Organic negative electrode and metal-air battery

Abstract

The application provides an organic negative electrode and a metal-air battery, the organic negative electrode comprises an organic matter with a low redox potential, the organic matter with the low redox potential comprises phenazine, diquinoxaline phenazine, a nitrogen heterocyclic ring, a carboxylate or an azo compound, the organic matter in the organic negative electrode is corrosion resistant and the redox potential can be adjusted, even reaching a negative reduction potential comparable to that of hydrogen, so that the phenomenon of hydrogen evolution corrosion cannot occur; a large number of functional groups and active sites in the organic matter can induce uniform deposition of metal ions, and there is no condition for dendrite growth and formation of a passivation layer, so that various problems caused by the above metal negative electrode can be completely avoided; the metal-air battery with the above organic negative electrode has the advantages of long cycle time, stable performance, safety, environmental protection and low cost, and has a wide application prospect in the field of large-scale energy storage.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of batteries, in particular to an organic negative electrode and a metal-air battery. BACKGROUND

[0002] Recently, metal-air batteries have broad development prospects as a safe and environmentally friendly energy technology, with the advantages of high energy density, low cost, safety and environmental protection. However, the surface passivation, dendrite growth and hydrogen evolution corrosion of the metal negative electrode during use seriously restrict the commercialization process of aqueous metal-air batteries.

[0003] The passivation process of the metal negative electrode is mainly due to the large amount of supersaturated oxidizing substance on the surface of the metal negative electrode, which terminates the discharge process, prevents the reduction of metal ions, and reduces the battery capacity and utilization of the metal-air battery.

[0004] Dendrite growth is mainly caused by the uneven deposition of metal ions on the surface of the metal negative electrode. The large growth and shedding of dendrites can cause short circuit, capacity decay and short service life of the battery. Generally, physical isolation of the electrolyte from the metal electrode or changing the deposition behavior of zinc in the electrolyte is used to solve the dendrite problem; hydrogen evolution corrosion mainly occurs when the metal has a larger negative reduction potential than hydrogen, and the hydrogen evolution reaction can occur spontaneously in the aqueous electrolyte. For example, the thermodynamic instability of zinc metal in alkaline electrolyte leads to the evolution of hydrogen, so that the zinc-air battery is in low power consumption even in the case of no load.

[0005] Current strategies to solve the above problems mainly include:

[0006] (1) Inhibit the passivation of the metal electrode by adjusting the electrolyte composition. First, the formation of the metal oxide passivation layer is generally inhibited by increasing the concentration of the electrolyte, adding a surfactant, and using a liquid flow to dissolve and destroy the structure of the passivation layer. Second, organic or inorganic additives are added to the electrolyte to improve the deposition behavior of metal ions to inhibit the growth of dendrites. In addition, inorganic or organic corrosion inhibitors are added to the electrode or electrolyte to form an adsorption layer on the surface of the metal negative electrode to enhance the hydrogen evolution overpotential of the negative electrode, thereby inhibiting the corrosion and hydrogen evolution of the metal negative electrode.

[0007] (2) Inhibit the formation of surface passivation and dendrites by developing new modified metal negative electrodes. The main methods are to prevent passivation and maintain the durability of the material during charge and discharge cycles by designing porous metal negative electrodes, coating the surface of metal negative electrode powder, and adjusting the size of metal powder particles.

[0008] The above-mentioned technology, although alleviates the passivation, dendrite growth and hydrogen evolution corrosion problems in the metal-air battery to some extent, but due to the intrinsic property of metal (such as zinc metal) has a larger negative reduction potential than hydrogen, resulting in these problems cannot be fundamentally solved completely. SUMMARY

[0009] In view of this, it is necessary to provide an organic negative electrode and a metal-air battery which can solve the problems of passivation, dendrite and hydrogen evolution on the surface of the traditional metal negative electrode in view of the defects existing in the prior art.

[0010] To solve the above problems, the technical scheme adopted by the present application is as follows:

[0011] One of the purposes of the present application is to provide an organic negative electrode, which comprises an organic material with a low redox potential, and the organic material with a low redox potential comprises phenazine, diquinoxaline phenazine, nitrogen heteroaromatic ring, carboxylic acid or azo compound.

