Electrode film mixture containing solvent additives for use in energy storage devices and method thereof

Abstract

This invention provides improved electrodes with reduced curvature and folds, energy storage devices, and methods for preparing electrodes. [Solution] Provided are electrodes for use in energy storage devices, comprising an electrode film formed from an electrode film mixture containing water and a solvent additive, and a method thereof. Electrodes utilizing water and a solvent additive in an amount of at most about 5% by weight help reduce compressive stress, folds and / or curvature during formation, thereby achieving improved electrode shape and / or strength.

Description

[Technical Field]

[0001] [Cross-reference of related applications] This application claims priority to U.S. Patent Application No. 19 / 027,871, filed on 17 January 2025, entitled “ELECTRODE FILM MIXTURES WITH SOLVENT ADDITIVES FOR USE IN ENERGY STORAGE DEVICES, AND METHODS THEREOF,” which is incorporated herein by reference in its entirety for any purpose. [Background technology]

[0002] Compressive stress and forces in electrodes are typical challenges known to occur during wet electrode manufacturing processes. Conventional wet electrode processes involve mixing a slurry or electrode film mixture, coating a current collector with the electrode film mixture, drying the electrode film mixture on the current collector, and calendering to form the electrode. Such processes cause bending and folds in the electrode, adding difficulties during the processing and coating of the current collector. For example, Figure 1 is a schematic diagram showing a multi-lane electrode 100 including electrode films 110A and 110B placed on a current collector 120, where the electrode films 110A and 110B are subjected to compressive stress 125 during drying. As shown in Figure 1, the compressive stress 125 induces folds 150 in the exposed portion of the multi-lane electrode 100 and bending (i.e., negative curvature) 175 in the coated portion of the multi-lane electrode 100.

[0003] Currently, such problems are addressed by adjusting manufacturing conditions and processing steps (e.g., increasing the humidity of the factory floor during manufacturing and limiting idle time between processing steps). However, these adjustments require that the manufacturing conditions and steps be performed during narrow processing windows, which can increase the probability of loss of electrochemical performance and may be impractical under certain circumstances, such as maintenance that involves interruptions to dehumidification conditions. Therefore, improved electrodes with reduced curvature and folds are desirable. [Overview of the Initiative] [Means for solving the problem]

[0004] For the purpose of summarizing the advantages achieved beyond the present invention and the prior art, specific purposes and advantages of the present invention are described herein. Not all such purposes or advantages can be achieved in any particular embodiment of the present invention. Therefore, for example, those skilled in the art will recognize that the present invention may be embodied or implemented to achieve or optimize one or more advantages as taught herein, without necessarily achieving other purposes or advantages as taught or suggested herein.

[0005] In one embodiment, an electrode film mixture is described. The electrode film mixture comprises a binder, water, an electrode active material, and a solvent additive, wherein the electrode film mixture contains at most about 5% by weight of the solvent additive.

[0006] In some embodiments, the solvent additive comprises a compound selected from the group consisting of ethylene carbonate (EC), propylene carbonate (PC), vinylene carbonate (VC), vinyl ethylene carbonate (VEC), fluoroethylene carbonate (FEC), dimethyl carbonate (DMC), diethyl carbonate (DEC), ethyl methyl carbonate (EMC), 1,3 - propene sultone (PRS), dimethoxyethane (DME), methyl acetate (MA), methyl propionate (MP), ethyl acetate (EA), methyl butyrate (MB), and combinations thereof.

[0007] In some embodiments, the solvent additive has a boiling point temperature of at least about 80 °C. In some embodiments, the solvent additive is soluble in water. In some embodiments, the electrode film mixture comprises the solvent additive in an amount of at least about 0.1 wt%. In some embodiments, the electrode film mixture comprises water in an amount of at least about 0.1 wt%. In some embodiments, the electrode film mixture further comprises a conductive additive.

[0008] In another aspect, an electrode preform is described. The electrode preform comprises an electrode film mixture disposed on a current collector.

[0009] In another aspect, an electrode is described. The electrode comprises an electrode film comprising a binder, an electrode active material, residual water, and a residual solvent additive, and a current collector, wherein the electrode film is disposed on the current collector.

[0010] In some embodiments, the electrode comprises the residual solvent additive in an amount of at most about 0.1 wt%. In some embodiments, the electrode comprises the residual water in an amount of at most about 0.1 wt%. In some embodiments, the electrode has a stress curvature value of at most about 1.5 m-1. In some embodiments, the electrode film has a thickness of at least about 120 μm.

[0011] In another aspect, an energy storage device is described. The energy storage device includes an electrode, a second electrode, a separator disposed between the electrode and the second electrode, an electrolyte, and a housing, and the electrode, the second electrode, the separator, and the electrolyte are disposed within the housing.

[0012] In some embodiments, the electrolyte comprises a compound selected from the group consisting of ethylene carbonate (EC), propylene carbonate (PC), vinylene carbonate (VC), vinyl ethylene carbonate (VEC), fluoroethylene carbonate (FEC), dimethyl carbonate (DMC), diethyl carbonate (DEC), ethyl methyl carbonate (EMC), 1,3 - propene sultone (PRS), dimethoxyethane (DME), methyl acetate (MA), methyl propionate (MP), ethyl acetate (EA), methyl butyrate (MB), and combinations thereof. In some embodiments, the electrolyte and the residual solvent additive comprise the same compound.

[0013] In another aspect, a method of preparing an electrode is described. The method includes combining a binder, an electrode active material, water, and a solvent additive to form an electrode film mixture; depositing the electrode film mixture onto a current collector to form an electrode preform; and treating the electrode preform to form an electrode.

[0014] In some embodiments, the method further includes diluting the electrode film mixture with water prior to the step of treating the electrode preform. In some embodiments, the step of treating the electrode preform includes drying the electrode preform. In some embodiments, drying the electrode preform is performed at a temperature of at least about 60°C.

Brief Description of the Drawings

[0015] [Figure 1] It is a schematic diagram showing a multi - lane electrode and compressive stress.

[0016] [Figure 2] This flowchart shows a method for preparing electrodes according to several embodiments.

