Electrode binder slurry composition for lithium ion electricity storage device

Abstract

The present invention provides a slurry composition comprising: a binder comprising a polymer dispersed in a liquid medium, the polymer comprising a fluoropolymer; an adhesion promoter; and at least one of an electrochemically active material or a conductive agent. The invention also provides an electrode and an electricity storage device.

Description

[0001] This application is a divisional application of the Chinese patent application with application number 201880045410.4. Field of the Invention

[0002] The present invention relates to a fluoropolymer, such as polyvinylidene fluoride (PVDF), slurry composition for making electrodes for power storage devices, such as batteries. Background of the Invention

[0004] There is a trend in the electronics industry to produce smaller devices powered by smaller and lighter batteries. Batteries with a negative electrode, such as a carbonaceous material, and a positive electrode, such as a lithium metal oxide, can provide relatively high power and low weight.

[0005] Polyvinylidene fluoride, due to its excellent electrochemical resistance, has been found to be a useful binder for forming electrodes for use in electrical storage devices. Typically, polyvinylidene fluoride is dissolved in an organic solvent, and the electrode material (i.e., an electrochemically active compound and typically a conductive material such as a carbonaceous material) is combined with the PVDF solution to form a slurry that is applied to a metal foil or mesh to form an electrode.

[0006] The role of organic solvent is to dissolve PVDF so as to provide good adhesion between electrode material particles and metal foil or net when evaporating organic solvent. At present, the organic solvent of choice is N-methyl-2-pyrrolidone (NMP). The PVDF binder dissolved in NMP provides excellent adhesion and interconnectivity of all active ingredients in the electrode composition. The bonded composition can tolerate the expansion and contraction of the large volume during the charge and discharge cycle without losing the interconnectivity in the electrode. The interconnectivity of active ingredients in the electrode is extremely important in battery performance, particularly during the charge and discharge cycle, because electrons must move across the electrode, and lithium ion mobility requires the interconnectivity between particles in the electrode.

[0007] Unfortunately, NMP is a toxic material and presents health and environmental issues. It is desirable to replace NMP as a solvent for PVDF binders. However, NMP has a relatively unique ability to dissolve PVDF, which is almost insoluble in other organic solvents.

[0008] In order to effectively utilize PVDF compositions in organic solvents other than NMP in electrode formation processes, PVDF must be dispersed in the solvent. However, the dispersion must be compatible with current manufacturing practices and provide the desired properties of intermediates and final products. Some common criteria include: a) stability of the fluoropolymer dispersion with adequate shelf life, b) slurry stability after blending the electrochemically active and / or conductive powder with the dispersion, c) appropriate viscosity of the slurry to facilitate good application properties, and d) adequate inter-electrode penetration.

[0009] Water-based PVDF dispersions have also been considered, but the resulting electrode coatings often exhibit reduced peel strength compared to solvent-based types.

[0010] It is therefore an object of the present invention to provide a stable PVDF dispersion having good application properties for the preparation of an electrode-forming composition capable of producing high-quality electrodes with continuity and satisfactory peel strength for batteries and other electrical storage devices, avoiding the aforementioned disadvantages associated with the use of N-methyl-2-pyrrolidone. SUMMARY OF THE INVENTION

[0012] The present invention provides a slurry composition comprising an electrochemically active material; a binder comprising a polymer dispersed in a liquid medium, the polymer including a fluoropolymer; and an adhesion promoter.

[0013] The present invention also provides a slurry composition comprising a conductive agent; a binder comprising a polymer dispersed in a liquid medium, the polymer including a fluorine-containing polymer; and an adhesion promoter.

[0014] The present invention further provides an electrode comprising a current collector; and a film formed on the current collector, wherein the film is deposited from a slurry composition comprising: an electrochemically active material; a conductive agent; a binder comprising a polymer dispersed in a liquid medium, the polymer including a fluorine-containing polymer; and an adhesion promoter.

[0015] The present invention also provides an electricity storage device, which comprises an electrode, the electrode comprises a current collector, and a film formed on the current collector, wherein the film is deposited from a slurry composition, the slurry composition comprising: an electrochemically active material; a conductive agent; a binder comprising a polymer dispersed in a liquid medium, the polymer including a fluorine-containing polymer; and an adhesion promoter; a counter electrode; and an electrolyte. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a graph showing the first derivative of Log viscosity versus temperature, wherein the peak maximum is used to determine the dissolution temperature of PVDF dispersed in 1,2,3-triacetoxypropane (triacetin) from the abscissa. DETAILED DESCRIPTION OF THE INVENTION

[0018] The present invention relates to a slurry composition comprising an electrochemically active material; a binder comprising a polymer dispersed in a liquid medium, the polymer comprising a fluorine-containing polymer; and an adhesion promoter. The slurry composition may optionally further comprise a dispersant and / or a conductive agent.

[0019] The slurry composition contains an electrochemically active material. The material constituting the electrochemically active material contained in the slurry is not particularly limited, and a suitable material can be selected according to the type of electricity storage device of interest.

[0020] The electrochemically active material may include a material used as an active material for a positive electrode. The electrochemically active material may include a material capable of incorporating lithium (including incorporation by lithium intercalation / deintercalation), a material capable of lithium conversion, or a combination thereof. Non-limiting examples of electrochemically active materials capable of incorporating lithium include LiCoO2, LiNiO2, LiFePO4, LiCoPO4, LiMnO2, LiMn2O4, Li(NiMnCo)O2, Li(NiCoAl)O2, carbon-coated LiFePO4, and combinations thereof. Non-limiting examples of materials capable of lithium conversion include sulfur, LiO2, FeF2 and FeF3, Si, aluminum, tin, SnCo, Fe3O4, and combinations thereof.

[0021] The electrochemically active material may include a material used as an active material for a negative electrode. The electrochemically active material may include graphite, lithium titanate, a silicon compound, tin, a tin compound, sulfur, a sulfur compound, or a combination thereof.

[0022] The electrochemically active material may be present in the slurry in an amount of 45% to 95% by weight, such as 70% to 98% by weight, based on the total solids weight of the slurry.

[0023] According to the present invention, the binder comprises a polymer dispersed in a liquid medium, the polymer comprising a fluorine-containing polymer. The fluorine-containing polymer can be used as the whole or one component of the binder for the slurry composition.

[0024] Fluoropolymers may include (co)polymers containing the residue of vinylidene fluoride. The non-limiting example of (co)polymers containing the residue of vinylidene fluoride is polyvinylidene fluoride polymer (PVDF). As used herein, "polyvinylidene fluoride polymer" includes homopolymers, copolymers, such as binary copolymers, and terpolymers, including high molecular weight homopolymers, copolymers, and terpolymers. Such (co)polymers include those containing at least 50 mol %, such as at least 75 mol %, and at least 80 mol %, and at least 85 mol % of the residue of vinylidene fluoride (also referred to as vinylidene fluoride). Vinylidene fluoride monomers can be copolymerized with at least one comonomer selected from the following: tetrafluoroethylene, trifluoroethylene, chlorotrifluoroethylene, hexafluoropropylene, vinyl fluoride, pentafluoropropylene, tetrafluoropropylene, perfluoromethyl vinyl ether, perfluoropropyl vinyl ether and any other monomers that will be conveniently copolymerized with vinylidene fluoride, thereby manufacturing fluoropolymers of the present invention. The fluoropolymers may also include PVDF homopolymers.

[0025] The fluoropolymer may include a high molecular weight PVDF having a weight average molecular weight of at least 50,000 g / mol, such as at least 100,000 g / mol, and may be in the range of 50,000 g / mol to 1,500,000 g / mol, such as 100,000 g / mol to 1,000,000 g / mol. PVDF is commercially available, for example, from Arkema under the trademark KYNAR, and from Inner Mongolia 3F Wanhao Fluorochemical Co., Ltd.

[0026] The fluoropolymer may include nanoparticles. As used herein, the term "nanoparticles" refers to particles with a particle size lower than 1,000nm. The particle size that the fluoropolymer may have is at least 50nm, for example at least 100nm, for example at least 250nm, for example at least 300nm, and may be no more than 900nm, for example no more than 600nm, for example no more than 450nm, for example no more than 400nm, for example no more than 300nm, for example no more than 200nm. The particle size that the fluoropolymer nanoparticle may have is 50nm to 900nm, for example 100nm to 600nm, for example 250nm to 450nm, for example 300nm to 400nm, for example 100nm to 400nm, for example 100nm to 300nm, for example 100nm to 200nm. As used herein, the term "particle size" refers to the average diameter of the fluoropolymer particles. The particle sizes cited in this disclosure are determined by the following procedure: The sample is prepared by dispersing the fluoropolymer on a carbon ribbon strip connected to a scanning electron microscope (SEM) aluminum stub. Excess particles are blown off the carbon ribbon strip with compressed air. The sample is then sputter coated with Au / Pd for 20 seconds and then analyzed in a Quanta 250 FEG SEM (field emission gun scanning electron microscope) under high vacuum. The accelerating voltage is set to 20.00 kV and the spot size is set to 3.0. Images are collected from three different areas on the prepared sample, and the diameter of 10 fluoropolymer particles from each area is measured using ImageJ software, and a total of 30 particle size measurements are averaged together to determine the average particle size.

[0027] The fluoropolymer may be present in the binder in an amount of 40 to 100 wt %, such as 40 to 96 wt %, such as 50 to 90 wt %, based on the total weight of the binder solids.

[0028] The liquid medium of the slurry composition may include an organic medium. As used herein, the term "organic medium" refers to a liquid medium comprising less than 50% by weight water based on the total weight of the organic medium. Such an organic medium may comprise less than 40% by weight water, or less than 30% by weight water, or less than 20% by weight water, or less than 10% by weight water, or less than 5% by weight water, or less than 1% by weight water, or less than 0.1% by weight water, based on the total weight of the organic medium, or may be free of water. The organic solvent comprises more than 50% by weight of the organic medium, such as at least 70% by weight, such as at least 80% by weight, such as at least 90% by weight, such as at least 95% by weight, such as at least 99% by weight, such as at least 99.9% by weight, such as 100% by weight, based on the total weight of the organic medium. The organic solvent may comprise 50.1% to 100% by weight, such as 70% to 100% by weight, such as 80% to 100% by weight, such as 90% to 100% by weight, such as 95% to 100% by weight, such as 99% to 100% by weight, such as 99.9% to 100% by weight, based on the total weight of the organic medium.

[0029] The organic medium may comprise, consist essentially of, or consist of, for example, ketones such as methyl ethyl ketone, cyclohexanone, and isophorone, ethers such as C1-C4 alkyl ethers of ethylene glycol or propylene glycol, butyl pyrrolidone, trialkyl phosphates, 1,2,3-triacetoxypropane, 3-methoxy-N,N-dimethylpropionamide, ethyl acetoacetate, gamma-butyrolactone, propylene glycol methyl ether, propylene carbonate, dimethyl adipate, propylene glycol methyl ether acetate, dibasic acid ester (DBE), dibasic acid ester 5 (DBE-5), 4-hydroxy-4-methyl-2-pentanone (diacetone alcohol), propylene glycol diacetate, dimethyl phthalate, methyl isoamyl ketone, ethyl propionate, 1-ethoxy-2-propanol, dipropylene glycol dimethyl ether, saturated and unsaturated linear and cyclic ketones (which may be present as mixtures thereof as Eastman TM C-11 ketone commercially available from Eastman Chemical Company), diisobutyl ketone, acetate (available as Exxate TM 1000 is commercially available from Hallstar), tripropylene glycol methyl ether, diethylene glycol ethyl ether acetate, or a combination thereof. Trialkyl phosphates may include, for example, trimethyl phosphate, triethyl phosphate, tripropyl phosphate, tributyl phosphate, and the like.

[0030] As discussed above, the evaporation rate of the organic medium at the dissolution temperature of the fluoropolymer dispersed in the organic medium is less than 10 g / min m 2. The evaporation rate can be measured using ASTM D3539 (1996). According to the present invention, the dissolution temperature of a fluoropolymer dispersed in an organic medium can be determined by measuring the complex viscosity of the mixture as a function of temperature. Such a technique can be applied to fluoropolymers (in addition to other types of polymers) mixed in an organic medium, wherein the total mass of the non-volatile solid components of the mixture is 44% to 46%, for example 45%, of the total mass of the mixture. The complex viscosity can be measured using an Anton-Paar MCR301 rheometer using a 50 mm cone and a temperature-controlled plate. The complex viscosity of the fluoropolymer mixture is measured in a temperature range of 35°C to at least 75°C, with a heating rate of 10°C / min, an oscillation frequency of 1 Hz, and a stress amplitude limit of 90 Pa. The dissolution of a fluoropolymer in an organic medium is indicated by a complex viscosity that increases rapidly with increasing temperature. The dissolution temperature is defined as the temperature at which the rate of change of viscosity with increasing temperature is the highest, and is determined by determining the Log of the complex viscosity. 10 It is calculated at the temperature where the first derivative of temperature is maximum. Figure 1 To display Log 10 A graph of the first derivative of viscosity versus temperature, where the peak maximum is used to determine the dissolution temperature of the fluoropolymer polyvinylidene fluoride (PVDF T-1 from Inner Mongolia 3F Wanhao Fluorochemical Co. Ltd.) dispersed in the organic medium 1,2,3-triacetoxypropane (triacetin) from the abscissa. The following table shows the dissolution temperatures in the various solvents or solvent mixtures listed, determined according to this method using PVDF T-1 from Inner Mongolia 3F Wanhao Fluorochemical Co. Ltd. (PVDF T-1 has a particle size of about 330 to 380 nm and a weight average molecular weight of about 130,000 to 160,000 g / mol).

[0031]

[0032] 1 Propylene glycol methyl ether, commercially available from The Dow Chemical Company.

[0033] The dissolution temperature of the fluoropolymer dispersed in the organic medium may be below 77° C., such as below 70° C., such as below 65° C., such as below 60° C., such as below 55° C., such as below 50° C. The dissolution temperature of the fluoropolymer dispersed in the organic medium may be in the range of 30° C. to 77° C., such as 30° C. to 70° C., such as 30° C. to 65° C., such as 30° C. to 60° C., such as 30° C. to 55° C., such as 30° C. to 50° C. The dissolution temperature may be measured according to the method discussed above.

[0034] The organic medium may include, for example, butyl pyrrolidone, trialkyl phosphate, 1,2,3-triacetoxypropane, 3-methoxy-N,N-dimethylpropionamide, ethyl acetoacetate, gamma-butyrolactone, propylene glycol methyl ether, cyclohexanone, propylene carbonate, dimethyl adipate, propylene glycol methyl ether acetate, dibasic acid ester (DBE), dibasic acid ester 5 (DBE-5), 4-hydroxy-4-methyl-2-pentanone (diacetone alcohol), propylene glycol diacetate, dimethyl phthalate, methyl isoamyl ketone, ethyl propionate, 1-ethoxy-2-propanol, dipropylene glycol dimethyl ether, saturated and unsaturated linear and cyclic ketones (which may be used as mixtures thereof as Eastman TM C-11 ketone commercially available from Eastman Chemical Company), diisobutyl ketone, acetate (available as Exxate TM 1000 is commercially available from Hallstar), tripropylene glycol methyl ether, diethylene glycol ethyl ether acetate, or a combination thereof. Trialkyl phosphates may include, for example, trimethyl phosphate, triethyl phosphate, tripropyl phosphate, tributyl phosphate, and the like.

