Method and apparatus for recycling mixed lithium-ion batteries

Abstract

A method includes selectively redox leaching a. black mass that has lithium battery materials with an acid and a. redox agent. The method may selectively removing titanium, copper and aluminum from a first filtrate formed from the redox leaching. The method may treat a. filtrate formed from removing the copper and the aluminum to form battery grade compounds.

Description

PATENT APPLICATION ATTORNEY DOCKET NO.19054-006WO1 METHOD AND APPARATUS FOR RECYCLING MIXED LITHIUM-ION BATTERIES BACKGROUND

[0001] Lithium-ion batteries are a type of rechargeable battery commonly used in portable electronics, electric vehicles, energy storage, and renewable energy systems. Lithium-ion batteries typically consist of an anode, usually made of graphite, a cathode composed of a lithium metal oxide, and an electrolyte that facilitates the movement of lithium ions between the electrodes. Based on the cathode materials used, lithium-ion batteries can be classified into different categories, such as lithium cobalt oxide, lithium manganese oxide, lithium titanate, lithium iron phosphate (LFP), and lithium nickel manganese cobalt (NMC or NCM) oxide batteries. Among these different categories, NMC and LFP dominate by sharing 33-40% and 30-35% of the market, respectively.

[0002] Lithium-ion battery manufacturing consumes a significant quantity of raw materials. For instance, to produce 1 kWh of LFP battery, approximately 0.3-0.4 kg of lithium carbonate, 0.8-1.0 kg of iron in the form of iron phosphate, 0.3-0.4 kg of phosphorous, 0.5-0.7 kg of graphite, 0.2-0.3 kg of electrolyte, and 0.1-0.2 kg of binder and conductive additives need to be consumed. In addition, to produce 1 kWh of NMC battery, approximately 0.5-0.6 kg of lithium carbonate, 0.5-0.7 kg of nickel, 0.3-0.4 kg of manganese, 0.1-0.2 kg of cobalt, 0.5-0.7 kg of graphite, 0.2-0.3 kg of electrolyte, and 0.1- 0.2 kg of binder and conductive additives need to be consumed. These raw materials represent not only a significant cost but also substantial carbon emissions associated with battery manufacturing. Therefore, it is essential to develop technologies for sustainable lithium-ion battery recycling.

[0003] Unfortunately, most existing recycling technologies only focus on the recycling of a single type of lithium-ion batteries, due to chemical composition variations, process complexity, economic viability, and regulatory and safety considerations. However, in many cases, different types of lithium-ion batteries are mixed together after they are retired or recycled. This mixing can occur due to several reasons: (1) Collection method - Batteries from various sources, such as consumer electronics, electric vehicles, and energy storage systems, may be collected together without initial sorting based on batteryPATENT APPLICATION ATTORNEY DOCKET NO.19054-006WO1 chemistry; (2) Recycling facilities - Recycling facilities may receive batteries in mixed batches, especially from collection centers or waste management facilities that gather batteries from diverse sources; (3) Handling practices - During transportation and processing, batteries may become mixed due to handling practices or storage conditions; and (4) Economic considerations: Sorting batteries by chemistry can add complexity and cost to the recycling process, and thus, some facilities may opt for bulk processing without initial separation.

[0004] Therefore, it is necessary to develop technologies that have a certain degree of flexibility and can process single or mixed batteries, such as lithium cobalt oxide (LCO), lithium manganese oxide (LMO), lithium nickel cobalt manganese (NMC or NCM), lithium iron phosphate (LFP) lithium nickel manganese spinel (LNMO), lithium nickel cobalt aluminum oxide (NCA), lithium manganese iron phosphate (LFMP), and lithium manganese phosphate (LMP) batteries, particularly mixed NMC and LFP / LFMP batteries due to their significant market shares. This present invention addresses these, and other problems associated with the prior art. SUMMARY

[0005] This summary is provided to introduce a selection of concepts that are further described below in the detailed description. This summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used as an aid in limiting the scope of the claimed subject matter.

[0006] In some aspects, the techniques described herein relate to a method for recycling spent or scrap lithium battery materials including: selectively redox leaching a black mass including lithium battery materials with an acid and a redox agent; selectively removing titanium, copper and aluminum from a first filtrate formed from the redox leaching; and treating a filtrate formed from removing the copper and the aluminum to form battery grade compounds.

[0007] In some aspects, the techniques described herein relate to a method, further including, before the selectively redox leaching the black mass, selectively acid leaching the black mass with an acid.PATENT APPLICATION ATTORNEY DOCKET NO.19054-006WO1

[0008] In some aspects, the techniques described herein relate to a method, further including, after selectively acid leaching: removing titanium from a filtrate formed from acid leaching; removing copper from a filtrate formed from removing the titanium; removing aluminum from a filtrate formed from removing the copper; and precipitating a crude iron phosphate from a filtrate formed from removing the aluminum.

[0009] In some aspects, the techniques described herein relate to a method, further including, after the precipitating the crude iron phosphate: adjusting a pH of a filtrate formed from precipitating the crude iron phosphate, with a base or precipitant to a range of about 4 to about 10 to remove contaminants; separating a crude lithium carbonate; and precipitating battery grade lithium carbonate from a filtrate formed from separating the crude lithium carbonate.

[0010] In some aspects, the techniques described herein relate to a method, wherein the precipitating the battery grade lithium carbonate includes: iteratively performing mechanical vapor recompression on the filtrate formed from separating the crude lithium carbonate; and precipitating and refining the battery grade lithium carbonate from a concentrated filtrate formed from iteratively performing mechanical vapor recompression.

[0011] In some aspects, the techniques described herein relate to a method, further including, after the adjusting a pH of a filtrate formed from precipitating the crude iron phosphate, feeding the formed contaminants with a solid formed from acid leaching to the selective redox leaching to form a second filtrate.

[0012] In some aspects, the techniques described herein relate to a method, further including, after feeding the formed contaminants with the solid formed from acid leaching to selectively redox leaching: removing impurities from the second filtrate formed from the redox leaching; sequentially extracting a filtrate formed from removing the impurities to remove Li, Mn, Co and Ni into respective individual steams; and crystallizing respective individual streams to form their respective battery grade compounds.

[0013] In some aspects, the techniques described herein relate to the method of any one of the above claims, wherein the selectively removing copper from the first filtrate formedPATENT APPLICATION ATTORNEY DOCKET NO.19054-006WO1 from the redox leaching includes at least one of: treating the first filtrate formed form the redox leaching with a base to adjust a pH of the first filtrate, adding iron powder to the first filtrate formed form the redox leaching, performing selective adsorption or extracting copper with a solvent or combinations thereof; or separating the filtrate formed from removing the copper.