[0017] [Figure 3] This graph compares the stress curvature values ​​of electrodes manufactured using various solvent additives according to several embodiments, as well as a control electrode.

[0018] [Figure 4A] This is an image of an electrode prepared without the use of solvent additives.

[0019] [Figure 4B] These are images of electrodes prepared using solvent additives according to several embodiments.

[0020] [Figure 5A-1] These are images of multi-lane electrodes according to several embodiments.

[0021] [Figure 5A-2] This is an enlarged image of the multi-lane electrode shown in Figure 5A-1, according to several embodiments.

[0022] [Figure 5B-1] These are images of multi-lane electrodes according to several embodiments.

[0023] [Figure 5B-2] This is an enlarged image of the multi-lane electrode shown in Figure 5B-1, according to several embodiments.

[0024] However, it should be clearly understood that the examples and drawings are for illustrative purposes only and do not necessarily limit the scope of the present invention. [Modes for carrying out the invention]

[0025] While certain preferred embodiments and examples are disclosed below, the subject matter of the invention extends beyond the specifically disclosed embodiments to other alternative embodiments and / or uses, as well as their modifications and equivalents. Therefore, the appended claims are not limited by any of the specific embodiments described below. For example, in any method or process disclosed herein, the operation or behavior of the method or process may be performed in any suitable order, and is not necessarily limited to any specific disclosed order. Various operations may be described as a plurality of separate operations in a manner that may be helpful in understanding a particular embodiment. However, the order of description should not be construed to mean that these operations are order-dependent. Furthermore, the structures, systems, and / or devices described herein may be embodied as integrated components or as separate components. For the purpose of comparing various embodiments, specific aspects and advantages of these embodiments are described. Not all such aspects or advantages are necessarily achieved by a particular embodiment. Therefore, for example, various embodiments may be performed to achieve or optimize one advantage or set of advantages taught herein, without necessarily achieving other aspects or advantages that may be taught or suggested herein.

[0026] Electrodes prepared using water and solvent additives and methods thereof are described. Electrodes formed from an electrode film mixture containing water and solvent additives placed on a current collector can reduce or help reduce compressive stress, thereby preventing or helping to prevent curvature (e.g., warping, bending, induced negative and / or positive curvature) and / or creases (e.g., wrinkles) in the coated and / or exposed portions of the electrode. Methods for preparing such electrodes include the steps of combining water, solvent additives and materials to form an electrode film mixture; coating or placing the electrode film mixture on a current collector to form an electrode preform; and processing the electrode preform (e.g., drying and / or calendering) to form an electrode. Since curvature and creases typically occur during and / or after processing (e.g., drying) of the electrode preform, introducing solvent additives into the electrode film mixture can reduce or help reduce the amount of compressive stress applied to the electrode during and / or after the drying process, enabling a uniform coating of the electrode film mixture on the current collector, thereby achieving improved electrode shape and strength.

[0027] • Method for preparing electrodes using solvent additives A method for preparing an electrode using a solvent additive includes the steps of: forming an electrode film mixture by combining a binder, an electrode active material, water, and a solvent additive; depositing the electrode film mixture onto a current collector to form an electrode preform; and processing the electrode preform (e.g., drying and / or calendering) to form an electrode.

[0028] Figure 2 is a flowchart of a method 200 for preparing electrodes with reduced compressive stress. As shown in Figure 2, in step 210, a binder, electrode active material, water, and solvent additives are mixed to form an electrode film mixture. In step 230, the electrode film mixture is deposited onto a current collector to form an electrode preform. Before depositing the electrode film mixture onto the current collector, in an optional step 220, the electrode film mixture may be diluted with additional water. In step 250, the electrode preform can be further processed (e.g., dried and / or calendered) to form an electrode.

[0029] The electrode film mixture comprises a binder, an electrode active material, water, and a solvent additive. In some embodiments, the electrode film mixture is prepared by dissolving the binder in water to form a precursor mixture, followed by the addition of the electrode active material and solvent additive to the precursor mixture. In some embodiments, a conductive additive may be added to or included in the precursor mixture and / or the electrode film mixture. In some embodiments, the method further includes the step of diluting the electrode film mixture with additional water.

[0030] In some embodiments, the step of processing the electrode preform may include drying and / or calendarizing the electrode preform. In some embodiments, drying is carried out in an oven and / or kiln. In some embodiments, the electrode preform is dried at a drying temperature of approximately those, at least those, at least about those, many of those, or many of those of values ​​in any range between 100°C, 98°C, 96°C, 94°C, 92°C, 90°C, 88°C, 86°C, 84°C, 82°C, 80°C, 78°C, 76°C, 74°C, 72°C, 70°C, 68°C, 66°C, 64°C, 62°C, 60°C, 58°C, 56°C, 54°C, 52°C, 50°C, 48°C, 46°C, 44°C, 42°C, 40°C, 38°C, 36°C, 34°C, 32°C, and 30°C, or any range between those. In some embodiments, the step of processing the electrode preform may include calendarizing the electrode preform. In some embodiments, the electrode preform is dried before calendering.

[0031] In some embodiments, multiple electrode film mixtures are arranged on a current collector in multiple lanes separated by exposed portions to form a multi-lane electrode preform. In some embodiments, the multi-lane electrode preform can be processed to form a multi-lane electrode, which is then separated (e.g., cut) at each exposed portion to form multiple electrodes. The multi-lane electrode includes a foil layer (i.e., a current collector) coated with the electrode film material to form multiple coated lanes (i.e., portions of the foil layer covered with the electrode film material) and multiple exposed lanes (i.e., exposed portions of the foil layer). In some embodiments, the multi-lane electrode may be a double-sided multi-lane electrode including coated lanes on both sides of the foil layer (e.g., top and bottom).

[0032] • Electrode comprising electrode film mixture, electrode preform, and solvent additive. The electrode film mixture described herein comprises a binder, water, an electrode active material, and a solvent additive. Electrodes are formed from the electrode film mixture placed on a current collector and can be processed to form an electrode film. The electrode preform before processing comprises a current collector and the same or essentially the same composition as the electrode film mixture.

