Method for manufacturing electrodes for energy storage devices and dried electrode films for energy storage devices.

Abstract

The present invention provides a method for manufacturing electrodes for energy storage devices and a composition that facilitates the formation of thinner electrode films by reducing the binder material content while maintaining desirable mechanical and / or electrical performance. [Solution] The energy storage device 100 comprises a cathode 102 (104), an anode 104 (102), and a separator 106 between the cathode and the anode, wherein the anode and / or cathode comprises electrode films 112, 114, 116, 118 containing a superfibrillated binder material and carbon. The method for manufacturing the electrode films includes a fibrillation process using a slow rate and / or high processing pressure so that the fibrillation of the binder material can be enhanced. The electrode films contain conductivity-enhancing additives to promote a reduction in equivalent series resistance.

Description

Technical Field

[0001] The present invention relates to an energy storage device, and particularly to a composition and a manufacturing method of an electrode for an energy storage device.

Background Art

[0002] Various types of energy storage devices can be used to supply power to electrical equipment. Examples of such electrical equipment include, for example, capacitors, batteries, capacitor - battery hybrids, and / or fuel cells. Any energy storage device, such as a lithium - ion capacitor, can improve the electrical performance of the capacitor by improving the composition of its electrodes.

Summary of the Invention

[0003] To summarize the present invention and the advantages over the prior art achieved by the present invention, certain objectives and advantages are described herein. Not all such objectives or advantages are necessarily achieved by a particular embodiment. Thus, for example, one skilled in the art will understand that the present invention can be embodied or implemented without necessarily achieving one advantage or group of advantages described or suggested herein, in a manner that achieves or optimizes one advantage or group of advantages described herein.

[0004] In a first aspect, there is provided an electrode for use in an energy storage device, comprising dried carbon particles, dried ultra - fibrillated binder particles, and a current collector, and having a self - supporting dry electrode film.

[0005] ​​​​In one embodiment of the first aspect, the dry electrode film has a thickness of approximately 50 μm to approximately 120 μm. It has. In one embodiment of the first aspect, the electrode is an anode. In one embodiment, the self-standing dry electrode film further contains conductive carbon. In one embodiment of this model, the electrode film contains approximately 1% to 5% by mass of conductive carbon It contains. In one embodiment of the first aspect, the electrode is an electrolyte containing a lithium salt. It is in ionic contact with the cathode. In one embodiment of the first aspect, the electrolyte is further in cathode with Ionic contact is present. In one embodiment of the first aspect, dried superfibrillated bi The ion particles constitute approximately 3% to 7% by weight of the self-supporting dry electrode film. In one embodiment, a lithium-ion capacitor comprising electrodes is provided.

[0006] In the second embodiment, dried carbon particles and dried fibrillable binder particles are The process of forming a first dry electrode mixture containing and the bit in the dry electrode film mixture The denture is superfibrillated, and the superfibrillated matrix is ​​placed in the electrode film mixture. The process involves forming the electrode film and then calendering the resulting ultrafibrillated electrode film mixture. The process includes the step of forming a self-supporting superfibrillated electrode film.

[0007] In one embodiment of the second aspect, the above method substantially does not use treatment additives. This is a dry method. In one embodiment of the second aspect, the above method is a self-supporting electrode film The process further includes the step of bringing the current collector into contact with the current collector to form a first electrode. One embodiment in a second aspect In this state, the above method includes the steps of forming a second electrode and separating the first electrode and the second electrode. The process further includes the step of inserting a . In one embodiment of the second aspect, the first electrode is an ano In one embodiment of the second aspect, the self-standing drying electrode film is approximately 50 μm to approximately It has a thickness of 120 μm. In one embodiment of the second, a dried superfibrillated binder The particles contain approximately 3% to 7% by weight of a superfibrillated matrix. In the second embodiment, In one embodiment, the step of forming the first mixture is to combine conductive carbon particles with the first mixture. The process further includes adding to the mixture. In one embodiment of the second aspect, the first mixture is It contains approximately 1% to 5% by mass of conductive carbon particles. One embodiment in the second aspect. So, the process of ultrafibrillating the binder involves the binder in the dry electrode film mixture A step of fibrillation to form a first fibrillation matrix, and the first fibrillation matrix The process involves destroying trichrix to form a powder mixture of carbon particles and fibrillated binder particles. The powder mixture is fibrillated to produce a second superfibrillated matrix containing the above-mentioned superfibrillated matrix. The process includes the step of forming a fibrillated matrix.

[0008] This specification includes at least one color drawing. A copy of this color drawing may be obtained upon request. The Office provides this service upon payment of the necessary fees.

[0009] Features, embodiments, and advantages disclosed herein or otherwise are shown in the figures of specific embodiments. These drawings are described with reference to the surface. These drawings are intended to illustrate specific embodiments. Therefore, this does not limit the present invention. [Brief explanation of the drawing]

[0010] [Figure 1]It is a side cross-sectional view schematically showing an example of an energy storage device according to an embodiment. [Figure 2] It is a flowchart showing an example of the steps of a method for manufacturing an electrode film. [Figure 3] It is a table showing the performance of the equivalent series resistance of each of the lithium-ion capacitor cells having anodes containing different types of conductivity promoting additives. [Figure 4] It is a flowchart showing an example of a method for manufacturing a thin electrode film. [Figure 5A] It is a schematic diagram of a pay-out machine for the calender line of an electrode film. [Figure 5B] It is a diagram showing in detail a part of the pay-out machine shown in FIG. 5A. [Figure 6A] It shows a SEM image of an electrode film prepared by a conventional dry electrode treatment. [Figure 6B] It shows a SEM image of an electrode film prepared by a dry electrode treatment using a super fibrillated binder. [Figure 7] It is a table showing data of various embodiments of a lithium-ion capacitor having an anode manufactured by the method shown in this specification.

[0011] Specific embodiments and examples are described below. Those skilled in the art will understand that the present invention is specific to the embodiments and / or uses disclosed herein, obvious modifications and their equivalents. It will be understood. Therefore, the scope of the present invention disclosed in this specification should not be limited by the specific embodiments described below.

