Current collector comprising conductive primer layer and all-solid-state battery comprising same

Abstract

Disclosed is a current collector having a primer layer containing a conductive material and a binder having a three-dimensional network structure, an electrode for an all-solid-state battery including the current collector, an all-solid-state battery including the current collector, and a method of manufacturing an electrode for an all-solid-state battery.

Description

[0001] Cross-reference to related applications

[0002] This application claims priority to Korean Patent Application No. 10-2024-0154679, filed with the Korean Intellectual Property Office on November 4, 2024, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present invention relates to a current collector having a primer layer disposed on one surface of a substrate, the primer layer comprising a conductive material and an adhesive having a three-dimensional network structure to maximize its adhesion to an electrode layer, thereby improving the performance and durability of an all-solid-state battery. The present invention also relates to an electrode for an all-solid-state battery comprising the current collector, and an all-solid-state battery comprising the electrode. Background Technology

[0004] All-solid-state batteries offer advantages in ensuring high energy density and safety, making them a promising alternative to existing lithium-ion batteries. However, since all-solid-state batteries use a solid electrolyte, minimizing the resistance at the interface between the current collector and the electrode layer, as well as at the interface between the electrode layer and the solid electrolyte layer, is essential for improving battery performance. In particular, the low adhesion at the interface between the current collector and the electrode layer can lead to the easy detachment of solid particles from the electrode during manufacturing, and the reduced contact area during repeated charge-discharge cycles can cause an increase in interfacial resistance. These issues can have a greater adverse impact during continuous charge-discharge cycles, reducing the movement paths of electrons and ions, decreasing charge-discharge efficiency, and potentially rapidly degrading the overall battery durability, significantly reducing the electrochemical performance of all-solid-state batteries.

[0005] Therefore, a novel current collector design is needed that can maximize the adhesion force at the interface between the electrode layer and the current collector while maintaining the unique properties of the current collector. Summary of the Invention

[0006] The present invention aims to solve the above-mentioned problems existing in the prior art, while retaining the advantages achieved by the prior art.

[0007] One aspect of the present invention provides a current collector capable of solving the above-mentioned problems, an electrode for an all-solid-state battery including the current collector, and an all-solid-state battery including the electrode.

[0008] More specifically, the present invention provides a current collector comprising a primer layer disposed on one surface of a substrate, the primer layer comprising a conductive material and an adhesive having a three-dimensional network structure to maximize the adhesion between the primer layer and the electrode layer and minimize volume changes during charge / discharge, thereby minimizing the degradation of the durability of the electrodes and the all-solid-state battery.

[0009] The technical problems to be solved by the present invention are not limited to those described above. Any other technical problems not mentioned herein will be clearly understood by those skilled in the art from the following description.

[0010] To achieve the objective, (1) the present invention provides a current collector comprising: a substrate; and a primer layer disposed on the substrate, wherein the primer layer comprises a conductive material and an adhesive having a three-dimensional network structure, wherein the adhesive having a three-dimensional network structure comprises crosslinking between a polymer having unsaturated bonds and a vulcanizing agent.

[0011] (2) The present invention provides the current collector of (1), wherein the conductive material is a spherical conductive material.

[0012] (3) The present invention provides a current collector of (1) or (2), wherein the BET specific surface area of ​​the conductive material is about 50 m². 2 / g or greater and approximately 100m 2 / g or less.

[0013] (4) The present invention provides a current collector of any one of (1) to (3), wherein the polymer having unsaturated bonds is at least one selected from styrene-butadiene rubber, nitrile rubber and butadiene rubber.

[0014] (5) The present invention provides a current collector of any one of (1) to (4), wherein the vulcanizing agent includes a sulfur donor and a vulcanization accelerator.

[0015] (6) The present invention provides a current collector of any one of (1) to (5), wherein the weight ratio of sulfur donor to sulfurization accelerator is in the range of 1:1 to 1:5.

[0016] (7) The present invention provides a current collector of any one of (1) to (6), wherein the weight ratio of the polymer having unsaturated bonds to the vulcanizing agent is in the range of 5:1 to 10:1.

[0017] (8) The present invention provides a current collector of any one of (1) to (7), wherein the weight ratio of the conductive material to the three-dimensional mesh structure adhesive is in the range of 1:1 to 1:4.

[0018] (9) The present invention provides a current collector of any one of (1) to (8), wherein the thickness of the primer layer is about 0.1 μm or greater and about 20 μm or less.

