Electrochemical system and method for recycling batteries

Abstract

The application discloses an electrochemical system and method for recycling batteries, the electrochemical system comprises a positive electrode cavity, a negative electrode cavity, a diaphragm and a light excitation device; the positive electrode cavity is provided with an acidic liquid; the negative electrode cavity is provided with an acidic liquid. The method comprises the following steps: (i) providing an electrochemical system, the electrochemical system comprises a positive electrode cavity, a negative electrode cavity, a diaphragm and a light excitation device; the positive electrode cavity is provided with an acidic liquid; the negative electrode cavity is provided with an acidic liquid; (ii) placing a positive electrode of a battery to be treated into the acidic liquid in the positive electrode cavity; (iii) placing a negative electrode of a battery to be treated into the acidic liquid in the negative electrode cavity; (iv) connecting the positive electrode of the battery to be treated and the negative electrode of the battery to be treated; (v) irradiating the positive electrode with light emitted by the light excitation device. The application not only can realize the recycling of resources, but also can do work outside, and the energy consumption is lower.

Description

Technical Field

[0001] This invention relates to the field of solid waste recycling and resource utilization technology, specifically to an electrochemical system and method for recycling batteries. Background Technology

[0002] A battery is a device that converts chemical energy into electrical energy. It contains an electrolyte solution and metal electrodes to generate an electric current. It is a cup, tank, or other container or a portion of a composite container. It has positive and negative electrodes. With technological advancements, the term "battery" now generally refers to any small device capable of generating electrical energy.

[0003] For example, lithium-ion batteries are a widely used clean energy source. As society's energy structure accelerates its shift towards green and sustainable practices, the new energy vehicle industry is booming, leading to a corresponding increase in the production and retirement of lithium-ion batteries. In 2021, global lithium-ion battery shipments reached 562.4 GWh, representing a market share of 59.4%. It is projected that by 2030, approximately 11 million tons of retired lithium-ion batteries will be generated. Retired lithium-ion batteries contain large amounts of heavy metals (Co, Ni, Mn) and toxic electrolytes, which, if not properly disposed of, can cause serious environmental pollution and safety problems. Furthermore, the positive electrode active material of lithium-ion batteries contains lithium and cobalt. Therefore, recycling retired lithium-ion batteries can achieve resource recycling and effectively protect the environment.

[0004] Typically, the positive electrode active materials of lithium-ion batteries are mainly LiCoO2 and LiNi. x Co y Mn z O2 (where x+y+z=1) and LiMn2O4, etc., the positive electrode current collector is aluminum foil, the negative electrode active material is graphite, and the current collector is copper foil. Currently, traditional methods for recycling retired lithium-ion batteries mainly include wet recycling, dry recycling, and biological recycling. Among them, hydrometallurgical lithium extraction is widely used due to its advantages of high product purity, low energy consumption, and minimal environmental pollution. Traditional hydrometallurgy includes four steps: pretreatment, leaching, separation and recycling, and reuse. Pretreatment mainly involves a series of operations such as dismantling, crushing, pulverizing, screening, filtering, sorting, magnetic separation, primary grinding, sorting, and secondary grinding of retired batteries. Leaching mostly involves dissolving valuable elements in the batteries under the action of acids or alkalis and reducing agents, or recovering all valuable metals in the positive electrode active material through electrochemical reduction, or selectively recovering metallic lithium through electrochemical oxidation, thereby achieving green and efficient leaching.

[0005] However, traditional electrochemical reduction methods for recycling retired batteries can only recover the cathode material, and an external voltage is required during the leaching process. Furthermore, current battery-like structures for recycling retired batteries suffer from slow leaching kinetics and poor leaching efficiency. Other types of batteries typically contain elements such as cobalt, nickel, and manganese. Similarly, recycling these batteries also suffers from slow leaching kinetics and poor leaching efficiency. Summary of the Invention

[0006] To address the problems existing in the prior art, in a first aspect, the present invention aims to provide an electrochemical system for recycling batteries. In a second aspect, the present invention aims to provide the use of the electrochemical system for recycling batteries. In a third aspect, the present invention aims to provide a method for recycling batteries. Compared with traditional electrochemical reduction methods for recycling the positive electrode of retired batteries, the present invention is more economical, has faster leaching kinetics, better leaching effect, and lower energy consumption. Ultimately, the present invention can achieve a highly efficient and energy-saving battery-like structure, and simultaneously recover valuable metals (such as lithium, cobalt, nickel, manganese, etc.) from the positive electrode of retired batteries, as well as copper foil from the negative electrode.

[0007] The present invention adopts the following technical solution:

[0008] In a first aspect, this application provides an electrochemical system for recycling batteries, the electrochemical system comprising a positive electrode cavity, a negative electrode cavity, a separator, and a photoexcitation device;

[0009] An acidic liquid is provided in the positive electrode cavity;

[0010] An acidic liquid is placed in the negative electrode cavity.

[0011] Battery recycling (e.g., lithium-ion batteries) is achieved by employing a battery-like structure. The positive electrode material is used as the positive electrode of the primary cell, and the negative electrode material is used as the negative electrode. An acidic liquid is added to the two electrode system, and both the positive and negative electrodes are simultaneously recovered under light excitation at a specific wavelength. The described battery-like structure uses a separator to separate the positive and negative electrode cavities, thus separating copper ions (potentially monovalent and divalent copper) and valuable metals dissolved in the acidic liquid.

[0012] For illustrative purposes and not for limitation, in some implementations, Figure 1 A schematic diagram of the electrochemical system of the present invention is shown, wherein reference numeral 1 represents the positive electrode, 2 represents the negative electrode, 3 represents the positive electrode cavity, 4 represents the negative electrode cavity, 5 represents the diaphragm, and 6 represents the photoexcitation device.

[0013] In conjunction with the first aspect, and not wishing to be bound by theory, the electrochemical system includes one or more positive electrode cavities.

[0014] In conjunction with the first aspect, and not wishing to be bound by theory, the electrochemical system includes one or more negative electrode cavities.

[0015] In conjunction with the first aspect, and not wishing to be bound by theory, the electrochemical system includes one or more membranes.

[0016] The term “multiple” as used in this article includes two, three, four or more, etc.

[0017] In conjunction with the first aspect, in some feasible embodiments, the acidic liquid in the positive electrode cavity includes an inorganic acid solution and / or an organic acid solution. Alternatively, the acidic liquid in the positive electrode cavity is an inorganic acid solution and / or an organic acid solution.

[0018] In conjunction with the first aspect, in some feasible embodiments, the acidic liquid in the negative electrode cavity includes an inorganic acid solution and / or an organic acid solution. Alternatively, the acidic liquid in the negative electrode cavity is an inorganic acid solution and / or an organic acid solution.

[0019] Not wanting to be bound by theory, acidic liquids can provide hydrogen ions, which can bind oxygen in transition metal oxides and help copper dissolve into the solution.

[0020] In conjunction with the first aspect, in some feasible embodiments, the acidic liquid in the positive electrode cavity comprises an inorganic acid solution, which includes at least one selected from hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, perchloric acid, hydrobromic acid, hydroiodic acid, boric acid, and carbonic acid; or, the inorganic acid solution is composed of at least one selected from hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, perchloric acid, hydrobromic acid, hydroiodic acid, boric acid, and carbonic acid. Alternatively, in some feasible embodiments, the acidic liquid in the positive electrode cavity comprises an inorganic acid solution, which includes at least one selected from hydrochloric acid, sulfuric acid, nitric acid, and phosphoric acid; or, the inorganic acid solution is composed of at least one selected from hydrochloric acid, sulfuric acid, nitric acid, and phosphoric acid.

[0021] In conjunction with the first aspect, in some feasible embodiments, the acidic liquid in the negative electrode cavity comprises an inorganic acid solution, which includes at least one selected from hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, perchloric acid, hydrobromic acid, hydroiodic acid, boric acid, and carbonic acid; or, the inorganic acid solution is composed of at least one selected from hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, perchloric acid, hydrobromic acid, hydroiodic acid, boric acid, and carbonic acid. Alternatively, in some feasible embodiments, the acidic liquid in the negative electrode cavity comprises an inorganic acid solution, which includes at least one selected from hydrochloric acid, sulfuric acid, nitric acid, and phosphoric acid; or, the inorganic acid solution is composed of at least one selected from hydrochloric acid, sulfuric acid, nitric acid, and phosphoric acid.

[0022] In conjunction with the first aspect, in some feasible embodiments, the acidic liquid in the positive electrode cavity comprises an organic acid solution, the organic acid solution comprising or consisting of at least one of the following: formic acid, acetic acid, propionic acid, butyric acid, octanoic acid, adipic acid, oxalic acid, malonic acid, succinic acid, maleic acid, tartaric acid, benzoic acid, phenylacetic acid, phthalic acid, terephthalic acid, valeric acid, hexanoic acid, decanoic acid, stearic acid, palmitic acid, acrylic acid, ascorbic acid, and malic acid.

[0023] In conjunction with the first aspect, in some feasible embodiments, the acidic liquid in the negative electrode cavity comprises an organic acid solution, the organic acid solution comprising or consisting of at least one of the following: formic acid, acetic acid, propionic acid, butyric acid, octanoic acid, adipic acid, oxalic acid, malonic acid, succinic acid, maleic acid, tartaric acid, benzoic acid, phenylacetic acid, phthalic acid, terephthalic acid, valeric acid, hexanoic acid, decanoic acid, stearic acid, palmitic acid, acrylic acid, ascorbic acid, and malic acid.

[0024] In conjunction with the first aspect, in some feasible implementations, the concentration of the acidic liquid in the positive electrode cavity is from 0.01 mol / L to 10 mol / L, for example, from 0.01 mol / L to 5 mol / L, for example, from 0.1 mol / L to 5 mol / L, for example, from 0.5 mol / L to 5 mol / L, for example, 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 mol / L, etc., but is not limited to the listed values; other unlisted values ​​or ranges within this range are also applicable.

[0025] In conjunction with the first aspect, in some feasible implementations, the concentration of the acidic liquid in the negative electrode cavity is 0.01 mol / L to 10 mol / L, for example 0.01 mol / L to 5 mol / L, for example 0.1 mol / L to 5 mol / L, for example 0.5 mol / L to 5 mol / L, for example 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 mol / L, etc., but is not limited to the listed values; other unlisted values ​​or ranges within this range are also applicable.

[0026] In some feasible embodiments, the inorganic acid is hydrochloric acid, and the concentration of the hydrochloric acid is from 0.5 mol / L to 2 mol / L. In some feasible embodiments, the inorganic acid is sulfuric acid, and the concentration of the sulfuric acid is from 0.1 mol / L to 5 mol / L. In some feasible embodiments, the inorganic acid is phosphoric acid, and the concentration of the phosphoric acid is from 0.5 mol / L to 2 mol / L.

[0027] In some preferred embodiments, the inorganic acid is hydrochloric acid and / or sulfuric acid, with hydrochloric acid effectively increasing the output voltage; while sulfuric acid has the lowest global warming potential (GWP) and human toxicity potential (HTP) as determined by life cycle assessment.

[0028] In some feasible implementations, without being bound by theory, the copper foil in the current collector of the negative electrode material in the galvanic cell constituted by the electrochemical system of this application loses two electrons and is oxidized to Cu. 2+ Upon entering the solution, electrons travel through the external circuit to the positive electrode, reducing the high-valence transition metal in the positive electrode to +2 valence before entering the solution. The final recovered products are: valuable elements dissolved in the positive electrode cavity (e.g., Li, Co, Ni, Mn), and Cu in the negative electrode cavity. 2+ This allows for the recycling and efficient recovery of resources through a series of subsequent recycling processes.

[0029] For illustrative purposes, the LiCoO2-HCl system is used as an example, where the electrolyte is hydrochloric acid, the positive electrode active material is LiCoO2, and the negative electrode current collector is copper foil. The reaction equation for the galvanic cell is:

[0030]

[0031] Specific leaching process mechanism:

[0032] Positive electrode: 2LiCoO2 + 8H + +2e - =2Co 2+ +2Li + +4H2O

[0033] positive electrode:

[0034] Negative electrode: Cu-e - =Cu +

[0035] Negative electrode: Cu + -e - =Cu 2+

[0036] negative electrode:

[0037] The reaction is exothermic and can proceed spontaneously at room temperature without the need for an external power source, thus saving energy. Furthermore, the theoretical open-circuit voltage of this galvanic cell is approximately 0.6V to 2.0V, allowing it to output energy.

