High energy density-oriented and high power density-oriented fuel-assisted rechargeable battery and preparation method therefor

Abstract

The present invention provides a high energy density-oriented and high power density-oriented fuel-assisted rechargeable battery and a preparation method therefor, said preparation method comprising the following steps: assembling a gas diffusion electrode, a separator, and a metal film, then adding an electrolyte, and obtaining a full cell, the gas diffusion electrode being provided with a vertical gas diffusion channel and / or a three-dimensional disordered gas diffusion channel, which has a porosity of 0.1%-80%; and placing the full cell into a breathable casing, connecting a positive electrode and a negative electrode to an external circuit via wires, and obtaining a high energy density-oriented and high power density-oriented fuel-assisted rechargeable battery. Compared with the existing technology, according to the technical solution provided by the present invention, reaction between electrodes during charging is radically changed, the charging voltage is greatly reduced, and the overpotential of the battery is effectively reduced. According to the technical solution provided by the present invention, the loss of electrical energy of a metal-air battery when being charged under a large current density is remarkably reduced, the charging efficiency of the battery is greatly improved, and the service life of the battery is obviously prolonged.

Description

A fuel-assisted rechargeable battery with high energy density and high power density and its preparation method

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on January 26, 2024, with application number 202410115147.9 and invention name “A fuel-assisted rechargeable battery for high energy density and high power density and its preparation method”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present invention relates to the technical field of new energy batteries, and more specifically, to a fuel-assisted rechargeable battery with high energy density and high power density and a preparation method thereof. Background Art

[0003] With modern society's increasing emphasis on high-energy-density battery technology and clean energy, metal-air batteries have attracted widespread attention due to their high theoretical specific capacity, lower cost, and improved safety. However, challenges remain, such as large differences in charge and discharge platforms, low round-trip energy efficiency, and poor cycling reversibility.

[0004] Most existing solutions are based on optimizing electrodes and electrolytes, developing new catalysts, and designing new battery structures. However, these solutions can only have limited effects and will greatly increase the cost of battery manufacturing, which is not conducive to their application in actual production (Science 371, 46-51 (2021)).

[0005] Summary of the Invention

[0006] In view of this, in order to solve the problems of large overpotential, low round-trip energy efficiency and low power density of traditional metal-air batteries, the present invention provides a fuel-assisted rechargeable battery with high energy density and high power density and a preparation method thereof. The fuel-assisted rechargeable battery prepared by the preparation method provided by the present invention can greatly improve the charging power of the original battery, and when used in new energy vehicles, it can also avoid the challenges brought by portable hydrogen storage, providing a new solution for the fast charging technology of future new energy vehicles.

[0007] The present invention provides a method for preparing a fuel-assisted rechargeable battery with high energy density and high power density, comprising the following steps:

[0008] Assembling a gas diffusion electrode, a diaphragm, and a metal membrane and then adding an electrolyte to obtain a full battery; the gas diffusion electrode has vertical gas diffusion channels and / or three-dimensional disordered gas diffusion channels, and a porosity of 0.1% to 80%;

[0009] The above-mentioned full battery is placed in a ventilated shell, and the positive and negative electrodes are connected to the external circuit through wires to obtain a fuel-assisted rechargeable battery with high energy density and high power density.

[0010] Preferably, the gas diffusion electrode comprises one or more of carbon fiber, nickel foam and stainless steel mesh.

[0011] Preferably, the catalyst in the gas diffusion electrode is selected from one or more combinations of platinum, platinum black, nickel, iron, copper, silver, gold, palladium, rhodium, rubidium, ruthenium and their alloys; the loading amount of the catalyst is 0.01 mg / cm 2 ~10mg / cm 2 .

[0012] Preferably, the diameter of the gas diffusion channel of the gas diffusion electrode is 0.01 micrometer to 5000 micrometers.

[0013] Preferably, the diaphragm is glass fiber or filter paper;

[0014] The metal film is one or more combinations of magnesium foil, aluminum foil, zinc foil, iron foil, tin foil and alloys thereof.

