Electrolytic method for valuable metal ions in waste lithium battery powder

Abstract

The present disclosure provides an electrolytic method for valuable metal ions in waste lithium battery powder, comprising the following steps: obtaining n different types of waste positive electrode battery powder, wherein n is greater than or equal to 2, and n is a positive integer; classifying the n types of waste positive electrode battery powder to separately obtain anode treatment mixed powder and cathode treatment mixed powder; separately carrying out slurry preparation operation on the anode treatment mixed powder and the cathode treatment mixed powder to obtain an anode slurry and a cathode slurry; carrying out ionization operation on the anode slurry and the cathode slurry by means of an electrolytic device; and filtering the cathode slurry that has undergone the ionization operation to obtain a cathode post-electrolysis liquid, i.e., a valuable metal ion solution. Efficient and comprehensive ionization recovery of valuable metal ions in two or more types of waste positive electrode powder is achieved, and the operation is simple and environmentally-friendly.

Description

Method for electrolyzing valuable metal ions in waste lithium battery powder Technical Field

[0001] The present disclosure relates to a method for electrolyzing valuable metal ions in waste lithium battery powder. Background Art

[0002] With the widespread adoption of new energy vehicles, the amount of waste lithium batteries generated is increasing. The typical method for processing waste lithium batteries is to first screen out batteries with a remaining capacity of 70%-80% of their initial capacity. These batteries are then reused as electrical energy carriers to avoid waste. Used lithium batteries with lower remaining capacity are then disassembled and recycled to effectively recover valuable metal ions such as nickel, cobalt, manganese, and lithium ions from the battery powder, effectively alleviating the domestic shortage of these valuable metals.

[0003] Currently, waste lithium batteries are mostly recycled using dry or wet methods. Wet recycling, currently the mainstream method, primarily involves leaching battery powder with chemical reagents, followed by separation and removal to effectively extract the nickel, cobalt, manganese, and lithium ions present. However, wet recycling suffers from low leaching efficiency, long reaction cycles, and environmental concerns. Consequently, a new recycling method has emerged: electrolysis.

[0004] For example, Chinese patent number CN116479448A discloses a recycling device and method for waste lithium iron phosphate battery positive electrode materials. The method primarily involves soaking and filtering the disassembled lithium iron phosphate positive electrode material powder in an organic solvent to obtain a lithium-containing positive electrode material powder. The lithium-containing positive electrode material powder and anolyte are then poured into the anode region of an electrolytic cell, where an electrolytic reaction is conducted through an oxygenating tube to achieve efficient ionization of the waste lithium iron phosphate material. This method not only achieves high ionization efficiency and a short reaction time, but is also environmentally friendly. However, because traditional electrolytic recycling methods can only ionize and decompose a single type of waste positive electrode powder, and cannot simultaneously ionize and decompose two or more types of waste positive electrode powder, the waste positive electrode powder ionization efficiency is relatively low.

[0005] Summary of the Invention

[0006] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a method for electrolyzing valuable metal ions in waste lithium battery powder by ionizing and recovering valuable metal ions in two or more waste positive electrode powders in an efficient and comprehensive manner, which is simple to operate and environmentally friendly.

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

[0008] A method for electrolyzing valuable metal ions in waste lithium battery powder comprises the following steps:

[0009] Obtain n different types of waste positive battery powder, where n ≥ 2 and n is a positive integer;

[0010] Classifying the n types of waste positive battery powders according to the redox properties of different valuable metals to obtain anode treatment mixed powders and cathode treatment mixed powders;

[0011] Performing slurrying operations on the anode treatment mixed powder and the cathode treatment mixed powder respectively to obtain anode slurry and cathode slurry;

[0012] performing an ionization operation on the anode slurry and the cathode slurry by an electrolysis device;

[0013] The cathode slurry after the ionization operation is filtered to obtain a cathode electrolysis liquid; wherein the cathode electrolysis liquid is a valuable metal ion solution.

[0014] The details of one or more embodiments of the invention are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the invention will become apparent from the description, drawings, and claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0016] FIG1 is a flow chart of a method for electrolyzing valuable metal ions in waste lithium battery powder according to one embodiment of the present invention;

[0017] FIG2 is a schematic structural diagram of an electrolysis device according to one embodiment of the present invention;

[0018] FIG3 is a diagram showing ion flow of anode slurry and cathode slurry during ionization according to an embodiment of the present invention.

[0019] Figure numerals: 10, electrolysis device; 100, electrolytic cell; 200, power supply; 310, anode basket; 320, anode plate; 410, cathode basket; 420, cathode plate; 510, fan; 520, anode connecting pipe; 530, cathode connecting pipe; 540, aeration plate; 541, aeration hole; 550, bending portion; 610, electrolyte feed pipe; 620, anode slurry feed pipe; 630, cathode feed pipe; 710, electrolyte discharge pipe; 720, anode slurry discharge pipe; 730, cathode discharge pipe; 800, agitator. Specific embodiments

[0020] To facilitate understanding of the present invention, the present invention will be described more fully below with reference to the accompanying drawings. Preferred embodiments of the present invention are shown in the accompanying drawings. However, the present invention may be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and comprehensive understanding of the present disclosure.

[0021] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly attached to the other element or there may be an intermediate element. When an element is referred to as being "connected to" another element, it may be directly connected to the other element or there may be an intermediate element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only embodiments.

[0022] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one skilled in the art to which this invention pertains. The terms used in this specification of the present invention are for the purpose of describing specific embodiments only and are not intended to limit the present invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0023] Referring to FIG1 , the present disclosure provides a method for electrolyzing valuable metal ions in waste lithium battery powder. To better understand the method for electrolyzing valuable metal ions in waste lithium battery powder, the following further explains the method:

[0024] The method for electrolyzing valuable metal ions in waste lithium battery powder according to one embodiment comprises the following steps:

[0025] S100: Obtain n different types of waste positive battery powder, where n ≥ 2 and n is a positive integer. It is understood that n different types of waste lithium batteries, such as waste lithium iron phosphate batteries, waste lithium cobalt oxide batteries, waste lithium manganese oxide batteries, waste lithium nickel manganese oxide / lithium nickel cobalt oxide batteries, waste lithium nickel cobalt manganese oxide batteries, and waste lithium nickel cobalt aluminum oxide batteries, are obtained by disassembling different types of waste positive electrode sheets. These n types of waste positive electrode sheets are then crushed and screened to obtain n different types of waste positive battery powder for future use.

[0026] S200, classifying n types of waste positive battery powders according to the redox properties of different valuable metals to obtain anode treatment mixed powder and cathode treatment mixed powder respectively.

[0027] It can be understood that because the valuable metal components in different types of waste positive battery powders are different, users can classify them according to the redox properties of different valuable metals in n types of waste positive battery powders, so that a variety of waste positive battery powders with strong reducing properties are used as a group of mixed powders for anode treatment; and a variety of waste positive battery powders with strong oxidizing properties are used as a group of mixed powders for cathode treatment, to ensure that the subsequent preparation of anode slurry and cathode slurry can undergo ionization reactions at the same time.

[0028] S300, performing slurrying operations on the anode treatment mixed powder and the cathode treatment mixed powder respectively to obtain anode slurry and cathode slurry.

