Manufacturing method for all-solid-state batteries

Abstract

The present invention relates to a method for producing an all-solid-state battery which not only has a simple production process and allows for stacking a larger number of electrodes in a desired size, but also allows for easy alignment of the electrodes.

Description

[Technical field]

[0001] This application claims the benefit of priority to Korean Patent Application No. 10-2022-0003900 dated January 11, 2022, and all contents disclosed in the documents of the Korean patent application are incorporated as part of this specification.

[0002] The present invention relates to a method for producing an all-solid-state battery. [Background technology]

[0003] A secondary battery is a device that converts external electrical energy into chemical energy, stores it, and produces electricity when needed. It is also called a rechargeable battery because it can be recharged multiple times. Commonly used secondary batteries include lead-acid batteries, nickel-cadmium batteries (NiCd), nickel-metal hydride batteries (NiMH), and lithium secondary batteries. Secondary batteries offer both economic and environmental advantages over disposable primary batteries.

[0004] Meanwhile, as wireless communication technology gradually develops, there is a demand for portable devices or automobile accessories to be lighter, thinner, and smaller, and the demand for secondary batteries to be used as energy sources for these devices is increasing. In particular, hybrid cars and electric cars have been put to practical use in order to prevent environmental pollution, and research is emerging to use secondary batteries in these next-generation automobile batteries to reduce manufacturing costs and weight and extend life. Among various secondary batteries, lithium secondary batteries, which are lightweight, have high energy density and operating potential, and have a long cycle life, have recently been in the spotlight.

[0005] In general, a lithium secondary battery is manufactured by mounting an electrode assembly including a negative electrode, a positive electrode, and a separator inside a cylindrical or rectangular metal can or a pouch-type case made of an aluminum laminate sheet, and injecting an electrolyte into the electrode assembly.

[0006] Conventionally, liquid electrolytes in which lithium salts are dissolved in non-aqueous organic solvents have been mainly used as electrolytes for lithium secondary batteries. However, such liquid electrolytes are likely to cause deterioration of electrode materials and volatilization of organic solvents, and may cause combustion or explosion due to temperature rises in the surroundings and the battery itself, and may leak, making it difficult to realize various types of lithium secondary batteries with high safety.

[0007] Meanwhile, all-solid-state batteries using a solid electrolyte have the advantage that they do not use organic solvents and therefore allow the electrode assembly to be manufactured in a safe and simple manner.

[0008] All-solid-state batteries can be divided into oxide-based, polymer-based, and sulfide-based batteries depending on the raw material of the solid electrolyte. Sulfide-based all-solid-state batteries have been drawing attention because they have better lithium ion conductivity than other types of batteries. However, despite their excellent characteristics, they have the disadvantage of being inferior in lifespan and output compared to batteries that use existing liquid electrolytes, as they have higher ion conductivity and electrical resistance between the positive and negative electrodes than liquid batteries.

[0009] In order to improve the life and output of the unit cell, it is possible to consider using different types of solid electrolyte positive and negative electrodes, different solid electrolytes, and different assembly methods. In particular, considering that the life of the unit cell depends on the lithium content of the negative electrode, forming a secondary battery using lithium metal as the negative electrode is effective in increasing the life.

[0010] Lithium metal was not used in secondary batteries that used existing electrolytes due to safety issues caused by the reactivity of lithium metal itself, but with solid electrolytes, safety can be ensured as no electrolyte is used. Regarding dendrites that are formed when lithium metal is used, various research has been conducted to suppress their formation.

[0011] A unit cell including a solid electrolyte can improve the performance of the unit cell by reducing the interface resistance by applying pressure to the positive electrode, the solid electrolyte, and the negative electrode. However, unlike conventional batteries using copper or graphite as the negative electrode, lithium metal is soft, so the capacity, performance, and safety of the unit cell can vary depending on the degree and time of pressure. When lithium metal is applied with high pressure, it may warp and react with the solid electrolyte, causing a short circuit in the cell. Therefore, since it is not possible to apply pressure to the negative electrode, the positive electrode, and the solid electrolyte all at once, the manufacturing process is complicated, and it is difficult to align the electrodes to be stacked.

