Method for producing particulate (oxy) hydroxides or oxides, particulate (oxy) hydroxides or oxides and use

Abstract

A process for the preparation of a particulate (oxygen) hydroxide or oxide of TM wherein TM represents a metal wherein the process is carried out in a cascade of at least three stirred tank reactors is disclosed.

Description

[0001] The present invention relates to a process for preparing a granular (oxy)hydroxide or oxide of TM, wherein TM stands for a metal, wherein TM comprises nickel and at least one metal selected from the group consisting of cobalt and manganese, and wherein the nickel content of TM is at least 80 mol-%, wherein the process is carried out in a cascade of at least three stirred tank reactors and comprises the following steps:

[0002] (a) providing an aqueous solution (α1) containing Ni and optionally at least one water-soluble salt of a transition metal other than nickel, and an aqueous solution (β1) containing an alkali metal hydroxide, and optionally an aqueous solution (γ1) containing a complexing agent selected from ammonia, glycine, tartrate, citrate and oxalate,

[0003] (b) combining solution (α1) with solution (β1) and, if applicable, solution (γ1) in a first stirred tank reactor at a pH in the range of 11.0 to 13.5, thereby producing slurry of solid particles of the hydroxide of TM,

[0004] (c) transferring the particles from step (b) as a slurry into a second stirred tank reactor,

[0005] (d) providing an aqueous solution (α2) containing Ni and at least one metal selected from Co and Mn and optionally at least one water-soluble salt of a transition metal other than nickel, and an aqueous solution (β2) containing an alkali metal hydroxide and optionally an aqueous solution (γ2) containing a complexing agent selected from ammonia, glycine, tartrate, citrate and oxalate,

[0006] (e) combining solution (α2) with solution (β2) and, if applicable, solution (γ2) in said second stirred tank reactor at a pH in the range of 10.5 to 12.0 and at an average specific energy input in the range of 2 to 8 W / l and lower by a factor of 0.20 to 0.75 than in step (b), thereby growing solid particles of the hydroxide of TM,

[0007] (f) transferring the particles from step (e) as a slurry into a third reactor which is a stirred tank reactor,

[0008] (g) combining solution (α2) with solution (β2) and, if applicable, solution (γ2) in said third stirred tank reactor at a pH value in the range of 10.5 to 12.0,

[0009] wherein the average specific energy input in step (g) is in the range of 0.5 to 2 W / l and is lower by a factor of 0.20 to 0.75 than in step (e), and wherein the pH values are determined at 23°C.

[0010] Lithiated transition metal oxides are currently used as electrode active materials for lithium-ion batteries. Over the past few years, extensive research and development efforts have been conducted to improve properties such as charge density, specific energy, and other properties that may adversely affect the lifespan or applicability of lithium-ion batteries (such as reduced cycle life and capacity loss). Additional efforts have been made to improve manufacturing methods.

[0011] In a typical method for making cathode materials for lithium-ion batteries, a so-called precursor is first formed by coprecipitating a transition metal, preferably into a hydroxide (e.g., oxyhydroxide), which may or may not be alkaline. The hydroxides may be pre-calcined and converted into oxides or oxyhydroxides, or they may be mixed directly with a lithium source (such as, but not limited to, LiOH, Li2O, Li2O2, or Li2CO3) and calcined (fired) at high temperature. The lithium source may be used as one or more hydrates or in a dehydrated form. Calcination (or firing) - also often referred to as thermal treatment or heat treatment of the precursor - is typically carried out at a temperature in the range of 600°C to 1000°C. During the thermal treatment, a solid-state reaction occurs and an electrode active material is formed. The thermal treatment is carried out in the heating zone of an oven or kiln.

[0012] A typical class of cathode active materials that provide high energy density contains a large amount of Ni (Ni-rich), for example, at least 80 mol-% relative to the non-lithium metal. However, energy density still needs to be improved.

[0013] To a large extent, the properties of the precursor are converted into the properties of the corresponding electrode active material, such as particle size distribution, content of the corresponding transition metal, etc. Therefore, the properties of the electrode active material can be influenced by controlling the properties of the precursor.

[0014] It has been found desirable to prepare precursors having a narrow particle size distribution, see for example EP 2 720 305 A. Furthermore, it is desirable to provide precursors having a high sphericity.

[0015] In CN 112591807 A, a multi-stage co-precipitation method for producing high-density precursors is disclosed.

[0016] An object of the present invention is to provide a process by which a precursor for a cathode active material having high porosity, a narrow particle size distribution, a low tendency to form agglomerates and a high reactor efficiency can be prepared. A further object is to provide a precursor for a cathode active material having a narrow particle size distribution and a low tendency to form agglomerates.

[0017] It has been found that by avoiding particle agglomeration during the start-up of the seeded batch growth phase, a precursor that serves as a starting material for cathode active materials with a high volumetric energy density can be obtained. Without wishing to be bound by any theory, we hypothesize that high solids content helps to efficiently avoid unwanted agglomeration. Conventional two-stage processes do not allow starting with a sufficiently high solids content because, in this case, the final batch solids content would be undesirably high.

[0018] Accordingly, the method stated at the beginning (hereinafter also referred to as the method of the present invention) was found. The method of the present invention is a method for preparing a granular oxyhydroxide or oxide of TM. The granular oxyhydroxide or oxide then serves as a precursor for an electrode active material, and therefore it can also be referred to as a precursor. The method of the present invention comprises the following steps (a) and (b) and (c) and (d) and (e) and (f) and (g), hereinafter also referred to as step (a) and step (b) and step (c) and step (d) and step (e) and step (f) and step (g), respectively, or simply referred to as (a) or (b) or (c) or (d) or (e) or (f) or (g). The method of the present invention will be described in more detail below.

[0019] The resulting TM (oxy)hydroxide or oxide is in particulate form. The particle size distribution can be determined by light scattering, laser diffraction, or electroacoustic spectroscopy, with laser diffraction being preferred. The particle size distribution can be characterized by a scan plot of (D90 – D10) divided by D50, where D50 is the median value. Preferably, the resulting (oxy)hydroxide has a span of less than 0.3, more preferably between 0.10 and 0.28, and even more preferably between 0.15 and 0.25.

[0020] In one embodiment of the present invention, the particle shape of the secondary particles of the obtained precursor is spheroids, i.e., particles having a spherical shape. Spheroids should include not only those particles that are completely spherical, but also those particles in which at least 90% (number average) of a representative sample have a maximum and minimum diameter that differ by no more than 10%.

[0021] In one embodiment of the present invention, the resulting precursor consists of secondary particles that are agglomerates of primary particles.

[0022] In one embodiment of the present invention, the specific surface area (BET) of the obtained precursor is, for example, determined by nitrogen adsorption according to DIN-ISO 9277:2003-05 in the range of 2 to 120 m 2 / g range.

[0023] The precursor is an (oxy)hydroxide of TM, wherein TM comprises Ni, and optionally at least one transition metal selected from Co and Mn, and optionally at least one additional metal selected from Ti, Zr, Mo, W, Al, Mg, Nb, Sb and Ta. Preferably, the precursor comprises nickel and at least one metal selected from Co and Mn, more preferably, the precursor comprises nickel, cobalt and manganese.

[0024] The oxide of TM may contain, for example, residual hydroxyl or carbonate groups in the range of 100 to 1,000 ppm (by mass) as determined by differential thermogravimetry ("DSC") as weight loss at temperatures in the range of 180°C to 450°C.

[0025] In one embodiment of the present invention, TM is a combination of metals according to formula (I)

[0026] (Ni a Co b Mn c ) 1-d M d (I)

[0027] in

[0028] a is in the range of 0.80 to 0.97, preferably 0.83 to 0.95,

[0029] b is zero or in the range of 0.025 to 0.2, preferably 0.025 to 0.15,

[0030] c is in the range of zero to 0.2, preferably zero to 0.15, or 0.01 to 0.15, and

[0031] d is in the range of zero to 0.1, preferably zero to 0.05,

[0032] M is selected from the group consisting of Ti, Zr, Mo, W, Al, Mg, Nb, Sb and Ta,

[0033] a+b+c=1.

[0034] Preferably, d=zero.

[0035] TM may contain trace amounts of additional metal ions as impurities, for example trace amounts of ubiquitous metals such as sodium, calcium or zinc, but such trace amounts will not be considered in the description of the present invention. Trace amounts in this context will mean amounts of 0.05 mol-% or less relative to the total metal content of the TM.

[0036] Step (a) comprises providing an aqueous solution (α1) containing Ni, and optionally at least one metal selected from Co and Mn, and optionally at least one other metal selected from Ti, Zr, Mo, W, Al, Mg, Nb, Sb and Ta, and an aqueous solution (β1) containing an alkali metal hydroxide and optionally an aqueous solution (γ1) containing a complexing agent selected from ammonia, glycine, tartrate, citrate and oxalate.

[0037] The term "water-soluble salt" refers to a salt that exhibits a solubility of 25 g / l or more in distilled water at 25°C, the amount of salt being determined ignoring water of crystallization and water from aquo complexes. The water-soluble salts of nickel, cobalt and manganese may preferably be Ni 2+ and Co 2+ and Mn 2+ Examples of water-soluble salts of nickel, cobalt and manganese are sulfates, nitrates, acetates and halides (especially chlorides). Nitrates and sulfates are preferred, with sulfates being more preferred.