[0038] The external environment mentioned in this article generally refers to room temperature conditions, such as 15°C to 35°C, but other conditions are not excluded. In actual operation, the temperature of the experimental conditions will be changed according to specific needs.

[0039] The normal temperature referred to in this article is usually between 15℃ and 35℃, but other conditions are not excluded.

[0040] The electrochemical system described in this paper can operate at ambient temperature. The reaction temperature in the recovery method described in this paper can be from -10°C to 80°C, for example -5°C to 70°C, for example 0°C to 60°C, for example 2°C to 55°C, etc.

[0041] In conjunction with the first aspect, in some feasible embodiments, the volume of the positive electrode cavity is at least 10 mL, for example at least 20 mL, for example at least 30 mL, for example at least 40 mL, for example at least 50 mL, for example at least 60 mL, for example at least 70 mL, for example at least 80 mL, for example at least 90 mL, for example at least 100 mL, for example at least 200 mL, for example at least 300 mL, for example at least 400 mL, for example at least 500 mL, for example at least 600 mL, for example at least 700 mL, for example at least 800 mL, for example at least 900 mL, for example at least 1000 mL, for example at least 20 ... Less than 3000mL, for example, at least 4000mL, for example, at least 5000mL, for example, at least 6000mL, for example, at least 7000mL, for example, at least 8000mL, for example, at least 9000mL, for example, at least 1.5L, for example, at least 2L, for example, at least 3L, for example, at least 4L, for example, at least 5L, for example, at least 6L, for example, at least 7L, for example, at least 8L, for example, at least 9L, for example, at least 10L, for example, at least 20L, for example, at least 30L, for example, at least 40L, for example, at least 50L, for example, at least 60L, for example, at least 70L, for example, at least 80L, for example, at least 90L, for example, at least 100L, etc.

[0042] In conjunction with the first aspect, in some feasible embodiments, the electrochemical system further includes a stirring device. The stirring device can stir the liquid in the positive electrode chamber and / or the negative electrode chamber separately. The stirring speed of the stirring device is at least 10 rpm / min, for example, at least 20 rpm / min, for example, at least 30 rpm / min, for example, at least 40 rpm / min, for example, at least 50 rpm / min, for example, at least 60 rpm / min, for example, at least 70 rpm / min, for example, at least 80 rpm / min, for example, at least 90 rpm / min, for example, at least 100 rpm / min, for example, at least 200 rpm / min, for example, at least 300 rpm / min, for example, at least 400 rpm / min, for example, at least 500 rpm / min. For example, the stirring speed can range from 100 rpm / min to 900 rpm / min.

[0043] In conjunction with the first aspect, the reaction time or reaction interval of the recovery (leaching) method is 30 min to 240 min, for example 60 to 120 min, such as 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240 min, etc., but is not limited to the listed values. Other unlisted values ​​or ranges within this range also apply.

[0044] In conjunction with the first aspect, in some feasible implementations, the wavelength of the light emitted by the photoexcitation device is ≤770nm.

[0045] In conjunction with the first aspect, in some feasible implementations, the wavelength of the light emitted by the photoexcitation device is ≤400nm.

[0046] In conjunction with the first aspect, in some feasible implementations, the wavelength of the light emitted by the photoexcitation device is from 10 nm to 400 nm.

[0047] In conjunction with the first aspect, in some feasible implementations, the wavelength of the light emitted by the photoexcitation device is between 320 nm and 400 nm.

[0048] In conjunction with the first aspect, in some feasible implementations, the wavelength of the light emitted by the photoexcitation device is between 280 nm and 320 nm.

[0049] In conjunction with the first aspect, in some feasible implementations, the wavelength of the light emitted by the photoexcitation device is between 190 nm and 280 nm.

[0050] In conjunction with the first aspect, in some feasible implementations, the wavelength of the light emitted by the photoexcitation device is between 100 nm and 190 nm.

[0051] In conjunction with the first aspect, in some feasible implementations, the wavelength of the light emitted by the photoexcitation device is from 10 nm to 100 nm.

[0052] In conjunction with the first aspect, in some feasible implementations, the wavelength of the light emitted by the photoexcitation device is, for example, 180nm, 185nm, 190nm, 195nm, 200nm, 205nm, 210nm, 215nm, 220nm, 225nm, 230nm, 235nm, 240nm, 245nm, 250nm, 254nm, 260nm, 265nm, 270nm, 275nm, 280nm, 285nm, 290nm. The range includes m, 295nm, 300nm, 305nm, 310nm, 315nm, 320nm, 325nm, 330nm, 335nm, 340nm, 345nm, 350nm, 355nm, 360nm, 365nm, 370nm, 375nm, 380nm, 385nm, 390nm, 395nm, 400nm, etc., but is not limited to the listed values. Other unlisted values ​​or ranges within this range also apply.

[0053] In conjunction with the first aspect, in some feasible implementations, the power of the photoexcitation device is ≥3W.

[0054] In conjunction with the first aspect, in some feasible implementations, the power of the photoexcitation device is ≥5W.

[0055] In conjunction with the first aspect, in some feasible implementations, the power of the photoexcitation device is ≥7W.

[0056] In conjunction with the first aspect, in some feasible implementations, the power of the photoexcitation device is ≥9W.

[0057] In conjunction with the first aspect, in some feasible implementations, the power of the photoexcitation device is ≥11W.

[0058] In conjunction with the first aspect, in some feasible implementations, the power of the photoexcitation device is ≥26W.

[0059] In conjunction with the first aspect, in some feasible implementations, the power of the photoexcitation device is ≥30W.

[0060] In conjunction with the first aspect, in some feasible implementations, the power of the photoexcitation device is ≥36W.

[0061] In conjunction with the first aspect, in some feasible implementations, the power of the photoexcitation device is ≥45W.

[0062] In conjunction with the first aspect, in some feasible implementations, the power of the photoexcitation device is ≥55W.

[0063] In conjunction with the first aspect, in some feasible implementations, the power of the photoexcitation device is ≥65W.

[0064] In conjunction with the first aspect, in some feasible implementations, the power of the photoexcitation device is ≥75W.

[0065] In conjunction with the first aspect, in some feasible implementations, the power of the photoexcitation device is ≥100W.

[0066] In conjunction with the first aspect, in some feasible implementations, the power of the photoexcitation device is ≥140W.

[0067] In conjunction with the first aspect, in some feasible implementations, the power of the photoexcitation device is ≥200W.

[0068] In conjunction with the first aspect, in some feasible embodiments, the acidic liquid in the positive electrode cavity is doped with nanobubbles, the diameter of which does not exceed 1000 nm, for example, not exceeding 900 nm, not exceeding 800 nm, not exceeding 700 nm, not exceeding 500 nm, not exceeding 400 nm, not exceeding 300 nm, not exceeding 200 nm, for example, 1 nm to 200 nm, for example, 10 nm to 200 nm, for example, 50 nm to 200 nm, for example, 60 nm to 190 nm, for example, 60 nm to 180 nm. 0nm, for example, 60nm to 170nm, for example, 60nm to 160nm, for example, 60nm to 150nm, for example, 60nm to 140nm, for example, 60nm to 130nm, for example, 60nm to 120nm, for example, 70nm to 120nm, for example, 80nm to 120nm, for example, 90nm to 120nm, for example, 80nm to 110nm, for example, approximately 120nm, for example, approximately 110nm, for example, approximately 100nm, for example, approximately 90nm, for example, approximately 80nm.

[0069] In conjunction with the first aspect, in some feasible embodiments, the acidic liquid in the negative electrode cavity is doped with nanobubbles, the diameter of which does not exceed 1000 nm, for example, not exceeding 900 nm, not exceeding 800 nm, not exceeding 700 nm, not exceeding 500 nm, not exceeding 400 nm, not exceeding 300 nm, not exceeding 200 nm, for example, 1 nm to 200 nm, for example, 10 nm to 200 nm, for example, 50 nm to 200 nm, for example, 60 nm to 190 nm, for example, 60 nm to 180 nm. 0nm, for example, 60nm to 170nm, for example, 60nm to 160nm, for example, 60nm to 150nm, for example, 60nm to 140nm, for example, 60nm to 130nm, for example, 60nm to 120nm, for example, 70nm to 120nm, for example, 80nm to 120nm, for example, 90nm to 120nm, for example, 80nm to 110nm, for example, approximately 120nm, for example, approximately 110nm, for example, approximately 100nm, for example, approximately 90nm, for example, approximately 80nm.

[0070] In conjunction with the first aspect, in some feasible implementations, the electrochemical system constitutes a galvanic cell system.

[0071] In conjunction with the first aspect, in some feasible implementations, the electrodes of the electrochemical system are a two-electrode system.

[0072] Unless otherwise stated, the term "two-electrode system" as used herein is as commonly understood by those skilled in the art, and in particular, "two-electrode system" in a galvanic cell.

[0073] In conjunction with the first aspect, in some feasible implementations, the electrochemical system does not include an external power source, that is, the electrochemical system can recycle battery materials without the need for an additional power supply device (e.g., a power source).

[0074] In conjunction with the first aspect, in some feasible embodiments, the electrochemical system includes conductive connecting components, which may be, for example, conductive wires, filaments, sheets, tubes, blocks, powders, etc.

[0075] In conjunction with the first aspect, in some feasible implementation schemes, the batteries to be recycled include at least one of lithium-ion batteries, sodium-ion batteries, potassium-ion batteries, lithium-sulfur batteries, sodium-sulfur batteries, and potassium-sulfur batteries.

[0076] In conjunction with the first aspect, in some feasible embodiments, a positive electrode cavity and a negative electrode cavity constitute a cavity combination, and the electrochemical system includes one or more such cavity combinations, with the positive electrode cavity and the negative electrode cavity separated by a membrane. The multiple combinations include two, three, four, or more combinations, etc. As an example, the electrochemical system includes a positive electrode cavity, a membrane, and a negative electrode cavity arranged sequentially. Optionally, the electrochemical system includes a negative electrode cavity, a membrane, and a positive electrode cavity arranged sequentially. As an example, the electrochemical system includes a positive electrode cavity, a membrane, a negative electrode cavity, a membrane, a positive electrode cavity, a membrane, and a negative electrode cavity arranged sequentially. Optionally, the electrochemical system includes a negative electrode cavity, a membrane, a positive electrode cavity, a membrane, a negative electrode cavity, a membrane, and a positive electrode cavity arranged sequentially. As an example, the electrochemical system includes, in sequence, a positive electrode cavity, a membrane, a negative electrode cavity, a membrane, a positive electrode cavity, a membrane, a negative electrode cavity, a membrane, a positive electrode cavity, a membrane, and a negative electrode cavity. Optionally, the electrochemical system includes, in sequence, a negative electrode cavity, a membrane, a positive electrode cavity, a membrane, a negative electrode cavity, a membrane, a positive electrode cavity, a membrane, a negative electrode cavity, a membrane, and a positive electrode cavity. For illustrative and not limiting purposes, the two ends of the electrochemical system are either positive or negative electrode cavities, and outside the two ends are cavity walls.

[0077] In conjunction with the first aspect, in some feasible embodiments, the positive and / or negative electrode cavities are light-transmitting. The transmittance of the positive and / or negative electrode cavities is at least 10%, at least 20%, at least 30%, at least 40%, at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, or at least 99%. It should be noted that even if the transmittance of the positive and / or negative electrode cavities is 0, it is still possible to irradiate the positive electrode and / or positive electrode cavity with light emitted from the photoexcitation device, for example, irradiating the interior of the positive electrode cavity, or irradiating the positive electrode and / or acidic liquid within the positive electrode cavity, for example, irradiating the positive electrode and / or acidic liquid within the positive electrode cavity from top to bottom with light emitted from the photoexcitation device. The top of the positive and / or negative electrode cavity can be open, uncovered, or covered with a light-transmitting cover.

