All-solid rechargeable battery, and manufacturing method and device thereof

Abstract

An all-solid rechargeable battery, and a manufacturing method and device thereof are provided. The all-solid rechargeable battery according to one embodiment comprises: a band-shaped negative electrode; a first solid electrolyte layer and a second solid electrolyte layer, each provided on one of the two sides of the negative electrode; a first positive electrode stacked on the first solid electrolyte layer; and a second positive electrode stacked on the second solid electrolyte layer and spaced apart from the first positive electrode in the longitudinal direction of the negative electrode, wherein the negative electrode is bent and stacked in a zigzag manner, and the first positive electrode and the second positive electrode are alternately arranged between the bent and stacked portions.

Description

All-solid-state secondary battery, and manufacturing method and device thereof

[0001] The present disclosure relates to an all-solid-state secondary battery, and a manufacturing method and device therefor.

[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 an all-solid-state secondary battery that simplifies the assembly process, thereby reducing assembly process costs and improving safety. One embodiment provides a method for manufacturing an all-solid-state secondary battery that simplifies the assembly process, thereby reducing assembly process costs and improving safety. Another embodiment provides a manufacturing device for an all-solid-state secondary battery that simplifies the assembly process, thereby reducing assembly process costs and improving safety.

[0007] According to one embodiment, an all-solid-state secondary battery includes a band-shaped negative electrode, a first solid electrolyte layer and a second solid electrolyte layer respectively provided on both sides of the negative electrode, a first positive electrode laminated on the first solid electrolyte layer, and a second positive electrode laminated on the second solid electrolyte layer and spaced apart from the first positive electrode in the longitudinal direction of the negative electrode, wherein the negative electrode is folded and laminated in a zigzag manner, and the first positive electrode and the second positive electrode are alternately arranged between the folded and laminated layers.

[0008] Each of the first positive electrode and the second positive electrode may include a positive electrode substrate, and a first positive electrode active material layer and a second positive electrode active material layer formed on both sides of the positive electrode substrate.

[0009] The above negative electrode includes a functional layer formed on both sides of the negative electrode material, and each of the first solid electrolyte layer and the second solid electrolyte layer can be formed on each functional layer on both sides.

[0010] The first solid electrolyte layer and the second solid electrolyte layer can alternately correspond to the side end of the first positive electrode and the side end of the second positive electrode, respectively.

[0011] The above functional layer can be formed as a coating layer of a polymer or ceramic material on the above cathode substrate.

[0012] The above functional layer can be formed by bonding a separator to the above negative electrode material.

[0013] The above negative electrode is formed of lithium metal, and each of the first solid electrolyte layer and the second solid electrolyte layer can be formed on lithium metal on both sides.

[0014] The above negative electrode includes a metal pattern formed on both sides of the negative electrode material, and each of the first solid electrolyte layer and the second solid electrolyte layer can be formed on each metal pattern on both sides.

[0015] According to one embodiment of the present invention, an all-solid-state secondary battery manufacturing device includes a band-shaped negative electrode, a first solid electrolyte layer and a second solid electrolyte layer respectively provided on both sides of the negative electrode, a first positive electrode laminated on the first solid electrolyte layer, and a second positive electrode laminated on the second solid electrolyte layer and spaced apart from the first positive electrode in the longitudinal direction of the negative electrode, wherein the negative electrode is folded and laminated in a zigzag manner, and the first positive electrode and the second positive electrode are alternately arranged between the folded and laminated portions to form a laminate, a pair of lamination guides formed to support a lower surface and a side surface of the laminate and arranged oppositely on both sides in a zigzag width direction, an actuator connected to the lamination guide to control movement of the lamination guide in the width direction, and a high-temperature press for pressing the laminate supported by the lamination guide.

[0016] The above-mentioned stacking guide may include a lower plate corresponding to the lower surface of the stack, a front plate and a rear plate extending upward from the lower plate to support the front and rear sides of the stack at the adjacent side of the stack, and a side plate extending upward from the lower plate to support the side surfaces of the stack at the distal side of the stack.

[0017] The above laminated body forming unit laminates a first positive electrode on a first solid electrolyte layer provided on one side of the negative electrode along which the negative electrode in the form of a belt advances, and laminates a second positive electrode on a second solid electrolyte layer spaced apart from the first positive electrode in the longitudinal direction of the negative electrode, and can pressurize the first and second solid electrolyte layers with an upper roll and a lower roll.

[0018] The above laminate forming unit includes an upper roll for supplying the first positive electrode by attaching it to the upper roll, and a lower roll for supplying the second positive electrode by attaching it to the lower roll and spaced apart from the first positive electrode in the longitudinal direction of the negative electrode, and the first positive electrode is laminated on a first solid electrolyte layer provided on one surface of the negative electrode along which the band-shaped negative electrode advances, and the second positive electrode is laminated on a second solid electrolyte layer spaced apart from the first positive electrode in the longitudinal direction of the negative electrode, and can be pressed by the upper roll and the lower roll.

[0019] The above laminate forming unit can supply the first positive electrode by attaching it to a first plate so that the first positive electrode is laminated on a first solid electrolyte layer provided on one side of the negative electrode through which the negative electrode in the band advances, and pressurize and attach the first positive electrode to one side of the negative electrode by applying pressure with a first roll, and supply the second positive electrode by attaching it to a second plate so that the second positive electrode is laminated on the second solid electrolyte layer spaced apart from the first positive electrode in the longitudinal direction of the negative electrode, and pressurize and attach the second positive electrode to the other side of the negative electrode by applying pressure with a second roll.

[0020] The above laminate forming unit may be supplied by attaching the first positive electrode to a first plate so that the first positive electrode is laminated on a first solid electrolyte layer provided on one side of the negative electrode through which the band-shaped negative electrode advances, and pressurizing and attaching the first positive electrode to one side of the negative electrode by applying pressure with a first press, and supplying the second positive electrode by attaching the second positive electrode to a second plate so that the second positive electrode is laminated on the second solid electrolyte layer spaced apart from the first positive electrode in the longitudinal direction of the negative electrode, and pressurizing and attaching the second positive electrode to the other side of the negative electrode by applying pressure with a second press.

[0021] The above laminate forming unit supplies the first positive electrode between the left roll and the first solid electrolyte layer so as to laminate the first positive electrode on the first solid electrolyte layer provided on one side of the negative electrode in which the negative electrode on the belt advances upward, and supplies the second positive electrode between the right roll and the second solid electrolyte layer so as to laminate the second positive electrode on the second solid electrolyte layer spaced apart from the first positive electrode in the longitudinal direction of the negative electrode, thereby applying pressure with the left roll and the right roll.

[0022] The above laminate forming unit supplies the first positive electrode between the left roll and the first solid electrolyte layer so as to laminate the first positive electrode on the first solid electrolyte layer provided on one side of the negative electrode in which the negative electrode on the belt advances downward, and supplies the second positive electrode between the right roll and the second solid electrolyte layer so as to laminate the second positive electrode on the second solid electrolyte layer spaced apart from the first positive electrode in the longitudinal direction of the negative electrode, thereby applying pressure with the left roll and the right roll.

