Preparation method of water-based manganese ion energy storage capable of being charged by temperature difference

Abstract

The present application relates to the technical field of aqueous manganese ion energy storage, and particularly relates to a preparation method of an aqueous manganese ion energy storage device capable of temperature difference charging, and the preparation steps comprise the following steps: S1, mixing a manganese triflate solution and a manganese perchlorate solution to obtain an electrolyte; S2, mixing bismuth telluride, acetylene black and polyvinylidene fluoride to prepare a slurry, coating the slurry on cut graphite paper, and drying to obtain a bismuth telluride positive electrode; S3, ultrasonicating and drying a metal foil to obtain a negative electrode; and S4, assembling the electrolyte, the positive electrode and the negative electrode to obtain the energy storage device. The present application improves the cycle stability of the positive electrode of the manganese ion energy storage device, enables the manganese ion energy storage device to have high reversible specific capacity and long cycle life, and exhibits excellent electrochemical performance.

Description

Technical Field

[0001] This invention relates to the field of aqueous manganese ion energy storage technology, specifically to a method for preparing an aqueous manganese ion energy storage device that can be charged by temperature difference. Background Technology

[0002] With the rapid development of wearable technology and integrated electronic products, the demand for safe and miniaturized energy storage devices (ESD) is increasing. Furthermore, the direct emission of large amounts of low-grade heat (<100 ℃) generated by solar radiation and human production and daily life into the environment leads to significant energy waste and severe thermal pollution. Therefore, developing power systems with low cost, high performance, sustainability, and good durability is extremely necessary for the development of human production and daily life.

[0003] Although low-grade heat energy (below 373 K) is a ubiquitous and inexhaustible energy source with enormous potential for sustainable power generation, it remains largely underutilized. Traditional electronic thermoelectric devices (e-TE) show potential over a wide temperature range, but their poor Seebeck coefficient and the complexity of integrating individual devices significantly limit their development. Ionizing thermoelectric devices (i-TE), as an emerging thermoelectric technology, possess unique advantages such as high thermal power, cost-effectiveness, ease of manufacturing, and high energy output, showing great promise in low-grade heat conversion. Currently, lithium-ion energy storage devices are the most widely used ion energy storage devices; however, the flammability of their electrolytes and the scarcity of lithium resources hinder the application of lithium-ion energy storage devices in ionizing thermoelectric devices, and similarly, their application in large-scale energy storage. Aqueous rechargeable energy storage devices not only solve safety issues but also offer lower resource costs. Aqueous rechargeable energy storage devices with copper (Cu), iron (Fe), magnesium (Mg), zinc (Zn), and manganese (Mn) metal anodes are rapidly developing, with manganese exhibiting unique advantages among these metals.

[0004] Manganese resources are abundant, and manganese ion energy storage devices (Mn ion energy storage devices) possess high capacity (976 mAh / g), high safety, and low redox potential (-1.19 V, relative to the standard hydrogen electrode) have attracted considerable attention. Traditional Mn metal energy storage devices suffer from irreversible capacity decay at the Mn anode due to the influence of aqueous electrolytes. Although using hydrated eutectic electrolytes can suppress the hydrogen evolution reaction, the addition of organic solvents reduces ionic conductivity. Furthermore, alloying manganese cannot completely mitigate the irreversibility of the Mn anode. Therefore, there is an urgent need to explore new energy storage device structures that combine Mn ion energy storage devices with thermoelectric technology to aid in decarbonization and improve economic and environmental benefits. Based on this, this application provides a method for preparing a thermoelectrically rechargeable aqueous manganese ion energy storage device. Summary of the Invention

[0005] This invention improves the cycle stability of the positive electrode of the manganese ion energy storage device, enabling the manganese ion energy storage device to have high reversible specific capacity and long cycle life, exhibiting excellent electrochemical performance.