[0078] In conjunction with the first aspect, in some feasible implementations, the open-circuit potential of the electrochemical system is ≤2.5V, for example ≤2.4V, ≤2.3V, ≤2.2V, ≤2.1V, ≤2.0V, ≤1.9V, ≤1.8V, ≤1.7V, ≤1.6V, ≤1.5V, ≤1.4V, ≤1.3V, ≤1.2V, ≤1.1V, ≤1.0V, ≤0.9V, ≤0.8V, and the working electrode potential of the electrochemical system is lower than the open-circuit potential of the electrochemical system. When the working electrode potential of the electrochemical system is lower than the open circuit potential of the electrochemical system, the working electrode potential is 0V to 1.5V, for example 0V to 1.0V, for example 0V to 0.8V, for example 0V to 0.6V, for example 0V, 0.1V, 0.2V, 0.3V, 0.4V, 0.5V, 0.6V, 0.7V, 0.8V, etc.

[0079] In conjunction with the first aspect, in some feasible embodiments, the diaphragm includes at least one of polyethylene diaphragm, polypropylene diaphragm, nylon diaphragm, nitrocellulose diaphragm, cellulose acetate diaphragm, polysulfone diaphragm, polyamide diaphragm, polyacrylonitrile diaphragm, polyvinyl chloride diaphragm, polytetrafluoroethylene diaphragm, polyvinylidene fluoride diaphragm, and polycarbonate diaphragm.

[0080] In conjunction with the first aspect, in some feasible implementations, the diaphragm is a microporous membrane.

[0081] For illustrative purposes and not for limitation, the pore size of the battery separator is smaller than Cu. 2+ / Cu + The radius.

[0082] In conjunction with the first aspect, in some feasible implementations, the electrochemical system does not include a conductive clamping material. The term "clamping" as used herein refers to clamping the positive and / or negative electrodes of the battery to be recycled with a conductive material. As an example, the conductive clamping material is an acid-resistant conductive clamping material. As an example, the conductive clamping material is porous. As an example, the conductive clamping material includes at least one of platinum, gold, palladium, lead, titanium, aluminum, copper, stainless steel, graphite, glassy carbon, carbon fiber, graphene, carbon cloth, and carbon felt, such as platinum (e.g., platinum mesh or platinum sheet), gold mesh, palladium mesh, lead mesh, titanium mesh, aluminum mesh, copper mesh, stainless steel mesh, graphite material, carbon material, carbon cloth, or carbon felt. As an example, the conductive clamping material can clamp the positive and / or negative electrodes of the battery into a "sandwich" structure. As an example, the conductive clamping material can be one, two, three, four, or more layers.

[0083] In a second aspect, this application provides the use of an electrochemical system for recycling batteries, such as retired lithium-ion batteries, used lithium-ion batteries, etc.

[0084] In a third aspect, this application provides a method for recycling batteries, the method comprising the following steps:

[0085] (i) Provide an electrochemical system, the electrochemical system comprising a positive electrode cavity, a negative electrode cavity, a membrane, and a photoexcitation device;

[0086] An acidic liquid is provided in the positive electrode cavity;

[0087] An acidic liquid is provided in the negative electrode cavity;

[0088] (ii) Place the positive electrode of the battery to be treated into the acidic liquid in the positive electrode chamber;

[0089] (iii) Place the negative electrode of the battery to be treated into the acidic liquid in the negative electrode cavity;

[0090] (iv) Connect the positive terminal and the negative terminal of the battery to be processed;

[0091] (v) Irradiate the positive electrode with light emitted by the photoexcitation device, for example, irradiate the positive electrode and / or the interior of the positive electrode cavity, for example, irradiate the positive electrode and / or acidic liquid in the positive electrode cavity.

[0092] The present invention improves the leaching rate and significantly accelerates the leaching kinetics by irradiating the battery material (e.g., the positive electrode) from a semiconductor to a conductor by applying an external photoexcitation device during the leaching process.

[0093] In conjunction with the third aspect, after step (v), the mixture in the chamber is subjected to solid-liquid separation, for example by vacuum filtration. Alternatively, solid-liquid separation can be performed after the reaction, for example, after the reaction is complete, the solid-liquid mixture is separated by vacuum filtration or filtration to obtain a metal-rich leachate and activated carbon powder.

[0094] In conjunction with the third aspect, and not wishing to be bound by theory, the electrochemical system includes one or more positive electrode cavities.

[0095] In conjunction with the third aspect, and not wishing to be bound by theory, the electrochemical system includes one or more negative electrode cavities.

[0096] In conjunction with the third aspect, and not wishing to be bound by theory, the electrochemical system includes one or more membranes.

[0097] In conjunction with the third aspect, in some feasible embodiments, the acidic liquid in the positive electrode cavity includes an inorganic acid solution and / or an organic acid solution. Alternatively, the acidic liquid in the positive electrode cavity is an inorganic acid solution and / or an organic acid solution.

[0098] In conjunction with the third aspect, in some feasible embodiments, the acidic liquid in the negative electrode cavity includes an inorganic acid solution and / or an organic acid solution. Alternatively, the acidic liquid in the negative electrode cavity is an inorganic acid solution and / or an organic acid solution.

[0099] In conjunction with the third aspect, in some feasible embodiments, the acidic liquid in the positive electrode cavity comprises an inorganic acid solution, which includes at least one selected from hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, perchloric acid, hydrobromic acid, hydroiodic acid, boric acid, and carbonic acid; or, the inorganic acid solution is composed of at least one selected from hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, perchloric acid, hydrobromic acid, hydroiodic acid, boric acid, and carbonic acid. Alternatively, in some feasible embodiments, the acidic liquid in the positive electrode cavity comprises an inorganic acid solution, which includes at least one selected from hydrochloric acid, sulfuric acid, nitric acid, and phosphoric acid; or, the inorganic acid solution is composed of at least one selected from hydrochloric acid, sulfuric acid, nitric acid, and phosphoric acid.

[0100] In conjunction with the third aspect, in some feasible embodiments, the acidic liquid in the negative electrode cavity comprises an inorganic acid solution, which includes at least one selected from hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, perchloric acid, hydrobromic acid, hydroiodic acid, boric acid, and carbonic acid; or, the inorganic acid solution is composed of at least one selected from hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, perchloric acid, hydrobromic acid, hydroiodic acid, boric acid, and carbonic acid. Alternatively, in some feasible embodiments, the acidic liquid in the negative electrode cavity comprises an inorganic acid solution, which includes at least one selected from hydrochloric acid, sulfuric acid, nitric acid, and phosphoric acid; or, the inorganic acid solution is composed of at least one selected from hydrochloric acid, sulfuric acid, nitric acid, and phosphoric acid.

[0101] In conjunction with the third aspect, in some feasible implementations, the acidic liquid in the positive electrode cavity comprises an organic acid solution, which includes or is composed of at least one of the following: formic acid, acetic acid, propionic acid, butyric acid, octanoic acid, adipic acid, oxalic acid, malonic acid, succinic acid, maleic acid, tartaric acid, benzoic acid, phenylacetic acid, phthalic acid, terephthalic acid, valeric acid, hexanoic acid, decanoic acid, stearic acid, palmitic acid, acrylic acid, ascorbic acid, and malic acid.

[0102] In conjunction with the third aspect, in some feasible implementations, the acidic liquid in the negative electrode cavity comprises an organic acid solution, which includes or is composed of at least one of the following: formic acid, acetic acid, propionic acid, butyric acid, octanoic acid, adipic acid, oxalic acid, malonic acid, succinic acid, maleic acid, tartaric acid, benzoic acid, phenylacetic acid, phthalic acid, terephthalic acid, valeric acid, hexanoic acid, decanoic acid, stearic acid, palmitic acid, acrylic acid, ascorbic acid, and malic acid.

[0103] In conjunction with the third aspect, in some feasible implementations, the concentration of the acidic liquid in the positive electrode cavity is from 0.01 mol / L to 10 mol / L, for example, from 0.01 mol / L to 5 mol / L, for example, from 0.1 mol / L to 5 mol / L, for example, from 0.5 mol / L to 5 mol / L, for example, 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 mol / L, etc., but is not limited to the listed values; other unlisted values ​​or ranges within this range are also applicable.

[0104] In conjunction with the third aspect, in some feasible implementations, the concentration of the acidic liquid in the negative electrode cavity is from 0.01 mol / L to 10 mol / L, for example, from 0.01 mol / L to 5 mol / L, for example, from 0.1 mol / L to 5 mol / L, for example, from 0.5 mol / L to 5 mol / L, for example, 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 mol / L, etc., but is not limited to the listed values; other unlisted values ​​or ranges within this range are also applicable.

[0105] In conjunction with the third aspect, in some feasible embodiments, the volume of the positive electrode cavity is at least 10 mL, for example at least 20 mL, for example at least 30 mL, for example at least 40 mL, for example at least 50 mL, for example at least 60 mL, for example at least 70 mL, for example at least 80 mL, for example at least 90 mL, for example at least 100 mL, for example at least 200 mL, for example at least 300 mL, for example at least 400 mL, for example at least 500 mL, for example at least 600 mL, for example at least 700 mL, for example at least 800 mL, for example at least 900 mL, for example at least 1000 mL, for example at least 20 ... Less than 3000mL, for example, at least 4000mL, for example, at least 5000mL, for example, at least 6000mL, for example, at least 7000mL, for example, at least 8000mL, for example, at least 9000mL, for example, at least 1.5L, for example, at least 2L, for example, at least 3L, for example, at least 4L, for example, at least 5L, for example, at least 6L, for example, at least 7L, for example, at least 8L, for example, at least 9L, for example, at least 10L, for example, at least 20L, for example, at least 30L, for example, at least 40L, for example, at least 50L, for example, at least 60L, for example, at least 70L, for example, at least 80L, for example, at least 90L, for example, at least 100L, etc.

[0106] In conjunction with the third aspect, in some feasible embodiments, the electrochemical system further includes a stirring device. The stirring device can stir the liquid in the positive electrode chamber and / or the negative electrode chamber separately. The stirring speed of the stirring device is at least 10 rpm / min, for example, at least 20 rpm / min, for example, at least 30 rpm / min, for example, at least 40 rpm / min, for example, at least 50 rpm / min, for example, at least 60 rpm / min, for example, at least 70 rpm / min, for example, at least 80 rpm / min, for example, at least 90 rpm / min, for example, at least 100 rpm / min, for example, at least 200 rpm / min, for example, at least 300 rpm / min, for example, at least 400 rpm / min, for example, at least 500 rpm / min.

[0107] In conjunction with the third aspect, the reaction time or reaction interval of the recovery (leaching) method is 30 min to 240 min, for example 60 to 120 min, such as 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240 min, etc., but is not limited to the listed values. Other unlisted values ​​or ranges within this range also apply.

[0108] In conjunction with the third aspect, in some feasible implementations, the wavelength of the light emitted by the photoexcitation device is ≤770nm.

[0109] In conjunction with the third aspect, in some feasible implementations, the wavelength of the light emitted by the photoexcitation device is ≤400nm.

[0110] In conjunction with the third aspect, in some feasible implementations, the wavelength of the light emitted by the photoexcitation device is from 10 nm to 400 nm.

[0111] In conjunction with the third aspect, in some feasible implementations, the wavelength of the light emitted by the photoexcitation device is between 320 nm and 400 nm.

[0112] In conjunction with the third aspect, in some feasible implementations, the wavelength of the light emitted by the photoexcitation device is between 280 nm and 320 nm.

[0113] In conjunction with the third aspect, in some feasible implementations, the wavelength of the light emitted by the photoexcitation device is between 190 nm and 280 nm.

[0114] In conjunction with the third aspect, in some feasible implementations, the wavelength of the light emitted by the photoexcitation device is between 100 nm and 190 nm.

[0115] In conjunction with the third aspect, in some feasible implementations, the wavelength of the light emitted by the photoexcitation device is from 10 nm to 100 nm.

