Battery pack, multi-cell stack and method for controlling amount of liquid in battery pack

Abstract

The invention relates to a battery pack, a multi-cell stack and a method for controlling the amount of liquid in the battery pack, the battery pack comprises an anode plate, a first diffusion layer, a membrane electrode, a second diffusion layer and a cathode plate which are stacked from bottom to top, the surface, facing the anode plate, of the cathode plate is provided with a gas channel, and the anode plate comprises a substrate; the gas flow channel is arranged in the first direction; the liquid flow channel is formed from the bottom surface of the gas flow channel to the interior of the substrate and is arranged along the second direction; the liquid discharging channel is formed from the side wall of the base plate to the interior of the base plate and arranged in the third direction, and the liquid discharging channel communicates with the liquid flow channel; according to the voltage change of the membrane electrode and the water discharge condition of the liquid discharge channel, whether the membrane is in a dry state or a flooded state is judged so as to replenish water or discharge water to the liquid flow channel, the problem of dry or flooded membrane in the membrane electrode can be solved in time, membrane damage caused by sharp voltage rise is avoided, and the service life of the membrane electrode is prolonged. The thickness of the membrane electrode is not increased, so that the energy consumption is prevented from being increased.

Description

Technical Field

[0001] This invention relates to the field of electrochemical technology, and particularly to a battery pack, a multi-cell stack, and a method for controlling the amount of liquid within the battery pack. Background Technology

[0002] Electrochemical compression has attracted increasing attention in recent years due to its ability to achieve isothermal compression and high compression efficiency. In electrochemical compression, hydrogen gas undergoes catalytic oxidation at the anode to produce protons (H₂O). + The protons release electrons and, driven by an external DC electric field, selectively migrate through the proton exchange membrane to the cathode. Simultaneously, electrons are transported to the cathode via an external circuit. At the cathode, the migrated protons recombine with the electrons, reducing them to generate high-pressure hydrogen gas. This process achieves direct electrochemical compression and pressurized output of hydrogen gas.

[0003] To ensure the conductivity of the proton exchange membrane, water is required during the electrochemical compression process. The hydrogen gas entering the anode needs a certain level of humidity, but humidity control is difficult to detect or quantify precisely. Insufficient humidity will cause the membrane to dry out, hindering the transfer of hydrogen protons to the cathode and causing a sharp voltage increase, generating significant heat, rising temperature, and increasing energy consumption. If the humidity reaches a certain level, it can damage the membrane. Conversely, excessive water entering the anode can flood the membrane interface where the electrochemical reaction occurs, also causing a voltage increase. Both membrane dryness and flooding cause voltage increases, and these increases are difficult to distinguish. Furthermore, the structure of electrochemical compression itself makes real-time monitoring of membrane dryness or flooding challenging. In other words, water management during electrochemical compression is a phenomenon that is difficult to detect or explain directly or indirectly.

[0004] Existing technologies address membrane drying by developing self-humidifying membranes with water retention capabilities, but this also increases membrane impedance, voltage, and energy consumption to some extent, and the water retention capacity is affected by the water retention function.

[0005] Therefore, in the electrochemical compression process, it is necessary to determine the state of the membrane electrode and promptly address the issues of water flooding or membrane drying. Summary of the Invention

[0006] This invention provides a battery pack, a multi-cell stack, and a method for controlling the amount of liquid in the battery pack. It can promptly and intuitively determine whether the membrane is in a dry or flooded state based on the voltage changes of the membrane electrode and the water discharge from the drainage channel, thereby controlling water replenishment or drainage to solve the problems of membrane dryness or flooding.

