Electrode manufacturing technique

Abstract

The present application relates to an electrode comprising a redox active material and a low dimensional carbon material. At least about 70% of the electrode surface comprises at least one layer comprising a low dimensional carbon material. The electrode comprises up to about 45% by weight of the low dimensional carbon material based on the total weight of the low dimensional carbon material and the redox active material in the electrode.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to electrodes comprising a redox-active material and a low-dimensional carbon material, and methods of forming such electrodes. BACKGROUND

[0002] Electrodes are a critical component of batteries. However, many commonly used electrodes and methods of manufacturing them suffer from a range of problems.

[0003] For example, standard electrode manufacturing processes use N-methyl-2-pyrrolidone (NMP) as a solvent. The solvent typically needs to be evaporated at a late stage of the manufacturing process, which increases time and energy costs. Furthermore, NMP is toxic, so when NMP is used as a solvent, additional steps / equipment are required to recover and contain the evaporated NMP. NMP is also flammable, which presents a safety hazard.

[0004] Additionally, many conventional electrodes contain a binder (e.g. a polymeric binder), which increases the mass and volume of the electrode. If the binder chosen is not redox-active or conductive, the capacity of the electrode can be limited.

[0005] Standard electrode manufacturing processes typically require high temperatures to bind the electrode components into a mechanically stable electrode. This makes the overall process energy intensive and there is a risk of thermal damage to the electrode materials.

[0006] It would be desirable to produce an electrode and an electrode formation method that reduces, for example, the need for solvents and high temperatures, and / or increases capacity and / or reduces charge transfer resistance. Furthermore, one or more of the deficiencies in known electrodes and / or electrode formation methods should also be eliminated, mitigated and / or improved, whether these deficiencies are identified herein or otherwise. SUMMARY

[0007] According to a first aspect of the disclosure, there is provided an electrode comprising a redox-active material and a low-dimensional carbon material, wherein: at least about 70% of the electrode surface comprises at least one layer comprising a low-dimensional carbon material; and the electrode comprises at most about 45% by weight of the low-dimensional carbon material, based on the total weight of the low-dimensional carbon material and the redox-active material in the electrode.

[0008] According to a second aspect, there is provided a battery comprising one or more electrodes as described above.

[0009] According to a third aspect, there is provided a method of forming an electrode, wherein the method comprises: preparing an agglomerate comprising a redox-active material and at least one layer comprising a low-dimensional carbon material; and The agglomerates are pressed to form an electrode, wherein: at least about 70% of the electrode surface comprises at least one layer comprising a low-dimensional carbon material; and the electrode comprises at most about 45 wt% of the low-dimensional carbon material, based on the total weight of the low-dimensional carbon material and the redox-active material in the electrode.

[0010] According to a fourth aspect, there is provided a device suitable for carrying out the method described herein.

[0011] Further optional and preferred features of the devices and methods of the application will be set forth in the detailed description that follows, and in part will be apparent from the description that follows, or can be learned by practice of the application.

[0012] Definitions

[0013] The terms used herein are defined as follows. If any term is not expressly defined herein or elsewhere, it is intended to be interpreted in accordance with the standard meaning of that term in the art. The standard meaning can be referred to the definitions in general knowledge of the art (e.g. standard textbooks). For example, chemical terms can be interpreted in accordance with the IUPAC Gold Book, 3.0.1 edition.

[0014] The term "at least one" is synonymous with "one or more", e.g. one, two, three, four, five, six or more.

[0015] As used herein, the terms "about", "approximately" or "substantially" and the like, generally encompass or refer to a range of values that one of skill in the art would consider equivalent to the value being described (e.g. having the same function or result, and / or being implemented in a substantially similar way). Where appropriate, the term "about" when used to describe a numerical value, can mean (in order of preference) a value deviating by 10%, 5%, 2%, 1% or 0% from that value.

[0016] The term "low-dimensional carbon material" is a term in the art. For the avoidance of any doubt, a low-dimensional carbon material refers to a material comprising carbon, the particles of which are at the nanometer scale in at least one spatial dimension, e.g. about 0.1 to 1000 nanometers, about 0.5 to 500 nanometers, about 1 to 250 nanometers or about 5 to 100 nanometers. The low-dimensional carbon material can comprise other chemical elements in addition to carbon, e.g. oxygen.

[0017] The term "zero-dimensional carbon material" as used herein refers to a carbon material comprising particles at the nanometer scale in three spatial dimensions, e.g. buckminsterfullerene and carbon black.

[0018] The term "one-dimensional carbon material" as used herein refers to a carbon material comprising particles at the nanometer scale in only two spatial dimensions, e.g. carbon nanofibers, carbon fibers and carbon nanotubes. Such materials can comprise acicular, rod-like or tubular particles.

[0019] As used in this article, the term "two-dimensional carbon material" refers to carbon materials containing particles that are at the nanoscale in only one spatial dimension, such as graphene oxide, graphene, porous graphene, graphite oxide, graphyne, and graphenylene. Such materials can contain sheet-like or flattened particles.

[0020] The term "redox-active material" is a term used in this art. To avoid any ambiguity, a redox-active material refers to a material capable of undergoing redox processes. During a redox process, the oxidation state of a component in a redox-active material changes, for example, through the gain or loss of electrons or atomic transfer. For example, lithium cobalt oxide is a redox-active material in which the oxidation state of cobalt can change (e.g., through lithium intercalation / deintercalation).

[0021] The term "cathode material" is a term used in the art. To avoid any ambiguity, a cathode material is a redox-active material suitable for use as a cathode, such as containing atoms / ions (e.g., lithium or sodium) that can be reversibly inserted or extracted from the cathode material.

[0022] The term "anodic material" is a term used in the art. To avoid any ambiguity, an anode material is a redox-active material suitable for use as an anode, such as containing a cavity into which atoms / ions (such as lithium or sodium) can reversibly intercalate.

[0023] If the amount of the first component in the electrode is expressed as a weight percentage relative to the amount of the second component in the electrode, and based on the total weight of the first and second components in the electrode, it can be calculated as follows: .

[0024] For example, the electrode may contain 4.5g of low-dimensional carbon material and 5.5g of redox-active material. Therefore, based on the total weight of the low-dimensional carbon material and redox-active material in the electrode, the electrode contains 45% by weight of low-dimensional carbon material.

[0025] To avoid any ambiguity, this parameter is independent of the amount of other components in the electrode. For example, the electrode described in the previous paragraph may contain no other components. Alternatively, it may contain 10g of other components. In both cases, based on the total weight of the low-dimensional carbon material and the redox active material in the electrode, the electrode contains 45% by weight of the low-dimensional carbon material.

[0026] Alternatively, if the amount of a particular component in the electrode is expressed as a percentage of weight based on the total weight of the electrode, it can be calculated as follows: .

[0027] If the percentage of the electrode surface is described as containing a layer, it can be calculated as follows: .

[0028] For example, the electrode surface may contain a low-dimensional carbon material layer with an outer surface area of ​​7 cm². The total outer surface area of ​​the electrode (including the surface area occupied by this layer) may be 10 cm². Therefore, 70% of the electrode surface comprises this low-dimensional carbon material layer.

[0029] The term “layer” as used in this article refers to a material / aggregate in which one spatial dimension is significantly smaller than each of the other two spatial dimensions, for example, smaller by 60%, 70%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99%.

[0030] When referring to the "thickness" of a layer, it can be understood as referring to the minimum spatial dimension of that layer. For example, if the dimensions of a layer are 10 cm × 10 cm × 1 cm, then the thickness of that layer is 1 cm.

[0031] As used in this paper, the term "interconnected layer" refers to layers that are permanently or temporarily connected to each other. Such connections can occur, for example, through covalent bonds, ionic bonds, hydrogen bonds, dipole-dipole interactions, van der Waals interactions, mechanical bonding, hydrophobic / hydrophilic interactions, etc. These connections may also result from layer compression.

[0032] When the word "at least" is used with a ratio, it should be interpreted as the first number in the ratio being the number shown or greater than the number shown, and / or the second number in the ratio being the number shown or correspondingly less than the number shown. For example, describing an electrode as containing a first layer and a second layer, with a thickness ratio of "at least about 0.1:1," means that such a ratio can have values ​​such as 0.1:1, 0.2:1, or 0.1:0.9.

[0033] The above statement also applies when the word "at most" is used to describe a ratio.

[0034] As used in this article, the term "porous and / or gas-permeable" means that gas can pass through a material. This includes materials that may require external intervention (e.g., the application of pressure) to allow gas to pass through.

[0035] Electrode capacity represents the number of electrons that can be transferred to or transferred from the electrode during charging and discharging. Capacity can be expressed as an absolute value (unit: Ampere). h), per unit mass (unit is A) h g -1) or per unit volume (unit is A) h m -3 ).

[0036] As used in this article, the term "binder" refers to a substance that is typically added to an electrode to bind its various components together.

[0037] As used herein, the term "redox activity" in the context of adhesives refers to an adhesive capable of undergoing redox processes (as defined above) under normal electrode / cell conditions.