[0012] Therefore, there is a need to study a manufacturing method that can solve the above problems. [Prior art documents] [Patent documents]

[0013] [Patent Document 1] JP 2019-200890 A [Patent Document 2] JP 2018-181451 A Summary of the Invention [Problem to be solved by the invention]

[0014] An object of the present invention is to provide a method for manufacturing an all-solid-state battery that allows a larger number of electrodes to be stacked in a desired size, facilitates alignment between the electrodes, and is a simple manufacturing method. [Means for solving the problem]

[0015] In order to achieve the above objective, The present invention includes the steps of: (1) preparing an all-solid-state electrolyte layer sheet; (2) dividing the all-solid-state electrolyte layer sheet so that two electrodes are arranged at a distance from each other in the width direction, and the two electrode pairs arranged at a distance from each other are arranged at least two apart in the length direction; (3) laminating an electrode having one polarity in a zigzag pattern on the front surface of the partitioned all-solid-state electrolyte layer sheet; (4) laminating an electrode having a polarity opposite to that of the electrode on the front surface in a section of the rear surface of the all-solid-state electrolyte layer sheet where an electrode having one polarity is not laminated on the front surface; and (5) folding and stacking the all-solid-state electrolyte layer sheet with the electrodes laminated thereon so that the electrodes are not in contact with each other.

[0016] In an embodiment of the present invention, the step (3) of zigzag laminating an electrode having one polarity may include laminating an electrode having one polarity by selecting any one of a group of partition units diagonally connected to each other among partition units partitioned on a front surface of the all-solid-state electrolyte layer sheet.

[0017] In one embodiment of the present invention, after step (2) and before step (3), or after step (4) and before step (5), the method may further include cutting the widthwise separated portions of the all-solid-state electrolyte layer sheet, on which the electrodes are disposed, in a zigzag pattern based on a center line of the lengthwise separated portions.

[0018] In an embodiment of the present invention, the cut all-solid-state electrolyte layer sheet may be cut at a longitudinal end portion of the cut portion adjacent to an electrode, and the cut portion adjacent to another electrode may be folded to stack the electrodes in sequence to different heights.

[0019] In one embodiment of the present invention, the electrodes may be formed by alternately stacking negative and positive electrodes.

[0020] In an embodiment of the present invention, the uppermost and lowermost electrodes of the electrode stack in which the electrodes are stacked may be end electrodes in which an electrode active material is applied to only one surface of a current collector.

[0021] In one embodiment of the present invention, the top and bottom edge electrodes may be of the same polarity.

[0022] In one embodiment of the present invention, the electrodes excluding the end electrodes may be double-sided electrodes in which electrode active materials of the same polarity are applied to both sides of a current collector.

[0023] In one embodiment of the present invention, the method may further include a pressurizing step after step (5).

[0024] In one embodiment of the present invention, the solid electrolyte of the all-solid electrolyte layer sheet may include a sulfide-based solid electrolyte.

[0025] In an embodiment of the present invention, when the electrode having one polarity is a negative electrode, the negative electrode active material may be lithium metal or a lithium alloy. Effect of the Invention

[0026] The method for producing an all-solid-state battery of the present invention has a simple production process, and not only can it stack a larger number of electrodes in a desired size, but it also has the effect of facilitating alignment between the electrodes. [Brief description of the drawings]

[0027] [Figure 1] 1 is a diagram showing a partitioned all-solid-state electrolyte layer sheet. [Diagram 2] 1 is a diagram showing a partitioned all-solid-state electrolyte layer sheet. [Diagram 3] 1 is a view showing the front surface of an all-solid-state electrolyte layer sheet on which electrodes having one polarity are laminated in a zigzag pattern according to an embodiment of the present invention. [Figure 4] FIG. 4 is a diagram showing the rear surface of an all-solid-state electrolyte layer sheet in which an electrode having a polarity different from that of the electrode on the front surface is laminated in a section of the all-solid-state electrolyte layer sheet in FIG. 3 where no electrode is laminated on the front surface. [Diagram 5] 1 is a diagram showing an all-solid-state electrolyte layer sheet in which a positive electrode and a negative electrode are laminated. [Figure 6] 1 is a diagram showing an all-solid-state electrolyte layer sheet in which a positive electrode and a negative electrode are laminated. [Figure 7] 6 is a cross-sectional view taken along line AA in FIG. 5. [Figure 8] 1 is a diagram showing an all-solid-state battery manufactured by a method for manufacturing an all-solid-state battery according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0028] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described in detail with reference to the accompanying drawings, in order to enable those skilled in the art to easily practice the present invention. However, the present invention may be embodied in several different forms and is not limited to the embodiments set forth herein.

