All-solid rechargeable battery manufacturing method

Abstract

An all-solid rechargeable battery manufacturing method is provided. The all-solid rechargeable battery manufacturing method, according to one embodiment, comprises: a first step for forming a first stack by stacking a first solid electrolyte layer on a first negative electrode; a second step for stacking a positive electrode on the first solid electrolyte layer of the first stack; a third step for stacking a gasket on the first solid electrolyte layer so as to be spaced apart from the positive electrode; and a fourth step for forming a finishing part in a gap set between the positive electrode and the gasket.

Description

Manufacturing method of all-solid-state secondary battery

[0001] The present disclosure relates to a method for manufacturing an all-solid-state secondary battery.

[0002] Recent industrial demands have led to the active development of batteries with high energy density and safety. For example, lithium-ion batteries are being used not only in information and communication devices, but also in the automotive sector. Safety is particularly important in the automotive sector, as it is directly related to life.

[0003] Lithium-ion batteries currently on the market use electrolytes containing flammable organic solvents, which poses a risk of overheating and fire in the event of a short circuit. To address this issue, all-solid-state secondary batteries using solid electrolytes are being proposed.

[0004] All-solid-state secondary batteries do not use flammable organic solvents, significantly reducing the risk of fire or explosion even if a short circuit occurs. Therefore, these all-solid-state batteries significantly improve safety compared to lithium-ion batteries that use electrolytes.

[0005] The above-described information disclosed in the background technology of this invention is only intended to improve understanding of the background of the present disclosure and may therefore include information that does not constitute prior art.

[0006] One embodiment provides a method for manufacturing an all-solid-state secondary battery that prevents cracking of the positive electrode during pressurization by filling a seal between the positive electrode and a gasket.

[0007] A method for manufacturing an all-solid-state secondary battery according to one embodiment includes a first step of forming a first laminate by laminating a first solid electrolyte layer on a first negative electrode, a second step of laminating a positive electrode on the first solid electrolyte layer of the first laminate, a third step of laminating a gasket on the first solid electrolyte layer and spaced apart from the positive electrode, and a fourth step of forming a closing portion in a gap established between the positive electrode and the gasket.

[0008] The fourth step may form the closing part with the positive electrode active material of the positive electrode.

[0009] The fourth step may form the closing portion with the solid electrolyte of the first solid electrolyte layer.

[0010] The fourth step may be formed by any one of powder coating, slurry spray coating, and slurry coating.

[0011] The fourth step may further include a step of pressing the anode, the gasket and the closing portion to fill the gap with the closing portion.

[0012] A method for manufacturing an all-solid-state secondary battery according to one embodiment may further include a fifth step of forming a second laminate by laminating a second solid electrolyte layer on a second negative electrode, and a sixth step of laminating the second solid electrolyte layer of the second laminate on the positive electrode, the closing portion, and the gasket.

[0013] The sixth step may further include a step of pressing the second laminate to pressurize the anode, the gasket, and the finishing part to fill the gap with the finishing part.

[0014] One embodiment prevents cracks from forming at the ends of the anode during pressurization by filling the gap established between the anode and the gasket on one side of the solid electrolyte layer with a sealing member. Furthermore, since the anode and cathode substrate tabs and connecting portions are positioned on the gasket, cracks and side reactions are prevented at the anode and cathode substrate tabs and connecting portions during isostatic pressurization. This prevents initial short-circuiting of the cell.

[0015] Figure 1 is a cross-sectional view showing an all-solid-state secondary battery according to one embodiment.

[0016] FIG. 2 is a cross-sectional view showing the formation of a lithium metal layer of an all-solid-state secondary battery according to one embodiment.

[0017] FIG. 3 is a cross-sectional view of a method for manufacturing an all-solid-state secondary battery according to a first embodiment of the present invention, in which a positive electrode is formed on a first laminated body in which a first solid electrolyte layer is laminated on a negative electrode.

[0018] Figure 4 is a cross-sectional view of forming a gasket in the first laminate of Figure 3.

[0019] Fig. 5 is a cross-sectional view of a closure formed between the anode and the gasket of the first laminate of Fig. 4.

[0020] Figure 6 is a plan view of an all-solid-state secondary battery according to the first embodiment of the present invention.

[0021] FIG. 7 is a cross-sectional view of a method for manufacturing an all-solid-state secondary battery according to a second embodiment of the present invention, in which a second laminate is laminated on the monocell of FIG. 5 to form a bicell.

[0022] Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings so that those skilled in the art can easily implement the present invention. The present invention may be implemented in various different forms and is not limited to the embodiments described herein.

[0023] Additionally, throughout the specification, whenever a part is said to "include" a component, this does not mean that it excludes other components, but rather that it may include other components, unless otherwise specifically stated.

[0024] To clearly illustrate various layers and regions in the drawings, their thicknesses are enlarged, and similar parts are designated by the same drawing reference numerals throughout the specification. When an element such as a layer, film, region, or plate is said to be "over" or "on" another element, this includes not only the case where it is "directly over" the other element, but also the case where there is another element in between. Conversely, when an element is said to be "directly over" another element, it means that there is no other element in between.

[0025] Furthermore, the term "layer" here includes not only shapes formed on the entire surface when observed in a plan view, but also shapes formed on a portion of the surface. Here, "or" is not interpreted in an exclusive sense; for example, "A or B" is interpreted to include A, B, A+B, etc.

[0026] Cathode for all-solid-state secondary batteries

[0027] In one embodiment, a positive electrode for an all-solid-state secondary battery is provided, comprising a current collector and a positive electrode active material layer positioned on the current collector, wherein the positive electrode active material layer comprises at least one of a positive electrode active material, a sulfide-based solid electrolyte, a binder, and a conductive material. However, without limitation thereto, the positive electrode for an all-solid-state secondary battery may comprise more or less components than the components described above.

[0028] In one embodiment, the positive electrode for the all-solid-state secondary battery is manufactured by applying a positive electrode composition including at least one of a positive electrode active material, a sulfide-based solid electrolyte, a binder, and a conductive agent to a current collector, followed by drying and rolling.

[0029] positive electrode active material

[0030] The above-mentioned positive electrode active material can be applied without limitation as long as it is generally used in all-solid-state secondary batteries. For example, the above-mentioned positive electrode active material may be a compound capable of reversible intercalation and deintercalation of lithium, and may include a compound represented by any one of the following chemical formulas.