[0029] It is understandable that since waste positive battery powder is in the form of powder particles, directly pouring it into the electrolytic cell can easily cause the powder to fly and cause loss, and the powder particles are not conducive to extraction. Therefore, in the present disclosure, by slurrying the anode treatment mixed powder and the cathode treatment mixed powder separately, the resulting anode slurry and cathode slurry are not only easier to extract and pump into the anode basket and cathode basket, but also ensure that the anode treatment mixed powder and the cathode treatment mixed powder can fully enter the electrolytic cell, thereby improving the recovery rate of the valuable metal ions in the anode treatment mixed powder and the cathode treatment mixed powder, and ensuring the normal operation of the ionization operation.

[0030] S400: performing an ionization operation on the anode slurry and the cathode slurry through an electrolysis device.

[0031] It can be understood that when the anode slurry and the cathode slurry are ionized, the valuable metal ions in the anode slurry can be electrolyzed and released in the anode slurry, thereby achieving the ionization of the valuable metal ions in the anode slurry, and a small amount of water in the anode slurry can be ionized to produce H + , the electrolyte will ionize the hydrogen ions, and at the same time, under the action of the electric field, the anode slurry will ionize the valuable metal ions, H + The hydrogen ions generated by the electrolyte can migrate to the cathode slurry under the action of the electric field, and the cathode treatment mixed powder in the cathode slurry can react with the hydrogen ions, so that the high-valent valuable metal ions in the cathode slurry can be reduced to easily soluble low-valent metal ions, thereby realizing the ionization of the valuable metal ions in the cathode slurry, so that the valuable metal ions in the anode slurry and the valuable metal ions in the cathode slurry can be enriched in the cathode slurry, that is, the valuable metal ions in the anode slurry and the cathode slurry are efficiently and comprehensively ionized at the same time, realizing the simultaneous ionization operation of two or more different types of waste lithium battery powder.

[0032] Please refer to Figure 3. In order to facilitate the understanding of the ionization principle of the anode slurry and cathode slurry disclosed in the present invention, the specific ionization principle is described below. The anode treatment mixed powder is a mixed powder of LiFePO4 and LiFeMn(PO4)2, and the cathode treatment mixed powder is LiNi X YKMv1-X-Y Mixed powder of O2, LiCoO2 and LiMn2O4, the electrolyte is dilute sulfuric acid:

[0033] The reactions occurring in the anode slurry are:

[0034] LiFePO4-e - =Li + +FePO4;

[0035] LiFeMn(PO4)2-2e - =2Li + +FePO4+MnPO4;

[0036] 2H2O-4e - =4H + +O2;

[0037] The reaction of the electrolyte is:

[0038] H2SO4=2H + +SO4 - ;

[0039] It should be noted that when the anode slurry is a mixture of LiFePO4 and LiFeMn(PO4)2, since the reducing property of LiFePO4 is stronger than that of LiFeMn(PO4)2, LiFePO4 is ionized first, and then LiFeMn(PO4)2 is ionized, and the water in the anode slurry is also partially electrolyzed to produce H + , and the electrolyte will ionize hydrogen ions under the action of the electric field, and at the same time, the anode slurry will ionize Li + 、H + and H generated by electrolyte ionization + Will migrate to the cathode slurry, so that the H generated by the electrolyte + It can realize the conduction of valuable metal ions between the anode slurry and the cathode slurry.

[0040] The reaction occurring in the cathode slurry is:

[0041] LiNi X Co Y Mn 1-X-Y O2+4H + +e - =Li + +XNi 2+ +YCo 2+ +(1-XY)Mn 2+ +2H2O;

[0042] LiCoO2+4H + +e -=Li + +Co 2+ +2H2O;

[0043] LiMn2O4+8H + +e - =Li + +2Mn 2+ +4H2O;

[0044] O2+4H + +2e - =2H2O.

[0045] It should be noted that when the cathode treatment mixed powder is LiNi X YKMv 1-X-Y When the mixed powder of O2, LiCoO2 and LiMn2O4 is used, the Li generated by the ionization of the anode slurry + 、H + , H generated by electrolyte ionization + When migrating to the cathode slurry, the order of oxidation of the three is: LiNi X Co Y Mn 1-X-Y O2>LiCoO2>LiMn2O4, so LiNi X Co Y Mn 1-X-Y O2 first reacts with H + The reaction occurs, so that the high-valent Li, Ni, Co and Mn can be reduced to low-valent valuable metal ions and free in the cathode slurry. X Co Y Mn 1-X-Y After the O2 reaction is complete, LiCoO2 will enter the reaction, and finally LiMn2O4, to achieve the ionization recovery of the cathode slurry; at the same time, the Li migrated from the anode slurry + It will be concentrated in the cathode slurry.

[0046] It should also be noted that when the cathode slurry is continuously aerated, the oxygen provided to the cathode slurry ensures that the cathode treatment mixed powder can undergo a rapid and comprehensive redox reaction to ensure efficient and comprehensive ionization of the cathode slurry.

[0047] S500, filtering the cathode slurry after the ionization operation to obtain cathode electrolysis liquid; wherein the cathode electrolysis liquid is a valuable metal ion solution.

[0048] It can be understood that the cathode slurry after the ionization operation is filtered to achieve separation of the liquid and slag in the cathode slurry, so that all the valuable metal ions in the cathode slurry can be free in the cathode electrolysis liquid, and the valuable metal ions ionized from the anode slurry will also be enriched in the cathode slurry, that is, to achieve efficient ionization of the valuable metal ions of various types of waste lithium battery powder in the anode slurry and the cathode slurry.

[0049] It should be noted that some electrolytic methods are currently used to recover valuable metals from waste lithium battery powder, such as the method for recovering metals from waste lithium battery positive electrode materials disclosed in Chinese Patent No. CN112251776B, and the device and method for recovering waste lithium iron phosphate battery positive electrode materials disclosed in Chinese Patent No. CN116479448A. However, these electrolytic methods can only process a single type of metal and are unable to efficiently process more than two types. In order to find efficient methods for recovering valuable metals from waste lithium battery powder, some scholars have developed methods such as the method for recovering valuable metals from waste batteries disclosed in Chinese Patent No. CN115109936B. While this method can achieve a coordinated leaching treatment of waste lithium iron phosphate battery positive electrode powder and waste ternary lithium battery positive electrode powder, the chemical treatment method employed is subject to harsh conditions, complex procedures, and a low leaching rate of valuable metal ions.

[0050] In order to find an efficient method for processing and recovering valuable metals in waste lithium battery powder, the present invention first obtains n different types of waste positive battery powder, and then classifies them according to the redox properties of different valuable metals in the n types of waste positive battery powder. The waste positive battery powders with strong reducing properties are divided into a group of mixed powders for anode treatment, and the waste positive battery powders with strong oxidizing properties are divided into a group of mixed powders for cathode treatment. Then, they are made into anode slurry and cathode slurry, and the anode slurry and cathode slurry are ionized by an electrolysis device, so that the valuable metal ions in the anode slurry can be electrolyzed and released in the anode slurry, and a small amount of water in the anode slurry can be ionized to produce H + , the electrolyte will ionize the hydrogen ions, and at the same time, under the action of the electric field, the anode slurry will ionize the valuable metal ions, H +The hydrogen ions generated by the electrolyte can migrate to the cathode slurry under the action of the electric field. The cathode treatment mixed powder in the cathode slurry can react with the hydrogen ions, reducing the high-valent valuable metal ions in the cathode slurry to easily soluble low-valent metal ions. This achieves the ionization of the valuable metal ions in the cathode slurry, allowing the valuable metal ions in the anode slurry and the valuable metal ions in the cathode slurry to be enriched in the cathode slurry. This allows the simultaneous ionization of multiple different types of waste lithium battery powder in the anode and cathode slurries. This is not only simple to operate and has high ionization efficiency, but also does not require the addition of additional chemical reagents, effectively ensuring the purity of the valuable metal ions, while being low-cost and environmentally friendly. It is particularly suitable for applications where multiple different types of waste battery positive electrode powder are doped during the crushing process.