[0019] (10) The present invention provides a current collector of any one of (1) to (9), wherein the substrate comprises at least one metal selected from Al, Ti, Ni, Cu and SUS.

[0020] (11) The present invention provides a current collector of any one of (1) to (10), wherein the thickness of the substrate is about 3 μm or more and about 30 μm or less.

[0021] (12) The present invention provides a current collector of any one of (1) to (11), wherein the substrate is in the form of foil, mesh or foam.

[0022] (13) The present invention provides an electrode for an all-solid-state battery, comprising: a current collector according to any one of (1) to (12); and an electrode layer disposed on the current collector, wherein the electrode layer comprises an electrode active material and a solid electrolyte.

[0023] (14) The present invention provides a method for manufacturing an electrode for an all-solid-state battery, the method comprising the following steps: (S1) preparing a primer slurry comprising a conductive material, a polymer having unsaturated bonds and a sulfiding agent; (S2) coating the primer slurry onto a substrate to have a predetermined thickness and drying the primer slurry to form a primer layer on the substrate; (S3) further coating the primer layer with an electrode slurry comprising an electrode active material and a solid electrolyte and drying it to form an electrode layer on the primer layer; and (S4) drying the primer layer at a temperature of 120°C or higher and 180°C or lower to crosslink the polymer having unsaturated bonds with the sulfiding agent.

[0024] (15) The present invention provides a method for manufacturing an electrode for an all-solid-state battery according to (14), wherein the weight ratio of electrode active material to solid electrolyte in the electrode slurry is in the range of 3:1 to 5:1.

[0025] (16) The present invention provides (14) or (15) a method for manufacturing an electrode for an all-solid-state battery, wherein, based on 100 parts by weight of the combination of all materials contained in the electrode slurry, the content of the binder is 1 to 3 parts by weight, the content of the dispersant is 0 to 1 part by weight, and the content of the conductive material is 1 to 2 parts by weight.

[0026] (17) The present invention provides a method for manufacturing an electrode for an all-solid-state battery according to any one of (14) to (16), wherein the primer slurry and the electrode slurry each contain an organic solvent, wherein the organic solvent is at least one selected from butyl butyrate, hexyl butyrate, benzyl acetate, o-xylene, toluene, dibromomethane and anisole.

[0027] (18) The present invention provides a method for manufacturing an electrode for an all-solid-state battery according to any one of (14) to (17), wherein the drying in (S2) is performed at about 90°C to about 120°C for 60 minutes or less.

[0028] (19) The present invention provides a method for manufacturing an electrode for an all-solid-state battery according to any one of (14) to (18), wherein the drying in (S3) is performed at about 90°C to about 120°C for 60 minutes or less.

[0029] (20) The present invention provides an all-solid-state battery comprising (13) electrodes for an all-solid-state battery. Detailed Implementation

[0030] The invention will be described in more detail below.

[0031] The terms or words used in this specification and claims should not be construed as limited to their ordinary or dictionary meanings, but rather as meanings and concepts consistent with the technical spirit of the invention, based on the principle that the inventors can appropriately define the concepts of the terms in order to best interpret their invention. The terms “substantially,” “about,” and “approximately” used herein may provide industry-accepted tolerances for the relationships between their respective terms and / or items, such as tolerances of ±1%, ±5%, or ±10% of the actual values, and other suitable tolerances.

[0032] current collector

[0033] The present invention provides a current collector comprising a substrate and a primer layer disposed on the substrate, wherein the primer layer comprises a conductive material and an adhesive having a three-dimensional network structure, and the adhesive having a three-dimensional network structure comprises crosslinking between a polymer having unsaturated bonds and a vulcanizing agent.

[0034] The current collector of this invention allows the primer layer disposed on the substrate to contact the electrode layer, thereby maximizing the contact between the electrode layer and the current collector and achieving low interfacial resistance. Furthermore, the binder included in the primer layer has a three-dimensional network structure, which minimizes particle movement within the primer layer during charging and discharging, thereby improving adhesion between the primer layer and the electrode layer. Additionally, the primer layer may contain conductive materials to provide excellent conductivity, thereby improving electrode lifetime characteristics while maximizing the adhesion improvement effect.

[0035] primer layer

[0036] The primer layer included in the current collector of the present invention is characterized in that the primer layer comprises a conductive material and an adhesive having a three-dimensional network structure.