[0012] In some embodiments, the nitrogen heteroaromatic ring is prepared by the following steps:

[0013] Under the protection of Ar or N2 gas, o-diamino ligand and cyclohexanehexone are dissolved in a mixed liquid of acetonitrile and acetic acid, and then stirred and condensed under reflux at a temperature of 100-160°C for 6-36 hours. After stopping heating and cooling to room temperature, the solid after reaction is extracted by suction filtration or centrifugation;

[0014] After washing and drying the solid after reaction, a 20-30% concentration of nitric acid solution is added and reacted at a temperature of 140-170°C for 2-3 hours. After cooling, the product is separated by filtration or centrifugation, and the solid component is collected.

[0015] After washing and drying the solid component, the nitrogen heteroaromatic ring is obtained.

[0016] In some embodiments, the molar ratio of the o-diamino ligand to cyclohexanehexone is 2-6:1.

[0017] In some embodiments, the o-diamino ligand comprises o-phenylenediamine or 2,3-diaminophenazine or 3,4-diaminobenzonitrile.

[0018] In some embodiments, the carboxylic acid material comprises terephthalic acid, and the azo compound comprises azobenzene, azobenzene 4,4-dicarboxylic acid or p-dimethylaminobenzene azo phthalic acid.

[0019] The second purpose of the present application is to provide a metal-air battery comprising any one of the organic negative electrodes.

[0020] In some embodiments, the metal-air battery further comprises an air cathode, the air cathode comprising a dual-function catalyst with oxygen decomposition and oxygen reduction, the dual-function catalyst comprising a platinum-carbon composite, yttrium oxide, a polyphthalocyanine compound.

[0021] In some embodiments, the polyphthalocyanine compound is prepared by the following steps:

[0022] After the organic ligand, the metal compound, the ammonium chloride and the ammonium molybdate are mixed uniformly, and heated to 220-440℃ under Ar or N2 or air protection for 2-5 hours, and then cooled to room temperature, the obtained solid mixture is obtained;

[0023] After the solid mixture is washed and vacuum dried, the polyphthalocyanine compound is obtained.

[0024] In some embodiments, the organic ligand comprises at least one of phthalic anhydride, pyromellitic anhydride, urea.

[0025] In some embodiments, the metal compound comprises at least one of a metal chloride or a metal nitrate or a metal acetate.

[0026] In some embodiments, the molar ratio of the organic ligand and the metal compound is 1-10:1, the mass ratio of the organic ligand and the ammonium chloride is 5-10:1, and the addition amount of the ammonium molybdate is 0.5-1wt% of the addition amount of the organic ligand.

[0027] In some embodiments, the metal-air battery further comprises an alkaline aqueous electrolyte, the alkaline aqueous electrolyte comprising an electrolyte and an electrolyte, the electrolyte comprising at least one of potassium hydroxide, potassium acetate, potassium trifluoromethyl sulfonate, and the electrolyte comprising a full water electrolyte or an organic-water hybrid electrolyte.

[0028] In some embodiments, the organic in the organic-water hybrid electrolyte comprises 1,3-dioxolane, ethylene glycol dimethyl ether, acetonitrile, dimethyl sulfoxide, and carbonate organic.

[0029] The application adopts the above technical solution, and has the following beneficial effects:

[0030] The organic negative electrode provided by the application comprises an organic matter with a low redox potential, and the organic matter with a low redox potential comprises phenazine, diquinoxaline phenazine, nitrogen heteroaromatic ring, carboxylate or azo compound. The organic matter in the organic negative electrode is corrosion resistant and the redox potential can be adjusted, and even can reach a negative reduction potential comparable to that of hydrogen, so that the phenomenon of hydrogen evolution corrosion will not occur. The organic matter has a large number of functional groups and active sites, which can induce uniform deposition of metal ions, and does not have the conditions of dendrite growth and passivation layer formation, so that various problems caused by the above metal negative electrode can be completely avoided. The metal air battery with the above organic negative electrode has the advantages of long cycle time, stable performance, safety, environmental protection and low cost, and has a broad application prospect in the field of large-scale energy storage. BRIEF DESCRIPTION OF DRAWINGS

[0031] In order to more clearly illustrate the technical solutions of the embodiments of the application, the drawings needed to be used in the embodiments of the application or the prior art description will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the application, and other drawings can be obtained by those skilled in the art without creative labor on the basis of these drawings.

