Electrode member for secondary battery and method for manufacturing same

Abstract

Disclosed are: an electrode material for a secondary battery, which can reduce side reactions of lithium, has a simple process, and can reduce cracks caused by external impact; and a method for manufacturing the electrode material. The electrode member for a secondary battery includes a bonding sheet, an active material layer, and a current collector. The adhesive sheet includes a plurality of through-holes penetrating a first surface and a second surface facing each other. The active material layer includes a first layer covering the first surface, a second layer covering the second surface, and a connection layer formed inside the through hole and connecting the first layer and the second layer. The current collector is adhered to the second layer.

Description

Technical Field

[0001] The present invention relates to an electrode member for a secondary battery and a method for manufacturing the same. Background Art

[0002] At present, with the development of the information age, personal mobile electronic devices are being widely used, and these mobile electronic devices necessarily need batteries for driving.

[0003] In the past, primary batteries such as manganese batteries and alkaline batteries were mainly used, which were used once and discarded after discharge. However, secondary batteries that can be recharged after discharge and are therefore reusable are now widely used instead of primary batteries that are disadvantageous in terms of environmental pollution and cost of discarded batteries.

[0004] This type of secondary battery is usually composed of a positive electrode, a negative electrode, an electrolyte and a separator. Among them, the positive electrode and the negative electrode are the core materials that determine the battery capacity, life and charging speed. The positive electrode, as a lithium ion source, determines the battery capacity and average voltage, while the negative electrode determines the charging speed and life.

[0005] In order to manufacture such electrode parts such as positive electrode parts or negative electrode parts, in the "Dry particle-based electrochemical device and its manufacturing method", Korean Publication Patent No. 10-2006-0025230, a dry active material sheet is developed by using a jet mill to perform dry fiberization of fluororesins such as PTFE and PVDF through a high temperature process in order to mix dry active materials and dry binders at room temperature to form a matrix of dry active materials. However, although PTFE has advantages in fiberization to form active material sheets, it increases lithium resistance due to side reactions during lithium charging and discharging.

[0006] To solve this problem, Korean Patent Publication 10-2016-0145043's "Dry Energy Storage Device Electrode and Manufacturing Method Thereof" uses a composite binder containing PTFE and PVDF or a copolymer, and Korean Patent Publication 10-2022-0100240's "Dry Binder, Lithium Secondary Battery Electrode Including the Same and Manufacturing Method Thereof" minimizes the resistance of this lithium by mixing PTFE and CMC or PAA.

[0007] In order to minimize the side reactions of these active materials, PVDF, CMC, PAA, etc. are added to PTFE to suppress the side reactions, but the fiberization structure is not smooth. In other words, although the shear force is strong, this will cause a side reaction of lithium (increase in resistance), resulting in a decrease in battery performance.

[0008] [Prior art literature]

[0009] [Patent Literature]

[0010] Patent document 0001: Korean Publication Patent No. 10-2006-0025230

[0011] Patent document 0002: Korean Publication Patent No. 10-2016-0145043

[0012] Patent document 0003: Korean published patent 10-2022-0100240 Summary of the invention

[0013] Technical issues

[0014] Therefore, the technical problem to be solved by the present invention is to provide an electrode component for a secondary battery and a manufacturing method thereof, which can reduce the side reaction of lithium, have a simple process and can reduce cracks caused by external impact.

[0015] Technical Solution

[0016] An electrode member for a secondary battery of an exemplary embodiment of the present invention for solving this technical problem includes a bonding sheet, an active material layer and a current collector. The bonding sheet includes a plurality of through holes penetrating a first surface and a second surface facing each other. The active material layer includes a first layer covering the first surface, a second layer covering the second surface, and a connecting layer formed inside the through hole to connect the first layer and the second layer. The current collector adheres to the second layer.

[0017] As an embodiment, the bonding sheet may be any one of woven fabric, knit, non-woven fabric, and film.

[0018] As an embodiment, the electrolyte hygroscopicity of the bonding sheet may be in the range of 1.2 cc / g to 1.8 cc / g.

[0019] As an embodiment, the bonding sheet may be cotton, synthetic fiber or a combination thereof.

[0020] As an embodiment, the bonding sheet may include at least any one of polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), polypropylene (PP), polyethylene (PE), polyvinyl chloride (PVC), nylon, cotton, and synthetic fiber.

[0021] As an embodiment, the bonding sheet includes any one of polyvinylidene fluoride (PVDF) or polytetrafluoroethylene (PTFE), and the bonding sheet may be treated with a sodium naphthalene solution.

[0022] As an embodiment, the size of the through hole may be in the range of 1 mm to 10 mm.

[0023] As an embodiment, the thickness of the first layer is the same as that of the second layer, and the ratio of the thickness of the first layer to the thickness of the bonding sheet may be in the range of 0.5:1 or 1:1.

[0024] As an embodiment, the active material layer may include active material particles and a binder.

[0025] As an embodiment, the active material particles may be negative electrode active material particles containing at least any one of carbon, silicon, tin, antimony, and graphene.

[0026] Here, the current collector may be copper foil (Cu).

[0027] As an embodiment, the active material particles may be positive electrode active material particles composed of aluminum (Al), nickel (Ni), titanium (Ti), tungsten (W), iron (Fe), chromium (Cr), alloys thereof, and combinations thereof.