[0023] According to one embodiment of the present invention, a method for manufacturing an all-solid-state secondary battery comprises: a band-shaped negative electrode; a first solid electrolyte layer and a second solid electrolyte layer respectively provided on both sides of the negative electrode; a first positive electrode laminated on the first solid electrolyte layer; and a second positive electrode laminated on the second solid electrolyte layer and spaced apart from the first positive electrode in the longitudinal direction of the negative electrode; a first step of forming a laminate by folding and laminating the negative electrode in a zigzag shape and alternately arranging the first positive electrode and the second positive electrode between the folded and laminated shapes; a second step of supporting the lower surface and the side surface of the laminate by a pair of lamination guides that are arranged oppositely on both sides of the zigzag width direction and are advanced by an actuator; a third step of pressing the laminate supported by the lamination guides by a high-temperature press; and a third step of removing the laminate by retracting the lamination guides that support the lower surface and the side surface of the laminate after the pressing is completed by the actuator. Includes step 4.

[0024] The first step may include an 11th step of laminating a first positive electrode on a first solid electrolyte layer provided on one side of the negative electrode through which the negative electrode on the belt advances, a 12th step of laminating a second positive electrode on a second solid electrolyte layer spaced apart from the first positive electrode in the longitudinal direction of the negative electrode, and a 13th step of pressing the first positive electrode, the negative electrode, and the second positive electrode with an upper roll and a lower roll.

[0025] The first step may include an 11th step of supplying the first positive electrode by attaching it to an upper roll so as to laminate the first positive electrode on a first solid electrolyte layer provided on one side of the negative electrode on which the negative electrode on the belt advances, a 12th step of supplying the second positive electrode by attaching it to a lower roll so as to laminate the second positive electrode on the second solid electrolyte layer spaced apart from the first positive electrode in the longitudinal direction of the negative electrode, and a 13th step of pressing the first positive electrode, the negative electrode, and the second positive electrode with the upper roll and the lower roll.

[0026] The first step may include an 11th step of supplying the first positive electrode by attaching it to a first plate so that the first positive electrode is laminated on a first solid electrolyte layer provided on one side of the negative electrode along which the negative electrode on the band advances, a 12th step of pressurizing and attaching the first positive electrode to one side of the negative electrode by applying pressure between the first plate and a first roll, a 13th step of supplying the second positive electrode by attaching it to a second plate so that the second positive electrode is laminated on the second solid electrolyte layer spaced apart from the first positive electrode in the longitudinal direction of the negative electrode, and a 14th step of pressurizing and attaching the second positive electrode to the other side of the negative electrode by applying pressure between the second plate and a second roll.

[0027] The first step may include an 11th step of supplying the first positive electrode by attaching it to a first plate so that the first positive electrode is laminated on a first solid electrolyte layer provided on one side of the negative electrode along which the negative electrode on the band advances, a 12th step of pressurizing and attaching the first positive electrode to one side of the negative electrode by applying pressure to the first plate and a first press, a 13th step of supplying the second positive electrode by attaching it to a second plate so that the second positive electrode is laminated on the second solid electrolyte layer spaced apart from the first positive electrode in the longitudinal direction of the negative electrode, and a 14th step of pressurizing and attaching the second positive electrode to the other side of the negative electrode by applying pressure to the second plate and a second press.

[0028] The first step may include an 11th step of supplying the first positive electrode between the left roll and the first solid electrolyte layer so as to laminate the first positive electrode on the first solid electrolyte layer provided on one side of the negative electrode in which the negative electrode on the belt advances upward, a 12th step of supplying the second positive electrode between the right roll and the second solid electrolyte layer so as to laminate the second positive electrode on the second solid electrolyte layer spaced apart from the first positive electrode in the longitudinal direction of the negative electrode, and a 13th step of pressurizing the first positive electrode, the negative electrode, and the second positive electrode with the left roll and the right roll.

[0029] The first step may include an 11th step of supplying the first positive electrode between the left roll and the first solid electrolyte layer so as to laminate the first positive electrode on the first solid electrolyte layer provided on one side of the negative electrode in which the negative electrode on the belt advances downward, a 12th step of supplying the second positive electrode between the right roll and the second solid electrolyte layer so as to laminate the second positive electrode on the second solid electrolyte layer spaced apart from the first positive electrode in the longitudinal direction of the negative electrode, and a 13th step of pressurizing the first positive electrode, the negative electrode, and the second positive electrode with the left roll and the right roll.

[0030] In one embodiment, first and second solid electrolyte layers are provided on both sides of a negative electrode, respectively, and first and second positive electrodes are laminated on the first and second solid electrolyte layers, respectively, so that the negative electrodes are folded and laminated in a zigzag pattern so that the first and second positive electrodes are alternately arranged between the folded and laminated layers, thereby simplifying the assembly process of an all-solid-state secondary battery. Accordingly, one embodiment can reduce the cost associated with the assembly process of an all-solid-state secondary battery and improve the safety of the all-solid-state secondary battery.

[0031] Figure 1 is a cross-sectional view showing an all-solid-state secondary battery according to one embodiment.

[0032] 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.

[0033] Figure 3 is a cross-sectional view of an all-solid-state secondary battery according to a first embodiment of the present invention.

[0034] FIG. 4 is a cross-sectional view of a state before zigzag laminating a negative electrode, a first solid electrolyte layer, a second solid electrolyte layer, a first positive electrode, and a second positive electrode to manufacture the all-solid-state secondary battery of FIG. 3.

[0035] Figure 5 is a cross-sectional view of a unit cell formed of a negative electrode, a solid electrolyte layer, and a positive electrode in Figure 4.

[0036] FIG. 6 is a cross-sectional view of a unit cell formed of a negative electrode, a solid electrolyte layer, and a positive electrode in an all-solid-state secondary battery according to a second embodiment of the present invention.

[0037] FIG. 7 is a cross-sectional view of a unit cell formed of a negative electrode, a solid electrolyte layer, and a positive electrode in an all-solid-state secondary battery according to a third embodiment of the present invention.

[0038] FIG. 8 is a cross-sectional view illustrating a step of forming a laminate in a manufacturing method of manufacturing an all-solid-state secondary battery using an all-solid-state secondary battery manufacturing device according to one embodiment of the present invention.

[0039] Fig. 9 is a perspective view of a stacking guide applied to the all-solid-state secondary battery manufacturing device of Fig. 8.

[0040] Fig. 10 is a cross-sectional view of an all-solid-state secondary battery being removed during a manufacturing method using the all-solid-state secondary battery manufacturing device of Fig. 8.

[0041] FIG. 11 is a perspective view of a first embodiment of a manufacturing method for manufacturing an all-solid-state secondary battery using an all-solid-state secondary battery manufacturing apparatus according to one embodiment of the present invention, wherein a laminate is formed.

[0042] FIG. 12 is a perspective view of a second embodiment of a manufacturing method for manufacturing an all-solid-state secondary battery using an all-solid-state secondary battery manufacturing apparatus according to one embodiment of the present invention, wherein a laminate is formed.

[0043] FIG. 13 is a side view of a third embodiment of a manufacturing method for manufacturing an all-solid-state secondary battery using an all-solid-state secondary battery manufacturing apparatus according to one embodiment of the present invention, wherein a laminate is formed.

