Electric pile and electric pile system

Abstract

The invention provides a galvanic pile and a galvanic pile system, the galvanic pile is provided with an anode end plate and a cathode end plate, the anode end plate comprises a first gas inlet channel, a second gas inlet channel and a third gas inlet channel, the first gas inlet channel is arranged on the anode end plate in a penetrating manner and is configured to convey first gas into the galvanic pile; the first exhaust channel is arranged on the anode end plate in a penetrating manner and is configured to exhaust the first gas which is not completely reacted; and the drift diameter is configured to convey at least part of the first gas in the first exhaust channel to the first gas inlet channel. In the galvanic pile and the galvanic pile system provided by the invention, due to the arrangement of the drift diameter, a pipeline in the process of conveying the first gas to the galvanic pile forms a three-way pipeline, and hydrogen circulation and recovery in the running process of the galvanic pile can be realized through the devices. The energy utilization rate of the fuel cell is improved, and meanwhile, the operation stability of a galvanic pile system is improved.

Description

Technical Field

[0001] The present disclosure relates to the field of fuel cell technology, and in particular to a fuel cell stack and a fuel cell stack system. Background Art

[0002] A fuel cell is an electrochemical power generation device that directly converts chemical energy into electrical energy. It has high energy conversion efficiency and is pollution-free and noise-free. It is becoming a new generation of ideal energy utilization. As fuel cell technology gradually matures, the commercial application of fuel cells has broad development prospects. Among them, air-cooled fuel cells use air as a cooling medium and are mainly used in miniaturized application scenarios such as electric two-wheeled vehicles and drones. In miniaturized application scenarios, the utilization rate of hydrogen has a great impact on the energy efficiency of the entire hydrogen fuel cell system. At the same time, the adaptability of the hydrogen fuel cell system to low-temperature environments also determines whether it can be applied and promoted in low-temperature areas in the north. Summary of the invention

[0003] The purpose of this disclosure is to provide a battery stack and a battery stack system to solve the technical problems in the related technology. The specific solution is as follows:

[0004] A first aspect of an embodiment of the present disclosure provides a fuel cell stack having an anode end plate and a cathode end plate, the anode end plate comprising: a first air inlet channel, penetrating the anode end plate, configured to transport a first gas into the fuel cell stack; a first exhaust channel, penetrating the anode end plate, configured to discharge the first gas that has not completely reacted; a path, wherein both ends of the path are respectively connected to the first air inlet channel and the first exhaust channel, configured to transport at least part of the first gas in the first exhaust channel to the first air inlet channel.

[0005] In some embodiments, the through-path is disposed inside the anode end plate.

[0006] In some embodiments, the first air inlet passage includes: a diameter change, located inside the first air inlet passage, configured to increase the flow rate of the first gas.

[0007] In some embodiments, the fuel cell stack further includes: a first air inlet located at an end of the first air inlet channel away from the cathode end plate, and a cross-sectional diameter of the first air inlet is larger than a cross-sectional diameter of the variable diameter.

[0008] In some embodiments, the through diameter is connected to the variable diameter, and the variable diameter is smaller than the through diameter.

[0009] The faster the flow rate, the lower the pressure; the faster the flow rate, the lower the pressure.

[0010] In some embodiments, a cross-sectional diameter of the passage is smaller than a cross-sectional diameter of the first air inlet or the first air outlet.

[0011] In some embodiments, the cross-sectional diameter of the passage is 2-30 mm.

[0012] In a second aspect of the present disclosure, a fuel cell stack system is provided, comprising: the fuel cell stack provided in the first aspect of the present disclosure; a first gas source connected to a first air inlet of the fuel cell stack and configured to supply a first gas to the fuel cell stack; and a first solenoid valve disposed between the first gas source and the first air inlet.