[0006] This invention provides a method for fabricating a thermoelectrically rechargeable aqueous manganese ion energy storage device. Utilizing the characteristic that the binding energy between trifluoromethanesulfonate anions and manganese ions is lower than that between water molecules and manganese ions, the device seizes the binding sites between water molecules and manganese ions, altering the solvation structure of manganese ions and reducing the desolvation energy. Furthermore, manganese perchlorate anions diffuse rapidly on the surface of bismuth telluride, quickly adhering to the surface and preventing corrosion of bismuth telluride by trifluoromethanesulfonate anions. Additionally, the positive electrode material is a topological insulator, exhibiting surface or boundary conductivity but non-conductivity internally, resulting in no energy loss during carrier transport.

[0007] To achieve this objective, the present invention adopts the following technical solution:

[0008] This invention provides a method for preparing a thermoelectrically rechargeable aqueous manganese ion energy storage device, comprising the following steps:

[0009] S1. An electrolyte is obtained by mixing manganese trifluoromethanesulfonate solution and manganese perchlorate solution.

[0010] S2. Bismuth telluride, acetylene black and polyvinylidene fluoride are mixed to prepare a slurry. The slurry is coated on a cut graphite paper and dried to obtain a bismuth telluride cathode.

[0011] S3. The metal foil is ultrasonically and dried to obtain the negative electrode;

[0012] S4. The energy storage device is obtained by assembling the electrolyte, positive electrode and negative electrode.

[0013] Further, the manganese trifluoromethanesulfonate solution is an aqueous solution of manganese trifluoromethanesulfonate with a concentration of 1-2 mol / L; the manganese perchlorate solution is an aqueous solution of manganese perchlorate with a concentration of 1-2 mol / L.

[0014] Furthermore, the method for preparing the manganese trifluoromethanesulfonate solution is as follows: weigh manganese trifluoromethanesulfonate, put it into a beaker containing deionized water, stir at 800-1000 rpm for 20-40 minutes to obtain the manganese trifluoromethanesulfonate solution.

[0015] Furthermore, the method for preparing the manganese perchlorate solution is as follows: weigh manganese perchlorate, put it into a beaker containing deionized water, stir at 800-1000 rpm for 20-40 minutes to obtain the manganese perchlorate solution.

[0016] Furthermore, the electrolyte is prepared by mixing manganese trifluoromethanesulfonate solution and manganese perchlorate solution, stirring at 800-1000 rpm for 1-2 hours.

[0017] Furthermore, the volume ratio of the manganese trifluoromethanesulfonate solution to the manganese perchlorate solution is 3-7:3-7.

[0018] Furthermore, the weight ratio of bismuth telluride, acetylene black, and polyvinylidene fluoride is 10.5-21:3-6:1.5-3.

[0019] Furthermore, the drying temperature in S2 is 50-60℃, and the drying time is 40-60 min.

[0020] Further, the preparation method of the bismuth telluride includes: adding polyvinylpyrrolidone to ethylene glycol, mixing, stirring at 1500-2000 rpm for 6-10 hours until the solution is transparent, adding sodium hydroxide, tellurium dioxide and bismuth trichloride, stirring at 1500-2000 rpm for 3-6 hours until the solution is transparent; transferring to a reaction vessel, carrying out a hydrothermal reaction, and after the reaction is completed, washing and drying to obtain the bismuth telluride.

[0021] Furthermore, the ratio of polyvinylpyrrolidone, ethylene glycol, sodium hydroxide, tellurium dioxide and bismuth trichloride is 0.4-0.8g: 25-50mL: 0.5-1.0g: 0.24-0.48g: 0.315-0.63g.

[0022] Furthermore, the hydrothermal reaction temperature is 180-220℃, and the reaction time is 9-12 hours.

[0023] Furthermore, the cleaning process involves multiple cleaning cycles using anhydrous ethanol and deionized water, respectively.

[0024] Furthermore, the metal foil is a zinc metal foil, and the ultrasound in S3 is performed by ultrasound in anhydrous ethanol for 10-30 minutes.