[0032] Figure 1 The XRD graph of the nitrogen heteroaromatic ring organic material provided for example 1 is shown in the figure;

[0033] Figure 2 The FT-IR graph of the nitrogen heteroaromatic ring organic material provided for example 1 is shown in the figure;

[0034] Figure 3 The SEM graph of the nitrogen heteroaromatic ring material provided for example 1 is shown in the figure;

[0035] Figure 4 The structure schematic diagram of the nitrogen heteroaromatic ring organic electrode-air battery provided for example 2 is shown in the figure;

[0036] Figure 5 The cycle-capacity graph of the nitrogen heteroaromatic ring organic electrode-air battery provided for example 2 is shown in the figure;

[0037] Figure 6 The rate-capacity graph of the nitrogen heteroaromatic ring organic electrode-air battery in different electrolytes is shown in the figure. DETAILED DESCRIPTION

[0038] The embodiments of the application will be described in detail below, and examples of the embodiments are shown in the drawings, wherein the same or similar reference signs represent the same or similar elements or elements with the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary and are intended to explain the application, and cannot be understood as a limitation of the application.

[0039] In the description of the present application, it needs to be understood that the terms "upper", "lower", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0040] In addition, the terms "first", "second" are only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features referred to. Therefore, the features defined as "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "multiple" is two or more, unless otherwise explicitly and specifically limited.

[0041] In order to make the purpose, technical scheme and advantages of the present application more clear, the present application is further described in detail below in combination with the drawings and examples.

[0042] The present application provides an organic negative electrode, which comprises an organic material with a low redox potential, and the organic material with a low redox potential comprises phenazine, diquinoxaline phenazine, nitrogen heteroaromatic ring, carboxylate or azo compound.

[0043] In some embodiments, the carboxylic acid material comprises terephthalic acid, and the azo compound comprises azobenzene, azobenzene 4,4-dicarboxylic acid or p-dimethylaminobenzene azo phthalic acid.

[0044] In some embodiments, the nitrogen heteroaromatic ring is prepared by the following steps S110 to S130, and the specific implementation of each step is described in detail below.

[0045] Step S110: Dissolve the o-diamino ligand and cyclohexanehexone in a mixed liquid of acetonitrile and acetic acid under Ar or N2 gas protection, then stir and condense reflux at a temperature of 100-160°C for 6-36 hours, stop heating, cool to room temperature, and extract the solid after reaction by suction filtration or centrifugation.

[0046] In the present embodiment, the molar ratio of the o-diamino ligand to cyclohexanehexone is 2-6:1.

[0047] In the present embodiment, the o-diamino ligand comprises o-phenylenediamine or 2,3-diaminophenazine or 3,4-diaminobenzonitrile.

[0048] Step S120: after washing and drying the reacted solid, the solid is reacted with a 20-30% concentration nitric acid solution at a temperature of 140-170°C for 2-3 hours, and after cooling, the product is separated by filtration or centrifugation, and the solid component is collected.

[0049] In this embodiment, the washing includes sequentially washing the reacted solid with acetone, water, and ethanol.

[0050] Step S130: after washing and drying the solid component, the azaheterocyclic compound is obtained.

[0051] In this embodiment, the washing includes sequentially washing the solid component with acetone, water, and ethanol.

[0052] It can be understood that in practice, the above-mentioned organic negative electrode further includes conductive carbon and a binder.

[0053] In this embodiment, the organic negative electrode includes 60wt%-85wt% azaheterocyclic organic material, 15wt%-30wt% conductive carbon, and 0wt%-10wt% binder.

[0054] The organic negative electrode provided by the present application includes an organic material with a low redox potential, and the organic material with a low redox potential includes phenazine, diquinoxaline phenazine, azaheterocyclic compound, carboxylate, or azo compound. The organic material has the natural properties of corrosion resistance and low redox potential, can match the air electrode to form a potential difference suitable for the voltage window of the aqueous electrolyte, and can solve the phenomenon of hydrogen evolution corrosion. The organic negative electrode has a large number of functional groups and active sites, can induce uniform deposition of metal ions, does not have the conditions for dendrite growth and passivation layer formation, and can completely avoid various problems faced by the above metal negative electrode.

[0055] The present application also provides a metal-air battery including the organic negative electrode, and the specific implementation scheme of the organic negative electrode has been described in detail above and will not be described here.

[0056] In this embodiment, the metal-air battery further includes an air positive electrode, and the air positive electrode includes a double-function catalyst including platinum-carbon composite material, yttrium oxide, and polyphthalocyanine compound.

