Reversible solid oxide battery energy storage device and method based on fluidized bed electrode

Abstract

The invention discloses a reversible solid oxide battery energy storage device based on a fluidized bed electrode. The reversible solid oxide battery energy storage device comprises a reactor main body, a solid oxide battery, an energy storage tank, an energy release tank and a gas circulation outer loop, two sides of the reactor main body are respectively communicated with the energy storage tank and the energy release tank; the gas circulation outer path comprises a fan, and mixed gas of hydrogen and water vapor is blown into the reactor main body through the fan. When the device is used, in the energy storage stage, the solid oxide battery consumes electric power to electrolyze water vapor into hydrogen, the hydrogen reduces ferroferric oxide into iron elementary substances, and energy storage is achieved; in the energy release stage, the iron elementary substance reacts with water vapor to generate hydrogen, the solid oxide battery oxidizes the hydrogen to generate power, and energy release is achieved. According to the device, hydrogen and water vapor mixed gas serves as a fluidizing and energy medium, non-molten metal electrolysis energy storage is achieved, the energy storage density of the system is high, the bottleneck problem that hydrogen is difficult to store in traditional electrolysis water energy storage is solved, and the application prospect is wide.

Description

Technical Field

[0001] The present application relates to the field of reversible solid oxide batteries and fluidization technology, and in particular to a reversible solid oxide battery energy storage device and method based on fluidized bed electrodes. Background Art

[0002] The instability of renewable energy not only wastes energy but also significantly impacts the power grid. Existing lithium-ion batteries have an energy density of only 0.3-0.5 kWh / kg (lithium iron phosphate systems), while lead-acid batteries have an energy density of less than 0.1 kWh / kg. Reversible solid oxide batteries mostly use gas as fuel, and hydrogen storage through water electrolysis relies on large hydrogen storage systems, severely limiting the commercialization of energy storage technology. While some metals can serve as high-energy-density fuels, their reactivity limits their direct application in electrolysis energy storage systems.

[0003] Fluidization technology propels solid particles through a fluidizing medium, imparting fluid properties. This technology leverages the high thermal conductivity of solids and the fluidity of fluids to achieve efficient heat and mass transfer, as well as excellent chemical reaction rates. Currently, fluidization technology has been widely applied in various fields, including thermochemistry, electrochemistry, and energy.

[0004] In the field of fluidized bed electrodes, patent CN113178605B provides a fluidized bed anode solid oxide fuel cell, which includes an anode compartment, a cathode compartment, anode particles, a cathode layer, an anode current collecting layer, a cathode current collecting layer, and an electrolyte layer. The exposed surface of the bed particles increases the electrode reaction interface, and fluidization causes the anode particles to continuously agitate, increasing the heat and mass transfer rates within the electrode and making the electrode temperature more uniform. The collision of particles also improves the electrode's resistance to carbon deposition. However, the bed material only plays a catalytic role and does not directly participate in the electrochemical reaction itself, making it impossible to achieve metal energy storage.

[0005] In terms of metal electrochemical energy storage, patent CN111810269B proposes a polygeneration power generation system based on metal fuel aluminum energy storage and its operating method. The system uses alumina as a raw material, melts the alumina under high temperature conditions, and then undergoes an electrolytic reaction to produce metallic aluminum. The metallic aluminum then reacts with water in an alkaline solution reactor to produce hydrogen, which is stored in a hydrogen storage tank to achieve energy storage. This patent uses aluminum as an energy transmission medium, which has the advantage of high energy density. However, the electrolysis of alumina must be carried out in a high-temperature molten state, which consumes a lot of energy. In addition, the system uses hydrogen as the energy storage medium, which requires additional hydrogen storage tanks, and the system cannot directly achieve power regeneration.