[0035] The organic medium may consist essentially of or consist of, for example, butyl pyrrolidone, trialkyl phosphate, 1,2,3-triacetoxypropane, 3-methoxy-N,N-dimethylpropionamide, ethyl acetoacetate, gamma-butyrolactone, cyclohexanone, propylene carbonate, dimethyl adipate, propylene glycol methyl ether acetate, dibasic acid ester (DBE), dibasic acid ester 5 (DBE-5), 4-hydroxy-4-methyl-2-propanone (diacetone alcohol), propylene glycol diacetate, dimethyl phthalate, methyl isoamyl ketone, ethyl propionate, 1-ethoxy-2-propanol, saturated and unsaturated linear and cyclic ketones (which may be present as mixtures thereof as Eastman TM C-11 ketone commercially available from Eastman Chemical Company), diisobutyl ketone, acetate (available as Exxate TM 1000 commercially available from Hallstar), diethylene glycol ethyl ether acetate, or a combination thereof.

[0036] The organic medium may include a main solvent and a co-solvent that form a uniform continuous phase with the fluoropolymer as a dispersed phase. The main solvent and co-solvent and their relative amounts may be selected to provide a dispersion of the fluoropolymer in the organic medium at room temperature, i.e., about 23° C. The main solvent and the co-solvent may both include an organic solvent. If used alone, the fluoropolymer may be dissolved in the main solvent at room temperature, but the use of a co-solvent with the main solvent may allow the fluoropolymer to be stably dispersed in the organic medium. The main solvent may include, consist essentially of, or consist of, for example, butyl pyrrolidone, trialkyl phosphate, 3-methoxy-N,N-dimethylpropionamide, 1,2,3-triacetoxypropane, or a combination thereof. The co-solvent may include, consist essentially of, or consist of, for example, ethyl acetoacetate, γ-butyrolactone, and / or glycol ethers such as propylene glycol methyl ether, dipropylene glycol methyl ether, propylene glycol monopropyl ether, diethylene glycol monobutyl ether, ethylene glycol monohexyl ether, and the like. The main solvent may be present in an amount of at least 50% by weight, such as at least 65% by weight, such as at least 75% by weight, and may be present in an amount not exceeding 99% by weight, such as not exceeding 90% by weight, such as not exceeding 85% by weight, based on the total weight of the organic medium. The main solvent may be present in an amount of 50% to 99% by weight, such as 65% to 90% by weight, such as 75% to 85% by weight, based on the total weight of the organic medium. The co-solvent may be present in an amount of at least 1% by weight, such as at least 10% by weight, such as at least 15% by weight, and may be present in an amount not exceeding 50% by weight, such as not exceeding 35% by weight, such as not exceeding 25% by weight. The co-solvent may be present in an amount of 1% to 50% by weight, such as 10% to 35% by weight, such as 15% to 25% by weight, based on the total weight of the organic medium.

[0037] The organic medium may also have an evaporation rate of greater than 80 g / min m at 180°C. 2 , for example, greater than 90 g / min m at 180 °C 2 , for example, greater than 100 g / min m at 180°C 2 .

[0038] The liquid medium can comprise an aqueous medium. As used herein, the term "aqueous medium" refers to a liquid medium comprising at least 50 % by weight of water, based on the gross weight of this organic medium. Such an aqueous medium can comprise an organic solvent lower than 40 % by weight or lower than 30 % by weight or lower than 20 % by weight or lower than 10 % by weight or lower than 5 % by weight or lower than 1 % by weight or lower than 0.1 % by weight, based on the gross weight of this aqueous medium. Water can account for this aqueous medium more than 50 % by weight, for example at least 60 % by weight, for example at least 70 % by weight, for example at least 80 % by weight, for example at least 90 % by weight, for example at least 95 % by weight, for example at least 99 % by weight, for example at least 99.9 % by weight, for example 100 % by weight, based on the gross weight of this aqueous medium. Water may comprise 50.1% to 100% by weight, such as 70% to 100% by weight, such as 80% to 100% by weight, such as 90% to 100% by weight, such as 95% to 100% by weight, such as 99% to 100% by weight, such as 99.9% to 100% by weight, based on the total weight of the aqueous medium.

[0039] The liquid medium may be present in an amount of at least 10% by weight, such as at least 15% by weight, such as at least 20% by weight, such as at least 30% by weight, such as at least 35% by weight, such as at least 40% by weight, and may be present in an amount not exceeding 80% by weight, such as not exceeding 70% by weight, such as not exceeding 60% by weight, such as not exceeding 50% by weight, such as not exceeding 45% by weight, such as not exceeding 45% by weight, such as not exceeding 40% by weight, such as not exceeding 35% by weight, such as not exceeding 29% by weight, such as not exceeding 25% by weight, based on the total weight of the slurry composition. The liquid medium may be present in an amount of, for example, 20% to 80% by weight, 10% to 70% by weight, such as 30% to 70% by weight, such as 35% to 60% by weight, such as 40% to 50% by weight, 15% to 60% by weight, 15% to 50% by weight, 15% to 45% by weight, 15% to 40% by weight, 15% to 35% by weight, 15% to 29% by weight, 15% to 25% by weight, based on the total weight of the slurry composition.

[0040] The slurry composition may be substantially free of, substantially free of, or completely free of N-methyl-2-pyrrolidone (NMP). As used herein, the slurry composition is "substantially free of" NMP means that if NMP may be present, it is present in an amount of less than 5% by weight, based on the total weight of the slurry composition. As used herein, the slurry composition is "substantially free of" NMP means that if NMP may be present, it is present in an amount of less than 0.3% by weight, based on the total weight of the slurry composition. As used herein, the slurry composition is "completely free of" NMP means that NMP is not present in the slurry composition, i.e., 0.0% by weight, based on the total weight of the slurry composition.

[0041] The slurry composition may be substantially free, essentially free, or completely free of ketones, such as methyl ethyl ketone, cyclohexanone, isophorone, acetophenone.

[0042] The slurry composition may be substantially free, essentially free, or completely free of ethers, such as C1-C4 alkyl ethers of ethylene glycol or propylene glycol.

[0043] The slurry composition further comprises an adhesion promoter. The adhesion promoter may include a polyvinylidene fluoride copolymer different from the above-mentioned fluoropolymer, an acid-functional polyolefin or a thermoplastic material.

[0044] The polyvinylidene fluoride copolymer adhesion promoter comprises a constituent unit containing a residue of vinylidene fluoride and at least one of the following: (i) (meth) acrylic acid; and / or (ii) (meth) hydroxyalkyl acrylate. (Meth) acrylic acid may include acrylic acid, methacrylic acid, or a combination thereof. (Meth) hydroxyalkyl acrylate may include (meth) C1-C5 hydroxyalkyl esters of acrylic acid, such as (meth) hydroxyethyl acrylate, (meth) 2-hydroxypropyl acrylate, (meth) 2-hydroxybutyl acrylate, or a combination thereof. The polyvinylidene fluoride copolymer adhesion promoter comprises at least 50 mol % of constituent units containing a residue of vinylidene fluoride, such as at least 70 mol %, such as at least 80 mol % and not more than 99 mol %, such as not more than 98 mol %, such as not more than 95 mol %, based on the total molar content of the polyvinylidene fluoride copolymer adhesion promoter. The polyvinylidene fluoride copolymer adhesion promoter comprises 50% to 99% by mole of constituent units comprising the residue of vinylidene fluoride, for example 70% to 98% by mole, for example 80% to 95% by mole, based on the total molar content of the polyvinylidene fluoride copolymer adhesion promoter. The polyvinylidene fluoride copolymer adhesion promoter may comprise at least 0.01% by mole of constituent units comprising the residue of (meth) acrylic acid, for example at least 0.02% by mole, for example at least 0.03% by mole, and may comprise no more than 10% by mole, for example no more than 5% by mole, for example no more than 2% by mole, based on the total molar content of the polyvinylidene fluoride copolymer adhesion promoter. The polyvinylidene fluoride copolymer adhesion promoter may comprise 0.01% to 10% by mole of constituent units comprising the residue of (meth) acrylic acid, for example 0.02% to 5% by mole, for example 0.03% to 2% by mole, based on the total molar content of the polyvinylidene fluoride copolymer adhesion promoter. The polyvinylidene fluoride copolymer adhesion promoter may include at least 0.01 mol% of constituent units comprising the residue of (meth) hydroxyalkyl acrylate, such as at least 0.02 mol%, such as at least 0.03 mol%, and may include no more than 10 mol%, such as no more than 5 mol%, such as no more than 2 mol%, based on the total molar content of the polyvinylidene fluoride copolymer adhesion promoter. The polyvinylidene fluoride copolymer adhesion promoter may include 0.01% to 10 mol% of constituent units comprising the residue of (meth) hydroxyalkyl acrylate, such as 0.02% to 5 mol%, such as 0.03% to 2 mol%, based on the total molar content of the polyvinylidene fluoride copolymer adhesion promoter. Commercially available examples of such addition polymers include SOLEF 5130, available from Solvay. Different from the fluoropolymers discussed above, the polyvinylidene fluoride copolymer may be dispersed or dissolved in the organic medium of the slurry composition.

[0045] Acid functional polyolefin adhesion promoter comprises ethylene-(meth)acrylic acid copolymer, for example ethylene-acrylic acid copolymer or ethylene-methacrylic acid copolymer.Ethylene-acrylic acid copolymer can comprise containing following constituent unit: 10% to 50% by weight acrylic acid, for example 15% to 30% by weight, for example 17% to 25% by weight, for example about 20% by weight, based on the gross weight of the ethylene-acrylic acid copolymer, and 50% to 90% by weight ethylene, for example 70% to 85% by weight, for example 75% to 83% by weight, for example about 80% by weight, based on the gross weight of the ethylene-acrylic acid copolymer.The commercially available example of such addition polymer comprises PRIMACOR 5980i, available from Dow Chemical Company.

[0046] The adhesion promoter may be present in the slurry composition in an amount of 10% to 60% by weight, such as 20% to 60% by weight, such as 30% to 60% by weight, such as 10% to 50% by weight, such as 15% to 40% by weight, such as 20% to 30% by weight, such as 35% to 35% by weight, based on the total weight of the binder solids (including the adhesion promoter).

[0047] The slurry composition may optionally further comprise a dispersant. The dispersant may assist in dispersing the fluoropolymer, and / or the conductive agent and / or the electrochemically active material as present in the liquid medium. When present, the dispersant may be a component of the slurry composition binder. The dispersant may comprise at least one phase compatible with the other components of the fluoropolymer and / or the slurry composition, such as (if present) the conductive agent or the electrochemically active material, and may further comprise at least one phase compatible with the liquid medium. The slurry composition may comprise one, two, three, four or more different dispersants, and each dispersant may assist in dispersing the different components of the slurry composition. The dispersant may comprise any material having a phase compatible with the fluoropolymer and / or the conductive agent or the electrochemically active material as present and the liquid medium. As used herein, the term "compatible" refers to the ability of a material to form a substantially uniform blend with other materials and to maintain a substantially uniform blend over time. Fluoropolymers and dispersants may not be covalently bonded. For example, a dispersant may comprise a polymer containing such a phase. The polymer may be in the form of a block polymer, a random polymer or a gradient polymer, wherein the phases present in the different blocks of the polymer are randomly contained in the entire polymer, or gradually or more or less densely present along the polymer backbone. The dispersant may comprise any suitable polymer for this purpose. For example, the polymer may comprise an addition polymer produced by polymerizing ethylenically unsaturated monomers, a polyepoxide polymer, a polyamide polymer, a polyurethane polymer, a polyurea polymer, a polyether polymer, a polyacid polymer, and a polyester polymer, etc. The dispersant may also be used as an additional component of the binder of the slurry composition.

[0048] Dispersants may include functional groups. Functional groups may include, for example, active hydrogen functional groups, heterocyclic groups, and combinations thereof. As used herein, the term "active hydrogen functional group" refers to those groups reactive with isocyanate, as determined by the Zerewitinoff test described in JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, Vol. 49, p. 3181 (1927), and includes, for example, hydroxyl groups, primary or secondary amino groups, carboxylic acid groups, and thiol groups. As used herein, the term "heterocyclic group" refers to a cyclic group containing at least two different elements in its ring, such as having at least one atom other than carbon in the ring structure, such as oxygen, nitrogen or sulfur. Non-limiting examples of heterocyclic groups include epoxides, lactams and lactones. In addition, when epoxy functional groups are present on addition polymers, epoxy functional groups on dispersants may be post-reacted with β-hydroxy functional acids. Non-limiting examples of beta-hydroxy functional acids include citric acid, tartaric acid and / or aromatic acids such as 3-hydroxy-2-naphthoic acid.The ring opening reaction of the epoxy functional groups will generate hydroxyl functional groups on the dispersant.

[0049] When acid functional groups are present, the dispersant may have a theoretical acid equivalent weight of at least 350 g / acid equivalent, such as at least 878 g / acid equivalent, such as at least 1,757 g / acid equivalent, and may not exceed 17,570 g / acid equivalent, such as not more than 12,000 g / acid equivalent, such as not more than 7,000 g / acid equivalent. The dispersant may have a theoretical acid equivalent weight of 350 to 17,570 g / acid equivalent, such as 878 to 12,000 g / acid equivalent, such as 1,757 to 7,000 g / acid equivalent.

[0050] As mentioned above, the dispersant may include an addition polymer. The addition polymer may be derived from and contain constituent units (such as those discussed below) containing the residue of one or more α, β-ethylenically unsaturated monomers, and may be prepared by polymerizing the reaction mixture of these monomers. The monomer mixture may include one or more ethylenically unsaturated monomers containing active hydrogen groups. The reaction mixture may also include ethylenically unsaturated monomers containing heterocyclic groups. As used herein, an ethylenically unsaturated monomer containing a heterocyclic group refers to a monomer having at least one α, β ethylenically unsaturated group and having at least one atom other than carbon in the ring structure, such as at least a cyclic portion of oxygen, nitrogen or sulfur. Non-limiting examples of ethylenically unsaturated monomers containing heterocyclic groups include epoxy-functional ethylenically unsaturated monomers, vinyl pyrrolidone and vinyl caprolactam, etc. The reaction mixture may additionally include other ethylenically unsaturated monomers, such as alkyl esters of (meth) acrylic acid and other substances described below.

[0051] The addition polymer may include a (meth) acrylic polymer comprising constituent units containing residues of one or more (meth) acrylic monomers. The (meth) acrylic polymer may be prepared by polymerizing a reaction mixture of α,β-ethylenically unsaturated monomers, the mixture comprising one or more (meth) acrylic monomers and optionally other ethylenically unsaturated monomers. As used herein, the term "(meth) acrylic monomer" refers to acrylic acid, methacrylic acid, and monomers derived therefrom, including alkyl esters of acrylic acid and methacrylic acid, and the like. As used herein, the term "(meth) acrylic polymer" refers to a polymer derived from or comprising constituent units containing residues of one or more (meth) acrylic monomers. The monomer mixture may include one or more (meth) acrylic monomers containing active hydrogen groups, ethylenically unsaturated monomers containing heterocyclic groups, and other ethylenically unsaturated monomers. The (meth)acrylic polymers can also be prepared using epoxy-functional ethylenically unsaturated monomers such as glycidyl methacrylate in the reaction mixture, and the epoxy-functional groups on the resulting polymer can be post-reacted with a β-hydroxy-functional acid such as citric acid, tartaric acid and / or 3-hydroxy-2-naphthoic acid to produce hydroxy-functional groups on the (meth)acrylic polymer.