[0031] Li a A 1-b X b D2(0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.5);

[0032] Li a A 1-b X b O 2-c D c (0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.05);

[0033] Li a E 1-b X b O 2-c D c (0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.05);

[0034] Li a E 2-b X b O 4-c D c (0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.05);

[0035] Li a Ni 1-b-c Co b X c D α (0.90 ≤ a ≤1.8, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.5, 0 <α ≤ 2);

[0036] Li a Ni 1-b-c Co b X c O 2-α T α(0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.05, 0 < α < 2);

[0037] Li a Ni 1-b-c Co b X c O 2-α T2(0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.05, 0 < α < 2);

[0038] Li a Ni 1-b-c Mr b X c D α (0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.05, 0 < α ≤ 2);

[0039] Li a Ni 1-b-c Mr b X c O 2-α T α (0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.05, 0 < α < 2);

[0040] Li a Ni 1-b-c Mr b X c O 2-α T2(0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.05, 0 < α < 2);

[0041] Li a Ni b HAVE BEEN c G d O2(0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.9, 0 ≤ c ≤ 0.5, 0.001 ≤ d ≤ 0.1);

[0042] Li a Ni b Co c Mr d G eO2(0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.9, 0 ≤ c ≤ 0.5, 0 ≤ d ≤0.5, 0.001 ≤ e ≤ 0.1);

[0043] Li a NiG b O2(0.90 ≤ a ≤ 1.8, 0.001 ≤ b ≤ 0.1);

[0044] Li a CoG b O2(0.90 ≤ a ≤ 1.8, 0.001 ≤ b ≤ 0.1);

[0045] Li a Mn 1-b G b O2(0.90 ≤ a ≤ 1.8, 0.001 ≤ b ≤ 0.1);

[0046] Li a Mn2G b O4(0.90 ≤ a ≤ 1.8, 0.001 ≤ b ≤ 0.1);

[0047] Li a Mn 1-g G g PO4(0.90 ≤ a ≤ 1.8, 0 ≤ g ≤ 0.5);

[0048] QO2; QS2; LiQS2;

[0049] V2O5; LiV2O5;

[0050] LiZO2;

[0051] LiNiVO4;

[0052] Li (3-f) J2(PO4)3(0 ≤ f ≤ 2);

[0053] Li (3-f) Fe2(PO4)3(0 ≤ f ≤ 2);

[0054] Li a FePO4(0.90 ≤ a ≤ 1.8).

[0055] In the above chemical formulas, A is selected from the group consisting of Ni, Co, Mn, and combinations thereof; X is selected from the group consisting of Al, Ni, Co, Mn, Cr, Fe, Mg, Sr, V, rare earth elements, and combinations thereof; D is selected from the group consisting of O, F, S, P, and combinations thereof; E is selected from the group consisting of Co, Mn, and combinations thereof; T is selected from the group consisting of F, S, P, and combinations thereof; G is selected from the group consisting of Al, Cr, Mn, Fe, Mg, La, Ce, Sr, V, and combinations thereof; Q is selected from the group consisting of Ti, Mo, Mn, and combinations thereof; Z is selected from the group consisting of Cr, V, Fe, Sc, Y, and combinations thereof; J is selected from the group consisting of V, Cr, Mn, Co, Ni, Cu, and combinations thereof.

[0056] The above-mentioned positive electrode active material may be, for example, lithium cobalt oxide (LCO), lithium nickel oxide (LNO), lithium nickel cobalt oxide (NC), lithium nickel cobalt aluminum oxide (NCA), lithium nickel cobalt manganese oxide (NCM), lithium nickel manganese oxide (NM), lithium manganese oxide (LMO), or lithium iron phosphate (LFP).

[0057] The above positive electrode active material may include a lithium nickel-based oxide represented by the following chemical formula 1, a lithium cobalt-based oxide represented by the following chemical formula 2, a lithium iron phosphate-based compound represented by the following chemical formula 3, or a combination thereof.

[0058] [Chemical Formula 1]

[0059] Li a1 Ni x1 M 1 y1 M 2 1-x1-y1 O2

[0060] In the above chemical formula 1, 0.9≤a1≤1.8, 0.3≤x1≤1, 0≤y1≤0.7, and M 1 and M2 is one or more elements independently selected from the group consisting of Al, B, Ba, Ca, Ce, Co, Cr, Cu, F, Fe, Mg, Mn, Mo, Nb, P, S, Si, Sr, Ti, V, W, and Zr.

[0061] [Chemical Formula 2]

[0062] Li a2 Co x2 M 3 1-x2 O2

[0063] In the above chemical formula 2, 0.9≤a2≤1.8, 0.6≤x2≤1, and M 3 is one or more elements selected from the group consisting of Al, B, Ba, Ca, Ce, Cr, Cu, F, Fe, Mg, Mn, Mo, Nb, P, S, Si, Sr, Ti, V, W, and Zr.

[0064] [Chemical Formula 3]

[0065] Li a3 Fe x3 M 4 (1-x3) PO4

[0066] In the above chemical formula 3, 0.9≤a3≤1.8, 0.6≤x3≤1, and M 4 is one or more elements selected from the group consisting of Al, B, Ba, Ca, Ce, Co, Cr, Cu, F, Fe, Mg, Mn, Mo, Nb, P, S, Si, Sr, Ti, V, W, and Zr.

[0067] The average particle diameter (D50) of the positive electrode active material may be 1 μm to 25 μm, for example, 3 μm to 25 μm, 5 μm to 25 μm, 5 μm to 20 μm, 8 μm to 20 μm, or 10 μm to 18 μm. A positive electrode active material having such a particle diameter range can be harmoniously mixed with other components within the positive electrode active material layer and can realize high capacity and high energy density.

[0068] The above-mentioned positive electrode active material may be in the form of a secondary particle formed by agglomeration of a plurality of primary particles, or may be in the form of a single particle. In addition, the above-mentioned positive electrode active material may be spherical or nearly spherical in shape, or may be polyhedral or irregular in shape.

