A method and device for regenerating waste lithium iron phosphate material

Abstract

The present invention relates to the field of lithium-ion batteries, and in particular to a method for regenerating waste lithium iron phosphate materials, a device for regenerating waste lithium iron phosphate materials, an electronic device, and a computer-readable storage medium. The method for regenerating waste lithium iron phosphate materials comprises: pre-treating a to-be-recyclable material containing waste lithium iron phosphate materials to obtain a first recyclable material, wherein the first recyclable material comprises waste lithium iron phosphate materials; adding a regeneration liquid to the first recyclable material for reaction to obtain a second recyclable material, wherein the regeneration liquid comprises a reducing organic acid, a lithium salt, and an inorganic acid; the pH value of the regeneration liquid is 7.0±0.5; and post-treating the second recyclable material to obtain a regenerated lithium iron phosphate material. The problem of using a large amount of acid and alkali solution, low recovery efficiency, and environmental pollution in the wet regeneration process of waste lithium iron phosphate materials is solved. The present invention also provides a device for regenerating waste lithium iron phosphate materials, an electronic device, and a computer-readable storage medium.

Description

Technical Field

[0001] The present invention relates to the field of lithium-ion batteries, and in particular to a method for regenerating waste lithium iron phosphate materials, a device for regenerating waste lithium iron phosphate materials, an electronic device, and a computer-readable storage medium. Background Art

[0002] With the rapid development of the new energy electric vehicle industry, the demand for lithium iron phosphate batteries has continued to increase due to their good thermal stability, high safety and superior cycle performance, and major manufacturers have increased their production of lithium iron phosphate batteries. However, the battery life is limited, and the number of retired lithium iron phosphate batteries increases year by year. If these retired lithium iron phosphate materials cannot be effectively recycled, it will cause a serious waste of resources.

[0003] At present, the recycling of waste lithium iron phosphate positive electrode materials generally adopts the hydrometallurgical method to recycle lithium, iron, phosphorus and other elements. However, this method uses a large amount of acid and alkali, has a complex process, low recycling efficiency and high cost, poor economic benefits, and the recycling process causes great pollution to the environment. Summary of the invention

[0004] In order to solve the problems of large acid and alkali consumption, low recycling efficiency, environmental pollution, etc. in the recycling process of waste lithium iron phosphate materials, the present invention provides a waste lithium iron phosphate material regeneration method and device, electronic equipment, and computer-readable storage medium.

[0005] In a first aspect, the present invention provides a method for regenerating waste lithium iron phosphate materials, comprising:

[0006] Step S11, pre-treating the recyclable material containing waste lithium iron phosphate material to obtain a first recyclable material, wherein the first recyclable material includes the waste lithium iron phosphate material;

[0007] Step S12, adding a regeneration liquid to the first recyclable material to react to obtain a second recyclable material, wherein the regeneration liquid includes a reducing organic acid, a lithium salt, and an inorganic acid; and the pH value of the regeneration liquid is 7±0.5;

[0008] Step S13, post-processing the second recyclable material to obtain regenerated lithium iron phosphate material.

[0009] In some embodiments, the organic acid is one or more combinations of formic acid, acetic acid, propionic acid, butyric acid, caprylic acid, adipic acid, oxalic acid, malonic acid, succinic acid, maleic acid, benzoic acid, phenylacetic acid, phthalic acid, terephthalic acid, valeric acid, caproic acid, stearic acid, palmitic acid, acrylic acid, aminosulfonic acid, carboxyacetic acid, citric acid, ethylenediaminetetraacetic acid, ascorbic acid, formaldehyde, and oxalic acid.

[0010] In some embodiments, the lithium salt is one or more combinations of lithium hydroxide, lithium chloride, lithium phosphate, lithium dihydrogen phosphate, lithium carbonate, lithium acetate, and lithium nitrate.

[0011] In some embodiments, the inorganic acid is one or more of hydrochloric acid, hydrofluoric acid, and hydrobromic acid.

[0012] In some embodiments, a regeneration liquid is added to the first recyclate to react to obtain a second recyclate, wherein the weight ratio of the first recyclate to the regeneration liquid is 1:(1-8).

[0013] In some embodiments, a regeneration liquid is added to the first recyclate to react to obtain a second recyclate, wherein the reaction temperature is 30° C. to 90° C. and the reaction time is 1 h to 8 h.

[0014] In some embodiments, step S11, pre-treating the recyclable material containing waste lithium iron phosphate material to obtain a first recyclable material, includes:

[0015] Step S111, discharging the waste lithium iron phosphate battery;

[0016] Step S112, disassembling and sorting the discharged waste lithium iron phosphate batteries to obtain waste lithium iron phosphate materials to be recycled;

[0017] Step S113, subjecting the recyclable material containing waste lithium iron phosphate material to a first sintering treatment under an inert gas protection environment to obtain a first pre-treated recyclable material, wherein the first pre-treated recyclable material includes waste lithium iron phosphate material;

[0018] Step S114, performing a first screening process on the first pre-processed recyclables to obtain second pre-processed recyclables and aluminum foil, wherein the second pre-processed recyclables include waste lithium iron phosphate materials;

[0019] Step S115, crushing the second pre-processed recyclables to obtain first recyclables.