[0007] This invention provides a battery pack, comprising: an anode plate, a first diffusion layer, a membrane electrode, a second diffusion layer, and a cathode plate stacked from bottom to top, wherein the cathode plate has a gas channel on its surface facing the anode plate; The anode plate includes: substrate; A gas flow channel is disposed on the surface of the substrate, and the gas flow channel is disposed along a first direction; A liquid flow channel is formed from the bottom of the gas flow channel into the substrate, and the liquid flow channel is arranged along a second direction; A drain channel is formed from the side wall of the substrate into the substrate, the drain channel is arranged in a third direction, and the drain channel is in communication with the liquid flow channel; The drain channel is connected to a control valve, which is connected to a water supply and drainage pipeline. The system determines whether the membrane is in a dry or flooded state based on the voltage change of the membrane electrode and the water discharge from the drain channel, and then replenishes or drains the liquid flow channel accordingly.

[0008] In one embodiment, the drainage channel has a drainage port at one end near the sidewall of the substrate, and the other end inside the substrate is sealed.

[0009] In one embodiment, the drain port is connected to a transparent tube. When a voltage increase is detected, the membrane electrode is determined to be either dry or flooded based on the flow of water into the transparent tube, so as to control the control valve to replenish or drain water.

[0010] In one embodiment, when draining water, a water level of 1-3 cm is maintained inside the transparent tube to seal the gas.

[0011] In one embodiment, the drainage channel is located at a position of 1 / 2 to 2 / 3 of the substrate thickness.

[0012] In one embodiment, the drainage channel is provided with multiple channels, which are evenly spaced along a first direction.

[0013] The present invention also provides a multi-cell stack, comprising: a plurality of battery packs as described in claims 1-6 stacked together, wherein the two ends of the battery packs are respectively provided with an anode plate and a cathode plate, wherein the cathode plates of adjacent battery packs close to each other are integrally disposed with the anode plates to form bipolar plates.

[0014] The present invention also provides a method for controlling the amount of liquid in the above-mentioned battery pack, comprising: Determine whether the voltage of the membrane electrode increases; If so, then determine whether the membrane electrode is in a dry state or a flooded state; If the membrane is dry, control the control valve to open the water supply and drainage pipes to replenish water into the membrane. If the area is flooded, the control valve is used to open the water supply and drainage pipes to drain the water from the drainage channel.

[0015] In one embodiment, one end of the drainage channel is connected to a transparent tube, and the membrane electrode is determined to be in a dry state or a flooded state based on the flow of water into the transparent tube.

[0016] In one embodiment, the method for determining whether the membrane electrode is in a dry state or a flooded state is as follows: When no liquid is detected flowing into the transparent tube, it is determined that the anode plate is short of water and the membrane electrode is in a dry state. When water is detected continuously entering the transparent tube from the drainage channel, it is determined that there is too much water in the anode plate and the membrane electrode is in a water-flooded state.

[0017] Compared with the prior art, the advantages of the present invention are that a drain channel is provided inside the substrate of the anode plate, the drain channel is connected to the liquid flow channel, and a control valve is connected to the outlet of the drain channel. When the voltage of the membrane electrode is detected to rise, the membrane electrode is judged to be in a dry or flooded state according to the water discharge of the drain channel, thereby controlling the control valve to replenish or drain water from the liquid flow channel, so as to solve the problem of membrane dryness or flooding in the membrane electrode in time, avoid membrane damage caused by a sharp increase in voltage, and the thickness of the membrane electrode will not increase, thus avoiding an increase in energy consumption. Attached Figure Description

[0018] The invention will now be described in more detail with reference to embodiments and the accompanying drawings.

[0019] Figure 1 This is a schematic diagram of the battery pack structure according to Embodiment 1 of the present invention; Figure 2 This is a perspective view of the anode plate in the battery pack of Embodiment 1 of the present invention; Figure 3 This is a three-dimensional sectional view of the anode plate in the battery pack of Embodiment 1 of the present invention; Figure 4 This is a cross-sectional view of the anode plate in the battery pack of Embodiment 1 of the present invention; Figure 5 This is a schematic diagram of the structure of the multi-cell stack according to Embodiment 2 of the present invention; Figure 6 This is a schematic diagram of the bipolar plate structure in the multi-cell stack of the present invention, Embodiment 2; Figure 7 yes Figure 6 A schematic diagram of a bipolar plate where the anode plate and cathode plate are separated. Figure 8 This is a schematic diagram of water replenishment and drainage for a multi-battery stack according to Embodiment 3 of the present invention.