[0037] Conductive materials are used to ensure the conductivity of the primer layer, and in particular, they can be spherical conductive materials. Spherical conductive materials can include one or more selected from carbon black, acetylene black, ketjen black, and furnace black.

[0038] Furthermore, the BET specific surface area of ​​conductive materials can be approximately 50 m². 2 / g or greater and approximately 100m 2 / g or less, preferably about 55m 2 / g or larger, approximately 60m 2 / g or larger, or approximately 65m 2 / g or greater, and approximately 95m 2 / g or less, approximately 90m 2 / g or less, approximately 85m 2 / g or less, or about 80m 2 / g or less.

[0039] When using the aforementioned spherical conductive material with low BET specific surface area, the adhesive is mainly distributed on the upper part of the primer layer, and the adhesive distributed on the upper part of the primer layer can bond more firmly with the electrode layer, thereby improving the adhesion between the current collector and the electrode layer.

[0040] Three-dimensional network adhesives can contain crosslinks between polymers with unsaturated bonds and vulcanizing agents.

[0041] The polymer containing unsaturated bonds can be a butadiene rubber-like polymer, more specifically, it can be one or more selected from styrene-butadiene rubber, nitrile rubber, and butadiene rubber. The three-dimensional network structure can be formed by reacting the double bonds contained in the polymer with a vulcanizing agent, as will be described below. The three-dimensional network structure minimizes particle movement in the primer layer, preventing conductive materials from migrating to the top of the primer layer during charging / discharging, thereby maintaining excellent adhesion.

[0042] In one example, the vulcanizing agent may comprise a sulfur donor and a vulcanization accelerator. The sulfur donor is a component that directly forms crosslinks with a polymer having unsaturated bonds. Different polymer chains crosslink with each other through the sulfur donor, thereby forming a three-dimensional network structure. The sulfur donor can be elemental sulfur or an organic sulfur donor; the organic sulfur donor can be one or more selected from tetramethylthiuram disulfide (TMTD), 4,4'-dithiodimorpholine (DTDM), tetrasulfide bis(pentamethylenethiuram) tetrasulfide (DPTT), and thiocarbamyl sulfenamide (OTOS).

[0043] A vulcanization accelerator is a component used to further promote the crosslinking between unsaturated bonds in a polymer with unsaturated bonds and sulfur donors. The vulcanization accelerator may be one or more selected from thiazole vulcanization accelerators, aldehyde-amine vulcanization accelerators, guanidine vulcanization accelerators, thiophosphate vulcanization accelerators, sulfenamide vulcanization accelerators, thiourea vulcanization accelerators, thiuram vulcanization accelerators, dithiocarbamate vulcanization accelerators, and xanthate vulcanization accelerators, preferably thiazole vulcanization accelerators.

[0044] The thiazole-based vulcanization accelerator may be one or more selected from 2-mercaptobenzothiazole (MBT), 2,2'-dithiobis(benzothiazole) (MBTS) and zinc-2-mercaptobenzothiazole (ZMBT), with 2-mercaptobenzothiazole being preferred.

[0045] Aldehyde-amine accelerators can be heptanal-aniline condensate (BA), and guanidine accelerators can be diphenylguanidine (DPG), N,N'-di-o-tolylguanidine (DOTG), or mixtures thereof.

[0046] Thiophosphate-based sulfidation accelerators can be zinc O,O-di-N-dithiophosphate (ZBDP), and sulfenamide-based sulfidation accelerators can be one or more selected from N-cyclohexyl-2-benzothiazole sulfenamide (CBS), N-tert-butyl-2-benzothiazole sulfenamide (TBBS), 2-(4-morpholinylthio)benzothiazole (MBS), and N,N'-dicyclohexyl-2-benzothiazole sulfenamide (DCBS).

[0047] Thiourea vulcanization accelerators can be one or more selected from ethyl thiourea (ETU), di-pentamethylene thiourea (DPTU), and dibutyl thiourea (DBTU).

[0048] Thiuram-based vulcanization accelerators may be one or more selected from tetramethylthiuram monosulfide (TMTM), tetramethylthiuram disulfide (TMTD), bis(pentamethylenethiuram) tetrasulfide (DPTT), and tetrabenzylthiuram disulfide (TBzTD).

