Lithium air battery gas circulating pump, control method thereof and power generation system

Abstract

The invention relates to the technical field of electrochemical energy storage, and discloses a lithium air battery gas circulating pump, a control method thereof and a power generation system.The lithium air battery gas circulating pump comprises a pump body used for forming a gas storage cavity, and the pump body is configured to deform under the action of current so as to change the size of the gas storage cavity; the air inlet channel is formed on the pump body, is communicated with the air storage cavity and is used for sucking air; the air outlet channel is formed in the pump body, communicates with the air storage cavity and is used for discharging air; the air inlet element is arranged in the air inlet channel and is configured to control air inlet flow when the volume of the air storage cavity is changed; and the air outlet element is arranged in the air outlet channel and is configured to control the air outlet flow when the volume of the air storage cavity is changed. According to the scheme, a motor and a transmission mechanism are replaced, and energy consumption and operation noise are remarkably reduced; and meanwhile, due to the integrated design, extra assemblies are reduced, the occupied volume is reduced, and the problems that an electric circulating pump is high in energy consumption, large in volume and high in noise in the related technology are solved.

Description

Technical Field

[0001] This application relates to the field of electrochemical energy storage technology, specifically to a lithium-air battery gas circulation pump and its control method, and a power generation system. Background Technology

[0002] Lithium-air batteries achieve charging and discharging through a redox reaction between lithium metal and oxygen in the air. Their theoretical energy density far exceeds that of existing lithium-ion batteries, showing great promise in fields such as new energy vehicles and large-scale energy storage. However, during the actual discharge process of this battery, oxygen transport kinetics hysteresis often occurs on the positive electrode side: the diffusion rate of oxygen in the porous electrode gradually falls below the reaction consumption rate, leading to a decrease in the discharge voltage plateau and limiting the energy output efficiency.

[0003] To ensure the reaction continues, related technologies typically employ the method of introducing excess air into the positive electrode side. While this method is simple and feasible, it results in significant air waste. To further improve utilization, a gas circulation pump is usually installed in the battery's air circuit to achieve air recycling.

[0004] Most gas circulation pumps used in related technologies are electric, relying on the rotation of the electric motor to maintain gas intake and exhaust. These pumps have significant drawbacks: firstly, they consume enormous amounts of energy, reducing the net output efficiency of the lithium-air battery system; secondly, the electric motor and transmission mechanism occupy valuable internal space within the battery system, hindering device miniaturization; and finally, they generate considerable mechanical noise during operation, affecting the user experience and limiting their application scenarios. Summary of the Invention

[0005] This application provides a lithium-air battery gas circulation pump and its control method, as well as a power generation system, to solve the problems of high energy consumption, high noise, and large space occupation of lithium-air battery gas circulation pumps in related technologies.

[0006] In a first aspect, this application provides a lithium-air battery gas circulation pump, comprising: a pump body for forming a gas storage chamber, the pump body being configured to deform under the action of an electric current to change the volume of the gas storage chamber; an inlet channel formed on the pump body and communicating with the gas storage chamber for drawing in gas; an outlet channel formed on the pump body and communicating with the gas storage chamber for discharging gas; an inlet element disposed in the inlet channel and configured to control the inlet airflow when the volume of the gas storage chamber changes; and an outlet element disposed in the outlet channel and configured to control the outlet airflow when the volume of the gas storage chamber changes.

[0007] Beneficial effects: By driving the volume change of the gas storage chamber through direct mechanical deformation of the pump body under the action of electric current, the electric motor and transmission mechanism are replaced, which significantly reduces energy consumption and operating noise. At the same time, the integrated design reduces additional components and compresses the volume, solving the problems of high energy consumption, large size and high noise of electric circulating pumps in related technologies, and realizing efficient, energy-saving, compact and quiet gas circulation.

[0008] In one optional embodiment, the pump body includes: an air inlet support frame for forming the air inlet channel, the air inlet support frame having a gradually expanding structure; an air outlet support frame for forming the air outlet channel, the air outlet support frame having a gradually expanding structure; a first piezoelectric film and a second piezoelectric film, connecting the larger opening end of the air inlet support frame and the larger opening end of the air outlet support frame to form the air storage cavity.

[0009] Beneficial effects: The gradually expanding structure of the inlet and outlet support frames optimizes airflow distribution, reduces turbulence and pressure loss, and improves gas circulation efficiency; the first and second piezoelectric film connecting frames form a gas storage cavity, and the volume change is controlled by precise mechanical deformation, which further reduces energy loss and noise generation, and enhances the stability and response speed of the system.