[0052] The addition polymer may include constituent units containing residues of α,β-ethylenically unsaturated carboxylic acids. Non-limiting examples of α,β-ethylenically unsaturated carboxylic acids include those containing up to 10 carbon atoms, such as acrylic acid and methacrylic acid. Non-limiting examples of other unsaturated acids are α,β-ethylenically unsaturated dicarboxylic acids, such as maleic acid or its anhydride, fumaric acid and itaconic acid. In addition, half esters of these dicarboxylic acids may also be used. The constituent units containing residues of α,β-ethylenically unsaturated carboxylic acids may account for at least 1% by weight, such as at least 2% by weight, such as at least 5% by weight, and may not exceed 50% by weight, such as not more than 20% by weight, such as not more than 10% by weight, such as not more than 5% by weight, based on the total weight of the addition polymer. The constituent units containing residues of α,β-ethylenically unsaturated carboxylic acids may account for 1% to 50% by weight, 2% to 50% by weight, such as 2% to 20% by weight, such as 2% to 10% by weight, such as 2% to 5% by weight, such as 1% to 5% by weight, based on the total weight of the addition polymer. The addition polymer may be derived from a reaction mixture comprising an α,β-ethylenically unsaturated carboxylic acid in an amount of 1% to 50%, 2% to 50%, such as 2% to 20%, such as 2% to 10%, such as 2% to 5%, such as 1% to 5% by weight, based on the total weight of the polymerizable monomers used in the reaction mixture. The inclusion of structural units containing the residue of an α,β-ethylenically unsaturated carboxylic acid in the dispersant allows the dispersant to contain at least one carboxylic acid group that can assist in providing stability to the dispersion.

[0053] The addition polymer may include a constituent unit containing a residue of an alkyl ester of (meth) acrylic acid having 1 to 3 carbon atoms in an alkyl group. Non-limiting examples of an alkyl ester of (meth) acrylic acid having 1 to 3 carbon atoms in an alkyl group include methyl (meth) acrylate and ethyl (meth) acrylate. The constituent unit containing a residue of an alkyl ester of (meth) acrylic acid having 1 to 3 carbon atoms in an alkyl group may account for at least 20 weight %, for example at least 30 weight %, for example at least 40 weight %, for example at least 45 weight %, for example at least 50 weight %, and may be no more than 98 weight %, for example no more than 96 weight %, for example no more than 90 weight %, for example no more than 80 weight %, for example no more than 75 weight %, based on the gross weight of the addition polymer. The constituent units containing the residue of an alkyl ester of (meth)acrylic acid having 1 to 3 carbon atoms in the alkyl group may account for 20 to 98% by weight, such as 30 to 96% by weight, such as 30 to 90% by weight, 40 to 90% by weight, such as 40 to 80% by weight, such as 45 to 75% by weight, based on the total weight of the addition polymer. The addition polymer may be derived from a reaction mixture containing an alkyl ester of (meth)acrylic acid having 1 to 3 carbon atoms in the alkyl group in an amount of 20 to 98% by weight, such as 30 to 96% by weight, such as 30 to 90% by weight, 40 to 90% by weight, such as 40 to 80% by weight, such as 45 to 75% by weight, based on the total weight of the polymerizable monomers used in the reaction mixture.

[0054] The addition polymer may include a constituent unit containing a residue of an alkyl (meth) acrylate having 4 to 18 carbon atoms in an alkyl group. The non-limiting examples of an alkyl (meth) acrylate having 4 to 18 carbon atoms in an alkyl group include butyl (meth) acrylate, hexyl (meth) acrylate, octyl (meth) acrylate, isodecyl (meth) acrylate, stearyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, decyl (meth) acrylate and dodecyl (meth) acrylate. The constituent unit containing a residue of an alkyl (meth) acrylate having 4 to 18 carbon atoms in an alkyl group may account for at least 2 weight %, for example, at least 5 weight %, for example, at least 10 weight %, for example, at least 15 weight %, for example, at least 20 weight %, and may be no more than 70 weight %, for example, no more than 60 weight %, for example, no more than 50 weight %, for example, no more than 40 weight %, for example, no more than 35 weight %, based on the gross weight of the addition polymer. The constituent units comprising the residue of an alkyl (meth)acrylate having 4 to 18 carbon atoms in the alkyl group may account for 2 to 70% by weight, such as 2 to 60% by weight, such as 5 to 50% by weight, 10 to 40% by weight, such as 15 to 35% by weight, based on the total weight of the addition polymer. The addition polymer may be derived from a reaction mixture comprising an alkyl (meth)acrylate having 4 to 18 carbon atoms in the alkyl group in an amount of 2 to 70% by weight, such as 2 to 60% by weight, such as 5 to 50% by weight, 10 to 40% by weight, such as 15 to 35% by weight, based on the total weight of the polymerizable monomers used in the reaction mixture.

[0055] The addition polymer may include a constituent unit containing a residue of a hydroxyalkyl ester. The non-limiting examples of hydroxyalkyl esters include hydroxyethyl (meth) acrylate and hydroxypropyl (meth) acrylate. The constituent unit comprising the residue of a hydroxyalkyl ester may account for at least 0.5% by weight, such as at least 1% by weight, such as at least 2% by weight, and may be no more than 30% by weight, such as no more than 20% by weight, such as no more than 10% by weight, such as no more than 5% by weight, based on the total weight of the addition polymer. The constituent unit comprising the residue of a hydroxyalkyl ester may account for 0.5% to 30% by weight, such as 1% to 20% by weight, such as 2% to 20% by weight, 2% to 10% by weight, such as 2% to 5% by weight, based on the total weight of the addition polymer. The addition polymer may be derived from a reaction mixture, and the amount of the hydroxyalkyl ester included in the mixture is 0.5% to 30% by weight, such as 1% to 20% by weight, such as 2% to 20% by weight, 2% to 10% by weight, such as 2% to 5% by weight, based on the total weight of the polymerizable monomers used for the reaction mixture. The inclusion of structural units containing the residue of a hydroxyalkyl ester in the dispersant allows the dispersant to contain at least one hydroxyl group (although the hydroxyl group may also be incorporated by other means). The hydroxyl groups resulting from the inclusion of the hydroxyalkyl ester (or incorporation by other means) may react with a separately added crosslinking agent comprising a functional group reactive with the hydroxyl group, such as an aminoplast, a phenoplast, a polyepoxide and a blocked polyisocyanate, or with an N-alkoxymethylamide group or a blocked isocyanate group present in the addition polymer when a self-crosslinking monomer having a group reactive with the hydroxyl group is incorporated into the addition polymer.

[0056] The addition polymer may include constituent units containing residues of ethylenically unsaturated monomers with heterocyclic groups. Non-limiting examples of ethylenically unsaturated monomers with heterocyclic groups include epoxy-functional ethylenically unsaturated monomers, such as (meth) glycidyl acrylate, vinyl pyrrolidone and vinyl caprolactam, etc. The constituent units containing residues of ethylenically unsaturated monomers with heterocyclic groups may account for at least 0.5 weight %, such as at least 1 weight %, such as at least 5 weight %, such as at least 8 weight %, and may not exceed 99 weight %, such as not more than 50 weight %, such as not more than 40 weight %, such as not more than 30 weight %, such as not more than 27 weight %, based on the total weight of the addition polymer. The constituent units containing residues of ethylenically unsaturated monomers with heterocyclic groups may account for 0.5% to 99 weight %, such as 0.5% to 50 weight %, such as 1% to 40 weight %, such as 5% to 30 weight %, 8% to 27 weight %, based on the total weight of the addition polymer. The addition polymer can be derived from a reaction mixture comprising an ethylenically unsaturated monomer having a heterocyclic group in an amount of 0.5 to 50 wt %, such as 1 to 40 wt %, such as 5 to 30 wt %, 8 to 27 wt %, based on the total weight of polymerizable monomers used in the reaction mixture.

[0057] As described above, the addition polymer may include a constituent unit containing a residue of a self-crosslinking monomer, and the addition polymer may include a self-crosslinking addition polymer. As used herein, the term "self-crosslinking monomer" refers to a monomer that is incorporated with other functional groups present on a dispersant to form a crosslinked functional group between the dispersant or more than one dispersant. Non-limiting examples of self-crosslinking monomers include N-alkoxymethyl (meth) acrylamide monomers, such as N-butoxymethyl (meth) acrylamide and N-isopropoxymethyl (meth) acrylamide, and self-crosslinking monomers containing blocked isocyanate groups, such as isocyanato (meth) ethyl acrylate, wherein the isocyanate group reacts with a compound that is unblocked at a curing temperature ("blocking"). Examples of suitable blocking agents include ε-caprolactone and methyl ethyl ketoxime. The constituent units comprising the residues of the self-crosslinking monomers may account for at least 0.5% by weight, such as at least 1% by weight, such as at least 2% by weight, and may not exceed 30% by weight, such as not more than 20% by weight, such as not more than 10% by weight, such as not more than 5% by weight, based on the total weight of the addition polymer. The constituent units comprising the residues of the self-crosslinking monomers may account for 0.5% to 30% by weight, such as 1% to 20% by weight, such as 2% to 20% by weight, 2% to 10% by weight, such as 2% to 5% by weight, based on the total weight of the addition polymer. The addition polymer may be derived from a reaction mixture comprising the self-crosslinking monomer in an amount of 0.5% to 30% by weight, such as 1% to 20% by weight, such as 2% to 20% by weight, 2% to 10% by weight, such as 2% to 5% by weight, based on the total weight of the polymerizable monomers used in the reaction mixture.

[0058] The addition polymer may include constituent units containing residues of other α,β-ethylenically unsaturated monomers. Non-limiting examples of other α,β-ethylenically unsaturated monomers include vinyl aromatic compounds such as styrene, α-methylstyrene, α-chlorostyrene and vinyltoluene; organic nitriles such as acrylonitrile and methacrylonitrile; allyl monomers such as allyl chloride and allyl cyanide; monomeric dienes such as 1,3-butadiene and 2-methyl-1,3-butadiene; and acetoacetoxyalkyl (meth) acrylates such as acetoacetoxyethyl methacrylate (AAEM) (which can be self-crosslinked). The constituent units containing residues of other α,β-ethylenically unsaturated monomers may account for at least 0.5% by weight, such as at least 1% by weight, such as at least 2% by weight, and may not exceed 30% by weight, such as not more than 20% by weight, such as not more than 10% by weight, such as not more than 5% by weight, based on the total weight of the addition polymer. The structural units comprising residues of other α,β-ethylenically unsaturated monomers may represent 0.5 to 30 wt%, such as 1 to 20 wt%, such as 2 to 20 wt%, 2 to 10 wt%, such as 2 to 5 wt%, based on the total weight of the addition polymer. The addition polymer may be derived from a reaction mixture comprising other α,β-ethylenically unsaturated monomers in an amount of 0.5 to 30 wt%, such as 1 to 20 wt%, such as 2 to 20 wt%, 2 to 10 wt%, such as 2 to 5 wt%, based on the total weight of the polymerizable monomers used in the reaction mixture.

[0059] The monomers and their relative amounts may be selected so that the resulting addition polymer has a Tg of 100°C or less, typically -50°C to +70°C, such as -50°C to 0°C. A lower Tg, below 0°C, may be desirable to ensure acceptable battery performance at low temperatures.

[0060] The addition polymer can be prepared by conventional free radical initiated solution polymerization techniques, wherein the polymerizable monomer is dissolved in a second organic medium comprising a solvent or a mixture of solvents, and polymerized in the presence of a free radical initiator until the conversion is complete. The second organic medium for preparing the addition polymer can be the same as the organic medium present in the slurry composition, so that the composition of the organic medium is not changed by the addition of the addition polymer solution. For example, the second organic medium can comprise the same primary solvent and cosolvent in the same proportion as the organic medium of the slurry composition. Alternatively, the second organic medium for preparing the addition polymer can be different and distinguished from the organic medium of the slurry composition. The second organic medium for making the addition polymer can comprise any suitable organic solvent or a mixture of solvents, including those discussed above about the organic medium, such as triethyl phosphate.

[0061] Examples of free radical initiators are those which are soluble in the monomer mixture, such as azobisisobutyronitrile, azobis(α,γ-methylvaleronitrile), tert-butyl perbenzoate, tert-butyl peracetate, benzoyl peroxide, di-tert-butyl peroxide and tert-amylperoxy 2-ethylhexyl carbonate.

[0062] Optionally, chain transfer agents such as alkyl mercaptans, such as tert-dodecyl mercaptan, ketones, such as methyl ethyl ketone, chlorocarbons, such as chloroform, which are soluble in the monomer mixture, may be used. Chain transfer agents provide control over molecular weight to obtain products having the desired viscosity for various coating applications. Tert-dodecyl mercaptan is preferred because it results in high conversion of monomer to polymer product.

[0063] To prepare the addition polymer, the solvent may first be heated to reflux and a mixture of polymerizable monomers containing a free radical initiator may be slowly added to the refluxing solvent. The reaction mixture is then maintained at the polymerization temperature to reduce the free monomer content, for example to less than 1.0% and typically less than 0.5%, based on the total weight of the mixture of polymerizable monomers.

[0064] For use in the slurry composition of the present invention, the dispersant prepared as described above generally has a weight average molecular weight of about 5000 to 500,000 g / mol, such as 10,000 to 100,000 g / mol, and 25,000 to 50,000 g / mol.

[0065] The dispersant may be present in the binder in an amount of 2 to 20 wt %, such as 5 to 15 wt %, based on the total weight of the binder solids.

[0066] As described above, the slurry composition may optionally further comprise a crosslinking agent added separately to react with the dispersant. The crosslinking agent should be soluble or dispersible in the liquid medium and react with the active hydrogen groups of the dispersant, such as carboxylic acid groups and hydroxyl groups (if present). Non-limiting examples of suitable crosslinking agents include aminoplast resins, blocked polyisocyanates and polyepoxides.

[0067] Examples of aminoplast resins used as crosslinking agents are those formed by reacting triazines such as melamine or benzoguanamine with formaldehyde. These reaction products contain reactive N-hydroxymethyl groups. Typically, these reactive groups are etherified with methanol, ethanol, butanol (including mixtures thereof) to modify their reactivity. For the chemical preparation and uses of aminoplast resins, see "The Chemistry and Applications of Amino Crosslinking Agents or Aminoplast", Vol. V, Part II, p. 21 et seq., Dr. Oldring, ed.; John Wiley & Sons / CitaTechnology Limited, London, 1998. These resins can be obtained under the trademark For example, MAPRENAL MF980 is commercially available and is marketed under the trademark For example, CYMEL 303 and CYMEL 1128 are available from Cytec Industries.