[0029] In order to clearly describe the present invention, parts that are not relevant to the description will be omitted, and the same reference numerals will be used throughout the specification to refer to the same or similar components.

[0030] Furthermore, the terms and words used in this specification and claims should not be interpreted in a limited manner based on their ordinary or dictionary meaning, but should be interpreted in a meaning and concept that corresponds to the technical idea of ​​the present invention, based on the principle that an inventor can appropriately define the concept of a term in order to explain his / her invention in the best possible manner.

[0031] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention may, however, be embodied in several different forms and should not be construed as limited to the embodiments set forth herein.

[0032] Among conventional all-solid-state batteries, those that use sulfide-based solid electrolytes as the solid electrolyte have a problem with difficult interface contact due to the occurrence of many pores inside the electrodes when manufactured using the roll-to-roll pressing method. To solve this problem, a three-dimensional pressing method was carried out using hydrostatic pressing, but the size of the battery that could be pressed was limited due to the size of the chamber of the isostatic pressing equipment.

[0033] In addition, when the negative electrode is made of lithium metal, the hardness of the lithium metal is low, and therefore, when the negative electrode, the positive electrode, and the all-solid-state electrolyte layer sheet are pressed together, the applied pressure may be different. For this reason, when the negative electrode is made of lithium metal, it is not possible to pressurize the negative electrode, the positive electrode, and the all-solid-state electrolyte layer sheet at once. In other words, a complex process must be repeated to manufacture an all-solid-state battery, in which the negative electrode is laminated on the all-solid-state electrolyte layer sheet and then pressed, the all-solid-state electrolyte layer sheet is laminated thereon and pressed, and the positive electrode is laminated thereon and pressed, and the repeated process causes a problem of difficulty in aligning the laminated electrodes.

[0034] Therefore, the present invention aims to provide a method for producing an all-solid-state battery that can solve the above problems.

[0035] The present invention relates to a method for producing an all-solid-state battery, specifically, (1) preparing an all-solid-state electrolyte layer sheet; (2) dividing the all-solid-state electrolyte layer sheet so that two electrodes are arranged at a distance from each other in the width direction, and the two electrode pairs arranged at a distance from each other are arranged at least two apart in the length direction; (3) laminating an electrode having one polarity in a zigzag pattern on the front surface of the partitioned all-solid-state electrolyte layer sheet; (4) laminating an electrode having a polarity opposite to that of the electrode on the front surface in a section of the rear surface of the all-solid-state electrolyte layer sheet where an electrode having one polarity is not laminated on the front surface; and (5) folding and stacking the electrode-laminated all-solid-state electrolyte layer sheet so that the electrodes are not in contact with each other;

[0036] The step (1) is a step of preparing an all-solid-state electrolyte layer sheet.

[0037] The solid electrolyte of the all-solid electrolyte layer sheet may preferably include a sulfide-based solid electrolyte.

[0038] The sulfide-based solid electrolyte may include Li-PS-based glass or Li-PS-based glass ceramics, which contain sulfur (S) and have ionic conductivity of a metal belonging to Group 1 or Group 2 of the periodic table. Non-limiting examples of such sulfide-based solid electrolytes include Li2S-P2S5, Li2S-LiI-P2S5, Li2S-LiI-Li2O-P2S5, Li2S-LiBr-P2S5, Li2S-Li2O-P2S5, Li2S-Li3PO4-P2S5, Li2S-P2S5, Li2S-P2S5-SiS2, Li2S-P2S5-SnS, Li2S-P2S5-Al2S3, Li2S-GeS2, and Li2S-GeS2-ZnS, and may include one or more of these. However, the present invention is not limited thereto.

[0039] The method for producing the all-solid-state electrolyte layer sheet is not particularly limited as long as it is a method used in the art. For example, the all-solid-state electrolyte layer sheet may be produced by preparing a slurry containing the sulfide-based solid electrolyte, applying the slurry onto a sheet, and drying and rolling the sheet.