[0038] As used in this article, the term "electronic conductivity" in the context of adhesives refers to the ability of an adhesive to allow an electric current to flow between itself. For example, the electronic conductivity of an electronically conductive adhesive can be at least about 1 Sk. cm -1 Conversely, the term "electronic insulation" as used in this paper, in the context of adhesives, refers to an adhesive's high resistance to the passage of electric current. For example, the electronic conductivity of an electronically insulating adhesive is at most about 0.5 S. cm -1 .

[0039] The term “enhanced adhesion” used in this article, in the context of adhesives, refers to the ability of an adhesive to improve / promote the adhesion within an electrode by being present inside the electrode (i.e., the ability of the electrode to adhere / remain together and bond / remain attached to the current collector without disintegrating due to mechanical action).

[0040] The term “enhanced flexibility” as used in this article, in the context of adhesives, refers to the ability of an adhesive to improve / promote the flexibility (i.e., the ability of an electrode to bend / deform without breaking) of an electrode by being present inside it.

[0041] As used herein, the term "aggregate" refers to a collection of materials that are not necessarily bound together; for example, an aggregate can be in powder form. For completeness, an aggregate may include materials that are bound together.

[0042] The term “average particle size” appropriately refers to the index mean and is determined using dynamic light scattering (e.g., using Malvern Zetasizer Nano ZS90), as per ISO 22412:2017.

[0043] The terms “average particle size” and “average particle length” refer to the number mean values ​​measured by scanning electron microscopy (e.g., Zeiss Merlin-Analytical), transmission electron microscopy (e.g., JEOL 3000F), and X-ray computed tomography (e.g., Zeiss Xradia 810 Ultra).

[0044] Some materials have primary and secondary particle sizes. As used herein, the term "primary particle size" refers to the particle size of the material produced prior to its use in the method of forming an electrode. The term "secondary particle size" as used herein refers to the particle size of the material after it has been used in the method of forming an electrode. For example, due to material compression, the secondary particle size is typically larger than the primary particle size.

[0045] In the context of current collectors, the terms “surface treated” and “surface treatment” as used in this article refer to coating / depositing a substance (e.g., carbon or metal) on the surface of the current collector (e.g., the first and / or second surface). Attached Figure Description

[0046] Figure 1 According to the schematic diagram of the electrodes disclosed herein; Figure 2 Scanning electron microscope (SEM) images of the surfaces of the low-dimensional carbon material layers of the two electrodes according to this disclosure; Figure 3 Based on the SEM and energy-dispersive spectroscopy (EDS) images of the electrode cross-section of this disclosure; Figure 4 SEM image of a cross-section of another electrode according to this disclosure; Figure 5 Comparison of the constant current charge-discharge curves of the electrode of this disclosure with those of conventional electrodes; Figure 6 A comparison of electrochemical impedance spectroscopy (EIS) measurements of the electrode and conventional electrodes according to this disclosure; and Figure 7 : A schematic diagram of the electrode manufacturing method according to this disclosure. Detailed Implementation

[0047] According to a first aspect of this disclosure, an electrode is provided, the electrode comprising a redox-active material and a low-dimensional carbon material, wherein: At least approximately 70% of the electrode surface contains at least one layer comprising low-dimensional carbon material; and Based on the total weight of the low-dimensional carbon material and redox active material in the electrode, the electrode contains up to approximately 45% by weight of low-dimensional carbon material.

[0048] It has been found that at least one layer containing low-dimensional carbon material can immobilize redox-active materials in place, exhibiting an encapsulation / sandwich effect. This reduces the need for non-redox-active and / or electronic insulating materials (e.g., redox inert and / or electronic insulating adhesives) in the electrode, while maintaining good mechanical stability and performance.

[0049] The at least one layer containing low-dimensional carbon material also serves as a highly conductive and ionicly conductive interface (e.g., between the redox active material and the current collector, and / or between the redox active material and the electrolyte), exhibiting low charge transfer resistance. While not wanting to be bound by theory, it is believed that this low resistance results in high capacity and allows for rapid charging of the electrodes.

[0050] Limiting the proportion of low-dimensional carbon materials in the electrode (e.g., to approximately 45% by weight based on the total weight of low-dimensional carbon materials and redox active materials in the electrode) can increase the electrode capacity relative to electrodes with a higher proportion of low-dimensional carbon materials. This is because low-dimensional carbon materials contribute less to energy storage and ion storage compared to redox active materials.

[0051] The electrode surface may contain at least 75% of a layer comprising a low-dimensional carbon material, optionally at least 80%, optionally at least 85%, optionally at least 90%, optionally at least 95%, optionally at least 99%.

[0052] A higher surface coverage is advantageous because it allows the highly conductive low-dimensional carbon material to have more contact with other components of the battery, such as current collectors and / or electrolytes.

[0053] Based on the total weight of the low-dimensional carbon material and redox active material in the electrode, the electrode may include: At least about 0.1% by weight of low-dimensional carbon material, optionally, at least about 0.5% by weight, optionally, at least about 1% by weight, optionally, at least about 1.5% by weight, optionally, at least about 2% by weight, optionally, at least about 3% by weight; and / or Up to about 40% by weight of low-dimensional carbon materials, optionally, up to about 30% by weight, optionally, up to about 20% by weight, optionally, up to about 10% by weight, optionally, up to about 8% by weight, optionally, up to about 6% by weight, optionally, up to about 5% by weight; and / or About 0.1 to 40% by weight of low-dimensional carbon materials, optionally, about 0.1 to 30% by weight, optionally, about 0.5 to 20% by weight, optionally, about 1 to 10% by weight, optionally, about 1.5 to 8% by weight, optionally, about 2 to 6% by weight, optionally, about 3 to 5% by weight, optionally, about 4% by weight.

[0054] Low-dimensional carbon materials can be substantially porous and / or permeable to gases (such as air or argon). It has been found that low-dimensional carbon materials with these properties enable electrodes to be compressed to higher densities, which can, for example, benefit mechanical stability and volumetric capacity. Without being bound by theory, it is believed that this higher density is due to the easier escape of gas molecules that would otherwise be trapped during electrode fabrication.

[0055] Low-dimensional carbon materials can be zero-dimensional, one-dimensional, or two-dimensional carbon materials, and optionally can be sheet-like, flat, tubular, or needle-like carbon materials.

[0056] For example, it has been found that one-dimensional carbon materials can form interconnect networks with good mechanical stability. Similarly, two-dimensional carbon materials can form interconnect layers, which also have good mechanical stability.

[0057] Low-dimensional carbon materials can be selected from graphene oxide, graphene, porous graphene, graphene oxide, carbon nanofibers, carbon fibers, carbon nanotubes, graphyne and graphenylene.

[0058] Low-dimensional carbon materials can be selected from: (a) Graphene oxide, graphene, porous graphene and graphene oxide, optionally having an average particle size of about 0.01 to 10 µm; (b) Carbon nanotubes, optionally having an average particle length of 0.01 to 5 µm and / or an average particle size of about 1 to 500 nm; (c) Carbon nanofibers, optionally having an average particle length of about 1 to 200 µm and / or an average particle size of about 0.05 to 10 µm; or (d) Carbon fibers, optionally having an average particle length of about 5 to 500 µm and / or an average particle size of about 1 to 20 µm.

[0059] Electrodes containing low-dimensional carbon materials (having these particle sizes) have been found to have particularly good mechanical strength. For example, without being bound by theory, it is believed that carbon nanotubes, carbon nanofibers, and carbon fibers with the particle lengths and diameters given in (b) to (d) above form highly interconnected networks.

[0060] The electrode may contain at least two layers comprising low-dimensional carbon materials.

[0061] The electrode may include a first layer, a second layer, and a third layer; wherein: The first layer contains low-dimensional carbon materials; The second layer contains redox-active materials; The third layer contains low-dimensional carbon materials; and The second layer is located between the first and third layers.

[0062] The manufacture of this electrode is particularly simple; it is formed by pressing the first, second, and third layers together in a top-to-bottom order.

[0063] The thickness ratio of the first layer to the second layer can be: At least approximately 5×1 :1, optionally, at least approximately 1×1 :1, optionally, at least approximately 1×1 :1, optionally, at least approximately 1×1 ³:1, optionally, at least about 0.01:1, optionally, at least about 0.1:1; and / or Up to approximately 30:1, optionally; up to approximately 10:1, optionally; up to approximately 5:1, optionally; up to approximately 3:1, optionally; up to approximately 2:1, optionally; up to approximately 1:1; and / or Approximately 5×10 -6 :1 to 30:1, optional, approximately 1×10 -5 :1 to 10:1, optional, approximately 1×10 -4 :1 to 5:1, optional, approximately 1×10 -3 :1 to 3:1, optionally, about 0.01:1 to 2:1, optionally, about 0.1:1 to 1:1.

[0064] The thickness of the third layer can differ from the thickness of the first layer by approximately 10%, optionally by approximately 8%, optionally by approximately 6%, optionally by approximately 4%, or optionally by approximately 2%.

[0065] The thickness of at least one layer containing low-dimensional carbon material can be: At least about 1 nm, optionally, at least about 10 nm, optionally, at least about 20 nm, optionally, at least about 50 nm; and / or Up to approximately 100,000 nm, optionally, up to approximately 50,000 nm, optionally, up to approximately 10,000 nm, optionally, up to approximately 5,000 nm; and / or Approximately 1 to 100,000 nm, optionally, approximately 1 to 50,000 nm, optionally, approximately 1 to 10,000 nm, optionally, approximately 1 to 5,000 nm.

