Method for recovering valuable metal ions from waste lithium battery powder by electrolysis

Abstract

The present disclosure provides a method for electrolyzing valuable metal ions in waste lithium battery powder, which includes the following steps: obtaining n different types of waste positive electrode battery powder, where n≥2 and n is a positive integer; classifying the n types of waste positive electrode battery powder to respectively obtain an anodic treatment mixed powder and a cathodic treatment mixed powder; performing pulping operations on the anodic treatment mixed powder and the cathodic treatment mixed powder respectively to obtain an anodic slurry and a cathodic slurry; performing ionization operations on the anodic slurry and the cathodic slurry through an electrolysis device; filtering the cathodic slurry after the ionization operation to obtain a cathodic post-electrolysis solution, which is a valuable metal ion solution, realizing the efficient and comprehensive ionization recovery of valuable metal ions in two or more types of waste positive electrode powders, and the operation is simple and environmentally friendly.

Description

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 wide application of new energy vehicles, the number of waste lithium batteries generated is also increasing. The method for treating waste lithium batteries usually first screens out the batteries with a remaining capacity of 70%-80% of the initial capacity, and then uses them as carriers of electric energy for reuse to avoid waste; then disassembles and recycles the waste lithium batteries with a lower remaining capacity to effectively recover valuable metal ions such as nickel, cobalt, manganese, and lithium ions in the battery powder, thereby effectively alleviating the shortage of valuable metals such as nickel, cobalt, manganese, and lithium in the country.

[0003] At present, most of the recycling methods for waste lithium batteries adopt dry recycling or wet recycling. Wet recycling is the mainstream recycling method at present. It mainly uses chemical reagents to leach the battery powder, and then separates and removes impurities to effectively extract nickel, cobalt, manganese, and lithium ions in the battery powder. However, wet recycling has problems such as low leaching efficiency, long reaction cycle, and environmental unfriendliness. For this reason, a new recycling method - electrolysis method - has emerged on the market.

[0004] For example, Chinese Patent No. CN116479448A discloses a recycling device and a recycling method for the cathode material of waste lithium iron phosphate batteries. It mainly soaks and filters the disassembled lithium iron phosphate cathode material powder in an organic solvent to obtain the lithium-containing cathode material powder, and then pours the lithium-containing cathode material powder and the anolyte into the anode area of the electrolytic cell and conducts an electrolysis reaction through an oxygen supply pipe to achieve high-efficiency ionization of the waste lithium iron phosphate material. It not only has high ionization efficiency, short reaction time, but also is environmentally friendly. However, since the traditional electrolytic recycling method can only ionize and decompose a single type of waste cathode powder and cannot simultaneously achieve the ionization and decomposition of two or more types of waste cathode powders, there is a phenomenon of low ionization efficiency of waste cathode powder. Summary of the Invention

[0005] The object of the present invention is to overcome the deficiencies in the prior art and provide a method for electrolyzing valuable metal ions in waste lithium battery powder that is efficient and comprehensive in ionizing and recycling valuable metal ions in two or more types of waste cathode powders, and is simple to operate and environmentally friendly.

[0006] The object of the present invention is achieved by the following technical solutions:

[0007] A method for electrolyzing valuable metal ions in waste lithium battery powder includes the following steps:

[0008] Obtain n different types of waste cathode battery powders, where n≥2 and n is a positive integer;

[0009] Classify according to the oxidation-reduction properties of different valuable metals in the n kinds of waste cathode battery powders to obtain an anodic treatment mixed powder and a cathodic treatment mixed powder respectively;

[0010] 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;

[0011] Perform ionization operations on the anodic slurry and the cathodic slurry through an electrolysis device;

[0012] Filter the cathodic slurry after the ionization operation to obtain a post-electrolysis cathodic solution; wherein, the post-electrolysis cathodic solution is a valuable metal ion solution.

[0013] Details of one or more embodiments of the present invention are set forth in the following drawings and description. Other features, objects, and advantages of the present invention will become apparent from the specification, drawings, and claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] To more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required for use in the embodiments. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can also be obtained based on these drawings without creative efforts.

[0015] Figure 1 It is a flowchart of a method for electrolyzing valuable metal ions in waste lithium battery powder according to an embodiment of the present invention;

[0016] Figure 2 It is a schematic structural diagram of an electrolysis device in one direction according to an embodiment of the present invention;

[0017] Figure 3 It is an ion flow diagram during the ionization process of an anodic slurry and a cathodic slurry according to an embodiment of the present invention.

[0018] Reference numerals: 10, electrolysis device; 100, electrolytic cell; 200, power supply component; 310, anode basket; 320, anode plate; 410, cathode basket; 420, cathode plate; 510, fan; 520, anode connecting pipe; 530, cathode connecting pipe; 540, aeration disc; 541, aeration holes; 550, bending part; 610, electrolyte feed pipe; 620, anodic slurry feed pipe; 630, cathodic slurry feed pipe; 710, electrolyte discharge pipe; 720, anodic slurry discharge pipe; 730, cathodic slurry discharge pipe; 800, stirrer. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0019] To facilitate the understanding of the present invention, the present invention will be described more comprehensively below with reference to the relevant drawings. Preferred embodiments of the present invention are shown in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided to make the disclosure of the present invention more thorough and comprehensive.

[0020] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly on the other element or there can also be an intermediate element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be an intermediate element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only and do not represent the only embodiments.

[0021] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention belongs. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0022] Please refer to Figure 1 , 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 of the present disclosure, the following further explains and describes the method for electrolyzing valuable metal ions in waste lithium battery powder of the present disclosure:

[0023] The method for electrolyzing valuable metal ions in waste lithium battery powder in one embodiment includes the following steps:

[0024] S100. Obtain n different types of waste cathode battery powders, where n≥2 and n is a positive integer. It can be understood that by disassembling 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, waste lithium nickel cobalt aluminum oxide batteries, etc., n different types of waste cathode sheets are obtained, and then the n waste cathode sheets are crushed and screened to obtain n different types of waste cathode battery powders for standby.

[0025] S200. Classify according to the oxidation-reduction properties of different valuable metals in the n waste cathode battery powders to obtain an anodic treatment mixed powder and a cathodic treatment mixed powder respectively.

[0026] It can be understood that since the valuable metal components in different types of waste cathode battery powders are different, users can classify according to the oxidation-reduction properties of different valuable metals in n types of waste cathode battery powders, making multiple waste cathode battery powders with strong reducibility as a group for anodic treatment of the mixed powder; multiple waste cathode battery powders with strong oxidizing properties as a group for cathodic treatment of the mixed powder, ensuring that the subsequent preparation of anode slurry and cathode slurry can undergo ionization reactions simultaneously.