[0051] In one embodiment, in the steps of slurrying the anodic treatment mixed powder and the cathodic treatment mixed powder respectively, the usage ratio of the anodic treatment mixed powder and the cathodic treatment mixed powder is the ratio of the number of electrons gained and lost between the two.

[0052] In order to ensure electron conservation throughout the entire ionization process, in the present disclosure, the ratio is determined based on the amount of electron gain and loss in the anode treatment mixed powder and the cathode treatment mixed powder to ensure that the valuable metal ions in the anode slurry and the cathode slurry can be fully ionized, thereby improving the ionization efficiency of the valuable metals in the anode slurry and the cathode slurry.

[0053] In one embodiment, the steps of slurrying the anode treatment mixed powder and the cathode treatment mixed powder respectively include the following specific steps: mixing the anode treatment mixed powder and water in a certain proportion to obtain anode slurry, and mixing the cathode treatment mixed powder and water in a certain proportion to obtain cathode slurry.

[0054] It should be noted that, as disclosed in Chinese Patent No. CN116479448A, a recycling method for a recycling device of waste lithium iron phosphate battery positive electrode materials is used, the anode slurry is obtained by mixing the positive electrode material powder and the anode electrolyte. If the present disclosure adopts the traditional pulping method, since the conductivity difference between the internal and external electrolytes of the anode slurry is small, it is not conducive to the conduction of the valuable metal ions in the anode slurry to the external electrolyte to affect the ionization efficiency, and the cost of the electrolyte is higher than that of water, resulting in a problem of high processing cost. Therefore, in the present disclosure, the traditional electrolyte is directly replaced with water, so that the added water can not only serve as a solvent to achieve the wetting and dispersion of the anode treatment mixed powder, but also as a medium, which is conducive to the rapid conduction of the valuable metal ions in the anode slurry to the electrolyte in the electrolytic cell, so as to achieve comprehensive and efficient ionization of the anode slurry and the cathode slurry.

[0055] It is worth mentioning that in the present disclosure, the anode slurry and the cathode slurry are surrounded by an external electrolyte, so that the electrolyte and the anode slurry and the cathode slurry can form a good ion conduction system. For details, please refer to Figure 3 to ensure that during the ionization operation, the anode slurry and the cathode slurry can undergo comprehensive and efficient ionization.

[0056] It is also understood that when the mixing ratio of the anodic treatment mixed powder to water is high or low, or when the mixing ratio of the cathodic treatment mixed powder to water is high or low, the conduction efficiency of the valuable metal ions between the anode slurry, the electrolyte, and the cathode slurry will be affected. Therefore, in the present disclosure, by controlling the ratio of the anodic treatment mixed powder, the cathode treatment mixed powder, and water to be appropriate, a high conduction efficiency of the valuable metal ions between the anode slurry, the cathode slurry, and the electrolyte is ensured.

[0057] In a preferred embodiment, the mass ratio of the anode treatment mixed powder to water is 1:1, and the mass ratio of the cathode treatment mixed powder to water is 1:1, ensuring efficient conduction of valuable metal ions in the anode slurry, cathode slurry and electrolyte.

[0058] In one embodiment, before the step of obtaining n different types of waste positive battery powder, the method further includes the following step: crushing and screening each waste positive battery powder to obtain each waste positive battery powder with a particle size ≥5 μm.

[0059] It can be understood that the various types of recycled waste lithium batteries are disassembled to obtain different types of waste positive electrode sheets, which are then crushed and then sieved to obtain a variety of different types of waste positive electrode battery powders with a particle size of ≥5um.

[0060] It should be noted that if the particle size of waste positive battery powder is less than 5 μm, it is easy for the powder in the anode slurry and cathode slurry to escape from the anode basket and cathode basket or clog the mesh of the anode basket and cathode basket, resulting in a low ionization efficiency of the valuable metal ions in the cathode slurry or anode slurry, and it is impossible to ensure a high recovery rate of the valuable metal ions in the anode treatment mixed powder and cathode treatment mixed powder. Therefore, in the present disclosure, by controlling the particle size of multiple different types of waste positive battery powder to be ≥ 5 μm, the problem of powder escaping from the anode basket and cathode basket or clogging the mesh of the anode basket and cathode basket can be effectively avoided, and a high recovery rate of the valuable metal ions in the anode treatment mixed powder and cathode treatment mixed powder can be well ensured.

[0061] In one embodiment, when the anode slurry and the cathode slurry are ionized by the electrolysis device, the voltage is controlled to be 0.1V to 10V and the current density is 5A / cm 2 ~25A / cm 2The ionization time is 20 minutes to 240 minutes, ensuring that the valuable metal ions in the anode slurry and the cathode slurry can be ionized quickly and comprehensively, thereby achieving efficient and comprehensive ionization of the valuable metal ions in the anode slurry and the cathode slurry.

[0062] In one embodiment, before the step of ionizing the anode slurry and the cathode slurry through the electrolysis device and after the step of slurrying the anode treatment mixed powder and the cathode treatment mixed powder respectively, the following step is also included: adding electrolyte to the electrolysis device to ensure the normal operation of the electrolysis device.

[0063] In one embodiment, when adding electrolyte to the electrolysis device, the electrolyte is stirred by a stirrer in the electrolysis device. This not only ensures a uniform electrolyte, but also increases the fluidity of the electrolyte, thereby facilitating the rapid conduction of valuable metal ions between the anode slurry, electrolyte, and cathode slurry. In one embodiment, the stirring speed is 100 rpm to 350 rpm, ensuring good electrolyte fluidity and facilitating the rapid conduction of valuable metal ions.

[0064] It is understood that if the total added amount ratio of electrolyte to spent positive battery powder is too high or too low, efficient and comprehensive ionization of the anode slurry and cathode slurry cannot be ensured. Therefore, in one embodiment, the ratio of the added amount of electrolyte to the total added amount of n types of spent positive battery powder is (1-10) L:1 kg, ensuring that the ratio of electrolyte to n types of spent positive battery powder is appropriate and that efficient and comprehensive ionization rate of valuable metal ions in the anode slurry and cathode slurry is guaranteed.

[0065] In one embodiment, the concentration of the electrolyte is 10 g / L to 40 g / L.

[0066] In one embodiment, the electrolyte includes at least dilute sulfuric acid, and can also be independently selected from at least one of a sulfate system electrolyte, a chloride system electrolyte, and a nitrate system electrolyte.

[0067] It can be understood that in order to achieve good conduction of the electrolyte, in the present disclosure, dilute sulfuric acid is used as the electrolyte so that the dilute sulfuric acid can produce more H + , so that the generated H + Not only can it achieve the conduction of valuable metal ions, but it can also well meet the reaction of the cathode slurry to ensure comprehensive and efficient ionization of the cathode slurry. Of course, those skilled in the art can further select other types of electrolytes according to actual production needs, such as one selected from a sulfate system electrolyte, a chloride system electrolyte, and a nitrate system electrolyte and compounded with dilute sulfuric acid to achieve the same electrolyte conduction effect.

[0068] In a preferred embodiment, the sulfate system electrolyte is a sodium sulfate solution.