[0069] Sulfide-based solid electrolyte

[0070] Sulfide-based solid electrolytes include, for example, Li2S-P2S5, Li2S-P2S5-LiX (where X is a halogen element, for example, I or Cl), Li2S-P2S5-Li2O, Li2S-P2S5-Li2O-LiI, Li2S-SiS2, Li2S-SiS2-LiI, Li2S-SiS2-LiBr, Li2S-SiS2-LiCl, Li2S-SiS2-B2S3-LiI, Li2S-SiS2-P2S5-LiI, Li2S-B2S3, Li2S-P2S5-Z. m S n (m, n are integers, Z is Ge, Zn or Ga), Li2S-GeS2, Li2S-SiS2-Li3PO4, Li2S-SiS2-Li p MO q (p, q are integers, and M is P, Si, Ge, B, Al, Ga or In), or a combination thereof.

[0071] Such sulfide-based solid electrolytes can be obtained, for example, by mixing Li2S and P2S5 in a molar ratio of 50:50 to 90:10, or 50:50 to 80:20, and optionally heat-treating them. Within the above mixing ratio range, a sulfide-based solid electrolyte having excellent ionic conductivity can be produced. Here, the ionic conductivity can be further improved by further including other components such as SiS2, GeS2, and B2S3.

[0072] Methods for mixing sulfur-containing raw materials for producing sulfide-based solid electrolytes include mechanical milling or the solution method. Mechanical milling involves placing the starting raw materials in a reactor and vigorously stirring them with a ball mill or similar device to finely atomize and mix them. Using the solution method, the starting raw materials are mixed in a solvent to obtain a solid electrolyte as a precipitate. Furthermore, heat treatment after mixing can solidify the crystals of the solid electrolyte and improve ionic conductivity. For example, a sulfide-based solid electrolyte can be produced by mixing sulfur-containing raw materials and heat-treating them twice or more, resulting in a sulfide-based solid electrolyte with high ionic conductivity and robustness.

[0073] For example, the sulfide-based solid electrolyte particles may include argyrodite-type sulfides. The argyrodite-type sulfides may include, for example, Li a M b P c S d A e (wherein a, b, c, d and e are all 0 or more and 12 or less, M is a metal other than Li or a combination of multiple metals other than Li, and A is F, Cl, Br, or I) and a specific example is Li 7-x PS 6-x A x (x is 0.2 or more and 1.8 or less, and A is F, Cl, Br, or I) can be expressed by the chemical formula. The above argyrodite-type sulfide is specifically Li3PS4, Li7P3S 11 , Li7PS6, Li6PS5Cl, Li6PS5Br, Li 5.8 PS 4.8 Cl 1.2 , Li 6.2 PS 5.2 Br 0.8 It could be the back.

[0074] Sulfide-based solid electrolyte particles containing these argyrodite-type sulfides have an ionic conductivity of 10, which is the ionic conductivity of a typical liquid electrolyte at room temperature. -4 10 inland -2 It has a high ionic conductivity approaching the S / cm range, can form a close bond between a positive electrode active material and a solid electrolyte without causing a decrease in ionic conductivity, and can further form a close interface between an electrode layer and a solid electrolyte layer. An all-solid-state battery including this can have improved battery performance, such as rate characteristics, Coulombic efficiency, and cycle life characteristics.

[0075] An argyrodite-type sulfide-based solid electrolyte can be prepared, for example, by mixing lithium sulfide, phosphorus sulfide, and optionally, a lithium halide. After mixing, a heat treatment may be performed. The heat treatment may include, for example, two or more heat treatment steps.

[0076] According to one embodiment, the average particle diameter (D50) of the sulfide-based solid electrolyte particles may be 5.0 ㎛ or less, for example, 0.1 ㎛ to 5.0 ㎛, 0.1 ㎛ to 4.0 ㎛, 0.1 ㎛ to 3.0 ㎛, 0.5 ㎛ to 2.0 ㎛, or 0.1 ㎛ to 1.5 ㎛. Alternatively, the sulfide-based solid electrolyte particles may be small particles having an average particle diameter (D50) of 0.1 ㎛ to 1.0 ㎛, or may be large particles having an average particle diameter (D50) of 1.5 ㎛ to 5.0 ㎛, depending on the location or purpose of use. The sulfide-based solid electrolyte particles having such a particle diameter range can effectively penetrate between solid particles in a battery, and have excellent contact with an electrode active material and connectivity between solid electrolyte particles. The average particle size of the sulfide-based solid electrolyte particles may be measured from a microscope image, for example, by measuring the sizes of about 20 particles in a scanning electron microscope image to obtain a particle size distribution and calculating D50 from this.

[0077] The content of the solid electrolyte in the positive electrode for the all-solid-state battery may be 0.5 wt% to 35 wt%, for example, 1 wt% to 35 wt%, 5 wt% to 30 wt%, 8 wt% to 25 wt%, or 10 wt% to 20 wt%. This is the content relative to the total weight of components in the positive electrode, and specifically, it can be said to be the content relative to the total weight of the positive electrode active material layer.

[0078] In one embodiment, the positive electrode active material layer may include 50 wt% to 99.35 wt% of the positive electrode active material, 0.5 wt% to 35 wt% of the sulfide-based solid electrolyte, 0.1 wt% to 10 wt% of the fluorine-based resin binder, and 0.05 wt% to 5 wt% of the vanadium oxide, based on 100 wt% of the positive electrode active material layer. When this content range is satisfied, the positive electrode for an all-solid-state secondary battery can implement high capacity and high ionic conductivity while maintaining high adhesiveness, and the viscosity of the positive electrode composition can be maintained at an appropriate level, thereby improving processability.

[0079] bookbinder

[0080] The binder serves to adhere the positive electrode active material particles well to each other and also to adhere the positive electrode active material well to the current collector, and representative examples thereof include, but are not limited to, polyvinyl alcohol, carboxymethyl cellulose, hydroxypropyl cellulose, diacetyl cellulose, polyvinyl chloride, carboxylated polyvinyl chloride, polyvinyl fluoride, polymers containing ethylene oxide, polyvinyl pyrrolidone, polyurethane, polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, polypropylene, styrene-butadiene rubber, acrylated styrene-butadiene rubber, epoxy resin, nylon, etc.

[0081] Challenge

[0082] The above-described positive electrode active material layer may further include a conductive material. The conductive material is used to impart conductivity to the electrode, and may include, for example, carbon-based materials such as natural graphite, artificial graphite, carbon black, acetylene black, Ketjen black, carbon fibers, and carbon nanotubes; metal-based materials containing copper, nickel, aluminum, silver, and the like in the form of metal powder or metal fibers; conductive polymers such as polyphenylene derivatives; or combinations thereof.