[0057] In this embodiment, the polyphthalocyanine compound is prepared by the following steps:

[0058] Step S210: after grinding and uniformly mixing an organic ligand, a metal compound, ammonium chloride, and ammonium molybdate, the mixture is heated to 220-440°C under Ar or N2 gas or air protection for 2-5 hours, and then cooled to room temperature to obtain a solid mixture.

[0059] In the embodiment, the organic ligand comprises at least one of phthalic anhydride, pyromellitic anhydride, urea.

[0060] In the embodiment, the metal compound comprises at least one of metal chloride or metal nitrate or metal acetate.

[0061] In the embodiment, the molar ratio of the organic ligand and the metal compound is 1-10:1, the mass ratio of the organic ligand and ammonium chloride is 5-10:1, and the addition amount of the ammonium molybdate is 0.5-1 wt% of the addition amount of the organic ligand.

[0062] Step S220: vacuum drying the solid mixture after washing to obtain the polyphthalocyanine compound.

[0063] In the embodiment, the washing comprises washing the solid mixture with deionized water, acetone and ethanol in sequence to remove the reactants not participating in the reaction.

[0064] It can be understood that, in practice, the air positive electrode provided in the embodiment further comprises conductive carbon and a binder.

[0065] In the embodiment, the air positive electrode comprises 60 wt%-85 wt% of the bifunctional catalyst, 15 wt%-30 wt% of the conductive carbon and 0 wt%-10 wt% of the binder.

[0066] In the embodiment, the metal-air battery further comprises an alkaline aqueous electrolyte, and the alkaline aqueous electrolyte comprises an electrolyte and an electrolyte solution, the electrolyte comprises at least one of potassium hydroxide, potassium acetate and potassium trifluoromethylsulfonate, and the electrolyte solution comprises a full water electrolyte solution or an organic-water hybrid electrolyte solution.

[0067] In the embodiment, the organic in the organic-water hybrid electrolyte solution comprises 1,3-dioxolane, ethylene glycol dimethyl ether, acetonitrile, dimethyl sulfoxide and carbonate organic.

[0068] It can be understood that, in the metal-air battery provided in the application, the nitrogen heteroaromatic organic material (bifunctional catalyst), conductive carbon and binder are mixed in a solvent in a suitable proportion to form a viscous substance, which is coated on a current collector carbon cloth or carbon paper (waterproof and air-permeable carbon cloth) and vacuum dried at a temperature of 60-110°C for 12-24 hours to remove the solvent. The cutting machine is used to cut the viscous substance into a suitable size as the negative electrode (positive electrode) sheet of the battery, and a suitable separator and electrolyte solution are selected to assemble the battery.

[0069] The metal air battery provided by the application is assembled by matching the nitrogen heteroaromatic ring organic material as the negative electrode, the polyphthalocyanine catalyst material as the positive electrode, and the alkaline aqueous solution as the electrolyte, has stable cycle performance, is safe and environmentally friendly, is low in cost, and has a wide application prospect in large-scale energy storage.

[0070] The above technical solutions of the application are described in detail below in combination with specific embodiments.

[0071] Embodiment 1

[0072] The preparation method of the metal air battery provided in this embodiment 1 includes the following steps:

[0073] (1) The o-phenylenediamine and cyclohexanehexaketone are weighed according to a molar ratio of 3.5:1, dissolved in an acetic acid solution under the protection of Ar gas, and condensed and refluxed under the condition of 120℃ and magnetic stirring for 24 hours. Then, the heating is stopped, the condensation is cooled to room temperature, the post-reaction solid is extracted by suction filtration, and the post-reaction solid is sequentially cleaned with acetone, water, and ethanol. After drying, the post-reaction solid is added to a 30% concentration nitric acid solution, reacted at 140℃ for 3 hours, separated by filtration after cooling, sequentially cleaned with acetone, water, and ethanol again, and dried to obtain the nitrogen heteroaromatic ring organic material (HATN). The X-ray diffraction data of the nitrogen heteroaromatic ring organic material HATN are shown in the following table. Figure 1 The infrared data of HATN are shown in the following table. Figure 2 The infrared data of HATN are shown in the following table. Figure 3 The morphology of HATN is observed by SEM, and the material presents a rod-shaped structure morphology as shown in the following figure.