[0044] FIG. 14 is a side view of a fourth embodiment of a manufacturing method for manufacturing an all-solid-state secondary battery using an all-solid-state secondary battery manufacturing apparatus according to one embodiment of the present invention, wherein a laminate is formed.

[0045] FIG. 15 is a side view of a fifth embodiment of a manufacturing method for manufacturing an all-solid-state secondary battery using an all-solid-state secondary battery manufacturing apparatus according to one embodiment of the present invention, wherein a laminate is formed.

[0046] FIG. 16 is a side view of a sixth embodiment of a manufacturing method for manufacturing an all-solid-state secondary battery using an all-solid-state secondary battery manufacturing apparatus according to one embodiment of the present invention, wherein a laminate is formed.

[0047] Figure 17 is a flowchart of a method for manufacturing an all-solid-state secondary battery according to one embodiment of the present invention.

[0048] 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.

[0049] 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.

[0050] 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.

[0051] 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.

[0052] Cathode for all-solid-state secondary batteries

[0053] 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.

[0054] 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.

[0055] positive electrode active material

[0056] 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.

[0057] Li a A 1-b X b D2(0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.5);

[0058] 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);

[0059] 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);

[0060] 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);

[0061] 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);

[0062] 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);

[0063] 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);

[0064] 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);

[0065] 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);

[0066] 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);

[0067] 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);

[0068] 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);

[0069] Li a NiG b O2(0.90 ≤ a ≤ 1.8, 0.001 ≤ b ≤ 0.1);

[0070] Li a CoG b O2(0.90 ≤ a ≤ 1.8, 0.001 ≤ b ≤ 0.1);

[0071] Li a Mn 1-b G b O2(0.90 ≤ a ≤ 1.8, 0.001 ≤ b ≤ 0.1);

[0072] Li a Mn2G b O4(0.90 ≤ a ≤ 1.8, 0.001 ≤ b ≤ 0.1);

[0073] Li a Mn 1-g G g PO4(0.90 ≤ a ≤ 1.8, 0 ≤ g ≤ 0.5);

[0074] QO2; QS2; LiQS2;

[0075] V2O5; LiV2O5;

[0076] LiZO2;

[0077] LiNiVO4;

[0078] Li (3-f) J2(PO4)3(0 ≤ f ≤ 2);

[0079] Li (3-f) Fe2(PO4)3(0 ≤ f ≤ 2);

[0080] Li a FePO4(0.90 ≤ a ≤ 1.8).

[0081] 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.

[0082] 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).

[0083] 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.

[0084] [Chemical Formula 1]

[0085] Li a1 Ni x1 M 1 y1 M 2 1-x1-y1 O2

[0086] 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.

[0087] [Chemical Formula 2]

[0088] Li a2 Co x2 M 3 1-x2 O2

[0089] 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.

[0090] [Chemical Formula 3]

[0091] Li a3 Fe x3 M 4 (1-x3) PO4

[0092] 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.

[0093] 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.

[0094] 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.

[0095] Sulfide-based solid electrolyte

[0096] 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.

[0097] 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.

[0098] 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.

[0099] 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.

[0100] 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.

[0101] 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.

[0102] 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.

[0103] 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.

[0104] 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.

[0105] bookbinder

[0106] 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.

[0107] Challenge

[0108] 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.

[0109] 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.

[0110] 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.

[0111] 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.

[0112] All-solid-state secondary battery

[0113] In one embodiment, an all-solid-state secondary battery is provided, which includes 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.

[0114] 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 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 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.

[0115] cathode

[0116] 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.

[0117] 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.

[0118] 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.

[0119] 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.

[0120] 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.

[0121] 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.

[0122] 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.

[0123] 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.

[0124] 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.

[0125] 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.

[0126] The above binder serves to adhere the negative electrode active material particles well to each other and also to adhere the negative electrode active material well to the current collector. The binder may include an insoluble binder, a water-soluble binder, or a combination thereof.

[0127] 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.

[0128] 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.

[0129] 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.

[0130] 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.

[0131] 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.

[0132] 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.

[0133] 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, 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.

[0134] The above cathode coating layer (405) may include a metal, a carbon material, or a combination thereof that acts as a catalyst.

[0135] 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.

[0136] 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.

[0137] 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.

[0138] 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.

[0139] 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.

[0140] 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 ㎛.

[0141] 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.

[0142] solid electrolyte layer

[0143] 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.

[0144] 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.

[0145] 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.

[0146] 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.

[0147] 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.

[0148] The thickness of the solid electrolyte layer may be, for example, 10 ㎛ to 150 ㎛.

[0149] The above solid electrolyte layer may further include an alkali metal salt, and / or an ionic liquid, and / or a conductive polymer.

[0150] 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.

[0151] The 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.

[0152] 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.

[0153] 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.

[0154] 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-.

[0155] 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.

[0156] 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.

[0157] 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.

[0158] 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.

[0159] FIG. 3 is a cross-sectional view of an all-solid-state secondary battery according to a first embodiment of the present invention, FIG. 4 is a cross-sectional view of a state before zigzag laminating a negative electrode, a first solid electrolyte layer, a second solid electrolyte layer, a first positive electrode, and a second positive electrode to manufacture the all-solid-state secondary battery of FIG. 3, and FIG. 5 is a cross-sectional view of a unit cell formed of the negative electrode, the solid electrolyte layer, and the positive electrode in FIG. 4.

[0160] Referring to FIGS. 3 and 4, the all-solid-state secondary battery of the first embodiment includes a band-shaped negative electrode (10), a first solid electrolyte layer (21) and a second solid electrolyte layer (22) provided on both sides of the negative electrode (10), respectively, and first and second positive electrodes (31, 32) laminated on the first and second solid electrolyte layers (21, 22), respectively. The second positive electrode (32) is spaced apart from the first positive electrode (31) in the longitudinal direction of the negative electrode (10).

[0161] The negative electrode (10) is formed in a long strip shape and folded and stacked in a zigzag pattern, and the first positive electrode (31) and the second positive electrode (32) are alternately arranged between the folded and stacked negative electrodes (10). That is, in Fig. 3, from the bottom to the top, the negative electrode (10), the first positive electrode (31), the negative electrode (10), the second positive electrode (32), and the negative electrode (10) are repeatedly stacked and arranged.

[0162] Each of the first positive electrode (31) and the second positive electrode (32) includes a thin film metal positive electrode substrate (311, 321), and a first positive electrode active material layer (312) and a second positive electrode active material layer (322) formed on both sides of the positive electrode substrate (311, 321).

[0163] The negative electrode (10) includes functional layers (112, 113) formed on both sides of a negative electrode substrate (11) made of a thin film metal. Each of the first solid electrolyte layer (21) and the second solid electrolyte layer (22) is formed on each functional layer (112, 113) on both sides of the negative electrode substrate (11).

[0164] In an all-solid-state secondary battery in a zigzag stacked state, each of the first solid electrolyte layer (21) and the second solid electrolyte layer alternately corresponds to the side end of the first positive electrode (31) and the side end of the second positive electrode (32).

