All-solid-state battery and method for manufacturing the same

Abstract

To provide an all-solid battery and a manufacturing method thereof that can apply a negative electrode buffer layer and a positive electrode buffer layer to minimize the electrode void ratio that may occur after a rolling process and maximize the interfacial adhesion area between layers.SOLUTION: An all-solid battery according to an embodiment of the present invention includes: a sulfide-based solid electrolyte layer; a negative electrode including a negative electrode active material layer laminated on one surface of the solid electrolyte layer, and a negative electrode buffer layer laminated on one surface of the negative electrode active material layer; and a positive electrode including a positive electrode active material layer laminated on the other surface of the solid electrolyte layer, and a positive electrode buffer layer laminated on the other surface of the positive electrode active material layer.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an all-solid-state battery and a manufacturing method thereof, and more particularly to an all-solid-state battery capable of reducing porosity and a manufacturing method thereof. [Background technology]

[0002] Generally, lithium-ion batteries that use liquid electrolytes have a structure in which a separator separates the negative and positive electrodes. If the separator is broken due to deformation or external impact, a short circuit can occur, which can lead to risks such as overheating or explosion.

[0003] Therefore, the development of a solid electrolyte that can ensure safety in the field of secondary batteries is a very important issue.

[0004] The all-solid-state battery using the solid electrolyte has the advantages of increasing the safety of the battery, preventing leakage of the electrolyte, improving the reliability of the battery, and facilitating the manufacture of a thin battery.

[0005] In addition, lithium metal can be used as the negative electrode, which can improve the energy density. As a result, it is expected to be applied to small secondary batteries as well as high-capacity secondary batteries for electric vehicles, and is attracting attention as a next-generation battery.

[0006] In the conventional technology, the all-solid-state battery is manufactured by laminating multiple layers and then bonding them through a rolling process.

[0007] For example, in all-solid-state batteries according to conventional technology, negative and positive electrodes are stacked symmetrically with a solid electrolyte sandwiched between them.

[0008] In this case, the negative electrode and the positive electrode each include a hard current collector and a soft active material layer.

[0009] Although the porosity of the interior of such an all-solid-state battery can be reduced by the rolling process, there is a problem in that voids are reformed due to the springback phenomenon of the material or the volume change of the active material during charging and discharging.

[0010] In other words, the upper part of each electrode can minimize the change in porosity by acting as a buffer during charging and discharging due to the soft solid electrolyte layer, but the lower part of each electrode is an adhesive between the hard current collector and the material, so the porosity may increase due to the volume change at the interface between each material.

[0011] As a result, all-solid-state batteries according to conventional technologies have the problem that the ionic conductivity and electronic conductivity may decrease due to the increased porosity, which may adversely affect the battery performance in the long term.

[0012] The matters described in this background art section are prepared to enhance understanding of the background of the invention, and may include matters that are not prior art already known to those having ordinary skill in the art to which this technology pertains. Summary of the Invention [Problem to be solved by the invention]

[0013] An embodiment of the present invention provides an all-solid-state battery and a manufacturing method thereof that can minimize electrode porosity that may occur after a rolling process by applying an anode buffer layer and a cathode buffer layer and maximize the interfacial adhesion area between each layer. [Means for solving the problem]

[0014] In one or more embodiments of the present invention, an all-solid-state battery may be provided, including: an anode electrode including a sulfide-based solid electrolyte layer; an anode active material layer stacked on one surface of the solid electrolyte layer; and an anode buffer layer stacked on one surface of the anode active material layer; and a cathode electrode including a cathode active material layer stacked on the other surface of the solid electrolyte layer; and a cathode buffer layer stacked on the other surface of the cathode active material layer.

[0015] The negative electrode may include a negative electrode current collector layer having a surface roughness formed on one side thereof, a negative electrode primer layer disposed on one side of the negative electrode current collector layer and made of a mixture of a carbon-based conductive material and a binder, a negative electrode buffer layer disposed on one side of the negative electrode primer layer and made of a mixture of a sulfide-based material, a conductive material, and a binder, and a negative electrode active material layer disposed on one side of the negative electrode buffer layer and made of a mixture of a sulfide-based material, a negative electrode active material, a conductive material, and a binder, and in contact with the solid electrolyte layer.