[0040] The step (2) is a step of dividing the all-solid-state electrolyte layer sheet so that two electrodes are spaced apart in the width direction and two or more electrode pairs spaced apart are spaced apart in the length direction. FIG. 1 is a diagram showing the divided all-solid-state electrolyte layer sheet 110.

[0041] The two electrode pairs may be disposed at a distance of two or more in the longitudinal direction, and the number of electrode pairs to be disposed is not particularly limited, and the electrode pairs may be disposed in the longitudinal direction of the all-solid-state electrolyte layer sheet by the number of electrode pairs to be stacked as shown in Fig. 2. Thus, the all-solid-state electrolyte layer sheet 110 can be partitioned by the number of electrode pairs to be stacked.

[0042] The step (3) is a step of laminating an electrode having one polarity in a zigzag pattern on the front surface of the partitioned all-solid-state electrolyte sheet.

[0043] 3 is a diagram showing the front surface of an all-solid-state electrolyte layer sheet 110 having electrodes having one polarity laminated in a zigzag pattern according to an embodiment of the present invention. The electrodes having one polarity may be a positive electrode or a negative electrode, and FIG. 3 illustrates a negative electrode 130.

[0044] The zigzag lamination of the electrodes having one polarity refers to laminating an electrode having one polarity by selecting any one of the compartment unit groups diagonally connected to each other among the compartment units partitioned on the front surface of the all-solid-state electrolyte layer sheet, i.e., there are two compartment unit groups diagonally connected to each other among the compartment units partitioned on the front surface of the all-solid-state electrolyte layer sheet, and only one of these groups is selected and laminated.

[0045] When the electrodes are laminated as described above, the electrodes are not laminated to any one of the compartment units adjacent in the longitudinal direction and the width direction to the one of the compartment units to which the electrodes are laminated.

[0046] The step (4) is a step of laminating an electrode having a polarity opposite to that of the electrode on the front surface in a section of the rear surface of the all-solid-state electrolyte sheet where an electrode having one polarity is not laminated on the front surface.

[0047] 4 is a view showing the rear surface of an all-solid-state electrolyte layer sheet 110 according to an embodiment of the present invention. An electrode is laminated on the rear surface in a section where no electrode is laminated on the front surface, and the electrode laminated on the rear surface may have a polarity different from that of the electrode on the front surface. The electrodes shown in FIG. 4 are examples of positive electrodes 120 and 123.

[0048] That is, in the all-solid-state electrolyte layer sheet 110 in which the positive electrodes 120, 123 and the negative electrode 130 are laminated according to an embodiment of the present invention, the negative electrode 130 may be laminated on the front surface, and the positive electrodes 120, 123 may be laminated on the rear surface.

[0049] In addition, in the all-solid-state electrolyte layer sheet 110 having the positive electrodes 120, 123 and the negative electrode 130 laminated thereon according to another embodiment of the present invention, the positive electrodes 120, 123 may be laminated on the front surface, and the negative electrode 130 may be laminated on the rear surface.

[0050] 5 is a diagram showing an all-solid-state electrolyte layer sheet 110 on which positive electrodes 120 and 123 and a negative electrode 130 are laminated. In this case, the negative electrode 130 is laminated on the front surface of the all-solid-state electrolyte layer sheet 110, and the positive electrodes 120 and 123 are laminated on the rear surface of the all-solid-state electrolyte layer sheet 110.

[0051] As described above in step (2), the number of electrode pairs arranged on the all-solid-state electrolyte layer sheet 110 is not particularly limited, so the number of negative electrodes 130 and positive electrodes 120, 123 arranged as shown in FIG. 6 is not limited.

[0052] FIG. 7 is a cross-sectional view taken along line AA in FIG. 5, showing that the negative electrode 130 is laminated on the front surface of the all-solid-state electrolyte layer sheet 110, and the positive electrodes 120 and 123 are laminated on the rear surface.

[0053] The step (5) is a step of folding and stacking the all-solid-state electrolyte layer sheet having the electrodes laminated thereon so that the electrodes are not in contact with each other, and a stack cell type all-solid-state battery can be manufactured in the step (5).