[0025] The advantages of this invention are:

[0026] In this invention, a thermoelectrically rechargeable aqueous manganese ion energy storage device utilizes trifluoromethanesulfonate ions. Because the binding energy between trifluoromethanesulfonate ions and manganese ions is lower than that between water molecules and manganese ions, the solvation structure of manganese ions is altered. This facilitates desolvation of manganese ions during storage, making them easier to embed into the bismuth telluride cathode material. Furthermore, there is no energy loss in carrier transport on the surface of the bismuth telluride cathode material, thus improving the capacity and thermal conversion efficiency of the manganese ion energy storage device. In addition, since perchlorate ions diffuse to the surface of the bismuth telluride cathode material faster than trifluoromethanesulfonate ions, the cathode material is protected from corrosion by trifluoromethanesulfonate ions, thereby improving the cycle stability of the manganese ion energy storage device's cathode. This results in a high reversible specific capacity and long cycle life, exhibiting superior electrochemical performance.

[0027] The thermoelectrically rechargeable aqueous manganese ion energy storage device of the present invention provides a high reversible capacity of 400 mAh / g at a current density of 0.5 A / g.

[0028] The aqueous manganese ion energy storage device of this invention reduces the energy required for manganese ion desolvation by substituting water molecules with trifluoromethanesulfonate ions, thus avoiding the problem of difficult manganese ion intercalation. Furthermore, the addition of perchlorate ions increases the pH of the electrolyte, allowing perchlorate ions to diffuse more quickly to the bismuth telluride surface, avoiding the problem of the positive electrode being easily corroded by trifluoromethanesulfonate ions. This achieves rapid ion diffusion kinetics and high cycling stability in the manganese ion energy storage device.

[0029] When the electrolyte of this invention is applied to an aqueous manganese ion energy storage device, it can be used for thermoelectric power generation, which has the advantages of being environmentally friendly and highly safe, and has great application potential in the field of electrochemistry. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0031] Figure 1 This is a schematic diagram of the thermoelectrically rechargeable aqueous manganese ion energy storage device provided by the present invention.

[0032] Figure 2 These are Raman spectra of different electrolytes used in the aqueous manganese ion energy storage device of this invention;

[0033] Figure 3 These are the electrochemical impedance spectra and calculated conductivity of different electrolytes used in the aqueous manganese ion energy storage device of this invention;

[0034] Figure 4 This is an X-ray diffraction pattern of bismuth telluride, the positive electrode material used in the aqueous manganese ion energy storage device of this invention.

[0035] Figure 5 This is a scanning electron microscope image of bismuth telluride, the positive electrode material used in the aqueous manganese ion energy storage device of this invention.

[0036] Figure 6 The cyclic voltammetry (CV) curves of the aqueous manganese ion three-electrode energy storage device of the present invention at different scan rates are shown.

[0037] Figure 7 These are the rate performance test curves of the aqueous manganese ion three-electrode energy storage device of the present invention under different current densities;

[0038] Figure 8 The constant current charge-discharge curves (GCD) of the water-based manganese ion energy storage device of the present invention under different current densities are shown below.

[0039] Figure 9 The discharge curves of the water-based manganese ion energy storage device of the present invention after charging at a temperature difference of 20°C with different current densities are shown.

[0040] Figure 10 The data is a rate performance test curve of an aqueous manganese ion three-electrode energy storage device with a 1 mol / L manganese trifluoromethanesulfonate solution as the electrolyte, under different current densities.

[0041] Figure 11 The data is a rate performance test curve of an aqueous manganese ion three-electrode energy storage device with a 1 mol / L manganese chlorate solution as the electrolyte, under different current densities.

[0042] Figure 12 The data is a rate performance test curve of an aqueous manganese ion three-electrode energy storage device with perylene tetracarboxylic dianhydride as the positive electrode material, under different current densities. Detailed Implementation

[0043] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0044] Unless otherwise specified, all test materials and reagents used in the following examples are commercially available. Where specific techniques or conditions are not specified in the examples, they can be performed according to the techniques or conditions described in the literature or according to the product instructions.