[0016] The negative electrode current collector may include at least one material selected from the group consisting of copper, stainless steel, titanium, iron, and nickel.

[0017] The negative electrode primer layer may be formed by mixing a carbonaceous conductive material and a binder in a ratio of 7:3 to 9.5:0.5.

[0018] In addition, the negative electrode buffer layer may be composed of a mixture of a sulfide-based material in a range of 60 wt% to 90 wt% based on the total weight of the negative electrode, a conductive material in a range of 9 wt% to 30 wt% based on the total weight of the negative electrode, and a binder in a range of 1 wt% to 10 wt% based on the total weight of the negative electrode.

[0019] The negative electrode buffer layer may be characterized by being softer than the negative electrode primer layer.

[0020] In addition, the negative electrode buffer layer may have the same ionic conductivity and electronic conductivity as the negative electrode active material layer.

[0021] In addition, the negative electrode active material layer may be composed of a mixture of 8 wt% to 30 wt% of a sulfide-based material, 60 wt% to 90 wt% of a negative electrode active material, 1 wt% to 10 wt% of a conductive material, and 1 wt% to 10 wt% of a binder, based on a total weight of 100.

[0022] The positive electrode may include a positive electrode current collector having a surface roughness formed on one side thereof; a positive electrode primer layer disposed on one side of the positive electrode current collector and made of a mixture of a carbon-based conductive material and a binder; a positive electrode buffer layer disposed on one side of the positive electrode primer layer and made of a mixture of a sulfide-based material, a conductive material, and a binder; and a positive electrode active material layer disposed on one side of the positive electrode buffer layer and made of a mixture of a sulfide-based material, a negative electrode active material, a conductive material, and a binder, in contact with the solid electrolyte layer.

[0023] The positive electrode current collector may include at least one material selected from the group consisting of stainless steel, titanium, iron, nickel, aluminum, and chromium.

[0024] The positive electrode primer layer may be formed by mixing a carbonaceous conductive material and a binder in a ratio of 7:3 to 9.5:0.5.

[0025] In addition, the positive electrode buffer layer may be composed of a mixture of a sulfide-based material in a range of 60 wt% to 90 wt% based on a total weight of 100, a conductive material in a range of 9 wt% to 30 wt%, and a binder in a range of 1 wt% to 10 wt% based on a total weight of 100.

[0026] The positive electrode buffer layer may be characterized by being softer than the positive electrode primer layer.

[0027] In addition, the positive electrode buffer layer may have the same ionic conductivity and electronic conductivity as the positive electrode active material layer.

[0028] In addition, the positive electrode active material layer may be composed of a mixture of 8 wt% to 30 wt% of a sulfide-based material, 60 wt% to 90 wt% of a positive electrode active material, 1 wt% to 10 wt% of a conductive material, and 1 wt% to 10 wt% of a binder, based on a total weight of 100. [Effects of the Invention]

[0029] The all-solid-state battery and manufacturing method thereof according to an embodiment of the present invention may have an effect of minimizing electrode porosity that may occur after a rolling process and maximizing the interfacial adhesion area between each layer by applying an anode buffer layer and a cathode buffer layer.

[0030] In addition, the all-solid-state battery and the manufacturing method thereof according to the embodiment of the present invention can minimize deformation due to volume change of the anode active material or the cathode active material that may occur during charging and discharging, thereby improving the life characteristics.