[0069] In a preferred embodiment, the chloride salt system electrolyte is a sodium chloride solution.

[0070] In one embodiment, the waste positive electrode battery powder includes at least one of lithium iron phosphate battery powder, lithium iron manganese phosphate battery powder, ternary battery powder, lithium cobalt oxide battery powder and lithium manganese oxide battery powder.

[0071] It should be noted that in actual applications, waste lithium batteries must undergo pre-processing before waste positive battery powder can be obtained. The specific operation is: the collected waste lithium batteries are sorted, and waste lithium batteries of the same type are disassembled and crushed as a group. Then, the same type of waste positive battery powder is obtained. Then, the valuable metal ions in the waste positive battery powder of a specific type are recovered. In this way, the valuable metal ions in the waste positive battery powder of the same type are recovered. However, when sorting waste lithium batteries, it is easy to make mistakes, resulting in the final crushed and screened battery powder being mixed with waste positive battery powder of multiple different types. This will make it difficult to effectively recycle the valuable metals in the mixed waste positive battery powder. To solve the above problem, some scholars have attempted to use separation technology to separate the two. However, due to the powder particles, simple screening cannot achieve a comprehensive separation and is relatively difficult. Some scholars have tried chemical methods to treat the waste. For example, Chinese patent number CN115109936B can achieve the coordinated leaching treatment of the positive electrode powder of waste lithium iron phosphate batteries and the positive electrode powder of waste ternary lithium batteries. However, because it adopts a chemical treatment method, the conditions are relatively harsh, the process is complicated, and the leaching rate of valuable metal ions is low.

[0072] Therefore, in one embodiment, before the step of filtering the anode slurry and cathode slurry after the ionization operation, and after the step of ionizing the anode slurry and cathode slurry through the electrolysis device, the following step is also included: replacing the anode and cathode plates of the electrolysis device, and then performing the ionization operation.

[0073] It can be understood that when the positive and negative plates of the electrolysis device are replaced and ionization is carried out, the original anode slurry will become cathode slurry, and the original cathode slurry will become anode slurry, realizing the reverse conduction of valuable metal ions, ensuring that the valuable metal ions in the anode slurry and cathode slurry can be fully ionized, thereby realizing efficient and comprehensive ionization of various types of waste positive battery powder.

[0074] It is worth mentioning that, due to the different redox properties of different types of waste positive battery powder, if the final crushed and screened battery powder is doped with waste positive battery powder of the same type, that is, the doped ones are all oxidizing or all reducing, the present disclosure can achieve comprehensive ionization through a single ionization. However, if the final crushed and screened battery powder is waste positive battery powder of two different properties, oxidizing and reducing, a single ionization cannot achieve comprehensive ionization. Therefore, in the present disclosure, the anode and cathode plates of the electrolysis device are first replaced, and then the ionization operation, that is, the secondary ionization, is performed. At this time, the original anode slurry will become a new cathode slurry, and the original cathode slurry will become a new anode slurry. The new cathode slurry is then filtered to obtain a valuable metal ion solution, so as to achieve rapid, efficient and comprehensive ionization of waste positive battery powder doped with two different properties, oxidizing and reducing. This method is not only simple to operate, but also does not require the addition of additional chemical reagents, is green and environmentally friendly, and has efficient and comprehensive ionization.

[0075] It can be understood that due to the action of gravity, the anodizing mixed powder and the anodizing mixed powder will sink and accumulate in the anode slurry and the cathode slurry, thereby affecting the ionization efficiency of the valuable metal ions. Therefore, in one embodiment, when the anode slurry and the cathode slurry are ionized by the electrolysis device, the anode slurry and the cathode slurry are continuously aerated at the same time to ensure that the air injected can provide a large amount of air flow for the anode slurry and the cathode slurry. In this way, on the one hand, a large amount of air flow can ensure that the powder can flow well in the anode slurry and the cathode slurry, not only can the powder be expanded into a uniform slurry, but also can ensure that the slurry has good fluidity, so that the electrolysis device can ionize the anode slurry and the cathode slurry more quickly and more comprehensively under the condition of power on. Valent metal ions can be effectively prevented from sinking easily in the anode slurry or cathode slurry, which affects the ionization of the valuable metal ions. On the other hand, more oxygen in the air enters the cathode slurry, ensuring that the cathode slurry and the anode slurry can quickly and comprehensively undergo redox reactions, thereby achieving efficient and comprehensive ionization of the cathode slurry and the anode slurry. On the other hand, a larger gas flow rate can also help accelerate the conduction of the valuable metal ions in the anode slurry, the electrolyte and the cathode slurry, thereby achieving efficient and comprehensive ionization of the valuable metal ions in the anode slurry and the cathode slurry.

[0076] In one embodiment, continuous aeration is first initiated to achieve continuous aeration of the anode and cathode slurries, and then the power supply is activated to perform the ionization operation. This ensures that the powders in the anode and cathode slurries are evenly dispersed before ionization, allowing the electrolysis device to more quickly and comprehensively ionize the valuable metal ions in the anode and cathode slurries.

[0077] It is understandable that if the aeration volume is less than 20m 3 / min, it is impossible to ensure the fluidity of the powder in the anode slurry and cathode slurry, which will affect the ionization of valuable metal ions; if the aeration volume is greater than 40m 3 / min, the anode slurry and cathode slurry are prone to splashing. Therefore, in one embodiment, the aeration volume of the continuous aeration operation is 20m 3 / min~40m 3 / min, under the premise of satisfying the high fluidity of the powder in the anode slurry and the cathode slurry, it also ensures that the anode slurry and the cathode slurry are not prone to splashing, is also beneficial to accelerate the redox reaction of the cathode slurry and the anode slurry, and helps to accelerate the conduction effect of the valuable metal ions in the anode slurry, electrolyte and cathode slurry, so as to achieve efficient and comprehensive ionization of the valuable metal ions in the anode slurry and the cathode slurry.

[0078] In order to realize the ionization operation of the anode slurry and the cathode slurry, as shown in FIG2 , in one embodiment, the electrolysis device 10 includes an electrolytic cell 100, a power supply 200, an anode assembly, a cathode assembly, an aeration assembly, a feed assembly and a discharge assembly; the feed assembly includes an electrolyte feed pipe 610, an anode slurry feed pipe 620 and a cathode feed pipe 630, and the discharge assembly includes an electrolyte discharge pipe 710, an anode slurry discharge pipe 720 and a cathode discharge pipe 730, and the electrolyte feed pipe 610 and the electrolyte discharge pipe 710 are respectively connected to the electrolytic cell 100; the anode assembly includes an anode basket 310 and an anode plate 320, and the anode basket 310 is arranged in the electrolytic cell 100. The anode slurry feed pipe 620 and the anode slurry discharge pipe 720 are respectively connected to the anode basket 310, and the anode basket 310 is used to hold the anode slurry. The anode plate 320 is disposed in the anode basket 310 and is electrically connected to the positive electrode of the power supply unit 200. The cathode assembly includes a cathode basket 410 and a cathode plate 420. The cathode basket 410 is disposed in the electrolytic cell 100. The cathode slurry feed pipe and the cathode slurry discharge pipe are respectively connected to the cathode basket 410. The cathode basket 410 is used to hold the cathode slurry. The cathode plate 420 is disposed in the cathode basket 410 and is electrically connected to the negative electrode of the power supply unit 200. The two aeration plates 540 of the aeration assembly are respectively disposed in the anode basket 310 and the cathode basket 410. The two aeration plates 540 are respectively used to continuously aerate the anode slurry and the cathode slurry.