[0116] In conjunction with the third aspect, in some feasible implementations, the wavelength of the light emitted by the photoexcitation device is, for example, 180nm, 185nm, 190nm, 195nm, 200nm, 205nm, 210nm, 215nm, 220nm, 225nm, 230nm, 235nm, 240nm, 245nm, 250nm, 254nm, 260nm, 265nm, 270nm, 275nm, 280nm, 285nm, 290nm. The range includes m, 295nm, 300nm, 305nm, 310nm, 315nm, 320nm, 325nm, 330nm, 335nm, 340nm, 345nm, 350nm, 355nm, 360nm, 365nm, 370nm, 375nm, 380nm, 385nm, 390nm, 395nm, 400nm, etc., but is not limited to the listed values. Other unlisted values ​​or ranges within this range also apply.

[0117] In conjunction with the third aspect, in some feasible implementations, the power of the photoexcitation device is ≥3W.

[0118] In conjunction with the third aspect, in some feasible implementations, the power of the photoexcitation device is ≥5W.

[0119] In conjunction with the third aspect, in some feasible implementations, the power of the photoexcitation device is ≥7W.

[0120] In conjunction with the third aspect, in some feasible implementations, the power of the photoexcitation device is ≥9W.

[0121] In conjunction with the third aspect, in some feasible implementations, the power of the photoexcitation device is ≥11W.

[0122] In conjunction with the third aspect, in some feasible implementations, the power of the photoexcitation device is ≥26W.

[0123] In conjunction with the third aspect, in some feasible implementations, the power of the photoexcitation device is ≥30W.

[0124] In conjunction with the third aspect, in some feasible implementations, the power of the photoexcitation device is ≥36W.

[0125] In conjunction with the third aspect, in some feasible implementations, the power of the photoexcitation device is ≥45W.

[0126] In conjunction with the third aspect, in some feasible implementations, the power of the photoexcitation device is ≥55W.

[0127] In conjunction with the third aspect, in some feasible implementations, the power of the photoexcitation device is ≥65W.

[0128] In conjunction with the third aspect, in some feasible implementations, the power of the photoexcitation device is ≥75W.

[0129] In conjunction with the third aspect, in some feasible implementations, the power of the photoexcitation device is ≥100W.

[0130] In conjunction with the third aspect, in some feasible implementations, the power of the photoexcitation device is ≥140W.

[0131] In conjunction with the third aspect, in some feasible implementations, the power of the photoexcitation device is ≥200W.

[0132] In conjunction with the third aspect, in some feasible embodiments, the acidic liquid in the positive electrode cavity is doped with nanobubbles, the diameter of which does not exceed 1000 nm, for example, not exceeding 900 nm, not exceeding 800 nm, not exceeding 700 nm, not exceeding 500 nm, not exceeding 400 nm, not exceeding 300 nm, not exceeding 200 nm, for example, 1 nm to 200 nm, for example, 10 nm to 200 nm, for example, 50 nm to 200 nm, for example, 60 nm to 190 nm, for example, 60 nm to 180 nm. 0nm, for example, 60nm to 170nm, for example, 60nm to 160nm, for example, 60nm to 150nm, for example, 60nm to 140nm, for example, 60nm to 130nm, for example, 60nm to 120nm, for example, 70nm to 120nm, for example, 80nm to 120nm, for example, 90nm to 120nm, for example, 80nm to 110nm, for example, approximately 120nm, for example, approximately 110nm, for example, approximately 100nm, for example, approximately 90nm, for example, approximately 80nm.

[0133] In conjunction with the third aspect, in some feasible embodiments, the acidic liquid in the negative electrode cavity is doped with nanobubbles, the diameter of which does not exceed 1000 nm, for example, not exceeding 900 nm, not exceeding 800 nm, not exceeding 700 nm, not exceeding 500 nm, not exceeding 400 nm, not exceeding 300 nm, not exceeding 200 nm, for example, 1 nm to 200 nm, for example, 10 nm to 200 nm, for example, 50 nm to 200 nm, for example, 60 nm to 190 nm, for example, 60 nm to 180 nm. 0nm, for example, 60nm to 170nm, for example, 60nm to 160nm, for example, 60nm to 150nm, for example, 60nm to 140nm, for example, 60nm to 130nm, for example, 60nm to 120nm, for example, 70nm to 120nm, for example, 80nm to 120nm, for example, 90nm to 120nm, for example, 80nm to 110nm, for example, approximately 120nm, for example, approximately 110nm, for example, approximately 100nm, for example, approximately 90nm, for example, approximately 80nm.

[0134] In conjunction with the third aspect, in some feasible implementations, the electrochemical system constitutes a galvanic cell system.

[0135] In conjunction with the third aspect, in some feasible implementations, the electrodes of the electrochemical system are a two-electrode system.

[0136] In conjunction with the third aspect, in some feasible implementations, the electrochemical system does not include an external power source, meaning that the electrochemical system can recycle battery materials without the need for an additional power supply device (e.g., a power source).

[0137] In conjunction with the third aspect, in some feasible implementations, the electrochemical system includes conductive connecting components, which may be, for example, conductive wires, filaments, sheets, tubes, blocks, powders, etc.

[0138] In conjunction with the third aspect, in some feasible implementation schemes, the batteries to be recycled include at least one of lithium-ion batteries, sodium-ion batteries, potassium-ion batteries, lithium-sulfur batteries, sodium-sulfur batteries, and potassium-sulfur batteries.

[0139] In conjunction with the third aspect, in some feasible embodiments, a positive electrode cavity and a negative electrode cavity constitute a cavity combination, and the electrochemical system includes one or more such cavity combinations, with the positive electrode cavity and the negative electrode cavity separated by a membrane. The multiple combinations include two, three, four, or more combinations, etc. As an example, the electrochemical system includes a positive electrode cavity, a membrane, and a negative electrode cavity arranged sequentially. Optionally, the electrochemical system includes a negative electrode cavity, a membrane, and a positive electrode cavity arranged sequentially. As an example, the electrochemical system includes a positive electrode cavity, a membrane, a negative electrode cavity, a membrane, a positive electrode cavity, a membrane, and a negative electrode cavity arranged sequentially. Optionally, the electrochemical system includes a negative electrode cavity, a membrane, a positive electrode cavity, a membrane, a negative electrode cavity, a membrane, and a positive electrode cavity arranged sequentially. As an example, the electrochemical system includes, in sequence, a positive electrode cavity, a membrane, a negative electrode cavity, a membrane, a positive electrode cavity, a membrane, a negative electrode cavity, a membrane, a positive electrode cavity, a membrane, and a negative electrode cavity. Optionally, the electrochemical system includes, in sequence, a negative electrode cavity, a membrane, a positive electrode cavity, a membrane, a negative electrode cavity, a membrane, a positive electrode cavity, a membrane, a negative electrode cavity, a membrane, and a positive electrode cavity. For illustrative and not limiting purposes, the two ends of the electrochemical system are either positive or negative electrode cavities, and outside the two ends are cavity walls.

[0140] In conjunction with the third aspect, in some feasible implementations, the positive and / or negative electrode cavities are light-transmitting. The transmittance of the positive and / or negative electrode cavities is at least 10%, at least 20%, at least 30%, at least 40%, at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, or at least 99%. It should be noted that even if the transmittance of the positive and / or negative electrode cavities is 0, it is still possible to irradiate the positive electrode and / or positive electrode cavity with light emitted from the photoexcitation device, for example, irradiating the interior of the positive electrode cavity, or irradiating the positive electrode and / or acidic liquid within the positive electrode cavity, for example, irradiating the positive electrode and / or acidic liquid within the positive electrode cavity from top to bottom with light emitted from the photoexcitation device. The top of the positive and / or negative electrode cavity can be open, uncovered, or covered with a light-transmitting cover.

[0141] In conjunction with the third aspect, in some feasible implementations, the open-circuit potential of the electrochemical system is ≤2.5V, for example ≤2.4V, ≤2.3V, ≤2.2V, ≤2.1V, ≤2.0V, ≤1.9V, ≤1.8V, ≤1.7V, ≤1.6V, ≤1.5V, ≤1.4V, ≤1.3V, ≤1.2V, ≤1.1V, ≤1.0V, ≤0.9V, ≤0.8V, and the working electrode potential of the electrochemical system is lower than the open-circuit potential of the electrochemical system. When the working electrode potential of the electrochemical system is lower than the open circuit potential of the electrochemical system, the working electrode potential is 0V to 1.5V, for example 0V to 1.0V, for example 0V to 0.8V, for example 0V to 0.6V, for example 0V, 0.1V, 0.2V, 0.3V, 0.4V, 0.5V, 0.6V, 0.7V, 0.8V, etc.

[0142] In conjunction with the third aspect, in some feasible embodiments, the diaphragm includes at least one of polyethylene diaphragm, polypropylene diaphragm, nylon diaphragm, nitrocellulose diaphragm, cellulose acetate diaphragm, polysulfone diaphragm, polyamide diaphragm, polyacrylonitrile diaphragm, polyvinyl chloride diaphragm, polytetrafluoroethylene diaphragm, polyvinylidene fluoride diaphragm, and polycarbonate diaphragm.

[0143] In conjunction with the third aspect, in some feasible implementations, the diaphragm is a microporous membrane.

[0144] In conjunction with the third aspect, in some feasible implementations, the method does not include the processes of crushing, ultrasonically vibrating, roasting, sieving, magnetically separating, and grinding the positive and negative electrodes of the batteries to be recycled.

[0145] In conjunction with the third aspect, in some feasible implementations, the electrochemical system does not include a conductive clamping material. The term "clamping" as used herein refers to clamping the positive and / or negative electrodes of the battery to be recycled with a conductive material. As an example, the conductive clamping material is an acid-resistant conductive clamping material. As an example, the conductive clamping material is porous. As an example, the conductive clamping material includes at least one of platinum, gold, palladium, lead, titanium, aluminum, copper, stainless steel, graphite, glassy carbon, carbon fiber, graphene, carbon cloth, and carbon felt, such as platinum (e.g., platinum mesh or platinum sheet), gold mesh, palladium mesh, lead mesh, titanium mesh, aluminum mesh, copper mesh, stainless steel mesh, graphite material, carbon material, carbon cloth, or carbon felt. As an example, the conductive clamping material can clamp the positive and / or negative electrodes of the battery into a "sandwich" structure. As an example, the conductive clamping material can be one, two, three, four, or more layers.

[0146] In some embodiments, the step of incorporating nanobubbles into the acidic liquid in the positive and / or negative electrode cavities may include:

[0147] (1) Add the acidic liquid to the container;

[0148] (2) Pass the target gas into the container to remove the original gas in the container;

[0149] (3) Close the container;