[0020] In some embodiments, the sintering temperature of the first sintering process is 300° C. to 700° C., and the sintering time is 0.5 h to 3 h.

[0021] In some embodiments, step S13, post-processing the second recyclate to obtain a regenerated lithium iron phosphate material includes:

[0022] Step S131, filtering the second recyclate to obtain a first post-processed recyclate and a filtrate;

[0023] Step S132, drying the first post-processed recyclables to obtain second post-processed recyclables;

[0024] Step S133, adding lithium carbonate powder to the second post-processed recyclate for grinding and mixing to obtain a third post-processed recyclate;

[0025] Step S134, subjecting the third post-processed recyclables to a second sintering treatment under an inert gas protection environment to obtain a fourth post-processed recyclables;

[0026] Step S135, performing a second screening process on the fourth post-processed recyclate to obtain a regenerated lithium iron phosphate material.

[0027] In some embodiments, the sintering temperature of the second sintering process is 300° C. to 800° C., and the sintering time is 1 hour to 8 hours.

[0028] In some embodiments, the inert gas is one or more of nitrogen, helium, argon, and carbon dioxide.

[0029] In a second aspect, the present invention provides a waste lithium iron phosphate material regeneration device, comprising:

[0030] A pre-treatment device, used for pre-treating the recyclable material containing waste lithium iron phosphate material to obtain a first recyclable material, wherein the first recyclable material includes the waste lithium iron phosphate material;

[0031] A reaction device, used for adding a regeneration liquid to the first recyclable material for reaction to obtain a second recyclable material, wherein the regeneration liquid comprises a reducing organic acid, a lithium salt, and an inorganic acid; and the pH value of the regeneration liquid is 7±0.5;

[0032] The post-processing device is used to post-process the second recyclable material to obtain regenerated lithium iron phosphate material.

[0033] In a third aspect, the present invention provides an electronic device, comprising: a memory for storing instructions; and a processor for calling the instructions stored in the memory to execute the method for regenerating waste lithium iron phosphate materials as described in any one of the first aspects.

[0034] In a fourth aspect, the present invention provides a computer-readable storage medium storing instructions, which, when executed by a processor, perform a method for regenerating waste lithium iron phosphate materials as described in any one of the first aspects.

[0035] In the wet regeneration process of waste lithium iron phosphate materials, a large amount of acid and alkali solutions are used, the recovery efficiency is low, and it is easy to pollute the environment. The waste lithium iron phosphate material regeneration method adopted by the present invention has the following beneficial effects:

[0036] 1. In the regeneration process of this method, the pH value of the regeneration liquid used is 7±0.5, so only a small amount of acid and alkali is needed to complete the regeneration, thereby reducing the use of acid and alkali and the resulting environmental pollution problems.

[0037] 2. During the reaction of adding the regeneration liquid to the first recyclate, the pH value of the regeneration liquid is 7±0.5, so that the regeneration liquid will not be too high in pH, which will cause the divalent iron to be easily oxidized to form trivalent iron when it comes into contact with air under alkaline conditions. At the same time, the regeneration liquid will not be too acidic due to the low pH, which will cause the dissolution of metal elements in the lithium iron phosphate material and affect the material performance, thereby achieving the purpose of improving the recovery efficiency.

[0038] 3. During the use of the battery, a solid electrolyte membrane will be formed at the interface of the electrolyte and the positive electrode material, which is mainly composed of inorganic and organic components; in addition, the first recycled material is often mixed with aluminum and other impurities during the pre-treatment process, and the inorganic acid component in the regeneration liquid has the effect of dissolving and removing impurities on the solid electrolyte membrane, aluminum and other impurities in the first recycled material, reducing the content of impurities in the material, thereby improving the purity of the regenerated lithium iron phosphate material. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 A schematic diagram of a process for regenerating waste lithium iron phosphate materials according to some embodiments is shown;

[0040] Figure 2 A schematic diagram of a process for regenerating waste lithium iron phosphate materials in some other embodiments is shown;

[0041] Figure 3 A diagram showing a waste lithium iron phosphate material regeneration device according to some embodiments;

[0042] Figure 4 A diagram showing a waste lithium iron phosphate material regeneration device in some other embodiments;

[0043] Figure 5 A schematic diagram of an electronic device is shown. DETAILED DESCRIPTION

[0044] Now the content of the present invention will be discussed with reference to several exemplary embodiments. It should be understood that these embodiments are discussed only to enable those skilled in the art to better understand and thus implement the content of the present invention, rather than implying any limitation on the scope of the present invention.

[0045] As used herein, the term "including" and variations thereof are to be interpreted as open-ended terms meaning "including but not limited to." The term "based on" is to be interpreted as "based, at least in part, on." The terms "one embodiment" and "an embodiment" are to be interpreted as "at least one embodiment." The term "another embodiment" is to be interpreted as "at least one other embodiment."