[0068] Blocked polyisocyanate crosslinkers are typically diisocyanates such as toluene diisocyanate, 1,6-hexamethylene diisocyanate and isophorone diisocyanate, including their isocyanate dimers and trimers, in which the isocyanate groups are reacted ("blocked") with materials such as ε-caprolactone and methyl ethyl ketoxime. At the curing temperature, the blocking agent unblocks, exposing isocyanate functional groups reactive with hydroxyl functional groups attached to the (meth)acrylic polymer. Blocked polyisocyanate crosslinkers are commercially available from Covestro as DESMODUR BL.

[0069] Examples of polyepoxy crosslinkers are epoxy-containing (meth)acrylic polymers such as those prepared by copolymerization of glycidyl methacrylate with other vinyl monomers, polyglycidyl ethers of polyhydroxyphenols such as the diglycidyl ether of bisphenol A; and cycloaliphatic polyepoxides such as 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate and bis(3,4-epoxy-6-methylcyclohexyl-methyl)adipate.

[0070] In addition to promoting crosslinking of the dispersant, crosslinkers, including those associated with crosslinking monomers and separately added crosslinkers, react with hydrophilic groups of the dispersant, such as active hydrogen functional groups, preventing these groups from absorbing moisture which can be problematic in lithium ion batteries.

[0071] The separately added crosslinking agent may be present in the binder in an amount of up to 15% by weight, for example from 1 to 15% by weight, the % by weight being based on the total weight of binder solids.

[0072] The binder typically has a resin solids content of 30% to 80% by weight, such as 40% to 70% by weight, based on the total weight of the binder dispersion. As used herein, the term "resin solids" may be used synonymously with "binder solids" and includes fluoropolymers, adhesion promoters, and dispersants, if present, and cross-linking agents added separately. As used herein, the term "binder dispersion" refers to a dispersion of the binder solids in the liquid medium. The fluoropolymer may be present in the binder in an amount of 40% to 96% by weight, such as 50% to 90% by weight; the adhesion promoter may be present in the slurry composition in an amount of 10% to 60% by weight, 20% to 60% by weight, such as 30% to 60% by weight, such as 10% to 50% by weight, such as 15% to 40% by weight, such as 20% to 30% by weight, such as 35% to 35% by weight; the dispersant may be present in an amount of 2% to 20% by weight, such as 5% to 15% by weight; and the crosslinking agent added separately may be present in an amount of up to 15% by weight, such as 1% to 15% by weight, the weight % being based on the total weight of the binder solids. The liquid medium may be present in the binder dispersion in an amount of 20% to 70% by weight, such as 30% to 60% by weight, based on the total weight of the binder dispersion.

[0073] Binder solids may be present in the slurry in an amount of 1 to 20 wt %, such as 1 to 10 wt %, such as 5 to 10 wt %, based on the total solids weight of the slurry.

[0074] The slurry composition of the present invention may optionally further comprise a conductive agent. Non-limiting examples of conductive agents include carbonaceous materials such as activated carbon, carbon black, such as acetylene black and furnace black, graphite, graphene, carbon nanotubes, carbon fibers, fullerenes, and combinations thereof. The conductive material may also include any activated carbon having a high surface area, such as a BET surface area greater than 100 m 2 As used herein, the term "BET surface area" refers to a specific surface area determined by nitrogen adsorption according to the ASTM D3663-78 standard based on the Brunauer-Emmett-Teller method described in the journal "The Journal of the American Chemical Society", 60, 309 (1938). In some examples, the conductive carbon may have a BET surface area of ​​100 m 2 / g to 1,000m 2 / g, for example 150m 2 / g to 600m 2 / g, for example 100m 2 / g to 400m 2 / g, for example 200m 2 / g to 400m 2In some examples, the conductive carbon may have a BET surface area of ​​about 200 m 2 / g. A suitable conductive carbon material is LITX200, commercially available from Cabot Corporation. The conductive carbon material may be present in the slurry in an amount of 2 to 20 wt%, typically 5 to 10 wt%, based on the total solid weight of the slurry.

[0075] The conductive agent may be present in the slurry in an amount of 1 to 20 wt %, such as 5 to 10 wt %, based on the total solids weight of the slurry.

[0076] The slurry composition may be in the form of an electrode slurry composition comprising a binder, an electrochemically active material, and a conductive material, each as described above. The electrode slurry may contain these materials in the amounts present in the slurry composition as described above. For example, the electrode slurry composition may contain an electrochemically active material in an amount of 45% to 95% by weight, such as 70% to 98% by weight; a binder in an amount of 1% to 20% by weight, such as 1% to 10% by weight, such as 5% to 10% by weight; and a conductive agent in an amount of 1% to 20% by weight, such as 5% to 10% by weight, the weight % being based on the total solid weight of the electrode slurry composition.

[0077] An electrode slurry composition comprising a liquid medium, an electrochemically active material, a conductive material, a binder dispersion (which may include a separately added crosslinking agent), additional liquid medium as required, and optional ingredients, can be prepared by combining the ingredients to form a slurry. These materials can be mixed together by stirring using known means, such as a stirrer, a bead mill, or a high pressure homogenizer.

[0078] With regard to the mixing and stirring for making the electrode slurry composition, a mixer capable of stirring the components to a satisfactory dispersion state should be selected. The degree of dispersion can be measured with a particle gauge, and preferably the mixing and dispersion is performed to ensure that there are no aggregates above 100 microns. Examples of mixers that meet such conditions include ball mills, sand mills, pigment dispersers, grinders, extruders, rotor stators, agitators, ultrasonic dispersers, homogenizers, planetary mixers, Hobart mixers, and combinations thereof.

[0079] The slurry composition may have a solid content of at least 30% by weight, such as at least 40% by weight, such as at least 50% by weight, such as at least 55% by weight, such as at least 60% by weight, such as at least 65% by weight, such as at least 71% by weight, such as at least 75%, and may not exceed 90% by weight, such as not more than 85% by weight, such as not more than 75% by weight, the weight % being based on the total weight of the slurry composition. The slurry composition may have a solid content of 30% to 90% by weight, such as 40% to 85% by weight, such as 50% to 85% by weight, such as 55% to 85% by weight, such as 60% to 85% by weight, such as 65% to 85% by weight, such as 71% to 85% by weight, such as 75% to 85% by weight, based on the total weight of the slurry composition.

[0080] The present invention also relates to an electrode comprising a current collector and a film formed on the current collector, wherein the film is deposited from the above-mentioned electrode slurry composition. The electrode may be a positive electrode or a negative electrode, and may be manufactured by applying the above-mentioned slurry composition to the surface of the current collector to form a coating, and then drying and / or curing the coating. The coating may have a thickness of at least 1 micron, such as 1 to 500 microns (μm), such as 1 to 150 μm, such as 25 to 150 μm, such as 30 to 125 μm. The coating may include a cross-linked coating. The current collector may include a conductive material, and the conductive material may include metals, such as iron, copper, aluminum, nickel and their alloys, and stainless steel. For example, the current collector may include aluminum or copper in the form of a mesh, sheet or foil. Although the shape and thickness of the current collector are not particularly limited, the current collector may have a thickness of about 0.001 to 0.5 mm, such as a mesh, sheet or foil having a thickness of about 0.001 to 0.5 mm.

[0081] The coating film manufactured by the slurry composition of the present invention may have improved adhesion to the current collector compared to the coating film manufactured by the slurry composition not comprising the adhesion promoter of the present invention. For example, the coating film produced by the slurry composition of the present invention may improve adhesion by at least 50%, for example, at least 100%, for example, at least 200%, for example, at least 300%, for example, at least 400% compared to the coating film manufactured by the slurry composition not comprising the adhesion promoter of the present invention. As used herein, the term "adhesion" refers to the peel strength adhesion measured by the peel strength test method. According to the peel strength test method, a motor-driven test bench (EMS-303, available from Mark-10) equipped with a 10N dynamometer (5 series, model M5-2) and a 90° peeling bench is used to measure adhesion. The lateral movement of the 90° peeling bench is actively driven at the same rate as the horizontal movement of the test bench cross head, which ensures a 90° peeling angle during the entire measurement. The coating on the aluminum foil prepared as described in the Examples section below is cut into rectangular strips (1.1 inches wide x11 inches long). The coated side of the tape was adhered to a rigid aluminum substrate using 3M 444 double-sided tape (1 inch wide x 7 inches long), leaving the free end of the foil untaped. The rigid aluminum substrate was then secured to a 90° peeling station, and the free end of the foil was secured in the peeling station fixture so that a 90° angle was achieved between the instrument crosshead and the peeling station. The sample was then peeled at a rate of 50 mm / min for 2 minutes.

[0082] The current collector can be pretreated with a pretreatment composition, and then the slurry composition is deposited. As used herein, the term "pretreatment composition" refers to a composition that reacts with the current collector surface when in contact with the current collector and chemically changes it, and is bonded thereto to form a protective layer. The pretreatment composition may be a pretreatment composition comprising a IIIB and / or IVB group metal. As used herein, the term "IIIB and / or IVB group metal" refers to an element in the IIIB or IVB group of the CAS periodic table, for example, in Handbook of Chemistry and Physics, 63rd edition (1983). When applicable, the metal itself can be used, but a IIIB and / or IVB group metal compound can also be used. As used herein, the term "IIIB and / or IVB group metal compound" refers to a compound comprising an element in the IIIB or IVB group of at least one CAS periodic table. Suitable pretreatment compositions and methods for pretreating current collectors are described in US Pat. No. 9,273,399 at column 4, line 60 to column 10, line 26, the cited portions of which are incorporated herein by reference. The pretreatment composition can be used to treat a current collector used to make a positive electrode or a negative electrode.

[0083] The method of applying the slurry composition to the current collector is not particularly limited. The slurry composition can be applied by blade coating, dip coating, reverse roll coating, direct roll coating, gravure coating, extrusion coating, dipping or brushing. Although the amount of the slurry composition applied is not particularly limited, the thickness of the coating formed after the liquid medium is removed can be 25 to 150 microns (μm), for example 30 to 125 μm.

[0084] If applicable, drying and / or crosslinking of the coating film after application can be accomplished, for example, by heating at an elevated temperature, for example, at least 50°C, for example, at least 60°C, for example, 50-145°C, for example, 60-120°C, for example, 65-110°C. The heating time will depend to some extent on the temperature. Generally, higher temperatures require shorter curing times. Typically, the curing time is at least 5 minutes, for example, 5 to 60 minutes. The temperature and time should be sufficient to crosslink the dispersant in the cured film (if applicable), i.e., to form covalent bonds between co-reactive groups on the dispersant polymer chain, such as carboxylic acid groups and hydroxyl groups with N-methylol and / or N-methylol ether groups of aminoplasts, isocyanate groups of blocked polyisocyanate crosslinkers, or in the case of self-curing dispersants, N-alkoxymethylamide groups or blocked isocyanate groups. The degree of curing or crosslinking can be measured as resistance to solvents such as methyl ethyl ketone (MEK). The test is performed as described in ASTM D-540293. Record the number of double scratches back and forth. This test is generally referred to as "MEK tolerance". Therefore, dispersants and crosslinkers (including self-curing dispersants and dispersants together with crosslinkers added separately) are separated from the binder composition, and the binder composition is deposited as a film and heated to the temperature and time at which the binder film is heated. The film is then measured for MEK tolerance with the recorded number of double scratches. Therefore, the crosslinked dispersant will have a MEK tolerance of at least 50 double scratches, for example at least 75 double scratches. In addition, the crosslinked dispersant may be substantially solvent tolerant to the solvents of the above-mentioned electrolyte. Other methods for drying the coating include ambient temperature drying, microwave drying and infrared drying, and other methods for curing the coating include electron beam curing and UV curing.

[0085] During discharge of a lithium-ion storage device, lithium ions may be released from the negative electrode and carry current to the positive electrode. This process may include a process known as deintercalation. During charging, lithium ions migrate from the electrochemically active material in the positive electrode to the negative electrode, where they are embedded in the electrochemically active material present in the negative electrode. This process may include a process known as intercalation.

[0086] The present invention also relates to an electric storage device. The electric storage device according to the present invention can be manufactured by using the above-mentioned electrode prepared by the electrode slurry composition of the present invention. The electric storage device includes an electrode, a counter electrode and an electrolyte. The electrode, the counter electrode or both may contain the electrode of the present invention, as long as one electrode is a positive electrode and one electrode is a negative electrode. The electric storage device according to the present invention includes a single cell, a battery, a battery pack, a secondary battery, a capacitor and a supercapacitor.

[0087] The power storage device includes an electrolyte solution and can be manufactured according to a common method by using components such as a separator. As a more specific manufacturing method, a negative electrode and a positive electrode are assembled with a separator between them, the resulting assembly is rolled or bent according to the shape of a battery and placed in a battery container, an electrolyte solution is injected into the battery container, and the battery container is sealed. The shape of the battery may be, for example, a coin, a button or a sheet, a cylinder, a block or a flat.

[0088] The electrolyte solution may be a liquid or a gel, and the electrolyte solution that can be effectively used as a battery may be selected from known electrolyte solutions for power storage devices according to the types of the negative electrode active material and the positive electrode active material. The electrolyte solution may be a solution containing an electrolyte dissolved in a suitable solvent. The electrolyte may be a conventionally known lithium salt for lithium ion secondary batteries. Examples of lithium salts include LiClO4, LiBF4, LiPF6, LiCF3CO2, LiAsF6, LiSbF6, LiB 10 Cl 10 , LiAlCl4, LiCl, LiBr, LiB(C2H5)4, LiB(C6H5)4, LiCF3SO3, LiCH3SO3, LiC4F9SO3, Li(CF3SO2)2N, LiB4CH3SO3Li and CF3SO3Li. The solvent for dissolving the above electrolyte is not particularly limited, and examples thereof include carbonate compounds such as propylene carbonate, ethylene carbonate, butylene carbonate, dimethyl carbonate, methyl ethyl carbonate and diethyl carbonate; lactone compounds such as γ-butyl lactone; ether compounds such as trimethoxymethane, 1,2-dimethoxyethane, diethyl ether, 2-ethoxyethane, tetrahydrofuran and 2-methyltetrahydrofuran; and sulfoxide compounds such as dimethyl sulfoxide. The electrolyte concentration in the electrolyte solution may be 0.5 to 3.0 mol / L, for example 0.7 to 2.0 mol / L.

[0089] As used herein, the term "polymer" refers broadly to oligomers as well as homopolymers and copolymers. The terms "resin" and "polymer" are used interchangeably.

[0090] The terms "acrylic" and "acrylate" are used interchangeably (unless doing so would change the intended meaning) and include acrylic acid, its anhydrides and derivatives, such as their C1-C5 alkyl esters, lower alkyl substituted acrylic acid, such as C1-C2 substituted acrylic acid, such as methacrylic acid, 2-ethylacrylic acid, etc., and their C1-C4 alkyl esters, unless otherwise expressly stated. The terms "(meth)acrylic" or "(meth)acrylate" are intended to encompass both acrylic / acrylate and methacrylic / methacrylate forms of the indicated material, such as (meth)acrylate monomers. The term "(meth)acrylic polymer" refers to a polymer prepared from one or more (meth)acrylic monomers.

[0091] Molecular weights as used herein are determined by gel permeation chromatography using polystyrene standards. Unless otherwise indicated, molecular weights are weight average.