[0027] S300. Perform pulping operations on the anodic treatment mixed powder and the cathodic treatment mixed powder respectively to obtain anode slurry and cathode slurry.

[0028] It can be understood that since waste cathode battery powders are all powder particles, if they are directly poured into the electrolytic cell, it is easy to cause powder flying and loss, and the powder particles are not conducive to pumping. Therefore, in the present disclosure, by performing pulping operations on the anodic treatment mixed powder and the cathodic treatment mixed powder respectively to obtain anode slurry and cathode slurry, in this way, it is not only conducive to pumping into the anode basket and the cathode basket, but also ensures that the anodic treatment mixed powder and the cathodic treatment mixed powder can fully enter the electrolytic cell, improving the recovery rate of valuable metal ions in the anodic treatment mixed powder and the cathodic treatment mixed powder, and ensuring the normal operation of the ionization operation.

[0029] S400. Perform ionization operations on the anode slurry and the cathode slurry through an electrolysis device.

[0030] It can be understood that when ionizing the anode slurry and the cathode slurry, the valuable metal ions in the anode slurry can be electrolytically dissociated in the anode slurry to achieve the ionization of the valuable metal ions in the anode slurry. A small amount of water in the anode slurry can be ionized to produce H + , the electrolyte will ionize hydrogen ions. At the same time, under the action of the electric field, the valuable metal ions, H + produced by the ionization of the anode slurry and the hydrogen ions produced by the electrolyte can migrate to the cathode slurry under the action of the electric field. The cathodic treatment mixed powder in the cathode slurry can react with the hydrogen ions, so that the valuable metal ions in the high valence state in the cathode slurry can be reduced to metal ions in the easily soluble low valence state, realizing the ionization of the valuable metal ions in the cathode slurry, and enabling the valuable metal ions in the anode slurry and the valuable metal ions in the cathode slurry to be enriched in the cathode slurry, that is, simultaneously performing efficient and comprehensive ionization on the valuable metal ions in the anode slurry and the cathode slurry, and realizing the simultaneous ionization operation of two or more different types of waste lithium battery powders.

[0031] Please refer to Figure 3 , for the convenience of understanding the ionization principle of the anode slurry and the cathode slurry of the present disclosure, the specific ionization principle will be described below. Among them, the anodic treatment mixed powder is a mixed powder of LiFePO4 and LiFeMn(PO4)2, and the cathodic treatment mixed powder is LiNi XCoYMn 1-X-Y A mixed powder of O2, LiCoO2 and LiMn2O4, and the electrolyte is dilute sulfuric acid:

[0032] The reactions occurring in the anode paste are:

[0033] LiFePO4 - e - = Li + + FePO4;

[0034] LiFeMn(PO4)2 - 2e - = 2Li + + FePO4 + MnPO4;

[0035] 2H2O - 4e - = 4H + + O2;

[0036] The reactions of the electrolyte are:

[0037] H2SO4 = 2H + + SO4 - ;

[0038] It should be noted that when the anode paste is a mixed powder of LiFePO4 and LiFeMn(PO4)2 for anode treatment, since the reducibility of LiFePO4 is stronger than that of LiFeMn(PO4)2, LiFePO4 is ionized first, and then LiFeMn(PO4)2 is ionized. Also, part of the water in the anode paste will undergo electrolysis to produce H + , and the hydrogen ions ionized by the electrolyte under the action of the electric field. At the same time, under the action of the electric field, the Li + , H + ionized from the anode paste and the H + ionized from the electrolyte will migrate to the cathode paste. In this way, the H + produced by the electrolyte can achieve the conduction of valuable metal ions between the anode paste and the cathode paste.

[0039] The reactions occurring in the cathode paste are:

[0040] LiNi X Co Y Mn 1-X-Y O2 + 4H + + e - = Li + + XNi 2+ + YCo 2+ +(1 - X - Y)Mn 2+ + 2H2O;

[0041] LiCoO2 + 4H + + e- = Li + + Co 2+ + 2H2O;

[0042] LiMn2O4 + 8H + + e - = Li + + 2Mn 2+ + 4H2O;

[0043] O2 + 4H + + 2e - = 2H2O。

[0044] It should be noted that when the cathode-treated mixed powder is a mixed powder of LiNi X CoYMn 1-X-Y O2, LiCoO2 and LiMn2O4, when Li + , H + ionized from the anode slurry and H + ionized from the electrolyte migrate to the cathode slurry, because the oxidation order 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 reacts with H + first, enabling the high-valence Li, Ni, Co, and Mn to be reduced to low-valence valuable metal ions and dissociate in the cathode slurry. After LiNi X Co Y Mn 1-X-Y O2 has completely reacted, LiCoO2 will enter the reaction, and finally LiMn2O4, realizing the ionization recovery of the cathode slurry; at the same time, Li + migrated from the anode slurry will be enriched in the cathode slurry.

[0045] It should also be noted that when continuous aeration operation is performed on the cathode slurry, it can provide oxygen for the cathode slurry to ensure that the cathode-treated mixed powder can undergo redox reactions quickly and comprehensively, so as to ensure the efficient and comprehensive ionization of the cathode slurry.

[0046] S500, filter the cathode slurry after the ionization operation respectively to obtain the post-cathode electrolysis solution; among them, the post-cathode electrolysis solution is the valuable metal ion solution.

[0047] It can be understood that the cathode slurry after the ionization operation is filtered to separate the liquid and the slag in the cathode slurry, so that the valuable metal ions in the cathode slurry can be completely free in the cathode electrolysis solution, and the valuable metal ions ionized from the anode slurry will also be enriched in the cathode slurry, that is, the efficient ionization of the valuable metal ions in various types of waste lithium battery powders in the anode slurry and the cathode slurry is realized.

[0048] It should be noted that there are currently some electrolysis methods applied to valuable metals in waste lithium battery powders. For example, a method for recovering metals from waste lithium battery cathode materials disclosed in Chinese Patent No. CN112251776B, and a recovery device and a recovery method for waste lithium iron phosphate battery cathode materials disclosed in Chinese Patent No. CN116479448A. However, the above-mentioned electrolysis methods can only achieve the treatment of a single type and cannot achieve efficient treatment of two or more types. In order to find an efficient treatment and recovery method for valuable metals in waste lithium battery powders, some scholars have developed a method for recovering valuable metals in waste batteries such as Chinese Patent No. CN115109936B. Although it can achieve the co-leaching treatment of the cathode powder of waste lithium iron phosphate batteries and the cathode powder of waste ternary lithium batteries, due to the use of chemical treatment methods, there are problems such as relatively harsh conditions, complex processes, and low leaching rates of valuable metal ions.