[0028] Here, the current collector may be aluminum foil (Al).

[0029] As an embodiment, the adhesive may include at least any one of polyvinylidene fluoride (PVDF), elastomer, styrene butadiene rubber (SBR), carboxymethylcellulose (CMC), nitrile butadiene rubber (NBR), butadiene, and polyacrylic acid (PAA).

[0030] As an embodiment, when the diameter of the active material particles is less than 10 μm, the size of the through hole may be in the range of 1 mm to 5 mm. When the diameter of the active material particles is 10 μm to 30 μm, the size of the through hole may be in the range of 5 mm to 8 mm.

[0031] As an embodiment, the active material layer may further include conductive material particles dispersed in the binder.

[0032] As an embodiment, the conductive material particles may include at least any one of carbon black, acetylene black, vapor grown carbon fiber (VGCF), carbon nanotube (CNT), and graphene.

[0033] As an embodiment, a bonding layer may be formed between the second layer and the current collector.

[0034] As an embodiment, the bonding layer may be formed by mixing a polymer resin and a conductor, or the bonding layer may be a conductive polymer resin.

[0035] As an embodiment, the polymer resin may include any one of styrene butadiene rubber (SBR), carboxymethylcellulose (CMC), silicone rubber, and butadiene rubber.

[0036] As an embodiment, the electrode member for a secondary battery may further include a protective layer formed on an upper portion of the first layer.

[0037] As an embodiment, the electrode member for a secondary battery may further include a release film adhered to an upper portion of the protective layer.

[0038] As an embodiment, the thickness of the protective layer may be 1 μm to 10 μm.

[0039] As an embodiment, the thickness of the release film may be 2 to 4 times the thickness of the protective layer.

[0040] As an example, the protective layer may include a thermosetting resin or a thermoplastic resin.

[0041] A method for manufacturing an electrode component for a secondary battery according to an exemplary embodiment of the present invention includes: a step of preparing a raw material; a step of preparing an adhesive sheet including a plurality of through holes; a step of impregnating the raw material into a first surface of the adhesive sheet, a second surface opposite to the first surface, and the through holes to form a first layer, a second layer, and a connecting layer connecting the first layer and the second layer; and a step of adhering a release film and a current collector to the first layer and the second layer, respectively.

[0042] As an example, the step of preparing the raw material may include: a step of mixing active material powder and binder powder at high temperature; and a step of pulverizing the agglomerated mixture at room temperature.

[0043] As an example, the step of mixing the active material powder and the binder powder at high temperature may be performed at a temperature ranging from 100°C to 200°C.

[0044] As an embodiment, the active material powder can be a negative electrode active material including at least any one of carbon, silicon, tin, antimony, and graphene, or can be a positive electrode active material including at least any one of aluminum (Al), nickel (Ni), titanium (Ti), tungsten (W), iron (Fe), and chromium (Cr).

[0045] As an embodiment, the adhesive powder may include at least any one of polyvinylidene fluoride (PVDF), elastomer, styrene butadiene rubber (SBR), carboxymethylcellulose (CMC), nitrile butadiene rubber (NBR), butadiene, and polyacrylic acid (PAA).

[0046] As an embodiment, in the step of mixing the active material powder and the binder powder at high temperature, a conductive material powder including at least any one of carbon black, acetylene black (acetylene black), vapor grown carbon fiber (VGCF), carbon nanotube (CNT), and graphene can also be mixed.

[0047] As an embodiment, the bonding sheet may be any one of woven fabric, knit, non-woven fabric, and film.

[0048] As an embodiment, the electrolyte hygroscopicity of the bonding sheet may be in the range of 1.2 cc / g to 1.8 cc / g.

[0049] As an embodiment, the bonding sheet may be cotton, synthetic fiber or a combination thereof.

[0050] As an embodiment, the step of impregnating the raw material into the first surface of the bonding sheet, the second surface opposite to the first surface, and the through hole to form a first layer, a second layer, and a connecting layer connecting the first layer and the second layer includes: the step of placing the raw material between the first roller rotating in the clockwise direction, the second roller adjacent to the first roller and rotating in the counterclockwise direction, the third roller adjacent to the second roller and rotating in the clockwise direction, and the fourth roller adjacent to the third roller and rotating in the counterclockwise direction; and the step of placing the bonding sheet between the second roller and the third roller.

[0051] As an embodiment, the raw material passing between the first roller and the second roller can adhere to the surface of the second roller and rotate to adhere to the first side of the bonding sheet, and the raw material passing between the third roller and the fourth roller can adhere to the surface of the third roller and rotate to adhere to the second side of the bonding sheet.

[0052] As an embodiment, the surfaces of the second roller and the third roller may be formed to be rougher than those of the first roller and the fourth roller.

[0053] As an embodiment, a coating for preventing the raw material from adhering may be formed on the surfaces of the first roller and the fourth roller.

[0054] As an embodiment, the step of adhering a release film and a current collector to the first layer and the second layer respectively may include: a step of coating a first adhesive on the surface of the release film; a step of coating a second adhesive on the surface of the current collector or the second layer; and a step of rolling the release film, the adhesive sheet impregnated with the raw material substance, and the current collector.

