Fuel stack and fuel cell system with same
By incorporating drainage channels and flow guiding structures into the fuel cell stack, the problem of poor liquid water drainage at the blind end of the fuel cell stack was solved, achieving efficient liquid water drainage and a lightweight design for the fuel cell stack, thus ensuring the stable operation of the fuel cell system.
Patent Information
- Application Number
- CN202520028076.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-02
- Publication Date
- 2025-12-30
- Estimated Expiration
- 2035-01-02
AI Technical Summary
In existing fuel cell stacks, the drainage of liquid water at the blind end is ineffective, and current technologies struggle to effectively remove liquid water, thus affecting the normal operation of the fuel cell stack.
Multiple drainage ports are set between bipolar plates and membrane electrode assemblies in the fuel stack to form a drainage channel. The liquid inlet is close to the bipolar plate on the blind end side and connected to the gas outlet channel through a flow guiding structure. The Venturi effect and Bernoulli's law are used to achieve smooth discharge of liquid water. The cross-section of the drainage channel is designed to be circular or elliptical to avoid stress concentration. Seals are arranged around the drainage channel to ensure sealing.
Effectively draining liquid water from the blind end of the fuel cell stack simplifies the structure, reduces weight, improves the drainage effect of the fuel cell stack, and ensures the normal operation and stable performance of the fuel cell system.
Smart Images
Figure CN223743690U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to fuel cell technology field especially relates to a fuel stack. BACKGROUND
[0002] The fuel stack is mainly composed of bipolar plates and membrane electrode assemblies, and the membrane electrode assembly is a key core component of fuel cell power generation. In the fuel stack structure, each bipolar plate and each membrane electrode assembly is provided with a cathode gas inlet hole, a cathode gas outlet hole, an anode gas inlet hole, an anode gas outlet hole, a cooling liquid inlet hole and a cooling liquid outlet hole.
[0003] Among them, the cathode gas inlet holes on each bipolar plate and each membrane electrode assembly are connected in series to form a cathode gas inlet channel. The cathode gas outlet holes on each bipolar plate and each membrane electrode assembly are connected in series to form a cathode gas outlet channel, which is used for oxygen outflow. The anode gas inlet holes on each bipolar plate and each membrane electrode assembly are connected in series to form an anode gas inlet channel. The anode gas outlet holes on each bipolar plate and each membrane electrode assembly are connected in series to form an anode gas outlet channel, which is used for hydrogen outflow. The cooling liquid inlet holes on each bipolar plate and each membrane electrode assembly are connected in series to form a cooling liquid inlet channel. The cooling liquid outlet holes on each bipolar plate and each membrane electrode assembly are connected in series to form a cooling liquid outlet channel.
[0004] In the operation of the fuel stack, the liquid water generated by the stack reaction is usually discharged with the gas through the anode gas outlet channel or the cathode gas outlet channel. In some fuel stack structures, a thin tube is inserted into the anode gas outlet channel or the cathode gas outlet channel to drain water. However, in the above-mentioned ways, for the liquid water on the blind end side of the fuel stack, the liquid water is forcibly blown out by the gas, the liquid water is dispersed, and the drainage effect is poor. By inserting a thin tube to drain water, the drainage resistance is large, and the drainage effect is not ideal. Therefore, it is urgent to design a fuel stack structure to facilitate the drainage of liquid water on the blind end side of the fuel stack. SUMMARY
[0005] Therefore, the utility model aims at providing a fuel stack to facilitate the drainage of liquid water on the blind end side of the fuel stack.
[0006] To achieve the above-mentioned purpose, the technical scheme of the utility model is as follows:
[0007] A fuel stack has a plurality of bipolar plates stacked together, and a membrane electrode assembly arranged between adjacent bipolar plates;
[0008] The plurality of bipolar plates includes an inlet side bipolar plate, at least one intermediate bipolar plate and a blind end side bipolar plate arranged in sequence, and the inlet side bipolar plate, each membrane electrode assembly and each intermediate bipolar plate are provided with a drainage port;
[0009] The drainage ports on the gas inlet side bipolar plate, and each of the membrane electrode assemblies and the intermediate bipolar plates are connected in series to form a drainage channel, and an inlet of the drainage channel is arranged close to the blind end side bipolar plate, and the inlet is communicated with an outlet channel in the fuel cell stack.