[0049] In order to find an efficient treatment and recovery method for valuable metals in waste lithium battery powders, therefore, in this disclosure, first, n different types of waste cathode battery powders are obtained, and then they are classified according to the oxidation-reduction properties of different valuable metals in the n waste cathode battery powders. A group of waste cathode battery powders with strong reducibility are classified as the anode treatment mixed powder, and a group of waste cathode battery powders with strong oxidizability are classified as the cathode treatment mixed powder. Then, they are made into anode slurry and cathode slurry, and the anode slurry and the cathode slurry are subjected to ionization operations through an electrolysis device, so that the valuable metal ions in the anode slurry can be electrolyzed and free in the anode slurry, and a small amount of water in the anode slurry can be ionized to produce H + , the electrolyte will ionize hydrogen ions, and at the same time, under the action of the electric field, the valuable metal ions and H generated by the ionization of the anode slurry +The hydrogen ions generated by the electrolyte can migrate to the cathode slurry under the action of an electric field. The cathode treatment mixed powder in the cathode slurry can react with the hydrogen ions, reducing the high-valence valuable metal ions in the cathode slurry to low-valence metal ions that are easily soluble, realizing the ionization of the valuable metal ions in the cathode slurry. This enables the valuable metal ions in the anode slurry and the cathode slurry to be enriched in the cathode slurry, achieving the simultaneous ionization operation of various types of waste lithium battery powders in the anode slurry and the cathode slurry. This method is not only simple to operate, has high ionization efficiency, but also does not require the additional addition of other chemical reagents, effectively ensuring the purity of the valuable metal ions, having low cost, and being environmentally friendly. It is particularly suitable for applications where various types of waste battery cathode powders are doped during the crushing process.

[0050] In one embodiment, in the step of separately pulping the anode treatment mixed powder and the cathode treatment mixed powder, the dosage ratio of the anode treatment mixed powder to the cathode treatment mixed powder is the ratio of the number of electrons gained and lost by the two.

[0051] To ensure the electron balance throughout the ionization process, in this disclosure, the ratio is determined according to the number of electrons gained and lost in the anode treatment mixed powder and the cathode treatment mixed powder, ensuring that the valuable metal ions in the anode slurry and the cathode slurry can undergo comprehensive ionization and improving the ionization efficiency of the valuable metals in the anode slurry and the cathode slurry.

[0052] In one embodiment, in the step of separately pulping the anode treatment mixed powder and the cathode treatment mixed powder, the following specific steps are included: mixing the anode treatment mixed powder and water in a certain proportion to obtain the anode slurry, and mixing the cathode treatment mixed powder and water in a certain proportion to obtain the cathode slurry.

[0053] It should be noted that as disclosed in Chinese Patent No. CN116479448A for the recovery method of a waste lithium iron phosphate battery cathode material recovery device, the anode slurry is obtained by mixing the cathode material powder and the anode electrolyte. If the traditional pulping method is used in this disclosure, due to the small conduction difference between the inside and outside of the anode slurry and the external electrolyte, it is not conducive to the conduction of valuable metal ions in the anode slurry to the external electrolyte, affecting the ionization efficiency, and the cost of the electrolyte is higher than that of water, resulting in a higher treatment cost. Therefore, in this disclosure, the traditional electrolyte is directly replaced with water, so that the added water can not only act as a solvent to wet and disperse the anode treatment mixed powder, but also act as a medium, facilitating the rapid conduction of valuable metal ions in the anode slurry to the electrolyte in the electrolytic cell, to achieve comprehensive and efficient ionization of the anode slurry and the cathode slurry.

[0054] It is worth mentioning that in this disclosure, the anode slurry and the cathode slurry are surrounded by the external electrolyte, enabling the electrolyte to form a good ion conduction system with the anode slurry and the cathode slurry. For details, please refer toFigure 3 , ensure that under the ionization operation, the anode slurry and the cathode slurry can undergo comprehensive and efficient ionization.

[0055] It can also be understood that when the mixing ratio of the anode-treated mixed powder and water is too high or too low; or when the mixing ratio of the cathode-treated mixed powder and water is too high or too low, it will affect the conduction effect of valuable metal ions in the anode slurry, electrolyte, and cathode slurry. Therefore, in the present disclosure, by controlling the anode-treated mixed powder, cathode-treated mixed powder, and water in appropriate proportions, it is ensured that valuable metal ions have a high conduction efficiency between the anode slurry, cathode slurry, and electrolyte.

[0056] In a preferred embodiment, the mass ratio of the anode-treated mixed powder to water is 1:1, and the mass ratio of the cathode-treated mixed powder to water is 1:1, ensuring the efficient conduction of valuable metal ions in the anode slurry, cathode slurry, and electrolyte.

[0057] In one of the embodiments, before the step of obtaining n different types of waste cathode battery powders, the following steps are further included: crushing and screening each waste cathode battery powder to obtain each waste cathode battery powder with a particle size ≥ 5um.

[0058] It can be understood that various recovered waste lithium batteries are disassembled to obtain different types of waste cathode sheets, then the different types of waste cathode sheets are crushed, and then sieved to obtain various different types of waste cathode battery powders with a particle size ≥ 5um.

[0059] It should be noted that if the particle size of the waste cathode battery powder is less than 5um, it is easy for the powder in the anode slurry and cathode slurry to escape from the anode basket and cathode basket or block the mesh holes of the anode basket and cathode basket, resulting in a low ionization efficiency of valuable metal ions in the cathode slurry or anode slurry, and unable to ensure a high recovery rate of valuable metal ions in the anode-treated mixed powder and cathode-treated mixed powder. Therefore, in the present disclosure, by controlling the particle size of various different types of waste cathode battery powders ≥ 5um, the problem that the powder escapes from the anode basket and cathode basket or blocks the mesh holes of the anode basket and cathode basket can be effectively avoided, and a high recovery rate of valuable metal ions in the anode-treated mixed powder and cathode-treated mixed powder can be well ensured.

[0060] In one of the embodiments, when performing the ionization operation on the anode slurry and the cathode slurry through the electrolysis device, by controlling the voltage to be 0.1V to 10V and the current density to be 5A / cm 2 ~25A / cm 2 , and the ionization time is 20min to 240min, it is ensured that valuable metal ions in the anode slurry and cathode slurry can be ionized quickly and comprehensively, realizing the efficient and comprehensive ionization of valuable metal ions in the anode slurry and cathode slurry.

[0061] In one embodiment, before the step of ionizing the anode slurry and the cathode slurry by the electrolysis device and after the step of pulping the anode-treated mixed powder and the cathode-treated mixed powder respectively, the following steps are further included: adding an electrolyte solution to the electrolysis device to ensure the normal operation of the electrolysis device.