[0165] The functional layer (112, 113) of the negative electrode (10) is formed as a coating layer of a polymer or ceramic material on the negative electrode substrate (11). When the negative electrode (10) is provided with the functional layer (112, 113) and the first and second solid electrolyte layers (21, 22), an all-solid-state secondary battery is formed.

[0166] Additionally, the functional layer (112, 113) can be formed by bonding a separator to the negative electrode material (11). In this case, the first and second solid electrolyte layers (21, 22) are not provided, so that a lithium ion secondary battery can be formed.

[0167] Referring to Fig. 5, in the all-solid-state secondary battery of the first embodiment, a unit cell (UC1) is formed between a negative electrode substrate (11) and a positive electrode substrate (311). That is, the unit cell (UC1) is formed with a laminated structure of a positive electrode substrate (311) of a first positive electrode (31), a first positive electrode active material layer (312), a first solid electrolyte layer (21), a functional layer (112), and a negative electrode substrate (11).

[0168] An all-solid-state secondary battery having a precipitated negative electrode (10) starts initial charging in a state in which no negative active material is present, and when charging, a high-density lithium metal or the like is precipitated between the negative electrode substrate (11) and the functional layer (112, 113) to form a lithium metal layer, and the lithium metal layer can serve as a negative active material.

[0169] Hereinafter, various embodiments of the present invention will be described. Descriptions of configurations identical to those of the previously described embodiments will be omitted, and descriptions of configurations that are different from them will be provided.

[0170] Fig. 6 is a cross-sectional view of a unit cell formed of a negative electrode, a solid electrolyte layer, and a positive electrode in an all-solid-state secondary battery according to a second embodiment of the present invention. Referring to Fig. 6, in the all-solid-state secondary battery of the second embodiment, a unit cell (UC2) is formed by a laminated structure of a positive electrode substrate (311) of a first positive electrode (31), a first positive electrode active material layer (312), a first solid electrolyte layer (21), and a negative electrode substrate (211) of a negative electrode (210).

[0171] The negative electrode (210) is formed of lithium metal and does not have the functional layer of the first embodiment. Therefore, each of the first solid electrolyte layer (21) and the second solid electrolyte layer (22) is formed on lithium metal on both sides.

[0172] An all-solid-state secondary battery having a precipitated negative electrode (210) starts initial charging in a state in which no negative electrode active material exists, and when charging, a high-density lithium metal or the like is precipitated on the negative electrode substrate (11) formed of lithium metal to form a lithium metal layer, and the lithium metal layer can serve as a negative electrode active material.

[0173] Fig. 7 is a cross-sectional view of a unit cell formed of a negative electrode, a solid electrolyte layer, and a positive electrode in an all-solid-state secondary battery according to a third embodiment of the present invention. Referring to Fig. 7, in the all-solid-state secondary battery of the third embodiment, a unit cell (UC3) is formed by a laminated structure of a positive electrode substrate (311) of a first positive electrode (31), a first positive electrode active material layer (312), a first solid electrolyte layer (21), a metal pattern (114), and a negative electrode substrate (11).

[0174] The negative electrode (310) includes a metal pattern (114) formed on both sides of the negative electrode material (11). Accordingly, each of the first solid electrolyte layer (21) and the second solid electrolyte layer (22) is formed on each metal pattern (114) on both sides. The metal pattern (114) may be formed as a lithium metal pattern or an aluminum metal pattern.

[0175] An all-solid-state secondary battery having a precipitation-type negative electrode (210) starts initial charging in a state in which no negative active material is present, and when charging, high-density lithium metal or the like is precipitated between the negative electrode substrate (11) in contact with the empty space within the metal pattern (114) and the empty space within the metal pattern (114), thereby forming a lithium metal layer to minimize thickness change, and the lithium metal layer can function as a negative active material. In addition, when the metal pattern (114) reacts with lithium, some alloys may be formed. For example, when the metal pattern is a metal such as aluminum (Al) or silicon (Si), some alloys may be formed by reacting with lithium.

[0176] FIG. 8 is a cross-sectional view illustrating a step of forming a laminate in a manufacturing method of manufacturing an all-solid-state secondary battery using an all-solid-state secondary battery manufacturing apparatus according to an embodiment of the present invention, FIG. 9 is a perspective view of a lamination guide applied to the all-solid-state secondary battery manufacturing apparatus of FIG. 8, FIG. 10 is a cross-sectional view of taking out an all-solid-state secondary battery in a manufacturing method using the all-solid-state secondary battery manufacturing apparatus of FIG. 8, and FIG. 11 is a perspective view of a first embodiment of forming a laminate in a manufacturing method of manufacturing an all-solid-state secondary battery using an all-solid-state secondary battery manufacturing apparatus according to an embodiment of the present invention.

[0177] Referring to FIGS. 8 to 11, an all-solid-state secondary battery manufacturing device of one embodiment includes a laminate forming unit (60), a pair of laminate guides (70), an actuator (75), and a high-temperature press (80). For convenience, the all-solid-state secondary battery of the first embodiment of FIGS. 3 to 5 will be described as an example.

[0178] The laminate forming part (60) is configured so that the negative electrode (10) is folded and stacked in a zigzag pattern, and the first positive electrode (31) and the second positive electrode (32) are alternately arranged between the folded and stacked layers to form a final laminate (SA, Stacking Assembly).

[0179] Referring to Fig. 9, the stacking guides (70) are formed as a pair to support the lower and side surfaces of the stack (SA) and are arranged oppositely on both sides in the zigzag width direction. As an example, the stacking guide (70) includes a lower plate (71), a front plate (72), a rear plate (73), and a side plate (74) to three-dimensionally support the stack (SA).

[0180] The lower plate (71) is formed corresponding to the lower surface of the laminate (SA). The front plate (72) and the rear plate (73) extend upward from the lower plate (71) to support the front and rear sides of the laminate (SA) on the side adjacent to the laminate (SA) on the lower plate (71). The side plate (74) extends upward from the lower plate (71) to support the side surfaces of the laminate (SA) on the side distal from the laminate (SA) on the lower plate (71).

[0181] The actuator (75) is connected to the stacking guide (70) to control the movement of the stacking guide (70) in the width direction (x-axis direction). That is, the actuator (75) is connected to the side plate (74) and operates to expand and contract, so that the stacking guide (70) can be moved forward and backward in the x-axis direction.

[0182] The actuator (75) can be connected to a pair of stacking guides (70) in the same manner. In addition, the actuator (75) can be formed only on one of the stacking guides (70) of the pair, so that one can be used as a fixed type and the other can be used as a movable type.

[0183] Referring again to FIG. 8, the high-temperature press (80) presses the laminate (SA) supported by the laminate guide (70). At this time, the lower plate (71), front plate (72), rear plate (73), and side plate (74) of the laminate guide (70) set the shape of the laminate (SA).

[0184] Accordingly, the positive electrode substrate (311), the first positive electrode active material layer (312), the first solid electrolyte layer (21), the functional layer (112), the negative electrode substrate (11), the functional layer (113), the second solid electrolyte layer (22), the second positive electrode active material layer (322) and the positive electrode substrate (321) of the second positive electrode (32) forming a unit cell (UC1) within the laminate (SA) form a close bonding structure.