[0020] Figure label: 1. Anode plate; 11. Substrate; 12. Gas flow channel; 13. Liquid flow channel; 14. Drainage channel; 15. Drainage port; 16. Transparent tube; 17. Metal tube; 2. Control valve; 3. Drainage and water supply pipelines; 4. Cathode plate; 41. Gas passage; 5. Anode plate; 6. First diffusion layer; 7. Membrane electrode; 8. Second diffusion layer; 9. Cathode end plate; 10. Battery pack. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0022] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0023] Furthermore, the use of terms such as "first" and "second" in this invention is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. When the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed by this invention.

[0024] Electrochemical compression is the process by which hydrogen gas is catalytically oxidized at the anode to produce protons (H2O). + The protons release electrons and, driven by an external DC electric field, selectively migrate through the proton exchange membrane to the cathode. Simultaneously, electrons are transported to the cathode via an external circuit. At the cathode, the migrated protons recombine with the electrons, reducing them to generate high-pressure hydrogen gas. This process achieves direct electrochemical compression and pressurized output of hydrogen gas.

[0025] To ensure the conductivity of the proton exchange membrane, water is required during the electrochemical compression process. The hydrogen gas entering the anode needs a certain level of humidity, but humidity control is difficult to detect or quantify precisely. Insufficient humidity will cause the membrane to dry out, hindering the transfer of hydrogen protons to the cathode and causing a sharp voltage increase, generating significant heat, rising temperature, and increasing energy consumption. If the humidity reaches a certain level, it can damage the membrane. Conversely, excessive water entering the anode can flood the membrane interface where the electrochemical reaction occurs, also causing a voltage increase. Both membrane dryness and flooding cause voltage increases, and these increases are difficult to distinguish. Furthermore, the structure of electrochemical compression itself makes real-time monitoring of membrane dryness or flooding challenging. In other words, water management during electrochemical compression is a phenomenon that is difficult to detect or explain directly or indirectly.

[0026] Existing technologies address membrane drying by developing self-humidifying membranes with water retention capabilities, but this also increases membrane impedance, voltage, and energy consumption to some extent, and the water retention capacity is affected by the water retention function.

[0027] Therefore, in the electrochemical compression process, it is necessary to determine the state of the membrane electrode and promptly address the issues of water flooding or membrane drying.

[0028] This invention provides a technical solution that can easily detect membrane dryness or flooding and replenish or drain water in a timely manner.

[0029] Example 1 like Figure 1 As shown, the present invention provides a battery pack 10, including an anode plate 1, a first diffusion layer 6, a membrane electrode 7, a second diffusion layer 8 and a cathode plate 4 stacked from bottom to top, wherein a gas channel 41 is provided on the surface of the cathode plate 4 facing the anode plate 1 for hydrogen gas to pass through.

[0030] like Figures 2 to 4 As shown, the anode plate 1 includes a substrate 11, a gas flow channel 12 disposed on the surface of the substrate 11 for hydrogen to pass through, a liquid flow channel 13 disposed in the substrate 11 for supplying water into the anode plate 1 for use in the electrochemical compression process, and a drain channel 14 disposed in the substrate 11, which is connected to the liquid flow channel 13 to replenish or drain water from the liquid flow channel 13.

[0031] In this embodiment, the gas channel 12 is disposed on the surface of the substrate 11 along a first direction, the liquid channel 13 is opened from the bottom of the gas channel 12 into the substrate 11, the liquid channel 13 is disposed along a second direction, the second direction is perpendicular to the first direction, and the drain channel 14 is opened from the side wall of the substrate 11 into the substrate 11, the drain channel 14 is disposed along a third direction, the third direction is perpendicular to the first and second directions. Through the vertically disposed drain channel 14 and liquid channel 13, excessive water in the gas channel 12 and liquid channel 13 can be effectively drained to avoid flooding.