[0062] In one embodiment, when adding the electrolyte solution to the electrolysis device, the electrolyte solution is stirred by a stirrer of the electrolysis device. On the premise of ensuring a uniform electrolyte solution, the fluidity of the electrolyte solution is also increased, which is beneficial to the rapid conduction of valuable metal ions in the anode slurry, the electrolyte solution and the cathode slurry. In one embodiment, the rotation speed of the stirring operation is 100 r / min to 350 r / min, ensuring better fluidity of the electrolyte solution and being more conducive to the rapid conduction of valuable metal ions.

[0063] It can be understood that if the total addition ratio of the electrolyte solution to the waste positive electrode battery powder is too high or too low, the efficient and comprehensive ionization of the anode slurry and the cathode slurry cannot be ensured. Therefore, in one embodiment, the addition ratio of the electrolyte solution to the total addition amount of n types of waste positive electrode battery powder is (1 to 10) L: 1 kg, ensuring an appropriate ratio of the electrolyte solution to n types of waste positive electrode battery powder and guaranteeing a high and comprehensive ionization rate of valuable metal ions in the anode slurry and the cathode slurry.

[0064] In one embodiment, the concentration of the electrolyte solution is 10 g / L to 40 g / L.

[0065] In one embodiment, the electrolyte solution at least includes dilute sulfuric acid and can also be independently selected from at least one of a sulfate system electrolyte solution, a chloride system electrolyte solution and a nitrate system electrolyte solution.

[0066] It can be understood that in order to achieve good conduction of the electrolyte solution, in the present disclosure, dilute sulfuric acid is used as the electrolyte so that dilute sulfuric acid can generate more H + , so that the generated H + can not only achieve the conduction of valuable metal ions, but also well satisfy the reaction of the cathode slurry to ensure the comprehensive and efficient ionization of the cathode slurry. Of course, those skilled in the art can further select other types of electrolyte solutions according to actual production needs. For example, one selected from a sulfate system electrolyte solution, a chloride system electrolyte solution and a nitrate system electrolyte solution can be compounded with dilute sulfuric acid for use, and the conduction effect of the electrolyte solution can also be achieved.

[0067] In a preferred embodiment, the sulfate system electrolyte solution is a sodium sulfate solution.

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

[0069] In one embodiment, the waste cathode 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.

[0070] It should be noted that in actual applications, waste lithium batteries need to be pretreated to obtain waste cathode battery powder. The specific operation is as follows: Classify the collected waste lithium batteries so that the same type of waste lithium batteries are grouped together for centralized disassembly and crushing treatment, and then the same type of waste cathode battery powder is obtained. Then, recover the valuable metal ions in the special waste cathode battery powder. In this way, the recovery of valuable metal ions in the same type of waste cathode battery powder is completed. However, when classifying waste lithium batteries, it is easy to misclassify, resulting in the doped waste cathode battery powder containing multiple different types of waste cathode battery powder after final crushing and screening. In this way, the valuable metals in the doped waste cathode battery powder cannot be well recycled. To solve the above problems, some scholars have tried to use separation technology to achieve the separation of the two, but because they are powder particles, simple sieving cannot achieve a comprehensive separation of them, and the difficulty is relatively high. Some other scholars have tried chemical methods to treat, such as Chinese Patent No. CN115109936B. Although it can achieve the co-leaching treatment of the cathode powder of waste lithium iron phosphate batteries and the cathode powder of waste ternary lithium batteries, due to the chemical treatment method adopted, there are problems such as relatively harsh conditions, complex processes, and relatively low leaching rates of valuable metal ions.

[0071] Therefore, in one embodiment, before the steps of separately filtering the anode slurry and the cathode slurry after the ionization operation, after the step of ionizing the anode slurry and the cathode slurry through an electrolysis device, the following steps are further included: Swap the anode and cathode plates of the electrolysis device, and then perform the ionization operation.

[0072] It can be understood that when ionizing after swapping the anode and cathode plates of the electrolysis device, the original anode slurry will become the cathode slurry, and the original cathode slurry will become the anode slurry, realizing the reverse conduction of valuable metal ions, ensuring that the valuable metal ions in the anode slurry and the cathode slurry can be comprehensively ionized, thereby achieving efficient and comprehensive ionization of multiple different types of waste cathode battery powder.

[0073] It is worth mentioning that due to the different oxidation-reduction properties of different types of waste cathode battery powder, if the battery powder obtained after final crushing and screening is doped with waste cathode battery powder of the same property type, that is, all doped with oxidizing or reducing properties, the present disclosure can achieve comprehensive ionization of it through a single ionization. However, if the battery powder obtained after final crushing and screening contains waste cathode battery powder with two different properties of oxidation and reduction, a single ionization cannot achieve comprehensive ionization. Therefore, in the present disclosure, first, the anode and cathode plates of the electrolysis device are swapped, and then the ionization operation is carried out, that is, secondary ionization. At this time, the original anode slurry will become the new cathode slurry, and the original cathode slurry will become the new anode slurry. Then, the new cathode slurry is filtered to obtain a valuable metal ion solution, so as to achieve rapid, efficient, and comprehensive ionization of waste cathode battery powder doped with two different properties of oxidation and reduction. It is not only simple to operate, but also does not require additional chemical reagents, is green and environmentally friendly, and has high and comprehensive ionization efficiency.

[0074] It can be understood that due to the phenomenon of sinking and accumulation of the anode-treated mixed powder and the anode-treated mixed powder under the action of gravity in the anode slurry and the cathode slurry, the ionization efficiency of valuable metal ions will be affected. Therefore, in one embodiment, when the ionization operation is carried out on the anode slurry and the cathode slurry through the electrolysis device, a continuous aeration operation is simultaneously carried out on the anode slurry and the cathode slurry to ensure that the air filled can provide a large air flow rate for the anode slurry and the cathode slurry. In this way, on the one hand, a large air flow rate can ensure that the powder can flow well in the anode slurry and the cathode slurry, not only can the powder be blown into a uniform slurry, but also ensure that the slurry has good fluidity, so that the electrolysis device can more quickly and comprehensively ionize the valuable metal ions in the anode slurry and the cathode slurry under the condition of power-on, effectively avoiding the phenomenon that the powder in the anode slurry or the cathode slurry is prone to sink and affect the ionization of 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 oxidation-reduction reactions, achieving efficient and comprehensive ionization of the cathode slurry and the anode slurry. On the other hand, a large air flow rate also helps to accelerate the conduction effect of valuable metal ions in the anode slurry, electrolyte, and cathode slurry, so as to achieve efficient and comprehensive ionization of valuable metal ions in the anode slurry and the cathode slurry.

[0075] In one embodiment, first, the continuous aeration operation is started to achieve continuous aeration of the anode slurry and the cathode slurry, and then the power supply is started for the ionization operation. In this way, it is ensured that the powder in the anode slurry and the cathode slurry can be evenly dispersed before ionization, so that the electrolysis device can more quickly and comprehensively ionize the valuable metal ions in the anode slurry and the cathode slurry.

