Process for recycling lithium ion batteries

Abstract

The present invention relates to the recycling of used lithium ion batteries and provides a method for processing black mass derived from lithium ion battery materials and comprising iron and manganese.

Description

[0001] BASF SE B25.175P-WO 67056 Ludwigshafen am Rhein 14.01.2026 / lg / np / jl

[0002] Process for recycling lithium ion batteries

[0003] Field of the invention

[0004] The present invention relates to the recycling of used lithium ion batteries and provides a method for processing black mass derived from lithium ion battery materials and comprising iron and manganese.

[0005] Background

[0006] Separate work-up of materials from spent LFP and NMC lithium ion batteries, respectively, has large raw material, space and equipment requirements.

[0007] CN 116706302 A discloses a lithium battery recycling method which comprises the following steps: a pretreatment process: detecting and decomposing lithium battery monomers, then crushing, drying and sorting the lithium battery monomers, then obtaining lithium iron phosphate battery powder and ternary battery powder through pyrolysis, then dosing the lithium iron phosphate battery powder and the ternary battery powder, respectively, into sulfuric acid, and finally, carrying out secondary treatment to obtain lithium iron phosphate battery powder and ternary battery powder; roasting to obtain water-soluble lithium sulfate; a positive electrode material repairing process: carrying out shredding, pyrolysis, screening, iron removal, crushing and electromagnetic iron removal on the waste lithium iron phosphate positive electrode plate and leftover materials, and then mixing and packaging; the acid dissolution impurity removal process comprises lithium iron phosphate battery impurity removal and ternary battery impurity removal, the lithium iron phosphate battery impurity removal is used for removing copper, fluorine and aluminum, and the ternary battery impurity removal is used for removing nickel, cobalt, manganese and copper, aluminum and iron; the extraction process comprises the steps of extracting andremoving impurities and extracting manganese, nickel, cobalt and magnesium; and preparing lithium hydroxide.

[0008] Treatment of mixed LFP and NMC materials such as NMC contaminated with LFP, or batteries utilizing mixed cathode active materials, in one recycling line is complex due to the differences in chemical composition. Freely blending and subsequently working-up battery black masses is not possible without diminishing recovery yields due to value metal phosphate formation and loss of some Ni, Co and Li into the filter cake obtained after precipitation of impurities.

[0009] US 2023 / 0332267 A1 discloses a recycling method for a mixed waste material of lithium nickel manganese cobalt oxide (LNMCO) and lithium iron phosphate (LFP), including: conducting acid-leaching to obtain an acid-leaching liquor with nickel, cobalt, manganese, phosphorus, iron, and lithium; conducting adsorption separation with a resin, washing the resin with sulfuric acid to obtain a mixed solution of nickel sulfate, cobalt sulfate, and manganese sulfate, and subjecting the mixed solution to precipitation to obtain an LNMCO cathode material precursor; and subjecting an obtained solution with phosphorus, iron, and lithium to lithium precipitation to obtain a lithium salt precipitate, and subjecting a post-precipitation solution to concentration and electrospinning to obtain a ferric phosphate / carbon material. The process of the present disclosure can achieve comprehensive recycling of a mixed waste material of LNMCO and LFP and the directed circulation of waste LNMCO and LFP materials.

[0010] CN 115321502 A discloses a comprehensive recovery process of a waste lithium iron phosphate (LFP) battery and a nickel-cobalt-manganese (NMC) ternary battery, which comprises the following steps: 1) respectively crushing the lithium iron phosphate battery and the nickel-cobalt-manganese ternary battery, performing magnetic separation, and sieving to obtain two kinds of battery powder; 2) calcining the two kinds of battery powder separately and mixing them in a mass ratio LFP / NMC of greater than 1:1 to obtain mixed powder; (3) carrying out acid leaching reaction on the mixed powder, adding an oxidizing agent to continuously react after the acid leaching reaction iscompleted, and filtering after the reaction is completed to obtain ferrophosphorus graphite slag and nickel-cobalt-manganese-lithium-containing filtrate; 4) sequentially carrying out extraction treatment, back extraction treatment and secondary extraction treatment, and separating to obtain a nickel-containing precipitate, a lithium-containing solution, a manganese-containing organic phase and a cobalt-containing water phase; and 5) adding the ferrophosphorus graphite slag into a second acid solution for reaction, and filtering to obtain graphite slag and an iron phosphate solution

[0011] CN 114574713 A relates to a method for separating iron, nickel and cobalt from a nickel-cobalt acid leaching solution containing high-concentration iron ions, which comprises the following steps: adding a phosphate radical source and a phosphorus-containing auxiliary agent into a to-be-treated solution containing iron ions, nickel ions and cobalt ions, reacting at the temperature of 10-50°C and the pH value of 1.4-1.9, and then carrying out solid-liquid separation, and a ferric phosphate product and a nickel-cobalt-enriched reaction solution are obtained.