[0045] It should also be noted that the manganese trifluoromethanesulfonate (purity ≥98%, product number: M914035) used in this invention was purchased from Shanghai Maclean Biochemical Technology Co., Ltd., and the manganese perchlorate (purity: Reagent) was also purchased from the same manufacturer. Grade (item number: M830894) was purchased from Shanghai Maclean Biochemical Technology Co., Ltd.; Polyvinylpyrrolidone (purity: average molecular weight 1,300,000, K88-96, item number: P110610) was purchased from Aladdin Biochemical Technology Co., Ltd.; Ethylene glycol (purity AR, i.e., 98%, item number: E103319) was purchased from Aladdin Biochemical Technology Co., Ltd.; Tellurium dioxide (purity ≥99.99%, item number: T103864) was purchased from Aladdin Biochemical Technology Co., Ltd.; Bismuth trichloride (purity: AR, item number: B801820) was purchased from Shanghai Maclean Biochemical Technology Co., Ltd.; Sodium hydroxide (tablets, purity AR (Shanghai test), National Drug Code: 10019764) was purchased from Sinopharm Chemical Reagent Co., Ltd.; Polyvinylidene fluoride (purity Kynar Flex) was purchased from Aladdin Biochemical Technology Co., Ltd. Item 2801 (item number: 10252) was purchased from Shanghai Aichun Biotechnology Co., Ltd.; acetylene black (purity AB, i.e., 99.9%, 50% compressed, item number: 039724.30) was purchased from Thermo Fisher Scientific Co., Ltd.; graphite paper (thickness 0.1 mm) was purchased from Beijing Jinglong Special Carbon Technology Co., Ltd.; anhydrous ethanol (purity 99.8%, item number: E111964) was purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.; and zinc foil (thickness 0.1 mm) was purchased from Shenzhen Kejing Zhida Technology Co., Ltd.

[0046] Example 1

[0047] (1) Electrolyte preparation: At room temperature, 1.775 g of manganese trifluoromethanesulfonate (Mn(OTF)2) was dissolved in 5 mL of deionized water and stirred at 900 rpm for 30 minutes to obtain a 1 mol / L manganese trifluoromethanesulfonate solution;

[0048] Dissolve 1.809 g of manganese perchlorate hexahydrate (Mn(ClO4)2·6H2O) in 5 mL of deionized water and stir at 900 rpm for 30 minutes to obtain a 1 mol / L manganese perchlorate solution.

[0049] Take 500 mL of the above manganese trifluoromethanesulfonate solution and 500 mL of the above manganese perchlorate solution, mix and stir at 800 rpm for 1 hour to obtain a mixed solution of 0.5 mol / L manganese trifluoromethanesulfonate and 0.5 mol / L manganese perchlorate, which is denoted as electrolyte.

[0050] (2) Preparation of titanium electrodes

[0051] Titanium foil measuring 1cm × 0.5cm was cut, ultrasonically washed multiple times with acetone, ethanol, and deionized water, and then dried to obtain a titanium electrode.

[0052] (3) Test

[0053] The solution was injected into a sealed capillary tube, and a laser wavelength of 532 nanometers was selected for testing. For example... Figure 2 The images shown are the Raman spectra of manganese trifluoromethanesulfonate solution, manganese perchlorate solution, and electrolyte, respectively. It can be seen that OTF... - sulfate ions (SO) in 3- The peak position is at 1030cm. -1 A slight red shift compared to the standard peak position indicates that the OTF - The solvation of manganese ions was altered. Using titanium electrodes as both positive and negative electrodes, with a 2cm gap between them, three solutions were used sequentially as electrolytes for testing. The conductivity was calculated using the formula σ = L / (R × A), where σ is the conductivity, L is the distance between the electrodes, R is the resistance, and A is the electrode area. Figure 3 The diagram shows the electrochemical impedance spectroscopy and calculated conductivity of manganese trifluoromethanesulfonate solution, manganese perchlorate solution, and electrolyte. Since the transverse intercept of the electrochemical impedance spectroscopy is the resistance, according to the calculation formula, it can be seen that the manganese trifluoromethanesulfonate solution has the highest conductivity, followed by the electrolyte, and the manganese perchlorate solution has the lowest conductivity. Therefore, the electrolyte has better conductivity.

[0054] The present invention discloses a method for preparing a thermoelectrically rechargeable aqueous manganese ion energy storage device, comprising:

[0055] (1) The preparation of the electrolyte is the same as in Example 1.