[0076] It can be understood that if the aeration volume is less than 20m 3 / min, it is unable to ensure the fluidity of the powders in the anode slurry and the cathode slurry well, which affects the ionization of valuable metal ions; if the aeration rate is greater than 40 m 3 / min, splashing of the anode slurry and the cathode slurry is likely to occur. Therefore, in one of the embodiments, the aeration rate for continuous aeration operation is 20 m 3 / min to 40 m 3 / min. On the premise of ensuring high fluidity of the powders in the anode slurry and the cathode slurry, it also ensures that the anode slurry and the cathode slurry are not prone to splashing, which is also conducive to accelerating the redox reaction of the cathode slurry and the anode slurry, and also helps to accelerate the conduction effect of valuable metal ions in the anode slurry, the electrolyte, and the cathode slurry, so as to achieve efficient and comprehensive ionization of valuable metal ions in the anode slurry and the cathode slurry.

[0077] To implement the ionization operation of the anode slurry and the cathode slurry, as Figure 2 shown, in one of the embodiments, 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 slurry feeding pipe 630, and the discharging assembly includes an electrolyte discharging pipe 710, an anode slurry discharging pipe 720, and a cathode slurry discharging pipe 730. The electrolyte feeding pipe 610 and the electrolyte discharging pipe 710 are respectively connected to the electrolytic cell 100; the anode assembly includes an anode basket 310 and an anode plate 320. The anode basket 310 is arranged in the electrolytic cell 100. The anode slurry feeding pipe 620 and the anode slurry discharging pipe 720 are respectively connected to the anode basket 310. The anode basket 310 is used to hold the anode slurry. The anode plate 320 is arranged 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 arranged in the electrolytic cell 100. The cathode slurry feeding pipe 630 and the cathode slurry discharging pipe 730 are respectively connected to the cathode basket 410. The cathode basket 410 is used to hold the cathode slurry. The cathode plate 420 is arranged in the cathode basket 410 and is electrically connected to the negative electrode of the power supply unit 200; the two aeration disks 540 of the aeration assembly are respectively arranged in the anode basket 310 and the cathode basket 410, and the two aeration disks 540 are respectively used to perform continuous aeration operation on the anode slurry and the cathode slurry.

[0078] When in use, first, the electrolyte enters the electrolytic cell 100 through the electrolyte feed pipe 610, and the anode slurry enters the anode basket 310 through the anode slurry feed pipe 620; the cathode slurry enters the cathode basket 410 through the cathode slurry feed pipe 630; then the fan 510 of the aeration assembly is started to achieve continuous aeration operation of the anode slurry and the cathode slurry in the anode basket 310 and the cathode basket 410, and then the power supply unit 200 of the electrolysis device 10 is turned on, so that the power supply unit 200, the anode plate 320, the cathode slurry, the cathode plate 420 and the electrolyte can form an electrical circuit to achieve simultaneous ionization operation of the anode slurry and the cathode slurry; after the ionization is completed, the anode slurry in the anode basket 310 is pumped out and filtered to obtain the anode electrolysis liquid and the anode electrolysis slag, and the slurry in the cathode basket 410 is pumped out and filtered to obtain the cathode electrolysis liquid and the cathode electrolysis slag, and the final obtained anode electrolysis liquid and cathode electrolysis liquid are the valuable metal ion solution.

[0079] 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 additional stirrer 800 can ensure that the electrolyte can be evenly distributed in the electrolytic cell 100, effectively preventing the electrolyte solute from being easily precipitated when used for a long time to affect the conduction effect of the valuable metal ions, and on the other hand, the electrolyte can have good fluidity under stirring conditions, better meet the rapid conduction of the valuable metal ions in the anode slurry and the cathode slurry, especially with the use of continuous aeration operation, to achieve efficient and comprehensive ionization operation of the anode slurry and the cathode slurry, which is not only simple to operate, but also has high purity of valuable metal ions, high ionization efficiency of valuable metal ions, low cost and green environmental protection.

[0080] In one embodiment, the agitator 800 is a non-conductive agitator 800 to avoid introducing new impurity metal elements and to ensure the purity of the valuable metal ions. For example, the non-conductive agitator 800 may be a plastic agitator 800.

[0081] In one embodiment, both the anode basket 310 and the cathode basket 410 are 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 valuable metal ions can quickly and unobstructedly pass through the anode basket 310 and the cathode basket 410 to achieve rapid conduction of valuable metal ions. The pore diameter of the mesh plastic basket does not exceed 5 μm. When the pore diameter of the mesh plastic basket exceeds 5 μm, the powder in the anode slurry and the cathode slurry is likely to escape from the anode basket 310 and the cathode basket 410, resulting in a low ionization leaching rate of valuable metal ions. Therefore, in the present disclosure, by controlling the pore diameter of the mesh plastic basket not to exceed 5 μm and at the same time cooperating with the use of various types of waste cathode battery powders with a particle size ≥ 5 μm, the particle size of the waste cathode battery powder is more suitable for the pores of the anode basket 310 and the cathode basket 410, 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, and ensuring a high recovery rate of valuable metal ions in the anode slurry and the cathode slurry.

[0082] In one embodiment, the material of the mesh plastic basket includes at least one of PP, PE, PTFE, and nylon, to ensure that the anode basket 310 and the cathode basket 410 will not be ionized, effectively ensuring the purity of the finally recovered valuable metals. At the same time, since PP, PE, PTFE, and nylon have a certain porosity, it is convenient for the conduction of valuable metal ions.

[0083] In one embodiment, the cathode plate 420 includes at least one of a graphite plate, a lead plate, and a titanium plate.

[0084] 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-alloy plate.

[0085] In one embodiment, the aeration assembly includes a blower 510, an anode connecting pipe 520, a cathode connecting pipe 530, and two aeration disks 540. The blower 510 is disposed outside the electrolytic cell 100. The air outlet pipes of the blower 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 aeration disk 540, and the cathode connecting pipe 530 is communicated with the air holes 541 of the other aeration disk 540. When the blower 510 is started, the airflow generated by the blower 510 can flow into the anode connecting pipe 520 and the cathode connecting pipe 530 respectively through the air outlet pipes, and then enter the aeration disks 540 in the anode basket 310 and the aeration disks 540 in the cathode basket 410 respectively, and finally come out from the air holes 541, realizing the aeration operation of the anode slurry and the cathode slurry.