[0066] It has been found that layers with thicknesses in these ranges can encapsulate electrodes particularly effectively, providing good mechanical stability while also ensuring good electronic and ionic conductivity.

[0067] The thickness of the second layer (if any) can be: At least about 1µm, optionally, at least about 5µm, optionally, at least about 10µm, optionally at least about 20µm, optionally at least about 50µm; and / or Up to about 10,000 µm, optionally, up to about 7,500 µm, optionally, up to about 5,000 µm, optionally up to about 2,500 µm, optionally up to about 1,000 µm; and / or Approximately 1 to 10,000 µm, optionally, approximately 5 to 7,500 µm, optionally, approximately 10 to 5,000 µm, optionally, approximately 20 to 2,500 µm, optionally, approximately 50 to 1,000 µm.

[0068] It has been found that the greater the thickness of the second layer (containing redox-active materials), the higher the energy storage. However, with increasing thickness, conductivity and ion diffusivity decrease, so the increase in energy storage is not linearly proportional to layer thickness. It has been found that the aforementioned thickness range can well balance these factors.

[0069] The redox active material can be a cathode material, optionally selected from: (a) Metal oxides, optionally, layered metal oxides (e.g., lithium cobalt oxides, lithium nickel manganese cobalt oxides, lithium manganese nickel oxides (e.g., lithium-rich Li) 1.2 Mn 0.6 Ni 0.2 O2) and lithium nickel cobalt aluminum oxide), spinel (e.g. lithium manganese oxide) and disordered rock salt (e.g. Li) 1.25 Nb 0.25 Mn 0.5 O2); preferably lithium nickel manganese cobalt oxide (e.g., LiNi). x Mn y Co z O2, x+y+z = 1); and (b) Polyanionic compounds (e.g., lithium iron phosphate).

[0070] The average primary particle size of the cathode material can be about 1 to 500 nm, and / or the average secondary particle size can be about 1 to 300 µm.

[0071] The redox active material can be an anode material, optionally selected from graphite, silicon, silicon oxide, Li4Ti5O. 12 Hard carbon and soft carbon.

[0072] The average particle size of the anode material can be from about 0.01 to 300 µm.

[0073] The electrode capacity can be at least about 10 mA. h g -1 Optionally, at least about 200 mA h g -1 Optionally, at least about 400 mA h g -1 Optionally, at least about 600 mA h g -1 Optionally, at least approximately 800 mA h g -1 Optionally, at least about 1000 mA h g -1 .

[0074] For batteries in small portable devices such as smartphones, electrodes with higher capacity per unit mass are particularly desirable because they have higher energy density, which in turn provides longer battery life.

[0075] The resistance of the electrodes is at most approximately 1000 Ω. cm 2 Optionally, up to approximately 200 Ω cm 2 Optionally, up to approximately 150 Ω cm 2 Optionally, up to approximately 100 Ω cm 2 Optionally, up to approximately 50 Ω cm 2 Optionally, up to approximately 1 Ω cm 2 .

[0076] Electrodes with lower resistance can store more (useful) energy and charge faster, which is very useful for batteries in devices that require fast charging, such as smartphones and electric vehicles.

[0077] Based on the total weight of the electrode, the electrode may contain up to about 5% by weight of adhesive, optionally up to about 4% by weight of adhesive, optionally up to about 3% by weight of adhesive, optionally up to about 2% by weight of adhesive, optionally up to about 1% by weight of adhesive, optionally up to about 0.5% by weight of adhesive, optionally up to about 0.1% by weight of adhesive, optionally up to about 0.01% by weight of adhesive.

[0078] Based on the total weight of the electrode, the electrode may contain up to about 8% by weight of redox inert and / or electronic insulating binder, optionally up to about 7% by weight, optionally up to about 6% by weight, optionally up to about 5% by weight, optionally up to about 4% by weight, optionally up to about 3% by weight, optionally up to about 2% by weight, optionally up to about 1% by weight, optionally up to about 0.5% by weight, optionally up to about 0.1% by weight, optionally up to about 0.01% by weight.

[0079] In some embodiments, the electrode does not contain a redox inert binder and / or does not contain an electronic insulating binder.

[0080] In some embodiments, the electrodes do not contain an adhesive (e.g., a polymeric adhesive, such as polyvinylidene fluoride or polytetrafluoroethylene).

[0081] In some embodiments, the electrode comprises one or more redox-active and / or electronically conductive adhesives. Optionally, the one or more redox-active and / or electronically conductive adhesives are independently selected from polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), carboxymethyl cellulose (CMC), styrene-butadiene rubber (SBR), polyacrylic acid (PAA), vinyl adhesives, cellulose-based adhesives, polyaniline-based adhesives, polypyrrole-based adhesives, polylactic acid-based adhesives, and chitosan-based adhesives.

[0082] In some embodiments, the electrode comprises one or more adhesives that enhance adhesion and / or flexibility. Optionally, the one or more adhesives that enhance adhesion and / or flexibility are independently selected from polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), carboxymethyl cellulose (CMC), styrene-butadiene rubber (SBR), polyacrylic acid (PAA), vinyl adhesives, polylactic acid adhesives, glycol adhesives, and methacrylic acid adhesives.

[0083] Since adhesives are generally not redox active, they do not promote the transfer of electrons from or to the electrode. Therefore, electrodes containing very little or no electronic insulating adhesive exhibit higher capacity.

[0084] The electrode can be disposed near the current collector. The current collector may contain a metal (optionally, aluminum, copper, or stainless steel), wherein: (a) The redox-active material is the cathode material, and the current collector contains aluminum; or (b) The redox active material is the anode material, and the current collector contains copper.

[0085] The current collector may be surface-treated, and optionally carbon (optionally low-dimensional carbon materials) and / or metal (optionally silver and / or manganese) may be used.

[0086] The thickness of the current collector can range from approximately 3 nanometers to 1 millimeter.

[0087] According to a second aspect of this disclosure, a battery is provided that includes one or more electrodes as described above.

[0088] The battery can be a pouch battery, a cylindrical battery, a prismatic battery, or a button battery.

[0089] According to a third aspect, a method for forming an electrode is provided, wherein the method includes: Preparation of aggregates comprising a redox-active material and at least one layer comprising a low-dimensional carbon material; and The aggregates are pressed to form electrodes, wherein: At least approximately 70% of the electrode surface contains at least one layer comprising low-dimensional carbon material; and Based on the total weight of the low-dimensional carbon material and redox active material in the electrode, the electrode contains up to approximately 45% by weight of low-dimensional carbon material.

[0090] It has been found that pressing the aggregates to form electrodes, wherein at least one layer comprising low-dimensional carbon material firmly encapsulates / encapsulates the redox active material, as described in the first aspect above.

[0091] At least about 75% of the electrode surface may contain at least one layer comprising low-dimensional carbon material, optionally at least about 80%, optionally at least about 85%, optionally at least about 90%, optionally at least about 95%, optionally at least about 99%.

[0092] The electrode may contain up to about 40% by weight of low-dimensional carbon material, optionally up to about 35% by weight of low-dimensional carbon material, optionally up to about 30% by weight of low-dimensional carbon material, optionally up to about 25% by weight of low-dimensional carbon material, optionally up to about 20% by weight of low-dimensional carbon material, optionally up to about 15% by weight of low-dimensional carbon material, optionally up to about 10% by weight of low-dimensional carbon material.

[0093] The preparation of the aggregates may include: Prepare a first layer, wherein the first layer comprises a low-dimensional carbon material. A second layer is placed on top of the first layer, wherein the second layer comprises a redox-active material, and A third layer is placed on top of the second layer, wherein the third layer contains low-dimensional carbon material.

[0094] The suppressed agglomerates may include suppressing the first, second, and third layers.

[0095] As discussed above in the first aspect, forming electrodes in this way is a particularly straightforward and simple process because, for example, the first, second, and third layers can simply be stacked together in sequence and then pressed from above.

[0096] The pressing can be performed at the following temperatures: Up to approximately 250°C, optionally; up to approximately 200°C, optionally; up to approximately 150°C, optionally; up to approximately 100°C, optionally; up to approximately 50°C, optionally; up to approximately 40°C, optionally; up to approximately 30°C; and / or Approximately -50 to 250°C, optional; approximately -30 to 200°C, optional; approximately -20 to 150°C, optional; approximately -10 to 100°C, optional; approximately 0 to 50°C, optional; approximately 10 to 40°C, optional; approximately 20 to 30°C.

[0097] Limiting the pressing temperature can reduce the energy requirements of the electrode formation process. The method described herein is particularly advantageous in this respect because it can be performed without any external heating, for example, at room temperature.

[0098] The pressing may include calendering; optionally, at a pressure of about 0.01 to 2 m. s -1 The calendering process is carried out at a certain speed, where "calendering speed" refers to the speed at which the material passes through the calendering equipment. In industrial environments, calendering is a particularly effective way to suppress agglomerates because it can apply approximately constant pressure to raw materials containing agglomerates (e.g., on a conveyor belt).