[0055] As an embodiment, the first binder may include a thermosetting resin or a thermoplastic resin, the second binder may be a mixture of a polymer resin and a conductor, or the second binder may be a conductive polymer resin, and the polymer resin includes any one of styrene butadiene rubber (SBR), carboxymethylcellulose (CMC), silicone rubber, and butadiene rubber.

[0056] As an embodiment, the thickness of the first adhesive may be 1 μm to 10 μm.

[0057] As an embodiment, the thickness of the release film may be 2 to 4 times the thickness of the first adhesive.

[0058] A method for manufacturing an electrode component for a secondary battery according to an exemplary embodiment of the present invention includes: a step of mixing active material powder and adhesive powder at high temperature; a step of crushing the agglomerated mixture at room temperature to form a raw material; a step of impregnating the raw material into a first surface of an adhesive sheet including a plurality of through holes, a second surface opposite to the first surface, and the through holes to form a first layer, a second layer, and a connecting layer connecting the first layer and the second layer; a step of coating a first adhesive on the surface of a release film; a step of coating a second adhesive on the surface of the current collector or the second layer; and a step of rolling the release film, the adhesive sheet impregnated with the raw material, and the current collector.

[0059] Effects of the Invention

[0060] According to the electrode member for secondary battery and the manufacturing method thereof of the present invention as described above, the film-type adhesive sheet replaces the existing dry powder-type adhesive to play the role of adhesive. That is, the adhesive sheet plays the role of bonding for the expansion and contraction during the charging and discharging process of lithium. Therefore, the manufacturing process can be simplified and cracks caused by external impact can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] Figure 1 is a cross-sectional view of an electrode member for a secondary battery according to an exemplary embodiment of the present invention;

[0062] Figure 2 for Figure 1 Actual photograph of the electrode member for a secondary battery shown;

[0063] Figure 3 To show Figure 1 A flowchart of a method for manufacturing an electrode member for a secondary battery shown in FIG.

[0064] Figure 4 To show Figure 3 A flowchart of an embodiment of step S110 is shown;

[0065] Figure 5 To show Figure 3 A flowchart of an embodiment of step S130 is shown;

[0066] Figure 6 To show Figure 5 A conceptual diagram of the process;

[0067] Figure 7 To show Figure 3 A flowchart of an embodiment of step S140 is shown;

[0068] Figure 8 To show Figure 7 A conceptual diagram of the process of step S143 is shown.

[0069] Description of Reference Numerals

[0070] 1000: Electrode parts for secondary batteries

[0071] 1100: bonding sheet 1110: active material particles

[0072] 1120: Adhesive 1130: Conductive material particles

[0073] 1100a: first surface 1100b: second surface

[0074] 1200: Current collector 1300: Adhesive layer

[0075] 1400: Protective layer 1500: Release film

[0076] 1600: Active material layer 1610: First layer

[0077] 1620: Second layer 1630: Connection layer

[0078] TH: Through hole

[0079] R1: First roller R2: Second roller

[0080] R3: The third roller R4: The fourth roller DETAILED DESCRIPTION

[0081] The present invention is susceptible of numerous variations and forms, and therefore specific embodiments are shown in the drawings and described in detail in the text. However, it should be understood that this is not intended to limit the present invention to a particular disclosed form, but rather to include all variations, equivalents, and even substitutes included in the spirit and technical scope of the present invention. Similar reference numerals are used for similar constituent elements in the description of the various figures. The dimensions of the components in the drawings may be shown larger than actual dimensions in order to clearly illustrate the present invention.

[0082] The terms first, second, etc. can be used to describe various constituent elements, but the constituent elements should not be limited by these terms. The terms are only used to distinguish one constituent element from other constituent elements. For example, without departing from the scope of the present invention, the first constituent element can be named as the second constituent element, and similarly, the second constituent element can also be named as the first constituent element.

[0083] The terms used in this application are only used to describe specific embodiments and are not intended to limit the present invention. Unless the context clearly indicates otherwise, singular expressions include plural expressions. It should be understood that in this application, terms such as "including" or "having" are intended to indicate the presence of features, numbers, steps, operations, constituent elements, parts or combinations thereof described in the specification, without excluding in advance the existence or additional possibilities of one or more other features, numbers, steps, operations, constituent elements, parts or combinations thereof. Moreover, the meaning of "connection" and "combination" of A and B includes not only the direct connection or combination of A and B, but also the situation where A and B include other constituent elements C to connect or combine A and B.

[0084] Unless otherwise defined, all terms used herein, including technical terms and scientific terms, have the same meaning as those generally understood by ordinary technicians in the technical field to which the present invention belongs. Terms defined in commonly used dictionaries should be interpreted as having the same meaning as in the context of the relevant technology, and unless clearly defined in this application, they are not interpreted as ideal or overly formal meanings. In addition, in the claims about method inventions, the order of each step can be changed unless each step is explicitly subject to order constraints.

[0085] Furthermore, the configurations described separately in each embodiment may also be applied to other embodiments.

[0086] The embodiments of the present invention are described in more detail below with reference to the accompanying drawings.

[0087] Figure 1 is a cross-sectional view of an electrode member for a secondary battery according to an exemplary embodiment of the present invention, Figure 2 for Figure 1 An actual photograph of an electrode member for a secondary battery is shown.

