Phosphonate polyamines as dispersing agent for water-based electrodes in batteries

Abstract

A composition, comprising a phosphonated polyamine, wherein the phosphonated polyamine has a molar ratio C:P of ≥ 2.8. An aqueous dispersion, an electrochemical device, use of the composition to disperse a particulate in an aqueous solvent, use of the composition in production of an additive, use of the composition in the composition of electrode are also provided.

Description

[0001] Phosphonate polyamines as dispersing agent for water-based electrodes in batteries

[0002] Technical Field

[0003] The invention relates to a dispersing agent for water-based electrodes in batteries.

[0004] Background art

[0005] Dispersing of carbon and / or carbon-coated particles in aqueous solvent is proven to be difficult, especially when the specific surface area of the given particles is high. Such dispersions constitute the standard method to produce slurries to afford electrodes in lithium-ion batteries (LiB). Particles with increased surface area give clear advantages, i.e. better electron conductivity, but are more difficult to disperse. A system which is not properly dispersed will have drawbacks such as instability, poor homogeneity, high viscosity.

[0006] EP2889335A1 discloses an aqueous liquid composition including a water-based medium containing water, a polymer having at least one type of groups selected from hydroxyl groups and amino groups, and phosphonobutane tricarboxylic acid (PBTC). The polymer is at least one polymer selected from the group consisting of a polysaccharide, polyamino acid, polyvinyl alcohol, polyallylamine, polyvinylamine, a polyamidine, a polyethyleneimine, and their derivatives. Owing to the inclusion of the OH / NH2 polymer and PBTC equipped with binding ability and dispersing ability for a filler such as a conductive material, hydrophilicity and the like, the aqueous liquid composition is also excellent in environmental performance while retaining binding properties and dispersion properties for the filler and functionality such as hydrophilicity. Further, owing to the inclusion of an appropriate amount of water, preferably a water-based medium containing water and an organic solvent such as a water-soluble alcohol as a solvent or dispersion medium, the OH / NH2 polymer and PBTC are prevented from precipitation and adequate viscosity is retained. Hence, the aqueous liquid composition assures a pot life upon coating, prevents the settling-out of the filler, and realizes coatability and dispersion stability.

[0007] JOU, Kiyokazu, "Technological Development of Dispersing Agents for Water Borne Coating Materials", JETI, 44 (10), pp. 110-112 (1996) discloses a dispersant for use in the water-based slurry, a polycarboxylate salt or phosphate amine salt used in the field of paints.

[0008] Preparation of a-aminomethylphosphonic acids with H3PO3, HCHO, and amines is known. For example, Kurt Moedritzer and Riyad R. Irani, The Journal of Organic Chemistry 1966 31 (5), 1603-1607 disclosed a direct reaction to prepare a- aminomethylphosphonic acids, R3-nN[CH2P(O)(OH)2]n, from orthophosphorous acid (also called phosphorous acid, H3PO3), HCHO, and amines. The amines employed in this reaction are ammonia, primary or secondary amines, polyamines, and functionally substituted amines. The a-aminomethylphosphonic acids prepared exhibit chelating properties for polyvalent metal ions.

[0009] CN1803590A discloses a method to prepare lithium iron phosphate as anode material of a lithium ion battery, comprising dissolving iron salt, lithium salt, nitrate of doping element and conductive agent or precursor of conductive agent in water solution of chelating agent containing phosphorus, stirring at 50-100 deg.C to remove water, placing into high temperature furnace, in nitrogen, argon or hydrogen-argon mixed gas atmosphere, heating at a heating rate of 5-30 deg.C / min, calcining at 450-750 deg.C for 20-600min, then cooling to room temperature to obtain the lithium iron phosphate as the anode material of the lithium ion battery, wherein the concentration of the aqueous solution of the phosphorus-containing chelating agent is 40-60 wt.%. The phosphorus-containing chelating agent include aminotrimethylene phosphonic acid, diethylenetriaminepentamethylene phosphonic acid, hydroxyethylidene diphosphonic acid, 2-hydroxyphosphonoacetic acid, and polyamino polyether methylene phosphonate. The phosphorus-containing chelating agent is not a dispersing agent and the document did not disclose use of the phosphorus- containing chelating agent as a dispersing agent, let alone how to disperse carbon and / or carbon-coated particles in aqueous solvent.

[0010] Summary of the invention

[0011] The objective of the invention is to provide a novel phosphonated polyamine-based additive useful as a dispersing agent to disperse water-insoluble particles including carbon and / or carbon-coated particles, in an aqueous (or water-based) solvent, in particular to obtain a stable dispersion.

[0012] The invention provides a phosphonated amine, particularly a phosphonated polyamine. The phosphonated amine contains nitrogen groups functionalized with phosphate groups which improves the dispersion of carbon and / or carbon coated particles without deteriorating the stability of the dispersion itself.

[0013] The invention further provides use of the phosphonated amine of the invention as a dispersant. The dispersant is particularly useful to disperse particles such as carbon or carbon-coated particles in an aqueous solvent, especially to prepare a stable aqueous (or water-based) dispersion.

[0014] As used herein, the term “stable” means that a suspension can remain homogenous at least 24 hours without optically visible formation of phase separation or precipitation via visual inspection.

[0015] The invention further provides a composition, especially a dispersant composition, comprisingthe phosphonated amine of the invention. In particular, the invention provides a composition, especially a dispersant composition, comprising: the phosphonated polyamine of the invention; wherein the phosphonated polyamine has a molar ratio C:P of^2.8.

[0016] Preferably, the composition is a dispersant.

[0017] The phosphonated polyamines of the invention include: phosphonated polyetheramines, and phosphonated polyalkyleneimines including phosphonated branched polyalkyleneimines and phosphonated linear polyalkyleneimines.

[0018] As used herein, the term “phosphonated polyamines” refers to phosphonated product of polyamines, wherein the polyamine contains at least two primary amino groups.