[0010] In one alternative embodiment, the materials of the first and second piezoelectric films include polyvinylidene fluoride, piezoelectric crystals, or piezoelectric ceramics.

[0011] Beneficial effects: Materials such as polyvinylidene fluoride, piezoelectric crystals, or piezoelectric ceramics have high voltage constants and excellent mechanical toughness, which ensures that the piezoelectric film can efficiently and reliably deform under the action of high-frequency alternating current, reducing energy conversion losses. At the same time, the damping characteristics of the material itself reduce operating noise and extend the service life of the circulating pump, which is conducive to overall energy efficiency improvement and quiet operation.

[0012] In one alternative embodiment, the intake element includes: a first one-way valve disposed in the intake passage and configured to allow gas to flow in when the volume of the gas storage chamber expands.

[0013] Beneficial effects: The first one-way valve is set in the air intake channel and automatically opens by utilizing the negative pressure generated by the expansion of the gas storage chamber, allowing gas to flow in one direction, preventing backflow, simplifying the control logic, and reducing energy waste; this passive control mechanism improves the reliability of gas directional circulation and reduces system complexity and maintenance requirements.

[0014] In one alternative embodiment, the gas outlet element includes a second one-way valve disposed in the gas outlet channel and configured to allow gas to flow out when the volume of the gas storage chamber decreases.

[0015] Beneficial effects: The second one-way valve is located in the gas outlet channel and automatically opens based on the positive pressure generated by the reduction of the gas storage chamber volume, ensuring one-way gas discharge and avoiding gas stagnation and mixing losses; it can also work in conjunction with the first one-way valve to achieve efficient passive airflow control, improve circulation efficiency, and reduce the energy consumption of active control components.

[0016] In one alternative embodiment, the air intake element includes a third piezoelectric film disposed in the air intake channel and configured to allow gas to flow in when the volume of the gas storage chamber expands.

[0017] Beneficial effects: As an active control element, the third piezoelectric film opens or closes the air intake channel by precisely adjusting its deformation through an electric field, providing a more refined airflow modulation capability and reducing frictional wear and noise of mechanical valves; at the same time, the piezoelectric response speed is fast, enabling a more suitable gas supply and further reducing energy consumption and operating noise.

[0018] In one alternative embodiment, the gas outlet element includes a fourth piezoelectric film disposed in the gas outlet channel and configured to allow gas to flow out when the volume of the gas storage chamber decreases.

[0019] Beneficial effects: The fourth piezoelectric film controls the outlet channel through deformation, realizing full piezoelectric-driven airflow management, eliminating the sealing problems and lifespan limitations of mechanical valves; in conjunction with the inlet piezoelectric film, it ensures high precision and consistency of gas circulation, reduces energy leakage and noise, and improves the overall efficiency and reliability of the system.

[0020] In one optional embodiment, the lithium-air battery gas circulation pump further includes a control circuit connected to the inlet element, the outlet element, the first piezoelectric film, and the second piezoelectric film, configured to adjust the voltage or frequency of the alternating current applied to the first piezoelectric film and the second piezoelectric film according to the state of charge or charge / discharge stage of the battery, so that the volume change of the gas storage chamber matches the gas demand.

[0021] Beneficial effects: The control circuit monitors the battery status in real time and dynamically adjusts the AC voltage or frequency applied to the piezoelectric film, so that the volume change of the gas storage chamber precisely matches the gas demand, avoiding energy waste caused by excessive or insufficient gas supply, optimizing the reaction efficiency of the lithium-air battery, and significantly improving the system's energy efficiency and adaptability.

[0022] In one optional implementation, the control circuit is configured to: increase the AC voltage when the battery is discharging to increase the deformation amplitude of the piezoelectric element, thereby increasing the gas supply rate; and decrease the AC voltage when the battery is charging to decrease the deformation amplitude of the piezoelectric element, thereby reducing the gas supply.

[0023] Beneficial effects: Based on intelligent adjustment during battery charging and discharging, it ensures sufficient oxygen supply to maintain battery power output during high demand and reduces gas supply to save energy during low demand. This dynamic optimization not only reduces overall energy consumption but also extends battery cycle life and enhances the stability and economy of the system under different operating conditions.

[0024] Secondly, this application also provides a power generation system, including the lithium-air battery gas circulation pump described in the first aspect or any of the embodiments above; an air supply unit connected to the air intake channel of the lithium-air battery gas circulation pump to supply air to the lithium-air battery gas circulation pump; and a lithium-air battery connected to the air supply unit to receive the air supplied by the air supply unit and / or discharge incompletely reacted air to the air supply unit.