[0012] Summary of the invention

[0013] The present disclosure provides a process for recycling lithium ion batteries, comprising a) providing a mixture of i) 80 to 99 wt.% of black mass derived from lithium ion batteries comprising a cathode active material comprising nickel and / or manganese and / or cobalt and ii) 1 to 20 wt.% of black mass derived from lithium ion batteries comprising a cathode active material comprising iron and phosphate, b) dispersing the mixture in water at a solid to liquid ratio (S / L-ratio) in the range of from 0.1 to 0.5, c) heating the dispersion to a temperature in the range of from 80°C to 95°C, adding sulfuric acid in an amount of from 60 wt.% to 150 wt.%, relative to the solids content of the dispersion, stirring the reaction mixture under non-reactive atmosphere for a period of time in the range of from 1 hour to 4 hours, then introducing air into the reaction mixture at a flow rate in the range of 10 NL / h per kg of reaction mixture to 60 NL / h per kg of reaction mixture while stirring the reaction mixture for a period of time in the range of from 2 hours to 5 hours, then filtering the reaction mixture and removing solids,d) heating the filtrate obtained in step c) to a temperature in the range of from 70°C to 90°C, adjusting the pH of the filtrate to a value in the range of from 3 to 4 by adding a Na2COs solution, and introducing air into the reaction mixture at a flow rate corresponding to 2.5 to 20 mols O2 per mol of Fe per hour, until 20 to 70 mols O2 per mol of Fe in the reaction mixture have been added, then filtering the reaction mixture and removing solids, e) heating the filtrate obtained in step d) to a temperature in the range of from 70°C to 90°C and adjusting the pH of the filtrate to a value in the range of from 4.5 to 5 by adding a Na2COs solution, stirring the reaction mixture for a period of time in the range of from 1 hour to 4 hours, filtering the reaction mixture and removing solids to obtain a filtrate comprising lithium, nickel and / or cobalt and / or manganese.

[0014] Detailed description

[0015] The present disclosure provides a process for recycling lithium ion batteries. The method allows for recovery of value metals such as lithium, nickel and / or cobalt and / or manganese from black mass derived from lithium ion batteries.

[0016] Step a) of the process of the present disclosure involves providing a mixture of i) 80 to 99 wt.%, e.g., 80 to 95 wt.%, for instance, 80 to 90 wt.% of black mass derived from lithium ion batteries comprising a cathode active material comprising nickel and / or manganese and / or cobalt and ii) 1 to 20 wt.%, e.g., 5 to 20 wt.%, for instance, 10 to 20 wt.% of black mass derived from lithium ion batteries comprising a cathode active material comprising iron and phosphate. It has been found that if larger amounts of black mass derived from lithium ion batteries comprising a cathode active material comprising iron and phosphate, e.g., LFP, are present in the mixture, the mass of the filter cake obtained in step d) is increased by an extent resulting in higher value metal losses.

[0017] In the present disclosure, the term “black mass” refers to materials derived from, for example, a lithium ion battery, lithium ion battery waste, lithium ion battery production scrap, lithium ion cell production scrap, lithium ion cathode active material, and / or combinations thereof by mechanical processes such as mechanical comminution. For example, black mass may be derived from batteryscrap by mechanically treating the battery scrap to obtain the active components of the electrodes such as graphite and cathode active material and may include impurities from the casing, electrode foils, cables, separator, and electrolyte. In some examples, the battery scrap may be subjected to a heat treatment to pyrolyze organic (e.g., electrolyte) and polymeric (e.g., separator and binder) materials. Such a heat treatment may be performed before or after mechanical comminution of the battery material.

[0018] Lithium ion batteries can comprise a variety of different cathode active materials, for instance, lithium cobalt oxide (LiCoCh), lithium iron phosphate (LiFePCU or LFP), lithium manganese oxide (LiMn2O4 spinel, or Li2MnO3-based lithium-rich layered materials, LMR-NMC), lithium nickel manganese cobalt oxide (LiNiMnCoCh or NMC) and lithium nickel cobalt aluminum oxides (LiNixCoyAlzO2 with x + y + z = 1 or NCA).