[0019] The phosphonated polyamines also include salts thereof. The term “salt” herein refers to any protonated or deprotonated form and may also include to the “inner salt” (by intramolecular transfer of protons from the acid groups to amino groups). Examples of suitable salt cation include sodium ion, potassium ion, ammonium ion, etc.

[0020] The phosphonated amine may be a-aminomethylphosphonic acids.

[0021] The phosphonated amine may be prepared by phosphonation of an amine, in particular by phosphonating an amine, preferably a polyamine, such as polyetheramines with primary amino group, branched polyalkyleneimines with primary amino group and linear polyalkyleneimines with primary amino group, via aqueous phospha-Mannich reaction, for example with H3PO3. In some embodiments, the phosphonated amine is prepared by aqueous phospha-Mannich reaction of a polyamine with H3PO3 and formaldehyde.

[0022] The phosphonated amine has -P-CH2-N- structures. In some embodiments, the phosphonated amine has 3 to 300, such as 3 to 250, 3 to 200, 3 to 150, 3 to 100, 3 to 90, 3 to 80, 3 to 70, 3 to 60, 3 to 50, 3 to 40, 3 to 30, especially 3 to 60, or 3 to 30, for example, 4, 5, 6, 7, 8, 9, 10, 11 , 12, 13, 14, 15, 16, 17, 18, 19, 20, 21 , 22, 23, 24, 25, 26, 27, 28, or 29 -P-CH2-N- structures.

[0023] It should be understood that the term “-P-CH2-N- structure” refers to the part of a molecular structure that has a structure of “-P-CH2-N-”, wherein the P atom is further attached to other atoms, such as 3 oxygen atoms, and the N atom is further attached to other atoms, such as 2 carbon atoms. Typically, the “-P-CH2-N- structure” forms a “H2O3P-CH2-N-” structure wherein the N atom is further attached to two carbon atoms. In some embodiments, two “-P-CH2-N- structures” share one N atom and form a “-P-CH2-N-CH2-P-” structure, wherein the N is further attached to another atom such as a carbon atom. In such cases, the two “-P-CH2-N- structures” form a “H2O3P-CH2-N-CH2-PO3H2” structure wherein the N atom is further attached to one carbon atom.

[0024] The phosphonated polyamine may be a compound represented by any one of general structure formulas below, or the salts thereof: wherein residue A each independently represents either a hydrogen atom, an alkyl group with 1-4 carbon atoms, or -CH2-P(=O)(OH)2; n represents a number from 2 to 100, preferably 5 to 70, such as 5 to 60, 5 to 50, 5 to 40, 5 to 30, 5 to 20, for example 3, 4, 5, 6, 7, 8, 9, 10, 11 , 12, 13, 14, 15, 16, 17, 18, 19, 20; especially 5;

[0025] R represents hydrogen, methyl, ethyl, or n-propyl; preferably methyl; m represents a number from 1 to 7, preferably 1 to 5, for example, 1 , 2, 3, 4, or 5, especially 5; o represents a number from 1 to 20, preferably from 1 to 10, most preferably from 1 to 6, for example, 1 , 2, 3, 4, or 5; especially 1 ; with the proviso that on average the polyamines contain at least two -CH2- P(=O)(OH)2 groups per molecule.

[0026] For example, the phosphonated polyamine may have 3 to 300, such as 3 to 250, 3 to 200, 3 to 150, 3 to 100, 3 to 90, 3 to 80, 3 to 70, 3 to 60, 3 to 50, 3 to 40, 3 to 30, especially 3 to 30, for example, 4, 5, 6, 7, 8, 9, 10, 11 , 12, 13, 14, 15, 16, 17, 18, 19, 20, 21 , 22, 23, 24, 25, 26, 27, 28, or 29 -CH2-P(=O)(OH)2groups per molecule.

[0027] The phosphonated branched polyalkyleneimine is prepared by phosphonation of a branched polyalkyleneimine via aqueous phospha-Mannich reaction with H3PO3 and formaldehyde. Partly due to the complex structure of the branched polyalkyleneimine raw material, the manifold nature of the structural variations of the phosphonated branched polyalkyleneimine product does not permit any clear description in terms of formula. Therefore, the formula (III) is a representative formula of the prepared phosphonated branched polyalkyleneimine. In addition, the structure between the dotted lines in formula (III) shows only a part of the entire polymer structure and the dotted line means that the polymer structure shown is attached to the rest of the phosphonated branched polyethyleneimine chain, wherein the phosphonation of the rest of the phosphonated branched polyethyleneimine chain exists in the same positions of the shown formula (III), in particular the amine groups of the branched polyethyleneimine chain.

[0028] The phosphonated polyamine of formula (I) is a phosphonated polyetheramine. The phosphonated polyamine of formula (II) is a linear phosphonated polyalkyleneimine. The phosphonated polyamine of formula (III) is a phosphonated branched polyethyleneimine.

[0029] The phosphonated branched or linear polyethyleneimine may be a compound represented by the formula XpAp+2, or the salts thereof, wherein

[0030] X represents p represents a number 2, preferably ^3; A represents H, alkyl with 1 to 4 carbon atoms, or -CH2P(=O)(OH)2, wherein the dotted lines denote either a single bond to a unit A or a C-N single bond to a unit X, with the proviso that on an average at least two -CH2-P(=O)(OH)2 groups are contained per molecule.

[0031] The phosphonated branched or linear polyethyleneimine may be a compound comprising or consisting of units X and units A, or the salts thereof, wherein

[0032] X represents the number of unit X is at least 2, preferably at least 3;

[0033] A represents H, alkyl with 1 to 4 carbon atoms, or -CH2P(=O)(OH)2, wherein the dotted lines denote either a single bond to a unit A or a C-N single bond to a unit X, and wherein each X and each A has at least one single bond to a unit X, with the proviso that on an average at least two -CH2-P(=O)(OH)2 groups are contained per molecule.

[0034] Preferably, the phosphonated branched or linear polyethyleneimine contains an average at least three X per molecule.