[0025] Beneficial Effects: Through system-level integration, the high-efficiency lithium-air battery gas circulation pump works in conjunction with the air supply unit and the lithium-air battery to achieve closed-loop gas management. The air supply unit directly supplies fresh air to the lithium-air battery gas circulation pump, ensuring a stable oxygen supply. The lithium-air battery, connected to the air supply unit, enables the recovery and reuse of unreacted air, reducing fresh air requirements and peripheral size, thus significantly reducing overall system energy consumption and space occupation. Simultaneously, the piezoelectrically driven lithium-air battery gas circulation pump replaces the traditional electric motor, eliminating mechanical noise at its source, resulting in quiet and stable system operation. This comprehensively solves the problems of high energy consumption, large size, and high noise in related technologies, improving the efficiency and practicality of lithium-air batteries.

[0026] In one optional embodiment, the lithium-air battery includes a positive electrode, a negative electrode, and an exchange membrane; the positive electrode is connected to the lithium-air battery gas circulation pump and the air supply unit for a redox reaction; the negative electrode is ion-conducting with the positive electrode through the exchange membrane for a lithium oxidation reaction.

[0027] Beneficial effects: By directly connecting the positive electrode to the lithium-air battery gas circulation pump and air supply unit, the oxygen supply path is optimized, enabling the oxygen reduction reaction to be rapid and complete, thus improving the battery's output efficiency. The negative electrode is connected to the positive electrode via an exchange membrane, achieving smooth lithium-ion transport and avoiding energy loss and heat accumulation. This structural design enhances the matching degree between the battery and the gas circulation system, making the recovery of unreacted air more precise, further reducing energy consumption and exhaust emissions. At the same time, the compact battery layout reduces the system size, which is conducive to the miniaturization, high efficiency, and low noise operation of the system.

[0028] Thirdly, this application also provides a control method for a lithium-air battery gas circulation pump, comprising: applying alternating current to a piezoelectric element on the pump body of the lithium-air battery gas circulation pump to cause the pump body to deform and change the volume of the gas storage chamber; when the battery is in a discharging state, increasing the alternating current voltage to increase the deformation amplitude of the piezoelectric element to improve the gas supply rate; and when the battery is in a charging state, decreasing the alternating current voltage to decrease the deformation amplitude of the piezoelectric element to reduce the gas supply. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0030] Figure 1 This is a schematic diagram of the structure of a lithium-air battery gas circulation pump according to an embodiment of this application; Figure 2 This is a schematic diagram of a power generation system according to an embodiment of this application; Figure 3 This is a schematic diagram of the working scenario of a power generation system according to an embodiment of this application; Figure 4 This is a schematic flowchart of the lithium-air battery gas circulation pump control method according to an embodiment of this application.

[0031] Explanation of reference numerals in the attached figures: 1. Negative electrode; 2. Exchange membrane; 3. Positive electrode; 4. Air supply unit; 5. Piezoelectric air circulation pump; 6. Inlet channel; 7. First one-way valve; 8. Inlet support frame; 9. First piezoelectric film; 10. Air storage chamber; 11. Second piezoelectric film; 12. Outlet support frame; 13. Second one-way valve; 14. Outlet channel. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0033] In the description of this application, it should be noted that the terms "above" and other designations indicating orientation or positional relationships are based on the orientation or positional relationships shown in the accompanying drawings and are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0034] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0035] Furthermore, the technical features involved in the different embodiments of this application described below can be combined with each other as long as they do not conflict with each other.

[0036] Lithium-air batteries are a novel electrochemical energy storage technology that directly converts chemical energy into electrical energy through an oxidation-reduction reaction between lithium metal and oxygen in the air. They have outstanding advantages such as ultra-high energy density, environmental friendliness, wide availability of raw materials, and excellent low-temperature performance, and are regarded as an important development direction for the next generation of high-energy-density battery systems.

[0037] The core structure of the electrochemical lithium-air battery consists of a lithium metal anode (1), a porous catalytic cathode (3), and an electrolyte system. Its working principle is based on the oxidation reaction of lithium metal at the anode (1) and the reduction reaction of oxygen at the cathode (3). Current is generated through electron transfer in the external circuit, while lithium ions migrate directionally within the electrolyte to complete charge transport, ultimately achieving a highly efficient conversion of chemical energy into electrical energy. Since its theoretical energy density can reach 5-10 times that of existing lithium-ion batteries, it shows broad application prospects in new energy vehicles, drones, and large-scale energy storage.