[0150] (4) Treating an acidic liquid for a certain period of time using at least one of the following methods: mechanical stirring, acoustic vibration, electrolysis, atomization, hydrodynamic cavitation, optical cavitation, which may be methods already implemented in the prior art, such as those described in CN210845927U.Furthermore, the time for treating the liquid using this method or these methods may be at least 1 second, at least 2 seconds, at least 3 seconds, at least 4 seconds, at least 5 seconds, at least 6 seconds, at least 7 seconds, at least 8 seconds, at least 9 seconds, at least 10 seconds, at least 11 seconds, at least 12 seconds, at least 13 seconds, at least 14 seconds, at least 15 seconds, at least 16 seconds, at least 17 seconds, at least 18 seconds, at least 19 seconds, at least 20 seconds, at least 21 seconds, at least 22 seconds, at least 23 seconds, at least 24 seconds, at least 25 seconds, at least 26 seconds, at least 27 seconds, at least 28 seconds, at least 29 seconds, at least 30 seconds, at least 31 seconds, at least 32 seconds, or at least 33 seconds. At least 34 seconds, at least 35 seconds, at least 36 seconds, at least 37 seconds, at least 38 seconds, at least 39 seconds, at least 40 seconds, at least 41 seconds, at least 42 seconds, at least 43 seconds, at least 44 seconds, at least 45 seconds, at least 46 seconds, at least 47 seconds, at least 48 seconds, at least 49 seconds, at least 50 seconds, at least 51 seconds, at least 52 seconds, at least 53 seconds, at least 54 seconds, at least 55 seconds, at least 56 seconds, at least 57 seconds, at least 58 seconds, at least 59 seconds, at least 60 seconds, at least 2 minutes, at least 3 minutes, at least 4 minutes, at least 5 minutes, at least 6 minutes, at least 7 minutes, at least 8 minutes, at least 9 minutes, at least 10 minutes, at least 11 minutes At least 12 minutes, at least 13 minutes, at least 14 minutes, at least 15 minutes, at least 16 minutes, at least 17 minutes, at least 18 minutes, at least 19 minutes, at least 20 minutes, at least 21 minutes, at least 22 minutes, at least 23 minutes, at least 24 minutes, at least 25 minutes, at least 26 minutes, at least 27 minutes, at least 28 minutes, at least 29 minutes, at least 30 minutes, at least 31 minutes, at least 32 minutes, at least 33 minutes, at least 34 minutes, at least 35 minutes, at least 36 minutes, at least 37 minutes, at least 38 minutes, at least 39 minutes, at least 40 minutes, at least 41 minutes, at least 42 minutes, at least 43 minutes, at least 44 minutes, at least 45 minutes, at least 46 minutes, at least 47 minutes, at least 48 minutes, at least 49 minutes, at least 50 minutes, at least 51 minutes, at least 52 minutes, at least 53 minutes, at least 54 minutes, at least 55 minutes, at least 56 minutes, at least 57 minutes, at least 58 minutes, at least 59 minutes, at least 60 minutes, at least 2 hours, at least 3 hours, at least 4 hours, at least 5 hours, at least 6 hours, at least 7 hours, at least 8 hours, at least 9 hours, at least 10 hours, at least 11 hours, at least 12 hours, at least 13 hours, at least 14 hours, at least 15 hours, at least 16 hours, at least 17 hours, at least 18 hours, at least 19 hours, at least 20 hours, at least 21 hours, at least 22 hours, at least 23 hours, at least 24 hours.As an exemplary implementation, the liquid can be treated in this manner or these methods for a period of time ranging from 30 seconds to 1 hour, for example, 1 minute to 60 minutes, 1 minute to 55 minutes, 1 minute to 50 minutes, 1 minute to 45 minutes, 1 minute to 40 minutes, 1 minute to 35 minutes, 1 minute to 30 minutes, 2 minutes to 30 minutes, 3 minutes to 30 minutes, 4 minutes to 30 minutes, or 5 minutes to 30 minutes.

[0151] In some embodiments, the gas in the nanobubbles can be air, or a single component or several components of air, or an inert gas, etc. As an exemplary embodiment, the gas in the nanobubbles may include one or more of nitrogen (N2), oxygen (O2), carbon dioxide (CO2), ozone (O3), nitric oxide (NO), nitrogen dioxide (NO2), helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and radon (Rn).

[0152] As an exemplary embodiment, the process of preparing a liquid containing nanobubbles in an acidic liquid includes treating the acidic liquid using at least one of the following methods: mechanical stirring, acoustic vibration, electrolysis, atomization, hydrodynamic cavitation, optical cavitation, for example, mechanical stirring, specifically, stirring the acidic liquid using high-speed rotating blades.

[0153] Furthermore, for example, an acidic liquid can be placed in a container, and then the acidic liquid can be stirred by high-speed rotating blades to generate nanobubbles. Specifically, the rotation speed of the blades can be 10,000 to 100,000 rpm / min, preferably 20,000 to 100,000 rpm / min, preferably 30,000 to 100,000 rpm / min, preferably 40,000 to 100,000 rpm / min, preferably 50,000 to 100,000 rpm / min, preferably 60,000 to 100,000 rpm / min, preferably 70,000 to 100,000 rpm / min, preferably 80,000 to 100,000 rpm / min. Alternatively, the rotation speed of the blades can be 10,000 to 90,000 rpm / min, 10,000 to 80,000 rpm / min. min, 10,000 to 70,000 rpm / min, 10,000 to 60,000 rpm / min, 10,000 to 50,000 rpm / min, or 10,000 to 40,000 rpm / min, for example, approximately 10,000 rpm / min, approximately 20,000 rpm / min, approximately 30,000 rpm / min, approximately 40,000 rpm / min, approximately 50,000 rpm / min, approximately 60,000 rpm / min, approximately 70,000 rpm / min, approximately 80,000 rpm / min, approximately 90,000 rpm / min, or approximately 100,000 rpm / min.

[0154] In some embodiments, the galvanic cell system constructed in this application further includes a separator within its chamber to separate the positive and negative electrodes, thus dividing the galvanic cell system into a positive electrode chamber and a negative electrode chamber. This separator only allows small molecules (such as water molecules) to pass through, while leachable metal ions (Cu) are excluded. 2+ ), valuable metal ions (Li) + Co 2+ Ni 2+ Mn 2+ (etc.) cannot pass through the diaphragm, therefore Cu 2+ The electrolyte is confined in the negative electrode chamber and does not enter the positive electrode chamber; valuable metal ions are confined in the electrolyte in the positive electrode chamber and do not enter the negative electrode chamber, thus realizing Cu 2+ Separation from valuable metal ions. The electrolyte in the negative electrode chamber can be further recovered to obtain Cu powder through electroreduction. The voltage for electrolytic copper is 1.8–2.5V, generally controlled at 1.9V.

[0155] In some embodiments, the separator is obtained from the disassembled battery, thus enabling full utilization of each part of the disassembled battery. Preferably, the separator is a polyethylene separator or a polypropylene separator, which has a small and uniformly distributed pore size, capable of blocking Cu. 2+ It allows the passage of valuable metal ions while also having a certain flux.

[0156] In some feasible implementations, the method of the present invention further includes simply separating the positive and negative electrodes of the battery, i.e., disassembling the battery to obtain positive and negative electrode sheets. Here, "disassembly" refers to simply separating the positive and negative electrode sheets without requiring further processing. Traditional recycling methods for retired lithium-ion batteries require a series of operations, including disassembly, crushing, sieving, sorting, magnetic separation, grinding, primary grinding, positive electrode material sorting, and secondary grinding. Therefore, the method of the present invention avoids the cumbersome pretreatment process for the positive electrode material. It should be noted that even after further disassembly, crushing, sieving, sorting, magnetic separation, grinding, primary grinding, positive electrode material sorting, and secondary grinding of the battery's positive electrode material, the resulting material can still be recycled using the electrochemical system and method of the present invention.

[0157] Furthermore, this invention does not require the use of conductive materials to sandwich or process the battery positive or negative electrode materials to be recycled into a "sandwich" structure.

[0158] In this invention, the negative electrode current collector is copper foil, and the negative electrode active material includes, but is not limited to, one or more of graphite, activated carbon, and lithium titanate. Changes in the proportion of the negative electrode active material will not affect the output voltage of the galvanic cell because the negative electrode active material does not participate in the reaction; only the negative electrode current collector (copper foil) participates in the electrochemical reaction.

[0159] The term "retired battery" as used herein may be used interchangeably with "used battery". It should be noted that the electrochemical system and method of this application can also be used to recycle new batteries, semi-finished batteries, defective batteries, substandard batteries, and so on.

[0160] As an example, the negative electrode active material of the lithium-ion battery disclosed herein is graphite, and the positive electrode active material is mainly LiCoO2 and LiNi. x Co y Mn z O2 (where x+y+z=1) and lithium transition metal oxides such as LiMn2O4. As an example, the positive electrode of the lithium-ion battery in this disclosure is composed of: positive electrode active material (lithium transition metal oxide), a small amount of conductive agent (generally acetylene black) and organic binder, which are uniformly mixed and then coated on an aluminum foil current collector to form a positive electrode.

[0161] Without any particular limitation, the recycling method of the present invention includes a very simple process, specifically discharging the battery, disassembling and removing the casing (e.g., manually or mechanically in a glove box), separating the separator and the negative electrode, and removing the positive electrode sheet (i.e., the positive electrode material); drying the positive electrode sheet to allow the electrolyte and other organic solvents to evaporate. This simple process avoids the complex pretreatment process before leaching.

[0162] In the system of the present invention, the present invention uses an external photoexcitation device (e.g., ultraviolet lamp) to enhance the battery-like structure and simultaneously recover the positive and negative electrodes, wherein the leaching rate of lithium reaches more than 90%, the leaching rate of cobalt reaches more than 90%, the leaching rate of nickel reaches more than 90%, and the leaching rate of manganese reaches more than 90%.

[0163] The terms "leaching," "extraction," and "extraction" used in this paper are used interchangeably. The terms "leaching efficiency" and "leaching rate" are also used interchangeably. The formula for calculating the leaching efficiency is as follows:

[0164] Leaching rate = m / M × 100%

[0165] In the above formula, m is the content of the metal element in the leaching solution, and M is the total content of the metal element in the cathode material to be recovered.

[0166] Unless otherwise specified herein, the purity grade of the substances purchased or used herein is chemically pure, analytically pure, or superior pure, preferably analytically pure, and more preferably superior pure.

[0167] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0168] (1) Compared with the traditional method of electrochemical reduction to recycle the cathode of retired batteries, the method of the present invention is more economical, has better leaching effect, and faster leaching kinetics;

[0169] (2) The present invention adopts a battery-like structure to simultaneously recover valuable elements (e.g., lithium, cobalt, nickel, manganese) in the positive electrode material and copper sheets in the negative electrode material of retired lithium-ion batteries, without the need to reprocess the positive and negative electrode materials;

[0170] (3) The present invention uses an external photoexcitation device to irradiate the battery material during the leaching process to excite it to become a conductor, which has stronger conductivity and a larger output current, thereby improving the leaching rate and significantly accelerating the leaching kinetics.

[0171] (4) The present invention uses a primary cell method to simultaneously recover the positive and negative electrodes of the battery, which not only realizes the recycling of resources but also allows it to perform work externally, resulting in lower energy consumption. Attached Figure Description

[0172] Figure 1 A schematic diagram of the electrochemical system described in this invention is shown.

[0173] Figure 2 A roadmap of the recycling process in Example 1 is shown;

[0174] Figure 3 The leaching rates of Li and Co elements in Example 1 at different working electrode potentials are shown.

[0175] Figure 4 The leaching rates of Li and Co elements in Comparative Example 1' at different working electrode potentials are shown.

[0176] Figure 5 The curves showing the current output of Example 1 and Comparative Example 1' under 0V conditions as a function of time are shown.

[0177] Figure 6 The leaching rates of Li and Co elements in Comparative Example 1” at different working electrode potentials are shown.

[0178] Figure 7 The leaching rates of Li and Co elements at different working electrode potentials are shown in Example 2;

[0179] Figure 8 The leaching rates of Li and Co elements in Comparative Example 2 at different working electrode potentials are shown.

[0180] Figure 9 The leaching rates of Li and Co elements at different working electrode potentials are shown in Example 3;

[0181] Figure 10 The leaching rates of Li and Co elements in Comparative Example 3 at different working electrode potentials are shown. Detailed Implementation

[0182] To better explain the present invention, the embodiments of this application will be described in detail below with reference to specific examples. However, those skilled in the art will understand that the following examples are only for illustrating the present application and should not be regarded as limiting the scope of the present application. Unless otherwise specified in the examples, conventional conditions or conditions recommended by the manufacturer are followed. Reagents or instruments used without specified manufacturers are all conventional products that can be purchased commercially.

[0183] Unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. Further understanding is that terms, such as those defined in common dictionaries, are interpreted in accordance with their meaning in the context of the relevant field and are not idealized or overly formal, unless expressly defined herein.

[0184] Unless otherwise stated in this document or there is a clear contradiction in the context, all methods described herein may be performed in any suitable order.

[0185] Unless otherwise stated, the use of any and all embodiments or exemplary language (such as "for example") provided herein is intended only to better illustrate the invention and not to limit the scope of the invention. Unless explicitly stated otherwise, the language in this specification should not be construed as indicating that any element is essential to carrying out the invention.