[0015] Preferably, the electrolyte is a solution of an acid, base or salt, wherein the solute is selected from one or more of potassium hydroxide, sodium hydroxide, zinc acetate, potassium acetate, sodium acetate, zinc sulfate, zinc trifluoromethanesulfonate, and bis[bis(trifluoromethylsulfonyl)imide]zinc, and the solvent is selected from water and / or an organic solvent.

[0016] Preferably, the ventilated housing is made of plastic, stainless steel or aluminum alloy.

[0017] Preferably, the fuel-assisted rechargeable battery performs a discharge step when a gas capable of providing oxygen molecules is introduced; after the gas capable of providing oxygen molecules is switched to fuel gas, the battery is then charged.

[0018] The gas capable of providing oxygen molecules is air, pure oxygen or nitrogen-oxygen mixed gas;

[0019] The fuel gas is hydrogen, carbon monoxide or methane.

[0020] Preferably, the current density of the discharging step is 0.01 to 1000 mA per square centimeter; and the current density of the charging step is 0.01 to 1000 mA per square centimeter.

[0021] The present invention also provides a fuel-assisted rechargeable battery for high energy density and high power density, which is prepared using the preparation method described in the above technical solution.

[0022] The present invention provides a fuel-assisted rechargeable battery (FAR) for high energy density and high power density and a method for its preparation. The method comprises the following steps: assembling a gas diffusion electrode, a separator, and a metal membrane, and then adding an electrolyte to obtain a full battery; the gas diffusion electrode comprises vertical gas diffusion channels and / or three-dimensional disordered gas diffusion channels, with a porosity of 0.1% to 80%; placing the full battery in a ventilated housing, and connecting the positive and negative electrodes to an external circuit via wires, thereby obtaining a FAR for high energy density and high power density. Compared to conventional approaches that optimize electrode structure and develop new catalysts to reduce overpotential and improve round-trip energy efficiency, the technical solution proposed by the present invention radically alters the electrode reactions during charging, significantly reducing the charging voltage and effectively lowering the battery's overpotential. The technical solution provided by the present invention significantly reduces the energy loss of metal-air batteries when charging at high current densities, significantly improves the battery's charging efficiency, and significantly extends the battery life. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] FIG1 is a schematic structural diagram of a fuel-assisted rechargeable battery provided by the present invention;

[0024] FIG2 is a schematic diagram of the charge and discharge implementation of the fuel-assisted rechargeable battery provided by the present invention;

[0025] FIG3 is a voltage-time curve of a fuel-assisted rechargeable battery provided by the present invention during a discharge and charge cycle;

[0026] FIG4 is a voltage-cycle number curve of the fuel-assisted rechargeable battery provided by the present invention;

[0027] FIG5 is a voltage-capacity curve of the fuel-assisted rechargeable battery provided by the present invention under different cycle numbers in hydrogen;

[0028] FIG6 is a voltage-capacity curve of the fuel-assisted rechargeable battery provided by the present invention under different cycle numbers in oxygen. DETAILED DESCRIPTION

[0029] The following will clearly and completely describe the technical solutions of the present invention in conjunction with the embodiments of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0030] The present invention provides a method for preparing a fuel-assisted rechargeable battery with high energy density and high power density, comprising the following steps:

[0031] Assembling a gas diffusion electrode, a diaphragm, and a metal membrane and then adding an electrolyte to obtain a full battery; the gas diffusion electrode has vertical gas diffusion channels and / or three-dimensional disordered gas diffusion channels, and a porosity of 0.1% to 80%;

[0032] The above-mentioned full battery is placed in a ventilated shell, and the positive and negative electrodes are connected to the external circuit through wires to obtain a fuel-assisted rechargeable battery with high energy density and high power density.

[0033] The present invention first assembles a gas diffusion electrode, a diaphragm and a metal membrane, and then adds an electrolyte to obtain a full battery.