[0019] Lithium ion batteries may be disassembled, after discharging and optionally drying them, punched, milled, for example in a hammer mill, and / or shredded, for example in an industrial shredder. From this kind of mechanical processing the active material of the battery electrodes may be obtained. A light fraction such as housing parts made from organic plastics and aluminum foil or copper foil may be removed, for example, in a forced stream of gas, air separation or classification.

[0020] Battery scraps may stem from, e.g., used batteries or from production waste such as off-spec material. In some embodiments a battery material is obtained from mechanically treated battery scraps, for example from battery scraps treated in a hammer mill or in an industrial shredder. Such material may have an average particle diameter (D50) ranging from 1 pm to 1 cm, such as from 1 pm to 500 pm, for example, from 3 to 250 pm.

[0021] Larger parts of the battery scrap like the housings, the wiring and the electrode carrier films may be separated mechanically such that the correspondingmaterials may be excluded from the battery material that is employed in the process.

[0022] Mechanically treated battery scrap may be subjected to a solvent treatment to dissolve and separate polymeric binders used to bind the transition metal oxides to current collector films, or, e.g., to bind graphite to current collector films. Suitable solvents are N-methylpyrrolidone, N,N-dimethyl-formamide, N,N-dimethylacetamide, N-ethylpyrrolidone, and dimethylsulfoxide, in pure form, as mixtures of at least two of the foregoing, or as a mixture with 1 % to 99 % by weight of water.

[0023] Mechanically treated battery scrap may be subjected to a heat treatment in a wide range of temperatures under different atmospheres. The temperature range is usually in the range of 100°C to 900°C. Lower temperatures below 300°C may serve to evaporate residual solvents from the battery electrolyte, at higher temperatures the binder polymers may decompose while at temperatures above 400°C the composition of the inorganic materials may change as some transition metal oxides may become reduced either by the carbon contained in the scrap material or by introducing reductive gases. In some embodiments, a reduction of lithium metal oxides may be avoided by keeping the temperature below 400°C and / or by removing carbonaceous materials before the heat treatment.

[0024] In some embodiments, the black mass derived from lithium ion batteries comprising a cathode active material comprising nickel and / or manganese and / or cobalt is derived from battery materials comprising LixMO2, wherein x is an integer greater than or equal to one, and M is chosen from metals, transition metals, rare earth metals, and combinations thereof.

[0025] In some embodiments, the black mass derived from lithium ion batteries comprising a cathode active material comprising nickel and / or manganese and / or cobalt is derived from nickel-cobalt-manganese oxide (NCM) battery materials. In other embodiments, the black mass is derived from lithium cobaltoxide (LiCoCh) battery materials. In yet other embodiments, the black mass is derived from lithium manganese oxide (LiMn2O4 spinel, or Li2MnO3-based lithium-rich layered materials, LMR-NMC) battery materials. In still other embodiments, the black mass is derived from lithium nickel cobalt aluminum oxides (LiNixCoyAIzCh with x + y + z = 1 or NCA) battery materials.

[0026] In some embodiments, the battery material comprises lithiated nickel cobalt manganese oxide of formula Lii+x(NiaCobMncM1d)i-xO2, wherein M1 is chosen from Mg, Ca, Ba, Al, Ti, Zr, Zn, Mo, V and Fe, zero < x < 0.2, 0.1 < a < 0.95, zero < b < 0.9 (such as 0.05 < b < 0.5), zero < c < 0.6, zero < d < 0.1 , and a + b + c + d = 1. Exemplary lithiated nickel cobalt manganese oxides include Li(i+x)[Nio.33Coo.33Mno.33](i-x)02, Li(i+x)[Nio.5Coo.2Mno.3](i-x)02, Li(i+x)[Nio.6Coo.2Mno.2](i-x)02, Li(i+X)[Nio.7Coo.2Mno.3](i-x)02, Li(i+x)[Nio.8Coo.iMno.i](i-x)02 each with x as defined above, and Li[Nio.85COo.13Alo.02]02.

[0027] In some embodiments, the battery material comprises lithiated nickel-cobalt aluminum oxides of formula Li[NihCo lj]O2+r, wherein h ranges from 0.8 to 0.90, i ranges from 0.1 to 0.3, j ranges from 0.01 to 0.10, and r ranges from zero to 0.4.

[0028] In some embodiments, the battery material comprises at least one chosen from lithiated cobalt oxide, lithiated manganese oxide, lithiated nickel cobalt manganese oxide, lithiated nickel cobalt aluminum oxide, and combinations thereof.