[0031] Other effects that can be obtained or are expected to be obtained by the embodiments of the present invention will be directly or implicitly disclosed in the detailed description of the embodiments of the present invention, i.e., various effects expected by the embodiments of the present invention will be disclosed in the detailed description to be given later. [Brief explanation of the drawings]

[0032] [Figure 1] FIG. 1 is a diagram illustrating a cross-sectional structure of an all-solid-state battery according to an embodiment of the present invention. [Figure 2] FIG. 1 is a diagram illustrating a cross-sectional structure of a negative electrode of an all-solid-state battery according to an embodiment of the present invention. [Figure 3] FIG. 1 is a diagram illustrating a cross-sectional structure of a positive electrode of an all-solid-state battery according to an embodiment of the present invention. [Figure 4] 1A to 1C are diagrams sequentially illustrating a method for manufacturing an all-solid-state battery according to an embodiment of the present invention. [Figure 5] 1A to 1C are diagrams sequentially illustrating a method for manufacturing an all-solid-state battery according to an embodiment of the present invention. [Figure 6] 1A to 1C are diagrams sequentially illustrating a method for manufacturing an all-solid-state battery according to an embodiment of the present invention. [Figure 7] 1A to 1C are diagrams sequentially illustrating a method for manufacturing an all-solid-state battery according to an embodiment of the present invention. [Figure 8] 1A to 1C are diagrams sequentially illustrating a method for manufacturing an all-solid-state battery according to an embodiment of the present invention. [Figure 9]1A to 1C are diagrams sequentially illustrating a method for manufacturing an all-solid-state battery according to an embodiment of the present invention. [Figure 10] 1A to 1C are diagrams sequentially illustrating a method for manufacturing an all-solid-state battery according to an embodiment of the present invention. [Figure 11] 1A to 1C are diagrams sequentially illustrating a method for manufacturing an all-solid-state battery according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0033] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described in detail with reference to the accompanying drawings, so that those skilled in the art can easily practice the present invention. However, as those skilled in the art may realize, the present invention is not limited to the embodiments set forth herein.

[0034] In order to clearly explain the present invention, parts that are not necessary for the explanation will be omitted, and the same or similar components will be described by using the same reference numerals throughout the specification.

[0035] FIG. 1 is a diagram illustrating a schematic cross-sectional structure of an all-solid-state battery according to an embodiment of the present invention, FIG. 2 is a diagram illustrating a schematic cross-sectional structure of a negative electrode of the all-solid-state battery according to an embodiment of the present invention, and FIG. 3 is a diagram illustrating a schematic cross-sectional structure of a positive electrode of the all-solid-state battery according to an embodiment of the present invention.

[0036] Referring to FIG. 1, an all-solid-state battery 1 according to an embodiment of the present invention includes a sulfide-based solid electrolyte layer 10, an anode electrode 20, and a cathode electrode 30.

[0037] A negative electrode 20 is laminated on one surface of the solid electrolyte layer 10, and a positive electrode 30 is laminated on the other surface.

[0038] For example, the negative electrode 20 can be stacked below the solid electrolyte layer 10, and the positive electrode 30 can be stacked above it.

[0039] In the embodiment of the present invention, left and right, front and rear, and up and down directions are set based on the drawing, and upward portions are defined as the upper portion, upper end, upper surface, and upper end portion, and downward portions are defined as the lower portion, lower end, lower surface, and lower end portion.

[0040] The definition of the reference direction as described above has a relative meaning, and the direction may change depending on the reference position of the all-solid-state battery 1 of the present invention, and therefore the reference direction is not necessarily limited to the reference direction of this embodiment.

[0041] In an embodiment of the present invention, the solid electrolyte layer 10 may be made of a sulfide-based material including a lithium sulfide-based compound or an argyrodite-based compound.

[0042] This is because the sulfide-based material used in the solid electrolyte layer 10 has a softer characteristic than the oxide-based material, and is therefore advantageously suited to the structural characteristics of the all-solid-state battery 1 according to the embodiment of the present invention.

[0043] Such a solid electrolyte layer 10 has an ionic conductivity of 1*10 -3 It is advantageous to apply materials with a strength of S / cm or higher.

[0044] The particle size (average diameter of each particle constituting the powder) of the solid electrolyte layer 10 can be set in the range of 0.1 μm to 10 μm.

[0045] Such a solid electrolyte layer 10 has a density of 0.1 g / cm 3 More than 1g / cm 3 It can be formed with a density set within the following range.