[0038] Said aqueous solution (α1) preferably contains Ni and one or more further metals in relative concentrations of the TM intended as a precursor or one of the parts of the precursor. Preferably, the solution (α1) contains nickel and salts of cobalt and manganese.

[0039] The aqueous solution (α1) preferably contains Ni and optionally one or more further metals in a total concentration of 0.5 to 2.2 mol / l.

[0040] The solution (α1) may have a pH value in the range of 2 to 5. In embodiments where a higher pH value is desired, ammonia may be added to the solution (α1). In other embodiments, no ammonia is added to the solution (α1).

[0041] Furthermore, an aqueous solution of an alkali metal hydroxide is provided in step (a), hereinafter also referred to as solution (β1). Examples of alkali metal hydroxides are cesium hydroxide, preferably potassium hydroxide and a combination of sodium hydroxide and potassium hydroxide, and even more preferably sodium hydroxide.

[0042] In embodiments where the solution (β1) contains an alkali metal hydroxide, the solution (β1) may additionally contain an amount (e.g., 0.1% to 2% by weight relative to the corresponding amount of alkali metal hydroxide) of carbonate added intentionally or by aging the solution or the corresponding alkali metal hydroxide.

[0043] The solution (β1) may have an alkali metal hydroxide concentration in the range of 0.1 to 12 mol / l, preferably 6 to 10 mol / l.

[0044] The pH value of the solution (β1) is preferably 13 or higher, for example 14.5. In the context of the present invention, pH values are measured at 23° C. unless expressly stated otherwise.

[0045] In the process of the present invention, ammonia is preferably used. Solution (γ1) - if applicable - contains a complexing agent selected from ammonia, glycine, tartrate, citrate and oxalate. In the context of the present invention, the term glycine includes the compound glycine and its alkali metal salts, such as potassium salt or preferably sodium salt. The terms tartrate and oxalate include the corresponding free acids as well as monoalkali metal salts and dialkali metal salts, such as monopotassium salt or dipotassium salt or monosodium salt or disodium salt or mixed sodium and potassium salts. The term "citrate" includes citric acid and its alkali metal salts, such as monosodium salt or disodium salt or trisodium salt as well as monopotassium salt, dipotassium salt and tripotassium salt.

[0046] In one embodiment of the present invention, the solution (γ1) has an ammonia concentration in the range of 1 to 30% by weight.

[0047] In one embodiment of the present invention, the solution (γ1) contains a complexing agent in the range of 0.05 to 1.0 mol% relative to TM, the complexing agent being selected from glycine, tartrate, citrate and oxalate, or the corresponding alkali metal salts thereof.

[0048] Step (b) comprises combining solution (α1) with solution (β1) and, if applicable, solution (γ1) at a pH in the range of 11.0 to 13.5, preferably 11.2 to 12.5, thereby producing particles of the hydroxide of TM. The particles are slurried in an aqueous medium. Again, unless expressly stated otherwise, pH values are measured at 23°C.

[0049] In one embodiment of the present invention, step (b) is carried out at a temperature in the range of 10°C to 85°C, preferably in the range of 40°C to 65°C.

[0050] In one embodiment of the present invention, step (b) is carried out at a pressure in the range of 500 mbar to 10 bar, preferably at ambient pressure.

[0051] In one embodiment of the invention, an average specific energy of 8 to 20 W / l, preferably 9 to 17 W / l, is introduced into the slurry, for example, by a pitch-blade turbine, preferably a Rushton turbine, or a combination of a pitch-blade turbine and a Rushton turbine. The agitator may be one-stage, two-stage, or multi-stage (e.g., three-stage or four-stage), with two-stage and three-stage being preferred.

[0052] The energy introduction can be kept constant or varied during step (b).

[0053] In one embodiment of the present invention, step (b) is carried out in a continuous stirred tank reactor ("CSTR"). A CSTR is typically equipped with an overflow pipe. In step (b), a slurry of particles having an average diameter (D50) in the range of 3 to 5 μm is preferably removed and fed to a second stirred tank reactor. It is preferred to carry out step (b) in a batch reactor.

[0054] In one embodiment of the invention, the solids content of the slurry removed from step (b) is in the range of 100 to 800 g / l.The solids content is determined by dissolving the precipitate in sulfuric acid and measuring the metal content by IC (Inductively Coupled Plasma).

[0055] In one embodiment of the present invention, step (b) is carried out in a continuous stirred tank reactor operated with an average residence time of 5 to 15 hours, preferably 7 to 12 hours. In the embodiment in which step (b) is carried out in a batch reactor, an average residence time of 15 to 60 hours is preferred. In the embodiment in which step (b) is carried out in a batch reactor, an average residence time of 15 to 60 hours is preferred. In the embodiment in which step (b) is carried out in a batch reactor, an average residence time of 15 to 60 hours is preferred. In the embodiment of step (b), the flow rate is different due to, for example, different feed rates of solution (α2) and solution (β2) and, if applicable, solution (γ2), and the provisional residence time can be calculated. Typically, in the embodiment in which the flow rate of at least one of solution (α2) and solution (β2) and, if applicable, solution (γ2) varies greatly, the average residence time corresponds neither to the maximum residence time nor to the minimum residence time.

[0056] In step (c), the particles from step (b) are transferred as a slurry to a second stirred tank reactor. This second stirred tank reactor is preferably operated as a batch reactor. In order to handle the continuous supply of slurry from step (b), it is preferred to have two or more tank reactors for step (e) that can be operated in parallel.

[0057] Step (d) comprises providing an aqueous solution (α2) containing a water-soluble salt of Ni and at least one transition metal selected from Co and Mn and optionally at least one additional metal selected from Ti, Zr, Mo, W, Al, Mg, Nb, Sb and Ta and an aqueous solution (β2) containing an alkali metal hydroxide and optionally an aqueous solution (γ2) containing ammonia.

[0058] In the context of the present invention, the term "metal-containing solution" shall mean that such solution contains a salt of said metal.

[0059] The aqueous solution (α2) preferably contains Ni and one or more further metals in relative concentrations intended to be the TM of the precursor or one of the parts of the precursor.

[0060] The solution (α2) may have the same composition as that of the solution (α1) or a different composition.

[0061] The aqueous solution (α2) preferably contains Ni and optionally one or more further metals in a total concentration of 0.1 to 12 mol / l, preferably 6 to 10 mol / l.

[0062] The solution (α2) may have a pH value in the range of 2 to 5. In embodiments where a higher pH value is desired, ammonia may be added to the solution (α2).

[0063] The aqueous solution (α2) preferably contains Ni and optionally one or more further metals in a total concentration of 0.5 to 2.2 mol / l.

[0064] In addition, an aqueous solution of alkali metal hydroxide is also provided in step (a), hereinafter also referred to as solution (β2). Solution (β2) can have an alkali metal hydroxide concentration in the range of 0.1 to 12 mol / l, preferably 6 to 10 mol / l.

[0065] The pH value of the solution (β2) is preferably 13 or higher, for example 14.5.

[0066] In the process of the present invention, ammonia can be used, but it can be fed separately as solution (γ2) or in solution (β2) or in solution (α2).

[0067] The solution (β2) may have the same composition as or a different composition from that of the solution (β1), but preferably the same composition.

[0068] The solution (γ2) may have the same composition as or a different composition from that of the solution (γ1), but preferably the same composition.

[0069] In one embodiment of the present invention, the solution (γ2) has an ammonia concentration in the range of 1 to 30% by weight.

[0070] In one embodiment of the present invention, the solution (γ2) contains a complexing agent in the range of 0.05 to 1.0 mol% relative to TM, the complexing agent being selected from glycine, tartrate, citrate and oxalate, or the corresponding alkali metal salts thereof.

[0071] Step (e) comprises combining solution (α2) and solution (β2) and, if applicable, solution (γ2) at a pH in the range of 10.5 to 12.0, preferably at a pH lower than in step (b) (e.g., at least 0.5 units lower), preferably at a pH in the range of 11 to 12.5, thereby growing particles of the hydroxide of TM. The particles are slurried in an aqueous medium.

[0072] In one embodiment of the present invention, step (e) is performed at a temperature in the range of 10 to 85° C., preferably 40 to 65° C. Steps (b) and (e) may be performed at different temperatures or preferably at the same temperature.

[0073] In one embodiment of the present invention, step (e) is carried out at a pressure in the range of 500 mbar to 10 bar, preferably at ambient pressure.

[0074] In step (e), an average specific energy input of 2 to 8 W / l, preferably 2 to 7 W / l, is introduced into the slurry in step (e), for example by means of a stirrer as used in step (b), and the energy input is lower by a factor of 0.20 to 0.75 than in step (b). The average specific energy input can be constant or variable over the time of step (e). In the case where the average specific energy input is not constant, the above values refer to average values.