[0088] Reference Figure 1 , an electrode member 1000 for a secondary battery according to an exemplary embodiment of the present invention includes a bonding sheet 1100 , an active material layer 1600 , and a current collector 1200 .

[0089] The bonding sheet 1100 includes a plurality of through holes TH that penetrate the first surface 1100a and the second surface 1100b that face each other. As an embodiment, the bonding sheet 1100 may be any one of a woven fabric, a knit, a non-woven fabric, and a film. As described above, when a cloth-type material with good hygroscopicity is used as the bonding sheet 1100, it is easy to absorb moisture from the electrolyte of the secondary battery, so that lithium ions are easily embedded and de-embedded. Therefore, the performance of the electrode component can be improved. As an embodiment, the electrolyte hygroscopicity of the bonding sheet 1100 may be in the range of 1.2cc / g to 1.8cc / g.

[0090] Moreover, the above-mentioned bonding sheet 1100 can prevent the active material particles inside the active material layer 1600 from being damaged during the rolling process. In particular, the active material particles of the positive electrode are more easily damaged than the active material particles of the negative electrode during the rolling process, and the bonding sheet 1100 acts as a buffer to prevent the active material particles from being damaged.

[0091] As an embodiment, the bonding sheet 1100 may be cotton, synthetic fiber or a combination thereof.

[0092] As an embodiment, the bonding sheet 1100 can be at least any one of polyvinylidenefluoride (PVDF), polytetrafluoroethylene (PTFE), polypropylene (PP), polyethylene (PE), polyvinyl chloride (PVC), nylon, cotton, and synthetic fiber.

[0093] As an embodiment, the bonding sheet 1100 includes any one of polyvinylidene fluoride (PVDF) or polytetrafluoroethylene (PTFE), and the bonding sheet can be treated with a sodium naphthalene solution. As described above, when the sodium series liquid is sprayed, the heterogeneous bonding force can be increased by modifying the surface of the fluoropolymer including the non-sticky material PTFE, PFA, FEP, ETFE, PCTFE, PVDF.

[0094] On the other hand, the size of the through hole TH may be in the range of 1 mm to 10 mm. Preferably, when the diameter of the active material particles to be described later is less than 10 μm, the size of the through hole may be in the range of 1 mm to 5 mm, and when the diameter of the active material particles is 10 μm to 30 μm, the size of the through hole may be in the range of 5 mm to 8 mm.

[0095] The active material layer 1600 includes: a first layer 1610 covering the first surface 1100a, a second layer 1620 covering the second surface 1100b, and a connection layer 1630 formed inside the through hole TH to connect the first layer 1610 and the second layer 1620. As described above, the connection layer 1630 connects the first layer 1610 and the second layer 1620, so that the first layer 1610 and the second layer 1620 can be more strongly fastened to the bonding sheet 1100.

[0096] As an embodiment, the first layer 1610 and the second layer 1620 have the same thickness, and the ratio of the thickness of the first layer 1610 to the thickness of the bonding sheet 1100 may be in the range of 0.5:1 or 1:1. If the thickness of the first layer 1610 or the second layer 1620 is too thin, the efficiency is reduced, and conversely, if it is too thick, it may break.

[0097] As an embodiment, the active material layer 1600 may include active material particles 1110 and a binder 1120. Moreover, as an embodiment, the active material layer 1600 may further include conductive material particles 1130 dispersed in the binder 1120.

[0098] As an embodiment, the active material particles 1110 may be negative electrode active material particles including at least any one of carbon, silicon, tin, antimony, and graphene. In this case, the current collector 1200 may be copper foil (Cu).

[0099] As an embodiment, the active material particles 1110 may be positive electrode active material particles composed of aluminum (Al), nickel (Ni), titanium (Ti), tungsten (W), iron (Fe), chromium (Cr), alloys thereof, and combinations thereof. In this case, the current collector 1200 may be aluminum foil (Al).

[0100] As an embodiment, the adhesive 1120 may include at least any one of polyvinylidene fluoride (PVDF), elastomer, styrene butadiene rubber (SBR), carboxymethylcellulose (CMC), nitrile butadiene rubber (NBR), butadiene, and polyacrylic acid (PAA).

[0101] As an embodiment, the conductive material particles 1130 may include at least any one of carbon black, acetylene black, vapor grown carbon fiber (VGCF), carbon nanotube (CNT), and graphene.

[0102] The current collector 1200 is adhered to the second layer 1620. To this end, a bonding layer 1300 may be formed between the second layer and the current collector.

[0103] As an embodiment, the bonding layer 1300 may be formed by mixing a polymer resin with a conductor, or the bonding layer 1300 may be a conductive polymer resin. As an embodiment, the polymer resin may include any one of styrene butadiene rubber (SBR), carboxymethylcellulose (CMC), silicone rubber, and butadiene rubber.

[0104] On the other hand, the electrode member 1000 for a secondary battery may further include a protective layer 1400 formed on an upper portion of the first layer 1610 .