[0056] (2) Preparation of bismuth telluride electrode

[0057] Add 0.4 g of polyvinylpyrrolidone to 25 mL of ethylene glycol, mix, and stir at 1000 rpm for 8 hours until the solution becomes clear. Add 0.5 g of sodium hydroxide, 0.24 g of tellurium dioxide, and 0.315 g of bismuth trichloride, and stir at 2000 rpm for 4 hours until the solution becomes clear. Transfer the stirred liquid to a reaction vessel and perform a hydrothermal reaction at 180°C for 9 hours. Pour the reacted liquid into a vacuum filtration apparatus, wash the liquid three times with alcohol, and then wash it three times with deionized water. After filtration, remove the bismuth telluride and place it in a vacuum drying oven at 60°C for 1 hour to obtain bismuth telluride powder. Figure 4 The image shows the X-ray diffraction pattern of bismuth telluride. Figure 5 The image shown is an electron microscope scan of bismuth telluride. Figure 4 and Figure 5The successful synthesis of bismuth telluride, a topological insulating material, has been demonstrated.

[0058] Weigh 21 mg of bismuth telluride, 6 mg of acetylene black, and 3 mg of polyvinylidene fluoride using a balance. Pipette 500 ml of N-methylpyrrolidone (NMP, 99.9% purity, purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.). Place three 5 mm diameter beads (purchased from Jinrui New Materials Co., Ltd.) into a round container. Place the container on a homogenizer and homogenize at 2000 rpm for 1 hour to obtain a slurry. Select graphite paper with a thickness of 0.1 mm and cut a 1.2 cm diameter disc. Pipette 30 μL of the mixed slurry onto the cut circular graphite paper and dry to obtain the bismuth telluride electrode.

[0059] (3) Preparation of activated carbon electrode.

[0060] Weigh 0.1 g of polyvinylidene fluoride and 0.9 g of ultra-high capacity porous activated carbon (specific surface area of ​​2000 m² / g, particle size of 10 μm, purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.). Using a pipette, take 1.7 mL of N-methylpyrrolidone and place it along with 3 5 mm diameter beads into a round container. Place the container in a homogenizer and rotate it alternately at 1000 rpm and 2000 rpm for 30 minutes at each speed, repeating this process 3 times. Place the prepared slurry into a coating machine. After verifying the instrument is working correctly, place a 0.1 mm thick sheet of graphite paper inside, adjust the instrument, and after coating, heat at 60°C for 3 hours to obtain the activated carbon electrode.

[0061] (4) Test

[0062] A three-electrode energy storage system for manganese ions was constructed, using a bismuth telluride electrode as the working electrode, an activated carbon electrode as the counter electrode, a silver / silver chloride electrode as the reference electrode, and an electrolyte. The CV curves of the energy storage system using a mixed solution as the electrolyte at different scan rates are shown below. Figure 6 As shown, each CV curve exhibits a distinct redox peak, indicating a multi-step reversible manganese ion insertion / extraction process. The rate performance test curves of the energy storage device using a mixed solution as the electrolyte at different current densities are shown below. Figure 7 As shown, the energy storage device with a mixed electrolyte solution has a specific capacity of up to 491 mAh / g at a current density of 0.5 A / g. In addition, the manganese ion three-electrode energy storage device can still recover 88% of its initial capacity after 5 cycles at different current densities, demonstrating high reversible specific capacity and excellent cycle stability.

[0063] Example 3

[0064] Aquatic manganese ion energy storage

[0065] (1) The preparation of the electrolyte is the same as in Example 1.

[0066] (2) The preparation of the bismuth telluride electrode is the same as in Example 2.

[0067] (3) Preparation of zinc foil electrodes.

[0068] A 1 cm × 2 cm zinc foil was cut, ultrasonically washed multiple times with alcohol and water, and then dried to obtain the zinc foil negative electrode.