[0013] In some embodiments, the fuel cell stack system also includes: a recovery tank connected to the first exhaust channel of the fuel cell stack and configured to recover the first gas that has not completely reacted in the fuel cell stack; a second solenoid valve disposed between the recovery tank and the first exhaust channel and configured to adjust the pressure of the first gas discharged from the fuel cell stack, the recovery tank having a preset pressure value, and in response to the gas pressure in the recovery tank reaching the preset pressure value, the second solenoid valve opens to allow the first gas to flow normally.

[0014] In some embodiments, the preset pressure value is smaller than the difference between the working pressure of the anode of the fuel cell stack and the pressure drop value of the anode flow channel in the fuel cell stack.

[0015] Compared with the related art, the above solution of the embodiment of the present disclosure has at least the following beneficial effects:

[0016] In the battery stack and battery stack system provided by the present disclosure, the setting of the through-path enables the pipeline of the first gas to form a three-way pipeline during the process of being transported to the battery stack. Through the above device, the circulation and recovery of hydrogen during the operation of the battery stack can be realized, which improves the energy utilization rate of the fuel cell and the stability of the operation of the battery stack system.

[0017] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings herein are incorporated into the specification and constitute a part of the specification, showing embodiments consistent with the present disclosure, and together with the specification, are used to explain the principles of the present disclosure. Obviously, the drawings described below are only some embodiments of the present disclosure, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0019] Figure 1 It is a schematic structural diagram of an anode terminal plate according to an exemplary embodiment.

[0020] Figure 2 yes Figure 1 The cross-sectional view with AA as the section.

[0021] Figure 3 It is a schematic structural diagram of a fuel cell system according to an exemplary embodiment. Description of the drawings:

[0023] Anode end plate 100, first air inlet 101, first air inlet channel 110, diameter change 111, first exhaust channel 120, diameter 130;

[0024] The fuel cell stack system 200 , the first gas source 210 , the first solenoid valve 220 , the recovery tank 230 , the second solenoid valve 240 , and the automatic discharge device 250 . DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solutions and advantages of the present disclosure clearer, the present disclosure will be further described in detail below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present disclosure, rather than all of the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present disclosure.

[0026] The terms used in the embodiments of the present disclosure are only for the purpose of describing specific embodiments, and are not intended to limit the present disclosure. The singular forms "a", "said" and "the" used in the embodiments of the present disclosure and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings, and "multiple" generally includes at least two, and other quantifiers are similar.

[0027] It should be understood that, although the terms first, second, third, etc. may be used to describe in the disclosed embodiments, these descriptions should not be limited to these terms. These terms are only used to distinguish the described objects. For example, without departing from the scope of the disclosed embodiments, the first may also be referred to as the second, and similarly, the second may also be referred to as the first. In addition, the terms "first", "second", "third", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0028] It should be understood that the term "and / or" used in this article is only a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship. The singular forms "a", "the" and "the" are also intended to include the plural forms, unless the context clearly indicates other meanings.

[0029] In the description of the present disclosure, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0030] It should also be noted that the term "includes", "comprising" or any other variation thereof is intended to cover non-exclusive inclusion, so that a commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprising a ..." do not exclude the existence of other identical elements in the commodity or device including the elements.

[0031] In related technologies, in miniaturized application scenarios of fuel cells, the first solenoid valve is generally used to control the opening or closing time of the hydrogen outlet channel end, and the pulse exhaust of the hydrogen side is achieved by adjusting the switching frequency of the first solenoid valve. The exhausted hydrogen is directly released into the atmosphere, and the utilization rate of hydrogen is low. The utilization rate of hydrogen has a great impact on the energy efficiency of the entire hydrogen fuel cell system. At the same time, the adaptability of the hydrogen fuel cell system to low-temperature environments also determines whether it can be applied and promoted in low-temperature areas.