[0074] (2) The o-phthalic anhydride and pyromellitic anhydride are weighed according to a mass ratio of 1:2, put into a mortar, and then the cobalt chloride, ammonium chloride, and urea are added according to a mass ratio of 1:2:8, mixed uniformly, a small amount of ammonium molybdate is added, the solid is ground and mixed again uniformly, put into a porcelain boat, and transferred to a tube furnace. After being heated to 220℃ under the protection of Ar or N2 gas for a period of time and cooled to room temperature, the obtained solid is sequentially cleaned with deionized water, acetone, and ethanol to remove the unreacted reactants, and vacuum dried overnight to obtain a defective polyphthalocyanine cobalt compound.

[0075] (3) The preparation method of the nitrogen heteroaromatic ring organic negative electrode sheet (defect type polyphthalocyanine cobalt-based positive electrode sheet) comprises the following steps: nitrogen heteroaromatic ring organic material (defect type polyphthalocyanine cobalt-based compound), conductive carbon and binder polyvinylidene fluoride are weighed according to a mass ratio of 6:3:1, respectively, placed in a mortar, an organic solvent N-methyl pyrrolidone is added to mix into a thick slurry, which is coated on carbon cloth (waterproof and breathable carbon cloth), vacuum dried at a temperature of 80°C for 12 hours to remove the organic solvent. A cutting machine is used to cut it to 2cm 2 in size, that is, a nitrogen heteroaromatic ring organic negative electrode sheet (defect type polyphthalocyanine cobalt-based positive electrode sheet) is prepared.

[0076] (4) Prepare alkaline electrolyte with different concentrations and electrolytes. ① 4M concentration of alkaline potassium hydroxide electrolyte, ② 4M concentration of mixed solution of potassium hydroxide and 10M potassium trifluoromethyl sulfonate electrolyte, ③ 4M concentration of mixed solution of potassium hydroxide and 16M potassium acetate electrolyte. The mass of the added electrolyte and the mass of the aqueous solution are shown in the following table:

[0077] Table 1 Preparation method of alkaline electrolyte with different concentrations and electrolytes

[0078] M (KOH / g) [M (KCF3SO3 / g)] M (KoAc / g) [M (H20 / g)] Electrolyte 1 22.44 — — 100 Electrolyte 2 22.44 188.1 — 100 Electrolyte 3 22.44 — 157.024 100

[0079] Example 2

[0080] This example 2 provides the assembly of a metal-air battery and its performance test:

[0081] (1) Battery assembly: the negative electrode sheet made of the nitrogen heteroaromatic ring organic electrode material prepared by the application, the positive electrode sheet of the defect type polyphthalocyanine cobalt material, the separator is a cellulose separator, the electrolyte is a mixed solution of 4M potassium hydroxide and 10M potassium trifluoromethyl sulfonate, and an organic electrode-air battery is assembled by using a fuel cell reactor. The schematic diagram of the battery is shown in Figure 4 .

[0082] (2) Electrochemical test: under room temperature conditions, the prepared organic electrode-air battery is subjected to charge and discharge test on a new wei battery test system, the charge and discharge voltage interval is 0.1-1.6V, and the charge and discharge test is carried out at a current density of 20A / g. The cycle-capacity diagram of the nitrogen heteroaromatic ring-air battery is shown in Figure 5 , and the electrochemical performance test shows that the specific capacity of the electrode material can reach 20mAh g -1 , and can be cycled more than 30000 times.

[0083] Example 3

[0084] This example 3 provides the assembly of a metal-air battery and its performance test.

[0085] (1) Cell assembly: The difference between Example 3 and Example 2 is that the electrolyte in Step 1 is a mixed solution of 4M potassium hydroxide and 16M potassium acetate.

