Design and application of pure light rechargeable battery

Abstract

The invention belongs to the field of electrochemical energy storage, and discloses design and application of an integrated pure light rechargeable battery. The pure light rechargeable battery comprises a positive electrode and a negative electrode, the active material of the positive electrode is silver halide, and the active material of the negative electrode is cuprous halide. According to the invention, an integrated pure light rechargeable battery system is constructed, and a silver halide photoelectrode with an efficient photoelectric conversion characteristic is organically integrated with a rechargeable energy storage assembly. By means of the innovative design, efficient conversion and storage from light energy to electric energy and then to chemical energy are achieved, pure light charging of the two-electrode system in the true sense is achieved, and a new direction is opened up for developing a novel efficient and convenient energy storage device.

Description

Technical Field

[0001] The present invention belongs to the field of electrochemical energy storage, and in particular relates to the design and application of an integrated pure light-rechargeable battery. Background Art

[0002] In recent years, with the development of power grid systems, artificial intelligence devices, and wearable self-powered small electronic products, integrated-PRBs (IPRBs) have attracted widespread attention from researchers at home and abroad. This advanced IPRBs system greatly improves the theoretical efficiency of solar energy conversion and storage by directly integrating semiconductor photoelectrodes with photoelectric conversion functions into rechargeable energy storage devices. Despite this, there are still many challenges in the development of efficient and stable integrated-PRBs (IPRBs). Among them, the mismatch between the energy band position of the photoelectrode and the redox potential of the battery is an important reason for the low photoelectric conversion efficiency of the battery. Therefore, in most of the existing reported literature, the practical application of such IPRBs is limited to light-assisted charging, and it is impossible to achieve a true charging process relying solely on light sources.

[0003] Metal halides are a common type of photocatalyst because of their suitable energy band structure and good photoelectric response. In particular, silver halides (AgX X=Cl, Br, I) can generate a large number of photogenerated electron-hole pairs under light excitation, and have a high separation efficiency, and have been widely used in solar cells. However, how to use the excellent photoelectric properties of metal halides to design a bifunctional electrode to enable the battery to be charged only by light source is still a major problem. Summary of the invention

[0004] In order to overcome the above-mentioned shortcomings and deficiencies of the prior art, the primary purpose of the present invention is to provide a pure light-rechargeable battery that only relies on a light source to complete battery charging.

[0005] Another object of the present invention is to provide a method for preparing the above-mentioned pure light-rechargeable battery.

[0006] Another object of the present invention is to provide an application of the above-mentioned pure light-rechargeable battery.

[0007] The purpose of the present invention is achieved through the following solutions:

[0008] A pure light-chargeable battery comprises a positive electrode and a negative electrode, wherein the positive electrode active material is silver halide and the negative electrode active material is cuprous halide;

[0009] The silver halide is one of silver iodide, silver chloride and silver bromide, preferably AgI;

[0010] The cuprous halide is one of cuprous iodide, cuprous chloride and cuprous bromide, preferably CuI.

[0011] The pure light rechargeable battery also includes an electrolyte, wherein the electrolyte is one of potassium iodide-ethylene glycol solution, potassium iodide-ethanol solution, and potassium iodide-water solution, preferably potassium iodide-ethylene glycol solution; wherein the concentration of potassium iodide is 0.5-2M.

[0012] The pure light rechargeable battery also includes a diaphragm, wherein the diaphragm is one of a glass fiber diaphragm, a polypropylene membrane, and an anion exchange membrane, preferably a glass fiber diaphragm.

[0013] The pure light-chargeable battery is preferably a pure sunlight-chargeable battery.