[0046] This embodiment discloses a method 10 for regenerating waste lithium iron phosphate materials. Figure 1 As shown, it may include steps S11 to S13, and the above steps are described in detail below:

[0047] Step S11, pre-treating the recyclable material containing waste lithium iron phosphate material to obtain a first recyclable material, wherein the first recyclable material includes waste lithium iron phosphate material.

[0048] In the disclosed embodiment, the recyclable material containing waste lithium iron phosphate material is pre-treated, wherein the pre-treatment may include the processing steps of discharging, disassembling, sintering, screening and crushing, and the waste lithium iron phosphate material therein may be separated, so as to facilitate the subsequent repair and regeneration of the waste lithium iron phosphate material. In this way, no acid and alkali are used in the pre-treatment process, thus reducing the problem of environmental pollution caused by acid and alkali. The recyclable material may be a positive electrode sheet containing waste lithium iron phosphate material and aluminum foil after separation of waste lithium-ion batteries.

[0049] Step S12, adding regeneration liquid to the first recyclable material for reaction to obtain a second recyclable material, wherein the regeneration liquid may include reducing organic acid, lithium salt, and inorganic acid; and the pH value of the regeneration liquid may be 7±0.5.

[0050] In the disclosed embodiment, a regeneration liquid is added to the first recyclate containing waste lithium iron phosphate material for reaction, so that the waste lithium iron phosphate material can be repaired. The reducing organic acid in the regeneration liquid can reduce the trivalent iron ions in the waste lithium iron phosphate material to divalent iron ions. And because the organic acid is easily decomposed by heat, the organic acid remaining in the repaired material will be separated from the lithium iron phosphate material during the subsequent drying treatment. The regenerated lithium iron phosphate material has a higher purity. The lithium ions in the lithium salt in the regeneration liquid can supplement the lithium ions missing in the waste lithium iron phosphate material. Since the first recyclate containing waste lithium iron phosphate material usually contains a solid electrolyte membrane and aluminum and other impurities are mixed in the pretreatment process, if the aluminum, other impurities and solid electrolyte therein are not treated, this will result in a low purity of the regenerated material and affect the performance of the regenerated material. Since the pH value of the regeneration liquid is 7±0.5, the regeneration liquid will not be easily oxidized to generate trivalent iron when the divalent iron contacts with air under alkaline conditions due to the high pH. At the same time, the pH value will not be too low, resulting in the acidity of the regeneration liquid being too strong, which will lead to the dissolution of metal elements in the lithium iron phosphate material and affect the performance of the lithium iron phosphate material after regeneration. The inorganic acid in the regeneration liquid can dissolve the solid electrolyte membrane, aluminum and other impurities in the first recyclable material, reduce the content of impurities in the material and improve the purity. In order to make the reaction conducive to the regeneration of waste lithium iron phosphate materials, the pH value of the regeneration liquid can be 7±0.5. Since the pH value of the regeneration liquid can be 7±0.5, this can also reduce the problem of environmental pollution caused by acid and alkali.

[0051] Step S13, post-processing the second recyclable material to obtain regenerated lithium iron phosphate material.

[0052] In the embodiment of the present disclosure, the second recyclate after regeneration with the regeneration liquid is subjected to post-processing, wherein the post-processing may include the steps of filtering, drying, adding lithium carbonate to grind and mix, sintering, and screening, so as to obtain regenerated lithium iron phosphate material.

[0053] In some embodiments, the organic acid can be one or more combinations of formic acid, acetic acid, propionic acid, butyric acid, caprylic acid, adipic acid, oxalic acid, malonic acid, succinic acid, maleic acid, benzoic acid, phenylacetic acid, phthalic acid, terephthalic acid, valeric acid, caproic acid, stearic acid, palmitic acid, acrylic acid, aminosulfonic acid, carboxyacetic acid, citric acid, ethylenediaminetetraacetic acid, ascorbic acid, formaldehyde, and oxalic acid.

[0054] In the disclosed embodiments, the organic acid can be one or more combinations of formic acid, acetic acid, propionic acid, butyric acid, octanoic acid, adipic acid, oxalic acid, malonic acid, succinic acid, maleic acid, benzoic acid, phenylacetic acid, phthalic acid, terephthalic acid, valeric acid, caproic acid, stearic acid, palmitic acid, acrylic acid, aminosulfonic acid, carboxyacetic acid, citric acid, ethylenediaminetetraacetic acid, ascorbic acid, formaldehyde, and oxalic acid, so that the organic acid can reduce the trivalent iron ions in the waste lithium iron phosphate material to divalent iron ions, and complete the regeneration of iron ions. In other embodiments, the organic acid can be citric acid. Citric acid has strong reducibility and the cost of citric acid is low, which can shorten the reaction time and reduce the regeneration cost. In addition, citric acid is a natural organic acid, safe and environmentally friendly, and reduces pollution to the environment.

[0055] In some embodiments, the lithium salt may be one or more combinations of lithium hydroxide, lithium chloride, lithium phosphate, lithium dihydrogen phosphate, lithium carbonate, lithium acetate, and lithium nitrate.