[0006] The theoretical energy storage density of the iron-water hydrogen production reaction is 1.88 kWh / kg. In combination with the reaction system of the solid oxide cell, the energy storage density of the system is still as high as 0.90 kWh / kg, far higher than that of the lithium ion battery system, considering the power generation efficiency of 60% and the electrolysis efficiency of 80% of the battery. Therefore, it is urgent to develop a solid oxide cell energy storage device which can not only avoid high-energy consumption metal oxide electrolysis technology, but also solve the bottleneck problem of low energy density or serious dependence on large-scale hydrogen storage of traditional energy storage technology. SUMMARY

[0007] Object: In order to overcome the deficiencies in the prior art, the present application provides a reversible solid oxide cell energy storage device and method based on fluidized bed electrode, which uses solid oxide cell to realize high-density metal energy storage, avoids high-energy consumption molten metal oxide electrolysis reaction and complex hydrogen storage system, and improves the energy storage density of the system.

[0008] To solve the above technical problems, the technical scheme adopted by the present application is:

[0009] In a first aspect, the present application provides a reversible solid oxide cell energy storage device based on fluidized bed electrode, characterized in that it comprises: a reactor main body, a solid oxide cell, an energy storage tank, an energy release tank and a gas circulation external loop. The middle part of the reactor main body is connected with the solid oxide cell, one side is connected with the energy storage tank through the energy storage tank feeding screw, and the other side is connected with the energy release tank through the energy release tank feeding screw. The gas circulation external loop further comprises a fan, and the bottom of the reactor main body is provided with a air distribution plate. The gas is blown into the reactor main body through the fan and the air distribution plate. The lower part of the side of the reactor main body close to the energy storage tank is provided with an energy storage tank overflow port, which is connected to the energy storage tank through an energy storage tank overflow pipeline. The upper part of the side of the reactor main body close to the energy release tank is provided with an energy release tank overflow port, which is connected to the energy release tank through an energy release tank overflow pipeline.

[0010] The reversible solid oxide cell energy storage device based on fluidized bed electrode combines the fluidized bed electrode with the reversible solid oxide cell, realizes the reversible conversion of energy storage and energy release, and has high energy utilization efficiency. The design of the energy storage tank and the energy release tank overflow port utilizes the density difference for automatic sorting, and optimizes the material distribution.

[0011] In some embodiments, the solid oxide cell is of a tubular structure, the fuel electrode is located on the outside, and the oxygen electrode is located on the inside. The electrolyte of the solid oxide cell is an oxygen ion conductor ceramic.

[0012] In some embodiments, the reactor body is filled with metal energy storage particles; the metal energy storage particles are iron composite oxides selected from one or more of the following: metal iron particles, iron aluminum compounds, iron zirconium compounds, iron oxides, and aluminum oxides. Fluidization of the metal energy storage particles enhances the redox reaction of the metal particles, improving the system response rate.

[0013] In some embodiments, the energy storage tank overflow pipeline is provided with an energy storage tank overflow valve, and the energy release tank overflow pipeline is provided with an energy release tank overflow valve.

[0014] In some embodiments, the gas circulation external loop further comprises a gas buffer tank installed between the reactor body and the fan.

[0015] In some embodiments, the gas in the gas circulation external loop is a mixture of hydrogen and water vapor.

[0016] In some embodiments, the gas circulation external loop further comprises a heat preservation heating device to prevent water vapor condensation.

[0017] In a second aspect, the present application provides a method for using the reversible solid oxide cell energy storage device based on a fluidized bed electrode according to the first aspect, comprising: In the energy release stage, the reactor body and the energy storage tank are filled with reduced metal energy storage particles, the energy storage tank feeding screw, the energy release tank feeding screw, the energy storage tank overflow valve and the energy release tank overflow valve are closed, the reactor body is heated, and the solid oxide cell is controlled in a constant current discharge state; the fan is started, the energy storage tank feeding screw is opened, the reduced metal energy storage particles in the energy storage tank are sent into the reactor body, and the energy release tank overflow valve is opened to collect the oxidized metal energy storage particles into the energy release tank.