[0092] The term "glass transition temperature" as used herein is a theoretical value, which is based on the monomer composition of the monomer feed by the Fox method, according to T.G. Fox, Bull. Am. Phys. Soc. (Ser. II) 1, 123 (1956) and J. Brandrup, E.H. Immergut, Polymer Handbook 3 rd Glass transition temperature calculated from 2004-08-08 1996 edition, John Wiley, New York, 1989.

[0093] As used herein, unless otherwise defined, the term substantially free means that the component, if present, is present in an amount of less than 5 wt %, based on the total weight of the slurry composition.

[0094] As used herein, unless otherwise defined, the term substantially free means that the component, if present, is present in an amount of less than 1 wt %, based on the total weight of the slurry composition.

[0095] As used herein, unless otherwise defined, the term completely free means that the component is not present in the slurry composition, ie, 0.00 wt %, based on the total weight of the slurry composition.

[0096] As used herein, the term "total solids" refers to the non-volatile components of the slurry composition of the present invention and specifically excludes the liquid medium.

[0097] As used herein, the term "consisting essentially of includes the recited materials or steps and those materials or steps that do not materially affect the basic and novel characteristics of the claimed invention.

[0098] As used herein, the term "consisting of excludes any elements, steps or ingredients not recited.

[0099] For the purpose of detailed description, it should be understood that the present invention can take various alternative variations and step sequences, unless there is a clear contrary provision. In addition, except in any operation example or in the case of otherwise noted, all numerals, such as those representing values, amounts, percentages, ranges, sub-ranges and fractions, are also all like to be interpreted as modified with "about", even if the term does not appear explicitly. Therefore, unless there is an opposite indication, the numerical parameters listed in the following specification and the appended claims are approximate values ​​that can be changed according to the desired properties obtained according to the present invention. At least and without attempting to limit the application of the principle of equivalents to the scope of the claims, each numerical parameter should be explained at least according to the number of reported significant figures and by applying common rounding techniques. In the case of describing a closed or open numerical range in this article, all numerals, numerical values, amounts, percentages, sub-ranges and fractions in or included in the numerical range should be considered to be specifically included in and belong to the original disclosure of the application, as if these numerals, numerical values, amounts, percentages, sub-ranges and fractions have all been clearly written out.

[0100] Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the invention are approximations, the numerical values ​​set forth in the specific examples are reported as precisely as possible. Any numerical value, however, inherently contains certain errors necessarily resulting from the standard deviation found in their respective testing measurements.

[0101] As used herein, unless otherwise specified, plural terms may include their singular counterparts, and vice versa unless otherwise specified. For example, although "an" electrochemically active material, "an" fluoropolymer, "an" dispersant, "an" conductive agent, and "an" adhesion promoter are mentioned herein, combinations (i.e., multiples) of these components may be used in the present invention. In addition, in this application, the use of "or" means "and / or" unless otherwise explicitly stated, even though "and / or" may be explicitly used in certain cases.

[0102] As used herein, "comprising", "containing" and similar terms are understood to be synonymous with "comprising" in the context of the present application, and are therefore open-ended and do not exclude the presence of additional undescribed and / or unquoted elements, materials, components and / or method steps. As used herein, "consisting of..." is understood to exclude any unspecified elements, ingredients and / or method steps in the context of the present application. As used herein, "consisting essentially of..." is understood to include the specified elements, materials, ingredients and / or method steps "and those basic and novel features that do not substantially affect the content being described" in the context of the present application. Although various embodiments of the present invention are described with "comprising", embodiments consisting essentially of or embodiments consisting of are also within the scope of the present invention.

[0103] As used herein, the terms "on", "onto", "applied on", "applied onto", "formed on", "deposited on", "deposited onto", mean formed, covered, deposited and / or provided on a surface but not necessarily in contact with the surface. For example, a composition "deposited on" a substrate does not exclude the presence of one or more other intermediate coatings of the same or different composition located between the electrodepositable coating composition and the substrate.

[0104] Although specific embodiments of the present invention have been described in detail, it will be appreciated by those skilled in the art that various modifications and substitutions to those details may be developed based on the overall teachings of the present disclosure. Therefore, the specific arrangements disclosed are merely illustrative and do not limit the scope of the present invention, which is provided by the full scope of the appended claims and all equivalent forms thereof.

[0105] aspect

[0106] Each of the above features and examples and their combinations can be said to be covered by the present invention. Therefore, the present invention particularly relates to the following aspects, but is not limited thereto:

[0107] 1. A slurry composition comprising:

[0108] (a) a binder comprising a polymer dispersed in a liquid medium, the polymer comprising a fluorine-containing polymer;

[0109] (b) an adhesion promoter; and at least one of

[0110] (c1) electrochemically active materials, and

[0111] (c2) Conductive agent.

[0112] 2. The slurry composition of aspect 1, wherein the adhesion promoter comprises a polyvinylidene fluoride copolymer different from the fluorine-containing polymer of the binder.

[0113] 3. The slurry composition of aspect 2, wherein the polyvinylidene fluoride copolymer comprises constitutional units containing vinylidene fluoride and residues of at least one of the following:

[0114] (i) (meth)acrylic acid; or

[0115] (ii) Hydroxyalkyl (meth)acrylates.

[0116] 4. The slurry composition of aspect 3, wherein the (meth)acrylic acid comprises acrylic acid.

[0117] 5. The syrup composition of aspect 3 or 4, wherein the hydroxyalkyl (meth)acrylate comprises a C1-C5 hydroxyalkyl (meth)acrylate.

[0118] 6. The slurry composition of aspect 5, wherein the C1-C5 hydroxyalkyl (meth)acrylate comprises hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, or a combination thereof.

[0119] 7. The slurry composition of aspects 3 to 6, wherein the adhesion promoter comprises 50% to 99 mol % of constituent units comprising residues of vinylidene fluoride, such as 70% to 98 mol %, such as 80% to 95 mol %; and 0.01% to 10 mol % of constituent units comprising residues of (meth)acrylic acid, such as 0.02% to 5 mol %, such as 0.03% to 2 mol %, based on the total molar content of the polyvinylidene fluoride copolymer adhesion promoter.

[0120] 8. The slurry composition of aspects 3 to 6, wherein the adhesion promoter comprises 50% to 99 mol % of constituent units comprising residues of vinylidene fluoride, such as 70% to 98 mol %, such as 80% to 95 mol %; and 0.01% to 10 mol % of constituent units comprising residues of hydroxyalkyl (meth)acrylate, such as 0.02% to 5 mol %, such as 0.03% to 2 mol %, based on the total molar content of the polyvinylidene fluoride copolymer adhesion promoter.

[0121] 9. The slurry composition of aspects 3 to 6, wherein the adhesion promoter comprises 50% to 99 mol% of constituent units comprising residues of vinylidene fluoride, for example, 70% to 98 mol%, for example, 80% to 95 mol%; 0.01% to 10 mol% of constituent units comprising residues of (meth)acrylic acid, for example, 0.02% to 5 mol%, for example, 0.03% to 2 mol%; and 0.01% to 10 mol% of constituent units comprising residues of hydroxyalkyl (meth)acrylate, for example, 0.02% to 5 mol%, for example, 0.03% to 2 mol%, based on the total molar content of the polyvinylidene fluoride copolymer adhesion promoter.

[0122] 10. The slurry composition of any one of aspects 2 to 9, wherein the liquid medium comprises an organic medium.

[0123] 11. The slurry composition of aspect 10, wherein the evaporation rate of the organic medium at the dissolution temperature of the fluorine-containing polymer in the organic medium is less than 10 g / min m 2 .

[0124] 12. The slurry composition of aspect 10 or 11, wherein the evaporation rate of the organic medium at 180° C. is higher than 80 g / min m 2 .

[0125] 13. The slurry composition of any one of aspects 2 to 12, wherein the organic medium comprises butylpyrrolidone, trialkyl phosphates such as triethyl phosphate, 1,2,3-triacetoxypropane, 3-methoxy-N,N-dimethylpropionamide, ethyl acetoacetate, γ-butyrolactone, propylene glycol methyl ether, cyclohexanone, propylene carbonate, dimethyl adipate, propylene glycol methyl ether acetate, dibasic acid ester (DBE), dibasic acid ester 5,4-hydroxy-4-methyl-2-pentanone, propylene glycol diacetate, dimethyl phthalate, methyl isoamyl ketone, ethyl propionate, 1-ethoxy-2-propanol, dipropylene glycol dimethyl ether, saturated and unsaturated linear and cyclic ketones, diisobutyl ketone, acetate, tripropylene glycol methyl ether, diethylene glycol ethyl ether acetate, or a combination thereof.

[0126] 14. The slurry composition of any one of aspects 2 to 13, wherein the organic medium comprises a main solvent and a co-solvent, the main solvent comprises butyl pyrrolidone, a trialkyl phosphate such as triethyl phosphate, 3-methoxy-N,N-dimethylpropionamide, 1,2,3-triacetoxypropane, or a combination thereof, and the co-solvent comprises ethyl acetoacetate, γ-butyrolactone, propylene glycol methyl ether, dipropylene glycol methyl ether, propylene glycol monopropyl ether, diethylene glycol monobutyl ether, ethylene glycol monohexyl ether, or a combination thereof.

[0127] 15. The slurry composition of aspect 14, wherein the main solvent is present in an amount of 50 to 99 wt %, such as 65 to 90 wt %, such as 75 to 85 wt %, and the co-solvent is present in an amount of 1 to 50 wt %, such as 10 to 35 wt %, such as 15 to 25 wt %, each based on the total weight of the organic medium.

[0128] 16. The slurry composition of any one of aspects 13 to 15, wherein the organic medium comprises triethyl phosphate.

[0129] 17. The slurry composition of aspect 14 or 15, wherein the organic medium comprises triethyl phosphate as a main solvent and ethyl acetoacetate as a co-solvent.

[0130] 18. The slurry composition of aspect 1, wherein the adhesion promoter comprises an acid functional polyolefin.

[0131] 19. The syrup composition of aspect 18, wherein the acid functional polyolefin comprises an ethylene-acrylic acid copolymer.

[0132] 20. The syrup composition of aspect 19, wherein the ethylene-acrylic acid copolymer comprises a structural unit containing 20 wt% of acrylic acid based on the total weight of the ethylene-acrylic acid copolymer.

[0133] 21. The slurry composition of any one of aspects 18 to 20, wherein the liquid medium comprises an aqueous medium.

[0134] 22. The slurry composition of any one of aspects 1 to 21, wherein the conductive agent comprises graphite, carbon black such as acetylene black and furnace black, graphene, carbon nanotubes, or a combination thereof.

[0135] 23. The slurry composition of any one of aspects 1 to 21, wherein the conductive agent comprises a BET surface area of ​​100 m 2 / g to 1000m 2 / g of conductive carbon material.

[0136] 24. The slurry composition of any one of aspects 1 to 23, wherein the slurry is substantially free of isophorone.

[0137] 25. The slurry composition of any one of aspects 1 to 24, wherein the slurry is substantially free of N-methyl-2-pyrrolidone.

[0138] 26. A slurry composition as described in any of the preceding aspects, wherein the amount of binder solids present in the slurry composition is 1% to 20% by weight, such as 1% to 10% by weight, such as 5% to 10% by weight, based on the total solid weight of the slurry, based on the total solid weight of the slurry.

[0139] 27. The slurry composition of any one of aspects 1 to 25, wherein the adhesion promoter is present in the slurry composition in an amount of 10% to 60% by weight, such as 20% to 60% by weight, such as 30% to 60% by weight, such as 10% to 50% by weight, such as 15% to 40% by weight, such as 20% to 30% by weight or such as 35% to 35% by weight, based on the total weight of the binder solids.

[0140] 28. The slurry composition of any one of aspects 1 to 25, wherein the binder solids are present in the slurry composition in an amount of 1% to 20% by weight, such as 1% to 10% by weight, such as 5% to 10% by weight, based on the total solid weight of the slurry, and the fluoropolymer is present in the binder in an amount of 40% to 96% by weight, such as 50% to 90% by weight; the dispersant is present in an amount of 2% to 20% by weight, such as 5% to 15% by weight; and the adhesion promoter is present in the slurry composition in an amount of 10% to 60% by weight, 20% to 60% by weight, such as 30% to 60% by weight, such as 10% to 50% by weight, such as 15% to 40% by weight, such as 20% to 30% by weight, such as 35% to 35% by weight, the weight % being based on the total weight of the binder solids.

[0141] 29. The slurry composition of any one of aspects 1 to 25, wherein the binder solids are present in the slurry composition in an amount of 1% to 20% by weight, such as 1% to 10% by weight, such as 5% to 10% by weight, based on the total solid weight of the slurry, and the fluoropolymer is present in the binder in an amount of 40% to 96% by weight, such as 50% to 90% by weight; the dispersant is present in an amount of 2% to 20% by weight, such as 5% to 15% by weight; the adhesion promoter is present in the slurry composition in an amount of 10% to 60% by weight, 20% to 60% by weight, such as 30% to 60% by weight, such as 10% to 50% by weight, such as 15% to 40% by weight, such as 20% to 30% by weight, such as 35% to 35% by weight; and the cross-linking agent added separately may be present in an amount of up to 15% by weight, such as 1% to 15% by weight, the weight % being based on the total weight of the binder solids.

[0142] 30. The slurry composition of any one of the preceding aspects, wherein the electrochemically active material comprises a material capable of incorporating lithium.

[0143] 31. The slurry composition of aspect 30, wherein the material capable of incorporating lithium comprises LiCoO2, LiNiO2, LiFePO4, LiCoPO4, LiMnO2, LiMn2O4, Li(NiMnCo)O2, Li(NiCoAl)O2, carbon-coated LiFePO4, or a combination thereof.

[0144] 32. The slurry composition of any one of aspects 1 to 29, wherein the electrochemically active material comprises a material capable of lithium conversion.

[0145] 33. The slurry composition of aspect 32, wherein the material capable of lithium conversion comprises sulfur, LiO2, FeF2 and FeF3, Si, aluminum, tin, SnCo, Fe3O4, or a combination thereof.

[0146] 34. The slurry composition of any one of aspects 1 to 29, wherein the electrochemically active material comprises graphite, a silicon compound, tin, a tin compound, sulfur, a sulfur compound, or a combination thereof.

[0147] 35. The slurry composition of any of the preceding aspects, wherein the electrochemically active material is present in the slurry composition in an amount of 45 to 95 wt%, such as 70 to 98 wt%, based on the total solid weight of the slurry.

[0148] 36. The slurry composition of any one of the preceding aspects, wherein the conductive agent is present in the slurry composition in an amount of 1 to 20 wt%, such as 5 to 10 wt%, based on the total solid weight of the slurry.

[0149] 37. An electrode comprising:

[0150] (a) a current collector; and

[0151] (b) A film formed on the current collector, wherein the film is deposited from the slurry composition of any one of the preceding aspects.

[0152] 38. The electrode of aspect 37, wherein the current collector (a) comprises copper or aluminum in the form of a mesh, sheet or foil.

[0153] 39. The electrode of aspect 37 or 38, wherein the electrode comprises a positive electrode.

[0154] 40. The electrode of aspect 37 or 38, wherein the electrode comprises a negative electrode.

[0155] 41. The electrode of any one of aspects 37 to 40, wherein the membrane is cross-linked.

[0156] 42. The electrode of any one of aspects 37 to 41, wherein the current collector is pretreated with a pretreatment composition.