[0032] Therefore, the present disclosure provides a fuel cell stack having an anode end plate and a cathode end plate, the anode end plate comprising: a first air inlet channel, penetrating the anode end plate, configured to transport a first gas into the fuel cell stack; a first exhaust channel, penetrating the anode end plate, configured to discharge the first gas that has not been completely reacted; and a through hole, arranged inside the anode end plate, configured to transport at least part of the first gas in the first exhaust channel to the first air inlet channel.

[0033] The fuel cell stack provided by the present disclosure has a through diameter, and the through diameter is arranged to form a three-way pipeline of the ventilation pipeline of the fuel cell stack. Through the above device, the circulation and recovery of the first gas during the operation of the fuel cell stack can be realized, thereby improving the energy utilization rate of the fuel cell and improving the stability of the operation of the fuel cell system.

[0034] The optional embodiments of the present disclosure are described in detail below with reference to the accompanying drawings.

[0035] The first aspect of the embodiment of the present disclosure provides an embodiment of the present disclosure provides a battery stack, which is a device that directly converts chemical energy into electrical energy. Structurally, the battery stack is mainly composed of multiple battery cells connected in series, and these battery cells are connected by components such as bipolar plates, just like connecting many small batteries together. An anode end plate 100 and a cathode end plate are respectively arranged on both sides of the bipolar plate.

[0036] In some embodiments, Figure 1 As shown, a first air inlet channel 110 and a first exhaust channel 120 are provided on the anode end plate 100. The first air inlet channel 110 is provided through the anode end plate 100 and is configured to transport the first gas into the fuel cell stack; the first exhaust channel 120 is provided through the anode end plate 100 and is configured to discharge the first gas that has not reacted completely.

[0037] In some embodiments, the first gas is hydrogen, which is delivered to the interior of the fuel cell stack via the first air inlet passage 110, undergoes an oxidation reaction with the membrane electrode inside the fuel cell stack, and hydrogen molecules lose electrons to become hydrogen ions. These electrons reach the cathode through an external circuit, forming an electric current.

[0038] In some embodiments, a second air inlet channel and a second exhaust channel are provided through the cathode end plate, wherein the second air inlet channel is provided through the cathode end plate and is configured to transport a second gas into the fuel cell stack; the second exhaust channel is provided through the cathode end plate and is configured to discharge the incompletely reacted second gas.

[0039] In some embodiments, the second gas is oxygen, which is delivered to the interior of the fuel cell stack via the second air inlet passage, undergoes a reduction reaction with the membrane electrode inside the fuel cell stack, and combines with hydrogen ions and electrons from the anode to generate water.

[0040] In some embodiments, the first air inlet channel 110 includes a diameter change 111, which is located inside the first air inlet channel 110 and is configured to increase the flow rate of the first gas. The first air inlet channel 110 also includes a first air inlet 101, which is located at one end of the first air inlet channel 110 away from the cathode end plate. Figure 2 As shown, the cross-sectional diameter of the first air inlet 101 is significantly larger than the cross-sectional diameter of the variable diameter 111. When the first gas flows to the variable diameter 111, the flow rate of the first gas will increase due to the narrowing of the flow tube diameter, thereby improving the transportation speed of the first gas and stably supplying the first gas to the interior of the fuel cell stack.

[0041] In some embodiments, the anode end plate 100 further includes a through-path 130. The through-path 130 may be disposed inside the anode end plate 100 and configured to connect the first exhaust channel 120 with the first intake channel 110. The through-path 130 may transport at least a portion of the first gas in the first exhaust channel 120 to the first intake channel 110, so that the first gas re-enters the interior of the fuel cell stack via the first intake channel 110.

[0042] It should be separately explained that the present disclosure does not specifically limit the position of the through-path 130 , and the through-path 130 can be set inside the anode end plate 100 , or outside the anode end plate 100 , or at any other position that can connect the first air intake channel 110 with the first exhaust channel 120 .