[0035] The phosphonated linear polyethyleneimine may be a compound represented by the formula below, or the salts thereof, wherein

[0036] A represents H, alkyl with 1 to 4 carbon atoms, or -CH2P(=O)(OH)2; q represents a number 2, preferably ^3; each repeat unit X, i.e. the part in the brackets, has at least one C-N single bond to another unit X; the two terminal X units have one C-N-single bond to the X neighbour; and the remaining units X have two C-N single bonds to both X neighbours.

[0037] The phosphonated polyalkyleneimines with primary amino groups particularly include phosphonated branched or linear polyethyleneimines. The inventors surprisingly found that the composition or phosphonated amines of the invention has a good dispersing effect in aqueous systems and may be used as a dispersant in aqueous systems, especially to disperse particles such as carbon or carbon-coated particles in an aqueous solvent, to prepare a stable aqueous dispersion. For example, the phosphonated amines may be useful to prepare water based electrodes, especially in lithium ion batteries. In addition, the phosphonated amines of the invention improve the stability of the (aqueous) dispersion comprising the dispersant.

[0038] The phosphonated amines of the invention preferably have a molar ratio C:P of

[0039] 2.8. More preferably, the phosphonated amines of the invention have a molar ratio C:P of ^3, which provides improved stability for the dispersion comprising the dispersant.

[0040] As used herein, the term “molar ratio C:P” means the molar ratio of carbon atom and phosphorus atom in the molecule. The molar ratio C:P may be determined based on calculation of the numbers of carbon atom and phosphorus atom in the molecule, or by elemental analysis.

[0041] The phosphonated amines of the invention preferably have a molecular weight of above 600 g / mol, preferably less than 30000 g / mol, more preferably less than 4000 g / mol, even more preferably between 600-2000 g / mol.

[0042] The phosphonated amines of the invention preferably are selected from phosphonated polyetheramines, and phosphonated polyalkyleneimines; and / or wherein the phosphonated amine has a molar ratio C:P of 2==2.8, preferably ^3; and / or wherein the phosphonated amine has a molecular weight from 600 g / mol to 30000 g / mol, preferably from 600 to 4000 g / mol, more preferably between 600- 2000 g / mol.

[0043] The molecular weight may be a theoretical molecular mass. The theoretical molecular mass may be calculated based on the molecular mass of raw materials and on the assumption that the desired reaction is complete, or based on the calculation of the molecular weight of the desired theoretical product structure.

[0044] In some embodiments, the phosphonated polyetheramines are polyether polyamino methylene phosphonates, which may be represented by the following formula, or the salts thereof:

[0045] wherein n is an integer or fractional integer which is, or on average is, from about 2 to about 12, including 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 , and 12, preferably from 3 to 7, more preferably from 4 to 6, for example from 5 to 6, inclusive; and each R may be the same or different and is independently selected from hydrogen and methyl.

[0046] In some embodiments, the phosphonated polyalkyleneimine is a phosphonated branched polyethyleneimine, which may be represented by the following formula, or the salts thereof:

[0047] In some embodiments, the phosphonated polyalkyleneimine is a linear phosphonated polyethyleneimine which may be represented by the following formula, or the salts thereof:

[0048] wherein n is an integer or fractional integer which is, or on average is, from about 2 to about 12, including 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 , and 12, preferably from 3 to 7, more preferably from 4 to 6, for example from 5 to 6, inclusive.

[0049] Examples of the phosphonated amine include the following:

[0050] The phosphonated polyamine may be prepared by conventional methods, for example the method disclosed in Kurt Moedritzer and Riyad R. Irani, The Journal of Organic Chemistry 1966 31 (5), 1603-1607.

[0051] The invention further provides a dispersion comprising a continuous aqueous phase, a particulate to be dispersed and composition according to the invention.

[0052] The continuous aqueous phase comprises water as solvent. In some embodiments, the continuous aqueous phase is a water solution. The particulate to be dispersed is typically water-insoluble, which is preferably selected from particulate battery active materials, carbon or carbon-coated particles.

[0053] The carbon particles and carbon-coated particles may be selected from those conventional in the art. For example, the carbon particles may be selected from non-graphitizing carbon, graphite-based carbon; conductive carbon, carbon nano tubes. The carbon-coated particles may be selected from but not limited to carbon- coated lithium iron phosphate, carbon-coated lithium manganese iron phosphate, silicon-carbon, carbon-coated silicon-carbide, carbon-coated sodium, carbon- coated zinc, carbon-coated alumina, carbon-coated manganese, carbon-coated potassium.

[0054] The dispersion may optionally further comprise an additional additive selected from one or more of binders, adhesion promoters, wetting agents, and corrosion inhibitors.

[0055] The invention further provides an electrochemical device comprising the composition or the dispersion according to the invention.

[0056] The electrochemical device encompasses all kinds of devices that undergo electrochemical reactions. Examples of the electrochemical device include all kinds of primary batteries, secondary batteries, fuel cells, solar cells, capacitors and the like, preferably secondary batteries.

[0057] Generally, the secondary battery is fabricated by inclusion of the electrolyte in an electrode assembly composed of a cathode and an anode, which are faced opposite to each other with (or without for solid electrolyte) a separator therebetween.

[0058] The secondary batteries are preferably lithium ion batteries.

[0059] The invention further provides use of the composition according to the invention to disperse a particulate, especially a particulate selected from particulate battery active materials, carbon or carbon-coated particles in an aqueous solvent, in particular to prepare a stable aqueous dispersion.

[0060] The invention further provides use of the composition according to the invention in production of an additive which is a dispersing agent to disperse a battery active material in an aqueous solvent. The battery active materials include carbon and carbon-coated particles.

[0061] The invention further provides use of the composition according to the invention to prepare the electrode of batteries including lithium-ion batteries.

[0062] Amine

[0063] The amines that may be phosphonated to prepare the phosphonated amine of the invention include polyamines, include polyetheramines with primary amino group, polyalkyleneimines with primary amino group including branched polyalkyleneimines with primary amino group and linear polyalkyleneimines with primary amino group.