[0046] The solid electrolyte layer 10 can be formed to a thickness of 50 μm or more and 100 μm or less.

[0047] Referring to FIG. 2, in this embodiment of the present invention, the negative electrode 20 includes a negative electrode current collector 21, a negative electrode primer layer 23, a negative electrode buffer layer 25, and a negative electrode active material layer 27.

[0048] The negative electrode current collector 21 may be formed of at least one material selected from the group consisting of copper, stainless steel, titanium, iron, and nickel.

[0049] Such a negative electrode current collector 21 has surface roughness on its upper surface.

[0050] The surface roughness means the degree of minute irregularities occurring on the surface.

[0051] Such surface roughness can be formed through plasma or corona surface treatment.

[0052] The negative electrode current collector 21 can be formed to a thickness of 15 μm or more and 20 μm or less.

[0053] A negative electrode primer layer 23 is formed on the upper surface of the negative electrode current collector 21 .

[0054] The negative electrode primer layer 23 may be made of a mixture of a carbon-based conductive material and a binder.

[0055] For example, the negative electrode primer layer 23 may be formed by mixing a conductive material and a binder in a ratio of 7:3 to 9.5:0.5.

[0056] The negative electrode primer layer 23 can be formed to a thickness of 1 μm or less.

[0057] A negative electrode buffer layer 25 is formed on the upper surface of the negative electrode primer layer 23 .

[0058] The negative electrode buffer layer 25 can be formed by mixing a sulfide-based material, a conductive material, and a binder.

[0059] For example, the negative electrode buffer layer 25 may be composed of a mixture of a sulfide-based material in a range of 60 wt% to 90 wt% based on the total weight of the negative electrode, a conductive material in a range of 9 wt% to 30 wt% based on the total weight of the negative electrode, and a binder in a range of 1 wt% to 10 wt% based on the total weight of the negative electrode.

[0060] The negative electrode buffer layer 25 may have the same ionic conductivity and electronic conductivity as the negative electrode active material layer 27 .

[0061] For example, the negative electrode buffer layer 25 has a conductivity of 1 mS / cm or more and 9.99*10 -9 It can have an ionic conductivity set in the range of S / cm or less.

[0062] The negative electrode buffer layer 25 is characterized by being softer than the negative electrode primer layer 23 .

[0063] The negative electrode buffer layer 25 can be formed to a thickness of 20 μm or more and 100 μm or less.

[0064] A negative electrode active material layer 27 is formed on the upper surface of the negative electrode buffer layer 25 .

[0065] The negative electrode active material layer 27 may be formed from a mixture of a sulfide-based material, a negative electrode active material, a conductive material, and a binder.

[0066] For example, the negative electrode active material layer 27 may be composed of a mixture of 8 wt % to 30 wt % of a sulfide-based material, 60 wt % to 90 wt % of a negative electrode active material, 1 wt % to 10 wt % of a conductive material, and 1 wt % to 10 wt % of a binder, based on a total weight of 100.

[0067] The negative electrode active material layer 27 can be formed to a thickness of 20 μm or more and 100 μm or less.

[0068] The solid electrolyte layer 10 is disposed on the upper surface of the negative electrode active material layer 27 .

[0069] A positive electrode 30 is formed on the upper surface of the solid electrolyte layer 10, and the positive electrode 30 is formed symmetrically with the negative electrode 20 with respect to the solid electrolyte layer 10.

[0070] Referring to FIG. 3, the positive electrode 30 is formed in the same manner as the negative electrode 20, and then stacked on the top surface of the solid electrolyte layer by flipping it upside down. However, the structure will be described based on the direction shown in FIG. 3.

[0071] Therefore, the positive electrode 30 will be described starting from the positive electrode current collector 31 located at the top of the outermost shell.

[0072] In this embodiment, the positive electrode 30 includes a positive electrode current collector 31 , a positive electrode primer layer 33 , a positive electrode buffer layer 35 , and a positive electrode active material layer 37 .

