at least one cooling liquid distribution area gradually decreases from the first side toward the second side, and the first side is closer to the cooling liquid port than the second side.

[0017] According to one embodiment of the present application, a first reaction gas channel corresponding to the coolant channel and a first reaction gas distribution channel corresponding to the coolant distribution channel are provided on the outer surface of the anode plate, a second reaction gas channel corresponding to the coolant channel and a second reaction gas distribution channel corresponding to the coolant distribution channel are provided on the outer surface of the cathode plate, and a first gas port and a second gas port are respectively provided on both sides of the coolant port, the first gas port is connected to the first reaction gas channel and the first reaction gas distribution channel, and the second gas port is connected to the second reaction gas channel and the second reaction gas distribution channel.

[0018] According to another aspect of the present application, an electrochemical cell stack is provided, comprising: a first bipolar plate and a second bipolar plate, wherein the anode plate of the first bipolar plate and the cathode plate of the second bipolar plate face each other; and a membrane electrode assembly, wherein the membrane electrode assembly is arranged between the first bipolar plate and the second bipolar plate; wherein each of the first bipolar plate and the second bipolar plate is a bipolar plate as described above.

[0019] By setting a blocking portion in the coolant distribution area of ​​the bipolar plate, the flow direction of the coolant can be rotated to the same direction as the coolant distribution channel before entering the inclined coolant distribution channel, thereby allowing more coolant to flow into the middle coolant channel of the bipolar plate, while reducing the coolant flowing into the coolant channels on both sides, thereby making the flow of the coolant more uniform. In addition, the pressure drop caused by the blocking portion set in this way is small, and will not cause a significant increase in the power consumption of the coolant supply pump.

[0020] In addition, in the coolant distribution area, the anode plate and the cathode plate can be arranged to be inclined from the coolant port toward the coolant distribution channel, so that when the coolant flows in the coolant distribution area, a portion of the coolant can continue to flow to the middle coolant distribution channel at a speed, instead of all the coolant having to turn two 90 degrees to reach the inclined coolant distribution channel. Therefore, in the bipolar plate and electrochemical cell of the present application, the pressure drop of the coolant flowing into the middle coolant distribution channel can be further reduced, and the uniformity of the coolant is much better than the design of the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The exemplary embodiments of the present application will be described in detail below with reference to the accompanying drawings. It should be understood that the embodiments described below are only used to explain the present application, rather than to limit the scope of the present application. In the accompanying drawings:

[0022] Figure 1 is a schematic plan view of an anode plate of a bipolar plate in the prior art;

[0023] Figure 2 is a schematic plan view of a cathode plate of a bipolar plate in the prior art;

[0024] Figure 3 Is Figure 1 The anode plate and Figure 2 A schematic partial cross-sectional view of a bipolar plate assembled from a cathode plate is shown;

[0025] Figure 4 Is Figure 1 The anode plate and Figure 2 A schematic plan view of a bipolar plate assembled from a cathode plate is shown, showing a coolant flow field;

[0026] Figure 5 yes Figure 4 Schematic diagram of flow distribution of coolant flow field shown;

[0027] Figure 6 yes Figure 4 A schematic partial enlarged view of the bipolar plate shown;

[0028] Figure 7 is along Figure 6 A schematic partial cross-sectional view taken along line II' in FIG.

[0029] Figure 8 is a schematic plan view of an anode plate according to an exemplary embodiment of the present application;

[0030] Fig. 9 is a schematic plan view of a cathode plate according to an exemplary embodiment of the present application;

[0031] Fig.10Is Figure 8 The anode plate and Fig. 9 A schematic plan view of a bipolar plate assembled from a cathode plate is shown, showing a coolant flow field;

[0032] Fig.11 yes Fig.10 A schematic partial enlarged view of the bipolar plate shown;

[0033] Fig.12 is along Fig.11 A schematic partial cross-sectional view taken along line II-II' in FIG.

[0034] Fig.13 yes Fig.10 Schematic diagram of flow distribution of coolant flow field shown. DETAILED DESCRIPTION

[0035] The preferred embodiments of the present application are described in detail below with reference to examples. In the embodiments of the present application, the present application is described by taking a bipolar plate for a fuel cell stack as an example. However, it should be understood by those skilled in the art that these exemplary embodiments do not mean any limitation to the present application. In addition, the features in the embodiments of the present application may be combined with each other unless there is a conflict. In different drawings, the same components are represented by the same reference numerals, and other components are omitted for the sake of brevity, but this does not mean that the bipolar plates and electrochemical cell stacks of the present application may not include other components. It should be understood that the size, proportional relationship and number of components of the components in the drawings are not intended to limit the present application.