[0075] In one embodiment of the present invention, the average particle size of the (oxy)hydroxide prepared in step (e) is in the range of 6.5 to 9.5 μm, but in any case is larger than the average particle size at the end of step (b) and in step (c).

[0076] In one embodiment of the present invention, the solid content at the start of step (e) is in the range of 20 to 60 g / l. If the slurry obtained from step (b) and in step (c) has a higher concentration and thus has a higher solid content, step (e) first dilutes the slurry with an aqueous medium (such as water), for example by charging the corresponding tank reactor with an aqueous medium (such as water, diluted ammonia, etc.).

[0077] In one embodiment of the present invention, the solids content at the end of step (e) is in the range of 200 to 800 g / l.

[0078] In one embodiment of the present invention, step (e) has a duration in the range of 7 to 45 hours, preferably 15 to 40 hours, but in any case shorter than step (b).

[0079] The feed rates of the solutions (α2), (β2) and (γ2) in step (e) can be constant or variable, they can for example increase or decrease or swing. When the feed rate is constant, the average residence time is the same as the residence time.

[0080] In the embodiment of step (e), the flow rates are different due to, for example, different feed rates of solution (α2) and solution (β2), and if applicable, solution (γ2), resulting in different flow rates, and a temporary residence time can be calculated. In general, in embodiments in which the flow rates of at least one of solution (α2) and solution (β2) and, if applicable, solution (γ2) vary greatly, the average residence time corresponds to neither the maximum residence time nor the minimum residence time.

[0081] Step (f) comprises transferring the particles from step (e) as a slurry into a third reactor, which is a stirred tank reactor, preferably a batch reactor, such as a draft tube reactor. Draft tube reactors are known per se, for example, from T. Kumaresan et al., Hydrometallurgy, 2014, 150, p. 107 et seq.

[0082] Step (g) comprises combining solution (α2) with solution (β2) and, if applicable, solution (γ2) in the third stirred tank reactor at a pH in the range of 10.5 to 12.0, wherein the average specific energy input in step (g) is lower than that in step (e). Solutions (α2), (β2) and (γ2) in step (g) may have the same composition as in step (e) or a different composition, preferably, they have the same composition.

[0083] At the start of step (g), the solids content in the third stirred tank reactor is relatively low, for example, 60 to 180 g / l. If the slurry obtained from step (e) has a higher concentration and thus a higher solids content, step (g) first dilutes the slurry with an aqueous medium (such as water), for example by charging the corresponding tank reactor with an aqueous medium (such as water, diluted ammonia, etc.).

[0084] At the end of step (g), the solids content is relatively high, for example between 200 and 800 g / l.

[0085] In one embodiment of the invention, an average specific energy input of 0.2 to 2 W / l, preferably 0.2 to 1.9 W / l, which is lower by a factor of 0.20 to 0.75 than in step (e), is introduced into the slurry in step (g), for example, by means of a pitch turbine, a propeller stirrer or hydrofoils. The specific energy input may be constant or variable over the time of step (g). In the case where the specific energy input is not constant, the above values refer to average values.

[0086] In one embodiment of the present invention, step (g) is performed at a temperature in the range of 10° C. to 85° C., preferably 40° C. to 65° C. Steps (g) and (e) may be performed at different temperatures or preferably at the same temperature.

[0087] In one embodiment of the present invention, step (g) is carried out at a pressure in the range of 500 mbar to 10 bar, preferably at ambient pressure.

[0088] In one embodiment of the present invention, step (g) has a duration in the range of 2 to 7 hours, but in any case shorter than step (e).

[0089] The feed rate or feed rates of the solutions (α2), (β2) and (γ2) in step (g) may be constant or variable, they may for example increase or decrease or swing. In the case where the feed rate is constant, the average residence time is the same as the residence time.

[0090] In one embodiment of the present invention, the tank reactors in steps (b), (e) and (g) have different volumes. In another embodiment, the size and volume of the tank reactors in steps (b), (e) and (g) are the same.

[0091] In one embodiment of the present invention, step (g) is performed in a draft tube reactor. The draft tube is comparable to a tube within the vessel body of a tank reactor, wherein the upper edge or at least one opening of the tube is lower than the thickness (gauge) of the slurry in the tank reactor. Thus, the slurry circulates through the draft tube. The agitator element is then positioned within the draft tube.

[0092] In one embodiment of the present invention, in steps (b), (e), and (g), the mother liquor is withdrawn from the reactor, for example, through a clarifier (e.g., a laminar clarifier, a candle filter, or a thickener). The mother liquor may contain, for example, 2 mg / l to 20 g / l of solid particles of the precursor, or may be free of solid particles to the naked eye.

[0093] In one embodiment of the present invention, the slurries from steps (b) and (e) are transferred to a buffer vessel before they are subjected to the next co-precipitation step.

[0094] In one embodiment of the present invention, the average particle size of the (oxy)hydroxide prepared in step (g) is in the range of 9.5 to 18 μm, but in any case is larger than the average particle size at the end of step (e).

[0095] In one embodiment of the present invention, the method of the present invention comprises an additional step (h): separation of the particulate oxy(hydr)oxide by a solid-liquid separation method and subsequent drying.

[0096] By carrying out the method of the present invention, an aqueous slurry is formed. From the aqueous slurry, a particulate mixed hydroxide can be obtained by performing one or more solid-liquid separation steps (e.g., filtration or centrifugation). Additional post-treatment measures may be taken, such as washing with water or ammonia or NaOH solution, dehydration, drying under inert gas or air, etc. If dried under air, partial oxidation may occur and a mixed oxyhydroxide of TM is obtained. Drying can be carried out at a temperature in the range of 100°C to 150°C.

[0097] In one embodiment of the present invention, the method of the present invention comprises a heating step (i) at a temperature in the range of 400°C to 550°C in the absence of a lithium compound. By step (i), the precursor is converted into an oxide of TM. Step (i) can be carried out in a rotary kiln, in a fluidized bed, or in a roller hearth kiln.

[0098] In one embodiment of the present invention, step (i) is performed under an atmosphere of air, oxygen-enriched air, or pure oxygen.

[0099] In one embodiment of the present invention, step (i) has a duration in the range of 1 hour to 12 hours.

[0100] The precursors obtained according to the process of the present invention are excellent starting materials for cathode active materials suitable for producing batteries with high volumetric energy density. The volumetric density depends on the compaction density and the discharge capacity of a given cathode active material.

[0101] Another aspect of the present invention relates to a precursor, hereinafter also referred to as the precursor of the present invention. In one embodiment of the present invention, the precursor of the present invention is a granular (oxy)hydroxide of TM having a particle size distribution (D90-D10) / D50 span of less than 0.30, wherein the TM comprises nickel and at least one metal selected from cobalt and manganese, and wherein the secondary particles of the precursor of the present invention are composed of primary particles. These secondary particles have a core and a shell and concentric porous layers, the concentric porous layers having a density higher than the density of the core and the shell. The concentric layers are visible from scanning electron microscopy (SEM) photographs. The average pore volume of the precursor of the present invention, which is the (oxy)hydroxide, is determined by nitrogen adsorption in the range of 0.033 to 0.1 ml / g. Preferably, the thickness of the intermediate layer may be in the range of 0.5 to 6.0 μm and the diameter of the core in the range of 2.0 to 6.0 μm.

[0102] Another embodiment of the precursor of the present invention is a particulate oxide of TM having a particle size distribution (D90-D10) / D50 span of less than 0.30, for example, from 0.20 to 0.29, wherein the TM comprises nickel and at least one metal selected from cobalt and manganese, and wherein the particles consist of primary particles, and an average pore volume determined by nitrogen adsorption in the range of 0.1 to 0.5 ml / g, preferably 0.12 to 0.3 ml / g.

[0103] The span in each case refers to a secondary particle.The secondary particles are formed by agglomeration of essentially radially oriented primary particles.

[0104] The span of the precursors of the present invention is below 0.30, for example in the range of 0.10 to 0.28, preferably 0.18 to 0.26. The percentiles and medians of D10, D90 are preferably determined by light scattering or laser diffraction or electroacoustic spectroscopy, laser diffraction being preferred.

[0105] TM is as defined above in General.

[0106] The granular (oxy)hydroxide of the TM of the present invention has a total pore / intrusion volume in the range of 0.033 to 0.1 ml / g, preferably 0.035 to 0.07 ml / g, with a pore size range of 20 to This is determined by N2 adsorption according to DIN 66134 (1998) when sample preparation for N2 adsorption measurement is done by degassing at 120°C for 60 minutes.

[0107] In a preferred embodiment, the average pore size of the particulate transition metal (oxy) hydroxide of the present invention is 50 to 100 nm as measured by N adsorption. within the range.

[0108] In one embodiment of the present invention, the particulate transition metal (oxy)hydroxide of the present invention has an average secondary particle size D50 in the range of 2 to 20 μm, preferably 2 to 16 μm and even more preferably 10 to 16 μm.