[0018] Hydrogen is used as the gas in the outer loop of the gas circulation. The energy storage tank feeding screw feeds the reduced metal energy storage particles in the energy storage tank into the reactor body. In the reactor body, the mixture of hydrogen and water vapor drives the metal energy storage particles to form fluidization. The water vapor and the iron elements in the metal energy storage particles react to produce hydrogen. The hydrogen reaches the surface of the solid oxide battery fuel electrode and undergoes an electrochemical reaction to generate water vapor and release electrical energy. The water vapor further oxidizes the iron elements in the metal energy storage particles. The iron oxidation reaction is achieved using hydrogen and water vapor as the medium. The oxidized metal energy storage particles show stratification in the fluidized bed due to the reduced density. , through the overflow valve of the energy release tank at the top, it is collected in the energy release tank for use in the subsequent energy storage stage; wherein, the fluidization number of the metal energy storage particles is controlled by adjusting the fan flow to form bubbling fluidization, and the bubbling fluidization promotes the interaction and mass transfer process between the metal energy storage particles and water vapor, thereby increasing the oxygen partial pressure on the surface of the metal energy storage particles, strengthening the thermochemical oxidation reaction, and promoting the rapid generation of hydrogen to provide fuel for the solid oxide battery. At the same time, bubbling fluidization can separate the oxidized energy storage particles; air is introduced into the oxygen electrode of the solid oxide battery to maintain the supply of oxygen ions and achieve stable output of electricity.

[0019] In the energy storage stage, after the device completes energy release, close the energy release tank overflow valve and the energy storage tank feeding screw, open the energy release tank feeding screw to send the oxidized metal energy storage particles in the energy release tank into the reactor body, open the energy storage tank overflow valve to collect the reduced metal energy storage particles into the energy storage tank; and apply voltage to the solid oxide battery through a DC power supply.

[0020] The energy release tank feeding screw feeds the oxidized metal energy storage particles in the energy release tank into the reactor body. In the reactor body, the mixture of hydrogen and water vapor drives the metal energy storage particles to form fluidization. The hydrogen and the iron oxides in the metal energy storage particles undergo a reduction reaction to generate water vapor. The water vapor reaches the surface of the solid oxide battery fuel electrode and undergoes an electrochemical reaction to generate hydrogen and consume electrical energy. The hydrogen further reduces the iron oxides in the metal energy storage particles. The reduction reaction of the iron oxides is achieved using hydrogen and water vapor as the medium. The reduced metal energy storage particles have increased density. , stratification occurs in the fluidized bed, and the gas is collected into the energy storage tank through the overflow valve at the bottom of the energy storage tank for use in the subsequent energy release stage; wherein, the fluidization number of the metal energy storage particles is controlled by adjusting the fan flow to form bubbling fluidization, and the bubbling fluidization promotes the interaction and mass transfer process between the metal energy storage particles and hydrogen, thereby reducing the oxygen partial pressure on the surface of the metal energy storage particles, strengthening the thermochemical reduction reaction, and promoting the rapid generation of water vapor to provide raw gas for the solid oxide battery; pure oxygen is generated in the oxygen electrode of the solid oxide battery to realize the multi-generation of the device.

[0021] In some embodiments, the reactor body is heated to 700-850° C. during the energy release stage; In the energy release stage, the solid oxide battery is controlled to be in a constant current discharge state in a voltage range of 0.7-1 V. In the energy storage stage, the voltage applied to the solid oxide battery by a DC power supply is in a voltage range of 1.3-2.5 V.

[0022] In some embodiments, after the fan is started, its flow rate is adjusted to control the fluidization number of the metal energy storage particles. When the fluidization number is controlled within the range of 3-10, the metal energy storage particles form a bubbling fluidized state. The diameter of the metal energy storage particles in the bubbling fluidized state is between 300-800 μm in narrow sieving.

[0023] Beneficial effects: The reversible solid oxide battery energy storage device based on fluidized bed electrodes provided by the present invention avoids the high-energy consumption molten metal oxide electrolysis reaction. The system uses hydrogen and water vapor as media to connect the redox reaction of the metal and the electrochemical reaction of the solid oxide battery, thereby improving the electrochemical energy storage efficiency; energy is directly stored in the metal particles, avoiding the complex hydrogen storage system and improving the energy storage density of the system; the redox reaction of the metal particles is enhanced by the fluidization of the metal energy storage particles, thereby improving the system response rate, and has broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 Schematic diagram of the structure of a reversible solid oxide battery energy storage device based on fluidized bed electrodes in an embodiment of the present invention.