[0157] 43. The electrode of any one of aspects 37 to 42, wherein the thickness of the film is at least 1 μm, such as 1 to 500 μm, such as 1 to 150 μm, such as 25 to 150 μm, such as 30 to 125 μm.

[0158] 44. An electricity storage device comprising:

[0159] (a) The electrode of any one of aspects 37 to 43;

[0160] (b) a counter electrode; and

[0161] (c) Electrolyte.

[0162] 45. The electricity storage device of aspect 44, wherein the electrolyte (c) comprises a lithium salt dissolved in a solvent.

[0163] 46. ​​The power storage device of aspect 45, wherein the lithium salt is dissolved in an organic carbonate.

[0164] 47. The electricity storage device of any one of aspects 44 to 46, wherein the electricity storage device comprises a single battery.

[0165] 48. The electricity storage device of any one of aspects 44 to 46, wherein the electricity storage device comprises a battery pack.

[0166] 49. The electricity storage device of any one of aspects 44 to 46, wherein the electricity storage device comprises a secondary battery.

[0167] 50. The electricity storage device of any one of aspects 44 to 46, wherein the electricity storage device comprises a capacitor.

[0168] 51. The electricity storage device of any one of aspects 44 to 46, wherein the electricity storage device comprises a supercapacitor.

[0169] The following examples illustrate the invention without, however, being considered to limit the invention to their details. Unless otherwise indicated, all percentages and parts in the following examples and throughout the specification are by weight. Example

[0170] Example 1. Synthesis of a (meth)acrylic copolymer dispersant having a theoretical glass transition temperature (Tg) of 3.5°C

[0171]

[0172]

[0173] To a suitable reaction vessel equipped with a stirrer, reflux condenser, thermometer, heating mantle and nitrogen inlet was added Charge 1 at ambient temperature. The temperature was then raised to a set point of 122°C, at which point the initiator premix of Charge 2 was added over 210 minutes, and Charge 3 was added over 180 minutes. After the addition of Charge 2 was complete, Charge 4 was added and the reaction vessel was maintained at a set point of 122°C for 60 minutes. Charge 5 was then added over 30 minutes, followed by Charge 6, maintained at a set point of 122°C for an additional 90 minutes. After cooling to below 100°C, Charge 7 was added over 10 minutes and stirring was continued for 15 minutes, followed by Charge 8 added over 90 minutes. Thereafter, the reaction temperature was cooled to 50°C. The theoretical solids content of the dispersant composition so formed was 23.25 wt%.

[0174] In each dispersant embodiment, the solid content of the dispersant composition is measured by the following process. An aluminum weighing pan from Fisher Scientific is weighed with an analytical balance. The weight of the empty pan is recorded to four decimal places. Approximately 0.5 g of dispersant and 3.5 g of acetone are added to the weighing pan. The weight of the pan and the dispersant solution are recorded to four decimal places. The pan containing the dispersant solution is placed in a laboratory oven, the oven temperature is set at 110° C., and dried for 1 hour. The weight of the weighing pan and the dried dispersant is weighed with an analytical balance. The weight of the pan and the dried dispersant is recorded to four decimal places. Solids are determined using the following equation: % solids = 100x [(weight of pan and dried dispersant) - (weight of empty pan)] / [(weight of pan and dispersant solution) - (weight of empty pan)].

[0175] Example 2. Preparation of Binder Dispersion

[0176] 23.3 grams of deionized water, 225.7 grams of the dispersant composition of Example 1 and 0.47 grams of Drewplus Y-281 defoamer (available from Ashland) were added to a 1 liter plastic container. The resulting mixture was fully stirred with a Cowles blade. Such mixing was continued while 150.5 grams of polyvinylidene fluoride powder PG-11 (available from Arkema) were gradually added. Mixing was continued for another 20 minutes after all polyvinylidene fluoride powders were added. Then Resimene HM-2608 melamine crosslinker (available from Ineos Melamines, LLC) was added to the binder dispersion in a dry solid weight ratio of PVDF: dispersant: melamine 70 / 25 / 5.

[0177] Example 3 (Comparative) Preparation of Binder Solution in NMP

[0178] To a plastic container was added solvent grade N-methyl-2-pyrrolidone (available from Ashland, 1141.44 grams). While stirring with a Cowles blade, polyvinylidene fluoride, Kynar HSV-900 (available from Arkema, 58.56 grams) was added in portions. Stirring was continued until the polymer was completely dissolved.

[0179] Example 4. Adhesion promoter composition

[0180]

[0181] To a suitable reaction vessel equipped with an agitator, reflux condenser, thermometer, heating jacket and nitrogen inlet was added Charge 1 at ambient temperature. The temperature was then raised to 40°C over 20 minutes with continued mixing. After mixing at 40°C for 20 minutes, Charge 2 was added over 5 minutes. The reaction vessel was then heated to 75°C over 15 minutes. Charge 3 was then added over 10 minutes and the reaction vessel was heated to 90°C over 40 minutes. The batch was further heated to 95°C over 30 minutes and mixed for an additional 30 minutes. The batch was then cooled and filtered through a 5 micron filter paper. The theoretical solids content of the composition was 20 wt %.

[0182] The solid content of all compositions except this dispersant composition is measured by the following process. Weigh the aluminum weighing pan from Fisher Scientific with an analytical balance. Record the weight of the empty pan to four decimal places. Add about 1g of dispersion to the weighing pan. Record the weight of the pan and the wet dispersion to four decimal places. Put the pan containing the slurry into a laboratory oven, set the oven temperature at 120 degrees Celsius and dry for 1 hour. Weigh the weighing pan and the dried dispersion with an analytical balance. Record the weight of the pan and the dried slurry to four decimal places. Solids are determined with the following equation: % solids = 100x [(the weight of the pan and the dried dispersion) - (the weight of the empty pan)] / [(the weight of the pan and the wet dispersion) - (the weight of the empty pan)].

[0183] Example 5 (Comparative). Preparation of cathode using a water-based PVDF dispersion containing 0% (weight percentage, based on the total weight of resin solids in the binder) of adhesion promoter

[0184] To a plastic cup was added 1.69 grams of ethanol, 21.97 grams of deionized water, 1.06 grams of the binder dispersion of Example 2, and 1.16 grams of Acrysol ASE-60 (acid-containing, cross-linked acrylic emulsion copolymer thickener available from The Dow Chemical Company) neutralized with sodium hydroxide. Such a blend was placed in a dual asymmetric centrifugal mixer and mixed at 2000 rpm for 5 minutes. After mixing, 28.62 grams of cathode active powder lithium nickel manganese cobalt oxide (NCM 111, available from BASF) was added to the mixture, and the resulting combination was mixed in a dual asymmetric centrifugal mixer at 2000 rpm for 5 minutes. After mixing, 2.54 grams of Timcal C-NERGY TM Super C65 conductive carbon (available from TIMCAL) was added and the blend was placed in a dual asymmetric centrifugal mixer and mixed at 2000 rpm for 10 minutes. Next, 2.26 grams of butyl CELLOSOLVE TM Glycol ether and 0.71 g DOWANOL TMPnB glycol ether (both available from The Dow Chemical Co.) was added and the mixture was mixed in a dual asymmetric centrifugal mixer at 2000 rpm for 5 minutes.

[0185] A wet film was prepared by coating such a formulated slurry on an aluminum foil using a doctor blade. The wet film was flashed at 25°C for 15 minutes, then heated in an oven to a temperature of 60°C for at least 30 minutes, and then heated in an oven to a maximum temperature of 246°C for 10 minutes. After cooling, the average dry film thickness was determined to be 53 microns from 5 measurements using a micrometer.

[0186] The cell performance data and the peel strength of the coating are shown in Table 1.

[0187] Example 6. Preparation of electrodes using a water-based binder dispersion containing 10% adhesion promoter (weight percent, based on the total weight of resin solids in the binder) of the total binder package

[0188] 1.15 grams of ethanol, 13.75 grams of deionized water, 1.20 grams of the binder dispersion of Example 2, 1.49 grams of Acrysol ASE-60 neutralized with sodium hydroxide, and 0.41 grams of the adhesion promoter composition of Example 4 were added to the plastic cup. Such a blend was placed in a dual asymmetric centrifugal mixer and mixed at 2000 rpm for 5 minutes. After mixing, 36.72 grams of cathode active powder lithium nickel manganese cobalt oxide NMC-111 (electrochemically active material (Li(NiMnCo)O2), available from BASF) was added to the mixture, and the resulting combination was mixed at 2000 rpm for 5 minutes in a dual asymmetric centrifugal mixer. After mixing, 3.26 grams of Timcal C-NERGY TM Super C65 conductive carbon was added and the blend was placed in a dual asymmetric centrifugal mixer and mixed at 2000 rpm for 10 minutes. Next, 1.54 g of butyl CELLOSOLVE TM Glycol ether and 0.48 g DOWANOL TM PnB glycol ether was added and the mixture was mixed in a dual asymmetric centrifugal mixer at 2000 rpm for 5 minutes.

[0189] A wet film was prepared by coating such a formulated slurry on a pre-cleaned aluminum foil using a doctor blade. The wet film was flashed at 25°C for 15 minutes, then heated to a temperature of 60°C in an oven for at least 30 minutes, and then heated to a maximum temperature of 246°C in an oven for 10 minutes. After cooling, the average dry film thickness was determined to be 52 microns from 5 measurements using a micrometer. The battery performance data and peel strength of the electrode are shown in Table 1.

[0190] Example 7. Preparation of electrodes using a water-based PVDF dispersion containing 30% adhesion promoter (weight percent, based on the total weight of resin solids in the binder) of the total binder package

[0191] To a plastic cup was added 0.90 g of ethanol, 9.43 g of deionized water, 0.99 g of the binder dispersion of Example 2, 1.65 g of Acrysol ASE-60 neutralized with sodium hydroxide (available from Dow Chemical Co.), and 1.35 g of the adhesion promoter composition of Example 4. Such a blend was placed in a dual asymmetric centrifugal mixer and mixed at 2000 rpm for 5 minutes. After mixing, 40.50 g of cathode active powder NMC-111 was added to the mixture, and the resulting combination was mixed at 2000 rpm for 5 minutes in a dual asymmetric centrifugal mixer. After mixing, 3.60 g of Timcal C-NERGY TM Super C65 conductive carbon was added and the blend was placed in a dual asymmetric centrifugal mixer and mixed at 2000 rpm for 10 minutes. Next, 1.20 g of butyl CELLOSOLVE TM Glycol ether and 0.37 g DOWANOL TM PnB glycol ether was added and the mixture was mixed in a dual asymmetric centrifugal mixer at 2000 rpm for 5 minutes.

[0192] A wet film was prepared by coating such a formulated slurry using a doctor blade on a pre-cleaned aluminum foil. The wet film was flashed at 25°C for 15 minutes, then heated to a temperature of 60°C in an oven for at least 30 minutes, and then heated to a maximum temperature of 246°C in an oven for 10 minutes. After cooling, the average dry film thickness was determined to be 52 microns from 5 measurements using a micrometer. The battery performance data and the peel strength of the coating are shown in Table 1.

[0193] Example 8. Preparation of electrodes using a water-based PVDF dispersion containing 60% adhesion promoter (weight percent, based on the total weight of resin solids in the binder) of the total binder package

[0194] 0.90 g of ethanol, 8.42 g of deionized water, 0.49 g of the binder dispersion of Example 2, 1.81 g of Acrysol ASE-60 neutralized with sodium hydroxide, and 2.70 g of the adhesion promoter composition of Example 4 were added to the plastic cup. Such a blend was placed in a dual asymmetric centrifugal mixer and mixed at 2000 rpm for 5 minutes. After mixing, 40.50 g of cathode active powder NMC-111 was added to the mixture, and the resulting combination was mixed at 2000 rpm for 5 minutes in a dual asymmetric centrifugal mixer. After mixing, 3.60 g of Timcal C-NERGY TMSuper C65 conductive carbon was added and the blend was placed in a dual asymmetric centrifugal mixer and mixed at 2000 rpm for 10 minutes. Next, 1.20 g of butyl CELLOSOLVE TM Glycol ether and 0.37 g DOWANOL TM PnB glycol ether was added and the mixture was mixed in a dual asymmetric centrifugal mixer at 2000 rpm for 5 minutes.

[0195] A wet film was prepared by coating such a formulated slurry using a doctor blade on a pre-cleaned aluminum foil. The wet film was flashed at 25°C for 15 minutes, then heated to a temperature of 60°C in an oven for at least 30 minutes, and then heated to a maximum temperature of 246°C in an oven for 10 minutes. After cooling, the average dry film thickness was determined to be 49 microns from 5 measurements using a micrometer. The battery performance data and the peel strength of the coating are shown in Table 1.

[0196] Example 9. Preparation of electrodes using a water-based PVDF dispersion containing 100% adhesion promoter (weight percent, based on the total weight of resin solids in the binder) of the total binder package

[0197] 0.79 g of ethanol, 7.28 g of deionized water, and 4.68 g of the acrylic acid-ethylene copolymer dispersion of Example 4 were added to a plastic cup. Such a blend was placed in a dual asymmetric centrifugal mixer and mixed at 2000 rpm for 5 minutes. After mixing, 42.12 g of cathode active powder lithium nickel manganese cobalt oxide (NCM 111) was added to the mixture, and the resulting combination was mixed in a dual asymmetric centrifugal mixer at 2000 rpm for 5 minutes. After mixing, 3.74 g of Timcal C-NERGY TM Super C65 conductive carbon was added and the blend was placed in a dual asymmetric centrifugal mixer and mixed at 2000 rpm for 10 minutes. Next, 1.06 g of butyl CELLOSOLVE TM Glycol ether and 0.33 g DOWANOL TM PnB glycol ether was added and the mixture was mixed in a dual asymmetric centrifugal mixer at 2000 rpm for 5 minutes.

[0198] A wet film was prepared by coating such a formulated slurry using a doctor blade on a pre-cleaned aluminum foil. The wet film was flashed at 25°C for 15 minutes, then heated to a temperature of 60°C in an oven for at least 30 minutes, and then heated to a maximum temperature of 246°C in an oven for 10 minutes. After cooling, the average dry film thickness was determined to be 52 microns from 5 measurements using a micrometer. The battery performance data and the peel strength of the coating are shown in Table 1 below.

[0199] Example 10 (Comparative) Preparation of cathode using PVDF made from PVDF dissolved in NMP (Example 3)

[0200] Add NMP (25.22 g), the binder solution of Example 3 (10.08 g) and conductive carbon C-NERGY to the plastic cup. TM Super C65 (2.02 g). Such blend was placed in a dual asymmetric centrifugal mixer and mixed at 2000 rpm for 10 minutes. Cathode active powder NMC-111 (22.68 g) was added to the mixed blend, and the resulting combination was mixed in a dual asymmetric centrifugal mixer at 2000 rpm for 10 minutes to produce a formulated slurry.

[0201] A wet film was prepared by coating such a formulated slurry on a pre-cleaned aluminum foil using a doctor blade. The wet film was heated in an oven to a maximum temperature of 150°C for at least 5 minutes. After cooling, the average dry film thickness was determined to be 38 microns from 5 measurements using a micrometer. The battery performance data and the peel strength of the coating are shown in Table 1.