[0185] Referring again to FIG. 11, the laminate forming unit (60) of the first embodiment includes an upper roll (61) and a lower roll (62). The laminate forming unit (60) laminates a first positive electrode (31) by introducing it into a first solid electrolyte layer (21) provided on one side of a band-shaped negative electrode (10) that runs between the upper roll (61) and the lower roll (62), and laminates a second positive electrode (32) by introducing it into a second solid electrolyte layer (22) provided on the other side of the negative electrode (10) and spaced apart from the first positive electrode (31) in the longitudinal direction of the negative electrode (10), and pressurizes it while running together with the negative electrode (10). Accordingly, the laminated first positive electrode (31), first solid electrolyte layer (21), negative electrode (10), second solid electrolyte layer (22), and second positive electrode (32) pass between the upper roll (61) and the lower roll (62) of the laminate forming part (60), thereby forming a laminate (SA1) in a state before bending (see FIG. 4).

[0186] The spacing between the first and second positive electrodes (31, 32) in the longitudinal direction of the negative electrode (10) corresponds to the pitch at which the first and second positive electrodes (31, 32) are laminated in a zigzag fold. The laminate forming unit (60) may include a separate feeder (not shown) for feeding the first positive electrode (31) and the second positive electrode (32) as individual sheets onto both sides of the negative electrode (10).

[0187] Below, various embodiments of the laminated body forming unit (60) are described. Descriptions of configurations identical to those of the previously described embodiments are omitted, and descriptions of configurations that are different from each other are described.

[0188] FIG. 12 is a perspective view of a second embodiment of a manufacturing method for manufacturing an all-solid-state secondary battery using an all-solid-state secondary battery manufacturing apparatus according to one embodiment of the present invention, wherein a laminate is formed.

[0189] Referring again to FIG. 12, the laminate forming unit (260) of the second embodiment includes an upper roll (61) and a lower roll (62). The laminate forming unit (260) supplies a first positive electrode (31) attached to the upper roll (61) and a second positive electrode (32) attached to the lower roll (62). The laminate forming unit (260) laminates a first positive electrode (31) on a first solid electrolyte layer (21) provided on one surface of a negative electrode (10) along which a belt-shaped negative electrode (10) advances, and laminates a second positive electrode (32) on a second solid electrolyte layer (22) spaced apart from the first positive electrode (31) in the longitudinal direction of the negative electrode (10), and applies pressure with the upper roll (61) and the lower roll (62) while advancing together with the negative electrode (10). Accordingly, the laminated first positive electrode (31), first solid electrolyte layer (21), negative electrode (10), second solid electrolyte layer (22), and second positive electrode (32) pass between the upper roll (61) and the lower roll (62) of the laminate forming part (260), thereby forming a laminate (SA2) in a state before bending.

[0190] The spacing between the first and second positive electrodes (31, 32) in the longitudinal direction of the negative electrode (10) corresponds to the pitch at which the first and second positive electrodes (31, 32) are laminated in a zigzag fold. The laminate forming unit (260) may include a separate feeder (not shown) for feeding the first positive electrode (31) and the second positive electrode (32) individually to the upper roll (61) and the lower roll (62), respectively.

[0191] Fig. 13 is a side view of a third embodiment of a method for manufacturing an all-solid-state secondary battery using an all-solid-state secondary battery manufacturing apparatus according to an embodiment of the present invention, in which a laminate is formed. Referring to Fig. 13, a laminate forming unit (360) of the third embodiment laminates a first positive electrode (31) on a first solid electrolyte layer (21) provided on one surface of a negative electrode (10) along which a band-shaped negative electrode (10) advances, supplies the first positive electrode (31) by attaching it to a first plate (81), and pressurizes and attaches the first positive electrode (31) to one surface of the negative electrode (10) by applying pressure with a first roll (83).

[0192] In addition, the laminate forming unit (360) supplies the second positive electrode (32) by attaching it to the second plate (82) so that the second positive electrode (32) is laminated on the second solid electrolyte layer (22) in a longitudinal direction of the negative electrode (10) apart from the first positive electrode (31), and pressurizes and attaches the second positive electrode (32) to the other side of the negative electrode (10) by applying pressure with the second roll (84).

[0193] Accordingly, the laminated first positive electrode (31), first solid electrolyte layer (21), negative electrode (10), second solid electrolyte layer (22), and second positive electrode (32) pass between the first and second plates (81, 82) and the first and second rolls (83, 84) of the laminate forming portion (360), thereby forming a laminate (SA3) in a state before folding.

[0194] The laminate forming unit (360) is provided with a return roll (87) so that the direction of travel of the first plate (81) is opposite to the direction of travel of the second plate (82), thereby shortening the length of travel of the negative electrode (10) in the laminate forming unit (360).

[0195] Fig. 14 is a side view of a fourth embodiment of a method for manufacturing an all-solid-state secondary battery using an all-solid-state secondary battery manufacturing apparatus according to an embodiment of the present invention, in which a laminate is formed. Referring to Fig. 14, a laminate forming unit (460) of the fourth embodiment supplies a first positive electrode (31) by attaching it to a first plate (81) so that the first positive electrode (31) is laminated on a first solid electrolyte layer (21) provided on one surface of the negative electrode (10) along which the band-shaped negative electrode (10) advances, and pressurizes and attaches the first positive electrode (31) to one surface of the negative electrode (10) by applying pressure from a first press (85).

[0196] In addition, the laminate forming part (460) is supplied by attaching the second positive electrode (32) to the second plate (82) so that the second positive electrode (32) is laminated on the second solid electrolyte layer (22) in a longitudinal direction of the negative electrode (10) apart from the first positive electrode (31), and the second positive electrode (32) is pressurized and attached to the other side of the negative electrode (10) by applying pressure from the second press (86).

[0197] Accordingly, the laminated first positive electrode (31), first solid electrolyte layer (21), negative electrode (10), second solid electrolyte layer (22), and second positive electrode (32) pass between the first and second plates (81, 82) and the first and second presses (85, 86) of the laminate forming portion (360), thereby forming a laminate (SA4) in a state before bending.

[0198] The laminate forming unit (660) is provided with a return roll (87) so that the direction of travel of the first plate (81) is opposite to the direction of travel of the second plate (82), thereby shortening the length of travel of the negative electrode (10) in the laminate forming unit (360).

[0199] Fig. 15 is a side view of a fifth embodiment of a method for forming a laminate in a method for manufacturing an all-solid-state secondary battery using an all-solid-state secondary battery manufacturing apparatus according to an embodiment of the present invention. Referring to Fig. 15, the laminate forming unit (560) of the fifth embodiment supplies the first positive electrode (31) between the left roll (91) and the first solid electrolyte layer (21) so as to laminate the first positive electrode (31) on the first solid electrolyte layer (21) provided on one surface of the negative electrode (10) in which the band-shaped negative electrode (10) advances upward.

[0200] In addition, the laminate forming unit (560) supplies the second positive electrode (32) between the right roll (92) and the second solid electrolyte layer (22) so as to laminate the second positive electrode (32) on the second solid electrolyte layer (22) in a longitudinal direction of the negative electrode (10) and spaced apart from the first positive electrode (31).