[0054] At this time, the electrodes may be stacked to different heights.

[0055] In order to fold and stack the electrodes so that they are not in contact with each other, after step (2) and before step (3), or after step (4) and before step (5), a step of cutting the widthwise separation portion of the all-solid-state electrolyte layer sheet on which the electrodes are disposed in a zigzag pattern based on a center line of the lengthwise separation portion may be further included.

[0056] The cut all-solid-state electrolyte layer sheet 110 may be folded at the cut portion 140 at the end of the longitudinal direction to separate the adjacent electrodes from the adjacent electrodes, and the electrodes may be stacked in sequence at different heights.

[0057] By repeating the above process, the negative electrodes 130 and the positive electrodes 120 can be stacked alternately.

[0058] The separation distance is not particularly limited, and it is sufficient if the adjacent electrodes do not come into contact with each other when the separation portion is folded.

[0059] The folding process of the spacer without the double folded portion will be described with reference to FIG.

[0060] First, the cut all-solid-state electrolyte layer sheet 110 is folded inwardly along a vertical line 151 with respect to the front surface of the all-solid-state electrolyte layer sheet, with the uncut part of the electrode adjacent to the cut part 140 at the end of the length direction being the center line of the longitudinal separation part of the all-solid-state electrolyte layer sheet 110, and the separation part adjacent to the other electrode being the center line of the longitudinal separation part of the all-solid-state electrolyte layer sheet 110 being the center line of the longitudinal separation part of the all-solid-state electrolyte layer sheet 110. In this process, the positive electrode 123, the all-solid-state electrolyte layer sheet 110, and the negative electrode 130 are stacked in this order. Thereafter, the stack of the positive electrode 123, the all-solid-state electrolyte layer sheet 110, and the negative electrode 130 is folded outwardly along a horizontal line 152. In this process, the positive electrode 123, the all-solid-state electrolyte layer sheet 110, the negative electrode 130, the all-solid-state electrolyte layer sheet 110, and the positive electrode 120 are stacked in this order. Thereafter, the process of folding inward along the vertical line 151 and the process of folding outward along the horizontal line 152 are repeated to manufacture an all-solid-state battery in which the negative electrode 130 and the positive electrode 120 are alternately stacked. Specifically, for example, the process of folding inward along the vertical line 151 and folding outward along the horizontal line 152 is repeated in the direction of the arrows shown in FIG.

[0061] By repeating the above process, the negative electrodes 130 and the positive electrodes 120 can be stacked alternately.

[0062] The top and bottom electrodes of the electrode stack in which the electrodes are stacked are end electrodes in which an electrode active material is applied to only one surface of a current collector, and the top and bottom end electrodes of the all-solid-state battery manufactured by the manufacturing method according to an embodiment of the present invention have the same polarity.

[0063] The electrodes other than the end electrodes are double-sided electrodes in which electrode active materials of the same polarity are applied to both sides of a current collector.

[0064] FIG. 8 is a diagram showing an all-solid-state battery 100 manufactured by a method for manufacturing an all-solid-state battery according to an embodiment of the present invention, in which the uppermost and lowermost portions are end surface positive electrodes 123.

[0065] Referring to FIG. 8, among the electrodes excluding the top and bottom end positive electrodes 123, the positive electrode 120 may be a double-sided positive electrode 120 in which a positive electrode active material 121 is applied to both sides of a positive electrode current collector 122, and the negative electrode 130 may be a double-sided negative electrode 130 in which a negative electrode active material 131 is applied to both sides of a negative electrode current collector 132.

[0066] The all-solid-state battery is a lithium secondary battery, and is not limited to a positive electrode or a negative electrode, and may be a lithium-air battery, a lithium oxide battery, a lithium-sulfur battery, or a lithium metal battery.

[0067] The positive electrode current collector 122 is for supporting the positive electrode active material 121 and is not particularly limited as long as it has excellent conductivity and is electrochemically stable in the voltage region of a lithium secondary battery. For example, the positive electrode current collector 122 may be any one metal selected from the group consisting of copper, aluminum, stainless steel, titanium, silver, palladium, nickel, alloys thereof, and combinations thereof, and the stainless steel may be surface-treated with carbon, nickel, titanium, or silver, and the alloy may preferably be an aluminum-cadmium alloy, and may also be calcined carbon, a non-conductive polymer surface-treated with a conductive material, or a conductive polymer.