[0010] Further, the blind end side bipolar plate and / or one of the intermediate bipolar plates adjacent to the blind end side bipolar plate is provided with a flow guide structure, and the inlet is communicated with the outlet channel through the flow guide structure.
[0011] Further, the flow guide structure comprises a first flow guide groove arranged on the blind end side bipolar plate, and / or the flow guide structure comprises a second flow guide groove arranged on one of the intermediate bipolar plates adjacent to the blind end side bipolar plate.
[0012] Further, the cross-sectional area of each of the drainage ports gradually decreases in the direction from the blind end side bipolar plate to the gas inlet side bipolar plate.
[0013] Further, the cross section of each of the drainage ports is circular or elliptical.
[0014] Further, a sealing member is arranged between adjacent bipolar plates and surrounds the drainage channel.
[0015] Further, at least one of the bipolar plates among the adjacent bipolar plates is provided with a sealing groove, and the sealing member is arranged in the sealing groove.
[0016] Further, the outlet channel comprises an outlet hole arranged through each of the bipolar plates and each of the membrane electrode assemblies; and the inlet of the drainage channel is communicated with the outlet hole on the blind end side bipolar plate.
[0017] Further, the outlet channel comprises a first outlet channel for hydrogen gas outflow and a second outlet channel for oxygen gas outflow, and the drainage channel is a plurality of channels corresponding to the first outlet channel and the second outlet channel respectively.
[0018] Compared with the prior art, the present application has the following advantages:
[0019] The fuel cell stack, through the drainage port arranged on the inlet side bipolar plate, each membrane electrode assembly and each intermediate bipolar plate, the drainage ports on the inlet side bipolar plate, each membrane electrode assembly and each intermediate bipolar plate are connected in series to form a drainage channel, and the liquid inlet of the drainage channel is arranged close to the blind end side bipolar plate, and the liquid inlet is communicated with the gas outlet channel in the fuel cell stack, so that the liquid water on the blind end side of the fuel cell stack in the stack reaction process can flow into the drainage channel through the gas outlet channel, and is discharged to the outside of the stack through the drainage channel, thereby facilitating the discharge of the liquid water on the blind end side of the fuel cell stack, and the drainage channel is relatively simple in structure, and the weight of the fuel cell stack can be reduced to some extent, facilitating the lightweight design of the fuel cell stack.
[0020] In addition, the flow guide structure on the blind end side bipolar plate is communicated with the gas outlet channel through the liquid inlet of the drainage channel, which can guide the liquid water on the blind end side of the fuel cell stack in the stack reaction process to flow from the gas outlet channel to the drainage channel, and further facilitate the discharge of the liquid water generated in the stack reaction. The cross-sectional area of each drainage port is reduced in the direction of the inlet side bipolar plate along the blind end side bipolar plate, that is, the flow cross section of the drainage channel is reduced in the direction of the liquid outlet along the liquid inlet of the drainage channel, and at this time, the Venturi effect and Bernoulli's law can be utilized to form a step pressure difference in the drainage channel, so that the liquid water can be effectively and smoothly discharged to the outside of the stack.
[0021] Secondly, the cross section of each drainage port is circular or elliptical, which is simple in structure and easy to prepare and form, and compared with rectangular or triangular shapes, stress concentration points can be avoided. The sealing element is arranged between the adjacent bipolar plates, so that the sealing element is arranged around the drainage channel, thereby ensuring the sealing property between the adjacent drainage ports on the adjacent bipolar plates, so that the leakage of the drainage channel can be prevented. The sealing groove is arranged on at least one of the adjacent bipolar plates, so that the sealing element can be arranged and positioned on the bipolar plate, thereby further ensuring the sealing property between the adjacent drainage ports.