[0073] The positive electrode current collector 31 may be formed of at least one material selected from the group consisting of stainless steel, titanium, iron, nickel, aluminum, and chromium.

[0074] Such a positive electrode current collector 31 forms a surface roughness on the lower surface.

[0075] The surface roughness of the positive electrode current collector 31 is the same as the surface roughness of the negative electrode current collector 21 .

[0076] The positive electrode current collector 31 can be formed to a thickness of 15 μm or more and 20 μm or less.

[0077] A positive electrode primer layer 33 is formed on the lower surface of the positive electrode current collector 31 .

[0078] The positive electrode primer layer 33 may be made of a mixture of a carbon-based conductive material and a binder.

[0079] For example, the positive electrode primer layer 33 may be formed by mixing a conductive material and a binder in a ratio of 7:3 to 9.5:0.5.

[0080] The positive electrode primer layer 33 can be formed to a thickness of 1 μm or less.

[0081] A positive electrode buffer layer 35 is formed on the lower surface of the positive electrode primer layer 33 .

[0082] The positive electrode buffer layer 35 can be formed by mixing a sulfide-based material, a conductive material, and a binder.

[0083] For example, the positive electrode buffer layer 35 may be composed of a mixture of a sulfide-based material in a range of 60 wt % to 90 wt % based on the total weight of the positive electrode buffer layer 35, a conductive material in a range of 9 wt % to 30 wt % based on the total weight of the positive electrode buffer layer 35, and a binder in a range of 1 wt % to 10 wt % based on the total weight of the positive electrode buffer layer 35.

[0084] The positive electrode buffer layer 35 may have the same ionic conductivity and electronic conductivity as the positive electrode active material layer 37 .

[0085] For example, the positive electrode buffer layer 35 has a conductivity of 1 mS / cm or more and 9.99*10 -9 It can have an ionic conductivity set in the range of S / cm or less.

[0086] The positive electrode buffer layer 35 is characterized by being softer than the positive electrode primer layer 33 .

[0087] The positive electrode buffer layer 35 can be formed to a thickness of 1 μm or more and 5 μm or less.

[0088] A positive electrode active material layer 37 is formed on the lower surface of the positive electrode buffer layer 35 .

[0089] The positive electrode active material layer 37 can be formed from a mixture of a sulfide-based material, a positive electrode active material, a conductive material, and a binder.

[0090] For example, the positive electrode active material layer 37 may be composed of a mixture of 8 wt % to 30 wt % of a sulfide-based material, 60 wt % to 90 wt % of a positive electrode active material, 1 wt % to 10 wt % of a conductive material, and 1 wt % to 10 wt % of a binder, based on a total weight of 100.

[0091] The positive electrode active material layer 37 can be formed to a thickness of 20 μm or more and 100 μm or less.

[0092] The positive electrode active material layer 37 has a structure in which a solid electrolyte layer 10 is disposed on the lower surface thereof.

[0093] The method for manufacturing the all-solid-state battery configured as above is as follows.

[0094] 4 to 11 are diagrams sequentially illustrating a method for manufacturing an all-solid-state battery according to an embodiment of the present invention.

[0095] The method for manufacturing an all-solid-state battery according to an embodiment of the present invention includes a method of separately manufacturing the anode electrode 20 and the cathode electrode 30, and then bonding the anode electrode 20 and the cathode electrode 30 to one side and the other side of the solid electrolyte layer 10, respectively.

[0096] At this time, the negative electrode 20 is disposed on the lower surface of the solid electrolyte layer 10 , and the positive electrode 30 is disposed on the upper surface of the solid electrolyte layer 10 .

[0097] Therefore, the positive electrode 30 can be formed symmetrically with respect to the negative electrode 20 and the solid electrolyte layer 10 by stacking each material in sequence, flipping it upside down, and bonding it to the upper surface of the solid electrolyte layer 10.

[0098] Referring to FIG. 4, the upper surface of the negative electrode current collector 21 is subjected to a surface treatment to form a surface roughness.