[0029] In some embodiments, black mass derived from lithium ion batteries comprising a cathode active material comprising iron and phosphate is derived from battery materials comprising lithium metal phosphate of formula LixMPCU, wherein x is an integer greater than or equal to one, and M is chosen from metals, transition metals, rare earth metals, and combinations thereof. Examples include lithium iron phosphate (LiFePCU or LFP) and lithium iron manganese phosphate (LFMP).In step b) of the process of the present disclosure, the mixture of i) i) 80 to 99 wt.%, e.g., 80 to 95 wt.%, for instance, 85 to 95 wt.% of black mass derived from lithium ion batteries comprising a cathode active material comprising nickel and / or manganese and / or cobalt and ii) 1 to 20 wt.%, e.g., 5 to 20 wt.%, for instance, 5 to 15 wt.% of black mass derived from lithium ion batteries comprising a cathode active material comprising iron and phosphate is suspended in DI water with a S / L-ratio in the range of from 0.1 to 0.5, for instance, 0.2 to 0.3, e.g., 0.25.

[0030] In step c) of the process of the present disclosure, the suspension obtained in step b) is heated to a temperature in the range of from 80°C to 95°C, e.g., 90°C, and sulfuric acid is added in an amount of from 60 wt.% to 150 wt.%, e.g., 80 to 130 wt.%, for instance, 95 to 120 wt.%, relative to the solids content, and the reaction mixture is stirred under non-reactive atmosphere for a period of time in the range of from 1 hour to 4 hours. The term "non-reactive atmosphere" means a gas or gas mixture that does not react with the contents of the reaction mixture under the given conditions. Examples of suitable non-reactive atmospheres include water vapor, nitrogen, and noble gases like argon. In one embodiment, water vapor is used as non-reactive atmosphere. Subsequently, air is introduced into the reaction mixture at a flow rate in the range of 10 NL / h per kg of reaction mixture to 60 NL / h per kg of reaction mixture, for instance, 10 NL / h per kg of reaction mixture to 30 NL / h per kg of reaction mixture, e.g., 20 NL / h per kg of reaction mixture, and the reaction mixture is stirred for a further period of time in the range of from 2 hours to 5 hours. The air helps to dissolve any metallic copper or copper salts present in the reaction mixture.

[0031] In some embodiments, the reaction mixture obtained is further leached with sulfuric acid while adding a sulfur-containing reducing agent to the reaction mixture ("reductive leaching"), at a temperature of 70°C to 95°C, for a time of from 1 to 2 h, at a pH of 2.0 or less, e.g., from -1.0 to 2.0, or from 0 to 2.0, or of from 0.5 to 2.0. In an embodiment of the process, up to 2.0 mol / L of the sulfur-containing reducing agent per mol of Ni, Co, Mn present in the reaction mixtureare added. The sulfur-containing reducing agent may be solid, liquid or gaseous. Examples of solid sulfur-containing reducing agents include Na2SO3, and Na2S20s. Examples of liquid sulfur-containing reducing agents include H2SO3. Examples of gaseous sulfur-containing reducing agents include SO2. In some embodiments, the sulfur-containing reducing agent is selected from the group consisting of sulfur dioxide, H2SO3, Na2SO3, and Na2S20s. In some embodiments, the sulfur-containing reducing agent is sulfur dioxide. When sulfur dioxide is injected into the mixture in the reductive leaching step, sulfur dioxide is added to the reaction mixture until it breaks through, i.e., sulfur dioxide can be detected in the rector exhaust. In an embodiment of the process, up to 2.0 mol / L sulfur dioxide per mol of Ni, Co, Mn present in the reaction mixture are added.

[0032] The reaction mixture then is filtered and the solids are removed. The solids remaining after sulfuric acid leach mainly consist of carbon, in particular, graphite.

[0033] In some embodiments of the process, copper ions are removed from the filtrate obtained in step c) between steps c) and d). In some embodiments of the process, the pH of the filtrate obtained in step c) is adjusted to be in the range of from 1.5 to 2.5, and copper ions are subsequently removed from the solution by solvent extraction, followed by solid / liquid separation. Solvent extraction is performed using a solvent comprising a suitable extractant for copper ions. In some embodiments, the copper ions are removed from the solution by extraction with a 1:1 (by volume) mixture of 2-hydroxy-5-nonylacetophenone ketoxime and 5-nonylsalicylaldoxime (LIX 984N). In some embodiments of the process, the copper ions removed from the solution by solvent extraction are subsequently reduced to metallic copper. In some embodiments, the copper ions are reduced by cementation. In other embodiments, the copper ions are reduced by electrolysis (electrowinning).