[0033] In some embodiments, the electrode film mixture and / or electrode preform further comprises conductive additives. In some embodiments, the conductive additives include carbon black, carbon nanotubes, and combinations thereof.

[0034] In some embodiments, the electrode film mixture and / or electrode preform may be 5% by weight, 4.9% by weight, 4.8% by weight, 4.7% by weight, 4.6% by weight, 4.5% by weight, 4.4% by weight, 4.3% by weight, 4.2% by weight, 4.1% by weight, 4% by weight, 3.9% by weight, 3.8% by weight, 3.7% by weight, 3.6% by weight, 3.5% by weight, 3.4% by weight, 3.3% by weight, 3.2% by weight, 3.1% by weight, 3% by weight, 2.9% by weight, 2.8% by weight, 2.7% by weight, 2.6% by weight, 2.5% by weight, 2.4% by weight, 2.3% by weight, The mixture contains solvent additives in amounts of 2.2% by weight, 2.1% by weight, 2% by weight, 1.9% by weight, 1.8% by weight, 1.7% by weight, 1.6% by weight, 1.5% by weight, 1.4% by weight, 1.3% by weight, 1.2% by weight, 1.1% by weight, 1% by weight, 0.9% by weight, 0.8% by weight, 0.7% by weight, 0.6% by weight, 0.5% by weight, 0.4% by weight, 0.3% by weight, 0.2% by weight, and 0.1% by weight, or any range of values ​​between them, in amounts of about those, at least those, at least about those, more than those, or more than about those. In some embodiments, the electrode film mixture and / or electrode preform contains solvent additives in amounts of at most about 5% by weight. In some embodiments, the electrode film mixture and / or electrode preform contains solvent additives in amounts of at least about 0.1% by weight.

[0035] In some embodiments, the solvent additive includes compounds selected from the group consisting of ethylene carbonate (EC), propylene carbonate (PC), vinylene carbonate (VC), vinylethylene carbonate (VEC), fluoroethylene carbonate (FEC), dimethyl carbonate (DMC), diethyl carbonate (DEC), ethyl methyl carbonate (EMC), 1,3-propensultone (PRS), dimethoxyethane (DME), methyl acetate (MA), methyl propionate (MP), ethyl acetate (EA), methyl butyrate (MB), and combinations thereof.

[0036] In some embodiments, the solvent additive is soluble in water. In some embodiments, the solvent additive is soluble in water at 80°C, 82°C, 84°C, 86°C, 88°C, 90°C, 92°C, 94°C, 96°C, 98°C, 100°C, 102°C, 104°C, 106°C, 108°C, 110°C, 112°C, 114°C, 116°C, 118°C, 120°C, 122°C, 124°C, 126°C, 128℃, 130℃, 132℃, 134℃, 136℃, 138℃, 140℃, 142℃, 144℃, 146℃, 148℃, 150℃, 152℃, 154℃, 156℃, 158℃, 160℃, 162℃, 164℃, 166℃, 168℃, 170℃, 172℃, 174℃, 176℃, 178℃ , having boiling points of 180°C, 182°C, 184°C, 186°C, 188°C, 190°C, 192°C, 194°C, 196°C, 198°C, 200°C, 202°C, 204°C, 206°C, 208°C, 210°C, 212°C, 214°C, 216°C, 218°C, 220°C, 222°C, 224°C, 226°C, 228°C, 230°C, 232°C, 234°C, 236°C, 238°C, 240°C, 242°C, 244°C, 246°C, 248°C and 250°C, or any range in between, about those, at least those, at least about those, many of those, or many of those.

[0037] In some embodiments, the solvent additive is -60°C, -58°C, -56°C, -54°C, -52°C, -50°C, -48°C, -46°C, -44°C, -42°C, -40°C, -38°C, -36°C, -34°C, -32°C, -30°C, -28°C, -26°C, -24°C, -22°C, -20°C, -18°C, -16°C, -14°C, -12°C, -10°C, -8°C, -6°C, -4°C Having melting points of -2°C, 0°C, 2°C, 4°C, 6°C, 8°C, 10°C, 12°C, 14°C, 16°C, 18°C, 20°C, 22°C, 24°C, 26°C, 28°C, 30°C, 32°C, 34°C, 36°C, 38°C, and 40°C, or any range of values ​​in between, approximately those, at least those, at least about those, many of those, or many of those.

[0038] In some embodiments, the electrode film and / or electrode contains residual solvent additives in amounts of 0.1% by weight, 0.2% by weight, 0.3% by weight, 0.4% by weight, 0.5% by weight, 0.6% by weight, 0.7% by weight, 0.8% by weight, 0.9% by weight, 1.0% by weight, 1.1% by weight, 1.2% by weight, 1.3% by weight, 1.4% by weight, 1.5% by weight, 1.6% by weight, 1.7% by weight, 1.8% by weight, 1.9% by weight, and 2% by weight, or any range of values ​​between them, in amounts of at least those, at least about those, more than those, or more than about those. In some embodiments, the electrode film and / or electrode contains residual water in amounts of 0.1% by weight, 0.2% by weight, 0.3% by weight, 0.4% by weight, 0.5% by weight, 0.6% by weight, 0.7% by weight, 0.8% by weight, 0.9% by weight, 1.0% by weight, 1.1% by weight, 1.2% by weight, 1.3% by weight, 1.4% by weight, 1.5% by weight, 1.6% by weight, 1.7% by weight, 1.8% by weight, 1.9% by weight, and 2% by weight, or any range of values ​​between them, at least those, at least about those, at most those, or at most about those amounts.