[0012] In some embodiments, an energy storage device such as a lithium ion capacitor (LiC) having improved electrical and / or mechanical performance is provided. In some embodiments the device can include an electrode containing an improved electrode film composition. Therefore, it can provide improved electrical and / or mechanical performance. In that embodiment, the electrodes may be an anode and / or a cathode.

[0013] The disclosed embodiments provide enhanced fibrillation of the binder material compared to conventional methods. That is, electrode film material that has undergone "superfibrillation" as defined and described herein. This may include mixtures, electrode films, electrodes, energy storage devices, and related methods. It is possible. Many advantages in electrical and / or mechanical performance include enhanced fibrillation of the binder. This can be achieved by [method].

[0014] For example, by enhancing the fibrillation of the binder, the binder's adhesion and f The film strength can be increased. Such embodiments are equivalently fibrillated. Using the same or less amount of binder as a comparable film that does not have a binder. This can enable the manufacture of thinner films. Using thinner films allows for dry Due to the self-supporting properties of the dry electrode film and other reasons, conventional wet electrode processing is not used. This could be beneficial for dry electrode film technology, where the film becomes thicker than required by law. Furthermore, the binder in the electrode film is proportional to some of the other materials, such as the conductive material. Reducing the weight percentage ("binder filling amount") offers advantages in terms of electrical performance. There are, for example, the use of a superfibrillated binder and the binder in the electrode film Reducing the amount of da also means that conventional films with conventional fibrillation binders In comparison, it reduces the undesirable electrical series resistance (ESR) in devices that use film. It is possible.

[0015] In some embodiments, the electrode films of the anode and / or cathode are made of fiber It may contain a lylizable binder material and other electrode materials such as carbon. Extreme films can reduce the amount of binder material while maintaining desirable mechanical properties. Such desirable mechanical properties are, for example, in the manufacture of energy storage devices. This may relate to the mechanical properties required for more than one process. For example, dry manufacturing methods. When manufacturing electrodes by this method, the self-supporting electrode film is attached to the current collector before the film is bonded to the current collector. This provides sufficient stability to be advantageous for winding and handling, or for other types of handling. It is possible. Furthermore, by enhancing the fibrillation of the binder material, the calendar line can be created. This can advantageously facilitate the formation of thinner electrode films that can withstand the tension. In some embodiments, an increased number of fibrils, a larger fibril surface area, Electrode films containing and / or longer fibrils are desired during film manufacturing. To reduce the thickness of the film while maintaining sufficient mechanical strength to preserve its integrity. It is possible.

[0016] The method for manufacturing electrode films is compared to the conventional fibrillation process for electrode films. Therefore, the processing speed is slowed down so that the fibrillation of the binder material can be enhanced. The process may include a fibrillation step with increased processing pressure. For example, When fibrillation is enhanced, the number of fibrils increases, the surface area of ​​the fibrils increases, and / Alternatively, longer fibrils can be obtained from the binder material, compared to the fibrils of conventional electrode films. While using a smaller amount of binder material compared to chemical treatment processes, it maintains the desired mechanical properties. This is possible. Such increases in the number of fibrils, increases in the surface area of ​​the fibrils, and / Alternatively, longer fibrils can lead to a more effective matrix in electrode films. This allows for the construction of a structural frame, which provides one or more advantages as described herein. It is thought that in some embodiments, this more effective matrix structure is compared to Compared to conventional dry electrode technology, it offers increased tensile strength, shear stress, and compression in the longitudinal direction. Resistance to stress and / or torsional stress, reduction in film thickness, and increase in film density. This results in a reduction in the amount of binder. In certain embodiments, the electrode film is as shown herein. This is a self-supporting electrode film with a reduced amount of binder.

[0017] In certain embodiments, the electrode film comprises superfibrillated binder particles and carbon particles. It contains a self-supporting electrode film. The ultrafibrillated binder particles undergo approximately 200 processing steps. Binder particles manufactured according to the manufacturing methods described herein, such as bi / or 400 These are binder particles that are fibrillated, reduced in size, and then refibrillated. And, at higher pressure, slower speed, and slower supply rate than conventional fibrillation technology. , and / or binder particles that are fibrillated over a longer period of time. Brillated binder particles are characterized by the number of fibrils, the surface area of ​​the fibrils, and / or fibrils. It can be structurally defined based on the length of the rill, and all of them are conventional binders Compared to the brillation technology, this increases. The superfibrillation matrix shown herein is an electrode It is a structure formed by the components of the film mixture, and by fibrillation treatment, The da particles are superfibrillated to the point where they stick together, as shown in Figure 6B, for example. It has a structure that is neither compressed nor formed into an electrode film.

[0018] In some embodiments, these superfibrillated binder particles have a maximum size of approximately 3 μm Less than (micron), less than approximately 2 μm, less than approximately 1 μm, less than approximately 0.5 μm, less than approximately 0.3 μm, less than approximately 0.1 μm For example, values ​​less than approximately 0.05 μm, less than approximately 0.03 μm, less than approximately 0.01 μm, or values ​​in between. This means the particle size is approximately 0.01-3 μm, approximately 0.03-2 μm, approximately 0.05-1 μm, or approximately 0.1 μm-0.3 μm. Characterized by: In yet another embodiment, the superfibrillated matrix is ​​carbon It contains particles, and the carbon particles make up at least 10%, at least 20%, at least 30%, and less At least 40%, at least 50%, at least 60%, at least 70%, at least 80%, and less At least 90%, at least 95%, or at least 99% of the surface area, or a range in between these. The binder particles come into contact with the surface area of ​​the range. In some embodiments, the superfibrillated Inda particles, compared to conventional dry-processed electrode films with equivalent binder mass, Therefore, the number present in the electrode film is at least twice as large.

[0019] Dry particle electrodes manufactured using standard techniques with conventional fibrillation binders. Conventional dry electrode films, produced from film mixtures by dry processing, are generally The anode is characterized by having a thickness of approximately 120 μm or more, and the cathode The do is characterized by its thickness of approximately 80 μm or more. These two types The reason for the difference in the thickness of the dry electrodes is that the anode electrode film is thicker than the cathode electrode film. This is because it is difficult to compress, and for example, at least partially, Compared to the activated carbon in the sword electrode film, it is difficult to compress the carbon material of the anode. Therefore, conventional cathode films are typically about 80 μm to about 10,000 μm thick. The size can be in the range of μm, and the anode film can be in the range of approximately 120 μm to approximately 10,000 μm.