[0014] In some aspects, the techniques described herein relate to a method, wherein the removing the copper and the aluminum from the first filtrate formed from the redox leaching includes at least one of: selectively precipitating aluminum by adding a precipitant or complexing agent; or performing selective ion exchange on the filtrate formed from removing the copper.

[0015] In some aspects, the techniques described herein relate to a method, wherein the complexing agent is selected from the group consisting of an alkali metal compound, a fluoride compound capable of complexing with aluminum, oxalic acid, diethylenetriaminepentaacetic acid, and combinations thereof.

[0016] In some aspects, the techniques described herein relate to a method, wherein the fluoride compound is selected from the group consisting of sodium fluoride, potassium fluoride, sodium fluoride, lithium fluoride, and combinations thereof.

[0017] In some aspects, the techniques described herein relate to a method, wherein the treating the filtrate formed from removing the copper and the aluminum to form battery grade compounds includes: sequentially extracting the filtrate formed from removing the copper and the aluminum to remove Li, Mn, Co and Ni into respective individual steams; and processing respective individual streams to form respective battery grade compounds.

[0018] In some aspects, the techniques described herein relate to a method, further including, after redox leaching the black mass: acid leaching a solid formed from redox leaching the black mass; removing impurities from a filtrate formed from the acid leaching the solid; oxidizing a filtrate formed from removing impurities from a filtrate formed from the acid leaching the solid; and precipitating iron phosphate from a filtrate formed from oxidizing the filtrate.PATENT APPLICATION ATTORNEY DOCKET NO.19054-006WO1

[0019] In some aspects, the techniques described herein relate to a method, wherein the acid for acid leaching and / or redox leaching is selected from inorganic acids, organic acids or mixtures thereof.

[0020] In some aspects, the techniques described herein relate to a method, wherein the redox agent is selected from the group consisting of hydrogen peroxide, oxygen, ozone, potassium iodide, and combinations thereof.

[0021] Other aspects and advantages of the claimed subject matter will be apparent from the following description and the appended claims. BRIEF DESCRIPTION OF THE FIGURES

[0022] The Figure is a process flow diagram in accordance with one or more embodiments. DETAILED DESCRIPTION

[0023] The disclosure is not limited to particular embodiments described, and as such may, of course, vary. The terminology used herein serves the purpose of describing particular embodiments only, and is not intended to be limiting, since the scope of the present disclosure will be limited only by the appended claims.

[0024] As those having ordinary skill in the art will appreciate, different persons may refer to the same feature by different names. This document does not intend to distinguish between features that differ in name but not function. The figures are not necessarily drawn to scale. Certain features here may be shown in somewhat schematic form and some details may not be shown in the interest of clarity and conciseness.

[0025] Those having ordinary skill in the art will appreciate that the following description has broad application, and the discussion of any embodiment is meant only to be exemplary of that embodiment, and not intended to suggest that the scope of the disclosure, including the claims, is limited to that embodiment.

[0026] While aspects of the present disclosure can be described and claimed in a particular statutory class, such as the system statutory class, this is for convenience only and one of skill in the art will understand that each aspect of the present disclosure can be described and claimed in any statutory class.PATENT APPLICATION ATTORNEY DOCKET NO.19054-006WO1

[0027] Embodiments of the present disclosure will employ, unless otherwise indicated, techniques of organic chemistry, inorganic chemistry, biology, and the like, which are within the skill of the art. Such techniques are explained fully in the literature.

[0028] The following examples are put forth so as to provide those of ordinary skill in the art with a complete disclosure and description of how to perform the methods and use the compositions and compounds disclosed and claimed herein. Effects have been made to ensure accuracy with respect to numbers (e.g., amounts, temperatures, etc.), but some errors and deviations should be accounted for.

[0029] Before the embodiments of the present disclosure are described in detail, it is to be understood that, unless otherwise indicated, the present disclosure is not limited to particular materials, reagents, reaction materials, manufacturing processes, dimensions, frequency ranges, applications, or the like, as such can vary. It is also to be understood that the terminology used herein is for purposes of describing particular embodiments only and is not intended to be limiting. It is also possible in the present disclosure that steps can be executed in different sequence, where this is logically possible. It is also possible that the embodiments of the present disclosure can be applied to additional embodiments involving measurements beyond the examples described herein, which are not intended to be limiting. It is furthermore possible that the embodiments of the present disclosure can be combined or integrated with other measurement techniques beyond the examples described herein, which are not intended to be limiting.

[0030] As used in the discussion and the appended claims, the singular form “a,” “an” and “the” include plural referents unless the context clearly dictates otherwise. For example, reference to “a solvent extraction system,” “an oxidizing agent,” or “the black mass material” includes, but is not limited to, two or more such solvent extraction systems, oxidizing agents, or black mass materials, and the like.

[0031] As used herein, the term “and / or” includes any and all combinations of one or more of the associated listed items.

[0032] It should be noted that ratios, temperatures, pH values, and other numerical data can be expressed herein in a range format. It will be further understood that the end pointsPATENT APPLICATION ATTORNEY DOCKET NO.19054-006WO1 of each of the ranges are significant both in relation to the other endpoint, and independently of the other endpoint. It will be also understood that there are a number of values disclosed herein, and that each value is also herein disclosed as “about” that particularly value in addition to the value itself. For example, if the value “60” is disclosed, then “about 60” is also disclosed. Ranges can be expressed herein as from “about” one particular value, and / or to “about” another value. Similarly, when values are expressed as approximations, by the use of the antecedent “about”, it will be understood that the particular value forms a further aspect. For example, if the value “about 60” is disclosed, then “60” is also disclosed.

[0033] When a range is expressed, a further aspect includes from one particular value and / or to the other particular value. For example, where the stated range includes one or both of the limits, ranges excluding either or both of those included limits are also included in the disclosure, e.g., the phrase “x to y” includes the range from “x” to “y” as well as the ranges greater than “x” and less than “y”. In addition, the phrase “about x to y”, where “x” and “y” are numerical values, includes “about x” to “about y.”

[0034] It is to be understood that such a range format is used for convenience and brevity, and thus, should be interpreted in a flexible manner to include not only the numerical values explicitly recited as the limits of the range, but also to include all the individual numerical values or sub-ranges encompassed within that range as if each numerical value and sub-range is explicitly recited. To illustrate, a concentration range of “about 0.1 percent to 0.5 percent” should be interpreted to include not only the explicitly recited concentration of about 0.1 percent to about 0.5 percent but also include individual concentrations (e.g., 1 percent, 2 percent, 3 percent, and 4 percent) and the sub-ranges (e.g., 0.5 percent, 1.1 percent, 2.2 percent, 3.3 percent, and 4.4 percent) within the indicated range. The term “about” can include traditional rounding according to significant figures of the numerical value. In addition, the phrase “about ‘x’ to ‘y’” includes “about ‘x’ to ‘about y’”.