[0039] As a result of uneven binder shrinkage during drying, residual stress can be present in the electrodes, potentially causing them to bend. The stress curvature value can be used to determine the degree of stress or deformation of the electrodes. The stress curvature value is the Young's modulus (E) of the substrate. s ) and substrate thickness (h s Compressive stress (σ) at the electrode, Poisson's ratio (v) of the substrate. s ), and electrode thickness (h f It can be calculated by the Stoney equation, which incorporates the product of ). The stress curvature value can be characterized by the following (K) or (1 / R), where R refers to the radius of curvature.

number

[0040] In some embodiments, the electrodes are at most about 1.75 m -1 , 1.7m -1 , 1.65m -1, 1.6m -1 , 1.55m -1 , 1.5m -1 , 1.45m -1 , 1.4m -1 , 1.35m -1 , 1.3m -1 , 1.25m -1 , 1.2m -1 , 1.15m -1 , 1.1m -1 , 1.05m -1 , 1m -1 , 0.95m -1 , 0.9m -1 , 0.85m -1 , 0.8m -1 , 0.75m -1 , 0.7m -1 , 0.65m -1 , 0.6m -1 , 0.55m -1 , 0.5m -1 , 0.45m -1 , 0.4m -1 , 0.35m -1 , 0.3m -1 and 0.25m -1 , or have stress curvature values of any range of values between them.

[0041] In some embodiments, the electrode film has a thickness of 100μm, 102μm, 104μm, 106μm, 108μm, 110μm, 112μm, 114μm, 116μm, 118μm, 120μm, 122μm, 124μm, 126μm, 128μm, 130μm, 132μm, 134μm, 136μm, 138μm, 140μm, 142μm, 144μm, 146μm, 148μm, 150μm, 152μm, 154μm, 156μm, 158μm, 160μm, 162μm, 164μm, 166μm, 168μm, 170μm, 172μm, 174μm, 176μm, 178μm, 180μm, 182μm, 184μm, 186μm, 188μm, 190μm, 192μm, 194μm, 196μm, 198μm and 200μm, or any range of values between them, of about them, at least them, at least about them, at most them, or at most about them.

[0042] Electrode active materials (e.g., positive electrode active material, negative electrode active material) can be used in electrode film mixtures, electrode films, electrode preforms, and / or electrodes for energy storage devices.

[0043] In some embodiments, the electrode active material is the positive electrode active material. In some embodiments, the positive electrode active material is selected from at least one of materials comprising metal oxides, metal sulfides, sulfur-carbon composites, lithium metal oxides, and sulfur. In some embodiments, the positive electrode active material is lithium iron phosphate (i.e., LiFePO4 or "LFP"), lithium iron manganese phosphate (e.g., LiMn 0.6 Fe 0.4 PO4 or "LMFP"), lithium nickel manganese cobalt oxide (i.e., LiNi x Mn y Co 1-x-y O2 or "NMC"), lithium nickel cobalt aluminum oxide (i.e., LiNi x Co y Al z The cathode active material is selected from O2 (or "NCA"), lithium manganese oxide ("LMO"), lithium nickel manganese oxide ("LNMO"), lithium carbon nickel manganese oxide ("LCNMO"), lithium cobalt oxide ("LCO"), or a combination thereof. In some embodiments, the cathode active material includes at least two of LFP, LMFP, NMC, NCA, LMO, LNMO, LCO, and combinations thereof. In some embodiments, the cathode active material is an iron phosphate-based active material. In some embodiments, the iron phosphate-based active material is LiFePO4 (i.e., "lithium iron phosphate" and "LFP") and LiMn 1-x Fe x PO4 (i.e., "lithium iron manganese phosphate" and "LMFP") (e.g., LiMn 0.6 Fe 0.4 PO4 or LiMn 0.8 Fe 0.2It includes PO4). In some embodiments, the iron phosphate-based active material includes LFP. In some embodiments, the iron phosphate-based active material includes LMFP. In some embodiments, the iron phosphate-based active material includes LFP and / or LMFP.

[0044] In some embodiments, the electrode active material is the anode active material. In some embodiments, the anode active material may include, for example, an insertion material (e.g., carbon, graphite, and / or graphene), an alloying / dealloying material (e.g., silicon, silicon oxide, tin, and / or tin oxide), a metallic alloy or compound (e.g., Si-Al and / or Si-Sn), lithium titanate ("LTO") and / or conversion material (e.g., manganese oxide, molybdenum oxide, nickel oxide, and / or copper oxide). The anode active material may be used alone or mixed together to form a multiphase material (e.g., Si-C, Sn-C, SiOx-C, SnOx-C, Si-Sn, Si-SiOx, Sn-SnOx, Si-SiOx-C, Sn-SnOx-C, Si-Sn-C, SiOx-SnOx-C, Si-SiOx-Sn, Sn-SiOx-SnOx). The negative electrode active material includes common natural graphite, synthetic or artificial graphite, surface-modified graphite, spherical graphite, flake graphite, and blends or combinations of these types of graphite, metal elements and their compounds, as well as metal-C composites for the negative electrode. In some embodiments, the negative electrode active material includes one or more of carbon, hard carbon, graphite, common natural graphite, synthetic or artificial graphite, silicon, Si-C, tin, tin oxide, lithium titanate, and combinations thereof.

[0045] In some embodiments, the electrode film mixture and / or electrode film contains about those amounts, at least those amounts, or at least about those amounts of electrode active material in the range of 70% by weight, 75% by weight, 80% by weight, 85% by weight, 86% by weight, 87% by weight, 88% by weight, 89% by weight, 90% by weight, 91% by weight, 92% by weight, 93% by weight, 94% by weight, 95% by weight, 96% by weight, 97% by weight, 98% by weight, 98.5% by weight, 99% by weight, 99.5% by weight, 99.8% by weight, or 99.9% by weight, or any range between those amounts.

[0046] In some embodiments, the electrode film mixture and / or electrode film comprises a carbon material configured to reversibly intercalate lithium ions. In some embodiments, the carbon intercalating lithium is selected from graphitic carbon, graphite, hard carbon, soft carbon, and combinations thereof. For example, the electrode film of an electrode may include a binder material, one or more of graphitic carbon, graphite, graphene-containing carbon, hard carbon, and soft carbon, as well as a conductivity-enhancing material. In some embodiments, the electrode is mixed with lithium metal and / or lithium ions. In some embodiments, the electrode film mixture and / or electrode film comprises a carbon material in an amount of about 20% by weight, 15% by weight, 10% by weight, 9% by weight, 8% by weight, 7% by weight, 6% by weight, 5% by weight, 4% by weight, 3% by weight, 2% by weight, 1% by weight, or any range between those values, in a total amount of about those, more than those, or more than about those.