[0064] Polyetheramines with primary amino group:

[0065] The polyetheramines with primary amino group include polyoxyethylenediamines, and polyoxypropylenediamines.

[0066] In some embodiments, the polyetheramines with primary amino group are polyetheramines with two primary amine groups, wherein the amine groups are located on secondary carbon atoms at the ends of an aliphatic polyether chain.

[0067] Examples of the polyetheramines with primary amino group include JEFFAMINE® D-400 polyoxypropylenediamine (CAS 9046-10-0, commercially available from Huntsman Corporation).

[0068] JEFFAMINE® D-400 is a difunctional primary amine having an average molecular weight of approximately 400 g / mol. Its amine groups are located on secondary carbon atoms at the ends of an aliphatic polyether chain. JEFFAMINE® D-400 may be represented by the following formula:

[0069] Polyalkyleneimines with primary amino group:

[0070] The polyalkyleneimines with primary amino particularly include polyethyleneimines with primary amino group, which include branched or linear polyethyleneimines with primary amino group.

[0071] In some embodiments, the polyalkyleneimines further contain secondary amine groups. In some embodiments, the polyalkyleneimines further contain tertiary amine groups.

[0072] The polyethyleneimines with primary amino group include branched polyethyleneimines. Example of such branched polyethyleneimine includes polyethyleneimine, branched, M.W. 1 ,800, 99%, Thermo Scientific Chemicals (CAS No.: 9002-98-6, catalogue number 040528.36, commercially available from Thermo Fisher Scientific Inc.)

[0073] Battery active material

[0074] The battery active material that may be dispersed according to the invention comprise electrode active materials and conductive materials. The electrode active materials may be selected from cathode active materials and anode active materials. Particularly, the battery active material is selected from conductive materials and anode active materials, especially carbon and / or carbon-coated particles.

[0075] Examples of the cathode active materials that can be used in the present invention may include, but are not limited to, layered compounds such as lithium cobalt oxide (LiCoO2) and lithium nickel oxide (LiNiC>2), or compounds substituted with one or more transition metals; lithium manganese oxides such as compounds of Formula Lii+xMn2-xO4 (0^x^0.33), LiMnCh, LiM^Ch and LiMnO2; lithium copper oxide (I 2CUO2); vanadium oxides such as LiVsOs, N^Os and CU2V2O7; Ni-site type lithium nickel oxides of Formula LiNii-xMxO2 (M=Co, Mn, Al, Cu, Fe, Mg, B or Ga, and 0.01 ^x^O.3); lithium manganese composite oxides of Formula LiMn2-xMxO2 (M=Co, Ni, Fe, Cr, Zn or Ta, and 0.01 ^x^0.1), or Formula Li2Mn3MOs (M=Fe, Co, Ni, Cu or Zn); LiMn2O4 wherein a portion of Li is substituted with alkaline earth metal ions; disulfide compounds; and Fe2(MoO4)3, LiFesC , etc.

[0076] The conductive material is typically added in an amount of 1 to 50% by weight, based on the total weight of the mixture including the cathode active material. There is no particular limit to the conductive material, so long as it has suitable conductivity without causing chemical changes in the fabricated battery. Examples of conductive materials may include conductive materials including graphite such as natural or artificial graphite; carbon blacks such as carbon black, acetylene black, Ketjen black, channel black, furnace black, lamp black and thermal black; conductive fibers such as carbon fibers and metallic fibers; metallic powders such as carbon fluoride powder, aluminum powder and nickel powder; conductive whiskers such as zinc oxide and potassium titanate; conductive metal oxides such as titanium oxide; and polyphenylene derivatives.

[0077] Examples of the anode active materials utilizable in the present invention include carbon such as non-graphitizing carbon and graphite-based carbon; metal composite oxides such as LixFe2O3 (0^x^1), LixWO2(0^x^1) and SnxMei-xMe'yOz (Me: Mn, Fe, Pb or Ge; Me': Al, B, P, Si, Group I, Group II and Group III elements of the Periodic Table of the Elements, or halogens; 0^x^1 ; 1 ^y^3; and 1 ^z^8); lithium metals; lithium alloys; silicon-based alloys; tin-based alloys; metal oxides such as SnO, SnO2, PbO, PbO2, Pb2O3, Pb3O4, Sb2O3, Sb2O4, Sb20s, GeO, GeO2, Bi20s, Bi2O4, and Bi20s; conductive polymers such as polyacetylene; and Li-Co-Ni based materials.

[0078] The binder Is a component assisting in binding between the active material and conductive material, and in binding with the current collector. The binder is typically added in an amount of 1 to 50% by weight, based on the total weight of the mixture including the cathode active material. Examples of the binder may include polyvinylidene fluoride, polyvinyl alcohols, carboxymethylcellulose (CMC), starch, hydroxypropylcellulose, regenerated cellulose, polyvinyl pyrollidone, tetrafluoroethylene, polyethylene, polypropylene, ethylene-propylene-diene terpolymer (EPDM), sulfonated EPDM, styrene butadiene rubber (SBR), fluoro rubber and various copolymers.

[0079] The cathode is, for example, fabricated by applying a mixture of a cathode active material, a conductive material and a binder to a cathode current collector, followed by drying and pressing. If necessary, a filler may be further added to the above mixture.

[0080] The anode is, for example, fabricated by applying an anode active material to the anode current collector, followed by drying. If necessary, other components as described above may be further included.

[0081] Therefore, the present invention provides a phosphonated polyamine-based additive which acts as a dispersing agent for carbon and / or carbon-coated particles to be used for the fabrication of water based electrodes for LIB. The use of such additives increases the dispersibility of carbon and / or carbon-coated particles in water, allowing the production of more homogeneous slurries with an overall lower viscosity. A lower viscosity provides advantages also in terms of processing as it requires less solvent, energy and time since the electrode needs to be dried after coating on the current collector. The phosphonated polyamine-based additive is capable to disperse carbon and / or carbon-coated particles which can be formulated in a stable aqueous dispersion. The improved dispersion of the carbon and / or carbon-coated particles is proven by a decrease of the overall slurry viscosity. No detrimental effects in terms of coating and electrochemical stability are brought by the additive presence in the slurry composition.