[0032] Furthermore, the drainage channel 14 is connected to the control valve 2, which is connected to the water supply and drainage pipeline 3. Based on the voltage change of the membrane electrode 7 and the water discharge from the drainage channel 14, it is determined whether the membrane is in a dry or flooded state, and water is supplied to or drained from the liquid flow channel 13 accordingly. Specifically, when an increase in the voltage of the membrane electrode 7 is detected, the water discharge from the drainage channel 14 is used to determine whether the membrane electrode 7 is in a dry or flooded state. This allows the control valve 2 to supply or drain water from the liquid flow channel 13, promptly resolving the problem of membrane dryness or flooding within the membrane electrode 7, preventing membrane damage caused by a rapid increase in voltage. Moreover, the drainage and water supply structure of this invention eliminates the need for an additional water-retaining layer, and the membrane thickness remains unchanged, thus avoiding increased energy consumption.

[0033] In one embodiment, the drain channel 14 has a drain outlet 15 at one end near the sidewall of the substrate 11, and the other end is sealed. In this embodiment, the drain channel 14 extends from the sidewall of the substrate 11 into the substrate 11, but does not penetrate the other sidewall of the substrate 11; that is, the drain channel 14 is a blind hole. In another embodiment, for ease of processing, a through hole can be formed in the substrate 11, and the other end of the through hole is sealed with a plug.

[0034] like Figure 4 As shown, in a preferred embodiment, the drain port 15 is connected to a transparent tube 16. When an increase in the voltage of the membrane electrode 7 is detected, the state of the membrane electrode 7—whether it is dry or flooded—is determined based on the flow of water into the transparent tube 16, thereby controlling the control valve 2 to replenish or drain water. In this embodiment, the drain port 15 is connected to a metal tube 17 through a tapered threaded hole. The metal tube 17 is as short as possible, and the end of the metal tube 17 furthest from the drain port 15 is connected to the transparent tube 16 via a flange. The transparent tube 16 is a bent tube, bent downwards, allowing observation of whether water continuously flows into it, thus providing a direct visual assessment of the state of the membrane electrode 7. The lower end of the transparent tube 16 is connected to the control valve 2.

[0035] It should be noted that if a sudden voltage increase occurs, it generally indicates membrane dryness or flooding. In this case, observe whether water continuously flows into the transparent tube 16 to determine whether the membrane is dry or flooded. If no water flows into the transparent tube 16, it indicates a lack of water in the anode plate 1, and the membrane electrode 7 is dry. In this case, open control valve 2 to the water replenishment mode and introduce atomized water vapor or steam into the drainage channel 14. Adjust the flow rate according to the operating temperature to promptly resolve the membrane dryness issue. If water continuously flows into the transparent tube 16 from the drainage channel 14, it indicates excessive water in the anode plate 1, and the membrane electrode 7 is flooded. In this case, open control valve 2 to the drainage mode to drain the excess water from the transparent tube 16, leaving a 1-3 cm liquid level at the bottom for gas sealing. This will promptly resolve the flooding issue. Once the voltage of the membrane electrode 7 drops to a normal level, stop water replenishment or drainage.

[0036] By installing a transparent tube 16 on the outlet side of the drainage channel 14, the present invention can observe the drainage situation in the anode plate 1 in a timely manner. Combined with the voltage change, it can be determined whether the membrane is in a dry state or a flooded state. The water supply or drainage can be controlled by the control valve 2 to solve the problem of membrane dryness or flooding in a timely manner.

[0037] Since the anode plate 1 is a low-pressure section within a battery pack 10, the implementation risk is relatively low by setting up a drainage channel 14 within the anode plate 1. When a single cell or battery stack is placed vertically, with the anode plate 1 at the bottom, in the event of flooding, water will flow along the drainage channel 14 into the transparent tube 16 due to gravity. The outflow of water from the drainage channel 14 can be directly observed through the transparent tube 16. The accumulated water can be drained by the control valve 2, ensuring the safe operation of the single cell or battery stack.