[0056] In the embodiments of the present disclosure, the lithium salt may be one or more combinations of lithium hydroxide, lithium chloride, lithium phosphate, lithium dihydrogen phosphate, lithium carbonate, lithium acetate, and lithium nitrate, so that the lithium salt can provide lithium ions to supplement the lithium ions missing in the waste lithium iron phosphate material. In other embodiments, the lithium salt may be lithium hydroxide. Lithium hydroxide has better solubility and can release lithium ions more easily, which can shorten the regeneration time and thus reduce the regeneration cost.

[0057] In some embodiments, the inorganic acid can be one or more combinations of hydrochloric acid, hydrofluoric acid, and hydrobromic acid.

[0058] In the disclosed embodiment, the inorganic acid may be one or more combinations of hydrochloric acid, hydrofluoric acid, and hydrobromic acid, so that the solid electrolyte membrane, aluminum, and other impurities in the first recyclate can be dissolved, thereby improving the purity of the regenerated lithium iron phosphate material. In other embodiments, the inorganic acid may be hydrochloric acid. Since hydrochloric acid has low cost, it can also better dissolve the solid electrolyte membrane, aluminum, and other impurities, thereby reducing the regeneration cost.

[0059] In some embodiments, a regeneration liquid is added to the first recyclate to react to obtain a second recyclate, wherein the weight ratio of the first recyclate to the regeneration liquid can be 1:(1-8).

[0060] In the disclosed embodiment, when the regeneration liquid is added to the first recyclate for reaction, the weight ratio of the first recyclate to the regeneration liquid can be 1: (1-8), so that the first recyclate and the regeneration liquid can be mixed, which can shorten the reaction time and reduce the repair cost. In other embodiments, the weight ratio of the first recyclate to the regeneration liquid can be 1: 4, so that the first recyclate and the regeneration liquid can be fully mixed, and the amount of the regeneration liquid can be reduced, thereby reducing the repair cost.

[0061] In some embodiments, a regeneration liquid is added to the first recyclate to react to obtain a second recyclate, wherein the reaction temperature is 30° C. to 90° C. and the reaction time is 1 h to 8 h.

[0062] In the disclosed embodiment, the regeneration liquid is added to the first recyclable material for reaction, wherein the reaction temperature is 30°C to 90°C and the reaction time is 1h to 8h, so that the regeneration liquid and the first recyclable material can be completely reacted. In other embodiments, the reaction temperature is 60°C to 80°C and the reaction time is 4h to 6h, so that the regeneration liquid and the first recyclable material can be fully reacted, and the energy consumption and reaction time can be made to reach the most reasonable state, thereby reducing the comprehensive cost of regeneration.

[0063] In some embodiments, step S11, pre-treating the recyclable material containing waste lithium iron phosphate material to obtain the first recyclable material, may include:

[0064] Step S111, discharging the waste lithium iron phosphate battery;

[0065] Step S112, disassembling and sorting the discharged waste lithium iron phosphate batteries to obtain waste lithium iron phosphate materials to be recycled;

[0066] Step S113, subjecting the recyclable material containing waste lithium iron phosphate material to a first sintering treatment under an inert gas protection environment to obtain a first pre-treated recyclable material, wherein the first pre-treated recyclable material includes waste lithium iron phosphate material;

[0067] Step S114, performing a first screening process on the first pre-processed recyclables to obtain second pre-processed recyclables and aluminum foil, wherein the second pre-processed recyclables include waste lithium iron phosphate materials;

[0068] Step S115, crushing the second pre-processed recyclables to obtain first recyclables.

[0069] In the embodiments of the present disclosure, Figure 2 As shown, the pre-treatment in step S11 may also include discharge treatment, disassembly and sorting treatment, first sintering treatment, first screening treatment and crushing treatment. Step S111, the waste lithium iron phosphate battery is discharged, so that the residual electricity in the waste lithium iron phosphate battery can be released, so that the lithium ions in the battery are embedded in the lithium iron phosphate material as much as possible, so that the concentration of the regeneration liquid can be reduced during the regeneration process, thereby reducing the recycling cost. At the same time, the waste lithium iron phosphate battery is discharged, and the combustion and explosion of the waste lithium iron phosphate battery during the disassembly and sorting treatment can be prevented, thereby ensuring the safe recycling of the waste lithium iron phosphate material during the regeneration process. Step S112, the discharged waste lithium iron phosphate battery is disassembled and sorted to obtain the recyclable material containing waste lithium iron phosphate material. By disassembling the waste lithium iron phosphate battery and sorting the positive electrode sheet in the waste battery, the waste lithium iron phosphate material can be separated from the entire waste lithium iron phosphate battery, which is convenient for the subsequent steps in the regeneration process of the waste lithium iron phosphate material. Step S113, the recyclable material containing waste lithium iron phosphate material is subjected to a first sintering treatment under an inert gas protection environment, so that the adhesive used to adhere the waste lithium iron phosphate material and the aluminum foil in the recyclable material can be carbonized, so that the waste lithium iron phosphate material and the aluminum foil are separated. At the same time, the inert gas protection can prevent the divalent iron ions in the waste lithium iron phosphate material from being oxidized into trivalent iron ions in the air, thereby reducing the cost of regeneration. Step S114, the first pre-treated recyclable material is subjected to a first screening treatment, and the first pre-treated recyclable material is separated, so that the second pre-treated recyclable material and the aluminum foil can be obtained. While separating the second pre-treated recyclable material including the waste lithium iron phosphate material, the aluminum foil can also be recovered, so as to improve the comprehensive benefits of the waste lithium iron phosphate material regeneration process. Step S115, the second pre-treated recyclable material is crushed, so that the second pre-treated recyclable material can be crushed into a powdered first recyclable material, which is convenient for the subsequent steps.