[0201] And as the laminated first positive electrode (31), first solid electrolyte layer (21), negative electrode (10), second solid electrolyte layer (22) and second positive electrode (32) pass between the left roll (91) and the right roll (92), a laminate (SA5) in a state before bending is formed by the pressure of the left roll (91) and the right roll (92).

[0202] Fig. 16 is a side view of a sixth embodiment of a method for forming a laminate in a method for manufacturing an all-solid-state secondary battery using an all-solid-state secondary battery manufacturing apparatus according to an embodiment of the present invention. Referring to Fig. 16, the laminate forming unit (660) of the sixth embodiment supplies the first positive electrode (31) between the left roll (91) and the first solid electrolyte layer (21) so as to laminate the first positive electrode (31) on the first solid electrolyte layer (21) provided on one surface of the negative electrode (10) in which the belt-shaped negative electrode (10) advances downward.

[0203] In addition, the laminate forming unit (660) supplies the second positive electrode (32) between the right roll (92) and the second solid electrolyte layer (22) so as to form the second positive electrode (32) to be laminated on the second solid electrolyte layer (22) spaced apart from the first positive electrode (31) in the longitudinal direction of the negative electrode (10).

[0204] And as the laminated first positive electrode (31), first solid electrolyte layer (21), negative electrode (10), second solid electrolyte layer (22) and second positive electrode (32) pass between the left roll (91) and the right roll (92), a laminate (SA6) in a state before bending is formed by the pressure of the left roll (91) and the right roll (92).

[0205] Below, a method for manufacturing an all-solid-state secondary battery using an all-solid-state secondary battery manufacturing device of one embodiment is described.

[0206] Figure 17 is a flowchart of a method for manufacturing an all-solid-state secondary battery according to one embodiment of the present invention. Referring to Figures 8 to 11 and Figure 17, the method for manufacturing an all-solid-state secondary battery according to one embodiment includes a first step (ST1), a second step (ST2), a third step (ST3), and a fourth step (ST4).

[0207] The first stage (ST1) includes a band-shaped negative electrode (10), a first solid electrolyte layer (21) and a second solid electrolyte layer (22) provided on each side of the negative electrode (10), a first positive electrode (31) laminated on the first solid electrolyte layer (21), and a second positive electrode (32) laminated on the second solid electrolyte layer (22) and spaced apart from the first positive electrode (31) in the longitudinal direction of the negative electrode (10), and the negative electrode (10) is folded and laminated in a zigzag manner, and the first positive electrode (31) and the second positive electrode (32) are alternately arranged between the folded and laminated layers to form a laminate (SA).

[0208] The second step (ST2) supports the lower surface and the side surface of the laminate (SA) with a pair of lamination guides (70) that are arranged oppositely on both sides in the zigzag width direction and advanced by an actuator (75). The third step (ST3) presses the laminate (SA) supported by the lamination guides (70) with a high-temperature press (80). The fourth step (ST4) retracts the lamination guides (70) that support the lower surface and the side surface of the pressed laminate (SA) with an actuator (75) to remove the laminate (SA) from the lamination guides (70).

[0209] Referring to FIG. 11, in the manufacturing method of the first embodiment, the first step (ST1) includes an 11th step of laminating a first positive electrode (31) on a first solid electrolyte layer (21) provided on one surface of a negative electrode (10) along which a band-shaped negative electrode (10) advances, a 12th step of laminating a second positive electrode (32) on a second solid electrolyte layer (22) spaced apart from the first positive electrode (31) in the longitudinal direction of the negative electrode (10), and a 13th step of pressing the first positive electrode (31), the negative electrode (10), and the second positive electrode (32) with an upper roll (61) and a lower roll (62). Accordingly, the first positive electrode (31), the negative electrode (10), and the second positive electrode (32) form a laminate (SA1) in a state before bending.

[0210] Referring to FIG. 12, in the manufacturing method of the second embodiment, the first step (ST1) includes an 11th step of supplying the first positive electrode (31) by attaching it to the upper roll (61) so that the first positive electrode (31) is laminated on the first solid electrolyte layer (21) provided on one surface of the negative electrode (10) on which the negative electrode (10) in the band is advanced, a 12th step of supplying the second positive electrode (32) by attaching it to the lower roll (62) so that the second positive electrode (32) is laminated on the second solid electrolyte layer (22) spaced apart from the first positive electrode (31) in the longitudinal direction of the negative electrode (10), and a 13th step of pressing the first positive electrode (31), the negative electrode (10), and the second positive electrode (32) with the upper roll (61) and the lower roll (62). Accordingly, the first positive electrode (31), the negative electrode (10), and the second positive electrode (32) form a laminate (SA2) in a state before folding.

[0211] Referring to FIG. 13, in the manufacturing method of the third embodiment, the first step (ST1) is an 11th step of supplying the first positive electrode (31) by attaching it to the first plate (81) so that the first positive electrode (31) is laminated on the first solid electrolyte layer (21) provided on one side of the negative electrode (10) through which the negative electrode (10) in the form of a belt is advanced, a 12th step of pressurizing and attaching the first positive electrode (31) to one side of the negative electrode (10) by applying pressure between the first plate (81) and the first roll (83), a 13th step of supplying the second positive electrode (32) by attaching it to the second plate (82) so that the second positive electrode (32) is laminated on the second solid electrolyte layer (22) spaced apart from the first positive electrode (31) in the longitudinal direction of the negative electrode (10), and a 14th step of supplying the second positive electrode (32) by attaching it to the second plate (82) so that the second positive electrode (32) is laminated on the second solid electrolyte layer (22) and It includes a 14th step of pressurizing and attaching the second positive electrode (32) to the other side of the negative electrode (10) by applying pressure with the second roll (84). Accordingly, the first positive electrode (31), the negative electrode (10), and the second positive electrode (32) form a laminate (SA3) in a state before folding.

[0212] Referring to FIG. 14, in the manufacturing method of the fourth embodiment, the first step is an 11th step of supplying the first positive electrode (31) by attaching it to the first plate (81) so that the first positive electrode (31) is laminated on the first solid electrolyte layer (21) provided on one side of the negative electrode (10) through which the negative electrode (10) in the form of a band is advanced, a 12th step of pressurizing and attaching the first positive electrode (31) to one side of the negative electrode (10) by applying pressure to the first plate (81) and the first press (85), a 13th step of supplying the second positive electrode (32) by attaching it to the second plate (82) so that the second positive electrode (32) is laminated on the second solid electrolyte layer (22) spaced apart from the first positive electrode (31) in the longitudinal direction of the negative electrode (10), and a 14th step of supplying the second positive electrode (32) by attaching it to the second plate (82) so that the second positive electrode (32) is laminated on the second solid electrolyte layer (22), and a 15th step of supplying the second positive electrode (32) by applying pressure to the second plate (82) and the second press (86). It includes a 14th step of pressurizing and attaching the second positive electrode (32) to the other side of the negative electrode (10). Accordingly, the first positive electrode (31), the negative electrode (10), and the second positive electrode (32) form a laminate (SA4) in a state before folding.