[0069] (4) Test

[0070] An aqueous manganese ion energy storage device was constructed using a bismuth telluride electrode as the positive electrode, a zinc foil electrode as the negative electrode, and a mixed solution as the electrolyte. The GCD curves of the assembled energy storage device at different current densities are shown below. Figure 8 As shown, the energy storage device exhibits a capacity as high as 400 mA / g at a current density of 0.5 A / g, demonstrating a high specific capacity. An aqueous manganese ion energy storage device, composed of a mixed solution as the electrolyte, had its zinc foil negative electrode maintained at room temperature (25°C) and its bismuth telluride positive electrode maintained at 45°C. After charging of the positive and negative electrodes at a temperature difference of 20°C, the heating source was removed, and the discharge curves at different current densities are shown below. Figure 9 As shown, after the positive and negative electrodes are charged at a temperature difference of 20°C, the manganese ion energy storage device has a specific capacity of 190 mA / g at a current density of 0.5 A / g. Figure 9 This invention demonstrates that the aqueous manganese ion energy storage device has excellent thermoelectric conversion capabilities.

[0071] Comparative Example 1

[0072] (1) The preparation of manganese trifluoromethanesulfonate solution is the same as in Example 1.

[0073] (2) The preparation of the bismuth telluride electrode is the same as in Example 2.

[0074] (3) The preparation of activated carbon electrode is the same as in Example 2.

[0075] (4) Test

[0076] A three-electrode aqueous manganese ion energy storage device was constructed using a bismuth telluride electrode as the working electrode, an activated carbon electrode as the counter electrode, a silver / silver chloride electrode as the reference electrode, and manganese trifluoromethanesulfonate solution as the electrolyte. The rate performance test curves of the assembled energy storage device at different current densities are shown below. Figure 10 As shown, although the specific capacity of the bismuth telluride electrode is 630 mAh / g at a current density of 0.5 A / g, the capacity of the energy storage device is only 36% of the initial capacity after 5 cycles at different current densities. Compared with Example 2, it can be proved that a single manganese trifluoromethanesulfonate solution is not suitable as an electrolyte for manganese ion energy storage devices.

[0077] Comparative Example 2

[0078] (1) The preparation of manganese perchlorate solution is the same as in Example 1.

[0079] (2) The preparation of the bismuth telluride electrode is the same as in Example 2.

[0080] (3) The preparation of activated carbon electrode is the same as in Example 2.

[0081] (4) Test

[0082] A three-electrode aqueous manganese ion energy storage device was constructed using a bismuth telluride electrode as the working electrode, an activated carbon electrode as the counter electrode, a silver / silver chloride electrode as the reference electrode, and a manganese perchlorate solution as the electrolyte. The rate performance test curves of the assembled energy storage device at different current densities are shown below. Figure 11 As shown, although the energy storage device recovers 71% of its initial capacity after 5 cycles at different current densities, compared with Comparative Example 1, it can be demonstrated that bismuth telluride is more stable in manganese perchlorate solution than in manganese trifluoromethanesulfonate solution. However, at a current density of 0.5 A / g, the specific capacity of the bismuth telluride electrode is only 345 mAh / g. Compared with Example 2, it can be demonstrated that manganese perchlorate solution alone is not suitable as an electrolyte for manganese ion energy storage devices.

[0083] Comparative Example 3

[0084] (1) The preparation of electrolyte is the same as in Example 1.

[0085] (2) Preparation of perylene tetracarboxylic dianhydride (PTCDA) electrode.

[0086] Weigh 20 mg of perylene dianhydride (98% purity, purchased from Shanghai Maclean Biochemical Technology Co., Ltd.), 2.5 mg of acetylene black, and 2.5 mg of polyvinylidene fluoride using a balance. Pipette 500 ml of NMP and place three 5 mm diameter beads into a round dish. Place the dish on a homogenizer and homogenize at 2000 rpm for 1 hour to obtain a slurry. Cut a 1.2 cm diameter circle from 0.1 mm thick graphite paper. Pipette 24 μL of the mixed slurry onto the cut circular graphite paper and dry to obtain the perylene dianhydride electrode.

[0087] (3) The preparation of activated carbon electrode is the same as in Example 2.