[0022] In addition, the liquid inlet of the drainage channel is communicated with the gas outlet hole on the blind end side bipolar plate, which is convenient for structural arrangement, and is beneficial to the timely flow of the liquid water on the blind end side of the fuel cell stack into the drainage channel, thereby facilitating the timely discharge of the liquid water. The drainage channel is communicated with the first gas outlet channel and the second gas outlet channel one by one, so that the liquid water in the first gas outlet channel and the second gas outlet channel can be discharged respectively, and the drainage effect is further improved.
[0023] Another purpose of the utility model is to provide a fuel cell system, which is provided with the fuel cell stack.
[0024] The fuel cell system of the utility model, through adopting the fuel cell stack as above, can benefit the liquid water on the blind end side of the fuel cell stack in the stack reaction to be discharged outside the fuel cell stack, thereby benefiting the normal operation and performance stability of the fuel cell system. BRIEF DESCRIPTION OF DRAWINGS
[0025] The accompanying drawings, which form a part of this patent, are included to provide a further understanding of the application and are incorporated herein in their entirety. The drawings are not intended to limit the scope of the application but rather serve as an exemplification of the various embodiments of the application. In the drawings:
[0026] Figure 1 The structure schematic view of the first visual angle of the fuel cell stack described in the utility model embodiment;
[0027] Figure 2 The structure schematic view of the second visual angle of the fuel cell stack described in the utility model embodiment;
[0028] Figure 3 The structure schematic view of the drainage channel described in the utility model embodiment;
[0029] Figure 4 The structure schematic view of the gas inlet side bipolar plate described in the utility model embodiment;
[0030] Figure 5 The structure schematic view of the blind end side bipolar plate described in the utility model embodiment;
[0031] Figure 6 The Figure 4 Enlarged view of A part;
[0032] Figure 7 The Figure 4 Enlarged view of B part;
[0033] BRIEF DESCRIPTION OF DRAWINGS
[0034] 1, gas port end plate; 2, blind end end plate;
[0035] 21, gas inlet side bipolar plate; 22, intermediate bipolar plate; 23, blind end side bipolar plate;
[0036] 211, cathode gas inlet hole; 212, cathode gas outlet hole; 213, anode gas inlet hole; 214, anode gas outlet hole; 215, cooling liquid outlet hole; 216, cooling liquid inlet hole; 2101, sealing groove; 2102, sealing element;
[0037] 10, drainage port; 20, first flow guide groove; 100, drainage channel; 1001, liquid inlet; 1002, liquid outlet; 200, gas outlet. DETAILED DESCRIPTION
[0038] It should be noted that the embodiments in the utility model and the features in the embodiments can be combined with each other in the case of no conflict.
[0039] In the description of the utility model, it should be noted that if the terms indicating the orientation or position relationship such as "upper", "lower", "inner", "outer" and the like appear, they are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the utility model and simplifying the description, and therefore cannot be understood as limiting the utility model. In addition, if the terms "first", "second" and the like appear, they are also only for the description purpose, and cannot be understood as indicating or implying relative importance.
[0040] In addition, in the description of the utility model, unless otherwise explicitly limited, the terms "mounting", "connection", "connecting", "connecting piece" should be understood in a broad sense. For example, it can be fixed connection, or detachable connection, or integrally connected; it can be mechanical connection, or electrical connection; it can be directly connected, or indirectly connected through intermediate medium, or the communication inside two elements. For ordinary skilled in the art, the specific meaning of the above terms in the utility model can be understood in combination with the specific circumstances.
[0041] The utility model will be described in detail below with reference to the drawings and in combination with the embodiments.
[0042] Embodiment one
[0043] The embodiment relates to a fuel cell stack, which is beneficial to discharging liquid water generated in the reaction process of the stack by optimizing the drainage structure.
[0044] In the overall structure, as shown in the figure, Figures 1 to 3 The fuel cell stack of the embodiment has a plurality of bipolar plates stacked together, and a membrane electrode assembly arranged between adjacent bipolar plates.