[0070] In some embodiments, the sintering temperature of the first sintering process may be 300° C. to 700° C., and the sintering time may be 0.5 h to 3 h.

[0071] In the disclosed embodiment, the sintering temperature of the first sintering treatment can be 300°C to 700°C, and the sintering time can be 0.5h to 3h, so that the adhesive used to adhere the waste lithium iron phosphate material and the aluminum foil in the recyclable material can be carbonized. In other embodiments, the sintering temperature of the first sintering treatment can be 400°C to 600°C, and the sintering time can be 1h to 2h, so that the carbonization of the adhesive can be completed at a suitable sintering temperature and in a shorter time, so that the energy consumption and sintering time reach the most reasonable state, thereby reducing the comprehensive cost of regeneration.

[0072] In some embodiments, step S13, post-processing the second recyclate to obtain a regenerated lithium iron phosphate material, may include:

[0073] Step S131, filtering the second recyclate to obtain a first post-processed recyclate and a filtrate;

[0074] Step S132, drying the first post-processed recyclables to obtain second post-processed recyclables;

[0075] Step S133, adding lithium carbonate powder to the second post-processed recyclate for grinding and mixing to obtain a third post-processed recyclate;

[0076] Step S134, subjecting the third post-processed recyclables to a second sintering treatment under an inert gas protection environment to obtain a fourth post-processed recyclables;

[0077] Step S135, performing a second screening process on the fourth post-processed recyclate to obtain a regenerated lithium iron phosphate material.

[0078] In the embodiments of the present disclosure, Figure 2As shown, the post-processing of step S13 may also include filtering, drying, adding lithium carbonate powder for grinding and mixing, second sintering, and second screening. Step S131, filtering the second recyclate, so that the impurities dissolved in the regeneration liquid can be separated from the second recyclate, and the first post-processing recyclate and the filtrate are obtained. Since the pH value of the regeneration liquid is 7±0.5, there is very little acid or alkali in the obtained filtrate, which reduces the pollution of the acid or alkali to the environment. Step S132, drying the first post-processing recyclate, so that the first post-processing recyclate can be converted into a dry powdered second post-processing recyclate. Step S133, in the process of adding lithium carbonate powder to the second post-processing recyclate for grinding and mixing, the dry powdered second post-processing recyclate is easier to be evenly mixed with the lithium carbonate powder. Since the second post-processing recyclate is ground and mixed with lithium carbonate, the second sintering treatment in step S134 under the inert gas protection environment can make the crystal form of the sintered lithium iron phosphate material more perfect. Inert gas protection can prevent the divalent iron ions in the waste lithium iron phosphate material from being oxidized into trivalent iron ions by oxygen in the air, thereby improving the performance of the regenerated lithium iron phosphate material. Step S135, the fourth post-processed recyclate is subjected to a second screening process, so that lithium iron phosphate material powder with uniform size can be obtained, so that the various indicators of the final regenerated lithium iron phosphate material are close to those of commercial materials.

[0079] In some embodiments, the sintering temperature of the second sintering process may be 300° C. to 800° C., and the sintering time may be 1 hour to 8 hours.

[0080] In the disclosed embodiment, the sintering temperature of the second sintering treatment can be 300°C to 800°C, and the sintering time can be 1h to 8h, so that the crystal structure of the lithium iron phosphate material can be stabilized. In other embodiments, the sintering temperature of the second sintering treatment can be 550°C to 750°C, and the sintering time can be 3h to 5h, so that the crystal structure of the lithium iron phosphate material can be stabilized while making the energy consumption and sintering time reach the most reasonable state, thereby reducing the comprehensive cost of regeneration.

[0081] In some embodiments, the inert gas may be one or more of nitrogen, helium, argon, and carbon dioxide.

[0082] In the disclosed embodiment, the inert gas may be one or more combinations of nitrogen, helium, argon, and carbon dioxide. The inert gas protection may prevent the divalent iron ions in the waste lithium iron phosphate material from being oxidized to trivalent iron ions by oxygen in the air, thereby reducing the regeneration cost and improving the performance of the regenerated lithium iron phosphate material. In other embodiments, the inert gas may be nitrogen. Since nitrogen is low in cost and easy to obtain, the cost of regeneration is reduced.