[0014] A method for preparing a pure light-rechargeable battery comprises the following steps:

[0015] (1) silver halide powder, a conductive agent, a binder, and a solvent are mixed and ground to obtain a slurry, the slurry is coated on a current collector, and dried to obtain a photoelectric positive electrode of a pure photorechargeable battery;

[0016] (2) mixing cuprous halide powder material, a conductive agent, a binder, and a solvent, grinding to obtain a slurry, coating the slurry on a current collector, and drying to obtain the negative electrode of the pure light-chargeable battery;

[0017] (3) Assemble the positive electrode obtained in step (1), the negative electrode obtained in step (2), the electrolyte and the separator to obtain a pure light-chargeable battery.

[0018] The silver halide powder described in step (1) is preferably prepared by the following method: mixing a silver nitrate solution and a potassium halide solution (or a hydrogen halide solution), and stirring them uniformly to obtain a silver halide material; wherein the molar ratio of the silver nitrate to the potassium halide (or the hydrogen halide) is 1:1; stirring uniformly means stirring at room temperature for 0.5-1h;

[0019] The current collector described in step (1) is one of carbon cloth, carbon paper, and nickel foam, preferably carbon cloth.

[0020] The conductive agent described in step (1) is at least one of carbon black (CB), carbon nanotubes (CNTs), and graphene oxide (rGO); the binder described in step (1) is at least one of polyvinylidene fluoride (PVDF), polyvinyl alcohol, and polyvinyl ketone; the solvent described in step (1) is at least one of N-methylpyrrolidone and dimethyl sulfoxide.

[0021] The mass ratio of the silver halide powder, the conductive agent and the binder in step (1) is 6-8:2-1:2-1, preferably 8:1:1;

[0022] The loading amount of the active substance silver halide powder on the carbon cloth in step (1) is 1.1-1.5 mg cm-2 .

[0023] The cuprous halide powder described in step (2) is preferably prepared by the following method: mixing a copper nitrate solution and a potassium halide solution (or a hydrogen halide solution), and stirring them thoroughly to obtain a cuprous halide material; wherein the molar ratio of copper nitrate to potassium halide (or hydrogen halide) is 1:1; stirring thoroughly means stirring at room temperature for 0.5-1h;

[0024] The current collector described in step (2) is one of carbon cloth, carbon paper, and nickel foam, preferably carbon cloth.

[0025] The conductive agent described in step (2) is at least one of carbon black (CB), carbon nanotubes (CNTs), and graphene oxide (rGO); the binder described in step (2) is at least one of polyvinylidene fluoride (PVDF), polyvinyl alcohol, and polyvinyl ketone; the solvent described in step (2) is at least one of N-methylpyrrolidone and dimethyl sulfoxide.

[0026] The mass ratio of the cuprous halide powder, the conductive agent and the binder in step (2) is 6-8:2-1:2-1, preferably 8:1:1.

[0027] The loading amount of the active substance cuprous halide powder on the carbon cloth in step (1) is 1.3-1.7 mg cm -2 .

[0028] The drying in step (1) and step (2) is preferably vacuum drying, and the temperature of vacuum drying is 50-65°C.

[0029] The assembly described in step (3) is preferably performed in the following order: negative electrode shell → negative electrode → separator → positive electrode → perforated gasket → spring → positive electrode shell;

[0030] The positive electrode shell described in step (3) is preferably a positive electrode shell with holes sealed with an 8 mm glass sheet, which is specifically prepared by the following method: a 5 mm diameter hole is laser-punched in the positive electrode battery shell, UV glue is applied, and an 8 mm diameter glass sheet is attached. The positive electrode of the button battery is exposed to ultraviolet light and the glue is dried to form a closed environment.

[0031] The mechanism of the present invention is:

[0032] According to the theoretical analysis of photocatalytic thermodynamics, in the IPRBs system, only when the conduction band (CB) and valence band (VB) of the semiconductor photocatalyst completely cross the redox potential can the photoelectrode be used for photocharging and energy storage. However, since the redox potential of the metal anode is more negative than the CB of most semiconductor materials, in theory, IPRBs require the presence of an external voltage to realize the photocharging and energy storage process.