[0043] In some embodiments, Figure 2 As shown, the two ends of the through-path 130 are respectively a first end and a second end, the first end is connected to the first air intake channel 110, and the second end is connected to the first exhaust channel 120. Specifically, the first end of the through-path 130 is connected to the variable diameter 111, and in response to the first gas being discharged from the stack through the first exhaust channel 120, at least part of the first gas flows to the variable diameter 111 through the through-path 130, so that the first gas re-enters the interior of the stack from the first air intake channel 110 to participate in a new round of chemical reaction.

[0044] In some embodiments, the cross-sectional diameter of the through-path 130 is larger than the cross-sectional diameter of the variable diameter 111, and the cross-sectional diameter of the first air inlet 101 is larger than the cross-sectional diameter of the variable diameter 111. In response to the first gas flowing out of the first exhaust channel 120, at least part of the first gas flows to the variable diameter 111 through the through-path 130. In this process, since the cross-sectional diameter of the through-path 130 is larger than the cross-sectional diameter of the variable diameter 111, the fluid pressure of the first gas when flowing through the variable diameter 111 is reduced, the flow rate is accelerated, and the pressure is reduced, so that the first gas can stably flow from the through-path 130 to the variable diameter 111. In addition, since the cross-sectional diameters of the first air inlet channel 110 and the first exhaust channel 120 are significantly larger than the variable diameter 111, the first gas can stably flow to the variable diameter 111 through the through-path 130 when flowing out of the first exhaust channel 120.

[0045] In some embodiments, the input pressure of the first gas when entering the first inlet channel 110 is P1, the pressure of the first gas after passing through the diameter changer 111 is P2, the density of the first gas is ρ, the flow rate of the first gas when entering the first inlet channel 110 is v1, and the flow rate of the first gas after passing through the diameter changer 111 is v2; the gravitational potential energy ρgh of the first gas in the pipeline is unchanged, then according to the Bernoulli equation formula, it can be obtained:

[0046]

[0047] Assume that the flow rate of the first gas in the pipeline is V; the diameter of the pipeline is d1, and the diameter at the variable diameter position is d2;

[0048]

[0049] Bring ② and ③ into ①:

[0050]

[0051] By moving the items, you can get:

[0052]

[0053] Assume d2 = kd1, where k is the diameter variation coefficient, and the relationship between pressure change and diameter variation coefficient is as follows:

[0054]

[0055] The relationship between the cross-sectional diameter of the variable diameter 111 and the cross-sectional diameter of the first air intake pipe 110 satisfies the above formula.

[0056] In the second aspect of the present disclosure, a fuel cell stack system 200 is provided, comprising: the fuel cell stack provided in the first aspect of the present disclosure; and further comprising a first gas source 210, the first gas source 210 being connected to the first gas inlet 101 of the fuel cell stack, and a first solenoid valve 220 being provided between the first gas source 210 and the first gas inlet 101, for controlling the speed at which the first gas source 210 supplies the first gas into the fuel cell stack. During the operation of the fuel cell stack, in response to the first solenoid valve 220 being in an open state, the first gas source 210 supplies the first gas to the fuel cell stack, so that the first gas acts on the chemical reaction in the fuel cell stack.

[0057] In some embodiments, the stack system 200 further includes: a recovery tank 230, which is disposed outside the stack, and the recovery tank 230 is connected to the first exhaust channel 120 of the stack, and is configured to recover the first gas that has not completely reacted in the stack. Specifically, the first gas that has not completely reacted in the stack will be discharged from the first exhaust channel 120 to the recovery tank 230.

[0058] In some embodiments, the stack system 200 further includes a second solenoid valve 240, which is disposed between the recovery tank 230 and the first exhaust channel 120 and is configured to adjust the pressure of the first gas discharged from the stack, wherein, in response to the stack being in working condition, the second solenoid valve 240 may be in a pulse discharge mode. Pulse discharge can accurately adjust the discharge amount of the first gas by controlling the frequency, width and amplitude of the pulse. Compared with the continuous discharge mode, pulse discharge can reduce unnecessary energy consumption and avoid continuous discharge while meeting the emission requirements of the stack system 200. On the other hand, compared with the continuous discharge mode which is always in the open state, the continuous friction and wear between components are reduced, which helps to extend the service life of the second solenoid valve 240.