[0082] The advantages brought by the phosphonated amine of the invention include but not are limited to:

[0083] - Improved dispersion of carbon and / or carbon-coated particles,

[0084] - Increased solid content of the water-based suspension (slurry),

[0085] - The prepared water-based suspension (slurry) is sable, and

[0086] - Reduced processing time and energy consumption to produce water-based electrodes.

[0087] Other advantages of the present invention would be apparent for a person skilled in the art upon reading the specification.

[0088] Brief Description of Drawings

[0089] Figure 1 shows the31P NMR spectra of the phosphonated polyamine prepared in Example 1. Figure 1 (b) is a partially enlarged version of Figure 1 (a) between 0-25 ppm.

[0090] Figure 2 shows the31P NMR spectra of the polyethyleneimine phosphonate prepared in Example 2. Figure 2 (b) is a partially enlarged version of Figure 2 (a) between 0-25 ppm.

[0091] Detailed description of the invention

[0092] The invention is now described in detail by the following examples. The scope of the invention should not be limited to the embodiments of the examples.

[0093] Materials

[0094] In the examples, the following materials were used:

[0095] Graphite: SGL Sigracel 138, commercially available from SGL Carbon;

[0096] Carbon black: Timcal Super C45, commercially available from Nanografi Nano Technology;

[0097] CMC-solution 2%: a 2 wt.% solution of carboxymethyl cellulose (CMC) in water commercially available from MTI Corporation, type code: EQ-Lib-CMC;

[0098] SBR-solution 40%: a 40 wt.% styrene butadiene rubber (SBR) aqueous solution commercially available from Nanografi Nano Technology, product number: NG08BE0308.

[0099] Procedures Slurry production was performed using a Hauschild Speed Mixer DAC 250SP equipped with disposable plastic vessel (90 mL, 51 mm diameter).

[0100] Water, binder (CMC) and 5 Zircon beads (5,0mm 95% ZrC>2) were initially mixed together with the additives and stirred for 1 minutes at 1000 rpm. Carbon black was then added to the solution, pre-mixed for 1 minute at 1000 rpm and stirred for additional 5 minutes at 1800 rpm. After a stable suspension was obtained, graphite was added to the vessel and pre-mixed for 1 minute at 1000 rpm and stirred for additional 5 minutes at 1800 rpm. Once dispersed, the second binder (SBR) was added to the slurry, followed by a last mixing step for 1 minutes at 1000 rpm.

[0101] Viscosity measurement

[0102] The measurement of the viscosity was performed on an MCR 102e (Modular Compact Rheometer) (commercially available from Anton Paar) using a plate-plate measuring system (0=80 mm, disposable), D-PP 25 (disposable-parallel plate, 0=25 mm, length=100 mm). The rheometer was equipped with a Corio CP-200F thermostat (commercially available from JULABO GmbH) and a trim spatula.

[0103] Slurry coating

[0104] Coating of slurries on coater collectors were performed using a Mini Tape Casting Coater MSK-AFA -HC 100 by MTI Corporation. Place copper foil about 12 *18mm so that all openings of the vacuum plate were covered. Place the squeegee according to the desired layer thickness and fill with slurry. The feed speed of the doctor blade was set to 20 cm / min. The coated film was dried for 30min at 120 °C in the circulating air drying cabinet.

[0105] Stability measurement

[0106] The stability of the dispersion was determined according to the following protocol: Prepare the dispersion or slurry which is homogeneous without separation of precipitation, having a solid content of 50 wt.%. Place the dispersion or slurry still at room temperature in a closed container, protected from vibrations and external factor which may influence the outcome of the test. At defined time intervals (e.g. 1 hour, 24 hours after preparation), open the container and visually inspect the dispersion or slurry to determine its stability. If the dispersion still appears homogenous, without phase separation or formation of precipitate at the bottom of the container, it can be deemed as stable. If a separation of phases or sediments are visible in the dispersion or slurry, it cannot be defined as stable.

[0107] Example 1

[0108] Synthesis

[0109] The reaction vessel was a 5-neck glass flask equipped with a stirrer, a vacuum pump, a heating and cooling unit, a reflux cooler or distillation device including a distillate template. 337.2 g of JEFFAMINE® D-400 (a polypropylene glycol terminated with primary amino groups), was placed at room temperature and inerted with nitrogen. 172.4 g of water and 112.7 g of HCI (30wt.% in water) were added with stirring in 15 min. The mixture was heated to 60 °C by heat tinting and tempering.

[0110] 276.5 g of phosphorous acid (H3PO3, solid at room temperature) was added in portions at 60-70 °C within 15 min while stirring. The reaction mixture was then heated to 100 °C. 101.3 g of paraformaldehyde was added in portions at 100 °C reaction temperature within 3 h with stirring. Subsequently, the mixture was stirred at 100 °C for 2 hours. The reaction mixture turned brownish. In 1 h, water, HCI and possibly residues of formaldehyde were distilled off at 100 °C. The pressure was gradually lowered to <20 mbar by means of a vacuum pump. The vacuum distillation was continued for 30 min at 100 °C and <20 mbar. The result was a highly viscous brownish product.

[0111] This brownish product was diluted at 80 °C with 200 g of water. The result was a homogeneous aqueous acidic solution with a pH value of about 0.5 (pH electrode). For neutralization, the acidic solution was added with stirring at 70-80 °C 500 ml of sodium hydroxide solution (20 wt.%) and 250 ml of sodium hydroxide solution (10 wt.%). A brownish homogeneous solution of polyetheramine phosphonate having a pH of 4.2, a density of 1.22 g / ml (25 °C) and a viscosity of 43 mPas (Hdppler, 25 °C) was obtained.