[0033] The present invention proposes to construct an AgI-CuI full battery system, which meets the kinetic requirements of charging only by light source. The active material of the negative electrode of the battery is CuI, and the following reactions mainly occur during the charging and discharging process: CuI+e - +Ag + →Ag x Cu 1-x I.

[0034] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0035] Traditional light-assisted batteries cannot be charged completely by light energy due to thermodynamic limitations. The present invention constructs an integrated pure light-chargeable battery system, which organically integrates silver halide photoelectrodes with efficient photoelectric conversion characteristics with rechargeable energy storage components. This innovative design realizes efficient conversion and storage from light energy to electrical energy and then to chemical energy, achieving true pure light charging of the two-electrode system, and opens up a new direction for the development of new, efficient and convenient energy storage devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 This is a scanning electron microscope image of AgI obtained in Example 1 of the present invention;

[0037] Figure 2 This is a scanning electron microscope image of CuI obtained in Example 1 of the present invention;

[0038] Figure 3 XRD patterns of AgI and CuI obtained in Example 1 of the present invention;

[0039] Figure 4 This is a CV comparison diagram of the battery in Example 1 of the present invention under light / no light conditions;

[0040] Figure 5 This is a long cycle performance diagram of the battery in Example 1 of the present invention under 1C current density light / dark conditions;

[0041] Figure 6 Schematic diagram of the change of current of the battery in embodiment 1 of the present invention during pure light charging.

[0042] Figure 7 This is a CV curve diagram of the battery in Example 2 of the present invention under light conditions;

[0043] Figure 8 This is a CV comparison diagram of the battery in Example 3 of the present invention under light / no light conditions;

[0044] Fig. 9 This is a long cycle performance diagram of the battery of Example 4 of the present invention under 1C current density lighting conditions. DETAILED DESCRIPTION

[0045] The present invention is further described in detail below in conjunction with the embodiments and drawings, but the embodiments of the present invention are not limited thereto. In addition, the technical features involved in each embodiment of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0046] If the specific conditions are not specified in the examples, the experiments were carried out under conventional conditions or conditions recommended by the manufacturer. If the manufacturers of the reagents or instruments are not specified, they are all conventional products that can be purchased commercially.

[0047] Example 1

[0048] Disperse 0.6g of silver nitrate in 60mL of deionized water and stir well. Take 0.67g of potassium iodide and disperse it in 60mL of deionized water and stir well. After adding the prepared silver nitrate solution drop by drop into the potassium iodide solution, stir at room temperature for 30 minutes, and centrifuge and dry to obtain the AgI powder active material. The active material, polyvinylidene fluoride and carbon black are ground in a mass ratio of 8:1:1 in N-methylpyrrolidone solvent to obtain a slurry, and the slurry is coated on carbon cloth and dried in a vacuum oven at 60°C to obtain the positive electrode material of the battery. Calculated by weighing, the active material loading is about 1.3mg / cm 2 .

[0049] Disperse 0.8g of copper nitrate in 60mL of deionized water and stir well. Take 0.82g of potassium iodide and disperse it in 60mL of deionized water and stir well. After adding the prepared silver nitrate solution drop by drop into the potassium iodide solution, stir at room temperature for 30 minutes, and centrifuge and dry to obtain CuI powder active material. Grind the active material with polyvinylidene fluoride and carbon black in a mass ratio of 8:1:1 in N-methylpyrrolidone solvent to obtain a slurry, and coat the slurry on carbon cloth, dry it in a vacuum oven at 60°C to obtain the negative electrode material of the battery. Calculated by weighing, the active material loading is about 1.5mg / cm 2 .

[0050] The positive battery shell is laser-punched with a 5mm diameter hole, UV glue is applied, and a 8mm diameter glass sheet is attached. Irradiate under UV light, and the glue dries to form a closed environment for the positive electrode of the button battery. The battery assembly order is negative electrode shell → CuI negative electrode → glass fiber diaphragm → AgI photoelectric positive electrode → perforated gasket → spring → 8mm glass sheet sealed perforated positive electrode shell; the electrolyte is 1M potassium iodide-ethylene glycol solution, and the assembly of CR2032 button batteries is completed in a glove box filled with argon.