[0186] As used in this application, the term "about" is used to describe and indicate small variations. When used in conjunction with an event or situation, the term may refer to examples in which the event or situation occurred precisely and examples in which the event or situation occurred very approximately. For example, when used in conjunction with numerical values, the term may refer to a range of variation less than or equal to ±10% of the numerical value, such as less than or equal to ±5%, less than or equal to ±4%, less than or equal to ±3%, less than or equal to ±2%, less than or equal to ±1%, less than or equal to ±0.5%, less than or equal to ±0.1%, or less than or equal to ±0.05%. Additionally, quantities, ratios, and other numerical values ​​are sometimes presented in range format in this application. It should be understood that such range format is for convenience and brevity and should be interpreted flexibly to include not only numerical values ​​explicitly specified as range limits but also all individual numerical values ​​or subranges covered within the range, as if each numerical value and subrange were explicitly specified.

[0187] The exemplary invention described herein may suitably omit any one or more limiting elements, which are not specifically disclosed herein. Therefore, terms such as “comprising,” “including,” “containing,” etc., should be interpreted broadly and non-limitingly. Furthermore, the terminology used herein is for descriptive purposes without limitation, and it is unintentional to use terms that do not include any equivalent characteristics, but only to describe a portion of their characteristics; however, various modifications are possible within the scope of the invention according to the claims. Therefore, while the invention has been specifically disclosed through preferred embodiments and optional features, variations of the invention embodied by the modifications disclosed herein may be noted by those skilled in the art, and such modifications and variations are considered to be within the scope of the invention.

[0188] "Prepared from" is synonymous with "comprising". The terms "comprising", "including", "having", "containing", or any other variations thereof as used herein are intended to cover non-exclusive inclusion. For example, a composition, step, method, article, or apparatus that includes the listed elements is not necessarily limited to those elements, but may include other elements not expressly listed or elements inherent to such composition, step, method, article, or apparatus.

[0189] The conjunction "composed of..." excludes any unspecified elements, steps, or components. If used in a claim, this phrase makes the claim closed, excluding materials other than those described, except for associated conventional impurities. When the phrase "composed of..." appears in a clause of the body of a claim rather than immediately following it, it limits only the elements described in that clause; other elements are not excluded from the claim as a whole.

[0190] When a quantity, concentration, or other value or parameter is expressed as a range, a preferred range, or a range defined by a series of upper and lower preferred values, this should be understood as specifically disclosing all ranges formed by any pair of any upper or preferred value with any lower or preferred value, regardless of whether the range is disclosed individually. For example, when the range “1 to 10” is disclosed, the described range should be interpreted as including ranges “1 to 10”, “1 to 9”, “1 to 8”, “1 to 7”, “1 to 6”, “1 to 5”, “1 to 4”, “1 to 3”, “1 to 2”, “1 to 3 and 5 to 10”, “1 to 4 and 8”, etc. When numerical ranges are described herein, unless otherwise stated, the range is intended to include its endpoints and all integers and fractions within that range.

[0191] In the detailed description and claims, a list of items connected by the terms "at least one of," "at least one of," "at least one of," or other similar terms may mean any combination of the listed items. For example, if items A and B are listed, then the phrase "at least one of A and B" means only A; only B; or A and B. In another example, if items A, B, and C are listed, then the phrase "at least one of A, B, and C" means only A; or only B; only C; A and B (excluding C); A and C (excluding B); B and C (excluding A); or all of A, B, and C. Item A may contain a single element or multiple elements. Item B may contain a single element or multiple elements. Item C may contain a single element or multiple elements.

[0192] Furthermore, the terms "first," "second," and "third" as used herein are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first," "second," or "third" may explicitly or implicitly include at least one of that feature. In the description of embodiments of this disclosure, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0193] Example 1

[0194] An electrochemical system for recycling retired lithium-ion batteries, the electrochemical system comprising a positive electrode cavity, a negative electrode cavity, a separator, and a photoexcitation device; an acidic liquid is disposed in the positive electrode cavity; an acidic liquid is disposed in the negative electrode cavity.

[0195] The method for recycling retired lithium-ion batteries includes the following steps:

[0196] (1) Simple disassembly

[0197] The retired lithium-ion battery is fully discharged and then manually disassembled in a glove box filled with inert gas to obtain the positive electrode material, negative electrode material, and separator. The positive electrode material and negative electrode material are dried to allow the electrolyte and other organic solvents to evaporate.

[0198] (2) Recycling lithium, cobalt, copper, etc. from battery-like structures:

[0199] After the positive and negative electrode materials are dried, sulfuric acid is added to the battery-like system made of the positive and negative electrode materials. The positive electrode is the retired lithium-ion battery positive electrode material, and the negative electrode is the retired lithium-ion battery negative electrode material. The separator is a battery PP (polypropylene) separator. The reaction temperature is 30℃, the reaction time is 120 min, the sulfuric acid concentration is 1 mol / L, the working electrode potential is 0 to 0.6 V, and the positive electrode is irradiated with a 365 nm ultraviolet lamp (UV) (power 45 W). Taking a working electrode voltage of 0.2 V as an example, the reaction temperature is 30℃, the reaction time is 120 min, the sulfuric acid concentration is 1 mol / L, and the concentration of metal ions in the leaching solution is analyzed by ICP. The calculated leaching rates of lithium and cobalt are >96.53% and >90.25%, respectively, and the open circuit potential is 0.82 V. After the reaction is completed, the solid-liquid mixture is filtered and separated to obtain a metal-rich leaching solution. The experiment was adjusted to the following conditions: sulfuric acid concentration 1 mol / L, positive and negative electrode chamber volumes 100 ml each, stirring speed 300 rpm, reaction temperature 30℃, and working electrode voltage 0 V. ICP analysis was used to analyze the concentration of metal ions in the leaching solution. The final leaching rates for lithium and cobalt were >97.89% and >97.14%, respectively, with an open-circuit potential of 0.82 V. Furthermore, under similar conditions, adjusting the working electrode voltage to 0.4 V and 0.6 V yielded similar leaching rates for lithium and cobalt.

[0200] Figure 2 A roadmap of the recycling process in Example 1 is shown; Figure 3 The leaching rates of Li and Co elements at different working electrode potentials in Example 1 are shown.

[0201] The recycling method in Example 1 does not require a series of operations such as disassembling, crushing, sieving, sorting, magnetic separation, grinding, primary grinding, positive electrode material sorting, secondary grinding, crushing, ultrasonic oscillation, and calcination of the positive electrode material.

[0202] The recycling method in Example 1 does not require the processes of crushing, ultrasonic oscillation, calcination, sieving, magnetic separation, and grinding of the negative electrode material of the lithium-ion battery.

[0203] Similar technical effects can be achieved by adjusting the sulfuric acid solution concentration to 0.2 mol / L, 0.4 mol / L, 0.8 mol / L, 1.2 mol / L, 1.5 mol / L, 2.0 mol / L, 2.5 mol / L, 3.0 mol / L, 3.5 mol / L, and 4.0 mol / L. Furthermore, high leaching rates can also be achieved simultaneously for Ni and Mn in the cathode.

[0204] Comparative Example 1'

[0205] The recovery or leaching process of Comparative Example 1' was basically the same as that of Example 1, except that ultraviolet light irradiation was not used during the leaching process of the galvanic cell. The reaction temperature was 30°C, the reaction time was 120 min, the sulfuric acid concentration was 1 mol / L, the positive electrode chamber and the negative electrode chamber were 100 ml each, the stirring speed was 300 rpm, the working electrode voltage was 0 V, and the concentration of metal ions in the leaching solution was analyzed by ICP. The final leaching rates of lithium and cobalt were 53.89% and 54.24%, respectively, and the open circuit potential was 0.81 V. Figure 4 The leaching rates of Li and Co elements in Comparative Example 1' at different working electrode potentials are shown.

[0206] Under the same test conditions as in Example 1, the leaching rate of Li in Example 1 reached 90.83% after approximately 40 minutes, while the leaching rate of Comparative Example 1' (without UV irradiation) was 53.89% after 120 minutes. Figure 5 The curves showing the current output over time for Example 1 (with UV excitation) and Comparative Example 1' (without UV excitation) under 0V conditions are presented. It can be observed that Example 1 outputs a larger current and performs more work. This demonstrates that the photoexcitation device of the present invention significantly enhances the leaching effect and reduces energy consumption compared to Comparative Example 1' without a photoexcitation device. This fully illustrates the crucial role of photoexcitation, which can significantly increase the output current and substantially improve the leaching rate and leaching kinetics.

[0207] Comparative Example 1”

[0208] The recovery or leaching process of Comparative Example 1” is basically the same as that of Example 1, except that an external voltage is added to the leaching system in Comparative Example 1” to do work (i.e., electric field driven reduction leaching), and ultraviolet light irradiation is not used in the leaching process of Comparative Example 1”. The reaction temperature is 30°C, the reaction time is 120 min, the sulfuric acid concentration is 1 mol / L, the working electrode potential is -0.5 to -0.1 V, the positive electrode chamber and negative electrode chamber volumes are 100 ml, the stirring speed is 300 rpm, the working electrode voltage is -0.4 V, and the concentration of metal ions in the leaching solution is analyzed by ICP. The final leaching rates of lithium and cobalt are >56.89% and >56.03%, respectively, and the open circuit potential is 0.81 V. Figure 6 The leaching rates of Li and Co elements in Comparative Example 1” at different working electrode potentials are shown.

[0209] In Comparative Example 1 (even with an external voltage applied, but without UV irradiation), the leaching rate of Li was 56.99% after 120 minutes; the leaching rate of Co was 56.03% after 120 minutes. Comparative Example 1 demonstrates that even with an external power source for electrolytic recycling of retired lithium-ion batteries, good leaching cannot be achieved without UV excitation.

[0210] Example 2

[0211] An electrochemical system for recycling retired lithium-ion batteries, the electrochemical system comprising a positive electrode cavity, a negative electrode cavity, a separator, and a photoexcitation device; an acidic liquid is disposed in the positive electrode cavity; an acidic liquid is disposed in the negative electrode cavity.

[0212] The method for recycling retired lithium-ion batteries includes the following steps:

[0213] (1) Simple disassembly

[0214] The retired lithium-ion battery is fully discharged and then manually disassembled in a glove box filled with inert gas to obtain the positive electrode material, negative electrode material, and separator. The positive electrode material and negative electrode material are dried to allow the electrolyte and other organic solvents to evaporate.

[0215] (2) Preparation of nanobubbles

[0216] Pure water was saturated with oxygen for 20 minutes using a bubble generator. The oxygen-saturated water was then poured into a mechanical stirrer, which was turned on while oxygen was simultaneously introduced. The blades were set to rotate rapidly for 4 minutes. After stirring, the aqueous solution containing oxygen-containing nanobubbles (approximately 150 nm in diameter) was poured out for later use.

[0217] (3) Recycling lithium, cobalt, copper, etc. from battery-like structures:

[0218] After the positive and negative electrode materials are dried, a sulfuric acid solution prepared with a certain volume of nanobubble aqueous solution is added as a leaching agent to the battery-like system made of the positive and negative electrode materials. The positive electrode is the retired lithium-ion battery positive electrode material, and the negative electrode is the retired lithium-ion battery negative electrode material. The separator is a battery PP separator. The reaction temperature is 30℃, the reaction time is 120 min, the concentration of sulfuric acid mixed with nanobubbles is 1 mol / L, the working electrode potential is 0 to 0.6V, and the positive electrode is irradiated with a 365nm ultraviolet lamp (UV) (power 45W). Taking a working electrode voltage of 0.2V as an example, the reaction temperature is 30℃, the reaction time is 120 min, the concentration of sulfuric acid mixed with nanobubbles is 1 mol / L, and the concentration of metal ions in the leaching solution is analyzed by ICP. The leaching rates of lithium and cobalt are calculated to be >98.53% and >98.24%, respectively, and the open circuit potential is 0.84V. After the reaction is completed, the solid-liquid mixture is filtered and separated to obtain a metal-rich leaching solution. The experiment was adjusted to the following conditions: sulfuric acid concentration containing nanobubbles 1 mol / L, positive and negative electrode volumes 100 ml each, stirring speed 300 rpm, reaction temperature 30℃, and working electrode voltage 0 V. The resulting leaching rates of lithium and cobalt were >99.89% and >99.64%, respectively, with an open-circuit potential of 0.84 V. Furthermore, under similar conditions, adjusting the working electrode voltage to 0.4 V and 0.6 V yielded similar leaching rates of lithium and cobalt. Figure 7 The leaching rates of Li and Co elements at different working electrode potentials are shown in Example 2.