[0036] In view of the problem of uneven coolant distribution in the prior art, the applicant conducted research and found that the reason for the above phenomenon is that when the coolant flows in the coolant channel, the pressure drop in the middle channel is higher than the pressure drop in the channels on both sides. Further research found that the coolant entering the middle channel needs to turn two 90-degree angles, while the coolant entering the channels on both sides does not need to turn such a large angle. Figure 6 and Figure 7 As shown, the coolant from the coolant inlet 13 flows along the coolant distribution area 18 located on the inner surface of the cathode plate 20 to the coolant distribution channel 19 on the inner surface of the anode plate 10. Here, the coolant needs to turn 90 to enter the coolant distribution channel 19 of the anode plate 10 (as shown in FIG. Figure 7 ), and then turn 90 degrees to flow along the coolant distribution channel 19 (as shown by the upward arrow in FIG. Figure 7 In the figure, the cooling liquid is directed to the upper right of the main body, and then the cooling liquid is directed to the main body. Figure 6 and Figure 7Although not specifically shown in the figure, the coolant from the coolant inlet 13 also flows along the coolant distribution area 18 on the inner surface of the anode plate 10 to the coolant distribution channel 19 on the inner surface of the cathode plate 20. Here, the coolant also needs to turn 90 degrees to enter the coolant distribution channel 19 of the cathode plate 20, and then turn 90 degrees again to flow along the coolant distribution channel 19 before entering the coolant channel 17 located in the body part. Therefore, this two 90-degree rotations make the pressure drop of the coolant entering the middle channel larger. In contrast, the coolant does not need to turn such a large angle to enter the coolant channels on both sides from the coolant distribution area 18 of the anode plate 10 and the coolant distribution area 18 of the cathode plate 20. For example, it can directly enter the channels on both sides, so that the pressure drop of the coolant in the channels on both sides is smaller. Therefore, the pressure drop of the coolant in the channels on both sides and the middle channel is different, resulting in uneven distribution of the coolant.

[0037] In view of the above analysis, the present application proposes an improved bipolar plate and an electrochemical battery stack including the bipolar plate. Figures 8 to 12 It should be noted that the bipolar plate of the present application is improved on the basis of the existing bipolar plate. Therefore, except for the cooling liquid distribution area, the bipolar plate of the present application can be used in the same manner as the reference Figures 1 to 3 The bipolar plates described herein are understood to have the same or similar structures, and thus repeated descriptions will be omitted.

[0038] Specifically, the present application proposes a bipolar plate 100 (such as Fig.10 As shown in FIG. 1 , which is used in an electrochemical battery cell, the bipolar plate may include an anode plate 50 and a cathode plate 60 stacked on each other. The anode plate 50 and the cathode plate 60 may be stamped metal plates, composite plates, etc., and are connected together by, for example, welding to form the bipolar plate 100. The anode plate 50 and the cathode plate 60 each have a first end (such as Figures 8 to 10 The left end shown), the second end opposite to the first end (as shown Figures 8 to 10 The first end and the second end of the bipolar plate 100 correspond to the first end and the second end of the anode plate 50 and the cathode plate 60, respectively.

[0039] like Figure 8 and Fig. 9As shown, similar to the existing bipolar plate structure, the first end of each of the anode plate 50 and the cathode plate 60 is provided with an air inlet 51, a coolant inlet 53 and a hydrogen inlet 55, and the second end is provided with a hydrogen outlet 56, a coolant outlet 54 and an air outlet 52, wherein the air inlet 51 and the hydrogen inlet 55 are respectively arranged on both sides of the coolant inlet 53, and the hydrogen outlet 56 and the air outlet 52 are also respectively arranged on both sides of the coolant outlet 54. However, the present application is not limited to the arrangement of the above-mentioned ports, and the positions and arrangements of the above-mentioned inlets and outlets can be arbitrarily exchanged as needed. Therefore, considering the exchange between the inlet and the outlet, the air inlet 51 and the air outlet 52 can be collectively referred to as the first gas port, the coolant inlet 53 and the coolant outlet 54 can be collectively referred to as the coolant port, and the hydrogen inlet 55 and the hydrogen outlet 56 can be collectively referred to as the second gas port. For the convenience of description, the above configuration is described as an example in this article, and the structure of the first end is mainly described in detail, while the second end can adopt the same structure as the first end, so the repeated description will be omitted.