[0047] In some embodiments, the electrode film mixture and / or electrode film includes a conductive additive. In some embodiments, the conductive additive may include a conductive carbon additive such as carbon black. In some embodiments, the conductive additive may include a conductive carbon additive. In some embodiments, the conductive carbon additive includes carbon black, carbon nanotubes, such as single-walled carbon nanotubes (SWCNTs) and multi-walled carbon nanotubes (MWCNTs). In some embodiments, the electrode film mixture and / or electrode film includes the conductive additive in an amount of about 10% by weight, 9% by weight, 8% by weight, 7% by weight, 6% by weight, 5% by weight, 4% by weight, 3% by weight, 2% by weight, 1% by weight, 0.5% by weight, 0.25% by weight, 0.1% by weight, or any range between those values, in a total amount of about those, at most those, or at most about those. In some embodiments, each conductive additive is present in amounts of 10% by weight, 9% by weight, 8% by weight, 7% by weight, 6% by weight, 5% by weight, 4% by weight, 3% by weight, 2% by weight, 1% by weight, 0.5% by weight, 0.25% by weight, 0.1% by weight, or any range between these values, in amounts of, at most, or at most about these amounts of the electrode film mixture and / or electrode film. In some embodiments, the conductive additive is carbon black.

[0048] In some embodiments, the electrode film mixture and / or electrode film comprises a binder or binder material. In some embodiments, the binder may include polytetrafluoroethylene (PTFE), polyolefins, polyalkylenes, polyethers, styrene-butadiene, polysiloxane and polysiloxane copolymers, branched polyethers, polyvinyl ethers, carboxymethylcellulose (CMC), polyacrylates, copolymers thereof, and / or combinations thereof. In some embodiments, the polyolefin may include polyethylene (PE), polypropylene (PP), polyvinylidene fluoride (PVDF), copolymers thereof, and / or combinations thereof. For example, the binder may include polyvinyl chloride, poly(phenylene oxide) (PPO), polyethylene-block-poly(ethylene glycol), poly(ethylene oxide) (PEO), poly(phenylene oxide) (PPO), polyethylene-block-poly(ethylene glycol), polydimethylsiloxane (PDMS), polydimethylsiloxane-coalkylmethylsiloxane, copolymers thereof, and / or combinations thereof. In some embodiments, the binder may include thermoplastics. In some embodiments, the binder may include sodium carboxymethylcellulose (NaCMC), lithium carboxymethylcellulose (LiCMC), styrene-butadiene rubber (SBR), poly(acrylic acid) (PAA), polyacrylonitrile (PAN), polyvinyl alcohol (PVA), and combinations thereof. In some embodiments, the electrode film mixture and / or electrode film contains a binder in an amount of 1% by weight, 2% by weight, 3% by weight, 4% by weight, 5% by weight, 6% by weight, 7% by weight, 8% by weight, 9% by weight, 10% by weight, or any range between those amounts, in amounts of about those, more than those, or more than about those amounts.

[0049] • Electrodes and energy storage devices An energy storage system or device includes a positive electrode (i.e., cathode), a negative electrode (i.e., anode), a separator placed between them, and an electrolyte placed within a housing. The electrodes include an electrode film mixture placed on a current collector. In some embodiments, the current collector may include a metallic material such as aluminum, nickel, copper, or a combination thereof. In some embodiments, the current collector may include a pure metal. In some embodiments, the current collector may include a metallized polymer film or a metal-coated polymer film. In some embodiments, the polymer may include polyethylene terephthalate (PET), biaxially oriented polypropylene (BOPP), or a combination thereof. In some embodiments, the metal coating may include aluminum. In some embodiments, coating the final electrode film mixture includes forming a uniform electrode film mixture coating. In some embodiments, the current collector may include thicknesses of approximately 200 μm, 100 μm, 50 μm, 40 μm, 30 μm, 20 μm, 15 μm, 10 μm, 5 μm, or any range in between.

[0050] In some embodiments, the electrode may be a wet electrode. A “wet” electrode, a “wet process” electrode, or a slurry electrode is an electrode prepared by at least one step comprising a slurry, electrode film mixture, or electrode preform of an active material, binder, and optionally additives, even if a subsequent drying step removes moisture and / or solvent from the electrode or electrode film mixture. Thus, a wet electrode, a wet electrode film mixture, or a wet electrode preform contains at least one or more processing solvents, processing solvent residues, and / or processing solvent impurities. In some embodiments, a wet electrode, a wet electrode film mixture, or a wet electrode preform formed with solvent additives contains additional residual solvents compared to a wet electrode, a wet electrode film mixture, or a wet electrode preform formed without solvent additives. Such wet-processed electrodes are in contrast to electrode films prepared by dry electrode manufacturing processes that form dry electrode films without the use of solvents or substantially without them, thereby allowing active layers or electrode films formed from dry electrode film mixtures using dry manufacturing processes to be free from or substantially free from any processing additives such as solvents and the resulting residual solvents.

[0051] In some embodiments, the electrode is a double-sided electrode. In some embodiments, the double-sided electrode includes two electrode films. In some embodiments, the double-sided electrode may include a current collector, an upper electrode film, and a lower electrode film. In some embodiments, each of the two electrode films may have any suitable shape, size, and thickness.

[0052] In some embodiments, the energy storage device includes a separator, a negative electrode, a positive electrode, an electrolyte, and a housing, wherein the electrolyte, separator, negative electrode, and positive electrode are arranged within the housing, and the separator is positioned between the negative electrode and the positive electrode. In some embodiments, the energy storage device is formed by arranging the electrolyte, separator, negative electrode, and positive electrode described herein within a housing, with the separator positioned between the negative electrode and the positive electrode.

[0053] The electrode assembly includes a positive electrode, a negative electrode, and a separator located between the negative and positive electrodes. In some embodiments, the electrode assembly is a wound electrode (i.e., a rolled electrode) assembly (e.g., a jelly roll). In some embodiments, the energy storage device is selected from the group consisting of cylindrical energy storage devices, laminated prism energy storage devices, and helically wound prism energy storage devices.