[0034] In some embodiments of the process, copper ions are removed between steps c) and d) from the filtrate obtained in step c) by precipitation, followed bysolid / liquid separation. In some embodiments, the copper ions are removed from the solution by precipitation of copper sulfide. To precipitate copper sulfide, sulfide, hydrogen sulfide, or thiosulfate ions are added to the filtrate obtained in step c). In some embodiments, Na2S20s is added to the filtrate obtained in step c) to precipitate copper sulfide. The precipitate is separated from the aqueous solution depleted of copper cations by solid / liquid separation, for instance, by filtration.

[0035] In step d) of the process of the present disclosure, the filtrate obtained in step c) is heated to a temperature in the range of from 70°C to 90°C, e.g., 75 °C, and the pH of the filtrate is adjusted to a value in the range of from 3 to 4, e.g., from 3.5 to 4, for instance, 3.8 by adding a Na2COs solution. Air is introduced into the reaction mixture at a flow rate corresponding to 0.5 to 20 mols O2 per mol of Fe per hour, until 2.5 to 70 mols, for instance, from 10 to 50 mols, e.g., from 20 to 30 mols, such as 25.5 mols, O2 per mol of Fe have been added. In some embodiments of the process, the reaction mixture is stirred for a period of time in the range of from 2 hours to 6 hours, e.g., from 3 hours to 4 hours. At the end of step d), the reaction mixture is filtered and the solids are removed.

[0036] During step d) of the process, impurity cations of the group consisting of Al and Fe cations and impurity anions comprising P, F, or Si present in the solution are precipitated from the solution and removed. The presence of iron and phosphate increases the efficiency of aeration during impurity precipitation, i.e. , less air and energy are required in step d). The reaction is faster and less energy is consumed by stirring. The contents of iron and phosphorus, respectively, in the filtrate obtained in step d) are-less than 100 ppm, e.g., less than 50 ppm, or even less than 10 ppm.

[0037] In comparison to a filtrate obtained from a black mass exclusively derived from lithium ion batteries comprising a cathode active material comprising nickel and / or manganese and / or cobalt, the mass of the solids removed in steps c) and d), measured as dry filter cake mass, is increased by less than 50%, e.g., less than 35%, for instance, less than 25%. Quantitative removal of iron andphosphorus from the filtrate can be achieved at lower pH and lower O2:Fe-ratio and with lower energy input by stirring, or at the same pH in shorter aeration time and at lower O2:Fe-ratio.

[0038] In step e) of the process of the present disclosure, the filtrate obtained in step d) is heated to a temperature in the range of from 70°C to 90°C, e.g., 80 °C, and the pH of the filtrate is adjusted to a value in the range of from 4.5 to 5.0, e.g., 4.7, by adding a Na2COs solution. After stirring for a period of time in the range of from 1 hour to 4 hours, e.g., for 120 min to 150 min, the reaction mixture is filtered, and the solids are removed.Examples

[0039] Unless otherwise indicated, all percentages given refer to weight percent.

[0040] "nd" signifies that the corresponding parameter was not determined.

[0041] Feeds

[0042] Table 1 Elemental composition of feed materials as determined by ICP-OES Feed Li Fe Mn P Ni Co

[0043] 1 2.20% 13.70% 1.10% 8.30% 0.52% 0.25% 2 6.5% nd 10.90% nd 34% 11%

[0044] 3 2.10% 13.70% 0.24% 8.80% 0.56% 0.23% 4 7.1% nd 5.7% nd 48.3% 6.1%

[0045] 5 0.72% 0,08% 0.99% 0.08% 2.80% 1.19% 6 3.60% 0.51% 4.50% 1.00% 14.30% 7.50% 7 2.20% 13.70% 1.10% 8.30% 0.05% 0.25% 8 0.61% 0.19% 0.85% 0.15% 2.60% 0.91%

[0046] Example 1 (Comparative)

[0047] 20 g of a LFP BM (Feed 1 ) was suspended in DI water with an S / L-ratio of 0.24. Then 75 wt.-% acid, based on the solids content, was added, and the reaction mixture was stirred for 2 h at 100 °C. The reaction mixture was subsequently filtered, and the solids were washed. 121.7 g Filtrate I and 8.8 g Solids A were obtained.

[0048] Example 2 (Comparative)

[0049] 20 g of a NCM622 CAM (Feed 2) was suspended in DI water with a S / L-ratio of 0.2. Then, a total of 184 wt.-% of acid, based on the solids content, was added over the course of 3 h at 90 °C. The reaction mixture was subsequently filtered and the solids were washed. 153.0 g Filtrate II and 11.0 g Solids B were obtained.