[0079] During use, the electrolyte first enters the electrolytic cell 100 through the electrolyte feed pipe 610, the anode slurry enters the anode basket 310 through the anode slurry feed pipe 620, and the cathode slurry enters the cathode basket 410 through the cathode slurry feed pipe. Then, the fan 510 of the aeration assembly is started to continuously aerate the anode slurry and cathode slurry in the anode basket 310 and the cathode basket 410. Then, the power supply unit 200 of the electrolysis device 10 is turned on to form an electrical circuit with the power supply unit 200, the anode plate 320, the cathode slurry, the cathode plate 420, and the electrolyte, thereby achieving simultaneous ionization of the anode slurry and the cathode slurry. After ionization is completed, the anode slurry in the anode basket 310 is pumped out and filtered to obtain an anodic electrolysis liquid and an anodic electrolysis residue. The slurry in the cathode basket 410 is also pumped out and filtered to obtain a cathodic electrolysis liquid and a cathodic electrolysis residue. The resulting anodic electrolysis liquid and cathodic electrolysis liquid are the valuable metal ion solutions.

[0080] In one embodiment, the electrolysis device 10 further includes a stirrer 800, which is disposed between the anode basket 310 and the cathode basket 410. It is understood that the added stirrer 800 can, on the one hand, ensure that the electrolyte is evenly distributed within the electrolytic cell 100, effectively preventing the solutes in the electrolyte from easily precipitating over time and thus affecting the conduction effect of the valuable metal ions. On the other hand, the electrolyte can have good fluidity under stirring conditions, better meeting the rapid conduction of the valuable metal ions in the anode slurry and the cathode slurry. In particular, when used in conjunction with continuous aeration operation, efficient and comprehensive ionization of the anode slurry and the cathode slurry is achieved, which is not only simple to operate, but also has high purity and efficiency of the valuable metal ions, low cost, and is environmentally friendly.

[0081] In one embodiment, the stirrer 800 is a non-conductive stirrer 800 to avoid the introduction of new impurity metal elements and to ensure the purity of the valuable metal ions. For example, the non-conductive stirrer 800 can be a plastic stirrer 800.

[0082] In one embodiment, the anode basket 310 and the cathode basket 410 are both mesh plastic baskets. The mesh plastic baskets can ensure that the anode basket 310 and the cathode basket 410 have a certain porosity so that the valuable metal ions can quickly and unimpededly pass through the anode basket 310 and the cathode basket 410 to achieve rapid conduction of the valuable metal ions. The pore size of the mesh plastic basket does not exceed 5 μm. If the pore size of the mesh plastic basket exceeds 5 μm, the powder in the anode slurry and the cathode slurry will easily escape from the anode basket 310 and the cathode basket 410, causing The phenomenon of low ionization leaching rate of valuable metal ions is solved. Therefore, in the present disclosure, by controlling the pore size of the mesh plastic basket to not exceed 5 μm and using a variety of different types of waste positive battery powder with a particle size of ≥ 5 μm, the particle size of the waste positive battery powder is made suitable for the pores of the anode basket 310 and the cathode basket 410, thereby ensuring that all the anode slurry is always ionized in the anode basket 310 and all the cathode slurry is finally ionized in the cathode basket 410, thereby ensuring a high recovery rate of valuable metal ions in the anode slurry and the cathode slurry.

[0083] In one embodiment, the mesh plastic basket is made of at least one of PP, PE, PTFE, and nylon to prevent the anode basket 310 and the cathode basket 410 from being ionized, thereby effectively ensuring the purity of the ultimately recovered valuable metals. Furthermore, since PP, PE, PTFE, and nylon have a certain porosity, the conduction of valuable metal ions is facilitated.

[0084] In one embodiment, the cathode plate 420 includes at least one of a graphite plate, a lead plate, and a titanium plate.

[0085] In one embodiment, the anode plate 320 is at least one of a graphite plate, a platinum plate, an iridium plate, a ruthenium plate, and a multi-element alloy plate.

[0086] In one embodiment, the aeration assembly includes a fan 510, an anode connecting tube 520, a cathode connecting tube 530, and two aeration plates 540. The fan 510 is disposed outside the electrolytic cell 100. The air outlet pipe of the fan 510 is connected to the anode connecting tube 520 and the cathode connecting tube 530, respectively. The anode connecting tube 520 is connected to the aeration holes 541 of one aeration plate 540, and the cathode connecting tube 530 is connected to the aeration holes 541 of the other aeration plate 540. When the fan 510 is started, the airflow generated by the fan 510 can flow through the air outlet pipe into the anode connecting tube 520 and the cathode connecting tube 530, respectively, and then enter the aeration plates 540 in the anode basket 310 and the cathode basket 410, respectively, and finally exit through the aeration holes 541, thereby aerating the anode slurry and the cathode slurry.

[0087] In one embodiment, the aeration plate 540 is disposed adjacent to the bottom of the anode basket 310 and / or the cathode basket 410, and is located directly below the anode plate 320 and / or the cathode plate 420. This allows the gas from the aeration plate 540 to spray upward from the bottom of the anode basket 310 or the cathode basket 410, ensuring that the gas from the aeration plate 540 can effectively agitate the anode slurry in the anode basket 310 or the cathode slurry in the cathode basket 410 to quickly form a uniform slurry. Furthermore, the aeration plate 540 can provide a certain amount of airflow within the anode slurry and the cathode slurry, ensuring that the anode slurry and the cathode slurry have good fluidity, which is beneficial for the electrolysis device 10 to quickly and comprehensively ionize the valuable metal ions in the anode slurry and the cathode slurry. In addition, the aeration plate 540 is located directly below the anode plate 320 and the cathode plate 420, so that the gas coming out of the aeration plate 540 is at a shorter distance from the cathode plate 420 and the anode plate 320, ensuring that the oxygen coming out of the aeration plate 540 can quickly contact the cathode slurry or the anode slurry, thereby accelerating the redox reaction of the anode slurry and the cathode slurry, and achieving efficient and comprehensive ionization of the anode slurry and the cathode slurry.

[0088] In one embodiment, a first end of the anode connecting pipe 520 is connected to the air outlet pipe of the fan 510 , and a second end of the anode connecting pipe 520 extends to the bottom of the anode basket 310 and is connected to the aeration plate 540 , so that the aeration plate 540 is disposed adjacent to the bottom of the anode basket 310 .

[0089] Similarly, in one embodiment, a first end of the cathode connecting tube 530 is connected to the air outlet pipe of the fan 510, and a second end of the cathode connecting tube 530 extends to the bottom of the cathode basket 410 and is connected to the aeration plate 540, so that the aeration plate 540 is disposed adjacent to the bottom of the cathode basket 410.

[0090] In one embodiment, a bend 550 is formed at the second end of the anode connecting tube 520. The bend 550 communicates with the aeration plate 540. This additional bend 550 extends the horizontal length of the aeration plate 540 relative to the anode basket 310, ensuring that the gas ejected from the aeration plate 540 effectively agitates the anode slurry to form a uniform slurry. Similarly, a bend 550 of a similar structure is also provided on the cathode connecting tube 530, ensuring that the gas ejected from the aeration plate 540 effectively agitates the cathode slurry to form a uniform slurry.

[0091] In one embodiment, there are multiple aeration holes 541. The additional multiple aeration holes 541 can form multiple airflows inside the anode slurry and the cathode slurry, ensuring that the multiple airflows can quickly agitate the anode slurry and the cathode slurry to form a uniform slurry.