[0038] In the actual discharge process of lithium-air batteries, the oxygen supply on the positive electrode side (3) often exhibits a transport kinetic lag. That is, as the reaction proceeds, the diffusion rate of oxygen in the porous electrode gradually falls below the reaction consumption rate, leading to a decrease in the discharge voltage plateau and limiting energy output efficiency. Therefore, to ensure the normal operation of lithium-air batteries, excess air is typically introduced into the positive electrode side (3) to participate in the battery reaction. While this method is safe and feasible, using excessive air on the positive electrode side (3) results in significant air waste. To further improve the utilization rate of lithium-air batteries, an air circulation pump is generally installed between the air outlet and the air inlet of the lithium-air battery to ensure efficient air utilization.

[0039] The air circulation pumps in related technologies are generally electric circulation pumps. These pumps maintain the intake and exhaust of air by rotating an electric motor. This type of pump results in huge energy consumption, reduces the power generation efficiency of the power generation system, occupies the volume space of the lithium-air battery, and causes a lot of noise, which affects the further development of lithium-air batteries.

[0040] The following is combined with Figures 1 to 4 This describes an embodiment of the present application.

[0041] Reference Figure 1 As shown, according to an embodiment of this application, in one aspect, a lithium-air battery gas circulation pump is provided, suitable for lithium-air batteries, including a pump body, an inlet channel 6 formed on the pump body, an outlet channel 14, an inlet element disposed in the inlet channel 6, an outlet element disposed in the outlet channel 14, and a gas storage chamber 10 formed in the pump body. The pump body is configured to deform under the action of an electric current to change the volume of the gas storage chamber 10; the inlet channel 6 is connected to the gas storage chamber 10 and is used to draw in gas; the outlet channel 14 is connected to the gas storage chamber 10 and is used to discharge gas; the inlet element is configured to control the inlet airflow when the volume of the gas storage chamber 10 changes; the outlet element is configured to control the outlet airflow when the volume of the gas storage chamber 10 changes.

[0042] The aforementioned lithium-air battery gas circulation pump drives the volume change of the gas storage chamber 10 by directly deforming the pump body under the action of current, replacing the electric motor and transmission mechanism, which significantly reduces energy consumption and operating noise. At the same time, the integrated design reduces additional components and compresses the volume, solving the problems of high energy consumption, large size and high noise of electric circulation pumps in related technologies, and realizing efficient, energy-saving, compact and quiet gas circulation.

[0043] Specifically, in some embodiments of this application, the pump body includes an inlet support frame 8 and an outlet support frame 12, both of which are gradually expanding structures to optimize airflow distribution.

[0044] The intake support frame 8 forms the intake channel 6, and the exhaust support frame 12 forms the exhaust channel 14. A first piezoelectric film 9 and a second piezoelectric film 11 connect the larger opening end of the intake support frame 8 to the larger opening end of the exhaust support frame 12 to form an air storage cavity 10. The first piezoelectric film 9 and the second piezoelectric film 11 are connected to a circuit to undergo mechanical deformation under the action of alternating current, thereby changing the volume of the air storage cavity 10.

[0045] It should be noted that, in the above embodiments, the materials used to construct the inlet support frame 8 and the outlet support frame 12 should be metallic or non-metallic materials with a certain mechanical strength. The gradually expanding structure of the inlet support frame 8 and the outlet support frame 12 optimizes the airflow distribution, reduces turbulence and pressure loss, and improves gas circulation efficiency; the first and second piezoelectric films 11 connect the frame to form the gas storage cavity 10, and the volume change is controlled by precise mechanical deformation, further reducing energy loss and noise generation, and enhancing the stability and response speed of the system.

[0046] Optionally, in some embodiments of this application, the materials of the first piezoelectric film 9 and the second piezoelectric film 11 include polyvinylidene fluoride (PVDF) or other organic piezoelectric (film) materials, which have high piezoelectric constants and excellent mechanical toughness, ensuring efficient and reliable deformation, reducing energy conversion loss, and at the same time, the material damping characteristics reduce noise.

[0047] As a variation, the material of the piezoelectric thin film 9 can also be a piezoelectric crystal or a piezoelectric ceramic, such as lead zirconate titanate (PZT), to adapt to the temperature resistance or sensitivity requirements under different operating conditions.

[0048] In these embodiments, materials such as polyvinylidene fluoride, piezoelectric crystals, or piezoelectric ceramics have high voltage constants and excellent mechanical toughness, ensuring that the piezoelectric film 9 can efficiently and reliably deform under the action of high-frequency alternating current, reducing energy conversion losses. At the same time, the damping characteristics of the material itself reduce operating noise and extend the service life of the circulating pump, which is conducive to overall energy efficiency improvement and quiet operation.