[0099] The surface treatment may include a plasma surface treatment or a corona surface treatment.

[0100] The plasma surface treatment or corona surface treatment is a process of irradiating the upper surface of the negative electrode current collector 21 with plasma or corona to change the surface condition and roughen the surface.

[0101] Such surface treatment is intended to increase the bonding area due to surface roughness.

[0102] Referring to FIG. 5, a negative electrode primer layer 23 is formed on the upper surface of the negative electrode current collector 21 .

[0103] The negative electrode primer layer 23 is formed by wet coating, and the wet coating may include, for example, gravure coating and slot die coating.

[0104] Such a negative electrode primer layer 23 can prevent the negative electrode current collector 21 from corroding.

[0105] In addition, the negative electrode primer layer 23 is made of a mixture of a carbon-based conductive material and a binder, and the carbon-based conductive material can improve the electron conductivity.

[0106] Referring to FIG. 6, a negative electrode buffer layer 25 is formed on the upper surface of the negative electrode primer layer 23 .

[0107] The negative electrode buffer layer 25 is formed by wet coating, and the wet coating may include, for example, gravure coating and slot die coating.

[0108] The negative electrode buffer layer 25 is characterized by being softer than the negative electrode primer layer 23 .

[0109] The negative electrode buffer layer 25 allows ions and electrons to move, thereby improving the capacity.

[0110] Referring to FIG. 7, a negative electrode active material layer 27 is formed on the negative electrode buffer layer 25 .

[0111] The negative electrode active material layer 27 is characterized by having the same ionic conductivity and electronic conductivity as the negative electrode buffer layer 25 .

[0112] Referring to FIG. 8, after the negative electrode current collector 21, the negative electrode primer layer 23, the negative electrode buffer layer 25, and the negative electrode active material layer 27 are laminated as described above, a rolling process is performed.

[0113] At this time, the rolling step is carried out at a pressure set in the range of 0.1 MPa to 10 MPa.

[0114] In the negative electrode 20, due to the high flexibility of the negative electrode buffer layer 25, the physical cohesion between the negative electrode buffer layer 25 and the negative electrode active material layer 27 is increased during the rolling process.

[0115] Referring to FIG. 9, a solid electrolyte layer 10 is formed on the upper surface of the negative electrode active material.

[0116] The solid electrolyte layer 10 is formed by wet coating, and the wet coating may include, for example, gravure coating and slot die coating.

[0117] Ions can move through the solid electrolyte layer 10 .

[0118] Next, the positive electrode 30 is formed by repeating the steps shown in FIGS.

[0119] That is, a positive electrode primer layer 33 is formed on the upper surface of a positive electrode current collector 31, a positive electrode buffer layer 35 is formed on the upper surface of the positive electrode primer layer 33, and a positive electrode active material layer 37 is formed on the upper surface of the positive electrode buffer layer 35.

[0120] Referring to FIG. 10, the positive electrode 30 formed as described above is turned upside down and then stacked on the upper surface of the solid electrolyte layer 10 .

[0121] In other words, the positive electrode 30 is laminated such that the positive electrode active material layer 37 is in contact with the solid electrolyte layer 10 .

[0122] Referring to FIG. 11, the stacked negative electrode 20, solid electrolyte layer 10, and positive electrode 30 are subjected to a rolling process.

[0123] At this time, the rolling step is carried out at a pressure set in the range of 0.1 MPa to 10 MPa.

[0124] In the all-solid-state battery 1, the rolling step can improve the binding strength between the negative electrode active material, the solid electrolyte layer 10, and the positive electrode active material.

[0125] Therefore, the all-solid-state battery and the manufacturing method thereof according to the embodiment of the present invention may minimize electrode porosity that may occur after a rolling process and maximize the interfacial adhesion area between each layer by applying the anode buffer layer 25 and the cathode buffer layer 35.

[0126] As a result, the all-solid-state battery and its manufacturing method can allow ions and electrons to move uniformly above and below the electrodes, thereby improving output and durability.