[0045] The plurality of bipolar plates include an air inlet side bipolar plate 21, at least one intermediate bipolar plate 22 and a blind end side bipolar plate 23 arranged in sequence, and the air inlet side bipolar plate 21, each membrane electrode assembly and each intermediate bipolar plate 22 are provided with a drainage port 10. In the stacked state of the plurality of bipolar plates, the air inlet side bipolar plate 21, and the drainage ports 10 on each membrane electrode assembly and each intermediate bipolar plate 22 are connected in series to form a drainage channel 100, and the liquid inlet 1001 of the drainage channel 100 is arranged close to the blind end side bipolar plate 23, and the liquid inlet 1001 is communicated with the air outlet channel in the fuel cell stack.
[0046] At this time, in the structure, the water drainage ports 10 on the gas inlet side bipolar plate 21, the membrane electrode assemblies and the intermediate bipolar plates 22 are sequentially connected to form the water drainage channel 100, and the liquid inlet 1001 of the water drainage channel 100 is arranged close to the blind end side bipolar plate 23 and communicates with the gas outlet channel in the fuel cell. In this way, the liquid water on the blind end side of the fuel cell stack can flow into the water drainage channel 100 through the gas outlet channel and be discharged to the outside of the fuel cell stack through the water drainage channel 100, thereby facilitating the discharge of the liquid water on the blind end side of the fuel cell stack. Moreover, the water drainage channel 100 of the embodiment is relatively simple in structure and can also reduce the weight of the fuel cell stack to some extent, thereby facilitating the lightweight design of the fuel cell stack.
[0047] Based on the above overall introduction, in detail, continuing to refer to Figures 1 to 3 In the embodiment, the fuel cell stack includes the gas port end plate 1 and the blind end plate 2 arranged at intervals, and the stack body between the gas port end plate 1 and the blind end plate 2. The stack body is provided with current collecting plates and insulating plates on both sides. The current collecting plates on both sides are connected to the corresponding sides of the stack body. The two insulating plates are respectively arranged between the corresponding side current collecting plate and the gas port end plate 1, and between the corresponding side current collecting plate and the blind end plate 2.
[0048] The stack body includes a plurality of bipolar plates stacked together and membrane electrode assemblies arranged between adjacent bipolar plates. The plurality of bipolar plates includes the gas inlet side bipolar plate 21, at least one intermediate bipolar plate 22 and the blind end side bipolar plate 23 arranged in sequence. In the embodiment, the water drainage ports 10 are arranged on the gas inlet side bipolar plate 21, the membrane electrode assemblies and the intermediate bipolar plates 22. The plurality of water drainage ports 10 are sequentially connected to form the water drainage channel 100 extending along the stacking direction of the bipolar plates. The water drainage channel 100 is arranged close to the gas outlet channel in the fuel cell stack, and the liquid inlet 1001 of the water drainage channel 100 is arranged close to the blind end side bipolar plate 23 and communicates with the gas outlet channel.
[0049] It is worth mentioning that in the embodiment, the water drainage ports 10 are also arranged on the gas port end plate 1 and the current collecting plate close to the gas port end plate 1. The liquid inlet 1001 of the water drainage channel 100 communicates with the gas outlet channel. The liquid outlet 1002 of the water drainage channel 100 communicates with the water drainage ports 10 on the gas port end plate 1 and the water drainage ports 10 on the current collecting plate. In this way, the liquid water generated by the stack reaction is discharged to the outside of the fuel cell stack through the water drainage channel 100, the water drainage ports 10 on the current collecting plate and the water drainage ports 10 on the gas port end plate 1.