[0083] This embodiment discloses a method for regenerating waste lithium iron phosphate material. The steps are as follows:

[0084] After the waste lithium iron phosphate battery is discharged, disassembled and sorted, a dried positive electrode sheet is obtained. 12.6g of the positive electrode sheet is first sintered at 560°C for 1.5h in a nitrogen atmosphere to remove the binder, and then 12g of waste lithium iron phosphate material powder is obtained after the first screening and crushing. 12g of waste lithium iron phosphate material powder is placed in a reaction device, and 64ml of regeneration liquid is added. The regeneration liquid is an aqueous solution containing citric acid, lithium hydroxide and an appropriate amount of hydrochloric acid with a pH of 7. After adding, it is reacted at 80°C under normal pressure for 5h. After the reaction is completed, the product is filtered and dried, and mixed with 4% mol lithium carbonate (weight 0.225g) and ground and mixed. After the second sintering at 700°C for 5h in a nitrogen atmosphere, it is cooled and screened to obtain the regenerated lithium iron phosphate material positive electrode material. The regenerated lithium iron phosphate positive electrode material was assembled into a button battery. The discharge capacity in the first week at a rate of 0.1C was 145.3mAh / g, and the capacity retention rate was 98.1% after 200 cycles at 1C.

[0085] Based on the same inventive concept, the present disclosure also provides a waste lithium iron phosphate material regeneration device 20 for regenerating waste lithium iron phosphate materials, such as Figure 3 As shown, it may include:

[0086] A pre-treatment device 21 is used to pre-treat the recyclable material containing waste lithium iron phosphate material to obtain a first recyclable material, wherein the first recyclable material includes the waste lithium iron phosphate material;

[0087] The reaction device 22 is used to add the regeneration liquid to the first recyclable material to react and obtain the second recyclable material, wherein the regeneration liquid includes a reducing organic acid, a lithium salt, and an inorganic acid; the pH value of the regeneration liquid is 7±0.5;

[0088] The post-processing device 23 is used to post-process the second recyclable material to obtain regenerated lithium iron phosphate material.

[0089] In the embodiment of the present disclosure, the waste lithium iron phosphate material regeneration device may include a pre-treatment device 21, a reaction device 22, and a post-treatment device 23. The pre-treatment device 21 is used to pre-treat the waste lithium iron phosphate material to be recycled, and separate the waste lithium iron phosphate material therein, so as to facilitate the subsequent regeneration of the waste lithium iron phosphate material. Figure 4, the pre-treatment device 21 may also include a discharge device 211, a disassembly and sorting device 212, a first sintering device 213, a first screening device 214, and a crushing device 215. The discharge device 211 is used to discharge the waste lithium iron phosphate battery. The disassembly and sorting device 212 is used to disassemble and sort the discharged waste lithium iron phosphate battery to obtain the waste lithium iron phosphate material to be recycled. The first sintering device 213 is used to perform a first sintering treatment on the recyclable material containing waste lithium iron phosphate material under an inert gas protection environment to obtain a first pre-treatment recyclate, wherein the first pre-treatment recyclate includes waste lithium iron phosphate material. The first screening device 214 is used to perform a first screening treatment on the first pre-treatment recyclate to obtain a second pre-treatment recyclate and aluminum foil, wherein the second pre-treatment recyclate includes waste lithium iron phosphate material. The crushing device 215 is used to crush the second pre-treatment recyclate to obtain the first recyclate. In this way, the second pre-treatment recyclate can be crushed into a powdery first recyclate, which is convenient for the subsequent steps.

[0090] The reaction device 22 is used to add the regeneration liquid to the first recyclable material for reaction to obtain the second recyclable material, wherein the regeneration liquid includes reducing organic acid, lithium salt, and inorganic acid; the pH value of the regeneration liquid is 7±0.5. In this way, the waste lithium iron phosphate material can be regenerated.

[0091] The post-processing device 23 is used to post-process the second recyclable material to obtain a regenerated lithium iron phosphate material. In this way, a regenerated lithium iron phosphate material can be obtained. Figure 4 As shown, the post-processing device may also include a filtering device 231, a drying device 232, a grinding and mixing device 233, a second sintering device 234, and a second screening device 235. The filtering device 231 is used to filter the second recyclate to obtain the first post-processing recyclate and the filtrate. The drying device 232 is used to dry the first post-processing recyclate to obtain the second post-processing recyclate. The grinding and mixing device 233 is used to add lithium carbonate powder to the second post-processing recyclate for grinding and mixing to obtain the third post-processing recyclate. The second sintering device 234 is used to perform a second sintering treatment on the third post-processing recyclate under an inert gas protection environment to obtain a fourth post-processing recyclate. The second screening device 235 is used to perform a second screening treatment on the fourth post-processing recyclate to obtain a regenerated lithium iron phosphate material.

[0092] like Figure 5As shown, an embodiment of the present disclosure provides an electronic device 400. The electronic device 400 includes a memory 401, a processor 402, and an input / output (I / O) interface 403. The memory 401 is used to store instructions. The processor 402 is used to call the instructions stored in the memory 401 to execute the waste lithium iron phosphate material regeneration method of the embodiment of the present disclosure. The processor 402 is connected to the memory 401 and the I / O interface 403, respectively, for example, through a bus system and / or other forms of connection mechanisms (not shown). The memory 401 can be used to store programs and data, including the program of the waste lithium iron phosphate material regeneration method involved in the embodiment of the present disclosure, and the processor 402 executes various functional applications and data processing of the electronic device 400 by running the program stored in the memory 401.