[0035] Furthermore, the terms “about,” “several,” “multiple,” “a number of,” “some,” “at or about,” “substantially,” “mainly,” “primarily,” and “minimal” as used herein mean that the amount or value in question can be the exact value or a value that provides equivalentPATENT APPLICATION ATTORNEY DOCKET NO.19054-006WO1 results or effects as recited in the claims or taught herein. That is, it is understood that amounts, sizes, formulations, parameters, and other quantities and characteristics are not and need not to be exact but may be approximate and / or larger or smaller, as desired, reflecting tolerances, conversion factors, rounding off, measurement error and the like, and other factors known to those of skill in the art such that equivalent results or effects are obtained. In some circumstance, the value that provides equivalent results or effects cannot be reasonable determined. In such cases, it is generally understood, as used herein, that “about” and “at or about” mean the nominal value indicated 10% variations unless otherwise indicated or inferred. In general, an amount, size, formulation, parameter or other quantity or characteristic is “about,” “several,” “multiple,” “a number of,” “some,” “at or about,” “substantially,” “mainly,” “primarily,” and “minimal” whether or not expressly stated to be such. It is understood that where “about” or “at or about” is used before a quantitative value, the parameter also includes the specific quantitative value itself, unless specifically stated otherwise.

[0036] In the following discussion and in the claims, the terms “such as”, “including” and “comprising” are used in an open-ended fashion, and thus should be interpreted to mean “including, but not limited to ....”

[0037] As used herein, “contaminants” or “impurities” refers to undesired materials in the final products. Contaminants and impurities include, but are not limited to aluminum, copper, calcium, magnesium, titanium, silicon, zinc, sulfur, and fluoride.

[0038] As used herein, “valuable constituents” refers to the desired materials, including but not limited to lithium, nickel, cobalt, manganese, iron, and phosphorus.

[0039] As used herein, “crude” refers to the purity of the products may be low, and further refinement may be required to make them suitable for battery manufacturing.

[0040] As used herein, “battery-grade” refers to the purity and other specifications of the products meet the standards of being used for battery manufacturing.

[0041] As used herein, “relative pure water” refers to there are no undesired constituents that will affect product purity in the water.PATENT APPLICATION ATTORNEY DOCKET NO.19054-006WO1

[0042] Referring to The Figure, a process flow diagram in accordance with embodiments disclosed herein is shown. This process is referred to as an LFP / LFMP preferential leaching process since iron, phosphorus, and lithium are primarily leached in the first leaching step, while nickel, cobalt, and manganese are primarily leached in the second leaching step.

[0043] The method and apparatus disclosed herein for lithium-ion battery recycling applies to both spent batteries and scraps 102 generated from lithium-ion battery manufacturing. These lithium-ion batteries may consist of only NMC batteries or a combination of two or more types of batteries (i.e., LCO, LMO, NMC, LFP, LNMO, NCA, LMFP, LMP). The batteries may be discharged before proceeding next. A material that is normally referred to as black mass (BM) and contains mainly the cathode and anode materials may be produced by crushing, shredding and separation, or other methods 102. Depending on the battery types in the mixture, the resulting black mass material may have different elemental compositions, such as Li 0-20%, Ni 0-100%, Co 0-100%, Mn 0-100%, Al 0- 100%, P 0-100%, and Fe 0-100%.

[0044] Those having ordinary skills in the art will appreciate that the recycled batteries may come in the form of black mass already. In this case, the step of cruising, shredding and sieving 102 may not be necessary.

[0045] Embodiments disclosed herein are directed to a method that can be used to recycle both lithium nickel manganese cobalt oxide batteries and a mixture of two or more different types of batteries. The black mass material 102 is subjected to leaching 104 to dissolve the valuable constituents, along with some contaminants. In one aspect, if the black mass material 102 originates from only lithium nickel manganese cobalt oxide batteries, the material may be directly fed to reductive acid leaching 118 followed by downstream steps 120-128. In another aspect, if the black mass material 102 originates from a mixture of two or more different types of, the material may be fed to leaching 104.

[0046] The black mass material 102 is reacted with an acid solution in leaching 104 under appropriate conditions in the absence of reducing agents. This step may be performed to selectively leach Li, Fe, and P from the lithium battery materials. In one aspect, the favorable final pH after leaching ranges from about 0.01 to about 2.0. In another aspect,PATENT APPLICATION ATTORNEY DOCKET NO.19054-006WO1 the acid used can be H2SO4, HCl, HNO3, H3PO4, or a combination of these. Solid / liquid separation may be conducted after leaching to separate liquids from solids. Any solid / liquid separation methods, such as filter press, may be used for this purpose. The resulting liquid may be referred to as filtrate, leachate, or solution in the following discussion and in the claims. The solid after the separation may be referred to as filter cake, leaching residue, precipitates, or simply solid in the following discussion and in the claims. After solid / liquid separation, the filtrate containing lithium, nickel, cobalt, manganese, iron, phosphorous, and some contaminants as well as the solid containing remaining valuable constituents and contaminants are collected and further processed as discussed next. The filter cake may be washed several time using an appropriate solution, such as deionized water, to collect the leachate entrapped in the capillary tubes within the particles in the filter cake.

[0047] After solid / liquid separation, the filtrate is further processed to remove titanium, copper and aluminum. While the figure shows titanium removal followed by copper and aluminum removal, these removal steps may be performed in a different order.

[0048] The filtrate obtained from processes 104 and 204 may be subjected to titanium removal process 105 and 205 to reduce or eliminate Ti. To achieve efficient removal, the pH of the filtrates may be raised / adjusted to a pH ranging from 1 to 3, such as from a lower limit of any one of 1.0, 1.2, or 1.4 to an upper limit of any one of 2, 2.2, 2.5, 2.8 or 3, where any lower limit may be paired with any mathematically compatible upper limit. The pH may be adjusted by adding a carbonate base such as sodium carbonate. The reaction for titanium removal may occur for at least 1 hour and up to 12 hours, and at a temperature ranging from about 20 °C to about 60 °C.