[0050] In addition, it is also worth mentioning that Figure 1 and Figure 2Only the gas port end plate 1, the blind end end plate 2, the gas inlet side bipolar plate 21, at least one intermediate bipolar plate 22 and the blind end side bipolar plate 23 are shown, and the membrane electrode assembly, the current collector plate and the insulating plate are not shown. It is also worth mentioning that in this embodiment, among the plurality of bipolar plates, the gas inlet side bipolar plate 21 and the intermediate bipolar plate 22 are completely identical in structure, and the structure of the gas inlet side bipolar plate 21 and the intermediate bipolar plate 22 can be referred to as shown in the following figure. Figure 4
[0051] As a preferred embodiment, in this embodiment, a flow guide structure is provided on the blind end side bipolar plate 23, and the liquid inlet 1001 of the drainage channel 100 is communicated with the gas outlet channel through the flow guide structure. At this time, the flow guide structure can communicate the liquid inlet 1001 of the drainage channel 100 with the gas outlet channel, which can facilitate guiding the liquid water on the blind end side of the fuel cell stack in the stack reaction to flow from the gas outlet channel to the drainage channel 100, thereby further facilitating the discharge of the liquid water generated in the stack reaction.
[0052] In terms of specific structure, the gas outlet channel of this embodiment includes a gas outlet hole 200 arranged through each bipolar plate and each membrane electrode assembly, that is, each bipolar plate and each membrane electrode assembly is provided with a gas outlet hole 200, and the gas outlet holes 200 on each bipolar plate and each membrane electrode assembly are sequentially connected to form the above-mentioned gas outlet channel.
[0053] As shown in the following figure, Figure 5 The flow guide structure of this embodiment includes a first flow guide groove 20 arranged on the blind end side bipolar plate 23, which is specifically communicated with the gas outlet hole 200 formed on the blind end side bipolar plate 23, thereby connecting the drainage channel 100 with the gas outlet channel.
[0054] And in specific implementation, the first flow guide groove 20 is arranged outside the gas outlet hole 200 of the blind end side bipolar plate 23 and is communicated with the gas outlet hole 200 to form a special-shaped hole, which is simple in structure, easy to prepare and form, and has less structural changes to the bipolar plate, and compared with other complex flow guide structures, it is beneficial to save manufacturing cost.
[0055] It is worth mentioning here that in this embodiment, in addition to connecting the liquid inlet 1001 of the drainage channel 100 with the gas outlet channel in the fuel cell stack through the flow guide structure arranged on the blind end side bipolar plate 23, a flow guide structure can also be arranged on one of the intermediate bipolar plates 22 adjacent to the blind end side bipolar plate 23, so that the liquid inlet 1001 of the drainage channel 100 is communicated with the gas outlet hole 200 on the intermediate bipolar plate 22 through the flow guide structure, so that the liquid water on the blind end side of the fuel cell stack can also be discharged outside the fuel cell stack through the drainage channel.
[0056] The flow guide structure on the intermediate bipolar plate 22 can be a second flow guide groove identical to the first flow guide groove 20 on the blind end side bipolar plate 23. Of course, a strip-shaped communication groove can be arranged between the gas outlet hole 200 and the water outlet 10 on the intermediate bipolar plate 22, so that the liquid inlet 1001 of the water outlet channel 100 on the intermediate bipolar plate 22 is in communication with the gas outlet hole 200 through the communication groove, thus realizing the communication between the liquid inlet 1001 of the water outlet channel 100 and the gas outlet channel.
[0057] In addition, it is worth mentioning that in actual application, the size of the fuel cell stack in the stacking direction of the bipolar plate is designed. When the size is small, the blind end side bipolar plate 23 can be arranged as one. When the size is small, the blind end side bipolar plate 23 can also be arranged as a plurality of stacked. When the blind end side bipolar plate 23 is a plurality of stacked, the flow guide groove structure is arranged on each blind end side bipolar plate 23. When the blind end side bipolar plate 23 is one, the flow guide groove structure is arranged on the blind end side bipolar plate 23. Of course, the flow guide groove structure can also be arranged only on the adjacent intermediate bipolar plate 22, or the flow guide groove structure can be arranged on the blind end side bipolar plate 23 and the adjacent intermediate bipolar plate 22. Such arrangement is also feasible.