[0025] In the figure: 1. Solid oxide battery; 2. Gas circulation external loop; 3. Gas buffer tank; 4. Fan; 5. Reactor body; 6. Energy storage tank feeding screw; 7. Energy storage tank; 8. Energy storage tank overflow port; 9. Energy storage tank overflow port valve; 10. Air distribution plate; 11. Energy release tank feeding screw; 12. Energy release tank; 13. Energy release tank overflow port, 14; Energy release tank overflow port valve. DETAILED DESCRIPTION

[0026] The following will be combined with the accompanying drawings to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention, its application, or use.

[0027] Unless otherwise specifically stated, the relative arrangement of the parts and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present invention. At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the drawings are not drawn according to actual proportional relationships. The techniques, methods and equipment known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, the techniques, methods and equipment should be considered as part of the authorization specification. In all examples shown and discussed here, any specific values ​​should be interpreted as being merely exemplary, not as limitations. Therefore, other examples of the exemplary embodiments may also include different values. It should be noted that similar numbers and letters represent similar items in the following figures, and therefore, once an item is defined in one figure, it does not need to be further discussed in subsequent figures.

[0028] The present invention will be further described below with reference to the examples.

[0029] Example 1:

[0030] like Figure 1 As shown, the present invention provides a reversible solid oxide battery energy storage device based on fluidized bed electrodes, including a solid oxide battery 1, a gas circulation outer loop 2, a gas buffer tank 3, a fan 4, a reactor body 5, an energy storage tank feeding screw 6, an energy storage tank 7, an energy storage tank overflow port 8, an energy storage tank overflow port valve 9, an air distribution plate 10, an energy release tank feeding screw 11, an energy release tank 12, an energy release tank overflow port 13, and an energy release tank overflow port valve 14.

[0031] The reactor body 5 is connected to the solid oxide cell 1 in the middle, with one side connected to the energy storage tank 7 via the energy storage tank feed screw 6 and the other side connected to the energy release tank 12 via the energy release tank feed screw 11. An air distribution plate 10 is located at the bottom of the reactor body 5. Gas passes through the fan 4 and is blown into the reactor body 5 through the air distribution plate 10. The gas circulation outer loop 2 also includes a gas buffer tank 3 installed between the reactor body 5 and the fan 4.

[0032] An energy storage tank overflow port 8 is provided at the lower part of the reactor body 5 close to the energy storage tank 7, and is connected to the energy storage tank 7 through an energy storage tank overflow pipe; an energy release tank overflow port 13 is provided at the upper part of the reactor body 5 close to the energy release tank 12, and is connected to the energy release tank 12 through an energy release tank overflow pipe; an energy storage tank overflow port valve 9 is provided on the energy storage tank overflow pipe, and an energy release tank overflow port valve 14 is provided on the energy release tank overflow pipe.

[0033] In this embodiment, the electrolyte of the solid oxide battery 1 is oxygen ion conductor ceramic.

[0034] In this embodiment, the solid oxide cell 1 is a tubular structure, with the fuel electrode located on the outside and the oxygen electrode located on the inside.

[0035] In this embodiment, the gas in the gas circulation outer loop 2 is a mixture of hydrogen and water vapor, and the gas circulation outer loop 2 further includes a heat preservation and heating device for preventing condensation of water vapor.

[0036] The reactor body 5 is filled with metal energy storage particles. The metal energy storage particles are iron composite oxides, selected from one or more of metallic iron particles, iron-aluminum compounds, iron-zirconium compounds, and core-shell particles composed of iron oxide and aluminum oxide. In this embodiment, the metal energy storage particles are 80 wt% Fe and 20 wt% Al2O3, with a particle diameter between 300-500 μm on a narrow sieve.

[0037] Example 2:

[0038] This embodiment, based on the first embodiment, provides a method for using a reversible solid oxide battery energy storage device based on a fluidized bed electrode, including: Energy release stage: Reduced metal energy storage particles are placed in the energy storage tank 7 and the reactor body 5. The filling volume of the energy storage tank 7 is 1 L, the capacity of the reactor body 5 is 200 mL, and the filling height of the metal energy storage particles is 1 / 3 of the height of the energy storage tank 7; the solid oxide battery 1 uses yttria-stabilized zirconia (YSZ) ceramic as the electrolyte, a composite material composed of nickel (Ni) and YSZ as the fuel electrode, cerium oxide-stabilized gadolinium oxide (GDC) as the cathode isolation layer, and lanthanum strontium cobalt iron perovskite as the oxygen electrode; the solid oxide battery 1 uses an electrolyte support structure, the fuel electrode is outside the tube, and the oxygen electrode is inside the tube.