[0049] Dithiocarbamate vulcanization accelerators can be one or more selected from zinc dimethyl dithiocarbamate (ZDMC), zinc diethyl dithiocarbamate (ZDEC), zinc dibutyl dithiocarbamate (ZDBC), and zinc dibenzyl dithiocarbamate (ZDBC).

[0050] Xanthate sulfidation accelerators can be zinc isopropyl xanthate (ZIX).

[0051] The weight ratio of sulfur donor to vulcanization accelerator in the vulcanizing agent can be in the range of 1:1 to 1:5, preferably 1:1 to 1:4. When the content of vulcanization accelerator is too low, the improvement effect of the vulcanization accelerator may not be obvious. When the content of vulcanization accelerator is too high, the content of sulfur donor may be relatively low, and therefore sufficient crosslinking may not be achieved.

[0052] The weight ratio of the polymer with unsaturated bonds to the vulcanizing agent can range from 5:1 to 10:1, preferably from 6:1 to 9:1. When the polymer content is too high, the areas that are not cross-linked by the vulcanizing agent increase, thus failing to form a sufficient three-dimensional network structure. When the polymer content is too low, the vulcanizing agent may be excessive, forming more cross-links than necessary, which may cause the adhesive itself to harden, thus failing to fully exert the original function of the adhesive.

[0053] The weight ratio of the conductive material to the adhesive with a three-dimensional network structure can be in the range of 1:1 to 1:4, preferably 1:1.5 to 1:3.5. When the content of the conductive material is too low, its effect may be negligible. When the content of the conductive material is too high, the excess conductive material may be located on top of the primer layer, thereby weakening the adhesion between the primer layer and the electrode layer. In this regard, the weight of the adhesive with a three-dimensional network structure can refer to the combined weight of the polymer with unsaturated bonds and the vulcanizing agent.

[0054] The thickness of the primer layer can be about 0.1 μm or greater and about 20 μm or less, preferably 0.5 μm or greater and 15 μm or less. When the thickness of the primer layer is too small, the function of the primer layer itself may not be fully realized. When the thickness of the primer layer is too large, the distance between the substrate and the electrode layer increases, which may be undesirable in terms of electrode performance.

[0055] The substrate supports the primer layer and can be a conventional current collector. More specifically, the substrate may contain one or more metals selected from Al, Ti, Ni, Cu, and SUS. These metals offer advantages in terms of excellent electrical conductivity, excellent mechanical properties, and durability.

[0056] The substrate thickness can be 3 μm or greater and 30 μm or less, preferably 4 μm or greater and 25 μm or less. When the substrate thickness is too small, the mechanical strength of the current collector may not meet the minimum requirements. When its thickness is too large, the economic viability of the current collector may deteriorate.

[0057] The substrate can be in the form of foil, mesh, or foam. The substrate can be shaped in this way to maximize its contact area with the primer layer.

[0058] Electrodes for all-solid-state batteries

[0059] The present invention provides an electrode for an all-solid-state battery comprising the above-described current collector.

[0060] More specifically, the present invention provides an electrode for an all-solid-state battery, comprising a current collector and an electrode layer disposed on the current collector, wherein the electrode layer comprises an electrode active material and a solid electrolyte.

[0061] Depending on the type of electrode active material contained in the electrode layer, the electrode can be either a positive or negative electrode.

[0062] When the electrode is a positive electrode, the electrode layer can contain a positive electrode active material and a solid electrolyte. Known lithium-based positive electrode active materials can be used. Furthermore, the solid electrolyte can be any known sulfide-based solid electrolyte, chloride-based solid electrolyte, oxide-based solid electrolyte, etc., without particular limitations.

[0063] When the electrode is a negative electrode, the electrode layer can contain a negative electrode active material and a solid electrolyte. Known carbon-based or silicon-based negative electrode active materials can be used. The solid electrolyte can be any type described above, without particular restriction.

[0064] The electrode can be either positive or negative, with positive being preferred.

[0065] Methods for manufacturing electrodes for all-solid-state batteries

[0066] This invention provides a method for manufacturing electrodes for all-solid-state batteries.

[0067] More specifically, the present invention provides a method for manufacturing an electrode for an all-solid-state battery, comprising the following steps: (S1) preparing a primer slurry comprising a conductive material, a polymer having unsaturated bonds, and a sulfiding agent; (S2) coating the primer slurry onto a substrate to a predetermined thickness, and drying the primer slurry to form a primer layer on the substrate; (S3) further coating the primer layer with an electrode slurry comprising an electrode active material and a solid electrolyte and drying it to form an electrode layer on the primer layer; and (S4) drying the primer layer at a temperature of 120°C or higher and 180°C or lower to crosslink the polymer having unsaturated bonds with the sulfiding agent.