[0068] The positive electrode current collector 122 may have fine irregularities on its surface to strengthen the bonding force with the positive electrode active material 121, and may be in various forms such as a film, a sheet, a foil, a mesh, a net, a porous body, a foam, a nonwoven fabric, etc.

[0069] The positive electrode active material 121 may include a conductive material and a binder, optionally in addition to the positive electrode active material 121 .

[0070] The positive electrode active material 121 may vary depending on the type of solid-state battery. For example, the positive electrode active material 121 may be a layered compound such as lithium cobalt oxide (LiCoO2) or lithium nickel oxide (LiNiO2) or a compound substituted with one or more transition metals; 1+x Mn 2-x O4 (0≦x≦0.33), lithium manganese oxides such as LiMnO3, LiMn2O3, LiMnO2; lithium copper oxide (Li2CuO2); vanadium oxides such as LiV3O8, V2O5, Cu2V2O7; chemical formula LiNi 1-x M x Lithium nickel oxide with Ni site represented by O2 (M=Co, Mn, Al, Cu, Fe, Mg, B or Ga; 0.01≦x≦0.3); chemical formula LiMn 2-x M x Lithium manganese composite oxide represented by Li2Mn3MO8 (M=Fe, Co, Ni, Cu, or Zn) or LiNi x Mn 2-x Lithium manganese oxide with spinel structure represented by O4; LiCoPO4; LiFePO4; Elemental sulfur (S8); Li2S n (n=1), organic sulfur compounds or carbon-sulfur polymers (C2S x ) n The sulfur-based compounds may include, but are not limited to, sulfur-based compounds such as: x=2.5 to 50, n=2).

[0071] The conductive material is a material that electrically connects the electrolyte and the positive electrode active material 121 and serves as a path for electrons to move from a current collector to the positive electrode active material. Any conductive material that does not cause chemical changes in a lithium secondary battery and has porosity and conductivity can be used without any restrictions.

[0072] For example, the conductive material may be a porous carbon-based material, such as carbon black, graphite, graphene, activated carbon, carbon fiber, metal fiber such as metal mesh, metal powder such as copper, silver, nickel, aluminum, or organic conductive material such as polyphenylene derivatives. The conductive materials may be used alone or in combination.

[0073] Currently, commercially available conductive materials include acetylene black series (Chevron Chemical Company or Gulf Oil Company products, etc.), Ketjen Black EC series (Armak Company products), Vulcan XC-72 (Cabot Company products), and Super P (MMM Company products), etc. Examples include acetylene black, carbon black, and graphite.

[0074] In addition, the positive electrodes 120 and 123 may further include a binder. The binder enhances the adhesive strength between the components constituting the positive electrodes 120 and 123 and between them and the current collector, and any binder known in the art may be used.

[0075] For example, the binder may be one or a mixture or copolymer of two or more selected from the group consisting of fluororesin-based binders including polyvinylidenefluoride (PVdF) or polytetrafluoroethylene (PTFE); rubber-based binders including styrene butadiene rubber (SBR), acrylonitrile butadiene rubber, and styrene-isoprene rubber; cellulose-based binders including carboxyl methyl cellulose (CMC), starch, hydroxypropyl cellulose, and regenerated cellulose; polyalcohol-based binders; polyolefin-based binders including polyethylene and polypropylene; polyimide-based binders; polyester-based binders; and silane-based binders.

[0076] In addition, the negative electrode 130 may contain a conductive material and a binder, if necessary, like the positive electrodes 120 and 123. In this case, the negative electrode current collector 132, the conductive material, and the binder are the same as those described above.

[0077] The negative active material 131 according to an embodiment of the present invention may be in the form of lithium metal, lithium alloy, or a free negative electrode.

[0078] The negative electrode free form may include only the negative electrode current collector 132, or may have a structure in which a carbon layer containing a binder is coated on the negative electrode current collector.

[0079] After the step (5), a step of pressurizing the all-solid-state battery 100 manufactured by the manufacturing method may be further performed.

[0080] The pressurizing conditions are not particularly limited, and the pressurizing conditions used in the production of all-solid-state batteries can be used.