[0050] Example 3 (Comparative)

[0051] 100 g of a LFP BM (Feed 3) and 22.7 g of a NCM811 CAM (Feed 4), corresponding to a molar ratio of LFP:NCM of 1.05:1 was suspended in DI water with a S / L-ratio of 0.25. Then 60 wt.-% acid, based on the solids content,was added and the reaction mixture was stirred for 4 h at 90 °C. The reaction mixture subsequently was filtered and the solids were washed. 327.5 g Filtrate III and 83.1 g Solids C were obtained.

[0052] Table 2 Elemental composition of the filtrates as determined by ICP-OES Filtrate Li Fe P Ni Co Mn

[0053]

[0054] II nd / / 2.2% 0.7% 0.1% III 0.5% 0.7% 0.3% 1.8% 0.2% 0.2%

[0055] Table 3 Elemental composition of the solids as determined by ICP-OES Solid Li Fe P Ni Co Mn

[0056] A 0.1% 0.7% 0.5% nd nd nd

[0057] B nd / / 28.5% 9.7% 17.6% C 0.1% 9.8% 7.2% 0.8% 0.2% 0.1%

[0058] Table 4 Recovery of elements in the filtrate

[0059] Example Li Fe P Ni Co Mn

[0060] 1 98.2% 97.7% 95.3% nd nd nd

[0061] 2 nd / / 53.9% 51.5% 11.2% 3 94.2% 16.0% 11.5% 90.4% 80.4% 93.5%

[0062] Example 4 (Comparative)

[0063] Impurity Precipitation Stage 1

[0064] 558 g of a NCM-based leach solution (Feed 5) was heated to 80 °C and the pH was adjusted to 4 using a Na2CO3-solution. Then aeration was started, and the reaction mixture was stirred with 610 rpm for 250 min. In total, 70 mols O2 per mol of Fe were added. The reaction mixture subsequently was filtered and the solids were washed. 504.9 g Filtrate IV and 43.8 g Solids D were obtained.

[0065] Impurity Precipitation Stage 2

[0066] 429 g of the filtrate obtained first was heated to 80 °C and then the pH was adjusted to 5 using Na2CO3. After stirring with 610 rpm for 120 min, the reactionmixture was filtered, and the solids were washed and dried. 413.5 g Filtrate V and 10.1 g Solids E were obtained.

[0067] Table 5 Elemental composition of the filtrates as determined by ICP-OES Filtrate Li Fe P Ni Co Mn IV 0.52% 0.06% 0.00% 2.43% 0.90% 0.76% V 0.50% 0.05% 0.00% 2.22% 0.87% 0.75%

[0068] Table 6 Elemental composition of the solids as determined by ICP-OES.

[0069] Solid Li Fe P Ni Co Mn D 1.60% 0.26% 0.85% 5.40% nd nd E 1.10% 1.10% 0.05% 17.50% nd nd

[0070] Table 7 Recovery of elements in the filtrate.

[0071] Procedure Li Fe P Ni Co Mn Stage 1 82.6% 63.34% 13.4% 84.9% nd nd Stage 2 98.5% 79.17% / 94.8% nd nd

[0072] Example 5

[0073] Leaching

[0074] 75 g of a 9:1 -mixture of NCM (Feed 6) and LFP (Feed 7) black masses was suspended in DI water with a S / L-ratio of 0.25. The reaction mixture was heated to 90 C, 110 wt.-% acid, based on the solids content, was added and the reaction mixture was stirred for 2 h under inert conditions. Then the atmosphere was exchanged for air, which was introduced at a flow rate of 20 NL / h, and the reaction mixture was stirred for another 5 h. It was subsequently filtered and the solids were washed. 367.6 g Filtrate VI and 15.4 g Solids F were obtained.

[0075] Impurity Precipitation Stage 1

[0076] 300 g of the filtrate obtained was heated to 75 °C and the pH was adjusted to 3.8 using a Na2CO3-solution. Then aeration was started, and the reaction mixture was stirred with 400 rpm for 270 min. In total, 45.5 mols O2 per mol ofFe were added. The reaction mixture was subsequently filtered and the solids were washed. 328.9 g Filtrate VII and 12.0 g Solids G were obtained.

[0077] Impurity Precipitation Stage 2

[0078] 300 g of the filtrate obtained first was heated to 75 °C and then the pH was adjusted to 4.7 using Na2CO3. After stirring with 400 rpm for 160 min, the reaction mixture was filtered, and the solids were washed and dried. 282.8 g Filtrate VIII and 4.5 g Solids H were obtained.