[0040] It should be noted that, in this document, the inner surfaces of the anode plate 50 and the cathode plate 60 refer to the surfaces facing each other when the two are stacked together to form a bipolar plate, while the outer surfaces are the opposite surfaces of the two. Figure 8 and Fig. 9 The inner surfaces of the anode plate 50 and the cathode plate 60 are shown respectively, and the outer surfaces thereof have matching channel structures accordingly. Specifically, the inner surface of the body portion located between the first end and the second end of the anode plate 50 is formed with a cooling liquid channel 57 extending at both ends, and the outer surface (i.e. Figure 8 A hydrogen channel corresponding to the coolant channel 57 is provided on the back side of the surface seen in FIG. Figure 3 At the first end of the anode plate 50, as shown Figure 8 As shown in FIG. 1 , a hydrogen distribution channel forming a hydrogen inlet distribution area is provided between the hydrogen inlet 55 and the hydrogen channel on the outer surface of the anode plate 50, and a coolant distribution channel 59 corresponding to the hydrogen distribution channel is formed on the inner surface of the anode plate 50 at a position corresponding to the hydrogen inlet distribution area. Fig. 9 As shown, at the first end of the cathode plate 60, a cooling liquid channel 57 extending at both ends is formed on the inner surface of the body portion located between the first end and the second end of the cathode plate 60, and a cooling liquid channel 57 extending at both ends is formed on the outer surface (i.e. Fig. 9 The back side of the surface seen in FIG. 1 is provided with air channels corresponding to the coolant channels 57, similar to Figure 3In addition, an air distribution channel forming an air inlet distribution area is provided between the air inlet 51 and the air channel on the outer surface of the cathode plate 60, and a coolant distribution channel 59 corresponding to the air distribution channel is formed on the inner surface of the cathode plate 60 at a position corresponding to the air inlet distribution area.

[0041] When the anode plate 50 and the cathode plate 60 are stacked together, the inner surface ( Figure 8 The cooling liquid channel 57 on the surface (seen in FIG. 1 ) and the inner surface (seen in FIG. 1 ) of the cathode plate 60 Fig. 9 The cooling liquid channel 57 on the surface (seen in FIG. 1 ) forms an overall cooling liquid channel, similar to Figure 3 As shown. Due to the connection between the hydrogen inlet 55, the hydrogen distribution channel and the hydrogen channel on the outer surface of the anode plate 50, the coolant distribution channel 59 on the inner surface of the anode plate 50 is inclined relative to the flow direction of the coolant discharged from the coolant inlet 53, and cannot be directly connected to the coolant inlet 53. Similarly, due to the connection between the air inlet 51, the air distribution channel and the air channel on the outer surface of the cathode plate 60, the coolant distribution channel 59 on the inner surface of the cathode plate 60 is inclined relative to the flow direction of the coolant discharged from the coolant inlet 53, and cannot be directly connected to the coolant inlet 53. Therefore, at the first end of the bipolar plate, a coolant distribution area 58 connected to the coolant inlet 53 is provided on the inner surface of the anode plate 50 and the inner surface of the cathode plate 60, respectively. The coolant distribution area 58 is a concave cavity formed on the inner surface of the anode plate 50 and the cathode plate 60, which is arranged side by side with the coolant distribution channel 59 arranged on the same plate. By setting the cooling liquid distribution area 58, the cooling liquid distribution area 58 on the anode plate 50 at the same end can be connected with the cooling liquid distribution channel 59 on the cathode plate 60, and the cooling liquid distribution area 58 on the cathode plate 60 is connected with the cooling liquid distribution channel 59 on the anode plate 50, so that the cooling liquid can flow into the cooling liquid channel 57.

[0042] For example, the coolant from the coolant inlet 53 first enters the coolant distribution area 58, and then is divided into two paths, one path enters the coolant distribution area 59 on the inner surface of the anode plate 50, and then enters the coolant distribution channel 59 on the inner surface of the cathode plate 60, and the other path enters the coolant distribution area 58 on the inner surface of the cathode plate 60, and then enters the coolant distribution channel 59 on the inner surface of the anode plate 50, and finally the two paths enter the coolant channel 57.