[0049] The filtrate obtained from leaching and filtration 104 may be fed to de-Cu 106 to eliminate Cu from the solution. In the de-Cu step, the pH of the filtrate may be raised first by adding a base, such as NaOH, KOH, and Na2CO3, K2CO3. After reaching the desired pH, Cu can be removed by adding iron powder, which serves as a reducing agent to convert Cu from its ionic to metallic form. To achieve efficient removal, the pH of the filtrates for de-Cu may be raised / adjusted to a pH ranging from 1 to 3, such as from a lower limit of any one of 1.0, 1.3, 1.5 or 2 to an upper limit of any one of 2.2, 2.5, 2.8 orPATENT APPLICATION ATTORNEY DOCKET NO.19054-006WO1 3, where any lower limit may be paired with any mathematically compatible upper limit. In one or more embodiments, the de-Cu step using iron powder occurs at a temperature ranging from about 20 °C to about 100 °C. In such embodiments, the dosage of iron powder is expected to be 10-50% extra of theoretical amount. As a non-limiting example, iron powder may be added into the leaching solution at a reaction temperature of 50 °C. The suspension may be continuously stirred during the reaction, while the dosage of iron powder is maintained at a stoichiometric ratio to Cu ranging from 1:1 to 10:1. Subsequently, solid / liquid separation may be conducted after reduction to separate liquids from solids. Any solid / liquid separation methods, such as filter press, may be used for this purpose. After solid / liquid separation, the filtrate containing valuable constituents and contaminants, but minimal Cu, is collected and further processed as discussed next. The filter cake may be washed several times using an appropriate solution, such as deionized water, to collect the leachate entrapped in the capillary tubes within the particles in the filter cake. Those having ordinary skills in the art will appreciate that other methods, such as selective adsorption, can be applied to eliminate Cu from the solution in the de-Cu step 106.

[0050] The filtrate obtained from de-Cu 106 may be fed to de-Al 108 to eliminate Al from the solution. Selective precipitation by adding a precipitant, which includes, but is not limited to, Na2CO3, NaF, KF, LiF, oxalic acid, diethylenetriaminepentaacetic acid, and other complexing agents, may be used to eliminate Al. The pH of the leachate may be adjusted by adding bases complexing agents to precipitate aluminum. To achieve efficient removal, the pH of the filtrates for de-Al may be raised / adjusted to a pH ranging from 1 to 3, such as from a lower limit of any one of 1.0, 1.2 or 1.4 to an upper limit of any one of 1.5, 1.7, 1.9 or 2, where any lower limit may be paired with any mathematically compatible upper limit. The resulting slurries may be then filtered or use other methods to separate the precipitates and the liquid. After solid / liquid separation, the filtrates are collected and will be processed next, while the filter cake mainly contains aluminum precipitates. The de-Al efficiency of the process may be determined by several factors, such as reaction temperature, leachate pH, complexing agent types and dosage, complexing reaction conditions, and rinsing.PATENT APPLICATION ATTORNEY DOCKET NO.19054-006WO1

[0051] The complexing agents may be a mixture of alkali metal compounds and fluoride compounds. Alkali metal compounds provide metal ions to complexes, while fluoride ions selectively complex with aluminum. In one or more embodiments, the alkali metal compounds that may be used in this application include but are not limited to sodium hydroxide, sodium carbonate, sodium sulfate, potassium hydroxide, potassium carbonate, potassium sulfate, ammonia, and iron powder. In a further aspect, the fluoride compounds that may be used include but are not limited to sodium fluoride, potassium fluoride, ammonium fluoride and lithium fluoride. A variety of complexing agents may be obtained by mixing one or multiple alkali metal compounds and fluoride compounds. In addition, alkali metals introduced in previous steps of the process may also participate in the complexation reaction as reactants. The de-Al can also be conducted by using the selective ion exchange method.

[0052] Subsequently, solid / liquid separation may be conducted to separate liquids from solids. Any solid / liquid separation methods, such as filter press, may be used for this purpose. After solid / liquid separation, the filtrate containing valuable constituents and contaminants, but minimal Cu and Al, is collected and further processed as discussed next. The filter cake may be washed several times using an appropriate solution, such as deionized water, to collect the leachate entrapped in the capillary tubes within the particles in the filter cake. Those having ordinary skills in the art will appreciate that other methods, such as selective adsorption, can be applied to eliminate Al from the solution in the de-Al step 108.

[0053] The filtrate obtained from de-Al 108 is fed to iron phosphate (FP) precipitation and separation 110. In this step, the valence state of iron may be changed from 2+ to 3+ by adding an oxidizing agent, such as hydrogen peroxide and ozone. In the meantime, the pH of the filtrate may be maintained in the range of about 0.5 to about 3.0, leading to the production of a crude FP product. Subsequently, solid / liquid separation may be conducted to separate the solid product and the liquid. Any solid / liquid separation methods, such as filter press, may be used for this purpose. After solid / liquid separation, the filtrate containing valuable constituents and contaminants, but minimal Cu, Al, Fe, and phosphorous, is collected and further processed as discussed next. The filter cake may bePATENT APPLICATION ATTORNEY DOCKET NO.19054-006WO1 washed several times using an appropriate solution, such as deionized water, to collect the leachate entrapped in the capillary tubes within the particles in the filter cake.

[0054] The lithium-rich solution 114 obtained from FP precipitation and separation 110 is further subjected to staged precipitation and separation 116 by increasing the pH with the addition of a base and / or other precipitants, including but not limited to NaOH, Na2CO3, ammonia, and CaO. The staged precipitation and filtration may be used to further remove / precipitate metal ion contaminants including but not limited to Ni, Co, Mn and some remaining contaminants Cu, Al, Ca. The precipitates formed in the pH range of about 4.0 to about 10.0 may be collected while those formed in the other pH ranges, such as about 3.0 to about 4.0 and about 10.0 to about 14.0, may be rejected by solid / liquid separation. Any solid / liquid separation methods, such as filter press, may be used for this purpose. After solid / liquid separation, the filtrate is subjected to Li2CO3 precipitation 128 to obtain battery-grade Li2CO3. In this step, the filtrate may be concentrated and precipitated iteratively through mechanical vapor recompression (MVR) and carbonate precipitation. The purity of the crude lithium carbonate product may be enhanced to battery grade through carbonate refinement.