[0079] Table 8 Elemental composition of the filtrates as determined by ICP-OES. Filtrate Li Fe P Ni Co Mn VI 0.57% 0.33% 0.25% 2.30% 1.10% 0.70% VII 0.41% 0.001% < 0.001% 1.60% 0.84% 0.52% VIII 0.37% < 0.001% < 0.001% 1.40% 0.75% 0.47%

[0080] Table 9 Elemental composition of the solids as determined by ICP-OES. Solid Li Fe P Ni Co Mn F 0.17% 0.21% 0.24% 0.77% 0.15% 0.23% G nd 7.80% 5.70% 2.80% 0.92% 0.47% H nd 0.06% 0.03% 6.50% 1.20% 0.30%Table 10 Recovery of elements in the filtrate

[0081] Procedure Li Fe P Ni Co Mn Leach 99.0% 97.6% 97.2% 98.8% 99.5% 98.9% Stage 1 nd 0.33% 8.80% 95.1% 96.7% 97.3% Stage 2 nd / / 93.9% 97.9% 99.1%

[0082] Example 6

[0083] Leaching

[0084] 75 g of a 8:2-mixture of NCM (Feed 6) and LFP (Feed 7) black masses was suspended in DI water with a S / L-ratio of 0.25. The reaction mixture was heated to 90 C, 110 wt.-% acid, based on the solids content, was added and the reaction mixture was stirred for 2 h under inert conditions. Then the atmosphere was exchanged for air, which was introduced at a flow rate of 20 NL / h, and the reaction mixture was stirred for another 5 h. It was subsequently filtered and the solids were washed. 355.9 g Filtrate IX and 13.7 g Solids I were obtained.

[0085] Impurity Precipitation Stage 1

[0086] 300.7 g of the filtrate obtained was heated to 75 °C and the pH was adjusted to 3.8 using a Na2CO3-solution. Then aeration was started, and the reaction mixture was stirred with 400 rpm for 254 min. In total, 25.5 mols O2 per mol of Fe were added. The reaction mixture was subsequently filtered and the solids were washed. 374.6 g Filtrate X and 20.7 g Solids J were obtained.

[0087] Impurity Precipitation Stage 2

[0088] 204.3 g of the filtrate obtained first was heated to 75 °C and then the pH was adjusted to 4.7 using Na2CO3. After stirring with 400 rpm for 126 min, the reaction mixture was filtered, and the solids were washed and dried. 185.3 g Filtrate XI and 2.7 g Solids K were obtained.Table 11 Elemental composition of the filtrates as determined by ICP-OES.

[0089] Filtrate Li Fe P Ni Co Mn

[0090] IX 0.55% 0.55% 0.40% 2.10% 1.00% 0.65% X 0.38% 0.001% < 0.001% 1.40% 0.70% 0.44% XI 0.38% < 0.001% < 0.001% 1.30% 0.70% 0.44%

[0091] Table 12 Elemental composition of the solids as determined by ICP-OES.

[0092] Solid Li Fe P Ni Co Mn

[0093]

[0094] J 0.95% 7.40% 5.00% 3.40% 1.50% 0.93% K 0.38% 0.10% 0.03% 7.90% 1.10% 0.08%

[0095] Table 13 Recovery of elements in the filtrate

[0096] Procedure Li Fe P Ni Co Mn Leach 99.1% 98.4% 98.2% 99.0% 99.6% 98.9% Stage 1 88.1% 0.23% 13.95% 88.9% 89.7% 90.2% Stage 2 98.7% / / 92.5% 97.9% 99.8%

[0097] Example 7

[0098] Impurity Precipitation Stage 1

[0099] 300.6 g of a leach solution from a mixed NCM & LFP black mass (Feed 8) was heated to 75 °C and the pH was adjusted to 3 using a Na2CO3-solution while stirring with 400 rpm. The reaction mixture was stirred for 1 h, whereafter aeration was started, the pH was raised to 4 using Na2CO3, and stirring was continued for another 2 h. In total, 35 mols O2 per mol of Fe were added. The reaction mixture was subsequently filtered and the solids were washed. 293.2 g Filtrate XII and 18.8 g Solids L were obtained.

[0100] Impurity Precipitation Stage 2

[0101] 248.4 g of the filtrate obtained first was heated to 75 °C and then the pH was adjusted to 5 using Na2CO3. After stirring with 400 rpm for 186 min, the reaction mixture was filtered, and the solids were washed and dried. 236.8 g Filtrate XIII and 5.4 g Solids M were obtained.Table 14 Elemental composition of the filtrates as determined by ICP-OES Filtrate Li Fe P Ni Co Mn XII 0.39% < 0.001% < 0.001% 2.50% 0.55% 0.56% XIII 0.40% < 0.001% < 0.001% 1.40% 0.57% 0.57%

[0102] Table 15 Elemental composition of the solids as determined by ICP-OES.