[0068] In the method for manufacturing electrodes for all-solid-state batteries according to the present invention, the conductive material, the polymer having unsaturated bonds, and the sulfiding agent can be the same as described above. Furthermore, the electrode active material and the solid electrolyte can also be the same as described above.

[0069] The solvent for the primer slurry prepared in step S1 can be an organic solvent. The organic solvent has a boiling point and vapor pressure that can be completely removed under the heat treatment conditions of sulfidation temperature and time. Furthermore, it is preferable to use a component with low reactivity with the solid electrolyte as the solvent.

[0070] Specific examples of organic solvents may be one or more selected from butyl butyrate, hexyl butyrate, benzyl acetate, o-xylene, toluene, dibromomethane, and anisole. Preferably, the organic solvent may be butyl butyrate, hexyl butyrate, or a mixture thereof, more preferably butyl butyrate.

[0071] Depending on the volatility of the organic solvent, the specific temperature and time for drying can vary. In one example, drying in step S2 can be carried out at about 90°C to about 120°C for 60 minutes or less, preferably 30 minutes or less. Drying in this step can be carried out under conditions where only the solvent is removed without a crosslinking reaction occurring.

[0072] The solvent used in step S3 for the electrode slurry containing the electrode active material and solid electrolyte can be the aforementioned organic solvent. In addition to the electrode active material and solid electrolyte, the electrode slurry may also contain a binder, a dispersant, and a conductive material. The conductive material may be the same as the conductive material described above, or a different conductive material. Commonly used conductive materials can be used. The binder may also be the binder described above, or a commonly used binder. The weight ratio of the electrode active material to the solid electrolyte in the electrode slurry can be in the range of 3:1 to 5:1. Based on all the material combinations contained in 100 parts by weight of the electrode slurry, the binder content can be 1 to 3 parts by weight, the dispersant content can be 0 to 1 part by weight, and the conductive material content can be 1 to 2 parts by weight. In one example, all the materials contained in the electrode slurry can be the electrode active material, solid electrolyte, conductive material, dispersant, and binder.

[0073] Similar to the drying in step S2, the drying in step S3 can also be carried out at about 90°C to about 120°C for 60 minutes or less, preferably 30 minutes or less. This drying step can be carried out under conditions where only the solvent is removed without a crosslinking reaction occurring.

[0074] After forming a primer layer on the substrate and an electrode layer on the primer layer through the above process, crosslinking is finally induced through step S4, resulting in a three-dimensional network structure in the binder of the primer layer. Step S4 can be a drying step performed at a temperature of 120°C or higher and 180°C or lower to allow crosslinking between the polymer with unsaturated bonds and the vulcanizing agent, and the drying can be carried out for 4 to 10 hours. In this step, crosslinking can occur between the vulcanizing agent and the polymer with unsaturated bonds.

[0075] All-solid-state batteries

[0076] The present invention provides an all-solid-state battery comprising the electrodes described above for all-solid-state batteries.

[0077] When the electrode used in an all-solid-state battery is the positive electrode, the all-solid-state battery may also include a negative electrode and a solid electrolyte layer disposed between the positive and negative electrodes.

[0078] When the electrode used in an all-solid-state battery is the negative electrode, the all-solid-state battery may also include a positive electrode and a solid electrolyte layer disposed between the negative electrode and the positive electrode.

[0079] The invention will be described in more detail below with reference to embodiments. However, the following embodiments are for illustrative purposes only, and the scope of the invention is not limited to these embodiments.

[0080] Material

[0081] Butadiene rubber (BR) was used as a polymer with unsaturated bonds. A vulcanizing agent was obtained by mixing organic sulfur with 2-mercaptobenzothiazole (MBT) as a vulcanization accelerator in a 1:1 weight ratio. As a conductive material, BET with a specific surface area of ​​70 m² was used. 2 The specific surface area of ​​carbon black and BET is 200 m² / g. 2 / g of carbon nanotubes.

[0082] A foil-shaped Al substrate is used as the substrate.