[0112] The obtained polyetheramine phosphonate was a mixture. The main component of the mixture was polyether polyamino methylene phosphonate (PAPEMP). The main component and the representative structure of the mixture may be represented by the following chemical structure:

[0113] The structure of the phosphonated polyamine, especially the key structure of -P- CH2-N- was confirmed mainly by31P NMR spectra as shown in Figure 1. The phosphonated amines were characterized by a series of peaks mainly in the range of 2-25 ppm.

[0114] Slurry preparation

[0115] A 2 wt.% solution of CMC in water was added to a vessel, followed by carbon black and the additive JEFFAMINE® D-400 phosphonate prepared above. After obtaining a homogenous suspension, graphite was added to the vessel, followed by additional water as solvent. In the last step, a 40% SBR aqueous solution was added. The slurry composition followed the general recipe below.

[0116] One hour after production, the slurry viscosity was measured. The maximum viscosity of the slurry was maintained below 17 Pa s.

[0117] 24 hours after production, the slurry was still homogeneous without separation of precipitation.

[0118] Example 2

[0119] Synthesis

[0120] The reaction vessel was a 5-neck glass flask equipped with stirrer, vacuum pump, heating and cooling unit, and a reflux cooler. 76.6 g of branched polyethyleneimine (commercially available from Thermo Fischer Scientific, catalogue number 040528.36) with the average molecular weight (Mn) 1800 g I mol was presented at room temperature and inerted with nitrogen. 193.2 g of HCI (37wt.% in water) was then added with stirring and cooling in 1 h. By heat tinting and tempering, the mixture was heated to 75 °C.

[0121] 146.0 g of phosphorous acid (solid at room temperature) was added in portions at 75 °C within 15 min while stirring. Subsequently, 58.8 g of paraformaldehyde was added in portions at 75-80 °C within 20 min while stirring. Subsequently, the solution was stirred at 100 °C for 4 h. The reaction mixture turned brownish. In 1.5 h at 100 °C and 800 mbar water, HCI and possibly residues of formaldehyde was distilled off. After 125 g of distillate, the distillation was interrupted. The reaction mixture was then added 125 g of water. The distillation was continued at 100 °C and 400 mbar until a distillate amount of 179 g was reached. The result was a highly viscous brownish product. This was diluted at 80 °C with 100 g of water. The resulting aqueous acidic solution was drained from the reaction vessel.

[0122] 281.4 g of this solution was returned to the reaction vessel, heated to 80 °C and diluted with 400 g of water. An inhomogeneous two-phase mixture with a pH of 0.02 (pH electrode) was formed. For neutralization, while stirring and cooling at 50- 60 °C, 123 g of sodium hydroxide solution (45 wt.%) was added. The mixture was diluted with water to a solids content of 30 wt.% and drained. A brownish homogeneous solution of polyethyleneimine phosphonate with a pH of 2.4, a density of 1.15 g / ml (25 °C) and a viscosity of 5 mPas (Hdppler, 25 °C) was obtained.

[0123] The obtained polyethyleneimine phosphonate was a mixture. The main component and the representative structure of the mixture may be represented by the following chemical structure:

[0124] The structure of the polyethyleneimine phosphonate, especially the key structure of -P-CH2-N- was confirmed mainly by31P NMR spectra as shown in Figure 2. The phosphonated amines were characterized by a series of peaks mainly in the range of 2-25 ppm.

[0125] Slurry preparation

[0126] A 2% solution of CMC in water was added to the vessel, followed by carbon black and polyethyleneimine phosphonate. After obtaining a homogenous suspension, graphite was added to the vessel, followed by additional water as solvent. In the last step, a 40% SBR aqueous solution was added. The slurry composition followed the general recipe below.

[0127] One hour after production, the slurry viscosity was measured. The maximum viscosity of the slurry was maintained below 24 Pa s.

[0128] 24 hours after production, the slurry was still homogeneous without separation of precipitation.

[0129] Example 3

[0130] Commercial product CUBLEN PEP 56 was used as the additive. A sample of Cublen PEP 56 was provided by Zschimmer & Schwarz Mohsdorf GmbH & Co. KG, Chemnitztalstrafte 1 , 09217 Burgstadt, Germany.

[0131] The product has the following chemical structure:

[0132] Slurry preparation

[0133] A 2% solution of CMC in water was added to the vessel, followed by carbon black and the additive Cublen PEP 56. After obtaining a homogenous suspension, graphite was added to the vessel, followed by additional water as solvent. In the last step, a 40% SBR aqueous solution was added. The slurry composition followed the general recipe below.

[0134] One hour after production, the slurry viscosity was measured. The maximum viscosity of the slurry was maintained below 17 Pa s.

[0135] 24 hours after production, the slurry was still homogeneous without separation or precipitation.

[0136] Comparative Example 1 (reference without additives)

[0137] A 2% solution of CMC in water was added to the vessel, followed by carbon black. After obtaining a homogenous suspension, graphite was added to the vessel, followed by additional water as solvent. In the last step, a 40% SBR aqueous solution was added. The slurry composition followed the general recipe below.

[0138] One hour after production, the slurry viscosity was measured. The maximum viscosity of the slurry was maintained below 40 Pa s.

[0139] 24 hours after production, the slurry was still homogeneous without separation or precipitation.

[0140] Comparative Example 2 (R50)

[0141] Commercial product Cublen R50 was used as additive. A sample of Cublen R50 was provided by Zschimmer & Schwarz Mohsdorf GmbH & Co. KG, Chemnitztalstrafte 1 , 09217 Burgstadt, Germany.

[0142] The product has the following chemical structure:

[0143] Slurry preparation

[0144] A 2% solution of CMC in water was added to the vessel, followed by carbon black and Cublen R50. After obtaining a homogenous suspension, graphite was added to the vessel, followed by additional water as solvent. In the last step, a 40% SBR aqueous solution was added. The slurry composition followed the general recipe below.

[0145] One hour after production, the slurry viscosity was measured. The maximum viscosity of the slurry was maintained below 8 Pa s.