[0049] Optionally, in some embodiments of this application, the intake element includes a first one-way valve 7 disposed in the intake channel 6 and configured to allow gas to flow in when the volume of the gas storage chamber 10 expands. More specifically, the first one-way valve 7 can be connected to the intake support frame 8. The first one-way valve 7, disposed in the intake channel 6, automatically opens using the negative pressure generated by the expansion of the gas storage chamber 10, allowing gas to flow in one direction, preventing backflow, simplifying the control logic, and reducing energy waste. This passive control mechanism improves the reliability of directional gas circulation and reduces system complexity and maintenance requirements.

[0050] Accordingly, in some embodiments of this application, the gas outlet element includes a second one-way valve 13, disposed in the gas outlet channel 14, configured to allow gas to flow out when the volume of the gas storage chamber 10 decreases. More specifically, the second one-way valve 13 can also be connected to the gas outlet support frame 12. Similarly, the second one-way valve 13, disposed in the gas outlet channel 14, automatically opens based on the positive pressure generated by the volume reduction of the gas storage chamber 10, ensuring one-way gas discharge and avoiding gas stagnation and mixing losses. Furthermore, the second one-way valve 13 can also work in conjunction with the first one-way valve 7 to achieve efficient passive airflow control, improve circulation efficiency, and reduce the energy consumption of active control components.

[0051] It should be noted that in the above embodiments, the first check valve 7 and the second check valve 13 are control components, and can be CV type, CH type, CO type, COA type or CL type check valves; As a modified implementation, the intake element may further include a third piezoelectric film disposed in the intake channel 6, configured to allow gas to flow in through mechanical deformation when the volume of the gas storage chamber 10 expands. As an active control element, the third piezoelectric film precisely adjusts its deformation via an electric field to open or close the intake channel 6, providing more refined airflow modulation capabilities and reducing frictional wear and noise from mechanical valves. Simultaneously, the fast piezoelectric response of the third piezoelectric film facilitates a more suitable gas supply, further reducing energy consumption and operating noise.

[0052] Similarly, as a modified implementation, the outlet element may also include a fourth piezoelectric film disposed in the outlet channel 14, configured to allow gas to flow out through mechanical deformation when the volume of the gas storage chamber 10 decreases. The fourth piezoelectric film controls the outlet channel 14 through deformation, achieving fully piezoelectric-driven airflow management and eliminating the sealing problems and lifespan limitations of mechanical valves. Furthermore, it can work in conjunction with the third piezoelectric film to ensure high precision and consistency of gas circulation, reduce energy leakage and noise, and improve the overall system efficiency and reliability.

[0053] It should be noted that the constituent materials of the third and fourth piezoelectric films are similar to those of the first piezoelectric film 9 and the second piezoelectric film 11. They can also be polyvinylidene fluoride (PVDF) (film) or other organic piezoelectric (film) materials, as well as piezoelectric crystals or piezoelectric ceramics, etc.

[0054] Based on the above embodiments, the lithium-air battery gas circulation pump further includes a control circuit connected to the inlet element, the outlet element, the first piezoelectric film 9, and the second piezoelectric film 11. The control circuit is configured to adjust the voltage or frequency of the alternating current applied to the first piezoelectric film 9 and the second piezoelectric film 11 according to the battery's state of charge or charging / discharging stage, so that the volume change of the gas storage chamber 10 matches the gas demand.

[0055] By monitoring the battery status in real time through the control circuit, the AC voltage or frequency applied to the piezoelectric film 9 is dynamically adjusted so that the volume change of the gas storage chamber 10 precisely matches the gas demand, avoiding energy waste caused by excessive or insufficient gas supply, optimizing the reaction efficiency of the lithium-air battery, and significantly improving the system's energy efficiency and adaptability.

[0056] Based on this, in some embodiments of this application, the control circuit is configured to: increase the AC voltage when the battery is discharging to increase the deformation amplitude of the piezoelectric element, thereby increasing the gas supply rate; and decrease the AC voltage when the battery is charging to decrease the deformation amplitude of the piezoelectric element, thereby reducing the gas supply. Through intelligent adjustment based on the battery charging and discharging stages, sufficient oxygen is provided to maintain battery power output during high demand periods, while gas supply is reduced during low demand periods to save energy. This dynamic optimization not only reduces overall energy consumption but also extends battery cycle life and enhances the stability and economy of the system under different operating conditions.