[0083] Examples and Comparative Examples

[0084] The polymer, vulcanizing agent, and conductive material from the above materials were mixed in the weight ratios listed in Table 1 below, and the mixture was added to hexyl butyrate as an organic solvent to prepare a slurry for forming a primer layer. The slurry was coated onto a substrate of the material to a thickness of approximately 0.7 μm and dried at approximately 90°C for 15 minutes.

[0085] Then, a slurry containing NCM-type positive electrode active material, azyrodite-type solid electrolyte, and the same adhesive used in the primer layer is applied to the previously formed primer layer, and then dried at about 90°C for 15 minutes.

[0086] After the primer layer and positive electrode layer are finally formed, they are placed in a vacuum chamber and dried at 140°C for 4 hours to prepare the positive electrode of the all-solid-state battery. The positive electrode slurry used in Example 3 contains the same components as those used in Example 1, except for the content of the binder.

[0087] Table 1

[0088]

[0089] Experimental Example 1: Measurement of DC-IR and lifetime characteristics of an all-solid-state battery including a positive electrode for an all-solid-state battery.

[0090] The DC-IR and lifetime characteristics of all-solid-state batteries containing the positive electrodes prepared in the examples and comparative examples were measured. Specifically, all-solid-state batteries were prepared under the same conditions, except that the positive electrodes prepared in the examples and comparative examples were used. Each all-solid-state battery underwent a first cycle of constant current (CC) charge-discharge at a voltage of 2.0 to 4.25 V, a current of 0.2 C (8.8 mA), and a temperature of 30 °C. Then, in the second cycle, CC charging was performed at 4.25 V, followed by CC discharging until 50% of the first cycle discharge capacity was reached, and then CC discharging was performed for 10 seconds at a current of 0.33 C (14.7 mA). At this time, the DC-IR value (ΔV / I) was obtained by the ratio of the voltage drop during the 10-second discharge to the applied current. Then, starting from the third cycle, charge-discharge was performed at a rate of 0.2 C (8.8 mA), and the capacity retention rate relative to the third cycle capacity was measured to evaluate durability. The results are shown in Table 2.

[0091] Table 2

[0092] DC-IR[Ω] Lifespan (60 cycles) Example 1 16.2 87.0％ Example 2 18.4 76.9％ Example 3 15.5 91.0％ Comparative example 17.8 84.4％

[0093] As shown in Table 2, the all-solid-state battery using the positive electrode of the present invention exhibits low resistance and excellent lifetime characteristics, especially when using spherical conductive materials, this improvement is particularly significant.

[0094] Experimental Example 2: Determination of the adhesion strength of the positive electrode layer

[0095] In the all-solid-state battery cathodes prepared in the Examples and Comparative Examples, the adhesion strength between the primer layer and the cathode layer was determined. More specifically, the tensile strength of the prepared cathode samples was measured by peeling in the horizontal direction (180 degrees) at a rate of 30 mm / min using a universal testing machine (UTM). The adhesion values ​​of Examples 1 to 3 are expressed as relative values, with the adhesion value of 1 in the Comparative Examples as a baseline.

[0096] Furthermore, it was determined whether the foil serving as the substrate was exposed due to detachment during the die-cutting process of the positive electrodes prepared in the examples and comparative examples. The results of measuring adhesion force and checking for foil exposure are summarized in Table 3.

[0097] Table 3

[0098] Adhesion force (relative value) The foil was exposed due to detachment during the mold grooving process. Example 1 2.40 X Example 2 1.15 X Example 3 1.80 X Comparative example 1.00 O

[0099] As can be seen from Table 3 above, in the examples where a primer layer containing an adhesive with a three-dimensional mesh structure was applied, the adhesion between the electrode layer and the substrate was high. However, in the comparative examples using only conventional adhesives, low adhesion was observed, and the electrode layer was prone to detachment during the mold grooving process, easily exposing the substrate.

[0100] This fact demonstrates that when using the current collector of the present invention, the adhesion between the electrode layer and the current collector can be maintained at an excellent level, and the performance of the electrode itself can also be maintained at an excellent level.

[0101] The current collector of the present invention contacts the electrode layer through a primer layer disposed on the substrate. The primer layer can make better contact with the electrode layer, thereby reducing the interface resistance and improving the electrode performance.

[0102] In addition, the primer layer contains an adhesive with a three-dimensional network structure, which inhibits the movement of particles in the primer layer during charging and discharging, thereby improving the adhesion between the current collector and the electrode layer.