[0127] In addition, the all-solid-state battery and the manufacturing method thereof according to the embodiment of the present invention can minimize deformation due to volume change of the anode active material or the cathode active material that may occur during charging and discharging, thereby improving the life characteristics.

[0128] Although the present invention has been described above with reference to preferred embodiments, it will be understood by those skilled in the art that various modifications and variations can be made to the present invention without departing from the spirit and scope of the present invention as set forth in the following claims. [Explanation of symbols]

[0129] 1: All-solid-state battery 10: Solid electrolyte layer 20: Negative electrode 21: Negative electrode current collector 23: Negative electrode primer layer 25: Negative electrode buffer layer 27: Negative electrode active material layer 30: Positive electrode 31: Positive electrode current collector 33: Positive electrode primer layer 35: Positive electrode buffer layer 37: Positive electrode active material layer

Claims

1. Sulfide solid electrolyte layer; a negative electrode including a negative electrode active material layer stacked on one surface of the solid electrolyte layer, and a negative electrode buffer layer stacked on one surface of the negative electrode active material layer; and a positive electrode including a positive electrode active material layer laminated on the other surface of the solid electrolyte layer, and a positive electrode buffer layer laminated on the other surface of the positive electrode active material layer; Including, The negative electrode is a negative electrode current collector layer forming surface roughness on one side; a negative electrode primer layer disposed on one surface of the negative electrode current collector layer, the negative electrode primer layer being made of a mixture of a carbon-based conductive material and a binder and not containing a sulfide-based material serving as a solid electrolyte; a negative electrode buffer layer disposed on one surface of the negative electrode primer layer and comprising a mixture of a sulfide-based material as a solid electrolyte, a conductive material, and a binder; and a negative electrode active material layer disposed on one surface of the negative electrode buffer layer, the negative electrode active material layer being in contact with the solid electrolyte layer and including a mixture of a sulfide-based solid electrolyte material, a negative electrode active material, a conductive material, and a binder; Including, The negative electrode buffer layer is An all-solid-state battery having the same ionic conductivity and electronic conductivity as those of the negative electrode active material layer.

2. The negative electrode current collector is 2. The all-solid-state battery according to claim 1, comprising at least one material selected from the group consisting of copper, stainless steel, titanium, iron, and nickel.

3. The negative electrode primer layer is 2. The all-solid-state battery according to claim 1, wherein the carbon-based conductive material and the binder are mixed in a ratio of 7:3 to 9.5:0.

5.

4. The negative electrode buffer layer is 2. The all-solid-state battery according to claim 1, comprising a mixture of a sulfide-based material as a solid electrolyte set in a range of 60 wt % to 90 wt % based on 100% of the total weight, a conductive material set in a range of 9 wt % to 30 wt % and a binder set in a range of 1 wt % to 10 wt %.

5. The negative electrode buffer layer is The all-solid-state battery according to claim 1 , wherein the negative electrode primer layer has a higher softness than the negative electrode primer layer.

6. The negative electrode active material layer is 2. The all-solid-state battery according to claim 1, comprising a mixture of a sulfide-based material as a solid electrolyte in a range of 8 wt % to 30 wt % based on a total weight of 100, a negative electrode active material in a range of 60 wt % to 90 wt %, a conductive material in a range of 1 wt % to 10 wt %, and a binder in a range of 1 wt % to 10 wt %.

7. The positive electrode is a positive electrode current collector having surface roughness formed on one side; a positive electrode primer layer disposed on one surface of the positive electrode current collector, the positive electrode primer layer being made of a mixture of a carbon-based conductive material and a binder and not containing a sulfide-based material serving as a solid electrolyte; a positive electrode buffer layer disposed on one surface of the positive electrode primer layer and comprising a mixture of a sulfide-based material as a solid electrolyte, a conductive material, and a binder; and a cathode active material layer disposed on one surface of the cathode buffer layer, the cathode active material layer being in contact with the solid electrolyte layer and including a mixture of a sulfide-based solid electrolyte material, a cathode active material, a conductive material, and a binder; The all-solid-state battery of claim 1 , comprising:

8. The positive electrode current collector is The all-solid-state battery according to claim 7 , comprising one or more selected from the group consisting of stainless steel, titanium, iron, nickel, aluminum, and chromium.