[0020] In some embodiments, the fibrillation of the binder material is increased compared to conventional dry electrode treatment. By strengthening the material, it becomes easier to form thinner electrode films. Furthermore, if the electrode film is thin, it can occupy a smaller volume and be used in lithium-ion capacitors. It is possible. In some embodiments, the ultrafibrillation of the binder material is a conventional method. Structural completion of other similar conventional dry electrode films having a librized dry binder material While maintaining overall properties and / or electrical performance, the thickness can be approximately 80 μm, 60 μm, or 50 μm or less. This facilitates the formation of a cathode electrode film with thickness. Several implementations In this configuration, the electrode film produced by one or more processing steps described herein is approximately 120 μm The electrodes can have thicknesses of m, 80 μm, 60 μm, and even less than approximately 50 μm, and the electrodes can be arbitrarily It is an anode. In some embodiments, when the fibrillation of the binder material is enhanced, The formation of anode electrode films with a thickness of less than 120 μm can be facilitated. In the application method, by enhancing the fibrillation of the binder material, for example, a thickness of 120 μm Thin electrode fills such as less than 80 μm, less than 60 μm, less than 50 μm, less than 40 μm, less than 30 μm Manufacturing of anode electrode films, for example, anode electrode films with a thickness of less than 120 μm or thinner, and thickness Thinner electrodes such as cathode electrode films that are less than 120 μm, less than 80 μm, or thinner. The manufacturing of electrode films can be facilitated. In some embodiments, thinner electrode films The film can provide lithium-ion capacitors with improved power performance. In some embodiments, the anode used in lithium-ion capacitors is approximately 40 μm~ Approximately 120μm, approximately 50μm to approximately 120μm, approximately 50μm to approximately 80μm, approximately 60μm to approximately 100μm, approximately 80μm to approximately 120 The electrode film has a thickness of μm. In some embodiments, lithium ion The cathodes used in the japashita are approximately 40 μm to 80 μm, approximately 40 μm to 70 μm, and approximately 50 μm to 8 The device includes electrode films with thicknesses ranging from 0 μm to approximately 50 μm to 70 μm.

[0021] In some embodiments, the electrode film is conductive to facilitate a reduction in equivalent series resistance. It contains performance-enhancing additives. These additives are carbon black and / or graphite. It may also be the case that, in some embodiments, this electrode film is a conventional electrode film and In comparison, the amount of binder material is small, and the amount of one or more conductivity-enhancing additives is large, and therefore Therefore, the electrode film according to this embodiment maintains desirable mechanical properties while being equivalent to a series It shows a decrease in resistance.

[0022] Lithium iodine comprising one or more electrodes containing the electrode film composition described herein The capacitor exhibits a favorable reduction in equivalent series resistance, which is compared to conventional electrode films. It provides a capacitor with a higher power density compared to others. In some embodiments, improved versions are available. The series resistance suppresses heat generation, thereby reducing the heat generated by the lithium-ion battery, which has an electrode film similar to that of conventional lithium-ion batteries. To reduce or avoid heat dissipation from the capsule. In some embodiments, the electric power described herein A lithium-ion capacitor comprising one or more electrodes containing an electrode film composition is more It can be manufactured at low cost. In some embodiments, one or more electric devices as described herein Lithium-ion capacitors containing electrode compositions are prism-type, cylindrical and / or bo It can have various shapes, including a tan shape. In some embodiments, as described herein Lithium-ion capacitors equipped with electrolytes are used in hybrid electric vehicles (HEVs), and Powering hybrid electric vehicles (PHEVs) and / or electric vehicles (EVs) It can be used for supplying.

[0023] The electrodes and energy storage devices described herein are in the context of lithium-ion capacitors. This can be explained, but the embodiment is one or more batteries, with or without lithium. Battery, capacitor, capacitor-battery hybrid, fuel cell, combination of these any of the many energy storage devices and systems, including and equivalent thereto. It can be used in some embodiments. In some embodiments, the electrodes are an ultracapacitor, lithium io A cathode configured for use in a capacitor or lithium-ion battery. This is the anode. In a preferred embodiment, the electrode is used in a lithium-ion capacitor. It is an anode configured in such a way.

[0024] Figure 1 is a schematic lateral cross-sectional view of an example of an energy storage device 100. 00 may be a lithium-ion capacitor. Of course, other energy storage devices may also be used. Within the scope of the present invention, batteries, capacitor-battery hybrids, and / or It should be understood that this may include a fuel cell. The energy storage device 100 includes a first electrode 10 2. It comprises a second electrode 104 and a separator 106 positioned between the first electrode 102 and the second electrode 104. For example, the first electrode 102 and the second electrode 104 are opposite each other on the separator 106. They can be arranged adjacent to each other on the surface. The first electrode 102 may also be a cathode. The second electrode 104 may be an anode, or vice versa (the first electrode 102 is an anode). The second electrode 104 may be a cathode. The energy storage device 100 is an energy storage device An electrolyte 122 can be provided to facilitate ion transfer between electrodes 102 and 104 of the device 100. Alternatively, the electrolyte 122 may be in contact with the first electrode 102, the second electrode 104, and the separator 106. The electrolyte 122, first electrode 102, second electrode 104, and separator 106 are located in the energy storage device. It may be housed within the housing 120. For example, the housing 120 of the energy storage device is An energy storage device is formed by introducing an electrode 102, a second electrode 104, a separator 106, and an electrolyte 122. After impregnating 100 with electrolyte 122, the first electrode 102, second electrode 104, separator 106 and electrolytic Quality 122 may be sealed so as to be physically sealed from the environment outside the housing. The ghee storage device 100 is shown as a double-electrode, double-layer device, but other devices such as a single-layer electrode are also available. It will be understood that it is acceptable to implement different types.