[0086] In one embodiment, the aeration disk 540 is disposed adjacent to the bottom of the anode basket 310 and / or the cathode basket 410, and the aeration disk 540 is located directly below the anode plate 320 and / or the cathode plate 420, so that the gas coming out of the aeration disk 540 can spray upward from the bottom of the anode basket 310 or the cathode basket 410, ensuring that the gas coming out of the aeration disk 540 can well agitate the anode slurry in the anode basket 310 or the cathode slurry in the cathode basket 410 to quickly form a uniform slurry. At the same time, it can also provide a certain airflow inside the anode slurry and the cathode slurry, ensuring that the anode slurry and the cathode slurry have good fluidity, which is beneficial to 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 disk 540 is located directly below the anode plate 320 and the cathode plate 420, so that the distance between the gas coming out of the aeration disk 540 and the cathode plate 420 and the anode plate 320 is short, ensuring that the oxygen coming out of the aeration disk 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 realizing the efficient and comprehensive ionization of the anode slurry and the cathode slurry.

[0087] In one embodiment, the first end of the anode connecting pipe 520 is communicated with the air outlet pipe of the blower 510, and the second end of the anode connecting pipe 520 extends to the bottom of the anode basket 310 and is communicated with the aeration disk 540 to realize the arrangement of the aeration disk 540 adjacent to the bottom of the anode basket 310.

[0088] Similarly, in one embodiment, the first end of the cathode connecting pipe 530 is communicated with the air outlet pipe of the blower 510, and the second end of the cathode connecting pipe 530 extends to the bottom of the cathode basket 410 and is communicated with the aeration disk 540 to realize the arrangement of the aeration disk 540 adjacent to the bottom of the cathode basket 410.

[0089] In one embodiment, a bending portion 550 is formed at the second end of the anode connecting pipe 520, and the bending portion 550 is communicated with the aeration disk 540, so that the added bending portion 550 can extend the horizontal length of the aeration disk 540 in the anode basket 310, ensuring that the gas sprayed out by the aeration disk 540 can well agitate the anode slurry to form a uniform slurry. Similarly, the cathode connecting pipe 530 is also provided with a bending portion 550 with a similar structure to ensure that the gas sprayed out by the aeration disk 540 can well agitate the cathode slurry to form a uniform slurry.

[0090] In one embodiment, the number of the aeration holes 541 is multiple, and the added 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.

[0091] In one embodiment, the distribution of each aeration hole 541 is elliptical, ensuring that the air flow rate in the middle of the aeration disk 540 is greater than that at both ends, so as to form an air flow difference between the inside and the four peripheral edges of the anode paste or the cathode paste, accelerating the fluidity inside the anode paste or the cathode paste, and quickly agitating the cathode paste and the anode paste to form a uniform paste.

[0092] In one embodiment, the aeration disk 540 is connected to the anode connecting pipe 520 at an inclined angle, so that the gas ejected from the aeration disk 540 can form multiple air flows with different levels of layering in the anode basket 310. Especially in cooperation with the use of multiple aeration holes 541, it is ensured that the multiple air flows with different levels of layering can more quickly agitate the anode paste to form a uniform paste. Similarly, in one embodiment, the connection between the aeration disk 540 and the cathode connecting pipe 530 also has a similar structure, ensuring that the multiple air flows with different levels of layering can more quickly agitate the cathode paste to form a uniform paste.

[0093] In one embodiment, the aeration holes 541 of the aeration disk 540 are arranged towards the bottom of the anode basket 310 and / or the cathode basket 410, so that the gas coming out of the aeration disk 540 can be directly ejected onto the bottom of the anode basket 310 or the cathode basket 410, realizing the flushing of the bottom of the anode basket 310 and effectively avoiding the phenomenon of easy blockage at the bottom of the anode basket 310. In this way, on the premise of ensuring that the aeration disk 540 flushes the bottom of the anode basket 310, it is also ensured that the aeration disk 540 can quickly agitate the anode paste or the cathode paste to form a uniform paste, and it is also ensured that the anode paste and the cathode paste have high fluidity.

[0094] It can be understood that if the aeration holes 541 are arranged towards the bottom of the anode basket 310 and / or the cathode basket 410, the distance for the gas to reach the cathode plate 420 will be extended, resulting in the oxygen coming out of the aeration disk 540 being unable to quickly enter the anode paste or the cathode paste, thus affecting the efficient and comprehensive ionization of the anode paste and the cathode paste. Therefore, in one embodiment, a preset distance is provided between the aeration disk 540 and the bottom of the cathode basket 410 to ensure that the distance between the aeration disk 540 and the bottom of the cathode basket 410 is appropriate. On the premise of satisfying that the aeration disk 540 can flush the bottom of the anode basket 310, the distance between the aeration disk 540 and the cathode plate 420 is also minimized to ensure that the oxygen coming out of the aeration disk 540 can quickly enter the anode paste or the cathode paste, and it is also ensured that the aeration disk 540 can quickly agitate the anode paste or the cathode paste to form a uniform paste.

[0095] It can be understood that if the preset distance is less than 1 cm, the distance between the aeration disk 540 and the cathode plate 420 is too small, resulting in the cathode basket 410 being prone to deformation or damage. If the preset distance is greater than 30 cm, it will affect the rapid entry of oxygen. Therefore, in one embodiment, the preset distance is 1 cm to 30 cm, making the distance between the aeration disk 540 and the cathode plate 420 more appropriate, and achieving efficient and comprehensive ionization of the anode slurry and the cathode slurry.

[0096] In one embodiment, the aperture of the air holes 541 is 1 mm to 5 mm, making the air flow rate coming out of the air holes 541 stable and reliable. On the premise of satisfying the good agitation of the slurry, it also avoids the slurry from splashing, effectively avoiding the phenomenon that the air flow rate is too small to agitate the slurry or the air flow rate is too large to cause the slurry to splash.

[0097] 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 continuously and stably aerated.

[0098] In one embodiment, 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, so as to ensure that the anode slurry and the cathode slurry obtained subsequently will not escape during continuous aeration operation, effectively avoiding the escape of the anode slurry and the cathode slurry and affecting the recovery rate of the organic metal ions in the anode slurry and the cathode slurry.

[0099] In one embodiment, 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, making it not easy for the anode slurry and the cathode slurry to escape during continuous aeration operation, and ensuring the comprehensive ionization and recovery of the valuable metal ions in the anode slurry and the cathode slurry.