[0057] Optionally, in some embodiments of this application, to enhance control accuracy, the control circuit may also integrate a pressure sensor for real-time monitoring of the air pressure within the air storage chamber 10 and for feedback adjustment of the AC parameters. The control circuit may be integrated inside the pump body or coupled via an external connector to adapt to different installation requirements.

[0058] Reference Figure 2 As shown in the embodiments of this application, in another aspect, a power generation system is also provided, including an air supply unit 4 for a lithium-air battery gas circulation pump and a lithium-air battery, as described in any of the foregoing embodiments. The air supply unit 4 is connected to the air intake channel 6 of the lithium-air battery gas circulation pump to supply fresh air to the lithium-air battery gas circulation pump; the lithium-air battery is connected to the air supply unit 4 to receive the air supplied by the air supply unit 4 and / or to discharge incompletely reacted air to the air supply unit 4.

[0059] The aforementioned power generation system, through system-level integration, coordinates the high-efficiency lithium-air battery gas circulation pump with the air supply unit 4 and the lithium-air battery to achieve closed-loop gas management. The air supply unit 4 directly supplies fresh air to the lithium-air battery gas circulation pump, ensuring a stable oxygen supply. The lithium-air battery, connected to the air supply unit 4, enables the recovery and reuse of unreacted air, reducing fresh air requirements and peripheral size, thus significantly lowering the overall system's energy consumption and space occupation. Simultaneously, the piezoelectrically driven lithium-air battery gas circulation pump replaces the traditional electric motor, eliminating mechanical noise at its source, resulting in quiet and stable system operation. This comprehensively solves the problems of high energy consumption, large size, and high noise in related technologies, improving the efficiency and practicality of lithium-air batteries.

[0060] Specifically, the lithium-air battery includes a positive electrode 3, a negative electrode 1, and an exchange membrane 2. The positive electrode 3 is connected to the lithium-air battery gas circulation pump and air supply unit 4 for the oxygen reduction reaction; the negative electrode 1 is ion-conducting with the positive electrode 3 through the exchange membrane 2 for the lithium oxidation reaction; the exchange membrane 2 is disposed between the positive electrode 3 and the negative electrode 1 for lithium ion conduction.

[0061] It should be noted that the negative electrode 1 and positive electrode 3, including the negative electrode 1 and positive electrode 3 of a single cell and the negative electrode 1 and positive electrode 3 of a fuel cell stack, should be porous and conductive materials, specifically including non-metallic materials such as metal-based or carbon-based materials, and simultaneously supported with uniformly dispersed catalysts with catalytic activity, specifically including catalysts with air catalytic activity such as platinum and palladium; the exchange membrane 2 should be a membrane with ion transfer function, specifically including cation exchange membrane 2, anion exchange membrane 2, or neutral exchange membrane 2.

[0062] In the above scheme, the oxygen supply path is optimized by directly connecting the positive electrode 3 to the lithium-air battery gas circulation pump and air supply unit 4, which makes the oxygen reduction reaction fast and complete and improves the output efficiency of the battery. The negative electrode 1 is connected to the positive electrode 3 through the exchange membrane 2, which realizes the smooth transmission of lithium ions and avoids energy loss and heat accumulation. This structural design enhances the matching degree between the battery and the gas circulation system, makes the recovery of unreacted air more accurate, further reduces energy consumption and exhaust emissions, and the compact battery layout reduces the system volume, which is conducive to the miniaturization, high efficiency and low noise operation of the system.

[0063] As a variation, the air supply unit 4 may include multiple air sources (such as compressed air tanks and ambient air inlets) and select the air supply mode via a switching valve to adapt to different load requirements. The lithium-air battery layout can be stacked or modular for easy capacity expansion. The system may also include temperature and humidity sensors to monitor environmental conditions and adjust gas circulation parameters to enhance adaptability.

[0064] In conjunction with the above embodiments, refer to Figure 3 As shown, the operation steps of the lithium-air battery system combined with the piezoelectric air circulation pump 5 of this application are as follows: Air is discharged from the air supply unit 4 and enters the positive electrode 3 side of the lithium-air battery. There, a redox reaction occurs in the electrode, causing it to lose electrons and transform into oxygen ions. Simultaneously, lithium ions generated on the negative electrode 1 move through the exchange membrane 2 towards the positive electrode 3 side. The lost electrons move through the external circuit towards the positive electrode 3 side. Oxygen from the ambient air passes through the oxygen diffusion layer of the positive electrode 3 and enters the positive electrode 3 side, undergoing a reduction reaction and gaining electrons. Unreacted air on the positive electrode 3 side is discharged from the positive electrode 3 and, powered by the air circulation pump, enters the air circulation pump, which then discharges it into the air supply pipeline. There, it enters the positive electrode 3 side along with the air generated by the air supply unit 4 to react again. This cycle maintains the efficient and stable operation of the lithium-air battery.