[0038] For existing water-retaining self-humidifying membranes, the increased thickness due to the addition of a water-retaining layer, or the decrease in conductivity or increase in voltage due to the addition of other resin components, all lead to increased energy consumption. However, this invention modifies the anode plate 1 without increasing the membrane thickness, thus avoiding the problems associated with water-retaining self-humidifying membranes and solving the water management problem in electrochemical compression.

[0039] In one embodiment, when draining, a water level of 1-3 cm is maintained in the transparent tube 16 to seal the gas in the anode plate 1, ensuring that hydrogen does not enter the pipeline below the control valve 2, thus serving as a liquid seal.

[0040] In one embodiment, the drain channel 14 is located at 1 / 2 to 2 / 3 of the thickness of the substrate 11, so that the anode plate 1 will not collapse or deform.

[0041] like Figures 2 to 4As shown, in one embodiment, multiple drainage channels 14 are provided, evenly spaced along a first direction. It should be noted that multiple gas channels 12 are spaced along the first direction on the surface of the substrate 11, and multiple liquid channels 13 are spaced along a second direction within each gas channel 12. Thus, the liquid channels 13 are arranged in rows (along a third direction) and columns (along the first direction) within the substrate 11. Drainage channels 14 are located at the bottom of the liquid channels 13 and are arranged along a third direction. Therefore, one drainage channel 14 can connect to the bottom of multiple liquid channels 13 in the third direction, replenishing or draining water from the multiple liquid channels 13 in that row. In this embodiment, the number of drainage channels 14 is the same as the number of rows of liquid channels 13 in the third direction, ensuring that each liquid channel 13 can connect to its corresponding drainage channel 14.

[0042] In one embodiment, the drain outlet 15 of each drain channel 14 is connected to a transparent tube 16 and a control valve 2, thus allowing targeted replenishment or drainage of water into a specific row of liquid channels 13. In another embodiment, all drain channels 14 can be connected to the same transparent tube 16 and control valve 2 for overall replenishment or drainage.

[0043] In this embodiment, the thickness of the substrate 11 is 1.5cm to 2.0cm, and the drain channel 14 is located 0.75cm to 1.0cm away from the surface of the substrate 11 where the gas flow channel 12 is located. The drain channel 14 is located at the middle of the thickness of the substrate 11, so that the anode plate 1 will not collapse or deform due to the opening of the drain channel 14. The diameter of the liquid flow channel 13 is 0.3mm to 0.5mm, and the diameter of the drain channel 14 is 1mm to 2mm. After data analysis and experimental verification, the anode plate 1 of this embodiment can withstand a pressure of 20MPa, which meets the usage requirements.

[0044] The battery pack 10 of the present invention can be used in a single cell. The single cell includes a stacked anode plate 5, a battery pack 10 and a cathode plate 9. The first diffusion layer 6 and the second diffusion layer 8 are used to transport the medium and provide a certain support for the membrane electrode 7. The first diffusion layer 6 and the second diffusion layer 8 are made of a metal with a certain porosity, such as titanium felt.

[0045] When the single cell is placed vertically, the anode plate 1 is at the bottom. When flooding occurs, due to gravity, the water will flow along the drain channel 14 into the transparent tube 16. The water flowing out of the drain channel 14 can be observed directly through the transparent tube 16. The accumulated water can be drained by the control valve 2 to ensure the safe operation of the single cell.

[0046] Furthermore, since the anode plate 1 is a low-pressure section, the drainage channel 14 is set inside the anode plate 1, which reduces the implementation risk.

[0047] Example 2 like Figure 5 and Figure 6 As shown, the present invention provides a multi-cell stack, including multiple battery packs 10 stacked together. Each battery pack 10 has an anode end plate 5 and a cathode end plate 9 at both ends. Each battery pack 10 includes an anode plate 1, a first diffusion layer 6, a membrane electrode 7, a second diffusion layer 8, and a cathode plate 4 stacked from bottom to top. The cathode plates 4 of adjacent battery packs 10 are integrally formed with the anode plates 1 to form a bipolar plate. The cathode plates 4 and anode plates 1 share a substrate 11 to form a bipolar plate, which can reduce the thickness of the multi-cell stack and strengthen the anode plate 1. Even if a drain channel 14 is opened inside the anode plate 1, sufficient support can be guaranteed to avoid collapse or deformation.