[0051] Figure 1 and Figure 2 SEM images of AgI and CuI coated carbon cloth respectively. Figure 3XRD patterns of AgI and CuI coated carbon cloth, confirming the successful synthesis of the two materials. Figure 4 and Figure 5 The battery is exposed to light (xenon lamp ~ 100mW cm -2 ) / Electrochemical tests conducted under dark conditions clearly show that the introduction of light sources not only increases the area of ​​the battery's CV curve, but also in the 1C long cycle test, the introduction of xenon light sources not only increases the battery capacity to 62mA hg -1 , and maintain stability for 250 laps. Figure 6 The discharge process of the battery in the dark and pure light (xenon lamp ~100mW cm -2 ) The change of current during charging, where the positive and negative signs represent the direction of the current. It can be clearly seen that the battery can complete the charging process with only light source, proving that the battery is a battery system that can be charged purely by light.

[0052] Example 2

[0053] Disperse 0.6g of silver nitrate in 60mL of deionized water and stir well. Take 0.67g of potassium iodide and disperse it in 60mL of deionized water and stir well. After adding the prepared silver nitrate solution drop by drop into the potassium iodide solution, stir at room temperature for 30 minutes, and centrifuge and dry to obtain the AgI powder active material. The active material, polyvinylidene fluoride and carbon black are ground in a mass ratio of 8:1:1 in N-methylpyrrolidone solvent to obtain a slurry, and the slurry is coated on carbon cloth and dried in a vacuum oven at 60°C to obtain the positive electrode material of the battery. Calculated by weighing, the active material loading is about 1.3mg / cm 2 .

[0054] Disperse 0.8g of copper nitrate in 60mL of deionized water and stir well. Take 0.82g of potassium iodide and disperse it in 60mL of deionized water and stir well. After adding the prepared silver nitrate solution drop by drop into the potassium iodide solution, stir at room temperature for 30 minutes, and centrifuge and dry to obtain CuI powder active material. Grind the active material with polyvinylidene fluoride and carbon black in a mass ratio of 8:1:1 in N-methylpyrrolidone solvent to obtain a slurry, and coat the slurry on carbon cloth, dry it in a vacuum oven at 60°C to obtain the negative electrode material of the battery. Calculated by weighing, the active material loading is about 1.5mg / cm 2 .

[0055] Laser punch a 5mm diameter hole in the positive battery shell, apply UV glue, and stick an 8mm diameter glass sheet. Irradiate under UV light, and the glue will dry to form a sealed environment for the button battery. The battery assembly order is negative electrode shell → CuI negative electrode → glass fiber diaphragm → AgI photoelectric positive electrode → perforated gasket → shrapnel

[0056] →The positive electrode shell with holes is sealed with an 8mm glass sheet; the electrolyte is a 1M potassium iodide aqueous solution, and the assembly of the CR2032 button battery is completed in a glove box filled with argon.

[0057] Figure 7 The battery is under light conditions (xenon lamp ~ 100mW cm -2 ) under CV curve test, the introduction of light source causes obvious symmetrical redox peaks to appear in the CV curve of the battery, indicating that the charging and discharging process of the battery is a reversible process.

[0058] Example 3

[0059] Disperse 0.6g of silver nitrate in 60mL of deionized water and stir well. Take 0.67g of potassium iodide and disperse it in 60mL of deionized water and stir well. After adding the prepared silver nitrate solution drop by drop into the potassium iodide solution, stir at room temperature for 30 minutes, and centrifuge and dry to obtain the AgI powder active material. The active material, polyvinylidene fluoride and carbon black are ground in a mass ratio of 8:1:1 in N-methylpyrrolidone solvent to obtain a slurry, and the slurry is coated on carbon cloth and dried in a vacuum oven at 60°C to obtain the positive electrode material of the battery. Calculated by weighing, the active material loading is about 1.3mg / cm 2 .