[0213] Referring to FIG. 15, in the manufacturing method of the fifth embodiment, the first step (ST1) is an eleventh step of supplying the first positive electrode (31) between the left roll (91) and the first solid electrolyte layer (21) so that the first positive electrode (31) is laminated on the first solid electrolyte layer (21) provided on one surface of the negative electrode (10) in which the negative electrode (10) in the belt shape advances upward, a twelfth step of supplying the second positive electrode (32) between the right roll (92) and the second solid electrolyte layer (22) so that the second positive electrode (32) is laminated on the second solid electrolyte layer (22) spaced apart from the first positive electrode (31) in the longitudinal direction of the negative electrode (10), and a twelfth step of pressing the first positive electrode (31), the negative electrode (10), and the second positive electrode (32) with the left roll (91) and the right roll (92). Step 13 is included. Therefore, the first positive electrode (31), the negative electrode (10), and the second positive electrode (32) form a laminate (SA5) in a state before folding.

[0214] Referring to FIG. 16, in the manufacturing method of the sixth embodiment, the first step (ST1) is an eleventh step of supplying the first positive electrode (31) between the left roll (91) and the first solid electrolyte layer (21) so as to laminate the first positive electrode (31) on the first solid electrolyte layer (21) provided on one surface of the negative electrode (10) in which the negative electrode (10) in the belt shape advances downward, a twelfth step of supplying the second positive electrode (32) between the right roll (92) and the second solid electrolyte layer (22) so as to laminate the second positive electrode (32) on the second solid electrolyte layer (22) spaced apart from the first positive electrode (31) in the longitudinal direction of the negative electrode (10), and a twelfth step of pressing the first positive electrode (31), the negative electrode (10), and the second positive electrode (32) with the left roll (91) and the right roll (92). Step 13 is included. Therefore, the first positive electrode (31), the negative electrode (10), and the second positive electrode (32) form a laminate (SA6) in a state before folding.

[0215] 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.

[0216] - Explanation of symbols -

[0217] 10: Negative electrode 21: First solid electrolyte layer

[0218] 22: Second solid electrolyte layer 31, 32: First and second positive electrodes

[0219] 60: Laminate forming section 61: Upper roll

[0220] 62: Lower roll 70: Laminated guide

[0221] 71: Lower plate 72: Front plate

[0222] 73: Back plate 74: Side plate

[0223] 75: Actuator 80: High-temperature press

[0224] 81, 82: 1st and 2nd plates 83: 1st roll

[0225] 84: Second roll 85: First press

[0226] 86: Second press 87: Return roll

[0227] 91: Left roll 92: Right roll

[0228] 112, 113: Functional layer 114: Metal pattern

[0229] 210: Negative electrode 260: Laminate formation part

[0230] 311, 321: Cathode material 312, 322: First and second cathode active material layers

[0231] 360: Laminate forming part 460: Laminate forming part

[0232] 560: Laminate forming part 660: Laminate forming part

[0233] UC1: Unit cell UC2: Unit cell

[0234] UC3: Unit cell SA: Stack

[0235] SA1: Laminate SA2: Laminate

[0236] SA3: Laminate SA4: Laminate

[0237] SA5: Laminate SA6: Laminate

Claims

1. Negative electrode on the belt; A first solid electrolyte layer and a second solid electrolyte layer provided on each side of the negative electrode; A first positive electrode laminated on the first solid electrolyte layer; and A second positive electrode is laminated on the second solid electrolyte layer and is spaced apart from the first positive electrode in the longitudinal direction of the negative electrode, The above negative electrode Folded and stacked in a zigzag pattern, The above first positive electrode and the above second positive electrode An all-solid-state secondary battery in which layers are alternately arranged between folded layers.

2. In paragraph 1, Each of the first positive electrode and the second positive electrode Bipolar materials, and An all-solid-state secondary battery comprising a first positive electrode active material layer and a second positive electrode active material layer formed on both sides of the above positive electrode substrate.

3. In paragraph 1, The above negative electrode Includes a functional layer formed on both sides of the cathode substrate, An all-solid-state secondary battery, wherein each of the first solid electrolyte layer and the second solid electrolyte layer is formed on each functional layer on both sides.

4. In paragraph 3, The above first solid electrolyte layer and the above second solid electrolyte layer are each An all-solid-state secondary battery, wherein the side ends of the first positive electrode and the side ends of the second positive electrode alternately correspond to each other.

5. In paragraph 3, The above functional layer An all-solid-state secondary battery formed with a coating layer of polymer or ceramic material on the above-mentioned negative electrode material.

6. In paragraph 3, The above functional layer An all-solid-state secondary battery formed by bonding a separator to the above-mentioned negative electrode material.

7. In paragraph 1, The above negative electrode is, It is formed from lithium metal, An all-solid-state secondary battery, wherein each of the first solid electrolyte layer and the second solid electrolyte layer is formed on lithium metal on both sides.

8. In paragraph 1, The above negative electrode is, Includes a metal pattern formed on both sides of the cathode substrate, An all-solid-state secondary battery, wherein each of the first solid electrolyte layer and the second solid electrolyte layer is formed on a respective metal pattern on both sides.

9. A laminate forming part comprising a negative electrode on a belt, a first solid electrolyte layer and a second solid electrolyte layer respectively provided on both sides of the negative electrode, a first positive electrode laminated on the first solid electrolyte layer, and a second positive electrode laminated on the second solid electrolyte layer and spaced apart from the first positive electrode in the longitudinal direction of the negative electrode, wherein the negative electrode is folded and laminated in a zigzag manner, and the first positive electrode and the second positive electrode are alternately arranged between the folded and laminated portions to form a laminate; A pair of lamination guides formed to support the lower surface and side surfaces of the laminate and arranged oppositely on both sides in the zigzag width direction; An actuator connected to the stacking guide to control movement of the stacking guide in the width direction; and An all-solid-state secondary battery manufacturing device including a high-temperature press that presses the laminate supported by the laminate guide.

10. In paragraph 9, The above layering guide A lower plate corresponding to the lower surface of the above laminate, A front plate and a rear plate extending upward from the lower plate to support the front and rear sides of the laminate on the adjacent side of the laminate, and A side plate extending upward from the lower plate to support the side surface of the laminate from the lower plate. An all-solid-state secondary battery manufacturing device including:

11. In paragraph 9, The above laminated body forming part is, An all-solid-state secondary battery manufacturing device that laminates a first positive electrode on a first solid electrolyte layer provided on one side of the negative electrode on which a negative electrode on a belt advances, laminates a second positive electrode on a second solid electrolyte layer spaced apart from the first positive electrode in the longitudinal direction of the negative electrode, and applies pressure with an upper roll and a lower roll.

12. In paragraph 9, The above laminated body forming part is, An upper roll that supplies the first positive electrode, and It includes a lower roll that supplies the second positive electrode that is spaced apart from the first positive electrode in the longitudinal direction of the negative electrode, An all-solid-state secondary battery manufacturing device that laminates a first positive electrode on a first solid electrolyte layer provided on one side of the negative electrode on which a negative electrode on a belt advances, laminates a second positive electrode on a second solid electrolyte layer spaced apart from the first positive electrode in the longitudinal direction of the negative electrode, and applies pressure with the upper roll and the lower roll.