[0109] In one embodiment of the present invention, TM is a combination of metals according to formula (I)

[0110] (Ni a Co b Mn c ) 1-d M d (I)

[0111] in

[0112] a is in the range of 0.80 to 0.97, preferably 0.83 to 0.95,

[0113] b is zero or in the range of 0.025 to 0.2, preferably 0.025 to 0.15,

[0114] c is in the range of zero to 0.2, preferably zero to 0.15, or 0.01 to 0.15, and

[0115] d is in the range of zero to 0.1, preferably zero to 0.05,

[0116] M is selected from the group consisting of Ti, Zr, Mo, W, Al, Mg, Nb, Sb and Ta,

[0117] a+b+c=1.

[0118] TM may contain trace amounts of additional metal ions as impurities, for example trace amounts of ubiquitous metals such as sodium, calcium or zinc, but such trace amounts will not be considered in the description of the present invention. Trace amounts in this context will mean amounts of 0.05 mol-% or less relative to the total metal content of the TM.

[0119] The precursors of the present invention may contain some carbonates. Carbonates may be incorporated unintentionally, for example from carbonates of alkali metal hydroxides or by absorbing CO2 when exposed to air. The precursors of the present invention may also contain some counterions from water-soluble salts that have served as a source of, for example, nickel during the precursor manufacturing process. Such counterions are preferably sulfates. The amount of impurities such as carbonates and counterions from sources of nickel and one or more additional metals preferably does not exceed 1% by weight of the precursors of the present invention.

[0120] In one embodiment of the present invention, the precursor of the present invention has a range of 2 to 120 m 2 / g, preferably 4 to 50m 2 The specific surface area according to BET (hereinafter also referred to as “BET surface area”) is in the range of 1000 Å / g. The BET surface area can be determined according to DIN ISO 9277:2010 by nitrogen adsorption after degassing the sample at 200° C. for 30 minutes or more.

[0121] As previously outlined, the secondary particles are formed by agglomeration of substantially radially oriented primary particles.

[0122] Furthermore, at least 60% of the volume of the secondary particles is filled with radially oriented primary particles. Preferably, only a minor inner portion of the volume of those particles, e.g. at most 40%, preferably at most 20%, is filled with non-radially oriented primary particles, e.g. randomly oriented primary particles.

[0123] The oxide precursor of the present invention has a viscosity of 0.1 to 0.5 ml / g, preferably 0.12 to 0.3 ml / cm 3Total pore / intrusion volume in the range of 20 to This is determined by N2 adsorption according to DIN 66134 (1998) when sample preparation for N2 adsorption measurement is done by degassing at 120°C for 60 minutes.

[0124] In a preferred embodiment, the average pore size of the oxide precursor of the present invention is 30 to 100 nm as measured by N adsorption. Preferably 50 to within the range.

[0125] In one embodiment of the present invention, the precursor of the present invention has an average secondary particle size D50 in the range of 2 to 20 μm, preferably 2 to 16 μm and even more preferably 10 to 16 μm.

[0126] In one embodiment of the present invention, in the (oxy)hydroxide of the TM of the present invention

[0127] - at least 60 vol.% of the secondary particles consist of primary particles which are radially oriented or which show a maximum deviation from a completely radial orientation of 11 degrees, and

[0128] - wherein the particle precursor has a total pore / intrusion volume in the range of 0.033 to 0.1 ml / g as determined by N2 adsorption.

[0129] In one embodiment of the present invention, in the oxide of the TM of the present invention

[0130] - at least 60 vol.% of the secondary particles consist of primary particles which are radially oriented or which show a maximum deviation from a completely radial orientation of 11 degrees, and

[0131] - wherein the particulate oxide of the TM has a total pore / intrusion volume in the range of 0.1 to 0.5 ml / g as determined by N2 adsorption.

[0132] The precursors of the present invention have an excellent spherical shape. They are almost completely spherical, with an average shape factor of 0.98 or greater.

[0133] The (average) shape factor is determined as follows:

[0134] The shape factor of individual particles was calculated from the perimeter and area measured from the top-view SEM images:

[0135] Shape factor = (4π·area) / (perimeter) 2

[0136] While a perfect sphere would have a shape factor of 1.0, any deviation from perfect sphericity results in a shape factor < 1.0.

[0137] To determine the average shape factor, the shape factors of at least 50 individual particles of a representative sample are first determined and then averaged. This is why it can also be called the average shape factor.

[0138] In one embodiment of the present invention, the precursor of the present invention has a relative humidity of 2 to 120 m / s measured according to DIN after heating to 120°C. 2 The specific surface area according to BET is in the range of 1.5-2.5 μg / g.

[0139] The precursors obtained according to the method of the present invention are excellent starting materials for cathode active materials suitable for producing batteries with high volumetric energy density and excellent cycling stability. Such cathode active materials are prepared by mixing with a lithium source (e.g., Li2O or LiOH or Li2CO3, each free of water or as a hydrate) and calcining (e.g., at a temperature in the range of 600°C to 1000°C). A further aspect of the present invention is therefore the use of the precursor of the present invention for producing a cathode active material for a lithium ion battery, and another aspect of the present invention is a method for producing a cathode active material for a lithium ion battery - hereinafter also referred to as the calcination of the present invention - wherein the method comprises the steps of mixing the precursor of the present invention with a lithium source and heat-treating the mixture at a temperature in the range of 600°C to 1000°C. Preferably, the ratio of the precursor of the present invention to the lithium source in such a method is selected so that the molar ratio of Li to TM is in the range of 0.95:1 to 1.2:1.

[0140] The precursors yield cathode active materials with very good volumetric energy density. Without wishing to be bound by any theory, it can be assumed that the orientation and high sphericity of the primary crystals lead to such favorable properties.

[0141] Examples of calcination of the present invention include heat treatment at a temperature in the range of 600° C. to 900° C., preferably 650° C. to 850° C. The terms “heat treatment” and “heat treatment” are used interchangeably in the context of the present invention.

[0142] In one embodiment of the present invention, the mixture obtained by calcining the present invention is heated to 600° C. to 900° C. at a heating rate of 0.1 to 10° C. / min.

[0143] In one embodiment of the present invention, the temperature is increased and then reaches the desired temperature of 600° C. to 900° C., preferably 650° C. to 800° C. For example, the mixture obtained from step (d) is first heated to a temperature of 350° C. to 550° C., and then kept constant for a period of 10 min to 4 hours, and then it is increased to 650° C. up to 800° C., and then kept at 650° C. to 800° C. for 10 minutes to 10 hours.

[0144] In one embodiment of the present invention, the calcination is carried out in a roller-hearth kiln, a pusher kiln, a rotary kiln, or a combination of at least two of these. The advantage of a rotary kiln is that the homogeneity of the material produced is very good. In roller-hearth and pusher kilns, different reaction conditions for the different steps can be easily set. For laboratory-scale experiments, box and tube furnaces, as well as split-tube furnaces, are also feasible.

[0145] In one embodiment of the present invention, the calcination of the present invention is carried out in an oxygen-containing atmosphere, for example, in a nitrogen-air mixture, a noble gas-oxygen mixture, air, oxygen or oxygen-enriched air. In a preferred embodiment, the atmosphere in step (d) is selected from air, oxygen and oxygen-enriched air. The oxygen-enriched air can, for example, be a 50:50 mixture of air and oxygen by volume. Other options are a 1:2 mixture of air and oxygen by volume, a 1:3 mixture of air and oxygen by volume, a 2:1 mixture of air and oxygen by volume and a 3:1 mixture of air and oxygen by volume.

[0146] In one embodiment of the present invention, the calcination of the present invention is carried out under a gas flow, such as pure oxygen and oxygen-enriched air (e.g., in the range of 3:1 to 10:1 oxygen:air by volume, measured at ambient temperature and ambient pressure). Such a gas flow may be referred to as a forced gas flow. Such a gas flow may have a flow rate of 0.5 to 15 m / s. 3 / h·kg According to the general formula Li 1+ x TM 1-x The specific flow rate of O2 is within a range of materials. The volume is measured under the following standard conditions: 298 Kelvin and 1 atmosphere. The gas stream can be used to remove gaseous cracking products (such as water and carbon dioxide).

[0147] In one embodiment of the present invention, the calcination according to the present invention has a duration in the range of 1 to 30 hours. Preferably, it is 10 to 24 hours. In this context, the time at a temperature above 600° C., the heating and holding time are taken into account, but the cooling time is ignored.

[0148] Another aspect of the present invention relates to a cathode active material, hereinafter also referred to as the cathode active material of the present invention. The cathode active material of the present invention can preferably be prepared from the precursor of the present invention.

[0149] The cathode active material of the present invention has the general formula Li 1+x TM 1-xO2, wherein x is in the range of -0.01 to +0.05, preferably +0.01 to 0.04, and has a span of particle size distribution (D90-D10) / D50 below 0.30, wherein TM comprises nickel and at least one metal selected from cobalt and manganese,

[0150] wherein the cathode active material has a total pore / intrusion volume in the range of 0.0035 to 0.01 ml / g as determined by N2 adsorption.

[0151] In one embodiment of the present invention, the cathode material of the present invention has a second shell comprising at least one oxide compound of W or B (eg, B2O3, LiBO2, Li2WO4, WO3, etc.). The second shell may be continuous or have an island structure.