[0034] In the present invention, the gas diffusion electrode preferably comprises one or more of carbon fiber, nickel foam, and stainless steel mesh, with carbon fiber being more preferred. The present invention does not particularly limit the source of the gas diffusion electrode; commercially available products or homemade products known to those skilled in the art may be used. In a preferred embodiment of the present invention, the gas diffusion electrode is carbon fiber paper.

[0035] In the present invention, the gas diffusion electrode is loaded with a catalyst. The catalyst is preferably selected from one or more of platinum, platinum black, nickel, iron, copper, silver, gold, palladium, rhodium, rubidium, ruthenium, and alloys thereof, and more preferably platinum black. The present invention does not particularly limit the source of the catalyst; commercially available products known to those skilled in the art may be used.

[0036] In the present invention, the catalyst loading is preferably 0.01 mg / cm 2 ~10mg / cm 2 , more preferably 0.5 mg / cm 2 ~1.5mg / cm 2 .

[0037] In the present invention, the gas diffusion electrode has vertical gas diffusion channels and / or three-dimensional disordered gas diffusion channels, preferably three-dimensional disordered gas diffusion channels; the porosity is 0.1% to 80%;

[0038] In the present invention, the diameter of the gas diffusion channel of the gas diffusion electrode is preferably 0.01 micrometer to 5000 micrometers, more preferably 50 micrometers to 150 micrometers.

[0039] In the present invention, the separator is preferably glass fiber or filter paper, more preferably glass fiber; the metal film is preferably one or more combinations of magnesium foil, aluminum foil, zinc foil, iron foil, tin foil, and alloys thereof, more preferably zinc foil. The sources of the separator and metal film are not particularly limited in the present invention; commercially available products familiar to those skilled in the art may be used.

[0040] In the present invention, the gas diffusion electrode, diaphragm and metal membrane are assembled after cutting; the shapes of the cut gas diffusion electrode, diaphragm and metal membrane can be any shape such as triangle, rectangle, circle, etc., as long as they remain consistent; the thickness of the gas diffusion electrode, diaphragm and metal membrane is preferably 10 microns to 2000 microns, among which the thickness of the gas diffusion electrode is more preferably 50 microns to 150 microns, the thickness of the diaphragm is more preferably 10 microns to 100 microns, and the thickness of the metal membrane is more preferably 150 microns to 250 microns.

[0041] In the present invention, the electrolyte is preferably a solution of an acid, base or salt, more preferably an alkaline solution; wherein the solute is preferably selected from one or more of potassium hydroxide, sodium hydroxide, zinc acetate, potassium acetate, sodium acetate, zinc sulfate, zinc trifluoromethanesulfonate, and bis[bis(trifluoromethylsulfonyl)imide]zinc, more preferably potassium hydroxide; the solvent of the electrolyte is preferably selected from water and / or an organic solvent, more preferably water. The present invention has no particular restrictions on the source of the electrolyte, and commercially available products or homemade products familiar to those skilled in the art can be used. In a preferred embodiment of the present invention, the electrolyte is a 1-10 mol / L potassium hydroxide aqueous solution.

[0042] The present invention has no special limitation on the assembly process, and the technical solutions for assembling battery components well known to those skilled in the art can be adopted.

[0043] In the present invention, the material of the ventilated housing is preferably plastic, stainless steel or aluminum alloy, more preferably stainless steel.

[0044] In the present invention, the fuel-assisted rechargeable battery performs a discharge step when a gas capable of providing oxygen molecules is introduced; after the gas capable of providing oxygen molecules is switched to fuel gas, the battery performs a charging step.

[0045] In the present invention, the gas capable of providing oxygen molecules when the battery is discharged is preferably air, pure oxygen or a nitrogen-oxygen mixture, more preferably pure oxygen; and the fuel gas when the battery is charged is preferably hydrogen, carbon monoxide or methane, more preferably hydrogen.