[0099] The calendering may include asymmetric calendering, optionally wherein the first roll operates at a speed of approximately 0.1 to 0.5 m. s -1 The second roller operates at a speed of approximately 0.8 to 1.3 m. s -1 .

[0100] At least one layer containing low-dimensional carbon material may be substantially porous and / or permeable to gases (e.g., air or argon).

[0101] The method may also include venting a gas (e.g., air or argon) from the redox-active material through one or more layers of at least one layer containing a low-dimensional carbon material. As described in the first aspect above, venting the gas through at least one layer containing a low-dimensional carbon material produces a higher density electrode.

[0102] The compression may include using the following pressures: At least about 0.5 MPa, optionally at least about 1 MPa, optionally at least about 3 MPa, optionally at least about 5 MPa, optionally at least about 7 MPa, optionally at least about 9 MPa, optionally at least about 10 MPa; and / or Up to approximately 1000 MPa, optionally up to approximately 800 MPa, optionally up to approximately 600 MPa, optionally up to approximately 400 MPa, optionally up to approximately 300 MPa, optionally up to approximately 200 MPa, optionally up to approximately 100 MPa; and / or Approximately 0.5 to 1000 MPa, optionally approximately 1 to 800 MPa, optionally approximately 3 to 600 MPa, optionally approximately 5 to 400 MPa, optionally approximately 7 to 300 MPa, optionally approximately 9 to 200 MPa, optionally approximately 10 to 100 MPa.

[0103] It has been found that pressures within these ranges can produce electrodes with exceptionally good mechanical stability. Without being bound by theory, it is believed that such pressures will induce strong binding interactions between low-dimensional carbon materials and redox-active materials.

[0104] After pressing, the thickness of at least one layer containing low-dimensional carbon material (e.g., the first and third layers) can be: At least approximately 50nm; and / or Up to approximately 30,000 nm, optionally, up to approximately 20,000 nm, optionally, up to approximately 10,000 nm, optionally, up to approximately 5,000 nm; and / or Approximately 50 to 30,000 nm, optionally, approximately 50 to 20,000 nm, optionally, approximately 50 to 10,000 nm, optionally, approximately 50 to 5,000 nm.

[0105] After the pressing process, the thickness of the second layer (if any) can be: At least about 1µm, optionally, at least about 2µm, optionally, at least about 3µm, optionally, at least about 4µm, optionally, at least about 5µm; and / or Up to about 10,000 µm, optionally, up to about 7,500 µm, optionally, up to about 5,000 µm, optionally, up to about 2,500 µm, optionally, up to about 1,000 µm; and / or Approximately 1 to 10,000 µm, optionally, approximately 2 to 7,500 µm, optionally, approximately 3 to 5,000 µm, optionally, approximately 4 to 2,500 µm, optionally, approximately 5 to 1,000 µm.

[0106] In some embodiments, the method does not involve the use of a solvent (e.g., N-methyl-2-pyrrolidone or water). Using a solvent in the electrode formation process is disadvantageous because additional process steps / equipment are required to evaporate and remove the solvent. For toxic solvents such as N-methyl-2-pyrrolidone, additional process steps / equipment are also required to safely collect the evaporated solvent.

[0107] In some embodiments, the method does not include the use of redox inert adhesives and / or does not include the use of electronic insulating adhesives.

[0108] In some implementations, the method does not involve the use of adhesives (e.g., polymeric adhesives such as polyvinylidene fluoride or polytetrafluoroethylene).

[0109] In some embodiments, the method includes using one or more redox-active and / or electronically conductive adhesives. Optionally, the one or more redox-active and / or electronically conductive adhesives are independently selected from polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), carboxymethyl cellulose (CMC), styrene-butadiene rubber (SBR), polyacrylic acid (PAA), vinyl adhesives, cellulose-based adhesives, polyaniline-based adhesives, polypyrrole-based adhesives, polylactic acid-based adhesives, and chitosan-based adhesives.

[0110] In some embodiments, the method includes using one or more adhesives that enhance adhesion and / or flexibility. Optionally, the one or more adhesives that enhance adhesion and / or flexibility are independently selected from polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), carboxymethyl cellulose (CMC), styrene-butadiene rubber (SBR), polyacrylic acid (PAA), vinyl adhesives, polylactic acid-based adhesives, glycol-based adhesives, and methacrylic acid-based adhesives.

[0111] The method may also include placing one or more layers (e.g., a first layer) of at least one layer containing low-dimensional carbon material on the current collector, optionally wherein the current collector contains a metal (e.g., aluminum, copper, or stainless steel).

[0112] The current collector may include a first surface and a second surface, and the method may include placing one or more layers (e.g., the first layer) of at least one layer comprising a low-dimensional carbon material on each of the first and second surfaces. It should be understood that this method will produce a current collector having an electrode according to the present disclosure on each surface.

[0113] The method may include surface treating the current collector (optionally prior to placing one or more layers of at least one layer containing low-dimensional carbon material), optionally with carbon (optionally with low-dimensional carbon material) and / or metal (optionally with silver and / or manganese).

[0114] The electrodes can be formed using the methods described above, or have already been formed using the methods described above.

[0115] According to a fourth aspect, an apparatus suitable for carrying out the method described herein is provided. The apparatus preferably includes a powder supply device, a powder layer forming device, and a powder layer compression device. The apparatus may include: (a) One or more powder feeders, optionally including a vibration mechanism (e.g., an electromagnetic vibration mechanism); and / or (b) conveyor belt; and / or (c) A compression device, optionally including one or more calendering rolls.

[0116] The device may also include an imaging apparatus for online observation, optionally including a camera. Optionally, the device may also include components for processing and analyzing the images generated by the imaging apparatus. This device is particularly effective because it allows for online imaging, analysis, and quality control during electrode manufacturing.

[0117] Optionally, the device may also include online electronic open-loop or closed-loop control for processing the electrodes. Optionally, the device is configured to simulate mechanical compression. Optionally, the device may also be configured to predict optimal electrode porosity, electrode microstructure, battery performance, and / or manufacturing parameters based on images generated by an imaging device.

[0118] Example

[0119] Example 1: Preparation of an electrode

[0120] The electrode formation process according to this disclosure is as follows: a first layer (low-dimensional carbon material) is prepared, a second layer (redox active material) is placed on the first layer, a third layer (low-dimensional carbon material) is placed on the second layer, and then the three layers are pressed. Figure 1 This is a schematic diagram of this type of electrode.

[0121] The following are exemplary electrode compositions.

[0122]

[0123] Example 2: Structural analysis of the electrode using a scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS)

[0124] The electrodes were cut into small pieces (approximately 1 cm x 0.5 cm) and then attached to a titanium blade. Then, Ar was used. + Ion etching prepares the cross-section of the electrode for SEM and EDS analysis.

[0125] Figure 2 SEM images of the surface of the low-dimensional carbon material layer of the two electrodes according to Example 1. Figure 2(a) shows the carbon fiber layer of electrode 1. Figure 2 (b) shows the graphite oxide layer of electrode 2.

[0126] Figure 3 (a) to (d) are SEM images of the cross-section of electrode 2. Figure 3 (a) shows the top layer of graphene oxide and the middle layer of LiNi. 0.6 Mn 0.2 Co 0.2 O2 layer. Figure 3 (b) shows the middle LiNi 0.6 Mn 0.2 Co 0.2 The O2 layer and the bottom graphite oxide layer. Figure 3 (c) is Figure 3 (a) is an enlarged view showing the two-dimensional structure of the graphite oxide layer. Figure 3 (d) is Figure 3 (b) is an enlarged view showing LiNi 0.6 Mn 0.2 Co 0.2 Microstructure of the O2 layer. Figure 3 (c) and Figure 3 The close packing in (d) indicates that the electrodes have good structural stability. It is particularly noteworthy that there is no binder present.

[0127] Figure 3 (e) and (f) are EDS images of the cross-section of electrode 2. Figure 3 (e) shows the location of carbon atoms, which are only present in the top and bottom layers of the electrode. Figure 3 (f) shows the location of manganese ions, which are present only in the middle layer. These images show that the electrode has a distinct three-layer structure.

[0128] Figure 4 SEM image of the cross-section of electrode 1. Figure 4 (a) shows the bottom carbon fiber layer, indicating that it is an interconnect network with good mechanical stability. Figure 4 (b) shows the middle LiNi 0.6 Mn 0.2 Co 0.2 O2 layer. Figure 4 (c) shows the carbon fiber layer and LiNi 0.6 Mn 0.2 Co 0.2 The interface between the O2 layers indicates the individual LiNi 0.6 Mn 0.2 Co 0.2 The O2 particles are encapsulated in carbon fiber. This indicates that they possess strong adhesive properties and good mechanical stability.

[0129] Example 3: Electrochemical testing of the electrode

[0130] Electrochemical performance tests were performed on electrode 6 (according to Example 1 above) and lithium metal anode at a temperature of approximately 25°C.

[0131] Figure 5 (a) Electrode 6 (labeled "layered electrode") was compared with a conventional electrode of the same type (a uniform mixture of carbon and silicon materials) at 250 mA. g -1 Constant current charge-discharge curves under charge-discharge current. The results show that at this current, the capacity of electrode 6 is 57% higher than that of the conventional electrode.