9. The positive electrode primer layer is The all-solid-state battery according to claim 7, wherein the carbon-based conductive material and the binder are mixed in a ratio of 7:3 to 9.5:0.

5.

10. The positive electrode buffer layer is 8. The all-solid-state battery according to claim 7, comprising a mixture of a sulfide-based material as a solid electrolyte set in a range of 60 wt % to 90 wt % based on 100% of the total weight, a conductive material set in a range of 9 wt % to 30 wt % and a binder set in a range of 1 wt % to 10 wt %.

11. The positive electrode buffer layer is The all-solid-state battery according to claim 7 , wherein the positive electrode primer layer has a higher softness than the positive electrode primer layer.

12. The positive electrode buffer layer is The all-solid-state battery according to claim 7 , having the same ionic conductivity and electronic conductivity as those of the positive electrode active material layer.

13. The positive electrode active material layer is 8. The all-solid-state battery according to claim 7, comprising a mixture of a sulfide-based material as a solid electrolyte in a range of 8 wt % to 30 wt % based on a total weight of 100, a positive electrode active material in a range of 60 wt % to 90 wt %, a conductive material in a range of 1 wt % to 10 wt %, and a binder in a range of 1 wt % to 10 wt %.

14. A method for manufacturing an all-solid-state battery, A first step of forming a negative electrode including a negative electrode active material layer and a negative electrode buffer layer; a second step of forming a sulfide-based solid electrolyte layer on one surface of the negative electrode; A third step of forming a positive electrode including a positive electrode active material layer and a positive electrode buffer layer; and a fourth step of bonding the positive electrode to the other surface of the solid electrolyte layer; Including, The first stage comprises: forming a surface roughness on one surface of the negative electrode current collector through a surface treatment; forming a negative electrode primer layer on one surface of the negative electrode current collector by wet coating; forming a negative electrode buffer layer having higher flexibility than the negative electrode primer layer by wet coating on one surface of the negative electrode primer layer; forming a negative electrode active material layer on one surface of the negative electrode buffer layer, the negative electrode active material layer having the same ionic conductivity and electronic conductivity as the negative electrode buffer layer; and rolling the stacked negative electrode current collector, negative electrode primer layer, negative electrode buffer layer, and negative electrode active material layer; Including, the negative electrode primer layer is made of a mixture of a carbon-based conductive material and a binder, and does not contain a sulfide-based material that is a solid electrolyte.

15. The second stage comprises: The method of claim 14 , wherein the solid electrolyte layer is formed on one surface of the negative electrode active material layer by wet coating.

16. The third stage is forming a surface roughness on one surface of a positive electrode current collector through a surface treatment; forming a positive electrode primer layer made of a mixture of a carbon-based material and a binder by wet coating on one surface of the positive electrode current collector; forming a positive electrode buffer layer having a softer property than the positive electrode primer layer on one surface of the positive electrode primer layer; forming a positive electrode active material layer on one surface of the positive electrode buffer layer, the positive electrode active material layer having the same ionic conductivity and electronic conductivity as the positive electrode buffer layer; and rolling the stacked positive electrode current collector, positive electrode primer layer, positive electrode buffer layer, and positive electrode active material layer; Including, 15. The method for producing an all-solid-state battery according to claim 14, wherein the negative electrode primer layer is made of a mixture of a carbon-based conductive material and a binder and does not contain a sulfide-based material that is a solid electrolyte, and the positive electrode primer layer is made of a mixture of a carbon-based conductive material and a binder and does not contain a sulfide-based material that is a solid electrolyte.

17. The fourth stage is after inverting the positive electrode upside down, contacting the solid electrolyte layer with the positive electrode active material layer of the positive electrode; and rolling the negative electrode, the solid electrolyte layer, and the positive electrode; The method for producing the all-solid-state battery according to claim 14, comprising:

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