[0025] The energy storage device 100 is equipped with any of several different types of electrolytes 122. It is possible to do so. For example, the device 100 is equipped with the electrolyte of a lithium-ion capacitor. This electrolyte can be made by including a lithium source such as a lithium salt and a solvent such as an organic solvent. It is possible. In some embodiments, the lithium salt is lithium hexafluorophosphate. Lithium (LiPF6), lithium tetrafluoroborate (LiBF4), lithium perchlorate (LiClO4) , bis(trifluoromethanesulfonyl)imido lithium (LiN(SO2CF3)2), triflu Lithium olomethanesulfonate (LiSO3CF3), combinations thereof, and / or it This includes equivalents to those mentioned above. In some embodiments, the solution of the lithium-ion capacitor electrolyte The medium may contain one or more types of ethers and / or esters. For example, lith The solvent for the electrolyte of a um ion capacitor is ethylene carbonate (EC) and dimethyl carbonate. Diethyl carbonate (DMC), diethyl carbonate (DEC), ethyl methyl carbonate (EMC), vinyl Polycarbonate (VC), propylene carbonate (PC), combinations thereof, and / Or it may contain equivalents. For example, the electrolyte may be LiPF6, ethylene carbonate It may contain carbonates, propylene carbonates, and diethyl carbonates.

[0026] The separator 106 has two adjacent electrodes on opposite sides of the separator 106, for example, the first electrode Electrode 102 and the second electrode 104 are electrically insulated, while ion transfer between the two adjacent electrodes is maintained. It can be configured to enable this. Separator 106 is a porous electrical insulation The material may include... In some embodiments, the separator 106 includes a polymer material. It is possible to do so. For example, separator 106 is made of cellulose material (e.g., paper), polyethylene Polyethylene (PE) material, polypropylene (PP) material, and / or polyethylene and polyp It may contain polypropylene material.

[0027] As shown in Figure 1, the first electrode 102 and the second electrode 104 are connected to the first current collector 108 and the second current collector 110 Each is equipped with the following: The first current collector 108 and the second current collector 110 have corresponding electrodes and external circuits (not shown). (without) the electrical coupling between the first current collector 108 and / or the second The current collector 110 may contain one or more conductive materials and / or corresponding electrical components. A pole, and terminals for connecting an external circuit such as an external electrical circuit with the energy storage device 100. They can be made into various shapes and dimensions that facilitate the movement of electric charge between them. For example, cluster The electrolytic body is made of materials such as aluminum, nickel, copper, silver, and alloys thereof. It may include material. For example, the first current collector 108 and / or the second current collector 110 may be rectangular. It may include aluminum foil in a rectangular or substantially rectangular shape, and the corresponding electrodes and Desired charge transfer between the external electrical circuit (e.g., current collector plate and / or electrodes) via another component of the energy storage device configured to electrically connect to an external electrical circuit It can be made into dimensions that allow for the movement of electric charge.

[0028] The first electrode 102 is the first electrode on the first surface of the first current collector 108 (for example, the upper surface of the first current collector 108) The film 112 (for example, the upper electrode film) and the opposing second surface of the first current collector 108 (e.g. For example, the second electrode film 114 (for example, the lower electrode film) on the bottom surface of the first current collector 108 and , is provided. Similarly, the second electrode 104 is on the first surface of the second current collector 110 (for example, the second current collector The first electrode film 116 (for example, the upper electrode film) on the upper surface of 110 and the second current collector 110 The second electrode film 118 on the opposing second surface (for example, the bottom surface of the second current collector 110), It is equipped. For example, the first surface of the second current collector 110 faces the second surface of the first current collector 108. The separator 106 is the second electrode film 114 of the first electrode 102 and the first electrode film of the second electrode 104. It is adjacent to Mu116.

[0029] Electrode films 112, 114, 116 and / or 118 are available in various suitable shapes, dimensions, and / Alternatively, it can be the thickness. For example, the electrode film can be approximately 100 μm (microns) to approximately 25 It can have a thickness ranging from approximately 30 μm to approximately 250 μm, including 0 μm.

[0030] In some embodiments, electrode films such as electrode films 112, 114, 116 and / or 118 One or more of the films may contain a mixture containing a binder material and carbon. In some embodiments, the electrode film contains one or more additives, such as conductivity-enhancing additives. It may contain a lithium-ion capacitor cathode. The electrode film contains one or more carbon-based electroactive components, such as porous carbon materials. It may contain an electrode film mixture having a cathode The porous carbon material contains activated carbon. For example, the electrode film of a cathode is a binder material. It may contain activated carbon and conductivity-enhancing additives. In some embodiments, The electrode film of the anode of a lithium-ion capacitor reversibly injects lithium ions. It contains an electrode film mixture containing carbon configured to allow tarkalation. In some embodiments, the carbon intercalating the lithium is graphite. For example, the electrode film of the anode is made of a binder material, graphite, and conductivity-enhancing additives. It may contain an agent.

[0031] In some embodiments, the binder material is one or more fibrillable binder components It may include this fibrillation. For example, the process of forming an electrode film is this fibrillation possible. The binder component is fibrillated so that the electrode film contains the fibrillated binder. It is possible. In some embodiments, this fibrillation binder is described herein. It contains superfibrillated binder particles. The binder component provides multiple fibrils. It may be fibrillated, and this fibril may be one or more other components of the film. To provide the desired mechanical support to the matrix, grid and / or fibril. Alternatively, a web can be formed to give the electrode film the desired mechanical structure. For example. For example, the cathode and / or anode of a lithium-ion capacitor may be one or more types of ions. It may comprise one or more electrode films containing a brillated binder component. In that embodiment, the binder component is polytetrafluoroethylene (PTFE), ultra-high molecular weight. Polyethylene (UHMWPE) and / or other suitable fibrillable materials, alone "T" can be included in combination.

[0032] In some embodiments, the electrode film maintains the desired mechanical properties while being conventional The binder material weighs less than known dry electrode films. In some embodiments, The electrode film is approximately 1% to 10% by weight, approximately 3% to 15% by weight, and approximately 3% to 10% by weight. Quantity %, approximately 3% to approximately 8% by weight, approximately 3% to approximately 7% by weight, approximately 3% to approximately 6% by weight, or approximately It contains 3% to approximately 5% by weight of binder material. In other embodiments, the electrode film is For example, approximately 5% to 6% by weight or approximately 6.5% to 8% by weight, or approximately 4% to 7% by weight It is an anode containing a binder material. In some embodiments, the electrode film is about A binder material in an amount of 7% to approximately 11% by weight, for example, approximately 8% to approximately 10% by weight, together with activated carbon. It contains a cathode. In some embodiments, it contains an electrode film such as an anode film. The binder material content is less than approximately 4% by weight or less than 3% by weight, for example, about 0.5% by weight. This is %~4% by weight, 1%~4% by weight, 0.5%~3% by weight, or 1%~3% by weight. In some embodiments, electrode films with a small amount of binder are subjected to tension and shearing. It is possible to maintain the desired resistance to compressive and / or torsional stresses.