[0100] Compared with the prior art, the present invention has at least the following advantages:

[0101] The method for valuable metal ions in the electrolyzed waste lithium battery powder of the present invention first obtains n different types of waste positive electrode battery powders, and then classifies them according to the oxidation-reduction properties of different valuable metals in the n waste positive electrode battery powders. A group of waste positive electrode battery powders with strong reducibility are classified as the anode treatment mixed powder, and a group of waste positive electrode battery powders with strong oxidizability are classified as the cathode treatment mixed powder. Then, they are made into anode slurry and cathode slurry, and the anode slurry and the cathode slurry are ionized by an electrolysis device, so that the valuable metal ions in the anode slurry can be electrolytically dissociated in the anode slurry, and a small amount of water in the anode slurry can be ionized to produce H +, the electrolyte will ionize hydrogen ions. At the same time, under the action of an electric field, the valuable metal ions generated by the ionization of the anode slurry and the hydrogen ions generated by the electrolyte can migrate towards the cathode slurry. The cathode treatment mixed powder in the cathode slurry can react with the hydrogen ions, enabling the valuable metal ions in the high valence state in the cathode slurry to be reduced to the metal ions in the low valence state that are easily soluble, realizing the ionization of the valuable metal ions in the cathode slurry, enabling the valuable metal ions in the anode slurry and the valuable metal ions in the cathode slurry to be enriched in the cathode slurry, achieving the simultaneous ionization operation of various different types of waste lithium battery powders in the anode slurry and the cathode slurry, thereby realizing the efficient and comprehensive ionization of various different types of waste lithium battery powders. It is not only simple in operation, but also does not require the additional addition of other chemical reagents, effectively avoiding the introduction of new impurities, ensuring the purity of the valuable metal ions well, having low cost, being green and environmentally friendly, and having high and comprehensive ionization efficiency. It is particularly suitable for the application of doping various different types of waste battery cathode powders during the crushing process. + And the hydrogen ions generated by the electrolyte can migrate towards the cathode slurry under the action of an electric field. The cathode treatment mixed powder in the cathode slurry can react with the hydrogen ions, enabling the valuable metal ions in the high valence state in the cathode slurry to be reduced to the metal ions in the low valence state that are easily soluble, realizing the ionization of the valuable metal ions in the cathode slurry, enabling the valuable metal ions in the anode slurry and the valuable metal ions in the cathode slurry to be enriched in the cathode slurry, achieving the simultaneous ionization operation of various different types of waste lithium battery powders in the anode slurry and the cathode slurry, thereby realizing the efficient and comprehensive ionization of various different types of waste lithium battery powders. It is not only simple in operation, but also does not require the additional addition of other chemical reagents, effectively avoiding the introduction of new impurities, ensuring the purity of the valuable metal ions well, having low cost, being green and environmentally friendly, and having high and comprehensive ionization efficiency. It is particularly suitable for the application of doping various different types of waste battery cathode powders during the crushing process.

[0102] The following are some specific examples. 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 without special instructions.

[0103] Example 1

[0104] (1) Prepare 50 L of 10 g / L dilute sulfuric acid solution and pump it into the electrolytic cell through the electrolyte feed pipeline;

[0105] (2) Pulp 10 kg of waste lithium iron phosphate battery powder and water in a weight ratio of 1:1, and pump it into the anode basket through the anode feed pipeline; Pump water into the cathode basket through the cathode slurry feed pipeline;

[0106] (3) Start the Roots blower and continuously perform aeration operations on the anode basket and the cathode basket. The aeration volume is 10 m 3 / h;

[0107] (4) Start the electrolysis device: Control the voltage at 8 V, the current density at 10 A / cm 2 , the electrolysis time is 120 min, the stirring speed is 200 r / min. After electrolysis is completed, pump out the anode slurry in the anode basket and filter it to obtain the anode electrolyzed solution and the anode electrolytic slag. The cathode electrolyte is the valuable metal ion solution. Detect the anode electrolytic slag and calculate that the leaching rate of lithium is 98.1%, and the anode electrolytic slag is iron phosphate slag.

[0108] Example 2

[0109] (1) Prepare 60 L of 20 g / L dilute sulfuric acid solution and pump it into the electrolytic cell through the electrolyte feed pipeline;

[0110] (2) Pulverize 10 kg of waste lithium iron phosphate battery powder and water into a slurry at a weight ratio of 1:1, and pump it into the anode basket through the anode feed pipeline;

[0111] (3) Pulverize 10 kg of waste ternary battery powder and water into a slurry at a weight ratio of 1:1, and pump it into the cathode basket through the cathode slurry feed pipeline;

[0112] (4) Start the Roots blower and continuously aerate the anode basket and the cathode basket. The aeration volume is 15 m 3 / h;

[0113] (5) Start the electrolysis device: control the voltage at 5 V, the current density at 8 A / cm 2 , the electrolysis time is 240 min, the stirring speed is 300 r / min. After electrolysis, pump out the anode slurry in the anode basket for filtration to obtain the post - electrolysis anode solution and the anode electrolysis slag; pump out the cathode slurry in the cathode basket for filtration to obtain the post - electrolysis cathode solution and the cathode electrolysis slag. The cathode electrolyte is the valuable metal ion solution. Detect the anode electrolysis slag and the cathode electrolysis slag respectively, and calculate that the lithium leaching rate of the lithium iron phosphate battery powder is 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%.

[0114] Example 3

[0115] (1) Prepare 50 L of 40 g / L dilute sulfuric acid solution and pump it into the electrolytic cell through the electrolyte feed pipeline;

[0116] (2) Pulverize 3 kg of waste lithium iron phosphate battery powder and 3 kg of waste lithium manganese iron phosphate battery powder and water into a slurry at a weight ratio of 1:3, and pump it into the anode basket through the anode feed pipeline;

[0117] (3) Pulverize 4 kg of waste ternary battery powder and 2 kg of waste lithium cobalt oxide battery powder and water into a slurry at a weight ratio of 1:2, and pump it into the cathode basket through the cathode slurry feed pipeline;

[0118] (4) Start the Roots blower and continuously aerate the anode basket and the cathode basket. The aeration volume is 22 m 3 / h;

[0119] (5) Start the electrolysis device: control the voltage at 8 V, the current density at 20 A / cm 2, the electrolysis time was 240 min, the stirring speed was 300 r / min. After electrolysis was completed, the anode slurry in the anode basket was pumped out for filtration to obtain the post-electrolysis anode solution and the anode electrolysis residue. The cathode slurry in the cathode basket was pumped out for filtration to obtain the post-electrolysis cathode solution and the cathode electrolysis residue. The cathode electrolyte was the valuable metal ion solution. The anode electrolysis residue and the cathode electrolysis residue were respectively detected, and the lithium leaching rates of the lithium iron phosphate battery powder and the lithium manganese iron phosphate battery powder were calculated to be 98.5%. The anode electrolysis residue was the iron phosphate residue; the lithium leaching rate of the ternary battery powder and lithium cobaltate 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%.