[0152] The above spans refer to secondary particles. Secondary particles are formed by agglomerating substantially radially oriented primary particles. In this context, substantially radially aligned means that no more than 10% of the primary particles in a representative sample exhibit a deviation of 11° or less from ideal radial alignment, and includes particles that have perfect radial alignment with their primary particles. This determination can be made by analyzing SEM micrographs.

[0153] The span of the cathode active material of the present invention is less than 0.30, for example in the range of 0.10 to 0.28, preferably 0.18 to 0.26. The percentiles and medians of D10, D90 are preferably determined by light scattering or laser diffraction or electroacoustic spectroscopy, with laser diffraction being preferred.

[0154] The cathode active material of the present invention has a total pore / intrusion volume in the range of 0.033 to 0.1 ml / g, preferably 0.035 to 0.09 ml / g, and a pore size range of 20 to 100 μm. This is determined by N2 adsorption according to DIN 66134 (1998) when sample preparation for N2 adsorption measurement is done by degassing at 120°C for 60 minutes.

[0155] In a preferred embodiment, the average pore size of the cathode active material of the present invention is determined by N2 adsorption in the range of 50 to within the range.

[0156] In one embodiment of the present invention, the cathode active material of the present invention has an average secondary particle size D50 in the range of 2 to 20 μm, preferably 2 to 16 μm and even more preferably 10 to 16 μm.

[0157] In one embodiment of the present invention, TM is a combination of metals according to formula (I)

[0158] (Nia Co b Mn c ) 1-d M d (I)

[0159] in

[0160] a is in the range of 0.80 to 0.97, preferably 0.83 to 0.95,

[0161] b is zero or in the range of 0.025 to 0.2, preferably 0.025 to 0.15,

[0162] c is in the range of zero to 0.2, preferably zero to 0.15, or 0.01 to 0.15, and

[0163] d is in the range of zero to 0.1, preferably 0.03 to 0.05,

[0164] M is selected from the group consisting of Ti, Zr, Mo, W, Al, Mg, Nb, Sb and Ta,

[0165] a+b+c=1.

[0166] The cathode active material of the present invention is very suitable for producing lithium ion batteries and is especially suitable for use in cathodes of lithium ion batteries.

[0167] A further aspect of the present invention relates to an electrode and in particular to a cathode, hereinafter also referred to as the cathode of the present invention. The cathode of the present invention comprises

[0168] (A) at least one cathode active material according to the present invention,

[0169] (B) carbon in an electrically conductive form,

[0170] (C) at least one adhesive.

[0171] In a preferred embodiment of the present invention, the cathode of the present invention comprises

[0172] (A) 80 to 99% by weight of the cathode active material of the present invention,

[0173] (B) 0.5 to 19.5% by weight of carbon,

[0174] (C) 0.5% to 9.5% by weight of a binder polymer,

[0175] Percentages are relative to the sum of (A), (B), and (C).

[0176] The cathode according to the present invention contains conductive modified carbon, also referred to as carbon (B). Carbon (B) can be selected from soot, activated carbon, carbon nanotubes, graphene and graphite. Carbon (B) can be added as is during the preparation of the electrode material according to the present invention.

[0177] The electrodes according to the present invention may contain additional components. They may include a current collector (D), such as, but not limited to, aluminum foil. They further include a binder polymer (C), hereinafter also referred to as binder (C). The current collector (D) is not described further herein.

[0178] Suitable binders (C) are preferably selected from organic (co)polymers. Suitable (co)polymers, i.e., homopolymers or copolymers, can be selected, for example, from (co)polymers obtainable by anionic, catalytic, or free-radical (co)polymerization, and are particularly selected from polyethylene, polyacrylonitrile, polybutadiene, polystyrene, and copolymers of at least two comonomers selected from ethylene, propylene, styrene, (meth)acrylonitrile, and 1,3-butadiene. Polypropylene is also suitable. Polyisoprene and polyacrylates are also suitable. Polyacrylonitrile is particularly preferred.

[0179] In the context of the present invention, polyacrylonitrile is understood to mean not only polyacrylonitrile homopolymers but also copolymers of acrylonitrile with 1,3-butadiene or styrene. Polyacrylonitrile homopolymers are preferred.

[0180] In the context of the present invention, polyethylene is understood to mean not only homopolyethylene but also copolymers of ethylene, these copolymers comprising at least 50 mol % of copolymerized ethylene and up to 50 mol % of at least one further comonomer, for example α-olefins such as propylene, butene (1-butene), 1-hexene, 1-octene, 1-decene, 1-dodecene, 1-pentene, and also isobutene, vinylaromatics such as styrene, and also C1-C12 (meth)acrylic acid, vinyl acetate, vinyl propionate, C1-C13 (meth)acrylic acid, C1-C14 (meth)acrylic acid, C1-C16 (meth)acrylic acid, C1-C17 (meth)acrylic acid, C1-C18 (meth)acrylic acid, C1-C19 (meth)acrylic acid, C1-C20 (meth)acrylic acid, C1-C21 (meth)acrylic acid, C1-C19 (meth)acrylic acid, C1-C18 (meth)acrylic acid, C1-C19 ... 10 - alkyl esters, in particular methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, n-butyl acrylate, 2-ethylhexyl acrylate, n-butyl methacrylate, 2-ethylhexyl methacrylate, and also maleic acid, maleic anhydride and itaconic anhydride. The polyethylene may be HDPE or LDPE.

[0181] In the context of the present invention, polypropylene is understood to mean not only homopolypropylene but also copolymers of propylene, these copolymers comprising at least 50 mol% of copolymerized propylene and up to 50 mol% of at least one further comonomer, for example ethylene and α-olefins such as butene, 1-hexene, 1-octene, 1-decene, 1-dodecene and 1-pentene. The polypropylene is preferably isotactic or substantially isotactic.

[0182] In the context of the present invention, polystyrene is understood to mean not only homopolymers of styrene, but also C1-C12 copolymers with acrylonitrile, 1,3-butadiene, (meth)acrylic acid, (meth)acrylic acid, 10 - copolymers of alkyl esters, divinylbenzene, especially 1,3-divinylbenzene, 1,2-diphenylethylene and α-methylstyrene.

[0183] Another preferred binder (C) is polybutadiene.

[0184] Other suitable binders (C) are selected from polyethylene oxide (PEO), cellulose, carboxymethylcellulose, polyimide and polyvinyl alcohol.

[0185] In one embodiment of the present invention, the binder (C) is selected from the group consisting of binders having an average molecular weight M in the range of 50,000 to 1,000,000 g / mol, preferably to 500,000 g / mol. w Those (co)polymers.

[0186] The binder (C) may be a cross-linked or non-cross-linked (co)polymer.

[0187] In a particularly preferred embodiment of the present invention, binder (C) is selected from halogenated (to) polymers, especially fluorinated (to) polymers. Halogenated or fluorinated (to) polymers are understood to mean those (to) polymers comprising at least one (to) monomer having at least one halogen atom or at least one fluorine atom per molecule, more preferably at least two halogen atoms or at least two fluorine atoms per molecule. Examples are polyvinyl chloride, polyvinylidene chloride, polytetrafluoroethylene, polyvinylidene fluoride (PVdF), tetrafluoroethylene-hexafluoropropylene copolymer, vinylidene fluoride-hexafluoropropylene copolymer (PVdF-HFP), vinylidene fluoride-tetrafluoroethylene copolymer, perfluoroalkyl vinyl ether copolymer, ethylene-tetrafluoroethylene copolymer, vinylidene fluoride-chlorotrifluoroethylene copolymer and ethylene-chlorofluoroethylene copolymer.

[0188] Suitable binders (C) are especially polyvinyl alcohol and halogenated (co)polymers, for example polyvinyl chloride or polyvinylidene chloride, and especially fluorinated (co)polymers such as polyvinyl fluoride and especially polyvinylidene fluoride and polytetrafluoroethylene.

[0189] Another aspect of the present invention is an electrochemical cell comprising

[0190] (A) a cathode comprising the cathode active material (A) of the present invention, carbon (B) and a binder (C),

[0191] (B) an anode, and

[0192] (C) at least one electrolyte.

[0193] An embodiment of the cathode (1) has been described in detail above.

[0194] The anode (2) may contain at least one anode active material, such as carbon (graphite), TiO2, lithium titanium oxide, silicon or tin. The anode (2) may additionally include a current collector, such as a metal foil such as copper foil.

[0195] The electrolyte (3) may comprise at least one non-aqueous solvent, at least one electrolyte salt and optionally additives.

[0196] The nonaqueous solvent of the electrolyte (3) may be liquid or solid at room temperature and is preferably selected from polymers, cyclic or acyclic ethers, cyclic or acyclic acetals, and cyclic or acyclic organic carbonates.

[0197] Examples of suitable polymers are in particular polyalkylene glycols, preferably poly-C1-C4-alkylene glycols, and in particular polyethylene glycol. Here, the polyethylene glycol may contain up to 20 mol % of one or more C1-C4-alkylene glycols. The polyalkylene glycol is preferably a polyalkylene glycol with two methyl or ethyl end caps.