[0202] Peel Strength Test Procedure : The peel strength was measured using the peel strength test method and recorded in Table 1.

[0203] Coin Cell Testing Process : The dried coated foils were passed through a roll calender (Innovative Machine Corporation) to achieve 25-30% compression. After vacuum drying, two coin-type half-cells were assembled per dried coated foil using lithium metal as the negative electrode and 1 mole of LiPF6 in ethylene carbonate, diethyl carbonate, and dimethyl carbonate solvents as the electrolyte. The coin cells were then tested on a battery tester (Arbin Instruments) using a potential window of 4.2-3 volts for 5 cycles, each at currents corresponding to 0.2C, 0.4C, 0.8C, 1.6C, 3.2C, and 6.4C charge / discharge rates, followed by 50 cycles at a current corresponding to a 1C rate. The discharge capacity in milliampere-hours per gram of lithium oxide nickel manganese cobalt 1:1:1 was calculated from the average of the first 5 cycles at each C rate. "C rate" refers to the current value required for a battery with constant capacitance to be completely discharged in a time equal to the inverse of the C rate value in hours. For example, a discharge capacitance of 0.2C refers to the capacitance of the dry coated film in milliamp-hours per gram of lithium nickel manganese cobalt oxide at the current value required to completely discharge the battery in 5 hours. Similarly, a discharge capacitance of 1C refers to the capacitance of the dry coated film in milliamp-hours per gram of lithium nickel manganese cobalt oxide at the current value required to completely discharge the battery in 1 hour.

[0204] The average values ​​of the discharge capacitance of the higher capacitance coin half-cells for two replicate cells for a given dry coated foil are reported in Table 1. The capacitance retention was calculated from the quotient of the discharge capacitance after the first charge-discharge cycle at 1 C and the last charge-discharge cycle at 1 C and reported as a percentage value according to the following equation: 100×first cycle capacitance / last cycle capacitance.

[0205] Table 1 shows the peel force for 1" wide electrodes and discharge data for coin cells made from the example electrodes. The table shows the specific capacitance (mA-hours per gram) of the cells at various discharge C-rates (per hour).

[0206] Table 1.

[0207]

[0208] Example 11. Synthesis of a (meth)acrylic polymer dispersant having a theoretical glass transition temperature (Tg) of -12.4°C

[0209]

[0210]

[0211] A suitable reaction vessel equipped with a stirrer, condenser, thermometer, heating mantle and nitrogen inlet was charged with Charge 1 at ambient temperature. The temperature was then raised to 120°C at which time the initiator premix of Charge 2 was added over 185 minutes. Five minutes after the start of Charge 2, Charge 3 was added over 180 minutes. After completion of Charges 2 and 3, Charge 4 was added, followed by Charge 5 over 60 minutes, followed by Charge 6, and maintained at 120°C for an additional 60 minutes. After cooling to below 90°C, the dispersant composition so formed had a theoretical solids content of 51.32 wt%.

[0212] Example 12. Synthesis of an acrylic polymer dispersant having a theoretical glass transition temperature (Tg) of -12.2°C

[0213] This polymer was prepared in the same manner as the polymer of Example 11, except that Feed 3 consisted of the following monomers:

[0214]

[0215] Example 13. Synthesis of a (meth)acrylic polymer dispersant having a theoretical glass transition temperature (Tg) of -12.4°C

[0216] This polymer was prepared in the same manner as the polymer of Example 11, except that Feed 3 consisted of the following monomers:

[0217]

[0218] Examples 14-16. Preparation of Binder Dispersion

[0219] 41.64 grams of triethyl phosphate and 26.85 grams of the (meth) acrylic copolymer dispersant composition of Example 12 were added to a 2-liter plastic container. The resulting mixture was fully stirred with a Cowles blade while maintaining a moderate vortex. This mixing was continued while adding 32.90 grams of polyvinylidene fluoride powder, PVDF T-1 (Inner Mongolia 3F Wanhao Fluorochemical Co., Ltd) in a plurality of small portions. After all polyvinylidene fluoride powders were added, mixing was continued for another 30 minutes.

[0220] By a similar procedure, PVDF dispersions were prepared from a combination of the (meth)acrylic copolymer dispersant composition and PVDF in a specified weight ratio as shown in the following table.

[0221]

[0222] Example 17 (Comparative) Preparation of Electrode Using Slurry Without Adhesion Promoter

[0223] Triethyl phosphate (14.83 g) and the binder dispersion of Example 15 (2.15 g) were added to a plastic cup. Conductive carbon LITX200 (0.72 g, available from Cabot Corp.) was added in two portions, and the blend after each was mixed in a dual asymmetric centrifugal mixer at 2000 rpm for 5 minutes. Cathode active powder NMC-111 (22.33 g) was added in two portions to the mixed blend, and the blend after each was mixed in a dual asymmetric centrifugal mixer at 2000 rpm for 5 minutes to make a formulated slurry. The total non-volatile content of the slurry was 60%. The final ratio of NMC-111: LITX200: binder dry solids was 93:3:4.

[0224] A wet film was prepared by coating the slurry thus formulated on a pre-cleaned aluminum foil using a doctor blade. The wet film was heated in an oven to a maximum temperature of 120°C for at least 10 minutes. After cooling, an average dry film thickness of 106 microns was determined by 5 measurements with a micrometer. The dry film was pressed to a film thickness of 87 microns in a roller calender (Innovative Machine Co.). The adhesion of the resulting film was measured using the peel strength test method. After such testing, the coating exhibited a 90 degree peel strength of 7.9 N / m.

[0225] Example 18. Slurry composition and electrode

[0226] Triethyl phosphate (12.46 g), the binder dispersion of Example 15 (1.83 g), and an adhesion promoter composition (2.68 g) of a vinylidene fluoride-acrylic acid copolymer (Solef 5130 available from Solvay) dissolved in triethyl phosphate at 5.40% w / w were added to a plastic cup. Conductive carbon LITX200 (0.72 g) was added in two portions, and the blend after each was mixed in a dual asymmetric centrifugal mixer at 2000 rpm for 5 minutes. Cathode active powder NMC-111 (22.32 g) was added in two portions to the mixed blend, and the blend after each was mixed in a dual asymmetric centrifugal mixer at 2000 rpm for 5 minutes to make a formulated slurry. The total non-volatile content of such a slurry was 60% by weight. The final weight ratio of NMC-111: LITX200: binder dry solids was 93:3:4.

[0227] A wet film was prepared by knife coating such a formulated slurry on a pre-cleaned aluminum foil. The wet film was heated in an oven to a maximum temperature of 120°C for at least 10 minutes. After cooling, the average dry film thickness was determined to be 109 microns from 5 measurements using a micrometer. The dried film was calendered to a film thickness of 90 microns, and the 90 degree peel strength measured using the peel strength test method was 16.7 N / m.

[0228] Example 19. Slurry composition and electrode

[0229] Triethyl phosphate (10.13 g), the binder dispersion of Example 15 (1.51 g), and an adhesion promoter composition (5.33 g) of vinylidene fluoride-acrylic acid copolymer (Solef 5130) dissolved in triethyl phosphate at 5.40% w / w were added to a plastic cup. Conductive carbon LITX200 (0.72 g) was added in two portions, and the blend after each was mixed in a dual asymmetric centrifugal mixer at 2000 rpm for 5 minutes. Cathode active powder NMC-111 (22.33 g) was added in two portions to the mixed blend, and the blend after each was mixed in a dual asymmetric centrifugal mixer at 2000 rpm for 5 minutes to make a formulated slurry. The total non-volatile content of such a slurry was 60% by weight. The final weight ratio of NMC-111: LITX200: binder dry solids was 93:3:4.

[0230] A wet film was prepared by knife coating such a formulated slurry on a pre-cleaned aluminum foil. The wet film was heated in an oven to a maximum temperature of 120°C for at least 10 minutes. After cooling, the average dry film thickness was determined to be 106 microns from 5 measurements using a micrometer. The dried film was calendered to a film thickness of 88 microns, and the 90 degree peel strength measured using the peel strength test method was 29.3 N / m.

[0231] Embodiment 20

[0232] Triethyl phosphate (7.00 g), the binder dispersion of Example 15 (1.08 g), and an adhesion promoter composition (8.89 g) of vinylidene fluoride-acrylic acid copolymer (Solef 5130) dissolved in triethyl phosphate at 5.40% w / w were added to a plastic cup. Conductive carbon LITX200 (0.72 g) was added in two portions, and the blend after each was mixed in a dual asymmetric centrifugal mixer at 2000 rpm for 5 minutes. Cathode active powder NMC-111 (22.34 g) was added in two portions to the mixed blend, and the blend after each was mixed in a dual asymmetric centrifugal mixer at 2000 rpm for 5 minutes to make a formulated slurry. The total non-volatile content of such a slurry was 60% by weight. The final weight ratio of NMC-111: LITX200: binder dry solids was 93:3:4.

[0233] A wet film was prepared by coating such a formulated slurry on a pre-cleaned aluminum foil using a doctor blade. The wet film was heated in an oven to a maximum temperature of 120°C for at least 10 minutes. After cooling, the average dry film thickness was determined to be 106 microns from 5 measurements using a micrometer. The dried film was calendered to a film thickness of 90 microns, and the 90 degree peel strength measured using the peel strength test method was 39.0 N / m.

[0234] Embodiment 21

[0235] Triethyl phosphate (1.87 g), the binder dispersion of Example 16 (0.77 g), an adhesion promoter composition of vinylidene fluoride-acrylic acid copolymer (Solef 5130) dissolved in triethyl phosphate at 6.30% w / w (1.49 g), and the dispersant composition of Example 11 diluted to 0.63% w / w in triethyl phosphate (15.52 g) were added to the plastic cup. Conductive carbon LITX200 (1.66 g) was added in two portions, and the blend after each time was mixed in a dual asymmetric centrifugal mixer at 2000 rpm for 5 minutes. The cathode active powder NMC-111 (18.72 g) was added in two portions to the mixed blend, and the blend after each time was mixed in a dual asymmetric centrifugal mixer at 2000 rpm for 5 minutes to make a formulated slurry. The total non-volatile content of such a slurry was 52% by weight. The final weight ratio of NMC-111:LITX200:binder dry solids was 90:8:2.

[0236] A wet film was prepared by knife coating such a formulated slurry on a pre-cleaned aluminum foil. The wet film was heated in an oven to a maximum temperature of 120°C for at least 10 minutes. After cooling, the average dry film thickness was determined to be 65 microns from 5 measurements using a micrometer. The dried film was calendered to a film thickness of 45 microns, and the 90 degree peel strength measured using the peel strength test method was 9.8 N / m.

[0237] Embodiment 22

[0238] Triethyl phosphate (9.41 g), the binder dispersion of Example 16 (0.53 g), an adhesion promoter composition of vinylidene fluoride-acrylic acid copolymer (Solef 5130) dissolved in triethyl phosphate at 6.30% w / w (3.59 g), and the dispersant composition of Example 11 diluted to 0.63% w / w in triethyl phosphate (6.21 g) were added to a plastic cup. Conductive carbon LITX200 (1.66 g) was added in two portions, and the blend after each time was mixed in a dual asymmetric centrifugal mixer at 2000 rpm for 5 minutes. Cathode active powder NMC-111 (18.75 g) was added in two portions to the mixed blend, and the blend after each time was mixed in a dual asymmetric centrifugal mixer at 2000 rpm for 5 minutes to make a formulated slurry. The total non-volatile content of such a slurry was 52% by weight. The final weight ratio of NMC-111:LITX200:binder dry solids was 90:8:2.

[0239] A wet film was prepared by knife coating such a formulated slurry on a pre-cleaned aluminum foil. The wet film was heated in an oven to a maximum temperature of 120°C for at least 10 minutes. After cooling, the average dry film thickness was determined to be 70 microns from 5 measurements using a micrometer. The dried film was calendered to a film thickness of 49 microns and the 90 degree peel strength measured using the peel strength test method was 15.4 N / m.

[0240] Embodiment 23

[0241] Triethyl phosphate (0.69 g), the binder dispersion of Example 16 (0.43 g), an adhesion promoter composition of vinylidene fluoride-acrylic acid copolymer (Solef 5130) dissolved in triethyl phosphate at 6.30% w / w (2.98 g), and the dispersant composition of Example 11 diluted to 0.63% w / w in triethyl phosphate (15.56 g) were added to the plastic cup. Conductive carbon LITX200 (1.67 g) was added in two portions, and the blend after each time was mixed at 2000 rpm in a dual asymmetric centrifugal mixer for 5 minutes. The cathode active powder NMC-111 (18.76 g) was added to the mixed blend in two portions, and the blend after each time was mixed at 2000 rpm in a dual asymmetric centrifugal mixer for 5 minutes to make a formulated slurry. The total non-volatile content of such a slurry was 52% by weight. The final weight ratio of NMC-111:LITX200:binder dry solids was 90:8:2.

[0242] A wet film was prepared by knife coating such a formulated slurry on a pre-cleaned aluminum foil. The wet film was heated in an oven to a maximum temperature of 120°C for at least 10 minutes. After cooling, the average dry film thickness was determined to be 66 microns from 5 measurements using a micrometer. The dried film was calendered to a film thickness of 47 microns and the 90 degree peel strength measured using the peel strength test method was 5.5 N / m.

[0243] Embodiment 24

[0244] Triethyl phosphate (10.73 g), the binder dispersion of Example 16 (0.90 g), an adhesion promoter composition (1.78 g) of vinylidene fluoride-acrylic acid copolymer (Solef 5130) dissolved in triethyl phosphate at 6.30% w / w, and the dispersant composition (6.24 g) of Example 11 diluted to 0.63% w / w in triethyl phosphate were added to a plastic cup. Conductive carbon LITX200 (1.67 g) was added in two portions, and the blend after each time was mixed in a dual asymmetric centrifugal mixer at 2000 rpm for 5 minutes. The cathode active powder NMC-111 (18.78 g) was added in two portions to the mixed blend, and the blend after each time was mixed in a dual asymmetric centrifugal mixer at 2000 rpm for 5 minutes to make a formulated slurry. The total non-volatile content of such a slurry was 52% by weight. The final weight ratio of NMC-111:LITX200:binder dry solids was 90:8:2.

[0245] A wet film was prepared by knife coating such a formulated slurry on a pre-cleaned aluminum foil. The wet film was heated in an oven to a maximum temperature of 120°C for at least 10 minutes. After cooling, the average dry film thickness was determined to be 72 microns from 5 measurements using a micrometer. The dried film was calendered to a film thickness of 52 microns and the 90 degree peel strength measured using the peel strength test method was 12.5 N / m.

[0246] Embodiment 25

[0247] Triethyl phosphate (13.95 g), the binder dispersion of Example 16 (0.56 g), an adhesion promoter composition of vinylidene fluoride-acrylic acid copolymer (Solef 5130) dissolved in triethyl phosphate at 6.30% w / w (2.60 g), and the dispersant composition of Example 11 (0.09 g) were added to a plastic cup. Conductive carbon Denka Black (1.46 g) was added in two portions, and the blend after each time was mixed in a dual asymmetric centrifugal mixer at 2000 rpm for 5 minutes. Cathode active powder NMC-111 (16.40 g) was added in two portions to the mixed blend, and the blend after each time was mixed in a dual asymmetric centrifugal mixer at 2000 rpm for 5 minutes to make a formulated slurry. The total non-volatile content of such a slurry was 52% by weight. The final weight ratio of NMC-111: Denka Black: binder dry solids was 90:8:2.