[0103] Furthermore, since the primer layer contains a highly dispersible conductive material, a relatively large amount of adhesive can be distributed in the upper region of the primer layer, thereby maximizing the improvement in adhesion and improving the lifespan characteristics of the electrode.

[0104] While the present invention has been described above with reference to exemplary embodiments, it is not limited thereto. Various modifications and variations can be made to the present invention by those skilled in the art without departing from the spirit and scope of the invention as claimed in the claims.

Claims

1. A current collector, comprising: substrate; as well as A primer layer disposed on the substrate The primer layer comprises a conductive material and an adhesive having a three-dimensional network structure. The adhesive having a three-dimensional network structure comprises crosslinking between a polymer with unsaturated bonds and a vulcanizing agent.

2. The current collector according to claim 1, wherein the conductive material is a spherical conductive material.

3. The current collector according to claim 1, wherein the BET specific surface area of ​​the conductive material is 50 m². 2 / g or greater and 100m 2 / g or less.

4. The current collector according to claim 1, wherein the polymer having unsaturated bonds is at least one selected from styrene-butadiene rubber, nitrile rubber and butadiene rubber.

5. The current collector according to claim 1, wherein the vulcanizing agent comprises a sulfur donor and a vulcanization accelerator.

6. The current collector according to claim 5, wherein the weight ratio of the sulfur donor to the vulcanization accelerator is in the range of 1:1 to 1:

5.

7. The current collector according to claim 1, wherein the weight ratio of the polymer having unsaturated bonds to the vulcanizing agent is in the range of 5:1 to 10:

1.

8. The current collector according to claim 1, wherein the weight ratio of the conductive material to the adhesive having a three-dimensional network structure is in the range of 1:1 to 1:

4.

9. The current collector according to claim 1, wherein the thickness of the primer layer is 0.1 μm or greater and 20 μm or less.

10. The current collector according to claim 1, wherein the substrate comprises at least one metal selected from Al, Ti, Ni, Cu and SUS.

11. The current collector according to claim 1, wherein the thickness of the substrate is 3 μm or greater and 30 μm or less.

12. The current collector according to claim 1, wherein the substrate is in the form of foil, mesh or foam.

13. An electrode for an all-solid-state battery, comprising: The current collector according to any one of claims 1-12; as well as Electrode layer disposed on the current collector The electrode layer contains an electrode active material and a solid electrolyte.

14. A method for manufacturing an electrode for an all-solid-state battery, the method comprising the steps of: Step S1: Prepare a primer slurry containing conductive materials, a polymer with unsaturated bonds, and a vulcanizing agent; Step S2: Apply the primer slurry to the substrate to a predetermined thickness, and dry the primer slurry to form a primer layer on the substrate; Step S3: Further, an electrode slurry containing electrode active material and solid electrolyte is coated onto the primer layer and dried to form an electrode layer on the primer layer; and Step S4: Dry the primer layer at a temperature of 120°C or higher and 180°C or lower to allow crosslinking between the polymer with unsaturated bonds and the vulcanizing agent.

15. The method of manufacturing an electrode for an all-solid-state battery according to claim 14, wherein the weight ratio of the electrode active material to the solid electrolyte in the electrode slurry is in the range of 3:1 to 5:

1.

16. The method of manufacturing an electrode for an all-solid-state battery according to claim 14, wherein, in addition to the electrode active material and the solid electrolyte, the electrode slurry further comprises a binder, a dispersant, and a conductive material, and the binder comprises 1 to 3 parts by weight, the dispersant comprises 0 to 1 part by weight, and the conductive material comprises 1 to 2 parts by weight, based on 100 parts by weight of the combination of all materials contained in the electrode slurry.

17. The method of manufacturing an electrode for an all-solid-state battery according to claim 14, wherein the primer slurry and the electrode slurry each comprise an organic solvent. The organic solvent is selected from at least one of butyl butyrate, hexyl butyrate, benzyl acetate, o-xylene, toluene, dibromomethane, and anisole.

18. The method of manufacturing an electrode for an all-solid-state battery according to claim 14, wherein the drying in step S2 is performed at 90°C to 120°C for 60 minutes or less.

19. The method of manufacturing an electrode for an all-solid-state battery according to claim 14, wherein the drying in step S3 is performed at 90°C to 120°C for 60 minutes or less.

20. An all-solid-state battery comprising the electrodes for an all-solid-state battery according to claim 13.

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