[0065] Battery state-based feedback regulation: Lithium-air batteries continuously consume oxygen during discharge. The remaining battery capacity can be monitored in real-time by tracking voltage changes in piezoelectric elements, and the compressor's air intake can be dynamically adjusted. When the battery charge decreases, the voltage is increased to amplify the change in the piezoelectric film, thereby increasing the oxygen supply rate to maintain output power. Furthermore, different short-term strategies are employed based on the battery's charging and discharging phases. During the charging phase (oxygen release), air intake is reduced, while during the discharging phase (oxygen consumption), air intake is increased to match the battery's reaction requirements and prevent excessive or insufficient oxygen.

[0066] According to an embodiment of this application, a method for controlling a lithium-air battery gas circulation pump is also provided, comprising: applying alternating current to a piezoelectric element (such as a first piezoelectric film 9 and a second piezoelectric film 11) of the lithium-air battery gas circulation pump to cause mechanical deformation of the piezoelectric element, thereby changing the volume of the gas storage chamber 10; controlling the gas to be drawn in from the inlet channel 6 and discharged from the outlet channel 14 by the volume change of the gas storage chamber 10 to achieve directional circulation of the gas; wherein, the voltage or frequency of the alternating current is dynamically adjusted according to the charging and discharging state of the battery to match the gas demand.

[0067] The above control method directly drives gas circulation through the deformation of piezoelectric elements, avoiding mechanical transmission losses and reducing energy consumption; dynamically adjusting AC parameters ensures precise matching between gas supply and battery demand, improving system response speed and efficiency.

[0068] Specifically, during the battery discharge phase, increasing the AC voltage increases the deformation amplitude of the piezoelectric element and improves the gas supply rate to maintain high power output of the battery; during the battery charging phase, decreasing the AC voltage reduces the deformation amplitude and decreases the gas supply to save energy.

[0069] In some alternative embodiments, the control method may also include detecting battery voltage and current signals and optimizing the adjustment logic using a PID algorithm to enhance stability.

[0070] As a variation, the control method can be implemented via software and embedded in a microcontroller, allowing users to customize the gas supply curve to adapt to different battery types or environmental conditions. The method may also include a calibration step: performing a baseline test upon system startup to set initial parameters and ensure operational accuracy.

[0071] Reference Figure 4 As shown, combined with this control method, the working process of the lithium-air battery gas circulation pump of this application is as follows: Step S1-1: No power state: When no current passes through, the first piezoelectric film 9 and the second piezoelectric film 11 are in a parallel state, no gas passes through the air inlet channel 6 and the air outlet channel 14, and the lithium air battery gas circulation pump is in a stable non-operating state. Step S1-2: Air intake state: After the introduction of AC power, the first piezoelectric film 9 and the second piezoelectric film 11 undergo mechanical deformation under the action of the electric field, and both gradually expand outward, further increasing the volume of the air storage cavity 10 and reducing the air pressure. The pressure difference between the air storage cavity 10 and the atmosphere causes air to enter the air storage cavity 10 from the air intake channel 6 through the first one-way valve 7 to maintain pressure balance and complete the air intake state. Step S1-3: Gas discharge state: When the alternating current changes, the first piezoelectric film 9 and the second piezoelectric film 11 undergo mechanical deformation under the action of the electric field, and both gradually shrink inward, which further reduces the volume of the gas storage cavity 10 and increases the gas pressure. The pressure difference between the gas storage cavity 10 and the atmosphere causes air to enter the gas discharge channel 14 from the gas storage cavity 10 through the second one-way valve 13 to maintain pressure balance and complete the gas discharge state. As described in steps S1-2 and S1-3, the high-frequency change of the alternating current enables the device to achieve high-frequency air intake and exhaust, while the one-way valve enables the piezoelectric air circulation pump 5 to directionally draw in and output air at high frequency, further maintaining the stable operation of the piezoelectric air circulation pump 5.

[0072] Stable air intake and exhaust are achieved through the movement of piezoelectric diaphragms on both sides of the air circulation pump, while directional air output is controlled by one-way valves or piezoelectric diaphragms on both sides of the pump. Compared to traditional electric air circulation pumps, this device is smaller and has a simpler structure. During operation, it controls the piezoelectric diaphragm movement solely through changes in current, resulting in low noise and lower energy consumption. Therefore, this device boasts significant advantages such as simple structure, high efficiency and energy saving, quiet and stable operation, and small size.