[0060] Disperse 0.8g of copper nitrate in 60mL of deionized water and stir well. Take 0.82g of potassium iodide and disperse it in 60mL of deionized water and stir well. After adding the prepared silver nitrate solution drop by drop into the potassium iodide solution, stir at room temperature for 30 minutes, and centrifuge and dry to obtain CuI powder active material. Grind the active material with polyvinylidene fluoride and carbon black in a mass ratio of 8:1:1 in N-methylpyrrolidone solvent to obtain a slurry, and coat the slurry on carbon cloth, dry it in a vacuum oven at 60°C to obtain the negative electrode material of the battery. Calculated by weighing, the active material loading is about 1.5mg / cm 2 .

[0061] A 5mm diameter hole was laser-punched in the positive battery shell, UV glue was applied, and a 8mm diameter glass sheet was attached. The button battery was exposed to UV light and the glue was dried to form a closed environment. The battery assembly order was negative electrode shell → CuI negative electrode → anion exchange membrane (Fumasep FAA-3-50) → AgI photoelectric positive electrode → perforated gasket → spring → 8mm glass sheet sealed perforated positive electrode shell; the electrolyte was 1M potassium iodide-ethylene glycol solution, and the assembly of CR2032 button batteries was completed in a glove box filled with argon.

[0062] Figure 8 The battery is exposed to light (xenon lamp ~ 100mW cm -2) / From the electrochemical test carried out under dark conditions, it can be clearly seen that the introduction of light source increases the area of ​​the battery's CV curve.

[0063] Example 4

[0064] Disperse 0.6g of silver nitrate in 60mL of deionized water and stir well. After adding the prepared silver nitrate solution drop by drop into the 1M hydrochloric acid solution, stir at room temperature for 30 minutes, and centrifuge to obtain AgCl powder active material. Grind the active material with polyvinylidene fluoride and carbon black in a mass ratio of 8:1:1 in N-methylpyrrolidone solvent to obtain a slurry, and coat the slurry on carbon cloth and dry it in a vacuum oven at 60°C to obtain the positive electrode material of the battery. Calculated by weighing, the active material loading is approximately 1.5mg / cm 2 .

[0065] Disperse 0.8g of copper nitrate in 60mL of deionized water and stir well. After adding the prepared silver nitrate solution drop by drop into the 1M hydrochloric acid solution, stir at room temperature for 30 minutes, and centrifuge to obtain the CuCl powder active material. Grind the active material with polyvinylidene fluoride and carbon black in a mass ratio of 8:1:1 in N-methylpyrrolidone solvent to obtain a slurry, and coat the slurry on carbon cloth and dry it in a vacuum oven at 60°C to obtain the negative electrode material of the battery. Calculated by weighing, the active material loading is approximately 1.4mg / cm 2 .

[0066] A 5mm diameter hole was laser-punched in the positive battery shell, UV glue was applied, and a 8mm diameter glass sheet was attached. The button battery was exposed to UV light and the glue dried to form a closed environment. The battery assembly order was negative electrode shell → CuCl negative electrode → glass fiber diaphragm → AgCl photoelectric positive electrode → perforated gasket → spring → 8mm glass sheet sealed positive electrode shell with holes; the electrolyte was 1M potassium chloride-ethanol solution, and the assembly of CR2032 button batteries was completed in a glove box filled with argon.

[0067] Fig. 9 AgCl-CuCl battery under 1C current density illumination conditions (xenon lamp ~100mW cm -2 ) under long cycle test, the introduction of xenon lamp light source enables the battery to maintain stability for 200 cycles.

[0068] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention.

Claims

1. A pure light-chargeable battery, comprising a positive electrode and a negative electrode, characterized in that: The positive electrode active material is silver halide, and the negative electrode active material is cuprous halide.