[0059] When the second solenoid valve 240 is opened, the first gas inside the fuel cell stack flows into the recovery tank 230, causing the flow rate of the first gas at the passage 130 to increase and the pressure to decrease, thereby causing part of the first gas in the first exhaust channel 120 to flow into the first intake channel 110. In this way, partial first gas circulation can be achieved to reduce energy waste.

[0060] In some embodiments, the second solenoid valve 240 may also be disposed in the recovery tank 230 , and configured to adjust the pressure in the recovery tank 230 , maintain the pressure in the recovery tank 230 stable, and ensure the normal operation of the stack system 200 .

[0061] In some embodiments, the gas inside the recovery tank 230 has a preset pressure value, and the recovery tank 230 also includes an automatic discharge device 250. In response to the gas pressure in the recovery tank 230 reaching the preset pressure value, the automatic discharge device 250 is started to ensure the normal flow of the first gas in the fuel cell system 200. The first gas recovered in the recovery tank 230 can be used for low-temperature start-up of the fuel cell or other application requirements, such as: reducing the open circuit voltage under open circuit conditions, extending the service life of the fuel cell, etc.

[0062] In some embodiments, in order to ensure that the first gas that has not completely reacted in the stack can be normally discharged into the recovery tank 230, the preset gas pressure value of the recovery tank 230 is less than the difference between the anode working pressure of the stack and the pressure drop value of the anode flow channel in the stack. The difference between the anode working pressure of the stack and the pressure drop value of the anode flow channel in the stack determines the maximum pressure in the recovery tank 230.

[0063] It should be noted that the pressure drop value, also called pressure drop or pressure loss, refers to the pressure drop value caused by various resistances during the flow of the fluid, such as pipeline friction, pipe resistance, equipment resistance, etc. For example, when the fluid flows into one end of the pipeline, due to the friction of the inner wall of the pipeline on the fluid, the energy of the fluid will be lost, resulting in a drop in pressure. If the pressure at the inlet end of the fluid is 10MPa and the pressure at the outlet end is 8MPa, then the pressure drop value of this section of the pipeline is 2MPa.

[0064] In some embodiments, the difference between the working pressure of the anode of the fuel cell stack and the pressure drop value of the anode flow channel of the bipolar plate in the fuel cell stack and the cross-sectional diameter of the path 130 jointly determine the flow rate of the first gas circulation when the second solenoid valve 240 is opened; the cross-sectional diameter of the path 130 should satisfy: when the second solenoid valve 240 is opened, the pressure drop value in the path 130 is greater than the pressure drop value of the anode flow channel of the bipolar plate in the fuel cell stack.

[0065] In some embodiments, when the cross-sectional diameter of the through-path 130 is 2-30 mm, it is more suitable for the circulation of the first gas. If the cross-sectional diameter of the through-path 130 is less than 2 mm, the circulation of the first gas is likely to be limited, resulting in the waste of excess first gas and the failure to achieve the purpose of re-reaction; if the cross-sectional diameter of the through-path 130 is greater than 30 mm, it is easy for the first gas to flow along the through-path 130 to the first exhaust channel 120 during the process of the first gas entering the fuel cell stack, resulting in a waste of resources. In addition, due to the large cross-sectional diameter of the through-path 130, the first gas in the first exhaust channel 120 may not be able to re-enter the first intake channel 110 through the through-path 130, and the purpose of re-reaction cannot be achieved. Preferably, the cross-sectional diameter of the through-path 130 is 5 mm; 10 mm; 15 mm; 20 mm; 25 mm.