[0058] In this embodiment, as a preferred, the cross-sectional area of each water outlet 10 gradually decreases in the direction of the blind end side bipolar plate 23 pointing to the gas inlet side bipolar plate 21. Specifically, as shown by the arrow in the direction of the liquid inlet 1001 of the water outlet channel 100 pointing to the liquid outlet 1002, the flow cross section of the water outlet channel 100 is reduced, at this time, by using the Venturi effect and Bernoulli's law, a step pressure difference can be formed in the water outlet channel 100, so that the liquid water can be more effectively and smoothly discharged outside the stack. Figure 3
[0059] And as a further preferred embodiment, in this embodiment, the cross section of each water outlet 10 is circular or elliptical, which is simple in structure and easy to prepare. It can be understood that the cross section of each water outlet 10 can be rectangular or triangular in shape, except for circular or elliptical. Compared with rectangular or triangular shape, circular or elliptical shape can avoid stress concentration points.
[0060] Moreover, in the specific implementation, when the cross-sectional shape of each water outlet 10 is circular, the hole diameter d1 of the liquid inlet 1001 of the water channel 100 is between 5.5 mm and 6.5 mm, and the hole diameter d2 of the liquid outlet 1002 of the water channel 100 is between 2.5 mm and 3.5 mm. Specifically, the hole diameter d1 of the water outlet 10 on the intermediate bipolar plate 22 close to the blind end side bipolar plate 23 is between 5.5 mm and 6.5 mm, and can be specifically set to 5.5 mm, 6 mm, or 6.5 mm. The hole diameter d2 of the water outlet 10 on the gas inlet side bipolar plate 21 is between 2.5 mm and 3.5 mm, and can be specifically set to 2.5 mm, 3 mm, or 3.5 mm. It should be noted here that the difference between the hole diameters of the water outlets 10 on the adjacent bipolar plates should be as small as possible, so that the water channel 100 formed thereby tends to be a smooth conical surface, thereby preventing water accumulation in the water channel 100 and facilitating the complete drainage of the liquid water at the blind end side of the fuel cell stack to the outside of the fuel cell stack.
[0061] Referring to Figures 5 to 7 As shown in the figure, in the embodiment, a sealing member 2102 is arranged around the water channel 100 between the adjacent bipolar plates. The sealing member 2102 can ensure the sealing between the water outlets 10 on the adjacent bipolar plates, thereby preventing leakage of the water channel 100.
[0062] As a further preferred embodiment, in the embodiment, at least one of the adjacent bipolar plates is provided with a sealing groove 2101, and the sealing member 2102 is arranged in the sealing groove 2101. In this way, the arrangement of the sealing member 2102 can be facilitated by the provision of the sealing groove 2101, so that the sealing member 2102 can be better positioned on the bipolar plate, thereby further ensuring the sealing between the adjacent water outlets 10. In the specific implementation, the sealing groove 2101 is arranged around the water outlet 10, and the sealing member 2102 is preferably a sealing ring, which is arranged in the sealing groove 2101 and clamped between the adjacent bipolar plates when the adjacent bipolar plates are stacked and connected, thereby achieving better sealing effect.
[0063] It should be noted that the sealing groove 2101 can be provided only on one of the two adjacent bipolar plates, and it can be understood that the sealing groove 2101 can also be provided on both bipolar plates, and a sealing ring can be arranged in each sealing groove 2101, or a sealing ring can be arranged in the two opposite sealing grooves 2101, so as to ensure the sealing between the adjacent water outlets 10.