[0105] As an embodiment, the electrode member 1000 for a secondary battery may further include a release film 1500 adhered to the upper portion of the protective layer 1400. For example, a cheap PET film may be used as the release film 1500. In the case where the release film 1500 is provided to a secondary battery manufacturer and the release film 1500 is removed by the secondary battery manufacturer, since the adhesion of PET is low, only the release film 1500 may be easily removed without peeling off the protective layer 1400.

[0106] The protective layer 1400 protects the surface of the first layer 1610. In the case of forming the active material layer 1600 by a wet process, after the binder is completely dissolved by the solvent and the solvent is evaporated, the binder 1120 bonds the active material particles 1110 and the conductive material particles 1130, so the binder 1120 completely surrounds the active material particles 1110 and the conductive material particles 1130, and thus the bonding force between the particles is enhanced.

[0107] However, as in the case of the present invention being carried out by a dry process, the binder powder is partially melted by heat and then dried, so the active material layer 1600 is relatively fragile compared to the wet process. In particular, the active material layer 1600 is exposed to the electrolyte inside the secondary battery, so it becomes more fragile and can be easily damaged.

[0108] In order to solve this problem, in the present invention, the protective layer 1400 covers the first layer 1610 constituting the active material layer 1600 to protect it.

[0109] As an embodiment, the thickness of the protective layer 1400 may be 1 μm to 10 μm. If the protective layer 1400 is too thin, the protection of the first layer 1610 is weak, while if it is too thick, the electrolyte of the secondary battery is difficult to penetrate, so the electrode component cannot function normally.

[0110] On the other hand, the thickness of the release film 1500 may be 2 to 4 times the thickness of the protective layer 1400. If the release film 1500 is too thick, the bonding force between the protective layer 1400 and the first layer 1610 decreases during the rolling process in the manufacturing process to be described later. In more detail, in order to control the thickness of the protective layer 1400, the protective layer 1400 is not directly formed on the first layer 1610, but after being coated on the release film 1500 for pre-curing, the release film 1500 is pressed to transfer the protective layer 1400 from the release film 1500 to the upper part of the first layer 1610. Here, the release film 1500 made of elastic material absorbs the pressing of the roller, so the protective layer 1400 is not pressed to the first layer 1610.

[0111] On the other hand, the protective layer 1400 may include a thermosetting resin or a thermoplastic resin. As an embodiment, the protective layer 1400 may be formed of a thermosetting epoxy resin.

[0112] exist Figure 2 In the embodiment, gauze is used as the bonding sheet 1100, and it can be confirmed that a first layer 1610 is formed on the gauze.

[0113] Figure 3 To show Figure 1 Flow chart of a method for manufacturing an electrode member for a secondary battery shown in FIG.

[0114] Reference Figure 3 According to an exemplary embodiment of the present invention, a method for manufacturing an electrode component for a secondary battery includes: a step S110 of preparing a raw material; a step S120 of preparing a bonding sheet including a plurality of through holes; a step S130 of impregnating the raw material into a first surface of the bonding sheet, a second surface opposite to the first surface, and the through holes to form a first layer, a second layer, and a connecting layer connecting the first layer and the second layer; and a step S140 of respectively adhering a release film and a current collector to the first layer and the second layer.

[0115] The order of the step S110 of preparing the raw material and the step S120 of preparing the bonding sheet including a plurality of through holes may be interchanged or performed simultaneously.

[0116] Below, each step is described in more detail.

[0117] Figure 4 To show Figure 3 FIG. 1 is a flow chart of an embodiment of step S110 shown in FIG.

[0118] Reference Figure 3 and Figure 4, the step of preparing the raw material material S110 may include: a step of mixing the active material powder and the binder powder at high temperature S111; and a step of crushing the agglomerated mixture at room temperature S112. On the other hand, in the step of mixing the active material powder and the binder powder at high temperature, a conductive material powder may be further mixed, and the conductive material powder may include at least any one of carbon black, acetylene black (acetylene black), vapor grown carbon fiber (Vapor grown carbon fiber, VGCF), carbon nanotube (CNT), and graphene.

[0119] As an embodiment, the step S111 of mixing the active material powder and the binder powder at high temperature can be performed at a temperature range of 100° C. to 200° C. At the high temperature, the binder partially melts and adheres to the particles of the active material powder and the conductive material particles to form a mass, which is then crushed to form a raw material, and then put into the reference Figure 6 The active material powder, the conductive material powder, and the binder powder may be mixed and put into the roller, but the following is done. Figure 4 In the process shown, the conductive material and the binder are pre-bonded to a certain extent, so the bonding force to the pores can be enhanced compared to injecting the active material powder, the conductive material powder, and the binder powder into the pores in a mixed state.

[0120] As described above, as an embodiment, the active material powder can be a negative electrode active material including at least any one of carbon, silicon, tin, antimony, and graphene, or can be a positive electrode active material including at least any one of aluminum (Al), nickel (Ni), titanium (Ti), tungsten (W), iron (Fe), and chromium (Cr).

[0121] Furthermore, the binder powder may include at least any one of polyvinylidene fluoride (PVDF), elastomer, styrene butadiene rubber (SBR), carboxymethylcellulose (CMC), nitrile butadiene rubber (NBR), butadiene, and polyacrylic acid (PAA).