[0083] The conductive material may be included in an amount of 0.1 wt% to 5 wt%, or 0.1 wt% to 3 wt%, based on the total weight of each component of the positive electrode for the all-solid-state battery, or based on the total weight of the positive electrode active material layer. Within the above content range, the conductive material can improve electrical conductivity without degrading battery performance.

[0084] When the positive electrode active material layer further includes a conductive material, the positive electrode active material layer may include 45 wt% to 99.25 wt% of the positive electrode active material, 0.5 wt% to 35 wt% of the sulfide-based solid electrolyte, 0.1 wt% to 10 wt% of the fluorine-based resin binder, 0.05 wt% to 5 wt% of the vanadium oxide, and 0.1 wt% to 5 wt% of the conductive material, based on 100 wt% of the positive electrode active material layer.

[0085] Meanwhile, the positive electrode for the lithium secondary battery may further include an oxide-based inorganic solid electrolyte in addition to the above-described solid electrolyte. The oxide-based inorganic solid electrolyte may be, for example, Li 1+x Ti 2-x Al(PO4)3(LTAP)(0≤x≤4), Li 1+x+y Al x Ti 2-x Si y P 3-y O 12 (0 <x<2, 0≤y<3), BaTiO3, Pb(Zr,Ti)O3(PZT), Pb 1-x La x Zr1-y Ti y O3(PLZT)(0≤x<1, 0≤y<1), PB(Mg3Nb 2 / 3 )O3-PbTiO3(PMN-PT), HfO2, SrTiO3, SnO2, CeO2, Na2O, MgO, NiO, CaO, BaO, ZnO, ZrO2, Y2O3, Al2O3, TiO2, SiO2, lithium phosphate (Li3PO4), lithium titanium phosphate (Li x Ti y (PO4)3, 0 <x<2, 0<y<3), Li 1+x+y (Al, Ga) x (Ti, Ge) 2-x Si y P 3-y O 12 (0≤x≤1, 0≤y≤1), lithium lanthanum titanate (Li x La y TiO3, 0 <x<2, 0<y<3), Li2O, LiAlO2, Li2O-Al2O3-SiO2-P2O5-TiO2-GeO2계 세라믹스, 가넷(Garnet)계 세라믹스 Li 3+x La3M2O 12 (M= Te, Nb, or Zr; x is an integer from 1 to 10), or a combination thereof.

[0086] All-solid-state secondary battery

[0087] In one embodiment, an all-solid-state secondary battery is provided, including the aforementioned positive electrode and negative electrode and a solid electrolyte layer positioned between the positive electrode and negative electrode. The all-solid-state secondary battery may also be referred to as an all-solid-state battery or an all-solid-state lithium secondary battery.

[0088] Fig. 1 is a cross-sectional view of an all-solid-state secondary battery according to one embodiment. Referring to Fig. 1, the all-solid-state secondary battery (100) may have a structure in which an electrode assembly in which a negative electrode (400) including a negative electrode current collector (401) and a negative electrode active material layer (403), a solid electrolyte layer (300), and a positive electrode (200) including a positive electrode active material layer (203) and a positive electrode current collector (201) are laminated is housed in a case such as a pouch. The all-solid-state secondary battery (100) may further include an elastic layer (500) on the outer side of at least one of the positive electrode (200) and the negative electrode (400). Although Fig. 1 illustrates one electrode assembly including a negative electrode (400), a solid electrolyte layer (300), and a positive electrode (200), an all-solid-state battery may be manufactured by laminating two or more electrode assemblies.

[0089] cathode

[0090] An anode for an all-solid-state battery may include, for example, a current collector and a layer of anode active material positioned on the current collector. The layer of anode active material includes a cathode active material and may further include a binder, a conductive material, and / or a solid electrolyte.

[0091] The above negative active material may include a material capable of reversibly intercalating / deintercalating lithium ions, lithium metal, an alloy of lithium metal, a material capable of doping and dedoping lithium, or a transition metal oxide.

[0092] The material capable of reversibly intercalating / deintercalating the lithium ions may include a carbon-based negative electrode active material, for example, crystalline carbon, amorphous carbon, or a combination thereof. Examples of the crystalline carbon include graphite such as natural graphite or artificial graphite in an amorphous, plate-like, flake-like, spherical, or fibrous form, and examples of the amorphous carbon include soft carbon or hard carbon, mesophase pitch carbide, calcined coke, and the like.

[0093] As the above lithium metal alloy, an alloy of lithium and one or more metals selected from Na, K, Rb, Cs, Fr, Be, Mg, Ca, Sr, Si, Sb, Pb, In, Zn, Ba, Ra, Ge, Al, and Sn can be used.

[0094] As the material capable of doping and dedoping the lithium, a Si-based negative electrode active material or a Sn-based negative electrode active material can be used, and the Si-based negative electrode active material may be silicon, a silicon-carbon composite, or SiO. x (0 <x<2), Si-Q 합금(상기 Q는 알칼리 금속, 알칼리 토금속, 13족 원소, 14족 원소, 15족 원소, 16족 원소, 전이금속, 희토류 원소 및 이들의 조합으로 이루어진 군에서 선택되는 원소이며, Si은 아님), 상기 Sn계 음극 활물질로는 Sn, SnO2, Sn-R 합금(상기 R은 알칼리 금속, 알칼리 토금속, 13족 원소, 14족 원소, 15족 원소, 16족 원소, 전이금속, 희토류 원소 및 이들의 조합으로 이루어진 군에서 선택되는 원소이며, Sn은 아님) 등을 들 수 있고, 또한 이들 중 적어도 하나와 SiO2를 혼합하여 사용할 수도 있다. 상기 원소 Q 및 R로는 Mg, Ca, Sr, Ba, Ra, Sc, Y, Ti, Zr, Hf, Rf, V, Nb, Ta, Db, Cr, Mo, W, Sg, Tc, Re, Bh, Fe, Pb, Ru, Os, Hs, Rh, Ir, Pd, Pt, Cu, Ag, Au, Zn, Cd, B, Al, Ga, Sn, In, Tl, Ge, P, As, Sb, Bi, S, Se, Te, Po, 및 이들의 조합으로 이루어진 군에서 선택되는 것을 사용할 수 있다.