[0033] In some embodiments, the electrode film has a binder compared to other materials in the film. Because the amount of material is small, the amount of conductivity-enhancing additive can be increased, thereby improving electrical performance. For example, an anode according to such an embodiment maintains the desired mechanical properties or While improving the equivalent series resistance, it is possible to demonstrate an improvement in the equivalent series resistance. In some embodiments, To obtain the desired electrical performance, a specific type of conductivity-enhancing additive is incorporated into the electrode film. This can be achieved. For example, an electrode film with a low binder content has an equivalent series resistance. While showing improvement, desired resistance to tensile, shear, compressive and / or torsional stresses It can demonstrate resistance to other conventional energy storage devices of comparable structure. In comparison, energy storage devices such as lithium-ion capacitors have a high power density. Manufacturing becomes easier.

[0034] In some embodiments, the conductivity-enhancing additive includes conductive carbon. In the application method, conductive carbon is one or more types of carbon black and / or graphite Includes light. In some embodiments, one or more of the above carbon blacks are commercial, {Shoyo} Ketjenblack (registered trademark) made by Akzo Nobel NV, Im C-NERGY® Super C65 manufactured by Imerys Graphite & Carbon, Ltd. Super P® manufactured by , Ltd., BP2000® manufactured by Cabot Corp., and / or This is LITX(registered trademark) 50 manufactured by Cabot Corp. In some embodiments, one or more of the above types are used. Graphite is commercial, Superior Graphite Co. ABG1010 and / or Superior G Includes ABG1005 manufactured by raphite Co. For example, the anode electrode of a lithium-ion capacitor. The lumen may contain one or more conductivity-enhancing additives described herein. In some embodiments, conductive carbon is present in the electrode film mixture at about 1% by weight. It may be approximately 8% by weight, or approximately 1% to 10% by weight, including approximately 1% to 5% by weight. i. In some embodiments, as described herein, the electrode film is made of conductive carbon By including this, the energy storage device contains approximately 5% more conductive carbon compared to an energy storage device that does not contain conductive carbon. This can result in a % improvement in ESR. In yet another embodiment, the conductive carbon has a surface area of ​​10 ~100m 2 / g, for example 20-50m 2 The characteristic is that the amount is / g and / or the particle size is 0.1 to 10 μm. In another embodiment, the conductive carbon has a particle size of approximately 0.1 μm to approximately 0.5 μm. Alternatively, it is characterized by being about 10 μm. In some embodiments, as shown herein Lithium-ion capacitors with anodes manufactured by this method have an ESR value of approximately 0.1 (m ohm) (milliohm) ~ approximately 10 (m ohm), for example, approximately 0.5 (m ohm) ~ approximately 5 (m ohm), or approximately 1.5 ( The impedance is approximately 3.5 m ohms.

[0035] In some embodiments, one or more electrode films described herein are manufactured in a dry process. It can be manufactured by a manufacturing process. In this specification, the dry manufacturing process is for electrode film This refers to a step in the formation process in which no solvent is used, or is not used, or is not used substantially. For example, the components of the electrode film may include dry particles. By mixing dried particles, a mixture of dried particle electrode films can be obtained. In some embodiments, the electrode film is composed of a weight percentage of the components of the electrode film and dry particles. The electrode film mixture is manufactured using a dry process so that the weight percentages of the components are approximately the same. It can be formed from a mixture of dry particle electrode films. In some embodiments, dry The electrode film formed from the dried particle electrode film mixture through the manufacturing process is a complete and easy-to-use electrode film. It is acceptable if the processing solvent and the resulting solvent residue are not included or substantially not included. In some embodiments, a dry manufacturing process is performed from the dry particle electrode film mixture. The formed electrode film is cleaner and / or structurally stronger. This allows for improved electrochemical and / or mechanical performance. In some embodiments, the electrode film is formed from a dry particle mixture by a dry process. This is a self-supporting dried particle electrode film. In some embodiments, the self-supporting dried electrode film The film is essentially made from dried carbon particles and dried superfibrillated binder particles. In some embodiments, a single fibrillable material such as PTFE is used. Only a single binder is needed to form a self-supporting dry electrode film, such as a binder. It will be used.

[0036] In some embodiments, the energy storage device is not a battery.

[0037] Figure 2 shows an example of a step 200 for manufacturing an electrode film according to several embodiments. This is a flowchart. In some embodiments, step 200 is for manufacturing an electrode film. This is a dry processing step, and the resulting electrode film is free of liquid, solvent, and residue. Or, do not use liquids or solvents that substantially do not contain carbon. In block 202, An electrode film mixture containing elementary particles and a binder material is formed. Optionally, one or more types are used. The above conductivity-enhancing additives can be mixed in. In some embodiments, the electrode phi The lum mixture is a dry particle mixture. In some embodiments, the binder material is polytet One or more materials such as lafluoroethylene (PTFE) and ultra-high molecular weight polyethylene (UHMWPE). It contains a fibrillable polymer. In some embodiments, the binder material is PTFE It consists of, or is essentially, one type of polymer. In some embodiments, The conductivity-enhancing additive may be one or more types of conductive carbon. For example, conductive carbon This includes one or more carbon blacks and / or graphites as described herein. It is possible.