[0103] Solid Li Fe P Ni Co Mn L 1.20% 3.00% 2.30% 4.70% 0.88% 0.66% M 1.10% 0.03% < 0.01% 10.10% 2.20% 1.30%

[0104] Table 16 Recovery of elements in the filtrate.

[0105] Procedure Li Fe P Ni Co Mn Stage 1 87.7% 1.3% 4.1% 88.7% 94.0% 95.1% Stage 2 93.9% / / 91.2% 91.3% 95.0%

Claims

BASF SE B25.175P-WO 67056 Ludwigshafen am Rhein 14.01.2026 / lg / np / jlClaims1. A process for recycling lithium ion batteries, comprisinga) providing a mixture of i) 80 to 99 wt.% of black mass derived from lithium ion batteries comprising a cathode active material comprising nickel and / or manganese and / or cobalt and ii) 1 to 20 wt.% of black mass derived from lithium ion batteries comprising a cathode active material comprising iron and phosphate,b) dispersing the mixture in water at a solid to liquid ratio (S / L- ratio) in the range of from 0.1 to 0.5,c) heating the dispersion to a temperature in the range of from 80°C to 95°C, adding sulfuric acid in an amount of from 60 wt.% to 150 wt.%, relative to the solids content of the dispersion, stirring the reaction mixture under non-reactive atmosphere for a period of time in the range of from 1 hour to 4 hours, then introducing air into the reaction mixture at a flow rate in the range of 10 NL / h per kg of reaction mixture to 60 NL / h per kg of reaction mixture while stirring the reaction mixture for a period of time in the range of from 2 hours to 5 hours, optionally followed by adding a sulfur-containing reducing agent to the reaction mixture and stirring the reaction mixture for a period of time in the range of from 1 hour to 2 hours at a temperature of 70°C to 95°C at a pH of 2.0 or less, then filtering the reaction mixture and removing solids,d) heating the filtrate obtained in step c) to a temperature in the range of from 70°C to 90°C, adjusting the pH of the filtrate to a value in the range of from 3 to 4 by adding a Na2COs solution, and introducing air into the reaction mixture at a flow rate corresponding to 0.5 to 20 mols O2 per mol of Fe per hour, until 2.5 to 70 mols O2 per mol of Fe in the reaction mixture have been added, then filtering the reaction mixture and removing solids,e) heating the filtrate obtained in step d) to a temperature in the range of from 70°C to 90°C and adjusting the pH of the filtrate to a value in the range of from 4.5 to 5.0 by adding a Na2COs solution, stirring the reaction mixture for a period of time in the range of from 1 hour to 4 hours, filtering the reaction mixture and removing solids to obtain a filtrate comprising lithium, nickel and / or cobalt and / or manganese.

2. The process of claim 1 , wherein in step a) a mixture of i) 85 to 95 wt.% of black mass derived from lithium ion batteries comprising a cathode active material comprising nickel and / or manganese and / or cobalt and ii) 5 to 15 wt.% of black mass derived from lithium ion batteries comprising a cathode active material comprising iron and phosphate is provided.

3. The process of claim 1 or 2, wherein in step b) the solid to liquid ratio (S / L- ratio) is in the range of from 0.2 to 0.3.

4. The process of any one of claims 1 to 3, wherein the amount of sulfuric acid added in step c) is in the range of from 95 wt.% to 120 wt.%, relative to the solids content of the dispersion.

5. The process of any one of claims 1 to 4, wherein the pH in step d) is adjusted to a value in the range of from 3.5 to 4.0.

6. The process of any one of claims 1 to 5, wherein in step d) air is introduced into the reaction mixture until 2.5 to 50 mols O2 per mol of Fe have been added.

7. The process of claim 6, wherein in step d) air is introduced into the reaction mixture until 2.5 to 30 mols O2 per mol of Fe have been added.

8. The process of any one of claims 1 to 7, wherein between steps c) and d) the pH of the filtrate obtained in step c) is adjusted to be in the range offrom 1.5 to 2.5, and subsequently copper ions are removed from the filtrate by solvent extraction, followed by solid / liquid separation.

9. The process of any one of claims 1 to 7, wherein between steps c) and d) copper ions are removed from the filtrate by precipitation, followed by solid / liquid separation.

10. The process of claim 9, wherein copper ions are removed from the filtrate by precipitation of copper sulfide.

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