[0054] Normalized circularity can be used to determine and / or associate relatively weak core spots (e.g., spots that may cause electrode buckling) in wound electrode assemblies. The normalized circularity of a non-ideal helix is ​​defined as the minimum ratio between the non-ideal (actual) geometric shape and the ideal geometric shape at each point, according to the following formula:

number

[0055] The non-ideal (actual) spiral shape is given by measured Cartesian and polar coordinates (x,y,θ,r), while the ideal spiral shape is derived from the Archimedean spiral according to r = αθ + β. The geometry of a spiral (ideal or non-ideal) can be characterized by its curvature (K), such as the following polar curvature parameterization.

number

[0056] In some embodiments, the electrode assembly is 0.7, 0.705, 0.71, 0.715, 0.72, 0.725, 0.73, 0.735, 0.74, 0.745, 0.75, 0.76, 0.77, 0.78, 0.79, 0.8, 0.805, 0.81, 0.815, 0.82, 0.825, 0.83, 0.835, 0.84, 0.845 , 0.85, 0.86, 0.87, 0.88, 0.89, 0.90, 0.91, 0.92, 0.93, 0.94, 0.95, 0.96, 0.97, 0.98, 0.99, 1, 1.05, 1.1, 1.15, 1.2, or any range of values ​​between them, including approximately those, at least those, or at least approximately those normalized circularity values.

[0057] The electrodes disclosed herein may be used in energy storage devices. In some embodiments, the energy storage device includes a separator, a negative electrode, a positive electrode, an electrolyte, and a housing, wherein the electrolyte, separator, negative electrode, and positive electrode are arranged within the housing, and the separator is positioned between the negative electrode and the positive electrode. In some embodiments, the energy storage device is formed by arranging the electrolyte, separator, negative electrode, and positive electrode described herein within the housing, with the separator positioned between the negative electrode and the positive electrode. In some embodiments, the energy storage device includes a negative electrode positioned between two positive electrodes. In some embodiments, the negative electrode and / or positive electrode include a molded electrode film. In some embodiments, the energy storage device is a lithium-ion battery. In some embodiments, the energy storage device may be a battery, a capacitor, a capacitor-battery hybrid, a fuel cell, or a combination thereof. In some embodiments, the energy storage system or energy storage device may be used in electromobility. In some embodiments, the energy storage device may be used in vehicles including hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), and / or electric vehicles (EVs). In some embodiments, the energy storage device used in vehicles including hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), and / or electric vehicles (EVs) reduces greenhouse gas emissions.

[0058] In some embodiments, the energy storage device is charged with a suitable lithium-containing electrolyte. For example, the energy storage device may contain a lithium salt and a solvent such as a non-aqueous solvent or an organic solvent. Generally, the lithium salt contains a redox-stable anion. In some embodiments, the anion may be monovalent. In some embodiments, the lithium salt can be selected from lithium hexafluorophosphate (LiPF6), lithium bis(trifluoromethanesulfonyl)imide (LiFSI), lithium tetrafluoroborate (LiBF4), lithium perchlorate (LiClO4), lithium bis(trifluoromethanesulfonyl)imide (LiN(SO2CF3)2), lithium trifluoromethanesulfonate (LiSO3CF3), lithium bis(oxalato)borate (LiB(C2O4)2), lithium bis(fluorosulfonyl)imide (LiN(SO2F)2), lithium difluoro(oxalato)borate (LiC2BF2O4), and combinations thereof. In some embodiments, the electrolyte may include a quaternary ammonium cation and an anion selected from the group consisting of hexafluorophosphate, tetrafluoroborate, and iodide. In some embodiments, the salt concentration may be about 0.1 mol / L(M) to about 5 M, about 0.2 M to about 3 M, or about 0.3 M to about 2 M. In further embodiments, the salt concentration of the electrolyte may be about 0.7 M to about 2 M. In certain embodiments, the salt concentration of the electrolyte may be about 0.2 M, about 0.3 M, about 0.4 M, about 0.5 M, about 0.6 M, about 0.7 M, about 0.8 M, about 0.9 M, about 1 M, about 1.1 M, about 1.2 M, 1.3 M, 1.4 M, 1.5 M, or values ​​in between.

[0059] The electrolyte comprises a liquid solvent (i.e., the solvent, the electrolyte solvent). The solvent does not need to dissolve all components of the electrolyte, nor does it need to completely dissolve any component. In further embodiments, the solvent may be an organic solvent. In some embodiments, the solvent may contain one or more functional groups selected from dioxathiolanes (e.g., 1,3,2-dioxathiolane-2,2-dioxide (i.e., "DTD")), carbonates, ethers, and / or esters. In some embodiments, the solvent may contain a carbonate. In further embodiments, the carbonate can be selected from cyclic carbonates, such as ethylene carbonate (EC), propylene carbonate (PC), vinylethylene carbonate (VEC), vinylene carbonate (VC), fluoroethylene carbonate (FEC), and combinations thereof, or from acyclic carbonates, such as dimethyl carbonate (DMC), diethyl carbonate (DEC), ethyl methyl carbonate (EMC), 1,3-propensultone (PRS), and combinations thereof. In some embodiments, the solvent can include an ester. In some embodiments, the ester can be selected from methyl acetate (MA), methyl propionate (MP), ethyl acetate (EA), methyl butyrate (MB), and combinations thereof. In some embodiments, the solvent may include EC, PC, VEC, VC, FEC, DMC, DEC, EMC, MA, MP, EA, MB, and combinations thereof. In some embodiments, the solvent may include EC, DMC, DEC, EMC, MA, and combinations thereof. In some embodiments, the solvent may include EC:DMC:EMC ratios of 10-30:0-90:0-70.