[0055] The filter cake of contaminants obtained in the pH range of about 4.0 to about 10.0 from the staged precipitation & separation 116 is mixed with the filter cake obtained from leaching & filtration 104. The mixture is fed to reductive acid leaching 118 in the presence of a reducing agent, including but not limited to hydrogen peroxide, SO2, Na2SO3, NaS2O4. Reductive acid leaching may be performed to non-selectively leach all contaminants in a black mass or the remaining contaminants, such as Ni, Co and Mn, present in the filter cake formed from staged precipitation 116. In one aspect, the acid used for this step includes, but is not limited to, H2SO4, HCl, HNO3 and H3PO4. In another aspect, the final pH after leaching ranges from about 0.1 to about 3.0. After reaction for a certain period, solid / liquid separation may be conducted to separate liquids from solids. Any solid / liquid separation methods, such as filter press, may be used for this purpose. The filtrate after solid / liquid separation contains lithium, nickel, cobalt, manganese, and contaminants and is further processed as discussed next. The filter cake may be washedPATENT APPLICATION ATTORNEY DOCKET NO.19054-006WO1 several times using an appropriate solution, such as deionized water, to collect the leachate entrapped in the capillary tubes within the particles in the filer cake.

[0056] The filtrate obtained from reductive acid leaching & filtration 118 is subjected to impurity removal 120 to eliminate contaminants from the filtrate. In one aspect, the impurities may be removed by increasing pH with the addition of a base, such as NaOH, KOH, black mass, and a mixture thereof. Those having ordinary skills in the art will appreciate that the impurities may be removed using other methods, such as selective precipitation, ion-exchange, and membrane-based technologies. After impurity removal, the filtrate may primarily contain valuable constituents, including nickel, cobalt, manganese, and lithium, as well as some major contaminants, including sodium and sulfate.

[0057] The filtrate after impurity removal 120 is fed to a solvent extraction system, which may include a Mn solvent extraction line 122, a Co solvent extraction line 124, and a Ni extraction line 126. Each line may include a number of stages to achieve a desired purity. Various extractants with different extraction capacities for the valuable and contaminant metal ions can be used in these steps, such as P507 ((2-ethylhexyl) phosphate), P204 (bis(2-ethylhexyl) phosphate), and C272 (bis(2,4,4-trimethylpentyl) phosphonic acid). Solutions containing nickel, cobalt, manganese, and lithium may be individually generated from the solvent extraction system. The solutions may also contain sodium and sulfate. The nickel, cobalt, and manganese solutions may be processed through crystallization to obtain battery-grade nickel, cobalt, and manganese sulfate products. The lithium solution may be fed to Li2CO3 precipitation 128 to produce battery-grade Li2CO3. In this step, the solution may be concentrated and precipitated iteratively through MVR and carbonate precipitation. The purity of the crude lithium carbonate product may be enhanced to battery grade through carbonate refinement.

[0058] Referring to The Figure, a process flow diagram 100 in accordance with embodiments disclosed herein is shown. This process is referred to as an NCM preferential leaching process since lithium, nickel, cobalt, and manganese are leached in the first leaching step while only iron and phosphorous are leached in the second leaching step.PATENT APPLICATION ATTORNEY DOCKET NO.19054-006WO1

[0059] The method and apparatus disclosed herein for lithium-ion battery recycling applies to both spent lithium-ion batteries and scraps 202 generated from lithium-ion battery manufacturing. These lithium-ion batteries may consist of only NMC batteries or a combination of two or more types of batteries (i.e., LCO, LMO, NMC, LFP, LNMO, NCA, LMFP, LMP). The batteries may be discharged before proceeding next. Black mass containing mainly the cathode and anode materials may be produced by crushing, shredding and separation, or other methods 202. Those having ordinary skills in the art will appreciate that the recycled batteries may come in the form of black mass already. In this case, the step of cruising, shredding and sieving 202 may not be necessary.

[0060] Embodiments disclosed herein are directed to a method that can be used to recycle both lithium nickel manganese cobalt oxide batteries and a mixture of two or more different types of batteries. The black mass material 202 is subjected to leaching 204 to dissolve the valuable constituents, along with some contaminants. In one or more embodiments, if the black mass material 202 originates from only lithium nickel manganese cobalt oxide batteries, the material may be fed to redox acid leaching 204 followed by downstream steps 206-216. In some embodiments, if the black mass material 202 originates from a mixture of two or more different types of batteries, the material may be fed to redox acid leaching 204 followed by downstream steps 206-224.

[0061] The black mass material 202 is subjected to redox acid leaching 204 to dissolve lithium, nickel, cobalt, and manganese, along with some contaminants. The acid used in this step can be inorganic, organic, or a mixture of both. The chemical used to serve reducing and oxidizing functions may be a single chemical with different functions for different cathode materials or a combination of a reducing and an oxidizing agent. Those redox chemicals include but are not limited to hydrogen peroxide, oxygen, ozone, and potassium iodide. After redox acid leaching under appropriate conditions, solid / liquid separation may be conducted to separate liquids from solids. Any solid / liquid separation methods, such as filter press, may be used for this purpose, leading to a filtrate containing lithium, nickel, cobalt, manganese, and some contaminants as well as a filter cake containing iron, phosphorous, and some contaminants. The filtrate and filter cake are further processed as discussed next.PATENT APPLICATION ATTORNEY DOCKET NO.19054-006WO1

[0062] Similar to 105 in The Figure, the filtrate obtained from redox leaching and filtration 204 may be subjected to titanium removal process 205 to eliminate Ti. To achieve efficient removal, the pH of the filtrates may be raised / adjusted to a pH ranging from 1 to 3, such as from a lower limit of any one of 1.0, 1.2, or 1.4 to an upper limit of any one of 2, 2.2, 2.5, 2.8 or 3, where any lower limit may be paired with any mathematically compatible upper limit. The pH may be adjusted by adding a carbonate base such as sodium carbonate. The reaction for titanium removal may occur for at least 1 hour and up to 12 hours, and at a temperature ranging from about 20 °C to about 60 °C.

[0063] The filtrate obtained from leaching and filtration 104 may be fed to the de-Cu step 206. In the de-Cu step, the pH of the filtrate may be raised first by adding a base, such as NaOH, KOH, and Na2CO3, K2CO3. After reaching the desired pH, Cu can be removed by adding iron powder, which serves as a reducing agent to convert Cu from its ionic to metallic form. Subsequently, solid / liquid separation may be conducted after reduction to separate liquids from solids. Any solid / liquid separation methods, such as filter press, may be used for this purpose. After solid / liquid separation, the filtrate containing valuable constituents and contaminants, but minimal Cu, is collected and further processed as discussed next. The filter cake may be washed several times using an appropriate solution, such as deionized water, to collect the leachate entrapped in the capillary tubes within the particles in the filter cake. Those having ordinary skills in the art will appreciate that other methods, such as selective adsorption, can be applied to eliminate Cu from the solution in the de-Cu step 206.