[0064] In this embodiment, the gas port end plate 1, the insulation plate, the current collector plate, each bipolar plate and each membrane electrode assembly are provided with an anode gas inlet hole 213, an anode gas outlet hole 214, a cathode gas inlet hole 211, a cathode gas outlet hole 212, a cooling liquid inlet hole 216 and a cooling liquid outlet hole 215. The arrangement of each manifold is as shown in Figure 2 、 Figure 4 and Figure 5 The anode gas inlet hole 213 and the anode gas outlet hole 214 and the cathode gas inlet hole 211 and the cathode gas outlet hole 212 are arranged in a cross-diagonal manner. The cooling liquid inlet hole 216 and the cooling liquid outlet hole 215 are arranged in a length direction of the bipolar plate, the cooling liquid inlet hole 216 is located below the cathode gas inlet hole 211, and the cooling liquid outlet hole 215 is located below the anode gas inlet hole 213. Specifically, in the left side of Figure 4 and Figure 5 from top to bottom, the anode gas inlet hole 213, the cooling liquid outlet hole 215 and the cathode gas outlet hole 212, Figure 4 and Figure 5 from top to bottom, the cathode gas inlet hole 211, the cooling liquid inlet hole 216 and the anode gas outlet hole 214.
[0065] The anode gas inlet hole 213 on the gas port end plate 1, the insulation plate, the current collector plate, each bipolar plate and each membrane electrode assembly is connected in series to form an anode gas inlet channel. The cathode gas inlet hole 211 on the gas port end plate 1, the insulation plate, the current collector plate, each bipolar plate and each membrane electrode assembly is connected in series to form a cathode gas inlet channel. The cooling liquid inlet hole 216 on the gas port end plate 1, the insulation plate, the current collector plate, each bipolar plate and each membrane electrode assembly is connected in series to form a cooling liquid inlet channel. The cooling liquid outlet hole 215 on each bipolar plate and each membrane electrode assembly is connected in series to form a cooling liquid outlet channel.
[0066] In this embodiment, the gas outlet hole 200 that penetrates through each bipolar plate and each membrane electrode assembly includes the anode gas outlet hole 214 provided on each bipolar plate and each membrane electrode assembly, and the cathode gas outlet hole 212 provided on each bipolar plate and each membrane electrode assembly. The anode gas outlet hole 214 on each bipolar plate and each membrane electrode assembly, and the anode gas outlet hole 214 on the gas port end plate 1, the insulation plate and the current collector plate are connected in series to form an anode gas outlet channel, which is used for hydrogen gas to flow out, and the anode gas outlet channel is also a first gas outlet channel. The cathode gas outlet hole 212 on each bipolar plate and each membrane electrode assembly, and the cathode gas outlet hole 212 on the gas port end plate 1, the insulation plate and the current collector plate are connected in series to form a cathode gas outlet channel, which is used for oxygen gas to flow out, and the cathode gas outlet channel is also a second gas outlet channel.
[0067] In actual use, in addition to the reaction of oxygen, protons and electrons to generate water, some side reactions may also occur to generate water. Therefore, as a preferred embodiment, the water discharge channels 100 in this embodiment are in one-to-one correspondence with the first and second gas outlet channels, i.e., the water discharge channels 100 are in one-to-one correspondence with the anode gas outlet channel and the cathode gas outlet channel. At this time, the water discharge channels 100 in one-to-one correspondence with the first and second gas outlet channels are provided, so that the liquid water in the first and second gas outlet channels can be discharged respectively, and the water discharge effect is further improved.
[0068] Specifically, the first and second water discharge ports are arranged on the inlet gas side bipolar plate 21, the membrane electrode assemblies and the intermediate bipolar plates 22 near the anode gas outlet holes 214 and the cathode gas outlet holes 212, and the first flow guide grooves 20 are arranged on the blind end side bipolar plate 23 corresponding to the positions of the cathode gas outlet holes 212 and the anode gas outlet holes 214.
[0069] The plurality of first water discharge ports are connected in series to form a first water discharge channel extending in the stacking direction of the bipolar plates, and the plurality of second water discharge ports are connected in series to form a second water discharge channel extending in the stacking direction of the bipolar plates. The first water discharge channel is in communication with the anode gas outlet channel through the corresponding first flow guide groove 20, and the second water discharge channel is in communication with the cathode gas outlet channel through the corresponding first flow guide groove 20. That is, the first water discharge channel and the second water discharge channel are in communication with the first gas outlet channel and the second gas outlet channel through the corresponding first flow guide grooves 20. In this way, two water discharge paths are formed in the fuel cell stack, so that the liquid water in the first and second gas outlet channels can be discharged outside the fuel cell stack through the second water discharge channel and the first water discharge channel, thereby further improving the water discharge effect.