[0060] In some embodiments, one or more solvents can be used in concentrations of approximately these, at least these, or at least about these, of 30% by weight, 35% by weight, 40% by weight, 45% by weight, 50% by weight, 55% by weight, 60% by weight, 65% by weight, 70% by weight, 75% by weight, 80% by weight, 85% by weight, or 90% by weight, or any range of values ​​in between. In some embodiments, the solvent is used as an additive in the electrolyte system (i.e., an electrolyte additive) in concentrations of 0.1% by weight, 0.2% by weight, 0.3% by weight, 0.4% by weight, 0.5% by weight, 0.6% by weight, 0.7% by weight, 0.8% by weight, 0.9% by weight, 1% by weight, 1.1% by weight, 1.2% by weight, 1.3% by weight, 1.4% by weight, 1.5% by weight, 1.6% by weight, 1.7% by weight, 1.8% by weight, 1.9% by weight It can be used in concentrations of approximately these, at most these, or at most these, of values ​​in any range between these, such as 0.1 to 10% by weight, 1 to 6% by weight, 2.2% by weight, 2.3% by weight, 2.4% by weight, 2.5% by weight, 2.6% by weight, 2.7% by weight, 2.8% by weight, 2.9% by weight, 3% by weight, 4% by weight, 5% by weight, 6% by weight, 7% by weight, 8% by weight, 9% by weight, or 10% by weight, or any range between these. For example, in some embodiments, the amount of additive in the electrolyte is in the range of or about one of the following ranges: 0.1 to 10% by weight, 1 to 6% by weight, 2 to 5% by weight, 0.1 to 6% by weight, 2 to 8% by weight, 2 to 3% by weight, or 1 to 4% by weight.

[0061] In some embodiments, the electrolyte and the solvent additive and / or residual solvent additive comprise the same compound. In some embodiments, the electrolyte solvent and the solvent additive and / or residual solvent additive comprise the same compound. In some embodiments, the electrolyte additive and the solvent additive and / or residual solvent additive comprise the same compound.

[0062] In some embodiments, the energy storage device is fabricated such that one electrode (e.g., the negative electrode) is larger than and overhangs the other electrode (e.g., the positive electrode). One electrode may overhang the other in the winding direction and / or non-winding direction of the electrode assembly. Such electrode overhangs can avoid yield losses. In some embodiments, where the separator and the molded electrode film (e.g., the positive electrode film) do not overlap, or substantially do not overlap, and / or do not mix, it is easier to identify the boundary of the molded electrode film, and therefore the ability to form a counter electrode (e.g., the negative electrode) with an overhang is improved. [Examples]

[0063] Exemplary embodiments of the present disclosure, including processes, materials, and / or resulting products, are described in the following examples.

[0064] • Example 1 - Stress curvature Figure 3 is a graph showing the stress curvature values ​​of electrodes manufactured using various solvent additives and electrodes manufactured without solvent additives. As shown in Figure 3, electrodes manufactured using solvent additives containing 1% by weight of vinylene carbonate (VC), ethyl methyl carbonate (EMC), dimethyl carbonate (DMC), fluoroethylene carbonate (FEC), and ethylene carbonate (EC), respectively, showed reduced stress curvature values ​​compared to the baseline electrode manufactured without solvent additives.

[0065] • Example 2 - Comparison of electrodes with and without solvent additives Figure 4A is an image of an electrode prepared without solvent additives, resulting in an electrode exhibiting negative curvature induced by compressive stress. Figure 4B is an image of an electrode prepared with 1 wt% ethylene carbonate (EC) additive, resulting in an electrode exhibiting a reduction in negative curvature induced by compressive stress.

[0066] • Example 3 - Comparison of multi-lane electrodes with and without solvent additives Figure 5A-1 is an image of a multi-lane electrode formed from an electrode film mixture containing water and no solvent additives. Figure 5A-2 is a magnified image of the multi-lane electrode. As shown in Figures 5A-1 and 5A-2, the multi-lane electrode includes coated lanes 525A-1, 525A-2 and exposed lanes 550A-1, 550A-2, with the exposed lanes 550A-1, 550A-2 showing folds between the coated lanes 525A-1, 525A-2. Curvature and folds resulting from negative curvature induced by compressive stress are visible in Figure 5A-2.

[0067] Figure 5B-1 is an image of a multi-lane electrode formed from an electrode film mixture containing water and 1 wt% ethylene carbonate (EC) additive. Figure 5B-2 is a magnified image of the multi-lane electrode. As shown in Figures 5B-1 and 5B-2, the multi-lane electrode includes coated lanes 525B-1, 525B-2 and exposed lanes 550B-1, 550B-2, and the exposed lanes 550A-1, 550A-2, 550B-1, 550B-2 between the coated lanes 525B-1, 525B-2 exhibit a foil free from curvature and folds between the electrodes due to the use of the ethylene carbonate (EC) additive, reducing negative curvature due to compressive stress.

[0068] While specific embodiments of the present invention have been described, these embodiments are presented as examples only and are not intended to limit the scope of this disclosure. In fact, the novel methods and systems described herein can be embodied in a variety of other forms. Furthermore, various omissions, substitutions, and modifications of the systems and methods described herein can be made without departing from the spirit of this disclosure. The appended claims and their equivalents are intended to encompass forms or modifications that are contained within the scope and spirit of this disclosure. Accordingly, the scope of the present invention is defined solely by reference to the appended claims.

[0069] Any features, materials, properties, or group described in relation to a particular aspect, embodiment, or example should be understood to be applicable to any other aspect, embodiment, or example described in this section or elsewhere in this specification, insofar as it does not conflict with the description thereof. All features disclosed herein (including the appended claims, abstract, and drawings), and / or all steps of any method or process disclosed herein, may be combined in any combination, except for any combination in which at least some of such features and / or steps are mutually exclusive. The protection is not limited to the details of any of the aforementioned embodiments. The protection extends to any novel one or any novel combination of features disclosed herein (including the appended claims, abstract, and drawings), or any novel one or any novel combination of any step of any method or process disclosed herein.

[0070] Furthermore, certain features described in this disclosure in the context of separate embodiments may also be implemented in combination in a single embodiment. Conversely, various features described in the context of a single embodiment may also be implemented individually or in any suitable partial combination in multiple embodiments. Furthermore, features may be described above as acting in a particular combination, but one or more features from a claimed combination may be removed from the combination in some cases, and the combination may be claimed as a partial combination or a variation of a partial combination.