[0095] The silicon-carbon composite may be, for example, a silicon-carbon composite including a core comprising crystalline carbon and silicon particles and an amorphous carbon coating layer positioned on the surface of the core. The crystalline carbon may be artificial graphite, natural graphite, or a combination thereof. As the amorphous carbon precursor, coal pitch, mesophase pitch, petroleum pitch, coal oil, petroleum heavy oil, or a polymer resin such as a phenol resin, a furan resin, or a polyimide resin may be used. At this time, the content of silicon may be 10 wt% to 50 wt% with respect to the total weight of the silicon-carbon composite. In addition, the content of the crystalline carbon may be 10 wt% to 70 wt% with respect to the total weight of the silicon-carbon composite, and the content of the amorphous carbon may be 20 wt% to 40 wt% with respect to the total weight of the silicon-carbon composite. In addition, the thickness of the amorphous carbon coating layer may be 5 nm to 100 nm.

[0096] The average particle diameter (D50) of the above silicon particles may be 10 nm to 20 μm, for example, 10 nm to 500 nm. The silicon particles may exist in an oxidized form, and at this time, the atomic content ratio of Si:O in the silicon particles, which indicates the degree of oxidation, may be 99:1 to 33:67. The silicon particles may be SiO x It can be a particle, in which case SiO x In the range of x, it can be greater than 0 and less than 2. Here, the average particle diameter (D50) is measured by a particle size analyzer using laser diffraction and means the diameter of particles having a cumulative volume of 50% by volume in the particle size distribution.

[0097] The above Si-based negative electrode active material or Sn-based negative electrode active material can be used in combination with a carbon-based negative electrode active material. The mixing ratio of the Si-based negative electrode active material or Sn-based negative electrode active material and the carbon-based negative electrode active material can be 1:99 to 90:10 by weight.

[0098] The content of the negative active material in the above negative active material layer may be 95 wt% to 99 wt% with respect to the total weight of the negative active material layer.

[0099] In one embodiment, the negative electrode active material layer further includes a binder and may optionally further include a conductive material. The content of the binder in the negative electrode active material layer may be 1 wt% to 5 wt% based on the total weight of the negative electrode active material layer. In addition, when the negative electrode active material layer further includes a conductive material, the negative electrode active material layer may include 90 wt% to 98 wt% of the negative electrode active material, 1 wt% to 5 wt% of the binder, and 1 wt% to 5 wt% of the conductive material.

[0100] The above binder serves to adhere the negative active material particles well to each other and also to adhere the negative active material well to the current collector. The binder may include an insoluble binder, a water-soluble binder, or a combination thereof.

[0101] The above-described non-aqueous binder may include, for example, polyvinyl chloride, carboxylated polyvinyl chloride, polyvinyl fluoride, a polymer comprising ethylene oxide, an ethylene propylene copolymer, polystyrene, polyvinylpyrrolidone, polyurethane, polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, polypropylene, polyamideimide, polyimide, or a combination thereof.

[0102] The water-soluble binder may be a rubber-based binder or a polymer resin binder. The rubber-based binder may be selected from styrene-butadiene rubber, acrylated styrene-butadiene rubber, acrylonitrile-butadiene rubber, acrylic rubber, butyl rubber, fluororubber, and combinations thereof. The polymer resin binder may be selected from polyethylene oxide, polyvinylpyrrolidone, polyepichlorohydrin, polyphosphazene, polyacrylonitrile, ethylene propylene diene copolymer, polyvinylpyridine, chlorosulfonated polyethylene, latex, polyester resin, acrylic resin, phenol resin, epoxy resin, polyvinyl alcohol, and combinations thereof.

[0103] When a water-soluble binder is used as the negative electrode binder, a thickener capable of imparting viscosity may be used together, and the thickener may include, for example, a cellulose-based compound. The cellulose-based compound may include carboxymethyl cellulose, hydroxypropylmethyl cellulose, methyl cellulose, an alkali metal salt thereof, or a combination thereof. Na, K, or Li may be used as the alkali metal. The amount of the thickener used may be 0.1 to 3 parts by weight based on 100 parts by weight of the negative electrode active material.

[0104] The conductive material is used to provide conductivity to the electrode, and may include, for example, carbon-based materials such as natural graphite, artificial graphite, carbon black, acetylene black, Ketjen black, carbon fibers, and carbon nanotubes; metal-based materials in the form of metal powder or metal fibers, including copper, nickel, aluminum, and silver; conductive polymers such as polyphenylene derivatives; or mixtures thereof.

[0105] The negative electrode current collector may be selected from copper foil, nickel foil, stainless steel foil, titanium foil, nickel foam, copper foam, a polymer substrate coated with a conductive metal, and a combination thereof.

[0106] As another example, the negative electrode for the all-solid-state battery may be a precipitation-type negative electrode. The precipitation-type negative electrode refers to a negative electrode that does not include a negative electrode active material when the battery is assembled, but in which lithium metal or the like is precipitated when the battery is charged, and this acts as a negative electrode active material.

[0107] FIG. 2 is a schematic cross-sectional view of an all-solid-state secondary battery including a precipitation-type negative electrode according to one embodiment. Referring to FIG. 2, the precipitation-type negative electrode (400') may include a current collector (401) and a negative electrode coating layer (405) positioned on the current collector. An all-solid-state battery including such a precipitation-type negative electrode (400') starts initial charging in a state in which no negative electrode active material is present, and upon charging, a high-density lithium metal or the like is precipitated between the current collector (401) and the negative electrode coating layer (405) to form a lithium metal layer (404), which may function as a negative electrode active material. Accordingly, in an all-solid-state battery that has been charged at least once, the precipitation-type negative electrode (400') may include a current collector (401), a lithium metal layer (404) positioned on the current collector, and a negative electrode coating layer (405) positioned on the metal layer. The above lithium metal layer (404) refers to a layer in which lithium metal, etc. is precipitated during the charging process of the battery, and may be referred to as a metal layer or a negative electrode active material layer.

[0108] The above cathode coating layer (405) may include a metal, a carbon material, or a combination thereof that acts as a catalyst.

[0109] The metal may include, for example, gold, platinum, palladium, silicon, silver, aluminum, bismuth, tin, zinc, or a combination thereof, and may be composed of one type of these or may be composed of an alloy of several types. When the metal is present in the form of particles, the average particle diameter (D50) thereof may be about 4 μm or less, for example, 10 nm to 4 μm.