[0198] The molecular weight M of suitable polyalkylene glycols and in particular suitable polyethylene glycols is w It may be at least 400 g / mol.

[0199] The molecular weight M of suitable polyalkylene glycols and in particular suitable polyethylene glycols is w It may be up to 5,000,000 g / mol, preferably up to 2,000,000 g / mol.

[0200] Examples of suitable acyclic ethers are, for example, diisopropyl ether, di-n-butyl ether, 1,2-dimethoxyethane, 1,2-diethoxyethane, with 1,2-dimethoxyethane being preferred.

[0201] Examples of suitable cyclic ethers are tetrahydrofuran and 1,4-dioxane.

[0202] Examples of suitable acyclic acetals are, for example, dimethoxymethane, diethoxymethane, 1,1-dimethoxyethane and 1,1-diethoxyethane.

[0203] Examples of suitable cyclic acetals are 1,3-dioxane and in particular 1,3-dioxolane.

[0204] Examples of suitable acyclic organic carbonates are dimethyl carbonate, ethyl methyl carbonate and diethyl carbonate.

[0205] Examples of suitable cyclic organic carbonates are compounds of the general formula (II) and (III)

[0206]

[0207] where R 1 、R 2 and R 3 may be identical or different and are selected from hydrogen and C1-C4-alkyl, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl and tert-butyl, wherein R 2 and R 3 Preferably not all are tert-butyl.

[0208] In a particularly preferred embodiment, R 1 is methyl and R 2 and R 3 Each is hydrogen, or R 1 、R 2 and R 3 Each is hydrogen.

[0209] Another preferred cyclic organic carbonate is vinylene carbonate, formula (IV).

[0210]

[0211] The solvent(s) are preferably used in anhydrous state, ie with a water content in the range from 1 ppm to 0.1% by weight, which can be determined, for example, by Karl-Fischer titration.

[0212] The electrolyte (3) further comprises at least one electrolyte salt. Suitable electrolyte salts are in particular lithium salts. Examples of suitable lithium salts are LiPF6, LiBF4, LiClO4, LiAsF6, LiCF3SO3, LiC(C n F 2n+1 SO2)3, lithium imide such as LiN(C n F 2n+1 SO2)2, wherein n is an integer in the range of 1 to 20, LiN(SO2F)2, Li2SiF6, LiSbF6, LiAlCl4 and compounds having the general formula (C n F 2n+1 SO2) t Salts of YLi, wherein m is defined as follows:

[0213] When Y is selected from oxygen and sulfur, t=1,

[0214] When Y is selected from nitrogen and phosphorus, t=2, and

[0215] When Y is selected from carbon and silicon, t=3.

[0216] Preferred electrolyte salts are selected from LiC(CF3SO2)3, LiN(CF3SO2)2, LiPF6, LiBF4, LiClO4, among which LiPF6 and LiN(CF3SO2)2 are particularly preferred.

[0217] In a preferred embodiment of the present invention, the electrolyte (3) contains at least one flame retardant. Useful flame retardants can be selected from trialkyl phosphates (the alkyl groups are different or the same), triaryl phosphates, alkyl dialkyl phosphonates, and halogenated trialkyl phosphates. Preferred are tri-C1-C4-alkyl phosphates (the C1-C4-alkyl groups are different or the same), tribenzyl phosphate, triphenyl phosphate, C1-C4-alkyl di-C1-C4-alkyl phosphonates, and fluorinated tri-C1-C4-alkyl phosphates.

[0218] In a preferred embodiment, the electrolyte (3) comprises at least one flame retardant selected from trimethyl phosphate, CH3-P(O)(OCH3)2, triphenyl phosphate and tris-(2,2,2-trifluoroethyl)-phosphate.

[0219] The electrolyte (3) may contain 1 to 10% by weight of a flame retardant based on the total amount of the electrolyte.

[0220] In an embodiment of the present invention, the battery according to the invention comprises one or more separators (4) by means of which the electrodes are mechanically separated. Suitable separators (4) are polymer films, in particular porous polymer films, which are non-reactive towards metallic lithium. Particularly suitable materials for the separators (4) are polyolefins, in particular film-forming porous polyethylene and film-forming porous polypropylene.

[0221] The membrane (4) made of polyolefin, in particular polyethylene or polypropylene, can have a porosity in the range of 35% to 50%. Suitable pore sizes are, for example, in the range of 30 to 500 nm.

[0222] In another embodiment of the present invention, the separator (4) can be selected from PET nonwovens filled with inorganic particles. Such a separator can have a porosity in the range of 40% to 55%. Suitable pore sizes are, for example, in the range of 80 to 750 nm.

[0223] The battery according to the invention may further comprise a housing, which may have any shape, for example the shape of a cubic or cylindrical disk. In one variant, a metal foil configured as a pouch is used as the housing.

[0224] The battery according to the invention provides very good discharge and cycling behavior, in particular at high temperatures (45° C. or higher, for example up to 60° C.), in particular with regard to capacity loss.

[0225] The battery according to the invention may comprise two or more electrochemical cells combined with one another, which may be connected in series or in parallel, for example. A series connection is preferred. In the battery according to the invention, at least one of the electrochemical cells comprises at least one electrode according to the invention. Preferably, in the electrochemical cells according to the invention, the majority of the electrochemical cells comprise an electrode according to the invention. Even more preferably, in the battery according to the invention, all electrochemical cells comprise an electrode according to the invention.

[0226] The present invention further provides for the use of a battery according to the invention in a device, in particular in a mobile device. Examples of mobile devices are vehicles, such as cars, bicycles, airplanes or water vehicles (such as boats or ships). Other examples of mobile devices are those that are moved manually, such as computers (especially laptops), telephones, or electric hand tools (for example in the construction industry), in particular drills, battery-powered screwdrivers or battery-powered staplers.

[0227] The present invention is further illustrated by working examples and accompanying drawings.

[0228] General Notes:

[0229] The experimental example used a cascade of three 3.2-liter stirred tank reactors made of glass and each equipped with baffles and a two-stage four-bladed pitch turbine (45° angle, diameter: 0.06 m). Each stirred tank reactor was also equipped with a settling device and an overflow pipe, via which the mother liquor was withdrawn from the reactor.

[0230] All pH values were measured at 23°C.

[0231] rpm: revolutions per minute

[0232] The total solids content was determined by H2SO4 dissolution of an aliquot of the corresponding suspension and subsequent ICP analysis of Ni, Co, and Mn.

[0233] Figure 1 : Cascade of three stirred tank reactors, each equipped with an overflow system, clarifier, baffles, and two buffer tanks

[0234] Figure 2 : A cascade of three stirred tank reactors, each equipped with an overflow system, baffles, and two buffer tanks. The second and third stirred tank reactors are equipped with clarifiers, while the first stirred tank reactor has no clarifier.

[0235] I. Preparation of Precursors

[0236] I.1 Production of the (oxy)hydroxide P-CAM.1 and dehydrated oxy-P-CAM.1 according to the invention

[0237] Step (a.1):

[0238] The following aqueous solutions are available:

[0239] Solution (α1.1): NiSO4, CoSO4 and MnSO4 dissolved in deionized water, molar ratio 91:4.5:4.5, total transition metal concentration: 1.45 mol / kg

[0240] Solution (β1.1): 25wt% NaOH dissolved in deionized water

[0241] Solution (γ1.1): 25 wt% ammonia in deionized water

[0242] Unless expressly stated otherwise, percentages are % by weight.

[0243] Before step (b.1)

[0244] The first stirred tank reactor of the cascade was charged with 2.7 liters of deionized water and heated to 55° C. with stirring at 500 rpm (average specific energy input: 0.63 W / l). 165 g of solution (γ.1) were then added, and the pH was adjusted to 12.45 by addition of solution (β.1).

[0245] Step (b.1):

[0246] Subsequently, the stirrer speed was adjusted to 750 rpm (16 W / l) and the simultaneous feeding of solutions (α1.1), (β1.1) and (γ1.1) was started. The stirrer speed was kept constant during step (b.1). The total flow was adjusted in such a way that the ratio between the reactor volume (3.2 l) and the total volume flow rate reached 10 hours (residence time equivalent). The temperature was kept constant at 45 ° C. The molar feed ratio between ammonia and TM was set to 0.25 and kept constant during step (b.1). The pH value was adjusted to 11.5. The mother liquor was continuously withdrawn from the reaction system to increase the solid content. Step (b.1) had a duration of 47 h, which produced a slurry with a solid content of 427 g / l in the stirred tank reactor (excluding the clarifier).

[0247] All feed flows were stopped and the suspension from the reactor and the clarifier was discharged into a stirred suspension buffer vessel.The suspension contained slurried particles with an average particle size (d50) of 4.3 μm and a span of 0.7.

[0248] Step (c.1)

[0249] The second reactor of the cascade was charged with 2.6 liters of deionized water and heated to 55° C. under stirring (500 rpm, specific energy input: 0.65 W / l). 83 g of solution (γ2.1) were added. 530 g of the suspension from step (b.1) were then added to the reactor. The solids content at the start of step (e.1) was 52 g / l.