[0248] A wet film was prepared by knife coating such a formulated slurry on a pre-cleaned aluminum foil. The wet film was heated in an oven to a maximum temperature of 120°C for at least 10 minutes. After cooling, the average dry film thickness was determined to be 95 microns from 5 measurements using a micrometer. The dried film was calendered to a film thickness of 52 microns and the 90 degree peel strength measured using the peel strength test method was 2.2 N / m.

[0249] Example 26 (Comparative) Preparation of Electrode Using Slurry Without Binder or Dispersant

[0250] Triethyl phosphate (2.53 g) and an adhesion promoter composition (13.45 g) of vinylidene fluoride-acrylic acid copolymer (Solef 5130) dissolved in triethyl phosphate at 5.00% w / w were added to a plastic cup. Conductive carbon LITX200 (0.51 g) was added in one portion and the blend was mixed in a dual asymmetric centrifugal mixer at 2000 rpm for 5 minutes. Cathode active powder NMC-111 (15.62 g) was added to the mixed blend in two portions, and the blend after each was mixed in a dual asymmetric centrifugal mixer at 2000 rpm for 5 minutes to make a formulated slurry. The total non-volatile content of such a slurry was 52% by weight. The final weight ratio of NMC-111: LITX200: binder dry solids was 93:3:4.

[0251] A wet film was prepared by knife coating such a formulated slurry on a pre-cleaned aluminum foil. The wet film was heated in an oven to a maximum temperature of 120°C for at least 10 minutes. After cooling, the average dry film thickness was determined to be 89 microns from 5 measurements using a micrometer. The dried film was calendered to a film thickness of 65 microns, and the 90 degree peel strength measured using the peel strength test method was 60.4 N / m.

[0252] Example 27 (Comparative) Preparation of Electrode Using Slurry Without Adhesion Promoter

[0253] Triethyl phosphate (14.71 g) and the binder dispersion of Example 14 (2.27 g) were added to a plastic cup. Conductive carbon LITX200 (0.72 g) was added in two portions, and the blend after each was mixed in a dual asymmetric centrifugal mixer at 2000 rpm for 5 minutes. Cathode active powder NMC-111 (22.33 g) was added in two portions to the mixed blend, and the blend after each was mixed in a dual asymmetric centrifugal mixer at 2000 rpm for 5 minutes to make a formulated slurry. The total non-volatile content of such a slurry was 60% by weight. The final weight ratio of NMC-111: LITX200: binder dry solids was 93:3:4.

[0254] A wet film was prepared by knife coating such a formulated slurry on a pre-cleaned aluminum foil using a doctor blade. The wet film was heated in an oven to a maximum temperature of 68°C for at least 10 minutes. After cooling, the average dry film thickness was determined to be 74 microns from 5 measurements using a micrometer. The dried film was calendered to a film thickness of 57 microns and the 90 degree peel strength measured using the peel strength test method was 11.2 N / m.

[0255] Embodiment 28

[0256] Triethyl phosphate (12.37 g), the binder dispersion of Example 14 (1.93 g) and an adhesion promoter composition (2.67 g) of vinylidene fluoride-acrylic acid copolymer (Solef 5130) dissolved in triethyl phosphate at 5.40% w / w were added to a plastic cup. Conductive carbon LITX200 (0.72 g) was added in two portions, and the blend after each was mixed in a dual asymmetric centrifugal mixer at 2000 rpm for 5 minutes. Cathode active powder NMC-111 (22.32 g) was added in two portions to the mixed blend, and the blend after each was mixed in a dual asymmetric centrifugal mixer at 2000 rpm for 5 minutes to make a formulated slurry. The total non-volatile content of such a slurry was 60% by weight. The final weight ratio of NMC-111: LITX200: binder dry solids was 93:3:4.

[0257] A wet film was prepared by knife coating such a formulated slurry on a pre-cleaned aluminum foil. The wet film was heated in an oven to a maximum temperature of 68°C for at least 10 minutes. After cooling, the average dry film thickness was determined to be 74 microns from 5 measurements using a micrometer. The dried film was calendered to a film thickness of 56 microns and the 90 degree peel strength measured using the peel strength test method was 36.5 N / m.

[0258] Embodiment 29

[0259] Triethyl phosphate (10.04 g), the binder dispersion of Example 14 (1.58 g), and an adhesion promoter composition (5.33 g) of vinylidene fluoride-acrylic acid copolymer (Solef 5130) dissolved in triethyl phosphate at 5.40% w / w were added to a plastic cup. Conductive carbon LITX200 (0.72 g) was added in two portions, and the blend after each was mixed in a dual asymmetric centrifugal mixer at 2000 rpm for 5 minutes. Cathode active powder NMC-111 (22.33 g) was added in two portions to the mixed blend, and the blend after each was mixed in a dual asymmetric centrifugal mixer at 2000 rpm for 5 minutes to make a formulated slurry. The total non-volatile content of such a slurry was 60% by weight. The final weight ratio of NMC-111: LITX200: binder dry solids was 93:3:4.

[0260] A wet film was prepared by knife coating such a formulated slurry on a pre-cleaned aluminum foil. The wet film was heated in an oven to a maximum temperature of 68°C for at least 10 minutes. After cooling, the average dry film thickness was determined to be 75 microns from 5 measurements using a micrometer. The dried film was calendered to a film thickness of 57 microns, and the 90 degree peel strength measured using the peel strength test method was 51.6 N / m.

[0261] Embodiment 30

[0262] Triethyl phosphate (6.95 g), the binder dispersion of Example 14 (1.14 g), and an adhesion promoter composition (8.90 g) of vinylidene fluoride-acrylic acid copolymer (Solef 5130) dissolved in triethyl phosphate at 5.40% w / w were added to a plastic cup. Conductive carbon LITX200 (0.73 g) was added in two portions, and the blend after each was mixed in a dual asymmetric centrifugal mixer at 2000 rpm for 5 minutes. Cathode active powder NMC-111 (22.33 g) was added in two portions to the mixed blend, and the blend after each was mixed in a dual asymmetric centrifugal mixer at 2000 rpm for 5 minutes to make a formulated slurry. The total non-volatile content of such a slurry was 60% by weight. The final weight ratio of NMC-111: LITX200: binder dry solids was 93:3:4.

[0263] A wet film was prepared by knife coating such a formulated slurry on a pre-cleaned aluminum foil using a doctor blade. The wet film was heated in an oven to a maximum temperature of 68°C for at least 10 minutes. After cooling, the average dry film thickness was determined to be 72 microns from 5 measurements using a micrometer. The dried film was calendered to a film thickness of 56 microns and the 90 degree peel strength measured using the peel strength test method was 79.9 N / m.

[0264] Examples 17-20 show that adding more adhesion promoter produces higher peel strengths compared to dispersed PVDF alone for LITX 200 conductive carbon at 93:3:4. Examples 21-24 show that adhesion promoter produces higher peel strengths using LITX / NMC at 90:8:2. Example 25 shows that adhesion promoter produces higher peel strengths with Denka black at 90:8:2. Example 26 (comparative) shows that adhesion promoter alone does not produce high peel strengths in TEP using NMC and LITX at 93:3:4. Examples 27-30 show that using LITX 20 conductive carbon at 93:3:4, more adhesion promoter produces higher peel strengths compared to dispersed PVDF alone, but at lower baking temperatures and thinner films.

[0265] Those skilled in the art will appreciate that, based on the above disclosure, various modifications and variations may be made without departing from the broad inventive concepts described and illustrated herein. Therefore, it should be understood that the foregoing disclosure is merely an illustration of various exemplary aspects of the present application, and that those skilled in the art may easily make various modifications and variations within the spirit and scope of the present application and the appended claims.

Claims

1. A slurry composition comprising: (a) electrochemically active materials; (b) a binder comprising a polymer dispersed in an organic medium, the polymer comprising a fluorine-containing polymer; and (c) adhesion promoters; The slurry composition is substantially free of N-methyl-2-pyrrolidone.

2. The slurry composition of claim 1, wherein the adhesion promoter comprises a polyvinylidene fluoride copolymer.

3. The slurry composition of claim 2, wherein the polyvinylidene fluoride copolymer comprises constituent units comprising vinylidene fluoride and residues of at least one of: (i) (meth)acrylic acid; or (ii) Hydroxyalkyl (meth)acrylates.

4. The slurry composition of claim 3, wherein the (meth)acrylic acid comprises acrylic acid. 5 . The slurry composition of claim 3 , wherein the hydroxyalkyl (meth)acrylate comprises a hydroxy C1-C5 alkyl (meth)acrylate. 6 . The slurry composition of claim 5 , wherein the hydroxy C1-C5 alkyl (meth)acrylate comprises hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, or a combination thereof.

7. The slurry composition of claim 1, wherein the evaporation rate of the organic medium at the dissolution temperature of the fluorine-containing polymer dispersed in the organic medium is less than 10 g / min m 2 .

8. The slurry composition of claim 1, wherein the evaporation rate of the organic medium at 180°C is greater than 80 g / min m 2 .

9. The slurry composition of claim 1, wherein the organic medium comprises butyl pyrrolidone, trialkyl phosphate, 1,2,3-triacetoxypropane, 3-methoxy-N,N-dimethylpropionamide, ethyl acetoacetate, γ-butyrolactone, propylene glycol methyl ether, cyclohexanone, propylene carbonate, dimethyl adipate, propylene glycol methyl ether acetate, dibasic acid ester (DBE), dibasic acid ester 5,4-hydroxy-4-methyl-2-pentanone, propylene glycol diacetate, dimethyl phthalate, methyl isoamyl ketone, ethyl propionate, 1-ethoxy-2-propanol, dipropylene glycol dimethyl ether, saturated and unsaturated linear and cyclic ketones, diisobutyl ketone, acetate, tripropylene glycol methyl ether, diethylene glycol ethyl ether acetate, or a combination thereof.

10. The slurry composition of claim 1, wherein the organic medium comprises a main solvent and a co-solvent, the main solvent comprising butyl pyrrolidone, trialkyl phosphate, 3-methoxy-N,N-dimethylpropionamide, 1,2,3-triacetoxypropane, or a combination thereof, and the co-solvent comprises ethyl acetoacetate, γ-butyrolactone, propylene glycol methyl ether, dipropylene glycol methyl ether, propylene glycol monopropyl ether, diethylene glycol monobutyl ether, ethylene glycol monohexyl ether, or a combination thereof.

11. The slurry composition of claim 1, wherein the adhesion promoter comprises an acid-functional polyolefin.

12. The syrup composition of claim 11, wherein the acid-functional polyolefin comprises ethylene-acrylic acid copolymer. 13 . The syrup composition of claim 11 , wherein the ethylene-acrylic acid copolymer comprises a structural unit containing 20 wt % of acrylic acid based on the total weight of the ethylene-acrylic acid copolymer. The slurry composition of claim 1 , further comprising a conductive agent.

15. The slurry composition of claim 14, wherein the conductive agent comprises graphite, acetylene black, furnace black, graphene, carbon nanotubes, or a combination thereof.

16. The slurry composition of claim 14, wherein the conductive agent comprises a surface area of ​​100 m 2 / g to 1000m 2 / g of conductive carbon material.

17. The slurry composition of claim 1, wherein the slurry is substantially free of isophorone.

18. The slurry composition of claim 1, wherein the slurry is substantially free of N-methyl-2-pyrrolidone.

19. A slurry composition comprising: (a) conductive agent; (b) a binder comprising a polymer dispersed in an organic medium, the polymer comprising a fluorine-containing polymer; and (c) adhesion promoters; The slurry composition is substantially free of N-methyl-2-pyrrolidone.

20. An electrode comprising: (a) a current collector; and (b) A film formed on the current collector, wherein the film is deposited from the slurry composition of claim 14.

21. The electrode of claim 20, wherein the current collector (a) comprises copper or aluminum in the form of a mesh, sheet or foil.

22. The electrode of claim 20, wherein the electrode comprises a positive electrode.

23. The electrode of claim 20, wherein the electrode comprises a negative electrode.

24. The electrode of claim 20, wherein the membrane is cross-linked.

25. The electrode of claim 20, wherein the current collector is pretreated with a pretreatment composition.

26. An electric storage device comprising: (a) The electrode according to claim 20; (b) a counter electrode; and (c) Electrolyte.

27. The electricity storage device of claim 26, wherein the electrolyte (c) comprises a lithium salt dissolved in a solvent.

28. The electricity storage device of claim 27, wherein the lithium salt is dissolved in an organic carbonate.

29. The energy storage device of claim 26, wherein the energy storage device comprises a single battery.

30. The electricity storage device of claim 26, wherein the electricity storage device comprises a battery.

31. The electricity storage device of claim 26, wherein the electricity storage device comprises a secondary battery.

32. The energy storage device of claim 26, wherein the energy storage device comprises a capacitor.

33. The energy storage device of claim 26, wherein the energy storage device comprises a supercapacitor.

34. A slurry composition comprising: (a) electrochemically active materials; (b) a binder comprising a polymer dispersed in an organic medium, the polymer comprising a fluorine-containing polymer; and (c) adhesion promoters; wherein the slurry composition is substantially free of N-methyl-2-pyrrolidone; and The organic medium includes butyl pyrrolidone, trialkyl phosphate, 1,2,3-triacetoxypropane, 3-methoxy-N,N-dimethylpropionamide, ethyl acetoacetate, γ-butyrolactone, propylene glycol methyl ether, cyclohexanone, propylene carbonate, dimethyl adipate, propylene glycol methyl ether acetate, dibasic acid ester (DBE), dibasic acid ester 5,4-hydroxy-4-methyl-2-pentanone, propylene glycol diacetate, dimethyl phthalate, methyl isoamyl ketone, ethyl propionate, 1-ethoxy-2-propanol, dipropylene glycol dimethyl ether, saturated and unsaturated linear and cyclic ketones, diisobutyl ketone, acetate, tripropylene glycol methyl ether, diethylene glycol ethyl ether acetate, or a combination thereof.

35. A slurry composition comprising: (a) conductive agent; (b) a binder comprising a polymer dispersed in an organic medium, the polymer comprising a fluorine-containing polymer; and (c) adhesion promoters; wherein the slurry is substantially free of N-methyl-2-pyrrolidone; and The organic medium includes butyl pyrrolidone, trialkyl phosphate, 1,2,3-triacetoxypropane, 3-methoxy-N,N-dimethylpropionamide, ethyl acetoacetate, γ-butyrolactone, propylene glycol methyl ether, cyclohexanone, propylene carbonate, dimethyl adipate, propylene glycol methyl ether acetate, dibasic acid ester (DBE), dibasic acid ester 5,4-hydroxy-4-methyl-2-pentanone, propylene glycol diacetate, dimethyl phthalate, methyl isoamyl ketone, ethyl propionate, 1-ethoxy-2-propanol, dipropylene glycol dimethyl ether, saturated and unsaturated linear and cyclic ketones, diisobutyl ketone, acetate, tripropylene glycol methyl ether, diethylene glycol ethyl ether acetate, or a combination thereof.

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