[0048] In this embodiment, two battery packs 10 are arranged between the anode plate 5 and the cathode plate 9. In each battery pack 10, the anode plate 1 is located at the bottom and the cathode plate 4 is located at the top. The structure of the anode plate 1 is the same as in Embodiment 1, and will not be described again. A gas channel 41 is provided on the surface of the cathode plate 4 facing the anode plate 1.

[0049] The drain channels 14 of the anode plates 1 of multiple battery packs 10 are connected to the water supply and drainage pipes 3 through different control valves 2. Based on the voltage change of the inner membrane electrode 7 of the battery pack 10 and the flow of water from the drain channel 14 into the transparent tube 16, it is determined whether the membrane is in a dry state or a flooded state. Then, one or more control valves 2 are controlled to open the water supply and drainage pipes 3 to replenish or drain water, so as to solve the problem of membrane dryness or flooding.

[0050] Example 3 like Figure 8 As shown in the figure, this embodiment demonstrates the water replenishment and drainage structure of a multi-cell stack. The drainage channels 14 of the anode plates 1 in the three cell stacks 10 are respectively connected to the control valves 2 through transparent tubes 16. The control valves 2 are connected to the water replenishment and drainage pipes 3. Based on the voltage change of the membrane electrode 7 inside the cell stack 10 and the flow of water from the drainage channels 14 into the transparent tubes 16, it is determined whether the membrane is in a dry state or a flooded state. Thus, one or more control valves 2 are controlled to open the water replenishment and drainage pipes 3 to replenish or drain water, so as to solve the problem of membrane dryness or flooding.

[0051] Example 4 The present invention also provides a method for controlling the amount of liquid in a battery pack 10, comprising: Determine whether the voltage of membrane electrode 7 increases; If so, then determine whether membrane electrode 7 is in a dry state or a flooded state; If the membrane is dry, control valve 2 opens the water supply and drainage pipe 3 to replenish water into the liquid flow channel 13; If the area is flooded, control valve 2 opens the water supply and drainage pipe 3 to drain the water from the drainage channel 14.

[0052] It should be noted that the voltage of membrane electrode 7 is measured by an external circuit connected to membrane electrode 7. When the voltage of membrane electrode 7 continuously increases or increases sharply, it indicates that membrane dryness or flooding has occurred.

[0053] In one embodiment, one end of the drain channel 14 of the anode plate 1 is connected to the transparent tube 16. Based on the flow of water from the drain channel 14 into the transparent tube 16, it is determined whether the membrane electrode 7 is in a dry state or a flooded state.

[0054] In one embodiment, the method for determining whether the membrane electrode 7 is in a dry state or a flooded state is as follows: When no liquid is detected flowing into the transparent tube 16, it is determined that there is a lack of water in the anode plate 1 and the membrane electrode 7 is in a dry state. When water is detected continuously flowing into the transparent tube 16 from the drainage channel 14, it is determined that there is too much water in the anode plate 1 and the membrane electrode 7 is in a state of being submerged in water.

[0055] In one embodiment, the following steps are also included: Determine whether the voltage of membrane electrode 7 has dropped to a normal level; If so, then control valve 2 will be closed.

[0056] This invention determines whether the membrane is dry or flooded based on the voltage changes of the membrane electrode and the flow of water into the transparent tube 16. If a sudden voltage increase occurs, it generally indicates membrane dryness or flooding. In this case, observe whether water continues to flow into the transparent tube 16 to determine the state. If no water flows into the transparent tube 16, it is determined to be dry. In this case, open control valve 2 to the water replenishment mode and introduce atomized water vapor or steam into the drainage channel 14. Adjust the flow according to the operating temperature to promptly resolve the membrane dehydration problem. If water continuously flows into the transparent tube 16 while the voltage increases, it is determined to be flooded. In this case, open control valve 2 to the drainage mode to drain excess water from the transparent tube 16, leaving a 1-3 cm liquid level at the bottom for gas sealing. This promptly resolves the flooding problem. Once the voltage of the membrane electrode 7 drops to a normal level, water replenishment or drainage is stopped.