[0122] Moreover, as described above, the bonding sheet can be any one of woven fabric, knit, non-woven fabric, and film. As an embodiment, the electrolyte hygroscopicity of the bonding sheet can be in the range of 1.2cc / g to 1.8cc / g. As an embodiment, the bonding sheet can be cotton, synthetic fiber, or a combination thereof.

[0123] Figure 5 To show Figure 3 FIG. 1 is a flow chart of an embodiment of step S130 shown in FIG.

[0124] Reference Figure 3 and Figure 5 The step S130 of impregnating the raw material into the first surface of the bonding sheet, the second surface facing the first surface, and the through hole to form the first layer, the second layer, and the connecting layer connecting the first layer and the second layer includes: step S131 of throwing the raw material between the first roller rotating in the clockwise direction, the second roller adjacent to the first roller and rotating in the counterclockwise direction, the third roller adjacent to the second roller and rotating in the clockwise direction, and the fourth roller adjacent to the third roller and rotating in the counterclockwise direction; and step S132 of throwing the bonding sheet between the second roller and the third roller. Here, the order of the steps S131 and S132 can be interchanged or performed simultaneously.

[0125] Here, the raw material passing between the first roller and the second roller can adhere to the surface of the second roller and rotate to adhere to the first side of the bonding sheet, and the raw material passing between the third roller and the fourth roller can adhere to the surface of the third roller and rotate to adhere to the second side of the bonding sheet.

[0126] Below, refer to Figure 6 The above process is explained in more detail.

[0127] Figure 6 To show Figure 5 Conceptual diagram of the process.

[0128] Reference Figure 6 The device for performing step S130 of impregnating the raw material into the first surface of the bonding sheet and the second surface facing the first surface to form the first layer and the second layer includes four rollers.

[0129] The first roller R1 rotates, for example, in a clockwise direction. The second roller R2 is disposed adjacent to the first roller R1 and rotates, for example, in a counterclockwise direction. The third roller R3 is disposed adjacent to the second roller R2 and rotates, for example, in a clockwise direction. The fourth roller R4 is disposed adjacent to the third roller R3 and rotates, for example, in a counterclockwise direction.

[0130] will pass Figure 4 The raw material manufactured by the process is put between the first roller R1 and the second roller R2 and between the third roller R3 and the fourth roller R4. Here, the first roller R1, the second roller R2, the third roller R3 and the fourth roller R4 are at high temperatures, and the adhesive 1120 of the raw material is partially melted and discharged from between the rollers in the form of a sheet.

[0131] On the other hand, a sheet manufactured by feeding a raw material between the first roller R1 and the second roller R2 adheres to the surface of the second roller R2 and rotates with the second roller R2. Similarly, a sheet manufactured by feeding a raw material between the third roller R3 and the fourth roller R4 adheres to the surface of the third roller R3 and rotates with the third roller R3.

[0132] Here, the bonding sheet 1100 is dropped between the second roller R2 and the third roller R3 from the bottom, and the raw material sheets adhered to the surfaces of the second roller R2 and the third roller R3 are combined with the bonding sheet 1100 as they come out of the second roller R2 and the third roller R3 .

[0133] In order to allow the raw material sheet to adhere to the surfaces of the second roller R2 and the third roller R3 as described above, the surfaces of the second roller and the third roller may be formed to be rougher than the first roller and the fourth roller. In addition, as an embodiment, the surfaces of the first roller and the fourth roller may be formed with a coating that prevents the raw material from adhering.

[0134] Figure 7 To show Figure 3 The flowchart of one embodiment of step S140 is shown in FIG. Figure 8 To show Figure 7 A conceptual diagram of the process of step S143 is shown.

[0135] Reference Figure 3 and Figure 7 , the step S140 of respectively adhering a release film and a current collector to the first layer and the second layer may include: a step S141 of coating a first adhesive on the surface of the release film; a step S142 of coating a second adhesive on the surface of the current collector or the second layer; and a step S143 of rolling the release film, the adhesive sheet impregnated with the raw material substance, and the current collector.

[0136] As an embodiment, the first binder includes a thermosetting resin or a thermoplastic resin, the second binder can be a mixture of a polymer resin and a conductor, or the second binder can be a conductive polymer resin, and the polymer resin includes any one of styrene butadiene rubber (SBR), carboxymethylcellulose (CMC), silicone rubber, and butadiene rubber.

[0137] The first adhesive thus produced has the following effect after curing: Figure 1 The second adhesive has the function of protecting the layer 1400 after curing. Figure 1 Function of the bonding layer 1300 .

[0138] As an embodiment, the thickness of the first adhesive may be 1 μm to 10 μm. As described above, the first adhesive is not applied to the first layer, but is applied to the release film and then adhered to the first layer after semi-curing and then fully cured, in order to control the thickness of the first adhesive. That is, the surface of the first layer may have a plurality of grooves formed on the surface, and may also have concave-convex, so even if a certain amount of adhesive is applied, it will be absorbed by the first layer, so it is not easy to adjust the thickness. Therefore, in the present invention, the first adhesive is applied to the release film with a smooth surface.

[0139] Afterwards, if Figure 8 As shown, by rolling, the first binder and the second binder are solidified by applying pressure to the current collector and the release film with a roller. On the other hand, as described above, the thickness of the release film can be 2 to 4 times the thickness of the first binder. If the release film is too thick, the roller pressure cannot be effectively transmitted due to the large buffering effect of the release film.