[0039] Close the energy storage tank feeding screw 6, the energy release tank feeding screw 11, the energy storage tank overflow valve 9 and the energy release tank overflow valve 14, and use hydrogen as the starting gas for the gas circulation outer loop 1; start the fan 4, set the fluidization number to 3, and set the discharge current of the solid oxide battery 1 to 0 A; heat the reactor body 5 to 750°C under a hydrogen atmosphere, and after reduction, control the solid oxide battery 1 to a constant voltage discharge state through an electrochemical workstation; introduce air into the oxygen electrode of the solid oxide battery 1, and control the discharge voltage of the single battery to 0.85 V.

[0040] Set the fluidization number to 5 to form bubbling fluidization, fluidize the metal energy storage particles in the reactor body 5, open the energy storage tank feeding screw 6 to feed the reduced metal energy storage particles in the energy storage tank 7 into the reactor body 5, open the energy release tank overflow valve 14, and collect the oxidized metal energy storage particles into the energy release tank 12. The capacity of the energy release tank 12 is designed to be 1.5 L.

[0041] The energy storage tank feeding screw feeds the reduced metal energy storage particles in the energy storage tank into the reactor body 5. The mixture of hydrogen and water vapor in the reactor body 5 drives the metal energy storage particles to form fluidization. The water vapor and the iron in the metal energy storage particles react to produce hydrogen. The hydrogen reaches the surface of the fuel electrode of the solid oxide battery 1 and undergoes an electrochemical reaction to generate water vapor and release electrical energy. The water vapor further oxidizes the iron element in the metal energy storage particles, and the iron oxidation reaction is realized using hydrogen and water vapor as media. The oxidized metal energy storage particles show stratification in the fluidized bed due to the decrease in density. They are collected in the energy release tank through the overflow valve of the energy release tank at the top for use in the subsequent energy storage stage. The metal energy storage particles in the energy release tank are calculated through density detection. The iron content in ferroferric oxide accounts for 94.6% of the total iron content.

[0042] Energy storage stage: After the device completes energy release, close the energy release tank overflow valve 14 and the energy storage tank feeding screw 6, open the energy release tank feeding screw 11 to feed the oxidized metal energy storage particles in the energy release tank 12 into the reactor body 5, open the energy storage tank overflow valve 9 to collect the reduced metal energy storage particles into the energy storage tank 7, stop the air supply to the oxygen electrode, and apply a voltage of 1.5 V to the solid oxide battery 1 through the electrochemical workstation.

[0043] The energy release tank feeding screw 11 feeds the oxidized metal energy storage particles in the energy release tank 12 into the reactor body 5. The mixture of hydrogen and water vapor in the reactor body 5 drives the metal energy storage particles to form fluidization. The hydrogen and the iron oxides in the metal energy storage particles undergo a reduction reaction to generate water vapor. The water vapor reaches the surface of the fuel electrode of the solid oxide cell 1 and undergoes an electrochemical reaction to generate hydrogen and consume electrical energy. The hydrogen further reduces the iron oxides in the metal energy storage particles, and the reduction reaction of the iron oxides is realized using hydrogen and water vapor as media. The reduced metal energy storage particles undergo stratification in the fluidized bed due to the increase in density, and are collected into the energy storage tank 7 through the overflow valve 9 at the bottom of the energy storage tank for use in the subsequent energy release stage.

[0044] The metal energy storage particles in the energy release tank 12 were calculated through density detection. The results showed that the iron content in the metal iron particles accounted for 93.4% of the total iron content. The electrolysis power consumption and fuel cell power generation were calculated. The results showed that the single-cycle energy storage density of this system was 0.92 kWh / kg, which was much higher than that of the lithium-ion battery system.