[0092] In one embodiment, the aeration holes 541 are distributed in an elliptical shape, ensuring that the air flow in the middle of the aeration plate 540 is greater than the air flow at the two ends, so that an air flow difference can be formed between the inside of the anode slurry or cathode slurry and the surrounding edges, thereby accelerating the fluidity inside the anode slurry or cathode slurry, and quickly agitating the cathode slurry and the anode slurry to form a uniform slurry.

[0093] In one embodiment, the aeration plate 540 is connected to the anode connection pipe 520 at an angle, so that the gas ejected from the aeration plate 540 can form multiple, differently layered airflows within the anode basket 310. In particular, combined with the use of multiple aeration holes 541, this ensures that the multiple, differently layered airflows can more quickly agitate the anode slurry into a uniform slurry. Similarly, in one embodiment, the aeration plate 540 is connected to the cathode connection pipe 530 with a similar structure, ensuring that the multiple, differently layered airflows can more quickly agitate the cathode slurry into a uniform slurry.

[0094] In one embodiment, the aeration holes 541 of the aeration plate 540 are arranged toward the bottom of the anode basket 310 and / or the cathode basket 410, so that the gas from the aeration plate 540 can be directly sprayed onto the bottom of the anode basket 310 or the cathode basket 410, thereby flushing the bottom of the anode basket 310 and effectively preventing the bottom of the anode basket 310 from being easily clogged. In this way, while ensuring that the aeration plate 540 flushes the bottom of the anode basket 310, it also ensures that the aeration plate 540 can quickly agitate the anode slurry or the cathode slurry to form a uniform slurry, and also ensures that the anode slurry and the cathode slurry have high fluidity.

[0095] It is understood that positioning the aeration holes 541 toward the bottom of the anode basket 310 and / or cathode basket 410 increases the distance the gas needs to travel to reach the cathode plate 420, preventing oxygen from exiting the aeration plate 540 from quickly entering the anode slurry or cathode slurry, thereby affecting efficient and comprehensive ionization of the anode and cathode slurries. Therefore, in one embodiment, a predetermined distance is provided between the aeration plate 540 and the bottom of the cathode basket 410 to ensure an appropriate distance between the aeration plate 540 and the bottom of the cathode basket 410. While ensuring that the aeration plate 540 can flush the bottom of the anode basket 310, the distance between the aeration plate 540 and the cathode plate 420 is minimized to ensure that oxygen from the aeration plate 540 can quickly enter the anode and cathode slurries and that the aeration plate 540 can quickly agitate the anode and cathode slurries to form a uniform slurry.

[0096] It is understood that if the preset distance is less than 1 cm, the distance between the aeration disc 540 and the cathode plate 420 is too small, causing the cathode basket 410 to be easily deformed or damaged. If the preset distance is greater than 30 cm, the rapid inflow of oxygen is affected. Therefore, in one embodiment, the preset distance is 1 cm to 30 cm, which provides a suitable distance between the aeration disc 540 and the cathode plate 420, achieving efficient and comprehensive ionization of the anode slurry and the cathode slurry.

[0097] In one embodiment, the aperture of the aeration hole 541 is 1 mm to 5 mm, so that the air flow out of the aeration hole 541 is stable and reliable. While satisfying the requirement of agitating the slurry well, it also avoids splashing of the slurry, effectively avoiding the phenomenon that the air flow is too small to agitate the slurry or the air flow is too large to cause splashing of the slurry.

[0098] In one embodiment, the blower 510 is a Roots blower 510 , so that the Roots blower 510 can provide good aeration gas, ensuring that the anode slurry and the cathode slurry can be aerated continuously and stably.

[0099] In one embodiment, the amount of the anode treatment mixed powder added accounts for 1 / 10 to 3 / 4 of the volume of the anode basket 310; the amount of the cathode treatment mixed powder added accounts for 1 / 10 to 3 / 4 of the volume of the cathode basket 410, so as to ensure that the anode slurry and cathode slurry prepared subsequently will not escape during the continuous aeration operation, effectively avoiding the escape of the anode slurry and cathode slurry and affecting the recovery rate of the organic metal ions in the anode slurry and cathode slurry.

[0100] In one embodiment, the anode basket 310 and the cathode basket 410 are both 20 cm to 50 cm higher than the height of the electrolytic cell 100, so that the anode slurry and the cathode slurry are not likely to escape during continuous aeration operation, thereby ensuring comprehensive ionization and recovery of valuable metal ions in the anode slurry and the cathode slurry.

[0101] Compared with the prior art, the present invention has at least the following advantages:

[0102] The method of electrolyzing valuable metal ions in waste lithium battery powder of the present invention first obtains n different types of waste positive battery powder, then classifies the n types of waste positive battery powder according to the redox properties of different valuable metals in the waste positive battery powder, classifies the waste positive battery powders with strong reducing properties into a group of mixed powders for anode treatment, and classifies the waste positive battery powders with strong oxidizing properties into a group of mixed powders for cathode treatment, then prepares the waste positive battery powders into anode slurry and cathode slurry, and performs an ionization operation on the anode slurry and cathode slurry through an electrolysis device, so that the valuable metal ions in the anode slurry can be electrolyzed and released in the anode slurry, and a small amount of water in the anode slurry can be ionized to produce H +, the electrolyte will ionize the hydrogen ions, and at the same time, under the action of the electric field, the anode slurry will ionize the valuable metal ions, H + The hydrogen ions generated by the electrolyte can migrate to the cathode slurry under the action of the electric field. The cathode treatment mixed powder in the cathode slurry can react with the hydrogen ions, reducing the high-valent valuable metal ions in the cathode slurry to easily soluble low-valent metal ions. This achieves the ionization of the valuable metal ions in the cathode slurry, allowing the valuable metal ions in the anode slurry and the valuable metal ions in the cathode slurry to be enriched in the cathode slurry. This allows for the simultaneous ionization of multiple different types of waste lithium battery powder in the anode and cathode slurries, thereby achieving efficient and comprehensive ionization of multiple different types of waste lithium battery powder. This method is not only simple to operate, but also does not require the addition of additional chemical reagents, effectively avoiding the introduction of new impurities, and effectively ensuring the purity of the valuable metal ions. It is also low-cost, environmentally friendly, and has efficient and comprehensive ionization. It is particularly suitable for applications where multiple different types of waste battery positive electrode powder are doped during the crushing process.

[0103] Some specific examples are listed below. It should be noted that the following examples do not exhaust all possible situations, and the materials used in the following examples can be obtained from commercial channels unless otherwise specified.

[0104] Example 1

[0105] (1) Prepare 50 L of 10 g / L dilute sulfuric acid solution and pump it into the electrolytic cell through the electrolyte feed pipe;

[0106] (2) 10 kg of waste lithium iron phosphate battery powder and water were slurried in a weight ratio of 1:1 and pumped into the anode basket through the anode feed pipe; water was pumped into the cathode basket through the cathode feed pipe;

[0107] (3) Turn on the Roots blower and continue to aerate the anode basket and cathode basket. The aeration volume is 10m 3 / h;

[0108] (4) Turn on the electrolysis device: control the voltage to 8V and the current density to 10A / cm 2 The electrolysis time was 120 minutes, and the stirring speed was 200 rpm. After the electrolysis was completed, the anode slurry in the anode basket was pumped out and filtered to obtain the anodic electrolyte and anodic electrolytic residue. The catholyte was the valuable metal ion solution. The anodic electrolytic residue was tested and the calculated lithium leaching rate was 98.1%. The anodic electrolytic residue was iron phosphate slag.