[0250] Step (d.1):

[0251] The following aqueous solutions are available:

[0252] Solution (α2.1): NiSO4, CoSO4 and MnSO4 dissolved in deionized water, molar ratio 91:4.5:4.5, total transition metal concentration: 1.45 mol / kg

[0253] Solution (β2.1): 25 wt% NaOH dissolved in deionized water

[0254] Solution (γ2.1): 25 wt% ammonia in deionized water

[0255] The corresponding solutions (α2.1), (β2.1) and (γ2.1) in step (g.1) have the same composition.

[0256] Step (e.1)

[0257] Subsequently, the solutions (α2.1), (β2.1) and (γ2.1) were fed simultaneously. The molar feed ratio between ammonia and TM was set to 0.35 and kept constant. During step (e), the temperature was kept constant at 55°C. The pH was adjusted to 11.5 and then kept constant at this value until the end of step (e.1). The ratio between the reactor volume (3.2 liters) and the total volume flow of the feed (residence time equivalent) was calculated starting at 33 hours, and the feed was gradually increased to a residence time equivalent of five hours during the synthesis. During the batch process, the rotation speed of the agitator was gradually reduced to a final agitator speed of 780 rpm (2.25 W / l). The agitator characteristic curve was designed in such a way that the average specific energy input during step (e.1) was 3.7 W / l. The mother liquor was continuously withdrawn from the tank reactor to increase the solids content. The complete duration of step (e.1) was 20 hours, and a slurry with a total solids content of 304 g / l was produced in the reactor. After the batch was complete, all feed flows were stopped and the resulting suspension from the reactor and clarifier was discharged into a stirred suspension buffer vessel.The particles in the suspension had an average particle size (d50) of 7.3 μm and a span of 0.53.

[0258] Step (f.1)

[0259] 2.3 liters of deionized water were added to the third stirred tank reactor of the cascade and heated to 55° C. at 500 rpm (0.68 W / L) under stirring. 83 g of solution (γ2.1) and 940 g of the suspension from step (e.1) were then added to the tank reactor. The resulting slurry had an initial solids content of 76 g / L.

[0260] Step (g.1)

[0261] The stirrer speed was adjusted to 800 rpm (1.9 W / l) and the simultaneous addition of solutions (α2.1), (β2.1) and (γ2.1) was started. During step (g.1), the temperature was kept constant at 55°C. During step (g.1), the molar feed ratio between ammonia and TM was maintained at 0.35. The pH was adjusted to 11.5 within the first hour and remained constant during step (g.1). The ratio between the reactor volume (3.2 l) and the total volume flow rate (residence time equivalent) of the feed was calculated starting at 33 hours. Then, during step (g.1), the feed was gradually increased to a final residence time equivalent of 5 hours. The feed profile was designed with an average residence time of 5.8 hours. During step (g.1), the rotational speed of the stirrer was gradually reduced to a final stirrer speed of 550 rpm (0.7 W / l), so the average value was 1.4 W / l. The mother liquor was continuously withdrawn through a clarifier to increase the solids content. The complete duration of step (g.1) was 21.2 hours. A slurry with a solids content of 347 g / l was obtained. All feed flows were stopped and the resulting suspension from the reactor and clarifier was discharged into a stirred suspension buffer vessel.

[0262] Post-processing:

[0263] The slurry from step (g.1) was filtered. The resulting filter cake was washed with deionized water and then with aqueous sodium hydroxide solution (1 kg 25 wt% aqueous sodium hydroxide solution / kg solid hydroxide).

[0264] The filter cake was dried in a cabinet dryer at 120°C for 12 hours to obtain the mixed metal (oxy)hydroxide P-CAM.1. P-CAM.1 had an average particle size (D50) of 14.4 μm, a span of 0.23, and a particle diameter of 19.2 μm. 2 The BET surface area is 2.33 × 10-15 mm / m2, the average shape factor is 0.991, and the pore volume measured by N2 adsorption is 0.048 ml / g.

[0265] Oxygen-P-CAM.1

[0266] The P-CAM.1 of the present invention was heated in a Linn oven at 450°C for 2 hours under flowing air to obtain the mixed metal oxide oxy-P-CAM. 1. The oxy-P-CAM.1 of the present invention had an average particle size (D50) of 14.3 μm, a span of 0.23 and a diameter of 97.6 m. 2 The BET surface area is 2.33 × 10-11.87 mm / s. The average shape factor reaches 0.990. The pore volume measured by N2 adsorption is 0.211 ml / g.

[0267] I.2 Preparation of comparative (oxy)hydroxide CP-CAM.1 and comparative dehydrated oxy-CP-CAM.1

[0268] Repeat steps (a.1), (b.1), (c.1), and (d.1).

[0269] Step C-(e.2)

[0270] Subsequently, the simultaneous feeding solutions (α2.1), (β2.1) and (γ2.1) were started. The molar feed ratio between ammonia and TM was set to 0.35 and kept constant. During step (g), the temperature was kept constant at 55°C. The pH value was adjusted to 11.5 and then kept constant at this value until step C-(e.2) ended. The stirring speed was adjusted to 1200rpm (6.3W / l). The ratio between the reactor volume (3.2 liters) and the total volume flow of the feed (residence time equivalent) was calculated starting from 33 hours, and the feed was gradually increased to a residence time equivalent of 5 hours during the synthesis. During the batch process, the rotational speed of the agitator was gradually reduced to a final agitator speed of 550rpm (0.7W / l). The agitator characteristic curve was designed in such a way that the average specific energy input during step C-(e.2) was 2.4W / l. The mother liquor was continuously withdrawn from the tank reactor to increase the solids content. The complete duration of step C-(e.2) was 20 hours and produced a slurry with a total solids content of 304 g / l in the reactor. After the batch was completed, all feed flows were stopped and the final suspension from the reactor and clarifier was discharged into a stirred suspension buffer vessel. The particles in the suspension had an average particle size (d50) of 14.3 μm and a span of 0.38.

[0271] Neither step (f) nor (g) is performed.

[0272] Post-processing:

[0273] The slurry from step C-(e.2) was filtered. The resulting filter cake was washed with deionized water and then with aqueous sodium hydroxide solution (1 kg 25 wt% aqueous sodium hydroxide solution / kg solid hydroxide).

[0274] The filter cake was dried in a cabinet dryer at 120°C for 12 hours to obtain mixed metal (oxy)hydroxide CP-CAM.2. CP-CAM.2 had an average particle size (D50) of 14.2 μm, a span of 0.35, and a particle size of 21.2 μm. 2 The BET surface area is 2.33 × 10-15 mm / m2, the average shape factor is 0.972, and the pore volume measured by N2 adsorption is 0.029 ml / g.

[0275] Oxygen-CP-CAM.2

[0276] CP-CAM.2 was heated in a Linn oven at 450°C for 2 hours under flowing air to obtain the mixed metal oxide oxy-P-CAM.2. The comparative precursor oxy-P-CAM.2 had an average particle size (D50) of 14.0 μm, a span of 0.35 and a diameter of 95.5 μm. 2 The BET surface area of ​​the composite is ​​1.5477 / g and the average shape factor reaches 0.971.

[0277] The pore volume determined by N2 adsorption was 0.082 ml / g.

[0278] Table 1 summarizes the properties of the inventive and comparative precursors.

[0279] Table 1: Precursors of the present invention and comparative precursors

[0280] D50[μm] span[-] <![CDATA[BET[m 2 / g]]]> Pore volume [ml / g] Form Factor [-] P-CAM.1 14.4 0.23 19.2 0.048 0.991 CP-CAM.2 14.2 0.35 21.2 0.029 0.972 Oxygen-P-CAM.1 14.3 0.23 97.6 0.211 0.990 Oxygen-CP-CAM.2 14.0 0.35 95.6 0.082 0.971

[0281] II. Preparation of Cathode Materials of the Invention and Comparative Cathode Materials

[0282] II.1 Calcination and post-treatment of the precursors of the invention

[0283] 30 g of oxy-P-CAM.1 was mixed with LiOH monohydrate (molar ratio Li / metal = 1.04), 133 mg of TiO2, and 122 mg of ZrO2 in a mill for 15 minutes. The resulting mixture was placed in a sagger and transferred to a Linn oven. The temperature was increased to 750°C at a rate of 2°C / min under flowing oxygen and then held constant at 750°C for 8 hours, followed by natural cooling under flowing oxygen. The resulting powder was then deagglomerated in the mill and sieved.

[0284] 30 g of the powder was then added to 15 ml of deionized water, stirred for 2 minutes, and then immediately filtered on a Buchner funnel to remove the water. The wet cake was then dried at 120° C. under a reduced pressure N 2 atmosphere for 10 hours.

[0285] The resulting powder was then dry-coated with boric acid by mixing 30 g of powder, a mixing medium, and 30 mg of boric acid on a roller mill at low speed for 40 minutes. The dried powder was placed in a sagger and heat-treated in a Linn oven. The Linn oven was heated to 300°C for 2 hours under an oxygen atmosphere and allowed to cool naturally. A CAM.1 of the present invention was obtained with a (D50) of 14.3 μm, a span of 0.22, and an average shape factor of 0.993. The pore volume of CAM.1 was 0.0044 ml / g.