[0045] The above is only a preferred embodiment of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A reversible solid oxide battery energy storage device based on fluidized bed electrodes, characterized in that: include: Reactor body, solid oxide battery, energy storage tank, energy release tank and gas circulation outer loop; The middle part of the reactor body is connected to the solid oxide battery, one side is connected to the energy storage tank through the energy storage tank feeding screw, and the other side is connected to the energy release tank through the energy release tank feeding screw; The gas circulation outer circuit also includes a blower, and an air distribution plate is provided at the bottom of the reactor body. The gas passes through the blower and is blown into the reactor body through the air distribution plate. The gas in the gas circulation outer circuit is a mixture of hydrogen and water vapor. An energy storage tank overflow port is provided at the lower part of the reactor body close to the energy storage tank, and is connected to the energy storage tank through an energy storage tank overflow pipe; an energy release tank overflow port is provided at the upper part of the reactor body close to the energy release tank, and is connected to the energy release tank through an energy release tank overflow pipe.

2. The reversible solid oxide battery energy storage device based on fluidized bed electrodes according to claim 1, characterized in that: The solid oxide cell has a tubular structure, with the fuel electrode located on the outside and the oxygen electrode located on the inside; The electrolyte of the solid oxide battery is an oxygen ion conductor ceramic.

3. The reversible solid oxide battery energy storage device based on fluidized bed electrodes according to claim 2, characterized in that: The reactor body is filled with metal energy storage particles; the metal energy storage particles are composite oxides of iron, selected from one or more of metallic iron particles, iron-aluminum compounds, iron-zirconium compounds, core-shell particles composed of iron oxide and aluminum oxide.

4. The reversible solid oxide battery energy storage device based on fluidized bed electrodes according to claim 3, characterized in that: An energy storage tank overflow port valve is provided on the energy storage tank overflow pipe, and an energy release tank overflow port valve is provided on the energy release tank overflow pipe.

5. The reversible solid oxide battery energy storage device based on fluidized bed electrodes according to claim 4, characterized in that: The gas circulation outer loop also includes a gas buffer tank installed between the reactor body and the fan.

6. The reversible solid oxide battery energy storage device based on fluidized bed electrodes according to claim 5, characterized in that: The gas circulation outer loop also includes a heat preservation and heating device for preventing water vapor from condensing.

7. A method for using the reversible solid oxide battery energy storage device based on fluidized bed electrodes according to claim 6, characterized in that: include: In the energy release stage, the energy storage tank and the reactor body are filled with reduced metal energy storage particles, the energy storage tank feeding screw, the energy release tank feeding screw, the energy storage tank overflow valve and the energy release tank overflow valve are closed, the reactor body is heated, and the solid oxide battery is controlled in a constant current discharge state; the fan is started, the energy storage tank feeding screw is opened, and the reduced metal energy storage particles in the energy storage tank are fed into the reactor body, the energy release tank overflow valve is opened, and the oxidized metal energy storage particles are collected into the energy release tank; In the energy storage stage, after the device completes energy release, close the energy release tank overflow valve and the energy storage tank feeding screw, open the energy release tank feeding screw to send the oxidized metal energy storage particles in the energy release tank into the reactor body, open the energy storage tank overflow valve to collect the reduced metal energy storage particles into the energy storage tank; and apply voltage to the solid oxide battery through a DC power supply.

8. The method for using the reversible solid oxide battery energy storage device based on fluidized bed electrodes according to claim 7, characterized in that: In the energy release stage, the reactor body is heated to 700-850°C; In the energy release stage, the solid oxide battery is controlled to be in a constant current discharge state in a voltage range of 0.7-1 V. In the energy storage stage, the voltage applied to the solid oxide battery by a DC power supply is in a voltage range of 1.3-2.5 V.

9. The method for using the reversible solid oxide battery energy storage device based on fluidized bed electrodes according to claim 7, characterized in that: After the fan is started, its flow rate is adjusted to control the fluidization number of the metal energy storage particles. When the fluidization number is controlled within the range of 3-10, the metal energy storage particles form a bubbling fluidized state; the diameter of the metal energy storage particles in the bubbling fluidized state is between 300-800 μm in a narrow sieve.

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