[0066] In some embodiments, the preset pressure value in the recovery tank 230 determines the flow rate of the recovered first gas. In response to the larger the preset pressure value, the faster the flow rate of the first gas is discharged; in response to the smaller the preset pressure value, the slower the flow rate of the first gas is discharged.

[0067] In summary, the fuel cell stack and fuel cell stack system 200 provided by the present disclosure have an innovative anode end plate 100. The setting of the through-path 130 enables the pipeline of the first gas to form a three-way pipeline during the transportation to the fuel cell stack. Through the above device, the circulation and recovery of hydrogen during the operation of the fuel cell stack can be realized. The energy utilization rate of the fuel cell stack is improved, and the stability of the operation of the fuel cell stack system 200 is improved. In addition, a recovery tank 230 is provided in the fuel cell stack system 200, which can collect the first gas that has not been completely reacted to act on the energy source or other application scenarios of the low-temperature startup of the fuel cell stack.

[0068] The specific structure, working principle, and beneficial effects of the fuel cell stack and fuel cell stack system 200 provided in the embodiments of the present disclosure may refer to the fuel cell stack and fuel cell stack system 200 described in any of the above embodiments, and will not be elaborated here.

[0069] Finally, it should be noted that the various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other. For the system or device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part description.

[0070] The above embodiments are only used to illustrate the technical solutions of the present disclosure, rather than to limit them. Although the present disclosure has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present disclosure.

Claims

1. A battery stack having an anode terminal plate and a cathode terminal plate, characterized in that: The anode terminal plate comprises: A first air inlet channel is provided through the anode end plate and is configured to transport a first gas into the fuel cell stack; A first exhaust channel is provided through the anode end plate and is configured to exhaust the first gas that has not been completely reacted; The through path has two ends respectively connected to the first air intake channel and the first exhaust channel, and is configured to transport at least a portion of the first gas in the first exhaust channel to the first air intake channel.

2. The battery stack according to claim 1, characterized in that: The through-path is arranged inside the anode end plate.

3. The battery stack according to claim 1, characterized in that: The first air inlet passage comprises: The variable diameter is located inside the first air inlet passage and is configured to increase the flow rate of the first gas.

4. The battery stack according to claim 3, characterized in that: Also includes: The first air inlet is located at one end of the first air inlet passage away from the cathode end plate, and the cross-sectional diameter of the first air inlet is larger than the cross-sectional diameter of the variable diameter.

5. The battery stack according to claim 3, characterized in that: The through diameter is communicated with the variable diameter, and the cross-sectional diameter of the through diameter is larger than the cross-sectional diameter of the variable diameter.

6. The battery stack according to claim 4, characterized in that: The cross-sectional diameter of the through-path is smaller than the cross-sectional diameter of the first air inlet or the first air outlet.

7. The battery stack according to claim 1, characterized in that: Also includes: The cross-sectional diameter of the through-path is 2-30 mm.

8. A battery stack system, characterized in that: include: The battery stack according to any one of claims 1 to 7; a first gas source connected to the first gas inlet of the fuel cell stack and configured to supply a first gas to the fuel cell stack; The first solenoid valve is arranged between the first gas source and the first gas inlet.

9. The battery stack system according to claim 8, characterized in that: Also includes: A recovery tank, connected to the first exhaust channel of the fuel cell stack, configured to recover the first gas that has not been completely reacted in the fuel cell stack; A second solenoid valve is disposed between the recovery tank and the first exhaust channel and is configured to adjust the pressure of the first gas discharged from the stack. The recovery tank has a preset pressure value. In response to the gas pressure in the recovery tank reaching the preset pressure value, the second solenoid valve is opened to allow the first gas to flow normally.

10. The battery stack system according to claim 9, characterized in that: The preset pressure value is smaller than the difference between the working pressure of the anode of the fuel cell stack and the pressure drop value of the anode flow channel in the fuel cell stack.

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