[0146] 24 hours after production, the slurry was not homogeneous showing a layer of precipitated material at the bottom of its container. 1

[0147] Comparative Example 3 (AP5)

[0148] Commercial product CUBLEN AP5 was used as additive. A sample of Cublen AP5 was provided by Zschimmer & Schwarz Mohsdorf GmbH & Co. KG, Chemnitztalstrafte 1 , 09217 Burgstadt, Germany.

[0149] The product has the following chemical structure:

[0150] Slurry preparation

[0151] A 2% solution of CMC in water was added to the vessel, followed by carbon black and CUBLEN AP5. After obtaining a homogenous suspension, graphite was added to the vessel, followed by additional water as solvent. In the last step, a 40% SBR aqueous solution was added. The slurry composition followed the general recipe below.

[0152] One hour after production, the slurry viscosity was measured. The maximum viscosity of the slurry was maintained below 13 Pa s.

[0153] 24 hours after production, the slurry was not homogeneous showing a water film on the surface of the slurry.

[0154] Comparative Example 4 (E3115)

[0155] Commercial product CUBLEN E3115 was used as additive. A sample of Cublen E3115 was provided by Zschimmer & Schwarz Mohsdorf GmbH & Co. KG, Chemnitztalstrafte 1 , 09217 Burgstadt, Germany.

[0156] The product has the following chemical structure:

[0157] Slurry preparation

[0158] A 2% solution of CMC in water was added to the vessel, followed by carbon black and CUBLEN E3115. After obtaining a homogenous suspension, graphite was added to the vessel, followed by additional water as solvent. In the last step, a 40% SBR aqueous solution was added. The slurry composition followed the general recipe below.

[0159] One hour after production, the slurry viscosity was measured. The maximum viscosity of the slurry was maintained below 38 Pa s. The viscosity reduction effect was too weak.

[0160] 24 hours after production, the slurry was still homogeneous without separation or precipitation.

[0161] Comparative Example 5 (F3016)

[0162] Commercial product CUBLEN F3016 was used as additive. A sample of Cublen F3016 was provided by Zschimmer & Schwarz Mohsdorf GmbH & Co. KG, Chemnitztalstrafte 1 , 09217 Burgstadt, Germany.

[0163] The product has the following chemical structure:

[0164] Slurry preparation

[0165] A 2% solution of CMC in water was added to the vessel, followed by carbon black and CUBLEN F3016. After obtaining a homogenous suspension, graphite was added to the vessel, followed by additional water as solvent. In the last step, a 40% SBR aqueous solution was added. The slurry composition followed the general recipe below.

[0166] One hour after production, the slurry viscosity was measured. The maximum viscosity of the slurry was maintained below 6 Pa s.

[0167] 24 hours after production, the slurry was not homogeneous showing precipitate at the bottom of the container and a water film on the slurry surface.

[0168] Comparative Example 6 (D5113)

[0169] Commercial product CUBLEN D5113 was used as additive. A sample of Cublen D5113 was provided by Zschimmer & Schwarz Mohsdorf GmbH & Co. KG, Chemnitztalstrafte 1 , 09217 Burgstadt, Germany.

[0170] The product has the following chemical structure:

[0171] Slurry preparation

[0172] A 2% solution of CMC in water was added to the vessel, followed by carbon black and CUBLEN D5113. After obtaining a homogenous suspension, graphite was added to the vessel, followed by additional water as solvent. In the last step, a 40% SBR aqueous solution was added. The slurry composition followed the general recipe below.

[0173] One hour after production, the slurry viscosity was measured. The maximum viscosity of the slurry was maintained below 21 Pa s.

[0174] 24 hours after production, the slurry was not homogeneous showing precipitate at the bottom of the container.

[0175] Comparative Example 7

[0176] Synthesis

[0177] The reaction vessel was a 5-neck glass flask equipped with stirrer, vacuum pump, heating and cooling unit, and a reflux cooler. 105.1 g of diethanolamine was presented at room temperature and inerted with nitrogen. 108.5 g HCI (37wt.% in water) was then added with stirring in 40 min. The mixture was heated to 85 °C by heat tinting and tempering.

[0178] 82.0 g of phosphonic acid (solid at room temperature) was added in portions at 55- 60 °C within 15 min while stirring. 33.0 g of paraformaldehyde was added in portions at 85 °C reaction temperature within 20 min while stirring. Subsequently, 4 h at 100 °C was stirred. The reaction mixture turned brownish. In 1 h water, HCI and possibly residues of formaldehyde were distilled off at 100 °C. The pressure was gradually lowered to 50 mbar by means of a vacuum pump. The vacuum distillation was continued for 30 min at 100 °C and 50 mbar. The result was a brownish product.

[0179] This was diluted at 80 °C with 276 g of water. It was obtained homogeneous aqueous acidic solution of diethanolaminephosphonic acid having a pH of about 1 (pH electrode) and a solid content of about 30 wt.%.

[0180] The obtained diethanolaminephosphonic acid has the following chemical structure:

[0181] Slurry preparation

[0182] A 2% solution of CMC in water was added to the vessel, followed by carbon black and diethanolaminephosphonic acid. After obtaining a homogenous suspension, graphite was added to the vessel, followed by additional water as solvent. In the last step, a 40% SBR aqueous solution was added. The slurry composition followed the general recipe below.

[0183] One hour after production, the slurry viscosity was measured. The maximum viscosity of the slurry was maintained below 11 Pa s.

[0184] 24 hours after production, the slurry was not homogeneous showing a layer of precipitated material at the bottom of its container. The performance of the dispersing agents is summarized in Table 1 below:

[0185] Table 1 As shown in Table 1 , each of the inventive dispersing agents could disperse the carbon black particles in water with reduced viscosity, and could also prepare an aqueous dispersion that was stable. By contrast, the dispersing agents of the comparative examples did not have the viscosity reduction effect, or could not afford an aqueous dispersion that was stable.