[0081] The method for manufacturing an all-solid-state battery according to an embodiment of the present invention has an advantage of being simple in the manufacturing process, since the process of folding and stacking is repeated so that the electrodes are stacked at different heights without contacting each other. Also, the manufacturing process is simple in that the manufactured all-solid-state battery can be pressed all at once, whereas in the conventional method, pressure was applied after each process of stacking the positive electrode, the negative electrode, and the all-solid-state electrolyte layer sheet. Also, it has an advantage of being possible to stack more layers of electrodes in various sizes, and by arranging the positive electrode and the negative electrode at designated positions of the all-solid-state electrolyte layer sheet, it is easy to align the positive electrode and the negative electrode.

[0082] Those skilled in the art will understand that the present invention may be embodied in modified forms without departing from the essential characteristics of the present invention. Therefore, the disclosed method should be considered in an explanatory rather than restrictive manner. The scope of the present invention is defined in the claims rather than the above description, and all differences within the scope of the equivalents should be interpreted as being included in the present invention. [Explanation of symbols]

[0083] 100: All-solid-state battery 110: All-solid electrolyte layer sheet 120: Double-sided positive electrode 121: Positive electrode active material 122: Positive electrode current collector 123: Positive end 130: Double-sided negative electrode 131:Negative electrode active material 132:Negative electrode current collector 140: Cutting section 151: Vertical line 152: Horizontal line

Claims

1. (1) preparing an all-solid-state electrolyte layer sheet; (2) dividing the all-solid-state electrolyte layer sheet so that two electrodes are arranged at a distance from each other in the width direction, and the two electrode pairs arranged at a distance from each other are arranged at least two apart in the length direction; (3) laminating an electrode having one polarity in a zigzag pattern on the front surface of the partitioned all-solid-state electrolyte layer sheet; (4) laminating an electrode having a polarity opposite to that of the electrode on the front surface in a section of the rear surface of the all-solid-state electrolyte layer sheet where an electrode having one polarity is not laminated on the front surface; and (5) folding and stacking the electrode-laminated all-solid-state electrolyte layer sheet so that the electrodes are not in contact with each other; The step (3) of zigzag laminating electrodes having one polarity includes: A method for manufacturing an all-solid-state battery, comprising: selecting any one of a group of diagonally connected partition units among the partition units partitioned on the front surface of the all-solid-state electrolyte layer sheet; and laminating an electrode having one polarity thereon.

2. 2. The method of claim 1, further comprising: cutting the widthwise separated portions of the all-solid-state electrolyte layer sheet on which the electrodes are disposed in a zigzag pattern based on a center line of the lengthwise separated portions after the step (2) and before the step (3), or after the step (4) and before the step (5).

3. 3. The method for manufacturing an all-solid-state battery according to claim 2, wherein the cut all-solid-state electrolyte layer sheet is folded at a cut portion adjacent to an electrode at a longitudinal end portion thereof so that the cut portions are adjacent to other electrodes as uncut separated portions, and the electrodes are sequentially stacked to different heights.

4. The method for producing an all-solid-state battery according to claim 1 or 3, wherein each of the electrodes is formed by alternately stacking negative electrodes and positive electrodes.

5. 2. The method for producing an all-solid-state battery according to claim 1, wherein the uppermost and lowermost electrodes of the electrode stack in which the electrodes are stacked are end electrodes in which an electrode active material is applied to only one surface of a current collector.

6. The method for producing an all-solid-state battery according to claim 5 , wherein the uppermost and lowermost end electrodes have the same polarity.

7. The method for producing an all-solid-state battery according to claim 5 , wherein the electrodes other than the end electrodes are double-sided electrodes in which electrode active materials of the same polarity are applied to both sides of a current collector.

8. The method for manufacturing an all-solid-state battery according to claim 1 , further comprising the step of applying pressure after the step (5).

9. The method for producing an all-solid-state battery according to claim 1 , wherein the solid electrolyte of the all-solid-state electrolyte layer sheet includes a sulfide-based solid electrolyte.

10. 2 . The method for manufacturing an all-solid-state battery according to claim 1 , wherein when the electrode having one polarity is a negative electrode, the negative electrode active material is lithium metal or a lithium alloy.

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