[0046] In the present invention, the current density of the discharge step is preferably 0.01 to 1000 mA per square centimeter, more preferably 0.5 to 100 mA per square centimeter; the current density of the charge step is preferably 0.01 to 1000 mA per square centimeter, more preferably 200 to 500 mA per square centimeter.

[0047] In the present invention, before the switching, it is preferred that the method further comprises: cleaning with an inert gas; the inert gas is preferably nitrogen.

[0048] The present invention also provides a fuel-assisted rechargeable battery for high energy density and high power density, which is prepared using the preparation method described in the above technical solution.

[0049] The present invention provides a fuel-assisted rechargeable battery technology that can withstand high-power rapid charging. The fuel-assisted rechargeable battery can be used in the automotive industry to improve the charging efficiency and safety of new energy vehicles.

[0050] The present invention provides a fuel-assisted rechargeable battery (FAR) for high energy density and high power density and a method for its preparation. The method comprises the following steps: assembling a gas diffusion electrode, a separator, and a metal membrane, and then adding an electrolyte to obtain a full battery; the gas diffusion electrode comprises vertical gas diffusion channels and / or three-dimensional disordered gas diffusion channels, with a porosity of 0.1% to 80%; placing the full battery in a ventilated housing, and connecting the positive and negative electrodes to an external circuit via wires, thereby obtaining a FAR for high energy density and high power density. Compared to conventional approaches that optimize electrode structure and develop new catalysts to reduce overpotential and improve round-trip energy efficiency, the technical solution proposed by the present invention radically alters the electrode reactions during charging, significantly reducing the charging voltage and effectively lowering the battery's overpotential. The technical solution provided by the present invention significantly reduces the energy loss of metal-air batteries when charging at high current densities, significantly improves the battery's charging efficiency, and significantly extends the battery life.

[0051] To further illustrate the present invention, the following examples are provided for detailed description. In the following examples of the present invention, if no specific conditions are specified, the experiments were carried out according to conventional conditions or those recommended by the manufacturer. Reagents or instruments used, if the manufacturer is not specified, are all commercially available conventional products.

[0052] Example

[0053] Referring to FIG. 1 , FIG. 1 is a schematic structural diagram of a fuel-assisted rechargeable battery provided by the present invention; the fuel-assisted rechargeable battery mainly consists of three parts, namely a gas diffusion electrode, an electrolyte, and a metal foil.

[0054] The specific preparation process is as follows:

[0055] 200 μm thick zinc foil, 50 μm thick glass fiber membrane and 100 μm thick carbon fiber paper loaded with platinum black catalyst were cut into 10 μm diameter discs, where the carbon fiber paper loaded catalyst content was 1 mg / cm 2 , containing three-dimensional disordered gas diffusion channels with a pore size of about 100 microns and a porosity of 50%.

[0056] A fuel-assisted rechargeable battery was assembled in the order of zinc foil, separator, electrolyte and carbon fiber paper, wherein the electrolyte was a 6 mol / L potassium hydroxide aqueous solution.

[0057] Install the assembled battery into a ventilated plastic container and connect it to the external circuit via wires.

[0058] The fuel-assisted rechargeable battery is charged and discharged, as shown in FIG2 . The discharge process is carried out in oxygen, while the charge process is carried out in hydrogen.

[0059] FIG3 shows a voltage-time curve of the fuel-assisted rechargeable battery provided by the present invention during a single discharge and charge cycle. After the battery is discharged in oxygen, the atmosphere inside the battery is first purged with nitrogen and then hydrogen is introduced, and then the charging step is performed in hydrogen.