[0110] The carbon material may be, for example, crystalline carbon, amorphous carbon, or a combination thereof. The crystalline carbon may be, for example, natural graphite, artificial graphite, mesophase carbon microbeads, or a combination thereof. The amorphous carbon may be, for example, carbon black, activated carbon, acetylene black, Denka black, Ketjen black, or a combination thereof.

[0111] When the above-described negative electrode coating layer (405) includes both the metal and the carbon material, the mixing ratio of the metal and the carbon material may be, for example, a weight ratio of 1:10 to 2:1. In this case, the precipitation of lithium metal can be effectively promoted and the characteristics of the all-solid-state battery can be improved. The above-described negative electrode coating layer (405) may include, for example, a carbon material supported with a catalytic metal, or may include a mixture of metal particles and carbon material particles.

[0112] The above cathode coating layer (405) may include, for example, the metal and amorphous carbon, in which case it can effectively promote the precipitation of lithium metal.

[0113] The above cathode coating layer (405) may further include a binder, and the binder may be a conductive binder. In addition, the above cathode coating layer (405) may further include general additives such as fillers, dispersants, and ionic conductive agents.

[0114] The thickness of the cathode coating layer (405) may be, for example, 100 nm to 20 ㎛, or 500 nm to 10 ㎛, or 1 ㎛ to 5 ㎛.

[0115] The above-described precipitated negative electrode (400') may further include, for example, a thin film on the surface of the current collector, i.e., between the current collector and the negative electrode coating layer. The thin film may include an element capable of forming an alloy with lithium. The element capable of forming an alloy with lithium may be, for example, gold, silver, zinc, tin, indium, silicon, aluminum, bismuth, etc., and may be composed of one type thereof or may be composed of multiple types of alloys. The thin film may further flatten the precipitated form of the lithium metal layer (404) and further improve the characteristics of the all-solid-state battery. The thin film may be formed by, for example, a vacuum deposition method, a sputtering method, a plating method, etc. The thickness of the thin film may be, for example, 1 nm to 500 nm.

[0116] solid electrolyte layer

[0117] The solid electrolyte layer (300) may include a sulfide-based solid electrolyte, an oxide-based solid electrolyte, etc. The specific details of the sulfide-based solid electrolyte and the oxide-based solid electrolyte are as described above.

[0118] In one example, the solid electrolyte included in the positive electrode (200) and the solid electrolyte included in the solid electrolyte layer (300) may include the same compound or different compounds. For example, when both the positive electrode (200) and the solid electrolyte layer (300) include an argyrodite-type sulfide-based solid electrolyte, the overall performance of the all-solid-state secondary battery may be improved. In addition, for example, when both the positive electrode (200) and the solid electrolyte layer (300) include the above-described coated solid electrolyte, the all-solid-state secondary battery may implement high capacity and high energy density while implementing excellent initial efficiency and lifespan characteristics.

[0119] Meanwhile, the average particle diameter (D50) of the solid electrolyte included in the positive electrode (200) may be smaller than the average particle diameter (D50) of the solid electrolyte included in the solid electrolyte layer (300). In this case, the energy density of the all-solid-state battery can be maximized while increasing the mobility of lithium ions, thereby improving the overall performance. For example, the average particle diameter (D50) of the solid electrolyte included in the positive electrode (200) may be 0.1 ㎛ to 1.0 ㎛, or 0.1 ㎛ to 0.8 ㎛, and the average particle diameter (D50) of the solid electrolyte included in the solid electrolyte layer (300) may be 1.5 ㎛ to 5.0 ㎛, or 2.0 ㎛ to 4.0 ㎛, or 2.5 ㎛ to 3.5 ㎛. When this particle size range is satisfied, the energy density of the all-solid-state secondary battery can be maximized while lithium ion transport is facilitated, resistance is suppressed, and the overall performance of the all-solid-state secondary battery can be improved. Here, the average particle diameter (D50) of the solid electrolyte can be measured using a particle size analyzer using laser diffraction. Alternatively, the particle size can be measured by selecting 20 or so random particles from a microscope image such as a scanning electron microscope, obtaining a particle size distribution, and calculating the D50 value from this.

[0120] The above solid electrolyte layer may further include a binder in addition to the solid electrolyte. At this time, the binder may be styrene butadiene rubber, polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, an acrylate polymer, or a combination thereof, but is not limited thereto, and any binder used in the relevant technical field may be used. The acrylate polymer may be, for example, butyl acrylate, polyacrylate, polymethacrylate, or a combination thereof.

[0121] The above solid electrolyte layer can be formed by adding a solid electrolyte to a binder solution, coating the same on a base film, and drying the same. The solvent of the binder solution may be isobutyryl isobutyrate, xylene, toluene, benzene, hexane, or a combination thereof. Since the solid electrolyte layer formation process is widely known in the art, a detailed description thereof will be omitted.

[0122] The thickness of the solid electrolyte layer may be, for example, 10 ㎛ to 150 ㎛.

[0123] The above solid electrolyte layer may further include an alkali metal salt, and / or an ionic liquid, and / or a conductive polymer.

[0124] The above alkali metal salt may be, for example, a lithium salt. The content of the lithium salt in the solid electrolyte layer may be 1 M or more, for example, 1 M to 4 M. In this case, the lithium salt may improve ion conductivity by enhancing the lithium ion mobility of the solid electrolyte layer.

[0125] The above lithium salts include, for example, LiSCN, LiN(CN)2, Li(CF3SO2)3C, LiC4F9SO3, LiN(SO2CF2CF3)2, LiCl, LiF, LiBr, LiI, LiB(C2O4)2, LiBF4, LiBF3(C2F5), lithium bis(oxalato)borate (LiBOB), lithium oxalyldifluoroborate (LIODFB), lithium difluoro(oxalato)borate (LiDFOB), lithium bis(trifluoro methanesulfonyl)imide (LiTFSI, LiN(SO2CF3)2), lithium bis(fluorosulfonyl)imide (LiFSI, It may include LiN(SO2F)2), LiCF3SO3, LiAsF6, LiSbF6, LiClO4 or mixtures thereof.