[0186] As used herein, terms such as “comprise(s)” and the like as used herein are open terms meaning “including at least” unless otherwise specifically noted.

[0187] All references, tests, standards, documents, publications, etc. mentioned herein are incorporated herein by reference. Where a numerical limit or range is stated, the endpoints are included. Also, all values and subranges within a numerical limit or range are specifically included as if explicitly written out.

[0188] The above description is presented to enable a person skilled in the art to make and use the invention and is provided in the context of a particular application and its requirements. Various modifications to the preferred embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments and applications without departing from the spirit and scope of the invention. Thus, this invention is not intended to be limited to the embodiments shown but is to be accorded the widest scope consistent with the principles and features disclosed herein. In this regard, certain embodiments within the invention may not show every benefit of the invention, considered broadly.

Claims

Claims1 . A composition, especially a dispersant composition, comprising: a phosphonated polyamine; wherein the phosphonated polyamine has a molar ratio C:P of^2.8.

2. The composition of claim 1 , wherein the phosphonated polyamine is selected from phosphonated polyetheramines, and phosphonated polyalkyleneimines; and / or wherein the phosphonated polyamine has a molar ratio C:P of ^3; and / or wherein the phosphonated polyamine has a molecular weight from 600 g / mol to 30000 g / mol.

3. The composition of claim 2, wherein the phosphonated polyamine has 3 to 60 - P-CH2-N- structures.

4. The composition of claim 1 or 2, wherein the phosphonated polyamine is a compound represented by any one of the general structure formulas below, or the salts thereof:wherein residue A each independently represents either a hydrogen atom, an alkyl group with 1-4 carbon atoms, or -CH2-P(=O)(OH)2; n represents a number from 2 to 100, preferably 5 to 70, for example 3, 4, 5, 6, 7, 8, 9, 10, 11 , 12, 13, 14, 15, 16, 17, 18, 19, 20; especially 5;R represents hydrogen, methyl, ethyl, or n-propyl; preferably methyl; m represents a number from 1 to 7, preferably 1 to 5, for example, 1 , 2, 3, 4, or 5, especially 5; o represents a number from 1 to 20, preferably from 1 to 10, most preferably from 1 to 6, for example, 1 , 2, 3, 4, or 5; especially 1 ; with the proviso that on average the polyamines contain at least two -CH2- P(=O)(OH)2 groups per molecule.

5. The composition of claim 2, wherein the phosphonated polyalkyleneimine is a compound represented by the formula XpAp+2, or the salts thereof, whereinX representsp represents a number2, preferably ^3;A represents H, alkyl with 1 to 4 carbon atoms, or -CH2P(=O)(OH)2; wherein the dotted lines denote either a single bond to a unit A or a C-N single bond to a unit X; with the proviso that on an average at least two -CH2-P(=O)(OH)2 groups are contained per molecule.

6. The dispersant of claim 2, wherein the phosphonated polyalkyleneimine is a compound comprising or consisting of units X and units A, or the salts thereof, whereinX represents; the number of unit X is at least 2, preferably at least 3;A represents H, alkyl with 1 to 4 carbon atoms, or -CH2P(=O)(OH)2; wherein the dotted lines denote either a single bond to a unit A or a C-N single bond to a unit X, and wherein each X and each A has at least one single bond to a unit X; with the proviso that on an average at least two -CH2-P(=O)(OH)2 groups are contained per molecule; preferably, the branched or linear phosphonated polyethyleneimine contains an average at least three X per molecule.

7. The dispersant of claim 2, wherein the phosphonated polyalkyleneimine is a phosphonated linear polyethyleneimine represented by the formula below, or the salts thereof,whereinA represents H, alkyl with 1 to 4 carbon atoms, or -CH2P(=O)(OH)2; q represents a number2, preferably ^3; each repeat unit X, i.e. the part in the brackets, has at least one C-N single bond to another unit X; the two terminal X units have one C-N-single bond to the X neighbour; and the remaining units X have two C-N single bonds to both X neighbours.

8. The composition of claim 2, wherein the phosphonated polyetheramine is a polyether polyamino methylene phosphonate, which is represented by the following formula, or the salts thereof:wherein n is an integer or fractional integer which is, or on average is, from about 2 to about 12, preferably from 3 to 7, more preferably from 4 to 6, for example from 5 to 6, inclusive; and each R is the same or different and is independently selected from hydrogen and methyl.

9. The composition of claim 2, wherein the phosphonated polyalkyleneimine is phosphonated branched polyethyleneimine, which is represented by the following formula, or the salts thereof:

10. The composition of claim 2, wherein the phosphonated polyalkyleneimine is phosphonated linear polyethyleneimine which is represented by the following formula, or the salts thereof:wherein n is an integer or fractional integer which is, or on average is, from about 2 to about 12, preferably from 3 to 7, more preferably from 4 to 6, for example from 5 to 6, inclusive.

11. A dispersion comprising a continuous aqueous phase, a particulate to be dispersed and the composition according to any one of claims 1-10.

12. The dispersion of claim 11 , wherein the dispersion is stable.

13. The dispersion of claim 11 , wherein the particulate to be dispersed is selected from particulate battery active materials, carbon or carbon-coated particles.

14. An electrochemical device comprising the composition according to any one of claims 1 -10 or the dispersion according to any one of claims 11-13.

15. Use of the composition according to any one of claims 1 -10 as a dispersant.

16. The use of claim 15, wherein the composition is useful to disperse particles such as carbon or carbon-coated particles in an aqueous solvent, especially to prepare a stable aqueous dispersion.

17. Use of the composition according to any one of claims 1-10 to disperse a particulate, especially a particulate selected from particulate battery active materials, carbon or carbon-coated particles in an aqueous solvent, in particular to prepare a stable aqueous dispersion.

18. Use of the composition according to any one of claims 1-10 in production of an additive which is a dispersing agent to disperse a battery active material in an aqueous solvent.

19. Use of the composition according to any one of claims 1-10 to prepare the electrode of batteries including lithium-ion batteries.

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