[0219] The recycling method in Example 2 does not require a series of operations such as disassembling, crushing, sieving, sorting, magnetic separation, grinding, primary grinding, positive electrode material sorting, secondary grinding, crushing, ultrasonic oscillation, and calcination of the positive electrode material.

[0220] The recycling method in Example 2 does not require the processes of crushing, ultrasonic oscillation, calcination, sieving, magnetic separation, and grinding of the negative electrode material of the lithium-ion battery.

[0221] Similar technical effects can be achieved by adjusting the concentration of the sulfuric acid solution containing nanobubbles to 0.2 mol / L, 0.4 mol / L, 0.8 mol / L, 1.2 mol / L, 1.5 mol / L, 2.0 mol / L, 2.5 mol / L, 3.0 mol / L, 3.5 mol / L, and 4.0 mol / L. Furthermore, high leaching rates can also be achieved simultaneously for Ni and Mn in the cathode.

[0222] Comparative Example 2

[0223] The recovery or leaching process of Comparative Example 2 was basically the same as that of Example 2, except that ultraviolet light irradiation was not used in the leaching process of the galvanic cell. The reaction temperature was 30°C, the reaction time was 120 min, the concentration of sulfuric acid mixed with nanobubbles was 1 mol / L, the volumes of the positive and negative electrode chambers were 100 ml, the stirring speed was 300 rpm, the working electrode voltage was 0 V, and the final leaching rates of lithium and cobalt were >84.53% and >63.18%, respectively, with an open circuit potential of 0.84 V. Figure 8 The leaching rates of Li and Co elements in Comparative Example 2 at different working electrode potentials are shown.

[0224] Under the same testing conditions as in Example 2, the leaching rate of Li in Example 2 reached 94.84% after approximately 40 minutes, while the leaching rate of Comparative Example 2 (without UV irradiation) was 84.53% after 120 minutes. The leaching rate of Co in Example 2 reached 93.83% after approximately 40 minutes, while the leaching rate of Comparative Example 2 (without UV excitation) was 63.18% after 120 minutes.

[0225] Meanwhile, Example 2 and Comparative Example 2 demonstrate that the recovery method using nanobubbles can further improve leaching efficiency based on photoexcitation, especially by significantly increasing the leaching capacity and accelerating the leaching rate. In particular, Example 2 can achieve a leaching rate of over 90% in 30 minutes.

[0226] Example 3

[0227] An electrochemical system for recycling retired lithium-ion batteries, the electrochemical system comprising a positive electrode cavity, a negative electrode cavity, a separator, and a photoexcitation device; an acidic liquid is disposed in the positive electrode cavity; an acidic liquid is disposed in the negative electrode cavity.

[0228] The method for recycling retired lithium-ion batteries includes the following steps:

[0229] (1) Disassembly

[0230] The retired lithium-ion battery is fully discharged and then manually disassembled in a glove box filled with inert gas to obtain the positive electrode material, negative electrode material, and separator. The positive electrode material and negative electrode material are dried to allow the electrolyte and other organic solvents to evaporate.

[0231] (2) Recycling lithium, cobalt, copper, etc. from battery-like structures:

[0232] After the positive and negative electrode materials are dried, hydrochloric acid is added to the battery-like system made of the positive and negative electrode materials. The positive electrode is the retired lithium-ion battery positive electrode material, and the negative electrode is the retired lithium-ion battery negative electrode material. The separator is a battery PP (polypropylene) separator. The reaction temperature is 35℃, the reaction time is 120 min, the hydrochloric acid concentration is 2 mol / L, the working electrode potential is 0 to 0.6 V, and the positive electrode is irradiated with a 365 nm ultraviolet lamp (UV) (power 45 W). Taking a working electrode voltage of 0.2 V as an example, the reaction temperature is 35℃, the reaction time is 120 min, and the hydrochloric acid concentration is 2 mol / L. The concentration of metal ions in the leaching solution is analyzed by ICP, and the leaching rates of lithium and cobalt are calculated to be >94.11% and >91.14%, respectively, with an open circuit potential of 0.74 V. After the reaction is completed, the solid-liquid mixture is filtered to separate the solids and liquids, obtaining a metal-rich leaching solution. The working electrode voltage was adjusted, and the conditions were set as follows: hydrochloric acid concentration 2 mol / L, positive and negative electrode chamber volumes 200 ml each, stirring speed 500 rpm, reaction temperature 35℃, and working electrode voltage 0 V. ICP analysis was used to analyze the concentration of metal ions in the leaching solution, and the final leaching rates for lithium and cobalt were >95.02% and >95.95%, respectively, with an open circuit potential of 0.74 V. Furthermore, under similar conditions, adjusting the working electrode voltage to 0.4 V and 0.6 V yielded similar leaching rates for lithium and cobalt. Figure 9 The leaching rates of Li and Co elements at different working electrode potentials are shown in Example 3.

[0233] Similar technical effects can be achieved by adjusting the hydrochloric acid solution concentration to 0.2 mol / L, 0.4 mol / L, 0.8 mol / L, 1.0 mol / L, 1.2 mol / L, 1.5 mol / L, 2.5 mol / L, 3.0 mol / L, 3.5 mol / L, and 4.0 mol / L. Furthermore, high leaching rates can also be achieved simultaneously for Ni and Mn in the cathode.

[0234] Comparative Example 3

[0235] The recovery or leaching process of Comparative Example 3 was basically the same as that of Example 3, except that ultraviolet light irradiation was not used during the leaching process of the galvanic cell. The reaction temperature was 35°C, the reaction time was 120 min, the hydrochloric acid concentration was 2 mol / L, the working electrode potential was 0 to 0.6 V, the positive and negative electrode chamber volumes were 200 ml each, the stirring speed was 500 rpm, the reaction temperature was 35°C, the working electrode voltage was 0 V, and the final leaching rates of lithium and cobalt were >53.89% and >53.89%, respectively, with an open circuit potential of 0.74 V. Figure 10 The leaching rates of Li and Co elements in Comparative Example 3 at different working electrode potentials are shown.

[0236] Under the same test conditions as in Example 3, the leaching rate of Li in Example 3 reached 90.42% after approximately 60 minutes, while the leaching rate of Comparative Example 3 (without UV irradiation) was 53.89% after 120 minutes; the leaching rate of Co in Example 3 reached 90.22% after approximately 60 minutes, while the leaching rate of Comparative Example 3 (without UV irradiation) was only 53.89% after 120 minutes.

[0237] Examples 1 to 3 and Comparative Examples 1 to 3 fully demonstrate that using a primary cell structure can both recycle retired lithium-ion batteries and perform external work, and that ultraviolet irradiation can improve the leaching rate and accelerate the reaction kinetics.

[0238] Example 4

[0239] An electrochemical system for recycling retired lithium-ion batteries, the electrochemical system comprising a positive electrode cavity, a negative electrode cavity, a separator, and a photoexcitation device; an acidic liquid is disposed in the positive electrode cavity; an acidic liquid is disposed in the negative electrode cavity.

[0240] The method for recycling retired lithium-ion batteries includes the following steps:

[0241] (1) Disassembly

[0242] The retired lithium-ion battery is fully discharged and then manually disassembled in a glove box filled with inert gas to obtain the positive electrode material, negative electrode material, and separator. The positive electrode material and negative electrode material are dried to allow the electrolyte and other organic solvents to evaporate.

[0243] (2) Recycling lithium, cobalt, copper, etc. from battery-like structures:

[0244] After the positive and negative electrode materials were dried, acetic acid was added to the battery-like system made of the positive and negative electrode materials. The positive electrode was the cathode material of the retired lithium-ion battery, and the negative electrode was the anode material of the retired lithium-ion battery. The separator was a battery PP (polypropylene) separator. The conditions were set as follows: acetic acid concentration 4 mol / L, positive and negative electrode chamber volumes 400 ml each, stirring speed 600 rpm, reaction temperature 15℃, working electrode voltage 0V, and the positive electrode was irradiated with a 254 nm ultraviolet lamp (45 W power). The concentration of metal ions in the leaching solution was analyzed by ICP, and the leaching rates of lithium and cobalt were calculated to be >98.04% and >97.21%, respectively, with an open circuit potential of 0.79V. After the reaction was completed, the solid-liquid mixture was separated by filtration to obtain a metal-rich leaching solution.

[0245] Similar technical effects can be achieved by adjusting the concentration of the acetic acid solution to 1.0 mol / L, 1.2 mol / L, 1.5 mol / L, 2.5 mol / L, 3.0 mol / L, 3.5 mol / L, and 5.0 mol / L. Furthermore, high leaching rates can also be achieved simultaneously for Ni and Mn in the cathode.

[0246] Example 5

[0247] An electrochemical system for recycling retired lithium-ion batteries, the electrochemical system comprising a positive electrode cavity, a negative electrode cavity, a separator, and a photoexcitation device; an acidic liquid is disposed in the positive electrode cavity; an acidic liquid is disposed in the negative electrode cavity.

[0248] The method for recycling retired lithium-ion batteries includes the following steps:

[0249] (1) Disassembly

[0250] The retired lithium-ion battery is fully discharged and then manually disassembled in a glove box filled with inert gas to obtain the positive electrode material, negative electrode material, and separator. The positive electrode material and negative electrode material are dried to allow the electrolyte and other organic solvents to evaporate.

[0251] (2) Recycling lithium, cobalt, copper, etc. from battery-like structures:

[0252] After the positive and negative electrode materials are dried, nitric acid is added to the battery-like system made of the positive and negative electrode materials. The positive electrode is the retired lithium-ion battery positive electrode material, and the negative electrode is the retired lithium-ion battery negative electrode material. The separator is a battery PP (polypropylene) separator. The conditions are set as follows: nitric acid concentration 3 mol / L, positive and negative electrode chamber volumes 500 ml each, stirring speed 500 rpm, reaction temperature 40℃, working electrode voltage 0V, and the positive electrode is irradiated with a strong ultraviolet high-pressure mercury lamp with an effective spectral range of 350-450 nm, a main peak at 365 nm, and a power of 100 W. The concentration of metal ions in the leaching solution is analyzed by ICP, and the leaching rates of lithium and cobalt are calculated to be >98.26% and >98.07%, respectively, with an open circuit potential of 0.75 V. After the reaction is completed, the solid-liquid mixture is filtered to separate the solid and liquid components, obtaining a metal-rich leaching solution.

[0253] Similar technical effects can be achieved by adjusting the concentration of the nitric acid solution to 1.0 mol / L, 1.2 mol / L, 1.5 mol / L, 2.5 mol / L, 3.5 mol / L, 4.0 mol / L, and 4.5 mol / L. Furthermore, high leaching rates can also be achieved simultaneously for Ni and Mn in the cathode.

[0254] Example 6

[0255] An electrochemical system for recycling retired lithium-ion batteries, the electrochemical system comprising a positive electrode cavity, a negative electrode cavity, a separator, and a photoexcitation device; an acidic liquid is disposed in the positive electrode cavity; an acidic liquid is disposed in the negative electrode cavity.

[0256] The method for recycling retired lithium-ion batteries includes the following steps:

[0257] (1) Disassembly

[0258] The retired lithium-ion battery is fully discharged and then manually disassembled in a glove box filled with inert gas to obtain the positive electrode material, negative electrode material, and separator. The positive electrode material and negative electrode material are dried to allow the electrolyte and other organic solvents to evaporate.