13. In paragraph 9, The above laminated body forming part is, The first positive electrode is supplied by attaching the first positive electrode to the first plate so that the first positive electrode is laminated on the first solid electrolyte layer provided on one side of the negative electrode on which the negative electrode on the belt advances, and the first positive electrode is pressurized and attached to one side of the negative electrode by applying pressure with the first roll. An all-solid-state secondary battery manufacturing device that supplies a second positive electrode by attaching the second positive electrode to a second plate so that the second positive electrode is laminated on the second solid electrolyte layer while being spaced apart from the first positive electrode in the longitudinal direction of the negative electrode, and pressurizes and attaches the second positive electrode to the other side of the negative electrode by applying pressure with a second roll.

14. In paragraph 9, The above laminated body forming part is, The first positive electrode is supplied by attaching the first positive electrode to the first plate so that the first positive electrode is laminated on the first solid electrolyte layer provided on one side of the negative electrode on which the negative electrode on the belt advances, and the first positive electrode is pressurized and attached to one side of the negative electrode by applying pressure from the first press. An all-solid-state secondary battery manufacturing device that supplies a second positive electrode by attaching the second positive electrode to a second plate so that the second positive electrode is laminated on the second solid electrolyte layer while being spaced apart from the first positive electrode in the longitudinal direction of the negative electrode, and pressurizes and attaches the second positive electrode to the other side of the negative electrode by applying pressure from a second press.

15. In paragraph 9, The above laminated body forming part is, The first positive electrode is supplied between the left roll and the first solid electrolyte layer so that the first positive electrode is laminated on the first solid electrolyte layer provided on one side of the negative electrode on the belt, where the negative electrode advances upward. The second positive electrode is supplied between the right roll and the second solid electrolyte layer so as to be stacked on the second solid electrolyte layer, spaced apart from the first positive electrode in the longitudinal direction of the negative electrode. An all-solid-state secondary battery manufacturing device that applies pressure with the left roll and the right roll.

16. In paragraph 9, The above laminated body forming part is, The first positive electrode is supplied between the left roll and the first solid electrolyte layer so that the first positive electrode is laminated on the first solid electrolyte layer provided on one side of the negative electrode on the belt, which progresses downward, and The second positive electrode is supplied between the right roll and the second solid electrolyte layer so as to be stacked on the second solid electrolyte layer, spaced apart from the first positive electrode in the longitudinal direction of the negative electrode. An all-solid-state secondary battery manufacturing device that applies pressure with the left roll and the right roll.

17. A first step of forming a laminate, comprising: a negative electrode on a belt, a first solid electrolyte layer and a second solid electrolyte layer provided on each side of the negative electrode, a first positive electrode laminated on the first solid electrolyte layer, and a second positive electrode laminated on the second solid electrolyte layer and spaced apart from the first positive electrode in the longitudinal direction of the negative electrode; and a first step of forming a laminate by zigzag-bending and laminating the negative electrode and alternately arranging the first positive electrode and the second positive electrode between the folded and laminated layers; A second step of supporting the lower surface and the side surface of the laminate by a pair of laminate guides arranged oppositely on both sides of the zigzag width direction and advanced by an actuator; A third step of pressing the laminate supported on the laminate guide with a high temperature press; and A fourth step of removing the laminate by retracting the laminate guide supporting the lower surface and side surface of the laminate after pressurization using the actuator. A method for manufacturing an all-solid-state secondary battery comprising:

18. In paragraph 17, The above first step is An 11th step of laminating a first positive electrode on a first solid electrolyte layer provided on one side of the negative electrode on which the negative electrode on the belt progresses; A 12th step of laminating a second positive electrode on the second solid electrolyte layer, spaced apart from the first positive electrode in the longitudinal direction of the negative electrode, and Step 13 of pressurizing the first positive electrode, the negative electrode, and the second positive electrode with the upper roll and the lower roll A method for manufacturing an all-solid-state secondary battery comprising:

19. In paragraph 17, The above first step is, An 11th step of supplying the first positive electrode by attaching it to the upper roll so that the first positive electrode is laminated on the first solid electrolyte layer provided on one side of the negative electrode on which the negative electrode on the belt progresses. A 12th step of supplying the second positive electrode by attaching it to the lower roll so that the second positive electrode is laminated on the second solid electrolyte layer while being spaced apart from the first positive electrode in the longitudinal direction of the negative electrode, and Step 13 of pressurizing the first positive electrode, the negative electrode, and the second positive electrode with the upper roll and the lower roll A method for manufacturing an all-solid-state secondary battery comprising:

20. In paragraph 17, The above first step is, An 11th step of supplying the first positive electrode by attaching it to the first plate so that the first positive electrode is laminated on the first solid electrolyte layer provided on one side of the negative electrode on which the negative electrode on the belt progresses. A 12th step of pressurizing and attaching the first positive electrode to one side of the negative electrode by applying pressure to the first plate and the first roll; A 13th step of supplying the second positive electrode by attaching it to the second plate so that the second positive electrode is laminated on the second solid electrolyte layer, spaced apart from the first positive electrode in the longitudinal direction of the negative electrode, and Step 14 of pressurizing and attaching the second positive electrode to the other side of the negative electrode by applying pressure to the second plate and the second roll. A method for manufacturing an all-solid-state secondary battery comprising:

21. In paragraph 17, The above first step is, An 11th step of supplying the first positive electrode by attaching it to the first plate so that the first positive electrode is laminated on the first solid electrolyte layer provided on one side of the negative electrode on which the negative electrode on the belt progresses. Step 12 of pressurizing and attaching the first positive electrode to one side of the negative electrode by applying pressure to the first plate and the first press; A 13th step of supplying the second positive electrode by attaching it to the second plate so that the second positive electrode is laminated on the second solid electrolyte layer, spaced apart from the first positive electrode in the longitudinal direction of the negative electrode, and Step 14 of pressurizing and attaching the second positive electrode to the other side of the negative electrode by applying pressure to the second plate and the second press. A method for manufacturing an all-solid-state secondary battery comprising:

22. In paragraph 17, The above first step is, An 11th step of supplying the first positive electrode between the left roll and the first solid electrolyte layer so as to laminate the first positive electrode on the first solid electrolyte layer provided on one side of the negative electrode on the belt, in which the negative electrode advances upward. A 12th step of supplying the second positive electrode between the right roll and the second solid electrolyte layer so as to laminate the second positive electrode on the second solid electrolyte layer while being spaced apart from the first positive electrode in the longitudinal direction of the negative electrode, and Step 13 of pressurizing the first positive electrode, the negative electrode, and the second positive electrode with the left roll and the right roll A method for manufacturing an all-solid-state secondary battery comprising:

23. In paragraph 17, The above first step is, An 11th step of supplying the first positive electrode between the left roll and the first solid electrolyte layer so as to laminate the first positive electrode on the first solid electrolyte layer provided on one side of the negative electrode on the belt, which is moving downwards; A 12th step of supplying the second positive electrode between the right roll and the second solid electrolyte layer so as to laminate the second positive electrode on the second solid electrolyte layer while being spaced apart from the first positive electrode in the longitudinal direction of the negative electrode, and Step 13 of pressurizing the first positive electrode, the negative electrode, and the second positive electrode with the left roll and the right roll A method for manufacturing an all-solid-state secondary battery comprising:

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