[0132] Figure 5 (b) Similarly, the measured capacity of electrode 6 and the conventional electrode was compared at increasing charge and discharge currents. This shows that the capacity of electrode 6 is significantly higher than that of the conventional electrode at all test currents. Therefore, electrode 6 is well-suited for fast charging. Figure 5 (b) A comparison was also made at 250 mA. g -1 The capacity was measured after 100 charge-discharge cycles under current, and the results showed that electrode 6 also exhibited a higher capacity than the conventional electrode over long cycle periods.

[0133] Example 4: Measurement of the electrode resistance using electrochemical impedance spectroscopy (EIS)

[0134] Electrodes are formed according to Example 1 described above. These electrodes are then assembled into a battery having a button cell, pouch cell, or prismatic cell structure. The battery includes a working electrode (formed according to Example 1) and a reference electrode (e.g., lithium foil), separated by a polymer separator (e.g., polyethylene) or a glass fiber separator. The battery is sealed and tested at approximately 25°C using EIS (frequency range 0.01 to 10). 6 Tested at Hz.

[0135] Figure 6 EIS measurements of electrode 6 (labeled "layered electrode") and similar conventional electrodes were compared in a coin cell using a lithium metal reference electrode and a polyethylene / polypropylene separator. Figure 6 (a) shows the EIS measurement results of the battery in its initial state. Figure 6 (b) shows the EIS measurement results after the battery was charged. Figure 6 (c) shows the EIS measurement results after battery discharge. In these figures, the diameter of the approximate semicircle represents the charge transfer resistance of the electrode. The measurement results show that the charge transfer resistance of electrode 6 is consistently about 2.7 to 3 times smaller than that of the conventional electrode in the initial state, after battery charging, and after battery discharge. While not wanting to be bound by theory, this may partially explain...Figure 5 The excellent energy storage performance and long charge-discharge cycle performance shown are illustrated.

[0136] Example 5: Method for manufacturing an electrode

[0137] Figure 7 A method for manufacturing electrodes according to Embodiment 1 described above is illustrated. According to the illustrated method, a powder feeder (e.g., which may include an electromagnetic vibration mechanism) is used to sequentially spread layers of low-dimensional carbon material, redox-active material, and more low-dimensional carbon material onto a metal foil moving along a conveyor belt. These successive layers can be stacked on top of each other, and then pressed together using calendering rollers in a pressing or compression step. The force applied by the rollers bonds the layers together to form an electrode material sheet. Simultaneously, gas is expelled during the compression step. This may be air or an inert gas, such as a rare gas like argon (e.g., if operating in a controlled atmosphere). The resulting electrode material sheet can be appropriately cut into smaller pieces to form electrodes of various sizes.

[0138] According to this disclosure, this method of preparing electrodes does not require solvents, binders, or high temperatures.

[0139] Examples of machines for performing this method may include powder feeders, conveyor belts, and a series of calendering rolls. Preferably, the machine includes at least two calendering rolls. Preferably, the machine includes at least three powder feeders. The powder feeders may include a vibration mechanism, which may be an electromagnetic vibration mechanism. The powder feeders may be gravity feeders. The machine may also include one or more covers, or may be located within a sealed unit to contain the metal powder and restrict the powder from mixing with or transferring into the ambient atmosphere. The sealed unit of the machine may be equipped with an inert gas supply line.

[0140] In this embodiment, the pressure applied by the calendering roll during the pressing step is about 0.5 to 1000 MPa, more preferably about 10 to 100 MPa.

[0141] It has been found that pressures within these ranges can produce electrodes with exceptionally good mechanical stability. Without being bound by theory, it is believed that such pressures will induce strong binding interactions between low-dimensional carbon materials and redox-active materials.

[0142] This method and machine can be extended to roll-to-roll continuous production processes. Using larger equipment, a suitable feed width can be 1 to 2 meters, with a productivity of 0.01 to 2 m / s. -1 .

[0143]

[0144] This disclosure also includes the following provisions, which may be asserted: 1. An electrode comprising a redox active material and a low-dimensional carbon material, wherein: At least approximately 70% of the electrode surface contains at least one layer comprising low-dimensional carbon material; and Based on the total weight of the low-dimensional carbon material and the redox active material in the electrode, the electrode contains up to about 45% by weight of low-dimensional carbon material.

[0145] 2. The electrode as described in Clause 1, wherein at least about 75% of the electrode surface comprises at least one layer comprising a low-dimensional carbon material, optionally at least about 80%, optionally at least about 85%, optionally at least about 90%, optionally at least about 95%, optionally at least about 99%.

[0146] 3. The electrode as described in any of the foregoing clauses, wherein, based on the total weight of the low-dimensional carbon material and the redox-active material in the electrode, the electrode comprises: At least about 0.1% by weight of low-dimensional carbon material, optionally, at least about 0.5% by weight, optionally, at least about 1% by weight, optionally, at least about 1.5% by weight, optionally, at least about 2% by weight, optionally, at least about 3% by weight; and / or Up to about 40% by weight of low-dimensional carbon materials, optionally, up to about 30% by weight, optionally, up to about 20% by weight, optionally, up to about 10% by weight, optionally, up to about 8% by weight, optionally, up to about 6% by weight, optionally, up to about 5% by weight; and / or About 0.1 to 40% by weight of low-dimensional carbon materials, optionally, about 0.1 to 30% by weight, optionally, about 0.5 to 20% by weight, optionally, about 1 to 10% by weight, optionally, about 1.5 to 8% by weight, optionally, about 2 to 6% by weight, optionally, about 3 to 5% by weight, optionally, about 4% by weight.

[0147] 4. The electrode as described in any of the foregoing clauses, wherein the low-dimensional carbon material is substantially porous and / or permeable to gases (e.g., air or argon).

[0148] 5. The electrode as described in any of the foregoing clauses, wherein the low-dimensional carbon material is a zero-dimensional, one-dimensional, or two-dimensional carbon material, optionally a sheet-like, flat, tubular, or needle-like carbon material.

[0149] 6. The electrode as described in any of the foregoing clauses, wherein the low-dimensional carbon material is selected from graphene oxide, graphene, porous graphene, graphene oxide, carbon nanofibers, carbon fibers, carbon nanotubes, graphyne and grapheneene.

[0150] 7. The electrode as described in any of the foregoing clauses, wherein the low-dimensional carbon material is selected from: (a) Graphene oxide, graphene, porous graphene and graphene oxide, optionally having an average particle size of about 0.01 to 10 µm; (b) Carbon nanotubes, optionally having an average particle length of 0.01 to 5 µm and / or an average particle size of about 1 to 500 nm; (c) Carbon nanofibers, optionally having an average particle length of about 1 to 200 µm and / or an average particle size of about 0.05 to 10 µm; or (d) Carbon fibers, optionally having an average particle length of about 5 to 500 µm and / or an average particle size of about 1 to 20 µm.

[0151] 8. An electrode as described in any of the foregoing clauses, comprising at least two layers containing low-dimensional carbon material.

[0152] 9. The electrode as described in Clause 8, comprising a first layer, a second layer, and a third layer; wherein: The first layer contains low-dimensional carbon materials; The second layer contains redox-active materials; The third layer contains low-dimensional carbon materials; and The second layer is located between the first and third layers.

[0153] 10. The electrode as described in Clause 9, wherein the thickness ratio of the first layer and the second layer is: At least approximately 5×1 :1, optionally, at least approximately 1×1 :1, optionally, at least approximately 1×1 :1, optionally, at least approximately 1×1 ³:1, optionally, at least about 0.01:1, optionally, at least about 0.1:1; and / or Up to approximately 30:1, optionally; up to approximately 10:1, optionally; up to approximately 5:1, optionally; up to approximately 3:1, optionally; up to approximately 2:1, optionally; up to approximately 1:1; and / or Approximately 5×10 -6 :1 to 30:1, optional, approximately 1×10 -5 :1 to 10:1, optional, approximately 1×10 -4 :1 to 5:1, optional, approximately 1×10 -3 :1 to 3:1, optionally, about 0.01:1 to 2:1, optionally, about 0.1:1 to 1:1.

[0154] 11. The electrode as described in Clause 9 or 10, wherein the thickness of the third layer may differ from the thickness of the first layer by about 10%, optionally by about 8%, optionally by about 6%, optionally by about 4%, optionally by about 2%.

[0155] 12. The electrode as described in any of the foregoing clauses, wherein the thickness of the at least one layer comprising a low-dimensional carbon material is: At least about 1 nm, optionally, at least about 10 nm, optionally, at least about 20 nm, optionally, at least about 50 nm; and / or Up to approximately 100,000 nm, optionally, up to approximately 50,000 nm, optionally, up to approximately 10,000 nm, optionally, up to approximately 5,000 nm; and / or Approximately 1 to 100,000 nm, optionally, approximately 1 to 50,000 nm, optionally, approximately 1 to 10,000 nm, optionally, approximately 1 to 5,000 nm.