[0140] According to the electrode member for secondary battery and the manufacturing method thereof of the present invention as described above, the film-type adhesive sheet replaces the existing dry powder-type adhesive to play the role of adhesive. That is, the adhesive sheet plays the role of bonding for the expansion and contraction during the charging and discharging process of lithium. Therefore, the manufacturing process can be simplified and cracks caused by external impact can be reduced.

[0141] Although the detailed description of the present invention described above has been described with reference to the preferred embodiments of the present invention, a person skilled in the art or an ordinary person in the art will understand that various modifications and changes may be made to the present invention without departing from the scope of the idea and technical field of the present invention as described in the appended claims.

Claims

1. An electrode member for a secondary battery, comprising: The bonding sheet includes a plurality of through holes penetrating through a first surface and a second surface facing each other; The active material layer includes a first layer covering the first surface, a second layer covering the second surface, and a connecting layer formed inside the through hole to connect the first layer and the second layer; as well as A current collector is adhered to the second layer.

2. The electrode member for a secondary battery according to claim 1, characterized in that: The bonding sheet is any one of woven fabric, knitted fabric, non-woven fabric and film.

3. The electrode member for a secondary battery according to claim 2, characterized in that: The electrolyte hygroscopicity of the bonding sheet is in the range of 1.2 cc / g to 1.8 cc / g.

4. The electrode member for a secondary battery according to claim 2, characterized in that: The bonding sheet is made of cotton, synthetic fiber or a combination thereof.

5. The electrode member for a secondary battery according to claim 1, characterized in that: The bonding sheet comprises at least any one of polyvinylidene fluoride, polytetrafluoroethylene, polypropylene, polyethylene, polyvinyl chloride, nylon, cotton, and synthetic fibers.

6. The electrode member for a secondary battery according to claim 1, characterized in that: The bonding sheet comprises any one of polyvinylidene fluoride or polytetrafluoroethylene, The bonding sheet is treated with a sodium naphthalene solution.

7. The electrode member for a secondary battery according to claim 1, characterized in that: The size of the through hole is in the range of 1 mm to 10 mm.

8. The electrode member for a secondary battery according to claim 1, characterized in that: The first layer and the second layer have the same thickness, and the ratio of the thickness of the first layer to the thickness of the bonding sheet is in the range of 0.5:1 or 1:

1.

9. The electrode member for a secondary battery according to claim 1, characterized in that: The active material layer includes active material particles and a binder.

10. The electrode member for a secondary battery according to claim 9, characterized in that: The active material particles are negative electrode active material particles containing at least any one of carbon, silicon, tin, antimony, and graphene.

11. The electrode member for a secondary battery according to claim 10, characterized in that: The current collector is copper foil.

12. The electrode member for a secondary battery according to claim 9, characterized in that: The active material particles are positive electrode active material particles composed of aluminum, nickel, titanium, tungsten, iron, chromium, alloys thereof, and combinations thereof.

13. The electrode member for a secondary battery according to claim 12, characterized in that: The current collector is aluminum foil.

14. The electrode member for a secondary battery according to claim 9, characterized in that: The binder includes at least any one of polyvinylidene fluoride, elastomer, styrene-butadiene rubber, carboxymethyl cellulose, nitrile rubber, butadiene, and polyacrylic acid.

15. The electrode member for a secondary battery according to claim 9, characterized in that: When the diameter of the active material particles is 10 μm or less, the size of the through holes is in the range of 1 mm to 5 mm. When the diameter of the active material particles is 10 μm to 30 μm, the size of the through holes is in the range of 5 mm to 8 mm.

16. The electrode member for a secondary battery according to claim 9, characterized in that: The active material layer further includes conductive material particles dispersed in the binder.

17. The electrode member for a secondary battery according to claim 16, characterized in that: The conductive material particles include at least any one of carbon black, acetylene black, vapor-grown carbon fiber, carbon nanotubes, and graphene.

18. The electrode member for a secondary battery according to claim 1, characterized in that: A bonding layer is formed between the second layer and the current collector.

19. The electrode member for a secondary battery according to claim 18, characterized in that: The adhesive layer is formed by mixing a polymer resin and a conductor, or the adhesive layer is a conductive polymer resin.

20. The electrode member for a secondary battery according to claim 19, characterized in that: The polymer resin includes any one of styrene-butadiene rubber, carboxymethyl cellulose, silicone rubber and butadiene rubber.

21. The electrode member for a secondary battery according to claim 1, characterized in that: A protective layer is formed on an upper portion of the first layer.

22. The electrode member for a secondary battery according to claim 21, characterized in that: The protective layer further comprises a release film adhered to the upper portion of the protective layer.

23. The electrode member for a secondary battery according to claim 22, characterized in that: The thickness of the protective layer is 1 μm to 10 μm.

24. The electrode member for a secondary battery according to claim 23, characterized in that: The thickness of the release film is 2 to 4 times the thickness of the protective layer.

25. The electrode member for a secondary battery according to claim 21, characterized in that: The protective layer includes a thermosetting resin or a thermoplastic resin.