[0070] The fuel cell stack of this embodiment has the water discharge ports 10 arranged on the inlet gas side bipolar plate 21, the membrane electrode assemblies and the intermediate bipolar plates 22 connected in series to form the water discharge channels 100. This not only has a simple structure and facilitates lightweight design, but also facilitates the discharge of liquid water from the blind end side of the fuel cell stack during the reaction of the fuel cell stack, and has good use effect.
[0071] Embodiment Two
[0072] This embodiment relates to a fuel cell system provided with the fuel cell stack of embodiment one.
[0073] The fuel cell system of this embodiment, by using the fuel cell stack described in embodiment one, can facilitate the discharge of liquid water from the blind end side of the fuel cell stack during the reaction of the fuel cell stack, thereby facilitating the normal operation and performance stability of the fuel cell system.
[0074] The above merely describes preferred embodiments of the present application and is not intended to limit the present application, and any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.
Claims
1.A fuel cell stack, characterized in that: a plurality of bipolar plates are stacked together in the fuel cell stack, and a membrane electrode assembly is arranged between adjacent bipolar plates respectively; the plurality of bipolar plates comprise an inlet side bipolar plate (21), at least one intermediate bipolar plate (22) and a blind end side bipolar plate (23) arranged in sequence, and a drain port (10) is arranged on the inlet side bipolar plate (21), each membrane electrode assembly and each intermediate bipolar plate (22) ; the drain ports (10) on the inlet side bipolar plate (21), each membrane electrode assembly and each intermediate bipolar plate (22) are connected in series to form a drain channel (100), and a liquid inlet (1001) of the drain channel (100) is arranged close to the blind end side bipolar plate (23), and the liquid inlet (1001) is communicated with an exhaust channel in the fuel cell stack. 2.The fuel cell stack according to claim 1, characterized in that: a flow guide structure is arranged on the blind end side bipolar plate (23) and / or one intermediate bipolar plate (22) adjacent to the blind end side bipolar plate (23) ; and the liquid inlet (1001) is communicated with the exhaust channel through the flow guide structure. 3.The fuel cell stack according to claim 2, characterized in that: the flow guide structure comprises a first flow guide groove (20) arranged on the blind end side bipolar plate (23), and / or the flow guide structure comprises a second flow guide groove arranged on one intermediate bipolar plate (22) adjacent to the blind end side bipolar plate (23). 4.The fuel cell stack according to claim 1, characterized in that: the cross-sectional area of each drain port (10) gradually decreases in the direction from the blind end side bipolar plate (23) to the inlet side bipolar plate (21). 5.The fuel cell stack according to claim 4, characterized in that: the cross section of each drain port (10) is circular or elliptical. 6.The fuel cell stack according to claim 1, characterized in that: a sealing member (2102) is arranged around the drain channel (100) between adjacent bipolar plates respectively. 7.The fuel cell stack according to claim 6, characterized in that: at least one of the adjacent bipolar plates is provided with a sealing groove (2101), and the sealing member (2102) is arranged in the sealing groove (2101). 8.The fuel cell stack according to any one of claims 1 to 7, characterized in that: the exhaust channel comprises an exhaust hole (200) arranged through each bipolar plate and each membrane electrode assembly; and the liquid inlet (1001) of the drain channel (100) is communicated with the exhaust hole (200) on the blind end side bipolar plate (23). 9.The fuel cell stack according to claim 8, characterized in that: the exhaust channel comprises a first exhaust channel for hydrogen gas outflow and a second exhaust channel for oxygen gas outflow, and the drain channel (100) is a plurality of channels communicated with the first exhaust channel and the second exhaust channel respectively. 10.A fuel cell system, characterized in that: The fuel cell system is provided with the fuel cell stack according to any one of claims 1 to 9.