[0286] II.2 Preparation of comparative cathode active materials

[0287] The comparative oxide O-C-PCAM.2 was treated in the same manner to obtain C-CAM.2 having a (D50) of 14.0 μm, a span of 0.34 and an average shape factor of 0.975. The pore volume of C-CAM.2 was 0.0031 ml / g.

[0288] III. Testing of cathode active materials

[0289] III.1 Cathode manufacturing

[0290] Positive electrode: PVDF binder (polyvinylidene fluoride, 5130) was dissolved in NMP (Merck) to produce a 7.5 wt.% solution. For the preparation of the electrodes, the binder solution (3 wt.%), graphite (SFG6L, 2 wt.%) and carbon black (Super C65, 1 wt.-%) were suspended in NMP. After mixing using a planetary centrifugal mixer (ARE-250, Thinky Corp., Japan), CAM.1 or C-CAM.2 according to the invention (94 wt.%) was added and the suspension was stirred again to obtain a lump-free slurry. The solid content of the slurry was adjusted to 65%. The slurry was coated on Al foil using a KTF-S roll-to-roll coater (Mathis AG). All electrodes were calendered before use. The thickness of the cathode material was 70 μm, corresponding to 15 mg / cm 2 Before cell assembly, all electrodes were dried at 105 °C for 7 h.

[0291] III.2 Electrolyte production

[0292] A base electrolyte composition was prepared containing 12.7 wt% LiPF6, 26.2 wt% ethylene carbonate (EC), and 61.1 wt% ethyl methyl carbonate (EMC) (EL host 1) (based on the total weight of EL host 1). To this base electrolyte formulation was added 2 wt.% vinylene carbonate (VC) (EL host 2).

[0293] III.3 Test Cell Fabrication – Coin-Type Half-Cell

[0294] A coin-type half-cell (20 mm in diameter and 3.2 mm thick) containing the cathode prepared as described under II.1.1 and lithium metal as the working and counter electrodes, respectively, was assembled and packaged in an Ar-filled glove box. Furthermore, the cathode, anode, and separator were stacked in the order cathode / / separator / / Li foil to produce a half-coin-cell. Thereafter, 0.15 mL of the EL matrix 1 described above (III.2) was introduced into the coin-cell.

[0295] III.4 Battery Cell Performance Evaluation

[0296] The initial performance, C-rate performance and cycle performance were measured as follows: The button half-cell according to II.3 was tested at room temperature in the voltage range between 4.3 V and 2.8 V. For the initial cycles, an initial lithiation was carried out in CC-CV mode (i.e. a constant current (CC) of 0.1 C was applied) until 4.3 V was reached, followed by a CV step until the current dropped to 0.01 C. After a 10 min rest time, a reduction lithiation was carried out at a constant current of 0.1 C up to 2.8 V. For the C-rate test, the charge and discharge rates were adjusted accordingly. For the cycle test, the constant current was chosen to be 1 C until 100 cycles were reached. The results are summarized in Table 2.

[0297] Table 2: Physical and electrochemical data of cathode active materials. Pressed density was measured at 250 MPa.

[0298]

Claims

1. A process for the production of a granular (oxy)hydroxide or oxide of TM, wherein TM represents a metal, wherein TM comprises nickel and at least one metal selected from the group consisting of cobalt and manganese, and wherein the nickel content of TM is at least 80 mol-%, wherein the process is carried out in a cascade of at least three stirred tank reactors and comprises the following steps: (a) providing an aqueous solution (α1) containing Ni and optionally at least one water-soluble salt of a metal selected from cobalt and manganese, an aqueous solution (β1) containing an alkali metal hydroxide, and optionally an aqueous solution (γ1) containing a complexing agent selected from ammonia, glycine, tartrate, citrate and oxalate, (b) mixing solution (α1) with solution (β1) and, if applicable, solution (γ1) in a first stirred tank reactor at a pH in the range of 11.0 to 13.5 and at an average energy input in the range of 8 to 20 W / l, thereby producing slurried solid particles of the hydroxide of TM, (c) transferring the particles from step (b) as a slurry into a second stirred tank reactor, (d) providing an aqueous solution (α2) containing Ni and a water-soluble salt of at least one metal selected from cobalt and manganese, and an aqueous solution (β2) containing an alkali metal hydroxide, and optionally an aqueous solution (γ2) containing a complexing agent selected from ammonia, glycine, tartrate, citrate and oxalate, (e) combining solution (α2) with solution (β2) and, if applicable, solution (γ2) in said second stirred tank reactor at a pH in the range of 10.5 to 12.0 and at an average specific energy input in the range of 2 to 8 W / l and lower by a factor of 0.20 to 0.75 than in step (b), thereby growing solid particles of the hydroxide of TM, (f) transferring the particles from step (e) as a slurry into a third stirred tank reactor, (g) combining solution (α2) with solution (β2) and, if applicable, solution (γ2) in said third stirred tank reactor at a pH value in the range of 10.5 to 12.0, wherein the average specific energy input in step (g) is in the range of 0.5 to 2 W / l and is lower than in step (e) by a factor of 0.20 to 0.75, and wherein the pH is measured at 23°C.

2. The method according to claim 1, wherein The initial solids content at the start of the stages increases from step (b) to step (e) to step (g).

3. The method according to claim 1 or 2, wherein: The particulate (oxy)hydroxide is selected from the group consisting of hydroxides, oxyhydroxides and oxides of TM, wherein TM is a combination of metals according to the general formula (I): (Ni a Co b Mr c ) 1-d M d (I) in a is in the range of 0.80 to 0.97, b is zero or in the range of 0.025 to 0.2, c is in the range of zero to 0.2, and d is in the range of zero to 0.1, M is selected from the group consisting of Mg, Al, Ti, Zr, Mo, W, Nb, Sb and Ta, a+b+c=1, and b+c>zero.

4. A method according to any one of the preceding claims, wherein Step (g) is carried out in a draft tube reactor.

5. A method according to any one of the preceding claims, wherein In two of steps (b), (e) and (g), mother liquor is withdrawn from the reactors.

6. The process according to any one of the preceding claims, comprising the additional step (h) of isolating the particulate (oxy)hydroxide by a solid-liquid separation method and subsequently drying.

7. The method according to claim 6, wherein: The method comprises a heating step (i) at a temperature in the range of 400°C to 550°C in the absence of a lithium compound.

8. A granular (oxy)hydroxide of a TM having a core-shell structure and a span of the particle size distribution (D90-D10) / D50 of less than 0.30, wherein the TM comprises nickel and at least one metal selected from cobalt and manganese, and wherein the nickel content of the TM is at least 80 mol-%, and wherein the particles consist of primary particles and have a core and a shell and concentric layers between the core and the shell, wherein the density of the concentric layers is higher than the density of the core and the shell, and wherein the particulate (oxy)hydroxide has a total pore / intrusion volume in the range of 0.033 to 0.1 ml / g as determined by N2 adsorption.

9. A particulate oxide of TM having a core-shell structure and a span of particle size distribution (D90-D10) / D50 of less than 0.30, wherein the TM comprises nickel and at least one metal selected from cobalt and manganese, and wherein the nickel content of the TM is at least 80 mol-%, and wherein the particles consist of primary particles, And wherein the particulate oxide has a total pore / intrusion volume in the range of 0.1 to 0.5 ml / g as determined by N2 adsorption.

10. The granular (oxy)hydroxide or oxide according to claim 8 or 9, having a particle size of 2 to 120 m 2 The specific surface area according to BET is in the range of 1.5-2.5 μg / g.

11. The particulate (oxy)hydroxide or oxide according to any one of claims 8 to 10, having an average shape factor of 0.98 or greater.

12. The granular (oxy)hydroxide or oxide according to any one of claims 8 to 11, wherein TM is a combination of metals according to formula (I) a is in the range of 0.80 to 0.97, b is zero or in the range of 0.025 to 0.2, c is in the range of zero to 0.2, and d is in the range of zero to 0.1, M is selected from the group consisting of Mg, Al, Ti, Zr, Mo, W, Nb, Sb and Ta, a+b+c=1, and b+c>zero.

13. A method for producing a cathode active material for a lithium ion battery, the method comprising the steps of: The particulate (oxy)hydroxide or oxide according to any one of claims 8 to 12 is mixed with a lithium source and a dopant optionally selected from oxides or (oxy)hydroxides of Nb, Ti, Ta, Zr, Al, Mg or W, and the resulting mixture is calcined at a temperature in the range of 600°C to 1000°C.

14. A cathode active material having the general formula Li 1+x TM 1-x O2 and having a core-shell structure and a span of particle size distribution (D90-D10) / D50 of less than 0.30, wherein x is in the range of -0.01 to +0.05, wherein the TM comprises nickel and at least one metal selected from cobalt and manganese, wherein the nickel content of the TM is at least 80 mol-%, wherein the cathode active material has a total pore / intrusion volume in the range of 0.0035 to 0.01 ml / g as determined by N2 adsorption.

15. The cathode active material according to claim 14, wherein The cathode material has a second outer shell comprising at least one W or B oxide compound.

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