[0073] Although embodiments of this application have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of this application, and all such modifications and variations fall within the scope defined by the appended claims.

Claims

1. A lithium-air battery gas circulation pump, characterized in that, include: A pump body for forming an air storage chamber, the pump body being configured to deform under the action of an electric current to change the volume of the air storage chamber; An air intake channel is formed on the pump body and communicates with the air storage chamber for drawing in gas; An exhaust channel is formed on the pump body and communicates with the gas storage chamber for discharging gas. An intake element is disposed within the intake channel and configured to control the intake airflow when the volume of the air storage chamber changes; An air outlet element is disposed within the air outlet channel and configured to control the air outlet flow when the volume of the air storage chamber changes.

2. The lithium-air battery gas circulation pump according to claim 1, characterized in that, The pump body includes: An intake support frame is used to form the intake channel, and the intake support frame has a gradually expanding structure; An exhaust support frame is used to form the exhaust channel, and the exhaust support frame has a gradually expanding structure. A first piezoelectric film and a second piezoelectric film are connected to the larger opening end of the air inlet support frame and the larger opening end of the air outlet support frame to form the air storage cavity.

3. The lithium-air battery gas circulation pump according to claim 2, characterized in that, The materials of the first and second piezoelectric films include polyvinylidene fluoride, piezoelectric crystals, or piezoelectric ceramics.

4. The lithium-air battery gas circulation pump according to claim 1, characterized in that, The intake element includes: A first one-way valve is disposed in the air intake channel and configured to allow gas to flow in when the volume of the gas storage chamber expands.

5. The lithium-air battery gas circulation pump according to claim 1, characterized in that, The air outlet element includes: A second one-way valve is disposed in the gas outlet channel and configured to allow gas to flow out when the volume of the gas storage chamber decreases.

6. The lithium-air battery gas circulation pump according to claim 1, characterized in that, The intake element includes: A third piezoelectric film is disposed in the air inlet channel and configured to allow gas to flow in when the volume of the gas storage chamber expands.

7. The lithium-air battery gas circulation pump according to claim 1, characterized in that, The air outlet element includes: A fourth piezoelectric film is disposed in the gas outlet channel and configured to allow gas to flow out when the volume of the gas storage chamber decreases.

8. The lithium-air battery gas circulation pump according to any one of claims 2 to 7, characterized in that, The lithium-air battery gas circulation pump also includes: A control circuit, connected to the air inlet element, the air outlet element, the first piezoelectric film, and the second piezoelectric film, is configured to adjust the voltage or frequency of the alternating current applied to the first piezoelectric film and the second piezoelectric film according to the state of charge or charging / discharging stage of the battery, so that the volume change of the gas storage chamber matches the gas demand.

9. The lithium-air battery gas circulation pump according to claim 8, characterized in that, The control circuit is configured as follows: When the battery is in a discharging state, increasing the AC voltage increases the deformation amplitude of the piezoelectric element, thereby increasing the gas supply rate. When the battery is charging, reducing the AC voltage reduces the deformation of the piezoelectric element, thereby reducing the gas supply.

10. A power generation system, characterized in that, include: The lithium-air battery gas circulation pump according to any one of claims 1 to 9; An air supply unit is connected to the air intake channel of the lithium-air battery gas circulation pump to supply air to the lithium-air battery gas circulation pump; A lithium-air battery is connected to the air supply unit to receive air supplied by the air supply unit and / or discharge incompletely reacted air to the air supply unit.

11. The lithium-air battery gas circulation pump according to claim 8, characterized in that, The lithium-air battery includes a positive electrode, a negative electrode, and an exchange membrane; The positive electrode is connected to the lithium-air battery gas circulation pump and the air supply unit for oxidation-reduction reaction; The negative electrode is connected to the positive electrode through the exchange membrane to conduct lithium oxidation reaction.

12. A control method for a lithium-air battery gas circulation pump, characterized in that, include: An alternating current is applied to the piezoelectric element on the pump body of the lithium-air battery gas circulation pump, causing the pump body to deform and changing the volume of the gas storage chamber: When the battery is in a discharging state, increasing the AC voltage increases the deformation amplitude of the piezoelectric element, thereby increasing the gas supply rate. When the battery is charging, reducing the AC voltage reduces the deformation of the piezoelectric element, thereby reducing the gas supply.

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