[0156] 13. The electrode as described in any one of clauses 9 to 12, wherein the thickness of the second layer (if any) is: At least about 1µm, optionally, at least about 5µm, optionally, at least about 10µm, optionally, at least about 20µm, optionally, at least about 50µm; and / or Up to about 10,000 µm, optionally, up to about 7,500 µm, optionally, up to about 5,000 µm, optionally, up to about 2,500 µm, optionally, up to about 1,000 µm; and / or Approximately 1 to 10,000 µm, optionally, approximately 5 to 7,500 µm, optionally, approximately 10 to 5,000 µm, optionally, approximately 20 to 2,500 µm, optionally, approximately 50 to 1,000 µm.

[0157] 14. The electrode as described in any of the foregoing clauses, wherein the redox active material is a cathode material, optionally selected from: (a) Metal oxides, optionally, layered metal oxides (e.g., lithium cobalt oxides, lithium nickel manganese cobalt oxides, lithium manganese nickel oxides (e.g., lithium-rich Li) 1.2 Mn 0.6 Ni 0.2 O2) and lithium nickel cobalt aluminum oxide), spinel (e.g. lithium manganese oxide) and disordered rock salt (e.g. Li) 1.25 Nb 0.25 Mn 0.5 O2); preferably lithium nickel manganese cobalt oxide (e.g., LiNi). x Mn y Co z O2, x+y+z = 1); and (b) Polyanionic compounds (e.g., lithium iron phosphate).

[0158] 15. The electrode as described in Clause 14, wherein the cathode material has an average primary particle size of about 1 to 500 nm and / or an average secondary particle size of about 1 to 300 µm.

[0159] 16. The electrode as described in any one of clauses 1 to 13, wherein the redox active material is an anode material, optionally selected from graphite, silicon, silicon oxide, Li₄Ti₅O₂. 12 Hard carbon and soft carbon.

[0160] 17. The electrode as described in Clause 16, wherein the average particle size of the anode material is from about 0.01 to 300 µm.

[0161] 18. The electrode as described in any of the foregoing clauses, wherein the capacity of the electrode is at least about 10 mA. h g -1 Optionally, at least about 200 mA h g -1 Optionally, at least about 400 mA h g -1 Optionally, at least about 600 mA h g -1 Optionally, at least approximately 800 mA h g -1 Optionally, at least about 1000 mA h g -1 .

[0162] 19. The electrode as described in any of the foregoing clauses, wherein the resistance of the electrode is at most about 1000 Ω. cm 2 Optionally, up to approximately 200 Ω cm 2 Optionally, up to approximately 150 Ω cm 2 Optionally, up to approximately 100 Ω cm 2 Optionally, up to approximately 50 Ω cm 2 Optionally, up to approximately 1 Ω cm 2 .

[0163] 20. The electrode as described in any of the foregoing clauses, wherein, based on the total weight of the electrode, the electrode contains up to about 5% by weight of adhesive, optionally up to about 4% by weight of adhesive, optionally up to about 3% by weight of adhesive, optionally up to about 2% by weight of adhesive, optionally up to about 1% by weight of adhesive, optionally up to about 0.5% by weight of adhesive, optionally up to about 0.1% by weight of adhesive, optionally up to about 0.01% by weight of adhesive.

[0164] 21. The electrode as described in any of the foregoing clauses, wherein, based on the total weight of the electrode, the electrode contains up to about 8% by weight of a redox inert and / or electronically insulating binder, optionally up to about 7% by weight, optionally up to about 6% by weight, optionally up to about 5% by weight, optionally up to about 4% by weight, optionally up to about 3% by weight, optionally up to about 2% by weight, optionally up to about 1% by weight, optionally up to about 0.5% by weight, optionally up to about 0.1% by weight, optionally up to about 0.01% by weight.

[0165] 22. The electrode as described in any of the foregoing clauses, wherein the electrode does not contain an oxidation-reduction inert binder and / or does not contain an electronic insulating binder.

[0166] 23. The electrode as described in any of the foregoing clauses, wherein the electrode does not contain an adhesive (e.g., a polymeric adhesive such as polyvinylidene fluoride or polytetrafluoroethylene).

[0167] 24. The electrode as described in any one of clauses 1 to 22, wherein the electrode comprises one or more adhesives having redox activity and / or electronic conductivity, optionally wherein the one or more adhesives having redox activity and / or electronic conductivity are independently selected from polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), carboxymethyl cellulose (CMC), styrene-butadiene rubber (SBR), polyacrylic acid (PAA), vinyl adhesives, cellulose-based adhesives, polyaniline-based adhesives, polypyrrole-based adhesives, polylactic acid-based adhesives, and chitosan-based adhesives.

[0168] 25. The electrode as described in any one of clauses 1 to 21 and 24, wherein the electrode comprises one or more adhesives that enhance adhesion and / or flexibility, optionally wherein the one or more adhesives that enhance adhesion and / or flexibility are independently selected from polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), carboxymethyl cellulose (CMC), styrene-butadiene rubber (SBR), polyacrylic acid (PAA), vinyl adhesives, polylactic acid adhesives, ethylene glycol adhesives, and methacrylic acid adhesives.

[0169] 26. An electrode as described in any of the preceding clauses, wherein the electrode is located near a current collector, optionally wherein the current collector comprises a metal, optionally aluminum, copper, or stainless steel, optionally wherein: (a) The redox-active material is the cathode material, and the current collector contains aluminum; or (b) The redox active material is the anode material, and the current collector contains copper.

[0170] 27. The electrode as described in Clause 26, wherein the current collector is surface-treated, optionally using carbon (optionally a low-dimensional carbon material) and / or metal (optionally silver and / or manganese).

[0171] 28. The electrode as described in Clause 26 or 27, wherein the thickness of the current collector is approximately 3 nm to 1 mm.

[0172] 29. A battery comprising one or more electrodes as described in Clauses 1 to 28.

[0173] 30. The battery as described in Clause 29, wherein the battery has a pouch battery structure, a cylindrical battery structure, a prismatic battery structure, or a button battery structure.

[0174] 31. A method for forming an electrode, wherein the method comprises: Preparation of aggregates comprising a redox-active material and at least one layer comprising a low-dimensional carbon material; and The aggregates are pressed to form electrodes, wherein: At least approximately 70% of the electrode surface contains at least one layer comprising low-dimensional carbon material; and Based on the total weight of the low-dimensional carbon material and the redox active material in the electrode, the electrode contains up to about 45% by weight of low-dimensional carbon material.

[0175] 32. The method of Clause 31, wherein at least about 75% of the electrode surface comprises at least one layer comprising a low-dimensional carbon material, optionally at least about 80%, optionally at least about 85%, optionally at least about 90%, optionally at least about 95%, optionally at least about 99%.

[0176] 33. The method as described in Clause 31 or 32, wherein the electrode comprises up to about 40% by weight of low-dimensional carbon material, optionally up to about 35% by weight of low-dimensional carbon material, optionally up to about 30% by weight of low-dimensional carbon material, optionally up to about 25% by weight of low-dimensional carbon material, optionally up to about 20% by weight of low-dimensional carbon material, optionally up to about 15% by weight of low-dimensional carbon material, optionally up to about 10% by weight of low-dimensional carbon material.

[0177] 34. The method of any one of clauses 31 to 33, wherein the preparation of the aggregate comprises: Prepare a first layer, wherein the first layer comprises a low-dimensional carbon material. A second layer is placed on top of the first layer, wherein the second layer comprises a redox-active material, and A third layer is placed on top of the second layer, wherein the third layer comprises a low-dimensional carbon material; and The suppression of the aggregates includes suppressing the first, second, and third layers.

[0178] 35. The method of any one of clauses 31 to 34, wherein the pressing is carried out at the following temperature: Up to approximately 250°C, optionally; up to approximately 200°C, optionally; up to approximately 150°C, optionally; up to approximately 100°C, optionally; up to approximately 50°C, optionally; up to approximately 40°C, optionally; up to approximately 30°C; and / or Approximately -50 to 250°C, optional; approximately -30 to 200°C, optional; approximately -20 to 150°C, optional; approximately -10 to 100°C, optional; approximately 0 to 50°C, optional; approximately 10 to 40°C, optional; approximately 20 to 30°C.

[0179] 36. The method of any one of clauses 31 to 35, wherein the pressing comprises calendering; optionally, at a pressure of about 0.01 to 2 m s -1 The calendering speed is used for calendering, where "calendering speed" refers to the speed at which the material passes through the calendering equipment.

[0180] 37. The method as described in Clause 36, wherein the calendering comprises asymmetric calendering, optionally wherein the operating speed of the first roll is approximately 0.1 to 0.5 m. s -1 The second roller operates at a speed of approximately 0.8 to 1.3 m. s -1 .

[0181] 38. The method of any one of clauses 31 to 37, wherein the at least one layer comprising a low-dimensional carbon material is substantially porous and / or permeable to gases (e.g., air or argon).

[0182] 39. The method of any one of clauses 31 to 38, further comprising removing a gas (e.g., air or argon) from the redox-active material through one or more layers of at least one layer comprising a low-dimensional carbon material.