[0038] In block 204, the binder in the electrode film mixture is superfibrillated and superfibrillated A fibrillation matrix can be formed. The superfibrillation process is different from conventional fibril The chemical process can be carried out by performing it at a slow processing speed and / or at a high processing pressure. For example, the process of superfibrillation is described in U.S. Patent Application Publication No. 2015 / 0072234. Compared to other methods, it can be carried out at a reduced speed and / or reduced pressure. Several implementation forms In this case, the superfibrillation process may be a mechanical shearing process. For example, a binder The material can be mechanically processed to form multiple fibrils from the binder material. Mechanical shear force can be applied to the binder material. In some embodiments, Target shearing processes include mixing and / or milling processes. For example, electrode phy The particles of the lum mixture are supplied to the blender and / or mill, and the blender and / or The rate at which the material is circulated through the mill can be reduced during the ultrafibrillation process. Electrode fill This slows down the rate at which the particles of the mixture circulate through the blender and / or mill. Therefore, the particles of the electrode film mixture enter the process chamber of the blender and / or mill. This allows for a longer cycle time. In some embodiments, this cycle time By lengthening the interval, the fibrillation of the binder material is enhanced, resulting in a superfibrillation of the mixture. This can result in a blot. The rate at which particles circulate within the renderer and / or mill is such that they circulate once within the process chamber. The time taken should be set to be approximately 1.2 to 3 times longer than that of conventional dry electrode treatment. This is possible. For example, the mixing and / or grinding time for conventional dry processing is about 1 minute. It is possible. In some embodiments, the mixing and / or grinding time is about 2 minutes, about 3 minutes. The feeding rate for mixing and / or grinding is approximately 4 minutes, 5 minutes, 7 minutes, or 10 minutes. Compared to conventional dry electrode processing, the speed can be reduced to, for example, about half. In the embodiment, the feed rate for mixing and / or grinding is approximately 10% of the feed rate of the rated machine. Approximately 20% of the supply rate for standard machines, approximately 30% of the supply rate for rated machines, and approximately 40% of the supply rate for rated machines. Approximately 50% of the rated machine supply rate, approximately 60% of the rated machine supply rate, approximately 70%, approximately 80% of the rated machine's feed rate, or approximately 90% of the rated machine's feed rate. In one embodiment, the electrode film is dried for about 2 minutes to about 5 minutes. Prepared by a process including a step of mixing and / or grinding for minutes, .

[0039] In some embodiments, continuous mixing can be performed. The mixing and / or grinding time may be inversely proportional to the feeding rate. Therefore, In one embodiment, in order to extend the mixing and / or grinding time, a conventional dry process is used. Compared to the brilling treatment, the supply rate can be reduced. In some embodiments, By reducing this supply rate by half, the mixing and / or grinding time is doubled. Yes. For example, the conventional dry processing feed rate in a particular machine is approximately 50-60 kg / hr. It is possible. Therefore, in some embodiments, the superfibrillation provided herein The binder or matrix can be manufactured in the same machine at a feed rate of approximately 25-30 kg / hr. Yes, it is possible. Generally, this feed rate depends on the milling machine and is described herein. From this perspective, it can be adjusted based on the operating parameters of the machine. Furthermore, other implementations In terms of form, mixing and / or grinding can be done by using larger instruments with larger channels. The time can be extended. When performing batch mixing and / or grinding, The processing time can be extended by performing mixing and / or grinding for a longer period of time. Cut.

[0040] In some embodiments, during the fibrillation process, the process in the blender and / or mill By increasing the processing pressure, superfibrillation can be performed. In some embodiments, the processing pressure As the force increases, the shear force applied to the binder material increases, which in turn increases the binder material The degree of fibrillation increases. In some embodiments, the processing pressure for superfibrillation is... The shear force applied to the alloy is the same as the shear force in the fibrillation treatment of conventional dry electrodes. It can be set to be approximately 1.2 to 3 times the original value.

[0041] Ultrafibrillation treatment performed at slow processing speeds and / or high processing pressures is used for binder materials. This promotes enhanced fibrillation, increasing the number of fibrils formed from the binder material. This may promote an increase in the fibril surface area and / or an increase in the fibril length. In some embodiments, the processing speed is slowed and / or the processing pressure is increased. This enhances fibrillation, allowing for tensile and shear resistance from a small amount of binder material. To form an electrode film having desired resistance to compressive and / or torsional stress. This can be done, for example, by slowing down the processing speed and / or increasing the processing pressure. This reduces the amount of binder material while allowing one or more other components of the film to be used as desired. This can promote the formation of a sufficient amount of fibril to provide mechanical support. In that embodiment, the mixing step of block 202 and the fibrillation step of block 204 are 1 This may be one or substantially one continuous process.

[0042] In certain embodiments, the hyperfibrillation of block 204 is performed in the same manner as the conventional fibrillation process. This can be done by repeating the process two or more times on the same material. The first fibrillation process can form a fibrillated matrix. Next, this fibrillated matrix is ​​reduced in size, for example, the first A powdered electrode film mixture may be formed. For example, block 204 is this first fib The process may include a step of destroying the lylified electrode film mixture. The decomposition process involves straining the fibrillated electrode film mixture through a strainer, shifter, and mesh. This may include passing through a sieve, riddle, screen, and / or sieve. The fibrillated electrode film mixture is then subjected to a second fibril as described herein. It can be superfibrillated by a fibrillation process. This second fibrillation process is described herein. As shown, in fibrillation processes performed at slow processing speeds and / or high processing pressures It is possible. The second fibrillation step may result in a second powdered electrode film mixture. Yes, it is possible. Next, the second powdered electrode film mixture is subjected to further steps of block 204. The iteration may be performed, or the process of block 206 may be carried out. Several implementations In this state, the second (or additional) fibrillation step is performed on the electrode fibrillation enhanced A lum mixture and one or more advantages derived therefrom are provided. Therefore, Block 2 The hyperfibrillation of the binder in 04 involves one, two, three or more fibrillations. This can be done after the sub-process. Finally, in block 204, the ultrafine shown herein A lylized matrix and / or superfibrillated binder particles are obtained.