[0064] Similar to 108 in The Figure, the filtrate after de-Cu 206 is subjected to de-Al 208 to eliminate Al from the solution. Selective precipitation by adding a precipitant, which includes but not limited to NaOH, Na2CO3, and complexing agents, may be used to eliminate Al. Subsequently, solid / liquid separation may be conducted to separate liquids from solids. Any solid / liquid separation methods, such as filter press, may be used for this purpose. After solid / liquid separation, the filtrate containing valuable constituents and contaminants, but minimal Cu and Al, is collected and further processed as discussed next. The filter cake may be washed several times using an appropriate solution, such as deionized water, to collect the leachate entrapped in the capillary tubes within thePATENT APPLICATION ATTORNEY DOCKET NO.19054-006WO1 particles in the filter cake. Those having ordinary skills in the art will appreciate that other methods, such as selective adsorption, can be applied to eliminate Al from the solution in the de-Al step 208.

[0065] Similar to 122, 124, 126, and 128 in The Figure, the filtrate after de-Al 208 is fed to a solvent extraction system, which may include a Mn solvent extraction line 210, a Co solvent extraction line 212, and a Ni extraction line 214. Each line may include a number of stages to achieve a desired purity. Various extractants with different extraction capacities for the valuable and contaminant metal ions can be used in these steps, such as P507 ((2-ethylhexyl) phosphate), P204 (bis(2-ethylhexyl) phosphate), and C272 (bis(2,4,4-trimethylpentyl) phosphonic acid). Solutions containing nickel, cobalt, manganese, and lithium may be individually generated from the solvent extraction system. The solutions may also contain sodium and sulfate. The nickel, cobalt, and manganese solutions may be processed through crystallization to obtain battery-grade nickel, cobalt, and manganese sulfate products. The lithium solution may be fed to Li2CO3 precipitation 216 to produce battery-grade Li2CO3. In this step, the solution may be concentrated and precipitated iteratively through MVR and carbonate precipitation. The purity of the crude lithium carbonate product may be enhanced to battery grade through carbonate refinement.

[0066] As mentioned above, if the black mass material 202 originates from a mixture of two or more different types of batteries, the downstream process may include steps 218- 224. In particular, the filter cake obtained from redox leaching and filtration 204 is fed a second step of leaching and filtration 218. The iron and phosphorous present in the filter cake may be dissolved by reacting with an acid solution, such as a sulfuric acid solution, under appropriate conditions. After leaching, solid / liquid separation may be conducted to separate liquids from solids. Any solid / liquid separation methods, such as filter press, may be used for this purpose, leading to a filtrate containing iron, phosphorous, and some contaminants. The filtrate is further processed as discussed next.

[0067] Similar to de-Cu 206 and de-Al 208, as well as impurity removal 120 in The Figure, the filtrate is sent to impurity removal 220. The impurities may be removed throughPATENT APPLICATION ATTORNEY DOCKET NO.19054-006WO1 different methods, such as adding iron powder, raising the pH, introducing precipitants, and employing adsorbents for adsorption.

[0068] Similar to 110, the filtrate after impurity removal 220 is sent to FP precipitation and separation 222. In this step, the valence state of iron may be changed from 2+ to 3+ by adding an oxidizing agent, such as hydrogen peroxide and ozone. In the meantime, the pH of the filtrate may be maintained in the range of about 1.0 to about 3.0, leading to the production of a crude FP product. Subsequently, solid / liquid separation may be conducted to separate the solid product and the liquid. Any solid / liquid separation methods, such as filter press, may be used for this purpose. The filter cake may be washed several times using an appropriate solution, such as deionized water, to remove solutions containing impurities entrapped in the capillary tubes within the particles in the filter cake.

[0069] Example 1 – LFP / LFMP Preferential Leaching

[0070] 1 kg of black mass with elemental composition shown in Table 1 was mixed with 4 L dezionized water in a tank equipped with overhead stirrer. 95% sulfuric acid was added to the suspension to reduce the pH 0.2. Afterward, the suspension was heated to 70 °C, and the reaction lasted for 2 hours. After reaction, the suspension was filtered using a filter press, leading to the first filter cake and the first filtrate.

[0071] The first filtrate was transferred to a tank reactor equipped with an overhead stirrer. calcium fluoride was added into the filtrate at a dosage of 100 g per liter of filtrate. After reacting for 30 min, the resulting suspension was filtered using a press filter, leading to the second filter cake and the second filtrate.

[0072] Ozone with 30% concentration was added into the second filtrate. Afterwards, the filtrate was heated to 70 °C. After reacting for 4 hours at this temperature, the resulting suspension was filtered using a press filter, leading to the third filter cake and the third filtrate. The third filter cake is a crude iron phosphate product. The pH of the third filtrate was first raised to 12 by using NaOH, leading to the formation of some precipitates. The resulting suspension was filtered using a press filter, leading to the fourth filter cake and the fourth filtrate.PATENT APPLICATION ATTORNEY DOCKET NO.19054-006WO1

[0073] The first filter cake was mixed with the fourth filter cake in a tank equipped with an overhead stirrer. Approximately 3 liters of deionized water were added into the tank. SO2 was purged into the tank for 2h. At the same time, sulfuric acid of 95% concentration was added into the tank to drop the pH to 1.0. The suspension was heated to 70 °C, and the reaction was allowed to proceed for 2 hours. Afterwards, the suspension was filtered using a filter press, leading to the fifth filter cake and the fifth filtrate. The filtrate was purified by adding iron powder to remove copper and adjusting the pH to 4.5 to remove aluminum by adding NaOH.

[0074] The fifth filtrate after impurity removal is fed to a solvent extraction system, consisting of a Mn line, a Co line, and a Ni line. Commercial extractants, di(2- ethylhexyl)phosphoric acid (P204), mono(2-ethylhexyl) 2-ethylhexyl phosphonate (P507), and diisooctylphosphinic acid (C272), were used respectively, leading to a purified Mn sulfate solution, a purified Co sulfate solution, a purified Ni sulfate solution, and a purified Li sulfate solution. The Li sulfate solution was mixed with the fifth filtrate, and sodium carbonate was added into the mixed solution, leading to the formation of a crude lithium carbonate. The crude lithium carbonate was re-dissolved by introducing carbon dioxide. The undissolved material was removed by filtration. The resulting filtrate was evaporated, resulting in a battery-grade lithium carbonate. Elemental compositions of the lithium carbonate are shown in Table 2. The Mn, Co, and Ni sulfate solutions were fed to mechanical vapor recompression units to crystallize, resulting in battery-grade Mn, Co, and Ni sulfate products. Elemental compositions of the products are shown in Tables 3-5.PATENT APPLICATION ATTORNEY DOCKET NO.19054-006WO1 Table 1. Elemental compositions of the black mass.Note: N.D – not detected.PATENT APPLICATION ATTORNEY DOCKET NO.19054-006WO1 Table 2. Elemental compositions of the lithium carbonate product.Note: N.D – not detected. Table 3. Elemental compositions of the MnSO4·7H2O product.Note: N.D – not detected.PATENT APPLICATION ATTORNEY DOCKET NO.19054-006WO1 Table 4. Elemental compositions of the NiSO4·7H2O product.Note: N.D – not detected.PATENT APPLICATION ATTORNEY DOCKET NO.19054-006WO1 Table 5. Elemental compositions of the CoSO4·7H2O product.Note: N.D – not detected.