[0259] (2) Recycling lithium, cobalt, copper, etc. from battery-like structures:

[0260] After the positive and negative electrode materials are dried, hydrochloric acid and ascorbic acid are added to a battery-like system made of the positive and negative electrode materials. The positive electrode is the cathode material of a retired lithium-ion battery, and the negative electrode is the anode material of a retired lithium-ion battery. The separator is a battery PP (polypropylene) separator. The conditions are set as follows: hydrochloric acid and ascorbic acid are mixed in a 1:1 volume ratio, with a hydrochloric acid concentration of 1 mol / L and an ascorbic acid concentration of 1 mol / L. The volumes of the positive and negative electrode chambers are 200 ml each. The stirring speed is 100 rpm, the reaction temperature is 30℃, the working electrode voltage is 0 V, and the positive electrode is irradiated with a 254 nm ultraviolet lamp (65 W power). The concentration of metal ions in the leaching solution is analyzed by ICP, and the leaching rates of lithium and cobalt are calculated to be >97.85% and >97.07%, respectively, with an open circuit potential of 0.77 V. After the reaction, the solid-liquid mixture is filtered to separate the solids and liquids, obtaining a metal-rich leaching solution. In addition, high leaching rates can also be achieved for Ni and Mn in the positive electrode.

[0261] The above description is merely a specific embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent transformations made using the present invention, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

[0262] For conditions not specifically specified in the examples, standard conditions or manufacturer-recommended conditions were followed. For reagents or instruments whose manufacturers are not specified, they are all commercially available standard products.

Claims

1. An electrochemical system for recycling batteries, characterized in that, The electrochemical system includes a positive electrode cavity, a negative electrode cavity, a diaphragm, and a photoexcitation device; An acidic liquid is provided in the positive electrode cavity, and the positive electrode of the battery to be processed is placed into the acidic liquid in the positive electrode cavity. The negative electrode cavity is filled with an acidic liquid, and the negative electrode of the battery to be processed is placed into the acidic liquid in the negative electrode cavity. The wavelength of the ultraviolet light emitted by the photoexcitation device is ≤770nm, and the power of the photoexcitation device is ≥45W; The metals recovered from the battery include lithium, cobalt, nickel, and manganese in the positive electrode and copper in the negative electrode. The electrochemical system constitutes a galvanic cell system.

2. The electrochemical system according to claim 1, characterized in that, The electrochemical system satisfies at least one of the following conditions a to h: a. The acidic liquid in the positive electrode cavity includes inorganic acid solutions and / or organic acid solutions; b. The acidic liquid in the negative electrode cavity includes inorganic acid solutions and / or organic acid solutions; c. The concentration of the acidic liquid in the positive electrode cavity is from 0.01 mol / L to 10 mol / L; d. The concentration of the acidic liquid in the negative electrode cavity is from 0.01 mol / L to 10 mol / L; e. The acidic liquid in the positive electrode cavity includes an inorganic acid solution, which includes at least one of hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, perchloric acid, hydrobromic acid, hydroiodic acid, boric acid, and carbonic acid; f. The acidic liquid in the negative electrode cavity includes an inorganic acid solution, which includes at least one of hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, perchloric acid, hydrobromic acid, hydroiodic acid, boric acid, and carbonic acid; g. The acidic liquid in the positive electrode cavity includes an organic acid solution, wherein the organic acid solution includes at least one of formic acid, acetic acid, propionic acid, butyric acid, octanoic acid, adipic acid, oxalic acid, malonic acid, succinic acid, maleic acid, tartaric acid, benzoic acid, phenylacetic acid, phthalic acid, terephthalic acid, valeric acid, hexanoic acid, decanoic acid, stearic acid, palmitic acid, acrylic acid, ascorbic acid, and malic acid; h. The acidic liquid in the negative electrode cavity includes an organic acid solution, which includes at least one of formic acid, acetic acid, propionic acid, butyric acid, octanoic acid, adipic acid, oxalic acid, malonic acid, succinic acid, maleic acid, tartaric acid, benzoic acid, phenylacetic acid, phthalic acid, terephthalic acid, valeric acid, hexanoic acid, decanoic acid, stearic acid, palmitic acid, acrylic acid, ascorbic acid, and malic acid.

3. The electrochemical system according to claim 1, characterized in that, The photoexcitation device satisfies any one of the following conditions (1) to (7): (1) The wavelength of the light emitted by the photoexcitation device is ≤400nm; (2) The wavelength of the light emitted by the photoexcitation device is from 10 nm to 400 nm; (3) The wavelength of the light emitted by the photoexcitation device is 320 nm to 400 nm; (4) The wavelength of the light emitted by the photoexcitation device is 280 nm to 320 nm; (5) The wavelength of the light emitted by the photoexcitation device is 190 nm to 280 nm; (6) The wavelength of the light emitted by the photoexcitation device is from 100 nm to 190 nm; (7) The wavelength of the light emitted by the photoexcitation device is 10 nm to 100 nm.

4. The electrochemical system according to claim 1, characterized in that, The photoexcitation device satisfies any one of the following conditions (1) to (6): (1) The power of the photoexcitation device is ≥55W; (2) The power of the photoexcitation device is ≥65W; (3) The power of the photoexcitation device is ≥75W; (4) The power of the photoexcitation device is ≥100W; (5) The power of the photoexcitation device is ≥140W; (6) The power of the photoexcitation device is ≥200W.

5. The electrochemical system according to any one of claims 1-4, characterized in that, The electrochemical system satisfies at least one of the following conditions A to K: A. The acidic liquid in the positive electrode cavity contains nanobubbles with a diameter not exceeding 1000 nm; B. The acidic liquid in the negative electrode cavity contains nanobubbles with a diameter not exceeding 1000 nm; C. The electrodes of the electrochemical system are a two-electrode system; D. The electrochemical system does not include an external power source; E. The electrochemical system includes conductive connection components; F. The batteries to be recycled include at least one of lithium-ion batteries, sodium-ion batteries, potassium-ion batteries, lithium-sulfur batteries, sodium-sulfur batteries, and potassium-sulfur batteries; G. A positive electrode cavity and a negative electrode cavity constitute a cavity combination, the electrochemical system includes one or more of the cavity combinations, and the positive electrode cavity and the negative electrode cavity are separated by a diaphragm; H. The positive and / or negative cavity is light-transmitting; I. The open-circuit potential of the electrochemical system is ≤2.5 V, and the working electrode potential of the electrochemical system is lower than the open-circuit potential of the electrochemical system; J. The diaphragm includes at least one of polyethylene diaphragm, polypropylene diaphragm, nylon diaphragm, nitrocellulose diaphragm, cellulose acetate diaphragm, polysulfone diaphragm, polyamide diaphragm, polyacrylonitrile diaphragm, polyvinyl chloride diaphragm, polytetrafluoroethylene diaphragm, polyvinylidene fluoride diaphragm, and polycarbonate diaphragm; K. The electrochemical system does not include conductive encapsulating materials.

6. A method for recycling batteries, characterized in that, The method includes the following steps: (i) Provide an electrochemical system, the electrochemical system comprising a positive electrode cavity, a negative electrode cavity, a membrane, and a photoexcitation device; An acidic liquid is provided in the positive electrode cavity; An acidic liquid is provided in the negative electrode cavity; (ii) Place the positive electrode of the battery to be treated into the acidic liquid in the positive electrode chamber; (iii) Place the negative electrode of the battery to be treated into the acidic liquid in the negative electrode cavity; (iv) Connect the positive terminal and the negative terminal of the battery to be treated; (v) Irradiate the positive electrode with light emitted by the photoexcitation device; The wavelength of the ultraviolet light emitted by the photoexcitation device is ≤770nm, and the power of the photoexcitation device is ≥45W; The metals recovered from the battery include lithium, cobalt, nickel, and manganese in the positive electrode and copper in the negative electrode. The electrochemical system constitutes a galvanic cell system.

7. The method according to claim 6, characterized in that, The electrochemical system satisfies at least one of the following conditions a to h: a. The acidic liquid in the positive electrode cavity includes inorganic acid solutions and / or organic acid solutions; b. The acidic liquid in the negative electrode cavity includes inorganic acid solutions and / or organic acid solutions; c. The concentration of the acidic liquid in the positive electrode cavity is from 0.01 mol / L to 10 mol / L; d. The concentration of the acidic liquid in the negative electrode cavity is from 0.01 mol / L to 10 mol / L; e. The acidic liquid in the positive electrode cavity includes an inorganic acid solution, which includes at least one of hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, perchloric acid, hydrobromic acid, hydroiodic acid, boric acid, and carbonic acid; f. The acidic liquid in the negative electrode cavity includes an inorganic acid solution, which includes at least one of hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, perchloric acid, hydrobromic acid, hydroiodic acid, boric acid, and carbonic acid; g. The acidic liquid in the positive electrode cavity includes an organic acid solution, wherein the organic acid solution includes at least one of formic acid, acetic acid, propionic acid, butyric acid, octanoic acid, adipic acid, oxalic acid, malonic acid, succinic acid, maleic acid, tartaric acid, benzoic acid, phenylacetic acid, phthalic acid, terephthalic acid, valeric acid, hexanoic acid, decanoic acid, stearic acid, palmitic acid, acrylic acid, ascorbic acid, and malic acid; h. The acidic liquid in the negative electrode cavity includes an organic acid solution, which includes at least one of formic acid, acetic acid, propionic acid, butyric acid, octanoic acid, adipic acid, oxalic acid, malonic acid, succinic acid, maleic acid, tartaric acid, benzoic acid, phenylacetic acid, phthalic acid, terephthalic acid, valeric acid, hexanoic acid, decanoic acid, stearic acid, palmitic acid, acrylic acid, ascorbic acid, and malic acid.

8. The method according to claim 6, characterized in that, The photoexcitation device satisfies any one of the following conditions (1) to (7): (1) The wavelength of the light emitted by the photoexcitation device is ≤400nm; (2) The wavelength of the light emitted by the photoexcitation device is from 10 nm to 400 nm; (3) The wavelength of the light emitted by the photoexcitation device is 320 nm to 400 nm; (4) The wavelength of the light emitted by the photoexcitation device is 280 nm to 320 nm; (5) The wavelength of the light emitted by the photoexcitation device is 190 nm to 280 nm; (6) The wavelength of the light emitted by the photoexcitation device is from 100 nm to 190 nm; (7) The wavelength of the light emitted by the photoexcitation device is 10 nm to 100 nm.

9. The method according to claim 6, characterized in that, The photoexcitation device satisfies any one of the following conditions (1) to (6): (1) The power of the photoexcitation device is ≥55W; (2) The power of the photoexcitation device is ≥65W; (3) The power of the photoexcitation device is ≥75W; (4) The power of the photoexcitation device is ≥100W; (5) The power of the photoexcitation device is ≥140W; (6) The power of the photoexcitation device is ≥200W.

10. The method according to any one of claims 6-9, characterized in that, The electrochemical system satisfies at least one of the following conditions A to L: A. The acidic liquid in the positive electrode cavity contains nanobubbles with a diameter not exceeding 1000 nm; B. The acidic liquid in the negative electrode cavity contains nanobubbles with a diameter not exceeding 1000 nm; C. The electrodes of the electrochemical system are a two-electrode system; D. The electrochemical system does not include an external power source; E. The electrochemical system includes conductive connection components; F. The batteries to be recycled include at least one of lithium-ion batteries, sodium-ion batteries, potassium-ion batteries, lithium-sulfur batteries, sodium-sulfur batteries, and potassium-sulfur batteries; G. A positive electrode cavity and a negative electrode cavity constitute a cavity combination, the electrochemical system includes one or more of the cavity combinations, and the positive electrode cavity and the negative electrode cavity are separated by a diaphragm; H. The positive and / or negative cavity is light-transmitting; I. The open-circuit potential of the electrochemical system is ≤2.5 V, and the working electrode potential of the electrochemical system is lower than the open-circuit potential of the electrochemical system; J. The diaphragm includes at least one of polyethylene diaphragm, polypropylene diaphragm, nylon diaphragm, nitrocellulose diaphragm, cellulose acetate diaphragm, polysulfone diaphragm, polyamide diaphragm, polyacrylonitrile diaphragm, polyvinyl chloride diaphragm, polytetrafluoroethylene diaphragm, polyvinylidene fluoride diaphragm, and polycarbonate diaphragm; K. The method does not include the processes of crushing, ultrasonically vibrating, roasting, sieving, magnetically separating, and grinding the positive and negative electrodes of the batteries to be recycled; L. The electrochemical system does not include conductive encapsulating materials.

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