[0126] In addition, the lithium salt may be an imide-based one, and for example, the imide-based lithium salt may include lithium bis(trifluoro methanesulfonyl)imide (LiTFSI, LiN(SO2CF3)2), lithium bis(fluorosulfonyl)imide (LiFSI, LiN(SO2F)2). The lithium salt may maintain or improve ionic conductivity by appropriately maintaining chemical reactivity with an ionic liquid.

[0127] The above ionic liquid has a melting point below room temperature and is a salt or room-temperature molten salt that is liquid at room temperature and consists only of ions.

[0128] The above ionic liquid may be a compound including a) one or more cations selected from ammonium-based, pyrrolidinium-based, pyridinium-based, pyrimidinium-based, imidazolium-based, piperidinium-based, pyrazolium-based, oxazolium-based, pyridazinium-based, phosphonium-based, sulfonium-based, triazolium-based, and mixtures thereof, and b) one or more anions selected from BF4-, PF6-, AsF6-, SbF6-, AlCl4-, HSO4-, ClO4-, CH3SO3-, CF3CO2-, Cl-, Br-, I-, BF4-, SO4-, CF3SO3-, (FSO2)2N-, (C2F5SO2)2N-, (C2F5SO2)(CF3SO2)N-, and (CF3SO2)2N-.

[0129] The ionic liquid may be at least one selected from the group consisting of, for example, N-methyl-N-propylpyrrolidinium bis(trifluoromethanesulfonyl)imide, N-butyl-N-methylpyrrolidinium bis(3-trifluoromethylsulfonyl)imide, 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)amide, and 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)amide.

[0130] In the above solid electrolyte layer, the weight ratio of the solid electrolyte and the ionic liquid may be 0.1:99.9 to 90:10, for example, 10:90 to 90:10, 20:80 to 90:10, 30:70 to 90:10, 40:60 to 90:10, or 50:50 to 90:10. A solid electrolyte layer satisfying the above range can maintain or improve ionic conductivity by improving the electrochemical contact area with the electrode. Accordingly, the energy density, discharge capacity, rate characteristics, etc. of the all-solid-state battery can be improved.

[0131] The above-mentioned all-solid-state battery may be a unit battery having a structure of positive electrode / solid electrolyte layer / negative electrode, a bi-cell having a structure of positive electrode / solid electrolyte layer / negative electrode / solid electrolyte layer / positive electrode, or a laminated battery in which the structure of the unit battery is repeated.

[0132] The shape of the above-mentioned all-solid-state battery is not particularly limited, and may be, for example, coin-shaped, button-shaped, sheet-shaped, stacked, cylindrical, flat, etc. In addition, the above-mentioned all-solid-state battery can be applied to large-scale batteries used in electric vehicles, etc. For example, the above-mentioned all-solid-state battery can be used in hybrid vehicles such as plug-in hybrid electric vehicles (PHEVs). In addition, it can be used in fields requiring large amounts of power storage, and for example, it can be used in electric bicycles or power tools.

[0133] Hereinafter, with reference to FIGS. 3 to 5, a method for manufacturing an all-solid-state secondary battery according to the first embodiment will be described.

[0134] FIG. 3 is a longitudinal cross-sectional view of forming a positive electrode on a first laminate in which a first solid electrolyte layer is laminated on a negative electrode in a method for manufacturing an all-solid-state secondary battery according to a first embodiment of the present invention, FIG. 4 is a longitudinal cross-sectional view of forming a gasket on the first laminate of FIG. 3, and FIG. 5 is a longitudinal cross-sectional view of forming a finishing part between the positive electrode and the gasket of the first laminate of FIG. 4.

[0135] Referring to FIGS. 3 to 5, the method for manufacturing an all-solid-state secondary battery according to the first embodiment includes a first step (ST1), a second step (ST2), a third step (ST3), and a fourth step (ST4).

[0136] An all-solid-state secondary battery (1) manufactured by the manufacturing method of the first embodiment includes a negative electrode (10), a solid electrolyte layer (20), and a positive electrode (30), and includes a gasket (40) for compensating for the thickness difference between the negative electrode (10) and the positive electrode (30) and for an insulating function. It is necessary to reduce the gap (G) established between the gasket (40) and the positive electrode (30) in the laminated structure of the all-solid-state secondary battery (1).

[0137] Referring to FIG. 3, the first step (ST1) forms a first laminate (LB1) by laminating a solid electrolyte layer (20) on a cathode (10). For convenience, the cathode (10) is referred to as the first cathode (10) and the solid electrolyte layer (20) is referred to as the first solid electrolyte layer (20). The second step (ST2) laminates a cathode (30) on the first solid electrolyte layer (20) of the first laminate (LB1).

[0138] In the third step (ST3), a gasket (40) is laminated on the first solid electrolyte layer (20) and spaced apart from the positive electrode (30). Accordingly, a gap (G) is established between the positive electrode (30) and the gasket (40). The gap (G) between the positive electrode (30) and the gasket (40) may be larger in the scale-up process of the all-solid-state secondary battery (1) due to errors resulting from equipment tolerances and manual processing.

[0139] Step 4 (ST4) forms a closing portion (50) in the gap (G). The closing portion (50) compensates for the thickness difference between the cathode (10) and the anode (30) by the gasket (40). At the same time, the closing portion (50) fills the gap (G) between the gasket (40) and the anode (30).

[0140] Fig. 6 is a plan view of an all-solid-state secondary battery according to a first embodiment of the present invention. Referring to Fig. 6, in an all-solid-state secondary battery (1) according to the first embodiment, a positive electrode substrate tab (31) of a positive electrode (30) and a negative electrode substrate tab (11) of a negative electrode (10) are pulled out to opposite ends of each other.

[0141] The anode (30) is formed with an area smaller than the inner space of the gasket (40) and is placed in the inner space of the gasket (40). Accordingly, the connection portion (32) of the anode (30) and the anode substrate tab (31) is placed in the inner space of the gasket (40), and the anode substrate tab (31) is pulled outward while being supported by the gasket (40) in the inner space.

[0142] The cathode (10) is formed with an area larger than the inner space of the gasket (40) and the outer portion is placed on the gasket (40). Accordingly, the connection portion (12) of the cathode (10) and the cathode substrate tab (11) is placed on the gasket (40), and the cathode substrate tab (11) is pulled outward from the gasket (40).