[0043] In the bipolar plate according to the present application, a first blocking portion 71 is provided in the cooling liquid distribution area 58 of the anode plate 50, and the first blocking portion 71 extends along the extension direction of the cooling liquid distribution channel 59 of the cathode plate 60 located at the same end, as shown in FIG. Figure 8The first blocking portion 71 can change a portion of the coolant flowing in the coolant distribution area 58 of the anode plate 50 to flow along the extension direction of the coolant distribution channel 59 of the cathode plate 60 by the first blocking portion, as shown in FIG. Fig.10 and Fig.11 Similarly, a first blocking portion 71 is provided in the cooling liquid distribution area 58 of the cathode plate 60, and the first blocking portion 71 extends along the extension direction of the cooling liquid distribution channel 59 of the anode plate 60 located at the same end, as shown in FIG. Fig. 9 The first blocking portion 71 can change a portion of the coolant flowing in the coolant distribution area 58 of the cathode plate 60 to flow along the extension direction of the coolant distribution channel 59 of the anode plate 50 by the first blocking portion, as shown in FIG. Fig.10 and Fig.11 It should be noted that Fig.10 and Fig.11 In order to facilitate the display of the cooling liquid flow field, the anode plate 50 is shown in a transparent manner, wherein the dotted arrows roughly represent a cooling liquid flowing on one side of the anode plate 50, and the solid arrows roughly represent another cooling liquid flowing on the cathode plate 60 side.

[0044] In this way, by setting the first blocking portion, the flow direction of the coolant can be rotated to the same direction as the coolant distribution channel before entering the inclined coolant distribution channel. Therefore, more coolant is allowed to flow into the middle coolant channel, while the coolant flowing into the coolant channels on both sides is reduced, thereby making the flow of the coolant more uniform. In addition, the pressure drop caused by the first blocking portion is smaller without causing a significant increase in the power consumption of the coolant supply pump.

[0045] Although it is shown and described above that the first blocking portion is provided in both the cooling liquid distribution area of ​​the anode plate and the cooling liquid distribution area of ​​the cathode plate, the present application is not limited thereto, but may also have various changes. For example, the first blocking portion may be provided in one, two or three of the four cooling liquid distribution areas formed on the inner surface of the anode plate and the cathode plate, and the effect of the present application may still be achieved to a certain extent or completely. For example, when the cooling liquid distribution areas on the anode plate and the cathode plate are greatly different, the first blocking portion may be provided only in the cooling liquid distribution area of ​​the anode plate or the cathode plate.

[0046] In summary, according to an embodiment of the present application, a first blocking portion may be provided in at least one coolant distribution area, and the first blocking portion extends along the extension direction of the coolant distribution channel connected to the at least one coolant distribution area, so that a portion of the coolant flowing in the at least one coolant distribution area is changed by the first blocking portion to flow along the above extension direction. It is understandable that the first blocking portion is provided in the two coolant distribution areas on the anode plate and the cathode plate that are connected to the coolant inlet, so that the uniform distribution of the coolant can be better achieved.

[0047] like Figure 8 and Fig. 9 As shown, the first blocking portion 71 may extend from a first side of the coolant distribution area 58 toward a second side of the coolant distribution area 58 opposite to the first side, and the first blocking portion 71 is spaced apart from the second side, wherein the first side is closer to the coolant inlet 53 than the second side. In this way, the first blocking portion 71 may facilitate the coolant to flow into the middle coolant channel and allow a certain amount of coolant to flow into the side coolant channels.

[0048] In order to allow more coolant to flow into the middle coolant channel, the first blocking portion 71 may be disposed at a position corresponding to the middle position of the coolant distribution channel 59 (which is connected to the coolant distribution area 58 where the first blocking portion 71 is located), but the application is not limited to this, and the position may be changed according to the specific structure of the coolant distribution channel 59. For example, the first blocking portion may be disposed closer to the upstream or downstream).

[0049] It should be noted that in Figures 8 to 11 In the embodiment, a second blocking portion 72 spaced apart from the first blocking portion 71 may be provided in the coolant distribution area 58 and upstream of the first blocking portion 71, the second blocking portion 72 extends from the second side of the coolant distribution area 58 toward the first side, and the second blocking portion 72 is spaced apart from the first side of the coolant distribution area 58. Therefore, the second blocking portion 72 can change the flow direction of a portion of the coolant, so that more coolant is changed by the first blocking portion 71 to flow along the extension direction of the coolant distribution channel 59 and flow into the middle coolant channel, thereby making the distribution of the coolant more uniform.