[0043] In block 206, the fibrillated electrode film mixture is calendered using a calendering apparatus. Therefore, a self-supporting superfibrillated electrode film can be formed. The calendering apparatus This is well known in the relevant technical field, and generally, raw materials such as electrode film mixtures are supplied. It includes a pair of calender rolls for forming an electrode film. In some embodiments, As further described herein, in order to form a film with a desired minimum thickness, Without an additional calendering process, the electrode film is formed in the first calendering process. It is possible. In some embodiments, the calendered mixture is a liquid, solvent. Free-standing, dry particle form that does not contain or substantially contains residues arising therefrom. A film is formed. In some embodiments, the electrode film is formed at the anode electrode film. Yes. In some embodiments, the electrode film is the cathode electrode film. In one embodiment, the superfibrillated electrode film mixture is calendered under selected conditions. - Processing can be performed. For example, in yet another embodiment, the calendar processing is 10-30 It can be done at a temperature of 0°C and a pressure of 5 to 150 kilonewtons. A calendar is a specific type of calendar. The size may be selected for the intended use, but generally, the diameter is in the range of 5 to 80 cm. That's fine. [Examples]

[0044] Figure 3 shows a lithium-ion ion with an anode containing different types of conductivity-enhancing additives. This table shows the equivalent series resistance of each capacitor cell. The type of conductivity-enhancing additive contained in the node and the corresponding equivalent series resistance are related to conductivity enhancement. The improvement is shown as a percentage compared to lithium-ion capacitors that do not contain additives. The conductive additives tested were mesoporous carbon and various types. It contained conductive carbon. As shown in Figure 3, it contained a specific type of conductive carbon. Lithium-ion capacitors equipped with such an anode exhibit improved equivalent series resistance performance. However, lithium-ion capacitors equipped with an anode containing mesoporous carbon are equivalent It did not show any significant improvement in series resistance. For example, it contains a specific type of conductive carbon. A lithium-ion capacitor with an anode has an equivalent series resistance of 5% or more. This showed improvement.

[0045] Furthermore, it contains metal powders such as silver (Ag) powder, nickel (Ni) powder, or copper (Cu) powder. Lithium-ion capacitors equipped with anodes show a significant improvement in equivalent series resistance. I didn't.

[0046] Figure 4 shows a processing step 400 for manufacturing a thin electrode film according to several embodiments. This is a flowchart illustrating an example. In some embodiments, the electrode film is the electrode of the cathode. It can be a film. In some embodiments, the electrode film is the electrode of the anode. It can be made into a film. In some embodiments, for manufacturing an electrode film Step 400 is a dry processing step, and does not use any liquid or solvent, and the resulting electrode film is Free from or substantially free from liquids, solvents, and their residues. Several implementations In this configuration, process 400 is performed to produce an ultracapacitor, battery, and / or lithium It is possible to form electrodes for an ion capacitor.

[0047] Block 402 contains an electrode containing a binder material and one or more conductivity-enhancing additives. The components of the film mixture can be mixed together. In some embodiments, the electrode fill The mixture is a dry particle mixture. The binder material is polytetrafluoroethylene (PTFE). and one or more fibrillable polymers such as ultra-high molecular weight polyethylene (UHMWPE) - may include. In some embodiments, the binder material is one type such as PTFE. It consists of or is essentially a polymer. In some embodiments, the conductivity-enhancing additive is 1 It can be one or more types of conductive carbon. For example, conductive carbon is one of the types described herein. It may contain more than one type of carbon black and / or graphite.

[0048] In block 404, in order to form fibrils from the binder material, an electrode film mixture is used. The compound can be fibrillated. The fibrillation process has a slow processing speed and / or It can be performed under high processing pressure. Its slow processing speed and / or large processing Pressure causes tension, shear, compression, and / or twisting of a small amount of binder material. To enable the formation of electrode films having desired resistance to stress, This may promote the enhancement of brillation. In some embodiments as described herein, Fibrillation treatment is a mechanical shearing treatment, such as mixing and / or grinding treatment. This may include: In some embodiments, the electrode film is mixed during the fibrillation process. This can slow down the rate at which the mixture particles circulate in the blender and / or mill. In some embodiments, the process inside the blender and / or mill during the fibrillation process The pressure can be increased. In some embodiments, the mixing process of block 402 The fibrillation process of block 404 may be one or substantially one continuous process. I. Slowing down the processing speed and / or increasing the processing pressure is more than the above. An electrode film having high strength, for example, less than 120 μm or previously as described herein. Thinner than previously possible, and in a single high-pressure calendering process (single process), or multiple processes. The calendering process (for example, after the first calendering process, the film is fed out) This is done through a process that involves recalculating once or multiple times.

[0049] In a particular embodiment, block 404 is as described with reference to block 204 in Figure 2, The size of the fibrillated electrode film mixture can be changed, for example, by breaking it. The process may include shrinking and then refibrillating. Block 406 includes that The fibrillated electrode film mixture is calendered to form the first electrode film. It is possible to do so. In block 408, the first electrode film can be unwound. For example, The first electrode film is passed through a dispensing machine as shown in Figures 5A and 5B, which are described below. This is possible. In block 410, the unwound electrode film is re-current at least once. It can be treated with a dabbing process. In some embodiments, the electrode film is about 50 μm or less. To form a thin electrode film, such as the thickness or other thinness described herein. It can be recalendered two or more times. In some embodiments, this thin electrode The film provides the desired resistance to tensile, shear, compressive, and / or torsional stresses. This is a self-supporting dry particle electrode film that can be shown. For example, one calendar line. The thickness of the electrode film, such as the anode electrode film of the lithium-ion capacitor that has passed through. The diameter may be approximately 120 μm. The fibrillation obtained as described herein is The electrode film is high-strength, and the calendered electrode film is unwound to approximately 120 μm. The calendar line can be passed one or more times to reach a thickness of less than [amount missing]. For example, the film is subjected to a second calendering process to a thickness of, for example, approximately 80 μm or less. It can be made thinner. The recalendered anode electrode film is fed out. After passing through the calendar line for the third time, it becomes an electrode film with a thickness of approximately 50 μm. can.

[0050] In some embodiments, an electrode film with a thickness of less than 80 μm, or a conventional electrode film, is used. Other electrode films described herein that are thinner than the film are made of ultrafibrillated binders. The electrode film mixture containing the da is manufactured by passing it through a calendar line only once. This is possible. For example, calendar processing can result in increased fibrillation. Due to the high strength of the material, the mixture can be calendered only once to achieve a thickness of less than 80 μm. This can be achieved by applying sufficient pressure to the electrode film mixture. The electrode film mixture is processed only once in a calendering device to obtain the electrode film Making the material thinner will provide a cheaper and / or faster manufacturing process. It is possible.