[0088] (4) Test

[0089] A three-electrode aqueous manganese ion energy storage device was constructed using a PTCDA electrode as the working electrode, an activated carbon electrode as the counter electrode, a silver / silver chloride electrode as the reference electrode, and a mixed solution as the electrolyte. The rate performance test curves of the assembled energy storage device at different current densities are shown below. Figure 12As shown, although the energy storage device can recover to 70% of its initial capacity after 5 cycles at different current densities, compared with Example 2, it can be demonstrated that bismuth telluride has a higher specific capacity in the mixed solution than PTCDA, and bismuth telluride is more suitable as the positive electrode material for aqueous manganese ion energy storage devices.

[0090] This invention illustrates the product and detailed preparation method of the present invention through the above embodiments. However, the present invention is not limited to the above-described product and detailed preparation method, that is, it does not mean that the present invention must rely on the above-described product and detailed preparation method to be implemented. Those skilled in the art should understand that any improvements to the present invention, equivalent substitutions of the raw materials of the product of the present invention, addition of excipients, and selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

[0091] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific details of the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention. These simple modifications all fall within the protection scope of the present invention.

[0092] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not describe the various possible combinations separately.

[0093] Furthermore, various different embodiments of the present invention can be combined in any way, as long as they do not violate the spirit of the present invention, they should also be regarded as the content disclosed by the present invention.

Claims

1. A method for preparing a thermoelectrically rechargeable aqueous manganese ion energy storage device, characterized in that, step include: S1. An electrolyte is obtained by mixing manganese trifluoromethanesulfonate solution and manganese perchlorate solution. S2. Bismuth telluride, acetylene black and polyvinylidene fluoride are mixed to prepare a slurry. The slurry is coated on a cut graphite paper and dried to obtain a bismuth telluride cathode. S3. The metal foil is ultrasonically and dried to obtain the negative electrode; S4. The energy storage device is obtained by assembling the electrolyte, positive electrode and negative electrode. Wherein, the manganese trifluoromethanesulfonate solution is an aqueous solution of manganese trifluoromethanesulfonate with a concentration of 1-2 mol / L; the manganese perchlorate solution is an aqueous solution of manganese perchlorate with a concentration of 1-2 mol / L; the volume ratio of the manganese trifluoromethanesulfonate solution to the manganese perchlorate solution is 3-7:3-7; and the weight ratio of bismuth telluride, acetylene black and polyvinylidene fluoride is 10.5-21:3-6:1.5-3.

2. The method for preparing a thermoelectrically rechargeable aqueous manganese ion energy storage device according to claim 1, characterized in that, The drying temperature in S2 is 50-60℃, and the drying time is 40-60 min.

3. The method for preparing a thermoelectrically rechargeable aqueous manganese ion energy storage device according to claim 1, characterized in that, The method for preparing bismuth telluride includes: adding polyvinylpyrrolidone to ethylene glycol, mixing and stirring until the solution is transparent, adding sodium hydroxide, tellurium dioxide and bismuth trichloride, and stirring until the solution is transparent; transferring to a reaction vessel for hydrothermal reaction, and cleaning and drying after the reaction is completed to obtain the bismuth telluride.

4. The method for preparing a thermoelectrically rechargeable aqueous manganese ion energy storage device according to claim 3, characterized in that, The ratio of polyvinylpyrrolidone, ethylene glycol, sodium hydroxide, tellurium dioxide, and bismuth trichloride is 0.4-0.8g: 25-50mL: 0.5-1.0g: 0.24-0.48g: 0.315-0.63g.

5. The method for preparing a thermoelectrically rechargeable aqueous manganese ion energy storage device according to claim 3, characterized in that, The hydrothermal reaction is carried out at a temperature of 180-220℃ for 9-12 hours.

6. The method for preparing a thermoelectrically rechargeable aqueous manganese ion energy storage device according to claim 3, characterized in that, The cleaning process involves multiple washes using anhydrous ethanol and deionized water, respectively.

7. The method for preparing a thermoelectrically rechargeable aqueous manganese ion energy storage device according to claim 1, characterized in that, The metal foil is a zinc metal foil, and the ultrasound in S3 is performed by sonication in anhydrous ethanol for 10-30 minutes.

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