[0071] Furthermore, while operations may be shown in the drawings or described herein in a specific order, such operations do not need to be performed in the specific order shown or in a sequential order, or not all operations need to be performed, in order to achieve the desired result. Other operations not shown or described may be incorporated into the exemplary methods and processes. For example, one or more additional operations may be performed before, after, concurrently with, or between any of the described operations. Furthermore, operations may be rearranged or reordered in other embodiments. Those skilled in the art will understand that in some embodiments, the actual steps performed in the illustrated and / or disclosed processes may differ from those shown in the drawings. Depending on the embodiment, certain steps among the steps described above may be omitted, and other steps may be added. Furthermore, the features and attributes of the particular embodiments disclosed above may be combined in different ways to form additional embodiments, all of which are within the scope of this disclosure. Also, the separation of various system components in the embodiments described above should not be understood as requiring such separation in all embodiments, and the described components and systems may generally be integrated together in a single product or packaged in multiple products. For example, any of the components of the energy storage system described herein may be provided separately or as an integrated unit (for example, packaged together or mounted together) to form the energy storage system.

[0072] For the purposes of this disclosure, certain aspects, advantages, and novel features are described herein. Not all of such advantages can necessarily be achieved according to any particular embodiment. Therefore, for example, a person skilled in the art will recognize that this disclosure can be embodied or implemented to achieve one or more advantages as taught herein, without necessarily achieving other advantages that can be taught or suggested herein.

[0073] Conditional language, such as "can," "could," "might," or "may," is generally intended to convey that a particular embodiment includes a particular feature, element, and / or step, but other embodiments do not, unless otherwise specified or understood in the context in which it is used. Therefore, such conditional language is generally not intended to suggest that a feature, element, and / or step is required in any way in one or more embodiments, or that one or more embodiments necessarily include logic for determining, with or without user input or prompting, whether a feature, element, and / or step is included in or should be performed in any particular embodiment.

[0074] Conjunctional phrases such as "at least one of X, Y, and Z" are generally understood in contexts where they indicate that an item, term, etc., may be X, Y, or Z, unless otherwise specified. Therefore, such conjunctional phrases are not generally intended to imply that a particular embodiment requires the presence of at least one X, at least one Y, and at least one Z.

[0075] As used herein, the terms "approximately," "about," "generally," and "substantially" still refer to values, quantities, or characteristics close to the described value, quantity, or characteristic that still perform the desired function or achieve the desired result. For example, the terms "approximately," "about," "generally," and "substantially" may refer to quantities less than 10%, less than 5%, less than 1%, less than 0.1%, and less than 0.01% of the described quantity, depending on the desired function or desired result.

[0076] The scope of this disclosure is not intended to be limited by any specific disclosure of preferred embodiments in this section or elsewhere in this specification, but may be defined by the claims, as presented in this section or elsewhere in this specification, or as presented in the future. The language of the claims should be interpreted broadly in the language used in the claims and not limited to the examples described herein or during examination of the application, and the examples should be interpreted as non-exclusive.

Claims

1. Binder and, Water and, Electrode active material and, Solvent additives and, Includes, An electrode film mixture containing at most about 5% by weight of the solvent additive.

2. The electrode film mixture according to claim 1, wherein the solvent additive comprises a compound selected from the group consisting of ethylene carbonate (EC), propylene carbonate (PC), vinylene carbonate (VC), vinylethylene carbonate (VEC), fluoroethylene carbonate (FEC), dimethyl carbonate (DMC), diethyl carbonate (DEC), ethyl methyl carbonate (EMC), 1,3-propensultone (PRS), dimethoxyethane (DME), methyl acetate (MA), methyl propionate (MP), ethyl acetate (EA), methyl butyrate (MB), and combinations thereof.

3. The electrode film mixture according to claim 1, wherein the solvent additive has a boiling point temperature of at least about 80°C.

4. The electrode film mixture according to claim 1, wherein the solvent additive is soluble in water.

5. The electrode film mixture according to claim 1, wherein the electrode film mixture contains at least about 0.1% by weight of the solvent additive.

6. The electrode film mixture according to claim 1, wherein the electrode film mixture contains at least about 0.1% by weight of water.

7. The electrode film mixture according to claim 1, further comprising a conductive additive.

8. An electrode preform comprising the electrode film mixture according to claim 1, disposed on a current collector.

9. An electrode film, wherein the electrode film is binder, electrode active material, Residual water, and An electrode film containing residual solvent additives, Current collector and, Equipped with, An electrode in which the electrode film is placed on the current collector.

10. The electrode according to claim 9, comprising at most about 0.1% by weight of the residual solvent additive.

11. The electrode according to claim 9, comprising at most about 0.1% by weight of the residual water.

12. At most about 1.5m －１ The electrode according to claim 9, including a stress curvature value.

13. The electrode according to claim 9, wherein the electrode film has a thickness of at least about 120 μm.

14. The electrode according to claim 9, The second electrode and A separator disposed between the electrode described in claim 9 and the second electrode, Electrolytes, The casing and Equipped with, An energy storage device comprising the electrode described in claim 9, the second electrode, the separator, and the electrolyte, arranged within the housing.

15. The energy storage device according to claim 14, wherein the electrolyte comprises a compound selected from the group consisting of ethylene carbonate (EC), propylene carbonate (PC), vinylene carbonate (VC), vinylethylene carbonate (VEC), fluoroethylene carbonate (FEC), dimethyl carbonate (DMC), diethyl carbonate (DEC), ethyl methyl carbonate (EMC), 1,3-propensultone (PRS), dimethoxyethane (DME), methyl acetate (MA), methyl propionate (MP), ethyl acetate (EA), methyl butyrate (MB), and combinations thereof.

16. The energy storage device according to claim 14, wherein the electrolyte and the residual solvent additive contain the same compound.

17. A method for preparing electrodes, The steps include: forming an electrode film mixture by combining a binder, electrode active material, water, and solvent additives; The steps include: depositing the electrode film mixture onto a current collector to form an electrode preform; The steps include processing the electrode preform to form an electrode, Methods that include...

18. The method according to claim 17, further comprising the step of diluting the electrode film mixture with water before the step of processing the electrode preform.

19. The method according to claim 17, wherein the step of processing the electrode preform includes drying the electrode preform.

20. The method according to claim 19, wherein the drying of the electrode preform is carried out at a temperature of at least about 60°C.

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