[0050] According to an embodiment of the present application, the second blocking portion 72 may be disposed at a position of the coolant distribution area 58 corresponding to an edge position of the connected coolant distribution channel 59 close to the coolant inlet 53, so that the coolant changes its flow direction before entering the corresponding coolant distribution channel 59, and then is changed by the downstream first blocking portion 71 to flow along the extension direction of the coolant distribution channel 59. In addition, the first blocking portion 71 and the second blocking portion 72 may be disposed parallel to each other, so that the second blocking portion 72 can both change the flow direction of the coolant as much as possible and reduce the pressure drop as much as possible.

[0051] In order to minimize the effect of the first blocking portion 71 and the second blocking portion 72 on the pressure drop of the coolant channels on both sides, the distance between the first blocking portion 71 and the second side of the coolant distribution area 58 and the distance between the second blocking portion 72 and the first side of the coolant distribution area 58 can be configured to be one half to one third of the extension length of the first blocking portion 71 and the second blocking portion 72, respectively.

[0052] It should be pointed out that although the first blocking portion 71 and the second blocking portion 72 are illustrated above, the present application is not limited to this configuration, but may be provided with 1, 2, 3 or more blocking portions, as long as these blocking portions can allow more coolant to flow into the middle coolant channel, make the coolant distribution more uniform, and minimize the pressure drop, they can be appropriately adjusted under the guidance of the inventive concept of the present application.

[0053] In order to further reduce the pressure drop of the coolant entering the middle coolant channel 57, as shown in FIG. Fig.12 As shown in the partial cross-sectional view in FIG. 1 , in the cooling liquid distribution area 58, the anode plate 50 and the cathode plate 60 can be respectively arranged to be gradually inclined from the first side to the second side, so that the height of the cooling liquid distribution area 58 gradually decreases from the first side to the second side, for example, the height d1 close to the first side is greater than the height d2 away from the first side. Therefore, when the cooling liquid flows in the cooling liquid distribution area 58, for example, a portion of the cooling liquid flowing in the cooling liquid distribution area 58 of the anode plate 50 can flow directly to the cooling liquid distribution channel 59 (such as the cooling liquid distribution channel 59 of the cathode plate 60) in a certain flow direction and speed. Fig.12 As shown by the downward slanting arrow in the figure, instead of all the coolant flowing on one side of the anode plate 50 turning 90 degrees twice to reach the coolant distribution channel 59 of the cathode plate 60, the pressure drop of the coolant flowing into the middle coolant distribution channel 59 can be further reduced, and the distribution uniformity of the coolant can be further improved.

[0054] It should be noted that although Figures 8 to 10 , it is shown that the first blocking part 71 and the second blocking part 72 are provided in the cooling liquid distribution area at the second end of the anode plate and the cathode plate, but because the second end is set as the cooling liquid outlet end in the above embodiment, the first blocking part 71 and the second blocking part 72 may not be provided in other embodiments, and only the corresponding blocking parts are provided at the cooling liquid inlet end. However, in order to facilitate the change of the flow direction of the cooling liquid at any time, the second end of the anode plate and the cathode plate may be provided with the same structure as the first end.

[0055] In addition, in the coolant distribution area 58 of the anode plate 50 and the cathode plate 60, inwardly protruding and dispersedly arranged protrusions 61 can also be provided to allow the coolant discharged from the coolant inlet to be further distributed in the coolant distribution area, but the flow direction of the coolant cannot be significantly changed.

[0056] like Fig.13 As shown, in the bipolar plate formed according to the above structure, the flow distribution in the coolant channel is more uniform, wherein the flow in the coolant channel on both sides is substantially the same as the flow in the middle coolant channel, or slightly reduced.

[0057] Based on the improved bipolar plate described above, the existing electrochemical cell stack can be improved. Specifically, according to an exemplary embodiment of the present application, an improved electrochemical cell stack can be provided, which may include a first bipolar plate, a membrane electrode assembly, and a second bipolar plate, wherein the anode plate of the first bipolar plate and the cathode plate of the second bipolar plate face each other, and the membrane electrode assembly is disposed between the first bipolar plate and the second bipolar plate, wherein each of the first bipolar plate and the second bipolar plate is a bipolar plate as described above. In this way, the electrochemical cell stack of the present application can achieve uniform coolant distribution, improve cooling effect, and improve working stability and durability.

[0058] The present application has been described in detail above in conjunction with specific embodiments. Obviously, the above description and the embodiments shown in the accompanying drawings should be understood as exemplary and do not constitute a limitation to the present application. For those skilled in the art, various modifications or changes can be made to the present application without departing from the spirit of the present application, and these modifications or changes do not depart from the scope of the present application.