[0075] In one aspect, embodiments disclosed herein relate to a method a process based on LFP preferential leaching for the recycling of lithium nickel manganese cobalt oxide (NMC) batteries or a combination of two or more different types of batteries (i.e., LCO, LMO, NMC, LFP, LNMO, NCA, LMFP, LMP), the process including: discharging, dismantling, crushing / shredding, sieving / sorting, and thermally treating mixed batteries, as well as the scraps generated during lithium-ion battery manufacturing processes, leading to a black mass material that contains anode and cathode materials along with some contaminants; leaching the black mass material to obtain the first filtrate and the first filter cake; removing contaminants from the first filtrate through de-Cu and de-Al to form second filtrate; producing crude iron phosphate from the second filtrate to form third filtrate, followed by staged precipitation and separation to further remove contaminants from the third filtrate and third filter cake; mixing the precipitate obtained from the staged precipitation step(third filter cake) with the filter cake obtained from the first leaching step (first filter cake); leaching the cake mixture in the presence of a reducing agent to obtainPATENT APPLICATION ATTORNEY DOCKET NO.19054-006WO1 the fourth filtrate; subjecting the fourth filtrate to impurity removal to remove contaminants to form the fifth filtrate; feeding the fifth filtrate to a solvent extraction system to obtain high-purity solutions of Mn, Co, Ni, and Li; and producing battery-grade Mn, Co, and Ni sulfates and lithium carbonate from the solutions, the crude iron phosphate may be purified to battery grade iron phosphate.

[0076] The mixture of batteries may be crushed / shredded, sieved / sorted, and thermally treated in the same system to reduce potential safety hazards. The resulting black mass material may have different elemental compositions, such as Li 0-20%, Ni 0-100%, Co 0- 100%, Mn 0-100%, Al 0-100%, P 0-100%, and Fe 0-100%. The black mass material may be dissolved in the first leaching step in the absence of a reducing agent and an oxidizing agent. The solid to liquid ratio may range from about 1:2 to about 1:10. The final pH after leaching may range from about 0.01 to about 2.0. The acid used may be H2SO4, HCl, HNO3 or H3PO4. The preferred acid used may be H2SO4. The temperature may range from about 20 °C to about 100 °C, and the leaching time may range from 1 minute to 24 hours.

[0077] The impurities may be removed from the first filtrate through de-Cu and de-Al steps. The reaction temperature may range from about 20 °C to about 100 °C. The pH regulator may include but is not limited to NaOH, Na2CO3, KOH, K2CO3, LiOH, Li2CO3 and Fe powder. The Cu may be removed by adding a reducing agent like iron powder and manganese powder with about 10-50% extra theoretical amount. The pH may be controlled in the range of about 0.50 to about 3.0. The Al may be removed by adding a precipitant. The precipitant may include but is not limited to Na2CO3, NaF, KF, LiF, oxalic acid, and diethylenetriaminepentaacetic acid.

[0078] The crude iron phosphate is produced by adding an oxidizing agent. The oxidizing agent may include but is not limited to hydrogen peroxide and ozone. The pH may be controlled in the range of about 0.5 to about 3.0.

[0079] The filtrate after iron phosphate precipitation may be subjected to staged precipitation to further remove contaminants. The pH of the filtrate may be gradually increased to the range of about 4.0 to about 14.0 with the addition of a base, including but not limited to NaOH, Na2CO3, and ammonia.PATENT APPLICATION ATTORNEY DOCKET NO.19054-006WO1

[0080] The filter cake of the first leaching step may be mixed with the filter cake obtained from the staged precipitation step, and the mixture may be dissolved through reductive leaching. The acid used may be H2SO4, HCl, HNO3 or H3PO4. The preferred acid used may be H2SO4. The reducing agent used may be, for example, hydrogen peroxide and SO2, Na2SO3, Na2S2O4. The preferred temperature may be about 30 °C to about 100 ° C. The solid to liquid ratio may range from about 1:2 to about 1:10. The final reaction pH may range from about 0.1 to about 3.0.

[0081] The filtrate obtained from reductive leaching may be subjected to impurity removal to eliminate contaminants. The filtrate after impurity removal may be processed in a solvent extraction system. The system may consist of different operating lines targeting at the purification of different metals, such as Mn solvent extraction line, Co solvent extraction line, and Ni solvent extraction line. The system may contain other operating lines to remove impurities, such Ca solvent extraction line to remove Ca. The different extractants may be used for the purification of different metals. Battery-grade Ni, Co, and Mn sulfates may be produced from the purified solutions by crystallization. Crude Li2CO3 may be produced from the purified solution by carbonate precipitation by adding a carbonate, such as sodium carbonate. Battery-grade Li2CO3 may be produced from crude Li2CO3 by carbonate refinement.

[0082] In another aspect, embodiments described herein may relate to a process based on NMC preferential leaching for the recycling of lithium nickel manganese cobalt oxide (NMC or NCM) batteries or a combination of two or more different types of batteries (i.e., LCO, LMO, NMC, LFP, LNMO, NCA, LMFP, LMP, the process including: discharging, dismantling, crushing / shredding, sieving / sorting, and thermally treating mixed batteries, as well as the scraps generated during lithium-ion battery manufacturing processes, leading to a black mass material that contains anode and cathode materials along with some contaminants; leaching the black mass material in the presence of an oxidizing and a reducing agent, leading to the first filtrate that contains valuable constituents and some contaminants, as well as a filter cake that contains iron phosphate and leaching solid residue; eliminating contaminants from the first filtrate through de-Cu and de-Al to form the second filtrate; subjecting the second filtrate to a solvent extraction system to obtainPATENT APPLICATION ATTORNEY DOCKET NO.19054-006WO1 high-purity separate solutions of Mn, Co, Ni, and Li; producing battery grade Mn, Co, and Ni sulfates and Li carbonate from the solutions; leaching the filter cake of the first leaching step to dissolve iron and phosphorous, leading to a filtrate that contains iron, phosphorous, and some contaminants; removing impurities from the filtrate; and producing crude iron phosphate (FP) from the filtrate, the crude iron phosphate can be purified to battery grade iron phosphate.