[0120] Example 4

[0121] (1) Prepare 50 L of 40 g / L dilute sulfuric acid solution and pump it into the electrolytic cell through the electrolyte feed pipeline;

[0122] (2) Pulp 3 kg of waste lithium iron phosphate battery powder and 3 kg of waste lithium cobaltate battery powder with water in a weight ratio of 1:3, and pump it into the anode basket through the anode feed pipeline;

[0123] (3) Pulp 4 kg of waste ternary battery powder and 2 kg of waste lithium manganese iron phosphate battery powder with water in a weight ratio of 1:2, and pump it into the cathode basket through the cathode slurry feed pipeline;

[0124] (4) Start the Roots blower and continuously carry out aeration operations on the anode basket and the cathode basket, with the aeration volume being 22 m 3 / h;

[0125] (5) Start the electrolysis device: control the voltage at 8 V and the current density at 20 A / cm 2 , the electrolysis time was 10 min; the stirring speed was 300 r / min,

[0126] (6) When electrolysis was completed, swap the anode and cathode plates of the electrolysis device and continue electrolysis for 140 min. Pump out the anode slurry in the anode basket for filtration to obtain the post-electrolysis anode solution and the anode electrolysis residue; pump out the cathode slurry in the cathode basket for filtration to obtain the post-electrolysis cathode solution and the cathode electrolysis residue; the original anode electrolyte was the valuable metal ion solution. The anode electrolysis residue and the cathode electrolysis residue were respectively detected, and the lithium leaching rate of the lithium iron phosphate battery powder was calculated to be 97.6%, the lithium leaching rate of the lithium manganese iron phosphate battery powder was 98.1%, the lithium leaching rate of the ternary battery powder and lithium cobaltate was 96.2%, the nickel leaching rate was 97.9%, the cobalt leaching rate was 95.4%, and the manganese leaching rate was 96.6%.

[0127] It can be seen from the comparison between Examples 2 to 4 and Example 1 that when the method for ionizing valuable metal ions in waste lithium battery powder of the present disclosure is used to ionize various different types of waste cathode battery powder, not only is the operation simple, but also no additional chemical reagents need to be added, effectively avoiding the introduction of new impurities, well ensuring the purity of valuable metal ions, with low cost, environmental friendliness, high and comprehensive ionization efficiency. Moreover, it can be seen from Example 4 that it is still applicable to waste battery cathode powder doped with various different types of waste batteries with different properties.

[0128] The above-described embodiments only represent several embodiments of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention patent shall be subject to 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; 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; Add an electrolyte to the electrolysis device (10) so that the anodic slurry and the cathodic slurry are surrounded by the external electrolyte, and the electrolyte forms an ion conduction system with the anodic slurry and the cathodic slurry; Perform an ionization operation on the anodic slurry and the cathodic slurry through the electrolysis device (10); filter the cathodic slurry after the ionization operation to obtain a cathodic electrolyzed solution; wherein, the cathodic electrolyzed 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 separately pulping the anodic treatment mixed powder and the cathodic treatment mixed powder, the dosage ratio of the anodic treatment mixed powder and 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 1, 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.

4. 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, the following steps are further included: Crush and screen each of the waste cathode battery powders to obtain each waste cathode battery powder with a particle size ≥5um.

5. 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 ~25 A / cm 2 , and the ionization time is 20 min to 240 min.

6. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 1, characterized in that, When adding the electrolyte to the electrolysis device (10), perform a stirring operation on the electrolyte through the stirrer (800) of the electrolysis device (10).

7. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 1, 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.

8. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 1, characterized in that, The electrolyte includes at least one of dilute sulfuric acid, a sulfate system electrolyte, a chloride system electrolyte, and a nitrate system electrolyte.

9. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 8, characterized in that, The sulfate system electrolyte is a sodium sulfate solution.

10. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 8, characterized in that, The chloride system electrolyte is a sodium chloride solution.

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

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

13. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 1, characterized in that, When performing an ionization operation on the anodic slurry and the cathodic slurry through the electrolysis device (10), simultaneously perform a continuous aeration operation on the anodic slurry and the cathodic slurry.

14. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 13, characterized in that, The aeration volume of the continuous aeration operation is 20 m 3 / min to 40 m 3 / min.

15. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 1, characterized in that, The electrolysis device (10) includes an electrolytic cell (100), a power supply component (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 paste feeding pipe (620), and a cathode paste feeding pipe (630). The discharging assembly includes an electrolyte discharging pipe (710), an anode paste discharging pipe (720), and a cathode paste 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 paste feeding pipe (620) and the anode paste discharging pipe (720) are respectively communicated with the anode basket (310). The anode basket (310) is used for containing the anode paste. 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 paste feeding pipe (630) and the cathode paste discharging pipe (730) are respectively communicated with the cathode basket (410). The cathode basket (410) is used for containing the cathode paste. 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). The two aeration discs (540) of the aeration assembly are respectively arranged inside the anode basket (310) and the cathode basket (410). The two aeration discs (540) are respectively used for performing continuous aeration operations on the anode paste and the cathode paste.

16. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 15, characterized in that, The electrolysis device (10) further includes a stirrer (800). The stirrer (800) is arranged between the anode basket (310) and the cathode basket (410).

17. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 15, 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.

18. The method for extracting valuable metal ions from waste lithium battery powder according to claim 17, characterized in that, The material of the mesh plastic basket includes at least one of PP, PE, PTFE, and nylon.

19. The method for extracting valuable metal ions from waste lithium battery powder according to claim 15, characterized in that, The cathode plate (420) includes at least one of a graphite plate, a lead plate, and a titanium plate.

20. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 15, characterized in that, 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.

21. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 15, characterized in that, The aeration assembly includes a blower (510), an anode connecting pipe (520), a cathode connecting pipe (530), and the two aeration discs (540). The blower (510) is arranged outside the electrolytic cell (100). The air outlet pipe of the blower (510) is 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).

22. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 15, characterized in that, 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).

23. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 21, characterized in that, The first end of the anode connecting pipe (520) is communicated with the air outlet pipe of the blower (510), and 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).

24. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 21, wherein The first end of the cathode connecting pipe (530) is communicated with the air outlet pipe of the blower (510), and 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).

25. The method for recovering valuable metal ions from waste lithium battery powder according to claim 23 or 24, characterized in that, A bending part (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 part (550) is communicated with the aeration disc (540).

26. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 21, wherein The aperture of the air vent hole (541) is 1 mm to 5 mm.

27. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 21, characterized in that, The number of the air vent holes (541) is multiple, and the distribution of each air vent hole (541) is elliptical.

28. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 21, characterized in that, The aeration disc (540) and the anode connecting pipe (520) and / or the cathode connecting pipe (530) are connected at an inclined angle.

29. The method for extracting valuable metal ions from waste lithium battery powder according to claim 21, characterized in that, The blower (510) is a Roots blower (510).

30. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 15, 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).

31. The method for electrolyzing valuable metal ions in waste lithium battery powder according to claim 15, characterized in that, 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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