[0183] 40. The method of any one of clauses 31 to 39, wherein the pressing comprises using pressure: At least about 0.5 MPa, optionally at least about 1 MPa, optionally at least about 3 MPa, optionally at least about 5 MPa, optionally at least about 7 MPa, optionally at least about 9 MPa, optionally at least about 10 MPa; and / or Up to approximately 1000 MPa, optionally up to approximately 800 MPa, optionally up to approximately 600 MPa, optionally up to approximately 400 MPa, optionally up to approximately 300 MPa, optionally up to approximately 200 MPa, optionally up to approximately 100 MPa; and / or Approximately 0.5 to 1000 MPa, optionally approximately 1 to 800 MPa, optionally approximately 3 to 600 MPa, optionally approximately 5 to 400 MPa, optionally approximately 7 to 300 MPa, optionally approximately 9 to 200 MPa, optionally approximately 10 to 100 MPa.

[0184] 41. The method of any one of clauses 31 to 40, wherein, after the pressing, the thickness of the at least one layer comprising low-dimensional carbon material (e.g., the first and third layers as described in clause 34) is: At least approximately 50nm; and / or Up to approximately 30,000 nm, optionally, up to approximately 20,000 nm, optionally, up to approximately 10,000 nm, optionally, up to approximately 5,000 nm; and / or Approximately 50 to 30,000 nm, optionally, approximately 50 to 20,000 nm, optionally, approximately 50 to 10,000 nm, optionally, approximately 50 to 5,000 nm.

[0185] 42. The method as described in any one of clauses 31 to 41, wherein, after said pressing, the thickness of the second layer (if any) is: At least about 1µm, optionally, at least about 2µm, optionally, at least about 3µm, optionally, at least about 4µm, optionally, at least about 5µm; and / or Up to about 10,000 µm, optionally, up to about 7,500 µm, optionally, up to about 5,000 µm, optionally, up to about 2,500 µm, optionally, up to about 1,000 µm; and / or Approximately 1 to 10,000 µm, optionally, approximately 2 to 7,500 µm, optionally, approximately 3 to 5,000 µm, optionally, approximately 4 to 2,500 µm, optionally, approximately 5 to 1,000 µm.

[0186] 43. The method of any one of clauses 31 to 42, wherein the method does not involve the use of a solvent (e.g., N-methyl-2-pyrrolidone or water).

[0187] 44. The method of any one of clauses 31 to 43, wherein the method does not include the use of redox inert adhesives and / or does not include the use of electronic insulating adhesives.

[0188] 45. The method of any one of clauses 31 to 44, wherein the method does not involve the use of adhesives (e.g., polymeric adhesives such as polyvinylidene fluoride or polytetrafluoroethylene).

[0189] 46. ​​The method of any one of clauses 31 to 44, wherein the method comprises using one or more adhesives having redox activity and / or electronic conductivity, optionally wherein the one or more adhesives having redox activity and / or electronic conductivity are independently selected from polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), carboxymethyl cellulose (CMC), styrene-butadiene rubber (SBR), polyacrylic acid (PAA), vinyl adhesives, cellulose-based adhesives, polyaniline-based adhesives, polypyrrole-based adhesives, polylactic acid-based adhesives, and chitosan-based adhesives.

[0190] 47. The method of any one of clauses 31 to 43 and 46, wherein the method comprises using one or more adhesives that enhance adhesion and / or enhance flexibility, optionally wherein the one or more adhesives that enhance adhesion and / or enhance flexibility are independently selected from polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), carboxymethyl cellulose (CMC), styrene-butadiene rubber (SBR), polyacrylic acid (PAA), vinyl adhesives, polylactic acid-based adhesives, ethylene glycol-based adhesives, and methacrylic acid-based adhesives.

[0191] 48. The method of any one of clauses 31 to 47, wherein the method further comprises placing one or more layers of at least one layer comprising a low-dimensional carbon material (e.g., a first layer as described in clause 34) on a current collector, optionally wherein the current collector comprises a metal (e.g., aluminum, copper, or stainless steel).

[0192] 49. The method of Clause 48, wherein the current collector comprises a first surface and a second surface, wherein the method comprises placing one or more layers of at least one layer comprising a low-dimensional carbon material (e.g., a first layer as described in Clause 34) on each of the first surface and the second surface.

[0193] 50. The method as described in Clause 48 or 49, further comprising surface treating the current collector (optionally prior to placing one or more layers of at least one layer containing low-dimensional carbon material), optionally with carbon (optionally with low-dimensional carbon material) and / or metal (optionally with silver and / or manganese).

[0194] 51. The electrode as described in any one of Clauses 1 to 28, wherein the electrode is formed using or has been formed using the method described in any one of Clauses 31 to 50.

[0195] 52. An apparatus suitable for carrying out the methods described herein.

[0196] 53. The device as described in Clause 52, comprising: (a) One or more powder feeders, optionally including a vibration mechanism (e.g., an electromagnetic vibration mechanism); and / or (b) conveyor belt; and / or (c) A compression device, optionally including one or more calendering rolls.

[0197] 54. The device as described in clauses 52 or 53, comprising an imaging device for online observation, optionally including a camera.

[0198] 55. The apparatus as described in Clause 54, further comprising components for processing and analyzing images generated by the imaging apparatus.

[0199] 56. The device as described in clause 54 or 55, wherein the device is configured to predict optimal electrode porosity, electrode microstructure, battery performance and / or manufacturing parameters based on images generated by the imaging device.

[0200] 57. The device as described in any one of Clauses 52 to 56, comprising online electronic open-loop or closed-loop control for processing electrodes.

[0201] 58. The device as described in any one of clauses 52 to 57, wherein the device is configured to simulate mechanical compression.

[0202] Any list or discussion of documents that are clearly prior to publication in this specification is not necessarily an admission that such documents are part of the state of the prior art or common general knowledge. All references disclosed herein are to be incorporated herein by reference.

[0203] All uses, methods, or product characteristics discussed herein are consistent with all other uses, methods, or products with appropriate modifications.

[0204] Those skilled in the art can identify or determine, with the aid of routine experiments, that many equivalents exist of the specific embodiments described herein. The scope of this disclosure is not intended to be limited to the foregoing description, but rather as set forth in the appended claims. Those skilled in the art will understand that various changes and modifications may be made to this description without departing from the spirit or scope of this disclosure.

Claims

1. An electrode comprising a redox active material and a low-dimensional carbon material, wherein: At least approximately 70% of the electrode surface contains at least one layer comprising low-dimensional carbon material; and Based on the total weight of the low-dimensional carbon material and the redox active material in the electrode, the electrode contains up to about 45% by weight of low-dimensional carbon material.

2. The electrode as claimed in claim 1, wherein, Based on the total weight of the low-dimensional carbon material and the redox-active material in the electrode, the electrode comprises: At least about 0.1% by weight of low-dimensional carbon material, optionally, at least about 0.5% by weight, optionally, at least about 1% by weight, optionally, at least about 1.5% by weight, optionally, at least about 2% by weight, optionally, at least about 3% by weight; and / or Up to about 40% by weight of low-dimensional carbon materials, optionally, up to about 30% by weight, optionally, up to about 20% by weight, optionally, up to about 10% by weight, optionally, up to about 8% by weight, optionally, up to about 6% by weight, optionally, up to about 5% by weight; and / or About 0.1 to 40% by weight of low-dimensional carbon materials, optionally, about 0.1 to 30% by weight, optionally, about 0.5 to 20% by weight, optionally, about 1 to 10% by weight, optionally, about 1.5 to 8% by weight, optionally, about 2 to 6% by weight, optionally, about 3 to 5% by weight, optionally, about 4% by weight.

3. The electrode as claimed in any of the preceding claims, wherein, The low-dimensional carbon material is substantially porous and / or permeable to gases (e.g., air or argon).

4. The electrode as claimed in any of the preceding claims, wherein, The low-dimensional carbon material is a zero-dimensional, one-dimensional, or two-dimensional carbon material, optionally in the form of flakes, flat surfaces, tubular or needle-shaped carbon materials.

5. The electrode as claimed in any of the preceding claims, wherein, Low-dimensional carbon materials are selected from graphene oxide, graphene, porous graphene, graphene oxide, carbon nanofibers, carbon fibers, carbon nanotubes, graphyne and grapheneene.

6. The electrode as claimed in any of the preceding claims, comprising at least two layers comprising low-dimensional carbon material.

7. The electrode as claimed in claim 6, comprising a first layer, a second layer, and a third layer; wherein: The first layer contains low-dimensional carbon materials; The second layer contains redox-active materials; The third layer contains low-dimensional carbon materials; and The second layer is located between the first and third layers.

8. The electrode as claimed in any of the preceding claims, wherein, The thickness of the at least one layer containing low-dimensional carbon material is: At least about 1 nm, optionally, at least about 10 nm, optionally, at least about 20 nm, optionally, at least about 50 nm; and / or Up to approximately 100,000 nm, optionally, up to approximately 50,000 nm, optionally, up to approximately 10,000 nm, optionally, up to approximately 5,000 nm; and / or Approximately 1 to 100,000 nm, optionally, approximately 1 to 50,000 nm, optionally, approximately 1 to 10,000 nm, optionally, approximately 1 to 5,000 nm.