Claims

1. A bipolar plate (100) for an electrochemical cell stack, characterized in that: The bipolar plate (100) comprises: An anode plate (50) and a cathode plate (60) stacked on each other, each of the anode plate (50) and the cathode plate (60) having a first end, a second end opposite to the first end, and a body portion located between the first end and the second end, wherein each of the anode plate (50) and the cathode plate (60) comprises: coolant ports disposed at the first end and the second end; a coolant channel (57) provided on an inner surface of the body portion; a coolant distribution area (58) disposed on an inner surface of the body portion and in communication with the coolant port; and a coolant distribution channel (59) provided on an inner surface of the body portion and communicating with the coolant channel (57), wherein the coolant distribution channel (59) is inclined relative to a flow direction of the coolant discharged from or entering the coolant port; wherein the cooling liquid distribution area (58) of the anode plate (50) is in communication with the cooling liquid distribution channel (59) of the cathode plate (60) located at the same end, and the cooling liquid distribution area (58) of the cathode plate (60) is in communication with the cooling liquid distribution channel (59) of the anode plate (50) located at the same end; and A first blocking portion (71) is provided in at least one coolant distribution area (58), and the first blocking portion (71) extends along an extension direction of the coolant distribution channel (59) connected to the at least one coolant distribution area (58), so that a portion of the coolant flowing in the at least one coolant distribution area (58) is changed by the first blocking portion (71) to flow along the extension direction.

2. The bipolar plate (100) according to claim 1, characterized in that The first blocking portion (71) extends from a first side of the at least one coolant distribution area (58) toward a second side of the at least one coolant distribution area (58) opposite to the first side, and the first blocking portion (71) is spaced apart from the second side, the first side being closer to the coolant port than the second side.

3. The bipolar plate (100) according to claim 2, characterized in that: The first blocking portion (71) is provided at a position of the at least one coolant distribution area (58) corresponding to a middle position of the coolant distribution channel (59) with which it is communicated.

4. The bipolar plate (100) according to claim 2 or 3, characterized in that: A second blocking portion (72) spaced apart from the first blocking portion (71) is further provided within the at least one coolant distribution area (58) and upstream of the first blocking portion (71); the second blocking portion (72) extends from the second side of the at least one coolant distribution area (58) toward the first side, and the second blocking portion (72) is spaced apart from the first side.

5. The bipolar plate (100) according to claim 4, characterized in that: The second blocking portion (72) is provided at a position of the at least one coolant distribution area (58) corresponding to an edge position of the connected coolant distribution channel (59) close to the coolant port.

6. The bipolar plate (100) according to claim 4, characterized in that: The first blocking portion (71) and the second blocking portion (72) are arranged parallel to each other.

7. The bipolar plate (100) according to claim 4, characterized in that: The distance between the first blocking portion (71) and the second side of the at least one coolant distribution area (58) and the distance between the second blocking portion (72) and the first side of the at least one coolant distribution area (58) are respectively one-half to one-third of the extension length of the first blocking portion (71) and the second blocking portion (72).

8. The bipolar plate (100) according to claim 1, characterized in that In the at least one coolant distribution area (58), the anode plate (50) and the cathode plate (60) are arranged to be gradually inclined from a first side of the at least one coolant distribution area (58) toward a second side of the at least one coolant distribution area (58), so that the height of the at least one coolant distribution area (58) gradually decreases from the first side toward the second side, and the first side is closer to the coolant port than the second side.

9. The bipolar plate (100) according to claim 1, characterized in that: A first reaction gas channel corresponding to the cooling liquid channel (57) and a first reaction gas distribution channel corresponding to the cooling liquid distribution channel (59) are provided on the outer surface of the anode plate (50), a second reaction gas channel corresponding to the cooling liquid channel (57) and a second reaction gas distribution channel corresponding to the cooling liquid distribution channel (59) are provided on the outer surface of the cathode plate (60), and a first gas port and a second gas port are provided on both sides of the cooling liquid port, respectively, the first gas port is communicated with the first reaction gas channel and the first reaction gas distribution channel, and the second gas port is communicated with the second reaction gas channel and the second reaction gas distribution channel.

10. An electrochemical cell stack, characterized in that: The electrochemical cell stack comprises: a first bipolar plate and a second bipolar plate, wherein the anode plate of the first bipolar plate and the cathode plate of the second bipolar plate face each other; and a membrane electrode assembly, wherein the membrane electrode assembly is disposed between the first bipolar plate and the second bipolar plate; Wherein, each of the first bipolar plate and the second bipolar plate is a bipolar plate (100) according to any one of claims 1 to 9.

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