2. The pure light rechargeable battery according to claim 1, characterized in that: The silver halide is one of silver iodide, silver chloride and silver bromide, preferably AgI; The cuprous halide is one of cuprous iodide, cuprous chloride and cuprous bromide, preferably CuI.

3. The pure light rechargeable battery according to claim 1, characterized in that: The pure light rechargeable battery also includes an electrolyte, wherein the electrolyte is one of potassium iodide-ethylene glycol solution, potassium iodide-ethanol solution, and potassium iodide-water solution, wherein the concentration of potassium iodide is 0.5-2M.

4. The pure light rechargeable battery according to claim 1, characterized in that: The pure light rechargeable battery also includes a diaphragm, wherein the diaphragm is one of a glass fiber diaphragm, a polypropylene membrane, and an anion exchange membrane.

5. The pure light rechargeable battery according to claim 1, characterized in that: The pure light-chargeable battery is a pure sunlight-chargeable battery.

6. A method for preparing a pure light-rechargeable battery according to any one of claims 1 to 5, characterized in that The following steps are involved: (1) silver halide powder, a conductive agent, a binder, and a solvent are mixed and ground to obtain a slurry, the slurry is coated on a current collector, and dried to obtain a photoelectric positive electrode of a pure photorechargeable battery; (2) mixing cuprous halide powder material, a conductive agent, a binder, and a solvent, grinding to obtain a slurry, coating the slurry on a current collector, and drying to obtain the negative electrode of the pure light-chargeable battery; (3) Assemble the positive electrode obtained in step (1), the negative electrode obtained in step (2), the electrolyte and the separator to obtain a pure light-chargeable battery.

7. The method for preparing a pure light-rechargeable battery according to claim 6, characterized in that: The silver halide powder described in step (1) is prepared by the following method: mixing a silver nitrate solution and a potassium halide solution or a hydrogen halide solution, and stirring them uniformly to obtain a silver halide material; wherein the molar ratio of the silver nitrate to the potassium halide or the hydrogen halide is 1:1; stirring uniformly means stirring at room temperature for 0.5-1h; The cuprous halide powder described in step (2) is prepared by the following method: mixing a copper nitrate solution and a potassium halide solution, and stirring them evenly to obtain a cuprous halide material; wherein the molar ratio of the copper nitrate to the potassium halide or the hydrogen halide is 1:1; stirring evenly means stirring at room temperature for 0.5-1h.

8. The method for preparing a pure light-rechargeable battery according to claim 6, characterized in that: The current collector in step (1) is one of carbon cloth, carbon paper and nickel foam; The conductive agent described in step (1) is at least one of carbon black, carbon nanotubes, and graphene oxide; the binder described in step (1) is at least one of polyvinylidene fluoride, polyvinyl alcohol, and polyvinyl ketone; the solvent described in step (1) is at least one of N-methylpyrrolidone and dimethyl sulfoxide; The mass ratio of the silver halide powder, the conductive agent and the binder in step (1) is 6-8:2-1:2-1.

9. The method for preparing a pure light-rechargeable battery according to claim 6, characterized in that: The current collector in step (2) is one of carbon cloth, carbon paper and nickel foam; The conductive agent described in step (2) is at least one of carbon black, carbon nanotubes, and graphene oxide; the binder described in step (2) is at least one of polyvinylidene fluoride, polyvinyl alcohol, and polyvinyl ketone; the solvent described in step (2) is at least one of N-methylpyrrolidone and dimethyl sulfoxide; The mass ratio of the cuprous halide powder, the conductive agent and the binder described in step (2) is 6-8:2-1:2-1.

10. The method for preparing a pure light-rechargeable battery according to claim 6, characterized in that: The loading amount of the active substance silver halide powder on the carbon cloth in step (1) is 1.1-1.5 mg cm -2 ; The loading amount of the active substance cuprous halide powder on the carbon cloth in step (1) is 1.3-1.7 mg cm -2 .

Images