[0093] In the embodiment of the present disclosure, the processor 402 can be implemented in at least one hardware form of a digital signal processor (Digital Signal Processing, DSP), a field programmable gate array (Field-Programmable Gate Array, FPGA), and a programmable logic array (Programmable Logic Array, PLA). The processor 402 can be a central processing unit (Central Processing Unit, CPU) or one or a combination of other forms of processing units with data processing capabilities and / or instruction execution capabilities.

[0094] The memory 401 in the embodiment of the present disclosure may include one or more computer program products, and the computer program product may include various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. Volatile memory may include, for example, random access memory (RAM) and / or cache memory (cache), etc. Non-volatile memory may include, for example, read-only memory (ROM), flash memory, hard disk drive (HDD), or solid-state drive (SSD), etc.

[0095] In the embodiment of the present disclosure, the I / O interface 403 may be used to receive input instructions (such as digital or character information, and key signal input related to user settings and function control of the electronic device 400), and may also output various information to the outside (such as images or sounds). In the embodiment of the present disclosure, the I / O interface 403 may include one or more of a physical keyboard, a function key (such as a volume control key, a switch key, etc.), a mouse, a joystick, a trackball, a microphone, a speaker, and a touch panel.

[0096] It is to be understood that, although the operations are described in a specific order in the drawings in the embodiments of the present disclosure, it should not be understood as requiring the operations to be performed in the specific order shown or in a serial order, or requiring the execution of all the operations shown to obtain the desired results. In certain environments, multitasking and parallel processing may be advantageous.

[0097] The methods and devices involved in the embodiments of the present disclosure can be implemented using standard programming techniques, using rule-based logic or other logic to implement various method steps. It should also be noted that the words "device" and "module" used herein and in the claims are intended to include implementations using one or more lines of software code and / or hardware implementations and / or devices for receiving input.

[0098] Any steps, operations or procedures described herein may be performed or implemented using one or more hardware or software modules, either alone or in combination with other devices. In one embodiment, the software module is implemented using a computer program product including a computer-readable medium containing computer program code, which can be executed by a computer processor to perform any or all of the described steps, operations or procedures.

[0099] The foregoing description of the implementation of the present disclosure has been given for the purpose of illustration and description. The foregoing description is not exhaustive nor is it intended to limit the present disclosure to the exact form disclosed, and various variations and modifications may exist in accordance with the above teachings or may be obtained from the practice of the present disclosure. These embodiments are selected and described in order to illustrate the principles of the present disclosure and its practical application, so that those skilled in the art can utilize the present disclosure in various embodiments and various modifications suitable for the specific purpose contemplated.

Claims

1. A method for regenerating waste lithium iron phosphate materials, characterized in that: The waste lithium iron phosphate material regeneration method comprises: Step S11, pre-treating the recyclable material containing waste lithium iron phosphate material to obtain a first recyclable material, wherein the first recyclable material includes waste lithium iron phosphate material; The pre-treatment includes: Step S111, discharging the waste lithium iron phosphate battery; Step S112, disassembling and sorting the discharged waste lithium iron phosphate batteries to obtain waste lithium iron phosphate materials to be recycled; Step S113, subjecting the to-be-recyclable material containing waste lithium iron phosphate material to a first sintering treatment under an inert gas protection environment to obtain a first pre-treated recyclable material, wherein the first pre-treated recyclable material includes waste lithium iron phosphate material; Step S114, performing a first screening process on the first pre-processed recyclables to obtain second pre-processed recyclables and aluminum foil, wherein the second pre-processed recyclables include waste lithium iron phosphate materials; Step S115, crushing the second pre-processed recyclables to obtain the first recyclables; Step S12, adding a regeneration liquid to the first recyclable material to react to obtain a second recyclable material, wherein the regeneration liquid includes a reducing organic acid, a lithium salt, and an inorganic acid; the pH value of the regeneration liquid is 7±0.5; and the inorganic acid is one or more combinations of hydrochloric acid, hydrofluoric acid, and hydrobromic acid; Step S13, post-processing the second recyclable material to obtain a regenerated lithium iron phosphate material; The post-processing includes: Step S131, filtering the second recyclate to obtain a first post-processed recyclate and a filtrate; Step S132, drying the first post-processed recyclables to obtain second post-processed recyclables; Step S133, adding lithium carbonate powder to the second post-processed recyclate for grinding and mixing to obtain a third post-processed recyclate; Step S134, subjecting the third post-processed recyclables to a second sintering treatment under an inert gas protection environment to obtain a fourth post-processed recyclables; Step S135, performing a second screening process on the fourth post-processing recyclate to obtain the regenerated lithium iron phosphate material.