[0057] This invention solves the problem of difficulty in detecting membrane dryness or flooding in the prior art. By observing voltage changes and the flow of water into the transparent tube 16, it is possible to directly detect whether the membrane is dry or flooded. Based on the membrane's condition, the control valve 2 is opened to replenish or drain water, thus resolving the problems of flooding or membrane dryness in a timely manner.

[0058] Although the invention has been described with reference to preferred embodiments, various modifications can be made and components can be replaced with equivalents without departing from the scope of the invention. In particular, the technical features mentioned in the various embodiments can be combined in any manner as long as there is no structural conflict. The invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A battery pack, characterized in that, include: An anode plate, a first diffusion layer, a membrane electrode, a second diffusion layer, and a cathode plate are stacked from bottom to top, and the cathode plate has a gas channel on its surface facing the anode plate. The anode plate includes: substrate; A gas flow channel is disposed on the surface of the substrate, and the gas flow channel is disposed along a first direction; A liquid flow channel is formed from the bottom of the gas flow channel into the substrate, and the liquid flow channel is arranged along a second direction; A drain channel is formed from the side wall of the substrate into the substrate, the drain channel is arranged in a third direction, and the drain channel is in communication with the liquid flow channel; The drain channel is connected to a control valve, which is connected to a water supply and drainage pipeline. The system determines whether the membrane is in a dry or flooded state based on the voltage change of the membrane electrode and the water discharge from the drain channel, and then replenishes or drains the liquid flow channel accordingly.

2. The battery pack according to claim 1, characterized in that, The drainage channel has a drainage port at one end near the side wall of the substrate, and the other end inside the substrate is sealed.

3. The battery pack according to claim 2, characterized in that, The drain port is connected to a transparent tube. When a voltage increase is detected, the membrane electrode is determined to be either dry or flooded based on the flow of water into the transparent tube, so as to control the control valve to replenish or drain water.

4. The battery pack according to claim 3, characterized in that, When draining, a water level of 1-3 cm is maintained inside the transparent tube to seal the gas.

5. The battery pack according to claim 1, characterized in that, The drainage channel is located at 1 / 2 to 2 / 3 of the thickness of the substrate.

6. The battery pack according to claim 1, characterized in that, The drainage channel is provided in multiple ways, and is evenly spaced along the first direction.

7. A multi-cell stack, characterized in that, include: Multiple battery packs as described in claims 1-6 are stacked together, with a positive terminal plate and a negative terminal plate respectively provided at both ends of the battery packs, wherein the cathode plate and the anode plate of adjacent battery packs are integrally formed to form a bipolar plate.

8. A method for controlling the amount of liquid in the battery pack according to claim 1, characterized in that, include: Determine whether the voltage of the membrane electrode increases; If so, then determine whether the membrane electrode is in a dry state or a flooded state; If the membrane is dry, control the control valve to open the water supply and drainage pipes to replenish water into the membrane. If the area is flooded, the control valve is used to open the water supply and drainage pipes to drain the water from the drainage channel.

9. The method according to claim 8, characterized in that, One end of the drainage channel is connected to a transparent tube, and the membrane electrode is judged to be in a dry state or a flooded state based on the flow of water into the transparent tube.

10. The method according to claim 9, characterized in that, The method for determining whether the membrane electrode is in a dry or flooded state is as follows: When no liquid is detected flowing into the transparent tube, it is determined that the anode plate is short of water and the membrane electrode is in a dry state. When water is detected continuously entering the transparent tube from the drainage channel, it is determined that there is too much water in the anode plate and the membrane electrode is in a water-flooded state.

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