9. The electrode as claimed in claim 7 or 8, wherein, When a second layer exists, the thickness of the second layer is: At least about 1µm, optionally, at least about 5µm, optionally, at least about 10µm, optionally, at least about 20µm, optionally, at least about 50µm; and / or Up to about 10,000 µm, optionally, up to about 7,500 µm, optionally, up to about 5,000 µm, optionally, up to about 2,500 µm, optionally, up to about 1,000 µm; and / or Approximately 1 to 10,000 µm, optionally, approximately 5 to 7,500 µm, optionally, approximately 10 to 5,000 µm, optionally, approximately 20 to 2,500 µm, optionally, approximately 50 to 1,000 µm.

10. The electrode as claimed in any of the preceding claims, wherein, The redox active material is a cathode material, optionally selected from: (a) Metal oxides, optionally, layered metal oxides (e.g., lithium cobalt oxides, lithium nickel manganese cobalt oxides, lithium manganese nickel oxides (e.g., lithium-rich Li) 1.2 Mn 0.6 Ni 0.2 O2) and lithium nickel cobalt aluminum oxide), spinel (e.g. lithium manganese oxide) and disordered rock salt (e.g. Li) 1.25 Nb 0.25 Mn 0.5 O2); preferably lithium nickel manganese cobalt oxide (e.g., LiNi). x Mn y Co z O2, x+y+z = 1); and (b) Polyanionic compounds (e.g., lithium iron phosphate).

11. The electrode according to any one of claims 1 to 9, wherein, The redox active material is an anode material, optionally selected from graphite, silicon, silicon oxide, or Li4Ti5O. 12 Hard carbon and soft carbon.

12. The electrode as claimed in any of the preceding claims, wherein, The electrode capacity is at least about 10 mA. h g -1 Optionally, at least about 200 mA h g -1 Optionally, at least about 400 mA h g -1 Optionally, at least about 600 mA h g -1 Optionally, at least approximately 800 mA h g -1 Optionally, at least about 1000 mA h g -1 .

13. The electrode as claimed in any of the preceding claims, wherein, The resistance of the electrodes is at most approximately 1000 Ω. cm 2 Optionally, up to approximately 200 Ω cm 2 Optionally, up to approximately 150 Ω cm 2 Optionally, up to approximately 100 Ω cm 2 Optionally, up to approximately 50 Ω cm 2 Optionally, up to approximately 1 Ω cm 2 .

14. The electrode as claimed in any of the preceding claims, wherein, The electrodes do not contain redox inert binders and / or do not contain electronic insulating binders.

15. The electrode as claimed in any of the preceding claims, wherein, The electrodes do not contain adhesives (e.g., polymeric adhesives such as polyvinylidene fluoride or polytetrafluoroethylene).

16. The electrode according to any one of claims 1 to 14, wherein, The electrode comprises one or more adhesives having redox activity and / or electronic conductivity, optionally wherein the one or more adhesives having redox activity and / or electronic conductivity are independently selected from polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), carboxymethyl cellulose (CMC), styrene-butadiene rubber (SBR), polyacrylic acid (PAA), vinyl adhesives, cellulose-based adhesives, polyaniline-based adhesives, polypyrrole-based adhesives, polylactic acid-based adhesives, and chitosan-based adhesives.

17. The electrode according to any one of claims 1 to 13 and 16, wherein, The electrode comprises one or more adhesives that enhance adhesion and / or flexibility, optionally wherein the one or more adhesives that enhance adhesion and / or flexibility are independently selected from polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), carboxymethyl cellulose (CMC), styrene-butadiene rubber (SBR), polyacrylic acid (PAA), vinyl adhesives, polylactic acid adhesives, ethylene glycol adhesives, and methacrylic acid adhesives.

18. A battery comprising one or more electrodes as claimed in any one of claims 1 to 17.

19. The battery of claim 18, wherein, The battery has a pouch battery structure, a cylindrical battery structure, a prismatic battery structure, or a button battery structure.

20. A method for forming an electrode, wherein, The method includes: Preparation of aggregates comprising a redox-active material and at least one layer comprising a low-dimensional carbon material; and The aggregates are pressed to form electrodes, wherein: At least approximately 70% of the electrode surface contains at least one layer comprising low-dimensional carbon material; and Based on the total weight of the low-dimensional carbon material and the redox active material in the electrode, the electrode contains up to about 45% by weight of low-dimensional carbon material.

21. The method of claim 20, wherein, The preparation of the aggregates includes: Prepare a first layer, wherein the first layer comprises a low-dimensional carbon material. A second layer is placed on top of the first layer, wherein the second layer comprises a redox-active material, and A third layer is placed on top of the second layer, wherein the third layer comprises a low-dimensional carbon material; and The aggregate suppression includes suppressing the first, second, and third layers.

22. The method of claim 20 or 21, wherein, The pressing is performed at the following temperatures: Up to approximately 250°C, optionally; up to approximately 200°C, optionally; up to approximately 150°C, optionally; up to approximately 100°C, optionally; up to approximately 50°C, optionally; up to approximately 40°C, optionally; up to approximately 30°C; and / or Approximately -50 to 250°C, optional; approximately -30 to 200°C, optional; approximately -20 to 150°C, optional; approximately -10 to 100°C, optional; approximately 0 to 50°C, optional; approximately 10 to 40°C, optional; approximately 20 to 30°C.

23. The method according to any one of claims 20 to 22, wherein, The pressing includes calendering; optionally, at a pressure of about 0.01 to 2 m. s -1 The calendering speed is used for calendering, where "calendering speed" refers to the speed at which the material passes through the calendering equipment.

24. The method of claim 23, wherein, The calendering includes asymmetric calendering, and optionally, the first roll operates at a speed of approximately 0.1 to 0.5 m. s -1 The second roller operates at a speed of approximately 0.8 to 1.3 m. s -1 .

25. The method according to any one of claims 20 to 24, wherein, The at least one layer comprising low-dimensional carbon material is substantially porous and / or permeable to gases (e.g., air or argon).

26. The method of any one of claims 20 to 25, further comprising removing a gas (e.g., air or argon) from the redox-active material through one or more layers of at least one layer comprising a low-dimensional carbon material.

27. The method according to any one of claims 20 to 26, wherein, The compression includes using the following pressures: At least about 0.5 MPa, optionally at least about 1 MPa, optionally at least about 3 MPa, optionally at least about 5 MPa, optionally at least about 7 MPa, optionally at least about 9 MPa, optionally at least about 10 MPa; and / or Up to approximately 1000 MPa, optionally up to approximately 800 MPa, optionally up to approximately 600 MPa, optionally up to approximately 400 MPa, optionally up to approximately 300 MPa, optionally up to approximately 200 MPa, optionally up to approximately 100 MPa; and / or Approximately 0.5 to 1000 MPa, optionally approximately 1 to 800 MPa, optionally approximately 3 to 600 MPa, optionally approximately 5 to 400 MPa, optionally approximately 7 to 300 MPa, optionally approximately 9 to 200 MPa, optionally approximately 10 to 100 MPa.

28. The method according to any one of claims 20 to 27, wherein, The method does not involve the use of solvents (e.g., N-methyl-2-pyrrolidone or water).

29. The method according to any one of claims 20 to 28, wherein, The method does not include the use of redox inert adhesives and / or does not include the use of electronic insulating adhesives.

30. The method according to any one of claims 20 to 29, wherein, The method does not involve the use of adhesives (e.g., polymeric adhesives such as polyvinylidene fluoride or polytetrafluoroethylene).

31. The method according to any one of claims 20 to 29, wherein, The method includes using one or more adhesives having redox activity and / or electronic conductivity, optionally wherein the one or more adhesives having redox activity and / or electronic conductivity are independently selected from polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), carboxymethyl cellulose (CMC), styrene-butadiene rubber (SBR), polyacrylic acid (PAA), vinyl adhesives, cellulose-based adhesives, polyaniline-based adhesives, polypyrrole-based adhesives, polylactic acid-based adhesives, and chitosan-based adhesives.

32. The method according to any one of claims 20 to 28 and 31, wherein, The method includes using one or more adhesives that enhance adhesion and / or flexibility, optionally wherein the one or more adhesives that enhance adhesion and / or flexibility are independently selected from polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), carboxymethyl cellulose (CMC), styrene-butadiene rubber (SBR), polyacrylic acid (PAA), vinyl adhesives, polylactic acid-based adhesives, ethylene glycol-based adhesives, and methacrylic acid-based adhesives.

33. The electrode according to any one of claims 1 to 17, wherein, The electrode is formed using the method described in any one of claims 20 to 32 or has been formed using the method described in any one of claims 20 to 32.

34. An apparatus suitable for carrying out the methods described herein.

35. The device of claim 34, comprising: (a) One or more powder feeders, optionally including a vibration mechanism (e.g., an electromagnetic vibration mechanism); and / or (b) conveyor belt; and / or (c) A compression device, which optionally includes one or more calendering rolls.

36. The device of claim 34 or 35, further comprising an imaging device for online observation, optionally including a camera.

37. The apparatus of claim 36, further comprising components for processing and analyzing images generated by the imaging device.

38. The device as claimed in claim 36 or 37, wherein, The device is configured to predict optimal electrode porosity, electrode microstructure, battery performance, and / or manufacturing parameters based on images generated by the imaging device.

39. The device according to any one of claims 34 to 38, comprising online electronic open-loop or closed-loop control for processing electrodes.

40. The device as claimed in any one of claims 34 to 39, wherein, The device is configured to simulate mechanical compression.

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