[0083] The discharging, dismantling, crushing / shredding, and thermally treatment steps may follow the methods steps of the previous embodiment. Depending on the battery types in the mixture, the resulting black mass material may have different elemental compositions, such as Li 0-20%, Ni 0-100%, Co 0-100%, Mn 0-100%, Al 0-100%, P 0- 100%, and Fe 0-100%. The black mass material may be dissolved under acidic conditions in the presence of a chemical reagent scheme that can oxide FP cathode and reduce NCM cathode. The acid used may be H2SO4, HCl, HNO3 or H3PO4. The chemical reagent scheme may be a combination of an oxidizing agent or a reducing agent. The chemical reagent scheme may be a single chemical showing different redox functions for the different cathode materials. The preferred chemical may be hydrogen peroxide.

[0084] The reaction temperature may range from 20 °C to 100 °C. The solid to liquid ratio may range from 1:2 to 1:10. The de-Cu, de-Al, and solvent extraction steps may follow the method steps of the previous embodiment. The filter cake after redox acid leaching and filtration may be re-leached by dissolving in water in the presence of an acid. The acid used may be H2SO4, HCl, HNO3 or H3PO4. The preferred acid used may be H2SO4. The preferred temperature may be about 20 °C to about 90 ° C. The solid to liquid ratio may range from about 1:2 to about 1:10. The final reaction pH may range from about 0.1 to about 3.0. The impurities may be eliminated from the filtrate using an impurity removal step. The crude iron phosphate may be produced from the filtrate following the method of the previous embodiment.

[0085] Although only a few example embodiments have been described in detail above, those skilled in the art will readily appreciate that many modifications are possible in the example embodiments without materially departing from this invention. Accordingly, all such modifications are intended to be included within the scope of this disclosure asPATENT APPLICATION ATTORNEY DOCKET NO.19054-006WO1 defined in the following claims. In the claims, means-plus-function clauses are intended to cover the structures described herein as performing the recited function and not only structural equivalents, but also equivalent structures.

Claims

PATENT APPLICATION ATTORNEY DOCKET NO.19054-006WO1 CLAIMS What is claimed is:

1. A method for recycling spent or scrap lithium battery materials comprising: selectively redox leaching a black mass comprising lithium battery materials with an acid and a redox agent; selectively removing titanium, copper and aluminum from a first filtrate formed from the redox leaching; and treating a filtrate formed from removing the copper and the aluminum to form battery grade compounds.

2. The method of claim 1, further comprising, before the selectively redox leaching the black mass, selectively acid leaching the black mass with an acid.

3. The method of claim 2, further comprising, after selectively acid leaching: removing titanium from a filtrate formed from acid leaching; removing copper from a filtrate formed from removing the titanium; removing aluminum from a filtrate formed from removing the copper; and precipitating a crude iron phosphate from a filtrate formed from removing the aluminum.

4. The method of claim 3, further comprising, after the precipitating the crude iron phosphate: adjusting a pH of a filtrate formed from precipitating the crude iron phosphate, with a base or precipitant to a range of about 4 to about 10 to remove contaminants; separating a crude lithium carbonate; and precipitating battery grade lithium carbonate from a filtrate formed from separating the crude lithium carbonate.

5. The method of claim 4, wherein the precipitating the battery grade lithium carbonate comprises: iteratively performing mechanical vapor recompression on the filtrate formed from separating the crude lithium carbonate; and precipitating and refining the battery grade lithium carbonate from a concentrated filtrate formed from iteratively performing mechanical vapor recompression.PATENT APPLICATION ATTORNEY DOCKET NO.19054-006WO1 6. The method of claim 4 or 5, further comprising, after the adjusting a pH of a filtrate formed from precipitating the crude iron phosphate, feeding the formed contaminants with a solid formed from acid leaching to the selective redox leaching to form a second filtrate.

7. The method of claim 6, further comprising, after feeding the formed contaminants with the solid formed from acid leaching to selectively redox leaching: removing impurities from the second filtrate formed from the redox leaching; sequentially extracting a filtrate formed from removing the impurities to remove Li, Mn, Co and Ni into respective individual steams; and crystallizing respective individual streams to form their respective battery grade compounds.

8. The method of any one of the above claims, wherein the selectively removing copper from the first filtrate formed from the redox leaching comprises at least one of: treating the first filtrate formed form the redox leaching with a base to adjust a pH of the first filtrate, adding iron powder to the first filtrate formed form the redox leaching, performing selective adsorption or extracting copper with a solvent or combinations thereof; or separating the filtrate formed from removing the copper.

9. The method of any one of the preceding claims, wherein the removing the copper and the aluminum from the first filtrate formed from the redox leaching comprises at least one of: selectively precipitating aluminum by adding a precipitant or complexing agent; or performing selective ion exchange on the filtrate formed from removing the copper.

10. The method of claim 9, wherein the complexing agent is selected from the group consisting of an alkali metal compound, a fluoride compound capable of complexing with aluminum, oxalic acid, diethylenetriaminepentaacetic acid, and combinations thereof.

11. The method of claim 10, wherein the fluoride compound is selected from the group consisting of sodium fluoride, potassium fluoride, sodium fluoride, lithium fluoride, and combinations thereof.PATENT APPLICATION ATTORNEY DOCKET NO.19054-006WO1 12. The method of any one of the preceding claims, wherein the treating the filtrate formed from removing the copper and the aluminum to form battery grade compounds comprises: sequentially extracting the filtrate formed from removing the copper and the aluminum to remove Li, Mn, Co and Ni into respective individual steams; and processing respective individual streams to form respective battery grade compounds.

13. The method of any one of the preceding claims, further comprising, after redox leaching the black mass: acid leaching a solid formed from redox leaching the black mass; removing impurities from a filtrate formed from the acid leaching the solid; oxidizing a filtrate formed from removing impurities from a filtrate formed from the acid leaching the solid; and precipitating iron phosphate from a filtrate formed from oxidizing the filtrate.

14. The method of any one of the preceding claims, wherein the acid for acid leaching and / or redox leaching is selected from inorganic acids, organic acids or mixtures thereof.

15. The method of any one of the preceding claims, wherein the redox agent is selected from the group consisting of hydrogen peroxide, oxygen, ozone, potassium iodide, and combinations thereof.

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