[0051] Figure 5A is a schematic diagram of one embodiment of a feeder for a calender line of electrode film. Figure 5B is a more detailed view of a part of the feeding mechanism shown in Figure 5A. The apparatus shown can be used to perform the recalendering process 410 in Figure 4. For example, in the illustrated embodiment, a self-supporting drying electrode film (referred to as "feeding material" in Figure 5B) is used. The (as shown) is fed out and then recalendered by the pair of rollers shown in the illustration. A calendar apparatus similar to the rollers shown in Figures 5A and 5B also processes the dry electrode mixture. The material is compressed, and steps such as step 206 in Figure 2 and step 410 in Figure 4 or other embodiments are performed. In the first calendering process, a self-standing dry electrode film can be formed initially. It will be understood that this is possible.

[0052] Figures 6A and 6B show SEM images of the dry electrode film matrix. Figure 6A is This shows an SEM image of a dry electrode film matrix manufactured by a conventional dry electrode processing method. Figure 6B shows the product manufactured according to process 200 and other superfibrillation processes described herein. The fabricated dry electrode film matrix is ​​shown. The electrode film in Figure 6A has an 8% binder. It contains and has a thickness of 80 μm. The electrode film in Figure 6B contains 6.5% binder and 50 It has a thickness of μm. The electrode film in Figure 6B is an electrode film mixture that has undergone two grinding treatments. It was manufactured from a compound. As can be seen from the comparison of Figure 6A and Figure 6B, the dry electrode fill in Figure 6B The Mmatrix is ​​characterized by enhanced fibrillation of the binder. In Figure 6B, the number of fibrils is increasing. In Figure 6A, carbon particles (shown in the figure) The substantial portion of the (which is) has a free surface, and in Figure 6B, the fibrillated binder is carbon grains The substantially increased surface area of ​​the child is covered. Generally, the binder shown in Figure 6B is of the same quality. It has a larger surface area than the binder in Figure 6A, and contacts the carbon particles with a larger surface area. The binder in Figure 6B is an example of a superfibrillated binder provided herein.

[0053] Figure 7 shows various embodiments comprising an anode fabricated by the method described herein. Regarding the lithium-ion capacitor in question, the binder content, film thickness, and electrostatic capacitance The quantity and ESR are shown.

[0054] Although the present invention is disclosed in the context of specific embodiments and examples, those skilled in the art will understand this The invention extends beyond the specifically disclosed embodiments to include other embodiments and / or other uses of the invention. It will be understood that it can be extended to use or modify. In addition, several embodiments of the present invention Although such modifications are shown and described in detail, other modifications within the scope of this invention are permitted. The specific features and characteristics of these embodiments will be readily apparent to those skilled in the art based on the diagram. Various combinations or partial combinations are possible, and this is also within the scope of the present invention. Please understand that it is included in the disclosure. Various features and aspects of the disclosed embodiments are disclosed. To form various other embodiments of the embodiments of the invention, they can be combined with each other, or It should be understood that these can be replaced by each other. Therefore, disclosed herein The scope of the present invention should not be limited by the specific embodiments described above.

[0055] The headings (titles) used herein are for convenience only and do not apply to the information disclosed herein. This does not necessarily affect the scope or meaning of the apparatus and methods.

Claims

1. Self-standing drying containing dried carbon particles and dried superfibrillated binder particles Electrode film and Current collector and An electrode for an energy storage device equipped with the following features.

2. The dry electrode film has a thickness of approximately 50 μm to approximately 120 μm. The electrode described in claim 1.

3. anode The electrode described in claim 1.

4. The above self-standing dry electrode film further contains conductive carbon. The electrode described in claim 1.

5. The electrode film contains approximately 1% to 5% by mass of conductive carbon. The electrode described in claim 1.

6. It is in ionic contact with an electrolyte containing a lithium salt. The electrode described in claim 1.

7. The electrolyte is in further ionic contact with the cathode. The electrode described in claim 5.

8. The above-mentioned dried ultrafibrillated binder particles weigh approximately 5 times the weight of the above-mentioned self-standing dried electrode film. It makes up approximately 7% by weight. The electrode described in claim 1.

9. A lithium-ion capacitor comprising the electrodes described in claim 1.

10. A method for manufacturing a dried electrode film for an energy storage device, A first dry carbon particle containing dry carbon particles and dry fibrillable binder particles A step of forming a dry electrode mixture, The binder in the dried electrode film mixture is superfibrillated, and the electrode film mixture A process of forming a superfibrillated matrix in a material, A mixture of superfibrillated electrode films is calendered to create self-supporting superfibrils. The process of forming a chemical electrode film and A manufacturing method that includes [details omitted].

11. This is a dry process that does not use any processing additives. The manufacturing method described in claim 10.

12. A process of forming a first electrode by bringing a self-supporting electrode film into contact with a current collector. Includes The manufacturing method described in claim 10.

13. The process of forming the second electrode, The process involves inserting a separator between the first electrode and the second electrode. Includes The manufacturing method described in claim 12.

14. The first electrode described above is an anode. The manufacturing method described in claim 12.

15. The above calendering process involves compressing a self-standing dry electrode film to a thickness of approximately 50 μm. Includes a step to reduce the thickness to approximately 120 μm. The manufacturing method described in claim 10.

16. The above process of calendering to a thickness of approximately 50 μm to approximately 120 μm is a single calendering process. Approximately The manufacturing method described in claim 15.

17. The dried superfibrillated binder particles contain approximately 5% to 7% by weight of the above superfibrillated binder. Includes a matrix The manufacturing method described in claim 10.

18. The step of forming the first mixture is to add conductive carbon particles to the first mixture. Further includes The manufacturing method described in claim 10.

19. The first mixture described above contains approximately 1% to 5% by mass of the conductive carbon particles. The manufacturing method described in claim 18.

20. In the manufacturing method described in claim 10, The above process of superfibrillating the binder is, The binder in the dried electrode film mixture is fibrillated to form the first fibrillated matrix. The process of forming the rix, The first fibrillated matrix described above is destroyed, separating carbon particles and fibrillated binder particles. The process of forming a powder mixture with, The above powder mixture is fibrillated to produce a second filament containing the above superfibrillated matrix. A step of forming a dibrylation matrix and A manufacturing method that includes [details omitted].

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