26. A method for manufacturing an electrode member for a secondary battery, comprising: Steps for preparing raw materials; a step of preparing a bonding sheet including a plurality of through holes; The step of impregnating the raw material into the first surface of the bonding sheet, the second surface facing the first surface, and the through hole to form a first layer, a second layer, and a connecting layer connecting the first layer and the second layer; as well as The step of respectively adhering a release film and a current collector to the first layer and the second layer.

27. The method for manufacturing an electrode member for a secondary battery according to claim 26, characterized in that: The steps for preparing the feedstock material include: a step of mixing active material powder and binder powder at high temperature; and A step of pulverizing the agglomerated mixture at room temperature.

28. The method for manufacturing an electrode member for a secondary battery according to claim 27, characterized in that: The step of mixing the active material powder and the binder powder at a high temperature is performed in a temperature range of 100°C to 200°C.

29. The method for manufacturing an electrode member for a secondary battery according to claim 27, characterized in that: The active material powder is a negative electrode active material containing at least any one of carbon, silicon, tin, antimony, and graphene, or a positive electrode active material containing at least any one of aluminum, nickel, titanium, tungsten, iron, and chromium.

30. The method for manufacturing an electrode member for a secondary battery according to claim 27, characterized in that: The binder powder includes at least any one of polyvinylidene fluoride, elastomer, styrene-butadiene rubber, carboxymethyl cellulose, nitrile rubber, butadiene, and polyacrylic acid.

31. The method for manufacturing an electrode member for a secondary battery according to claim 27, characterized in that: In the step of mixing the active material powder and the binder powder at high temperature, a conductive material powder including at least any one of carbon black, acetylene black, vapor-grown carbon fiber, carbon nanotube, and graphene is also mixed.

32. The method for manufacturing an electrode member for a secondary battery according to claim 26, characterized in that: The bonding sheet is any one of woven fabric, knitted fabric, non-woven fabric and film.

33. The method for manufacturing an electrode member for a secondary battery according to claim 26, characterized in that: The electrolyte hygroscopicity of the bonding sheet is in the range of 1.2 cc / g to 1.8 cc / g.

34. The method for manufacturing an electrode member for a secondary battery according to claim 26, characterized in that: The bonding sheet is made of cotton, synthetic fiber or a combination thereof.

35. The method for manufacturing an electrode member for a secondary battery according to claim 26, characterized in that: The step of impregnating the raw material into the first surface of the bonding sheet, the second surface facing the first surface, and the through hole to form a first layer, a second layer, and a connecting layer connecting the first layer and the second layer comprises: The step of feeding the raw material into a first roller rotating in a clockwise direction, a second roller adjacent to the first roller and rotating in a counterclockwise direction, a third roller adjacent to the second roller and rotating in a clockwise direction, and a fourth roller adjacent to the third roller and rotating in a counterclockwise direction, between the first roller and the second roller and between the third roller and the fourth roller; and A step of inserting an adhesive sheet between the second roller and the third roller.

36. The method for manufacturing an electrode member for a secondary battery according to claim 35, characterized in that: The raw material passed between the first roller and the second roller adheres to the surface of the second roller and rotates to adhere to the first surface of the bonding sheet. The raw material that has passed between the third roller and the fourth roller adheres to the surface of the third roller and rotates to adhere to the second surface of the bonding sheet.

37. The method for manufacturing an electrode member for a secondary battery according to claim 35, characterized in that: The surfaces of the second roller and the third roller are formed to be rougher than those of the first roller and the fourth roller.

38. The method for manufacturing an electrode member for a secondary battery according to claim 35, characterized in that: A coating for preventing the raw material from adhering is formed on the surfaces of the first roller and the fourth roller.

39. The method for manufacturing an electrode member for a secondary battery according to claim 26, characterized in that: The steps of respectively adhering a release film and a current collector to the first layer and the second layer include: The step of coating a first adhesive on the surface of the release film; A step of coating a second binder on the surface of the current collector or the second layer; and The release film, the bonding sheet impregnated with the raw material substance and the current collector are roll-pressed.

40. The method for manufacturing an electrode member for a secondary battery according to claim 39, wherein: The first binder includes a thermosetting resin or a thermoplastic resin, The second binder is formed by mixing a polymer resin and a conductor, or the second binder is a conductive polymer resin, and the polymer resin includes any one of styrene-butadiene rubber, carboxymethyl cellulose, silicone rubber, and butadiene rubber.

41. The method for manufacturing an electrode member for a secondary battery according to claim 39, characterized in that: The thickness of the first adhesive is 1 μm to 10 μm.

42. The method for manufacturing an electrode member for a secondary battery according to claim 41, characterized in that: The thickness of the release film is 2 to 4 times the thickness of the first adhesive.

43. A method for manufacturing an electrode member for a secondary battery, comprising: a step of mixing active material powder and binder powder at high temperature; A step of pulverizing the agglomerated mixture at room temperature to form a raw material; The step of impregnating the raw material into a first surface of an adhesive sheet including a plurality of through holes, a second surface facing the first surface, and the through holes to form a first layer, a second layer, and a connecting layer connecting the first layer and the second layer; The step of coating a first adhesive on the surface of the release film; A step of coating a second binder on the surface of the current collector or the second layer; as well as The release film, the bonding sheet impregnated with the raw material substance and the current collector are roll-pressed.

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