[0060] The details are as follows:

[0061] The battery was first discharged in an oxygen atmosphere at a current density of 36 milliamperes per square centimeter, resulting in a discharge capacity of 0.5 milliampere-hours per square centimeter. After the discharge, the oxygen was turned off and the interior of the container was purged with nitrogen. The nitrogen was then turned off and hydrogen was introduced. After the open-circuit voltage of the battery dropped below 0.5 volts, the battery was charged at a current density of 360 milliamperes per square centimeter. After the charge was completed, the hydrogen was turned off and nitrogen purging was resumed, and this cycle was repeated. The results are shown in FIG4 (the figure includes the control group, i.e., the information represented by the charging (oxygen) curve. The curve of the battery prepared by the present invention, i.e., the charging (hydrogen) curve, is more stable and has less fluctuation, reflecting the battery's cycling stability, while the curve of the control experimental group has significant fluctuations).

[0062] Furthermore, the battery cycled stably for 100 times under high current density conditions in hydrogen, and was still able to discharge smoothly after 100 cycles. The results are shown in Figure 5. However, under the same charge and discharge conditions, the performance of the battery charged in oxygen deteriorated significantly after 50 cycles, and the discharge capacity decayed severely. The results are shown in Figure 6.

[0063] Through the above experimental results, it can be found that the technical solution provided by the present invention can significantly reduce the charging voltage and prolong the battery life; compared with traditional optimization electrode processes that are complicated and increase production costs, the present invention has the characteristics of low cost, high efficiency and wide application range, and can be widely used in the field of fast charging of new energy vehicles in the future.

[0064] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A preparation method for a fuel-assisted charging battery for high energy density and high power density, characterized in that, It includes the following steps: After assembling the gas diffusion electrode, the separator and the metal film, add the electrolyte to obtain a full cell; The gas diffusion electrode has vertical gas diffusion channels and / or three-dimensional disordered gas diffusion channels, and the porosity is 0.1% to 80%; Put the above full cell into a ventable outer shell, and connect the positive and negative electrodes to the external circuit through wires to obtain a fuel-assisted rechargeable battery for high energy density and high power density.

2. The preparation method according to claim 1, wherein The gas diffusion electrode includes one or more of carbon fiber, nickel foam and stainless steel mesh.

3. The preparation method according to claim 1, characterized in that, The catalyst in the gas diffusion electrode is selected from one or more combinations of platinum, platinum black, nickel, iron, copper, silver, gold, palladium, rhodium, rubidium, ruthenium and their alloys; the loading amount of the catalyst is 0.01 mg / cm 2 ~10 mg / cm 2 .

4. The preparation method according to claim 1, characterized in that, The diameter of the gas diffusion channels of the gas diffusion electrode is 0.01 micrometer to 5000 micrometers.

5. The preparation method according to claim 1, wherein The separator is glass fiber or filter paper; The metal film is one or more combinations of magnesium foil, aluminum foil, zinc foil, iron foil, tin foil and their alloys.

6. The preparation method according to claim 1, characterized in that, The electrolyte is a solution of acid, alkali or salt, wherein the solute is selected from one or more of potassium hydroxide, sodium hydroxide, zinc acetate, potassium acetate, sodium acetate, zinc sulfate, zinc trifluoromethanesulfonate, zinc bis(trifluoromethylsulfonyl)imide, and the solvent is selected from water and / or organic solvents.

7. The preparation method according to claim 1, wherein The material of the ventable outer shell is plastic, stainless steel or aluminum alloy.

8. The preparation method according to claim 1, characterized in that, When the fuel-assisted rechargeable battery is supplied with a gas that can provide oxygen molecules, a discharging step is carried out; after switching the gas that can provide oxygen molecules to a fuel gas, the battery is then charged; The gas that can provide oxygen molecules is air, pure oxygen or nitrogen-oxygen mixture; The fuel gas is hydrogen, carbon monoxide or methane.

9. The preparation method according to claim 8, characterized in that, The current density of the discharging step is 0.01 to 1000 milliamperes per square centimeter; the current density of the charging step is 0.01 to 1000 milliamperes per square centimeter.

10. A fuel-assisted charging battery for high energy density and high power density, characterized in that, It is prepared by using the preparation method according to any one of claims 1 to 9.

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