[0109] Example 2

[0110] (1) Prepare 60 L of 20 g / L dilute sulfuric acid solution and pump it into the electrolytic cell through the electrolyte feed pipe;

[0111] (2) 10 kg of waste lithium iron phosphate battery powder and water were slurried in a weight ratio of 1:1 and pumped into the anode basket through the anode feed pipe;

[0112] (3) 10 kg of waste ternary battery powder and water were slurried in a weight ratio of 1:1 and pumped into the cathode basket through the cathode feed pipe;

[0113] (4) Turn on the Roots blower and continue to aerate the anode basket and cathode basket. The aeration volume is 15m 3 / h;

[0114] (5) Turn on the electrolysis device: control the voltage to 5V and the current density to 8A / cm 2 The electrolysis time is 240min, the stirring speed is 300r / min, and after the electrolysis is completed, the anode slurry in the anode basket is pumped out and filtered to obtain the anode electrolysis liquid and the anode electrolysis slag; the cathode slurry in the cathode basket is pumped out and filtered to obtain the cathode electrolysis liquid and the cathode electrolysis slag. The cathode electrolyte is a valuable metal ion solution. The anode electrolysis slag and the cathode electrolysis slag are respectively detected, and the lithium leaching rate of the lithium iron phosphate battery powder is calculated to be 99.0%, and the anode electrolysis slag is iron phosphate slag; the lithium leaching rate of the ternary battery powder is 98.5%, the nickel leaching rate is 97.2%, the cobalt leaching rate is 98.7%, and the manganese leaching rate is 95.8%.

[0115] Example 3

[0116] (1) Prepare 50 L of 40 g / L dilute sulfuric acid solution and pump it into the electrolytic cell through the electrolyte feed pipe;

[0117] (2) 3 kg of waste lithium iron phosphate battery powder and 3 kg of waste lithium iron manganese phosphate battery powder were slurried with water in a weight ratio of 1:3, and pumped into the anode basket through the anode feed pipe;

[0118] (3) 4 kg of waste ternary battery powder and 2 kg of waste lithium cobalt oxide battery powder were slurried with water in a weight ratio of 1:2 and pumped into the cathode basket through the cathode feed pipe;

[0119] (4) Turn on the Roots blower and continue to aerate the anode basket and cathode basket. The aeration volume is 22m 3 / h;

[0120] (5) Turn on the electrolysis device: control the voltage to 8V and the current density to 20A / cm 2The electrolysis time was 240 minutes, and the stirring speed was 300 r / min. After the electrolysis was completed, the anode slurry in the anode basket was pumped out and filtered to obtain the anodic electrolysis liquid and anode electrolysis slag. The cathode slurry in the cathode basket was pumped out and filtered to obtain the cathode electrolysis liquid and cathode electrolysis slag. The cathode electrolyte is a valuable metal ion solution. The anode electrolysis slag and cathode electrolysis slag were tested separately, and the calculated lithium leaching rate of lithium iron phosphate battery powder and lithium manganese iron phosphate battery powder was 98.5%. The anode electrolysis slag was iron phosphate slag. The lithium leaching rate of ternary battery powder and lithium cobalt oxide was 97.6%, the nickel leaching rate was 97.2%, the cobalt leaching rate was 93.5%, and the manganese leaching rate was 96.3%.

[0121] Example 4

[0122] (1) Prepare 50 L of 40 g / L dilute sulfuric acid solution and pump it into the electrolytic cell through the electrolyte feed pipe;

[0123] (2) 3 kg of waste lithium iron phosphate battery powder and 3 kg of waste lithium cobalt oxide battery powder were slurried with water in a weight ratio of 1:3 and pumped into the anode basket through the anode feed pipe;

[0124] (3) 4 kg of waste ternary battery powder and 2 kg of waste lithium manganese iron phosphate battery powder were slurried with water in a weight ratio of 1:2 and pumped into the cathode basket through the cathode feed pipe;

[0125] (4) Turn on the Roots blower and continue to aerate the anode basket and cathode basket. The aeration volume is 22m 3 / h;

[0126] (5) Turn on the electrolysis device: control the voltage to 8V and the current density to 20A / cm 2 , electrolysis time is 10min; stirring speed is 300r / min,

[0127] (6) After the electrolysis is completed, the anode and cathode plates of the electrolysis device are replaced and the electrolysis time is continued for 140 minutes. The anode slurry in the anode basket is pumped out and filtered to obtain the anode electrolysis liquid and anode electrolysis slag; the cathode slurry in the cathode basket is pumped out and filtered to obtain the cathode electrolysis liquid and cathode electrolysis slag; the original anode electrolyte is the valuable metal ion solution, and the anode electrolysis slag and cathode electrolysis slag are detected respectively, and the lithium leaching rate of the lithium iron phosphate battery powder is calculated to be 97.6%, the lithium leaching rate of the lithium manganese iron phosphate battery powder is 98.1%, the lithium leaching rate of the ternary battery powder and lithium cobalt oxide is 96.2%, the nickel leaching rate is 97.9%, the cobalt leaching rate is 95.4%, and the manganese leaching rate is 96.6%.

[0128] From the comparison of Examples 2 to 4 with Example 1, it can be seen that when the method of electrolyzing valuable metal ions in waste lithium battery powder disclosed in the present invention is used to ionize a variety of different types of waste positive battery powder, it is not only simple to operate, but also does not require the addition of other chemical reagents, effectively avoids the introduction of new impurities, and well ensures the purity of the valuable metal ions. It is also low-cost, green and environmentally friendly, and the ionization is efficient and comprehensive. As can be seen from Example 4, it is still applicable to waste battery positive electrode powders doped with a variety of different properties.

[0129] The above-described embodiments merely represent several embodiments of the present invention. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the patent for this invention shall be determined by the appended claims.

Claims

1. A method for electrolyzing valuable metal ions in waste lithium battery powder, characterized in that, It includes the following steps: Obtain n types of waste cathode battery powders of different types, where n≥2 and n is a positive integer; Classify according to the oxidation-reduction properties of different valuable metals in the n types of waste cathode battery powders to obtain an anodic treatment mixed powder and a cathodic treatment mixed powder respectively; Perform pulping operations on the anodic treatment mixed powder and the cathodic treatment mixed powder respectively to obtain an anodic slurry and a cathodic slurry; Perform ionization operations on the anodic slurry and the cathodic slurry through an electrolysis device (10); Filter the cathodic slurry after the ionization operation to obtain a post-cathodic electrolysis solution; wherein, the post-cathodic electrolysis solution is a valuable metal ion solution.

2. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 1, characterized in that, In the step of performing pulping operations on the anodic treatment mixed powder and the cathodic treatment mixed powder respectively, the dosage ratio of the anodic treatment mixed powder to the cathodic treatment mixed powder is the ratio of the number of electrons gained and lost by the two.

3. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 2, characterized in that, In the step of performing pulping operations on the anodic treatment mixed powder and the cathodic treatment mixed powder respectively, it includes the following specific steps: Mix the anodic treatment mixed powder and water in a certain proportion to obtain the anodic slurry, and Mix the cathodic treatment mixed powder and water in a certain proportion to obtain the cathodic slurry.

4. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 3, characterized in that, The mass ratio of the anodic treatment mixed powder to water is 1:1, and the mass ratio of the cathodic treatment mixed powder to water is 1:

1.

5. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 1, characterized in that, Before the step of obtaining n types of waste cathode battery powders of different types, it further includes the following steps: Crush and screen each waste cathode battery powder to obtain each waste cathode battery powder with a particle size ≥5um.

6. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 1, characterized in that, When ionizing the anode paste and the cathode paste through the electrolysis device (10), the voltage is 0.1V to 10V, and the current density is 5A / cm 2 ~25A / cm 2 , and the ionization time is 20 min to 240 min.

7. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 1, characterized in that, Before the step of performing ionization operations on the anodic slurry and the cathodic slurry through the electrolysis device (10), and after the step of performing pulping operations on the anodic treatment mixed powder and the cathodic treatment mixed powder respectively, it further includes the following steps: Add an electrolyte to the electrolysis device (10).

8. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 7, characterized in that, When adding the electrolyte to the electrolysis device (10), stir the electrolyte through the stirrer (800) of the electrolysis device (10).

9. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 7, characterized in that The dosage ratio of the added electrolyte to the total added dosage of the n types of waste cathode battery powders is (1-10) L:1 kg.

10. The method for electrolyzing valuable metal ions in waste lithium battery powder according to any one of claims 7 to 9, characterized in that, The electrolyte at least includes dilute sulfuric acid, and may also be independently selected from at least one of a sulfate system electrolyte, a chloride system electrolyte, and a nitrate system electrolyte.

11. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 10, characterized in that, The sulfate system electrolyte is a sodium sulfate solution.

12. The method for extracting valuable metal ions from waste lithium battery powder according to claim 10, characterized in that, The chloride system electrolyte is a sodium chloride solution.

13. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 1, characterized in that, The waste cathode battery powder includes at least one of a lithium iron phosphate battery powder, a lithium iron manganese phosphate battery powder, a ternary battery powder, a lithium cobalt oxide battery powder, and a lithium manganese oxide battery powder.

14. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 1, characterized in that, Before the step of filtering the anodic slurry and the cathodic slurry after the ionization operation respectively, after the step of performing ionization operations on the anodic slurry and the cathodic slurry through the electrolysis device (10), it further includes the following steps: Swap the anode and cathode plates (320) of the electrolysis device (10), and then perform the ionization operation.

15. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 1, characterized in that, When the ionization operation is performed on the anode slurry and the cathode slurry through the electrolysis device (10), a continuous aeration operation is simultaneously performed on the anode slurry and the cathode slurry.

16. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 15, characterized in that, The aeration volume of the continuous aeration operation is 20 m 3 / min to 40 m 3 / min.

17. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 1, wherein The electrolysis device (10) includes an electrolytic cell (100), a power supply unit (200), an anode assembly, a cathode assembly, an aeration assembly, a feeding assembly, and a discharging assembly. The feeding assembly includes an electrolyte feeding pipe (610), an anode slurry feeding pipe (620), and a cathode feeding pipe (630), and the discharging assembly includes an electrolyte discharging pipe (710), an anode slurry discharging pipe (720), and a cathode discharging pipe (730). The electrolyte feeding pipe (610) and the electrolyte discharging pipe (710) are respectively communicated with the electrolytic cell (100). The anode assembly includes an anode basket (310) and an anode plate (320). The anode basket (310) is arranged inside the electrolytic cell (100). The anode slurry feeding pipe (620) and the anode slurry discharging pipe (720) are respectively communicated with the anode basket (310). The anode basket (310) is used for containing the anode slurry. The anode plate (320) is arranged inside the anode basket (310) and is electrically connected to the positive electrode of the power supply unit (200). The cathode assembly includes a cathode basket (410) and a cathode plate (420). The cathode basket (410) is arranged inside the electrolytic cell (100). The cathode slurry feeding pipe and the cathode slurry discharging pipe are respectively communicated with the cathode basket (410). The cathode basket (410) is used for containing the cathode slurry. The cathode plate (420) is arranged inside the cathode basket (410) and is electrically connected to the negative electrode of the power supply unit (200). Two aeration discs (540) of the aeration assembly are respectively arranged inside the anode basket (310) and the cathode basket (410), and the two aeration discs (540) are respectively used for performing a continuous aeration operation on the anode slurry and the cathode slurry.

18. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 17, wherein The electrolysis device (10) further includes a stirrer (800), and the stirrer (800) is arranged between the anode basket (310) and the cathode basket (410).

19. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 17, characterized in that, Both the anode basket (310) and the cathode basket (410) are mesh plastic baskets, and the aperture of the mesh plastic basket does not exceed 5 μm.

20. The method for recovering valuable metal ions from waste lithium battery powder according to claim 19, characterized in that, The material of the mesh plastic basket includes at least one of PP, PE, PTFE, and nylon.

21. The method for extracting valuable metal ions from waste lithium battery powder according to claim 17, characterized in that, The cathode plate (420) includes at least one of a graphite plate, a lead plate, and a titanium plate.

22. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 17, wherein The anode plate (320) is at least one of a graphite plate, a platinum plate, an iridium plate, a ruthenium plate, and a multi-alloy plate.

23. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 17, characterized in that, The aeration assembly includes a fan (510), an anode connecting pipe (520), a cathode connecting pipe (530), and two of the aeration discs (540). The fan (510) is arranged outside the electrolytic cell (100). The air outlet pipes of the fan (510) are respectively communicated with the anode connecting pipe (520) and the cathode connecting pipe (530). The anode connecting pipe (520) is communicated with the air holes (541) of one of the aeration discs (540), and the cathode connecting pipe (530) is communicated with the air holes (541) of the other aeration disc (540).

24. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 17, wherein, The aeration disc (540) is arranged adjacent to the bottom of the anode basket (310) and / or the cathode basket (410), and the aeration disc (540) is located directly below the anode plate (320) and / or the cathode plate (420).

25. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 23, wherein The first end of the anode connecting pipe (520) is communicated with the air outlet pipe of the fan (510). The second end of the anode connecting pipe (520) extends to the bottom of the anode basket (310) and is communicated with the aeration disc (540).

26. The method for extracting valuable metal ions from waste lithium battery powder according to claim 23, wherein The first end of the cathode connecting pipe (530) is communicated with the air outlet pipe of the fan (510). The second end of the cathode connecting pipe (530) extends to the bottom of the cathode basket (410) and is communicated with the aeration disc (540).

27. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 25 or 26, characterized in that, A bending portion (550) is formed at the second end of the anode connecting pipe (520) and / or the second end of the anode connecting pipe (520), and the bending portion (550) is communicated with the aeration disc (540).

28. The method for recovering valuable metal ions from waste lithium battery powder according to claim 23, wherein, The aperture of the air hole (541) is 1 mm to 5 mm.

29. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 23, characterized in that, The number of the air holes (541) is multiple, and the distribution of each of the air holes (541) is elliptical.

30. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 23, characterized in that, The aeration disc (540) is connected to the anode connecting pipe (520) and / or the cathode connecting pipe (530) at an inclined angle.

31. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 23, characterized in that, The fan (510) is a Roots blower (510).

32. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 17, characterized in that, The addition amount of the anode treatment mixed powder accounts for 1 / 10 to 3 / 4 of the volume of the anode basket (310); the addition amount of the cathode treatment mixed powder accounts for 1 / 10 to 3 / 4 of the volume of the cathode basket (410).

33. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 17, wherein Both the anode basket (310) and the cathode basket (410) are 20 cm to 50 cm higher than the height of the electrolytic cell (100).

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