2. A method for regenerating waste lithium iron phosphate materials according to claim 1, characterized in that: The organic acid is one or more combinations of formic acid, acetic acid, propionic acid, butyric acid, caprylic acid, adipic acid, oxalic acid, malonic acid, succinic acid, maleic acid, benzoic acid, phenylacetic acid, phthalic acid, terephthalic acid, valeric acid, caproic acid, stearic acid, palmitic acid, acrylic acid, aminosulfonic acid, carboxyacetic acid, citric acid, ethylenediaminetetraacetic acid, ascorbic acid, formaldehyde, and oxalic acid.

3. The method for regenerating waste lithium iron phosphate materials according to claim 1, characterized in that: The lithium salt is one or more combinations of lithium hydroxide, lithium chloride, lithium phosphate, lithium dihydrogen phosphate, lithium carbonate, lithium acetate, and lithium nitrate.

4. The method for regenerating waste lithium iron phosphate materials according to claim 1, characterized in that: The regeneration liquid is added to the first recyclable material for reaction to obtain the second recyclable material, wherein the weight ratio of the first recyclable material to the regeneration liquid is 1:(1-8).

5. The method for regenerating waste lithium iron phosphate materials according to claim 1, characterized in that: The regeneration liquid is added to the first recovered product to react to obtain the second recovered product, wherein the reaction temperature is 30° C. to 90° C. and the reaction time is 1 h to 8 h.

6. The method for regenerating waste lithium iron phosphate materials according to claim 1, characterized in that: The sintering temperature of the first sintering treatment is 300° C. to 700° C., and the sintering time is 0.5 h to 3 h.

7. The method for regenerating waste lithium iron phosphate materials according to claim 1, characterized in that: The step S13, post-processing the second recyclable material to obtain the regenerated lithium iron phosphate material, comprises: Step S131, filtering the second recyclate to obtain a first post-processed recyclate and a filtrate; Step S132, drying the first post-processed recyclables to obtain second post-processed recyclables; Step S133, adding lithium carbonate powder to the second post-processed recyclate for grinding and mixing to obtain a third post-processed recyclate; Step S134, subjecting the third post-processed recyclables to a second sintering treatment under an inert gas protection environment to obtain a fourth post-processed recyclables; Step S135, performing a second screening process on the fourth post-processing recyclate to obtain the regenerated lithium iron phosphate material.

8. A method for regenerating waste lithium iron phosphate materials according to claim 7, characterized in that: The sintering temperature of the second sintering treatment is 300° C. to 800° C., and the sintering time is 1 hour to 8 hours.

9. A method for regenerating waste lithium iron phosphate materials according to any one of claims 1 to 8, characterized in that: The inert gas is one or more of nitrogen, helium, argon and carbon dioxide.

10. A waste lithium iron phosphate material regeneration device, characterized in that: The waste lithium iron phosphate material regeneration device comprises: A pre-treatment device, used for pre-treating the recyclable material containing waste lithium iron phosphate material to obtain a first recyclable material, wherein the first recyclable material includes the waste lithium iron phosphate material; A reaction device, used for adding a regeneration liquid to the first recyclable material for reaction to obtain a second recyclable material, wherein the regeneration liquid comprises a reducing organic acid, a lithium salt, and an inorganic acid; the pH value of the regeneration liquid is 7±0.5; and the inorganic acid is one or more combinations of hydrochloric acid, hydrofluoric acid, and hydrobromic acid; A post-processing device, used for post-processing the second recyclable material to obtain a regenerated lithium iron phosphate material; The pre-treatment includes: Step S111, discharging the waste lithium iron phosphate battery; Step S112, disassembling and sorting the discharged waste lithium iron phosphate batteries to obtain waste lithium iron phosphate materials to be recycled; Step S113, subjecting the to-be-recyclable material containing waste lithium iron phosphate material to a first sintering treatment under an inert gas protection environment to obtain a first pre-treated recyclable material, wherein the first pre-treated recyclable material includes waste lithium iron phosphate material; Step S114, performing a first screening process on the first pre-processed recyclables to obtain second pre-processed recyclables and aluminum foil, wherein the second pre-processed recyclables include waste lithium iron phosphate materials; Step S115, crushing the second pre-processed recyclables to obtain the first recyclables; The post-processing includes: Step S131, filtering the second recyclate to obtain a first post-processed recyclate and a filtrate; Step S132, drying the first post-processed recyclables to obtain second post-processed recyclables; Step S133, adding lithium carbonate powder to the second post-processed recyclate for grinding and mixing to obtain a third post-processed recyclate; Step S134, subjecting the third post-processed recyclables to a second sintering treatment under an inert gas protection environment to obtain a fourth post-processed recyclables; Step S135, performing a second screening process on the fourth post-processing recyclate to obtain the regenerated lithium iron phosphate material.

11. An electronic device, characterized in that: include: A memory for storing instructions; and a processor, configured to call the instructions stored in the memory to execute the method for regenerating waste lithium iron phosphate materials as claimed in any one of claims 1 to 9.

12. A computer-readable storage medium, characterized in that: Instructions are stored, and when the instructions are executed by the processor, the method for regenerating waste lithium iron phosphate materials according to any one of claims 1 to 9 is executed.

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