[0086] (2) Electrochemical test: The prepared organic electrode-air battery was subjected to charge-discharge test on a Neware battery test system at room temperature, and the charge-discharge voltage interval was 0.1-1.6V. The rate charge-discharge test was carried out at different current densities of 1A g -1 , 2A g -1 , 5A g -1 , 10A g -1 , 20A g -1 , 30A g -1 , 40A g -1 , 50A g -1 , 80A g -1 and 100A g -1 . The rate cycle diagram of azaheterocyclic ring-air battery in different electrolytes is shown in Figure 6 , and the electrochemical performance test shows that the specific capacity of the air battery in the mixed solution electrolyte of 4M potassium hydroxide and 10M potassium trifluoromethylsulfonate ② is higher than that in the mixed solution electrolyte of 4M potassium hydroxide and 16M potassium acetate ③ under the same conditions, and the specific capacity is shown in Table 2 as follows:

[0087] Table 2 Comparison of rate performance of organic electrode-air battery in different electrolytes

[0088] 1Ag -1 ]]> 2 5 10 20 30 40 50 80 100 2 specific capacity 250 237 218 195 172 158 148 141 118 101 3 specific capacity 246.7 226 127.4 37.2 12.4 4.25 0 0 0 0

[0089] The above only describes the preferred embodiments of the present application, and any changes and modifications made within the scope of the patent application of the present application shall be included in the scope of the present application.

[0090] It can be understood that the technical features of the above-described embodiments can be combined in any way. In order to make the description simple, all possible combinations of the technical features in the above-described embodiments are not described, however, as long as the combination of the technical features does not exist contradictory, it should be considered as the scope of the present application.

[0091] The above only describes the preferred embodiments of the present application, and only the technical principles of the present application are described. These descriptions are only to explain the principles of the present application, and cannot be interpreted as limiting the protection scope of the present application in any way. Based on the explanations here, any modifications, equivalent replacements and improvements made within the spirit and principles of the present application, and other specific embodiments of the present application that can be easily thought of by those skilled in the art without creative labor, shall be included in the protection scope of the present application.

Claims

1. An air battery, characterized in that, include: Nitrogen-containing aromatic ring organic negative electrode, defective polyphthalocyanine cobalt positive electrode, separator and electrolyte; The nitrogen-containing aromatic ring organic negative electrode sheet is prepared by the following steps: o-phenylenediamine and cyclohexanehexaone are weighed in a molar ratio of 3.5:1, dissolved in acetic acid solution under Ar protection, and refluxed at 120°C with magnetic stirring for 24 hours. Heating is then stopped, and the mixture is cooled to room temperature. The solid after reaction is extracted by vacuum filtration. The solid is washed sequentially with acetone, water, and ethanol, dried, and then added to a 30% nitric acid solution. The reaction is carried out at 140°C for 3 hours. After cooling, the product is separated by filtration. The solid is washed again sequentially with acetone, water, and ethanol, and dried to obtain the nitrogen-containing aromatic ring organic material. The nitrogen-containing aromatic ring organic material, conductive carbon, and binder polyvinylidene fluoride are weighed in a mass ratio of 6:3:1, placed in a mortar, and mixed with the organic solvent N-methylpyrrolidone to form a viscous slurry. This slurry is coated onto carbon cloth and vacuum dried at 80°C for 12 hours to remove the organic solvent. The slurry is then cut to 2 cm using a cutting machine. 2 Size, i.e., the preparation of nitrogen-containing aromatic ring organic negative electrode plates; The defective polyphthalocyanine cobalt-based positive electrode sheet is prepared by the following steps: Phthalic anhydride and pyromellitic anhydride are weighed in a mass ratio of 1:2 and placed in a mortar. Cobalt chloride, ammonium chloride, and urea are added in a mass ratio of 1:2:8 and mixed evenly. Then, ammonium molybdate is added, and the solid is ground and mixed evenly again. The mixture is placed in a ceramic boat and transferred to a tube furnace. Under Ar or N2 gas protection, it is heated to 220°C and held for a period of time. After cooling to room temperature, the obtained solid is washed sequentially with deionized water, acetone, and ethanol to remove unreacted reactants. It is then vacuum dried overnight to obtain the defective polyphthalocyanine cobalt compound. The defective polyphthalocyanine cobalt compound, conductive carbon, and binder polyvinylidene fluoride are weighed in a mass ratio of 6:3:1 and placed in a mortar. The organic solvent N-methylpyrrolidone is added and mixed to form a viscous slurry. This slurry is coated onto waterproof and breathable carbon cloth and vacuum dried at 80°C for 12 hours to remove the organic solvent. The slurry is then cut to 2mm using a cutting machine. cm 2 The size, i.e., the preparation of the defective polyphthalocyanine cobalt-based positive electrode sheet; The diaphragm is a cellulose diaphragm; The electrolyte is a mixed solution of 4 M potassium hydroxide and 10 M potassium trifluoromethanesulfonate.

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