[0143] Step 4 (ST4) can form the closing portion (50) with the positive electrode active material of the positive electrode (30). At this time, the positive electrode active material powder has a small particle size, so it can fill the gap (G) more finely. The positive electrode active material powder can contain a small amount of binder. The positive electrode active material filled in the gap (G) increases the capacity of the battery.

[0144] Step 4 (ST4) may form the finishing portion (50) by powder coating, slurry spray coating, or slurry coating. For example, the finishing portion (50) may be formed by applying positive electrode active material powder to the gap (G), spray coating positive electrode active material slurry, or applying positive electrode active material slurry.

[0145] In addition, the fourth step (ST4) can form the finishing portion (50) with the solid electrolyte of the first solid electrolyte layer (20). At this time, since the solid electrolyte powder has a small particle size, it can fill the gap (G) more finely. The solid electrolyte powder can contain a small amount of binder. For example, the finishing portion (50) can be formed by applying the solid electrolyte powder to the gap (G), spray coating the solid electrolyte slurry, or applying the solid electrolyte slurry.

[0146] Step 4 (ST4) further includes a step of pressurizing the positive electrode (30), the gasket (40), and the closing portion (50) to further fill the gap (G) with the closing portion (50). As an example, the warm isostatic pressing (WIP) process fills the gap (G) of the positive electrode (30) and the gasket (40) with positive electrode active material powder or solid electrolyte powder to form the closing portion (50).

[0147] The gasket (40) and the closing portion (50) enable the warm isostatic pressing (WIP) process to proceed smoothly, and the difference in thickness between the anode (30) and the gasket (40) on the first solid electrolyte (20) is eliminated, thereby preventing the occurrence of cracks at the end of the anode (30).

[0148] The gasket (40) and the closing portion (50) are configured to apply isostatic pressing even on the positive and negative electrode substrate tabs (31, 11) and the connecting portions (32, 12) located on the closing portion (50) during warm isostatic pressing (WIP). Accordingly, cracks and side reactions are prevented on the positive and negative electrode substrate tabs (31, 11) and the connecting portions (32, 12) located on the gap (G), thereby preventing initial short circuiting of the cell.

[0149] Hereinafter, a second embodiment of the present invention will be described. Compared to the first embodiment, descriptions of identical components will be omitted, and additional components will be described.

[0150] FIG. 7 is a cross-sectional view illustrating a method for manufacturing an all-solid-state secondary battery according to a second embodiment of the present invention, in which a second laminate is laminated on the monocell of FIG. 5 to form a bi-cell. Referring to FIG. 7, the method for manufacturing an all-solid-state secondary battery according to the second embodiment further includes a fifth step (ST5) and a sixth step (ST6).

[0151] Step 5 (ST5) forms a second laminate (LB2) by laminating a second solid electrolyte layer (220) on a second cathode (210). Step 5 (ST5) is similar to step 1 (ST1) in which a solid electrolyte layer (20) is laminated on a cathode (10) to form a first laminate (LB1).

[0152] Step 6 (ST6) laminates the second solid electrolyte layer (220) of the second laminate (LB2) on the anode (30), the finishing part (50), and the gasket (40). Step 6 (ST6) pressurizes the second laminate (LB2) to pressurize the anode (30), the gasket (40), and the finishing part (50) to further fill the gap (G) with the finishing part (50).

[0153] The gasket (40) and the closing portion (50) eliminate the difference in thickness between the anode (30) and the gasket (40) between the first laminate (LB1) and the second laminate (LB2), thereby preventing cracks from occurring at the end of the anode (30).

[0154] The gasket (40) and the closing portion (50) positioned between the first laminate (LB1) and the second laminate (LB2) enable the work-in-process (WIP) process to proceed smoothly. Accordingly, cracks and side reactions are prevented on the positive and negative electrode substrate tabs (31, 11) and the connecting portions (32, 12) positioned corresponding to the gap (G), thereby preventing the initial short circuit of the cell.

[0155] The above description is only one embodiment for implementing the all-solid-state secondary battery according to the present disclosure, and the present disclosure is not limited to the above-described embodiment, and as claimed in the following claims, it will be understood that the technical spirit of the present disclosure encompasses a range in which various modifications can be implemented without departing from the gist of the present disclosure by anyone having ordinary skill in the art to which the invention pertains.

[0156] (Explanation of symbols)

[0157] 1, 2: All-solid-state secondary battery 10: (First) negative electrode

[0158] 11, 31: Positive electrode tab 12, 32: Connection

[0159] 20: (First) solid electrolyte layer 30: anode

[0160] 40: Gasket 50: End

[0161] 210: Second cathode 220: Second solid electrolyte layer

[0162] G: Gap LB1, LB2: First laminate

Claims

1. A first step of forming a first laminate by laminating a first solid electrolyte layer on a first cathode; A second step of laminating an anode on the first solid electrolyte layer of the first laminate; A third step of laminating a gasket on the first solid electrolyte layer and spaced apart from the anode; and A fourth step of forming a closing part in the gap set between the above anode and the above gasket. A method for manufacturing an all-solid-state secondary battery comprising:

2. In paragraph 1, The above 4th step is A method for manufacturing an all-solid-state secondary battery, wherein the above-mentioned closing part is formed with a positive electrode active material of the positive electrode.

3. In paragraph 1, The above 4th step is A method for manufacturing an all-solid-state secondary battery, wherein the above-mentioned closing part is formed with a solid electrolyte of the first solid electrolyte layer.

4. In paragraph 1, The above 4th step is A method for manufacturing an all-solid-state secondary battery, wherein the above-mentioned finishing part is formed by any one of powder coating, slurry spray coating, and slurry coating.

5. In paragraph 1, The above 4th step is A method for manufacturing an all-solid-state secondary battery further comprising the step of pressurizing the positive electrode, the gasket, and the closing portion to fill the gap with the closing portion.

6. In paragraph 1, Step 5 of forming a second laminate by laminating a second solid electrolyte layer on the second cathode; and A method for manufacturing an all-solid-state secondary battery further comprising a sixth step of laminating a second solid electrolyte layer of the second laminate on the positive electrode, the finishing part, and the gasket.

7. In paragraph 6, The above 6th step is By pressurizing the above second laminated body A method for manufacturing an all-solid-state secondary battery further comprising the step of pressurizing the positive electrode, the gasket, and the closing portion to fill the gap with the closing portion.

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