All-solid-state battery

Abstract

An all-solid-state battery includes: a laminate including a first surface and a second surface opposite to each other in a first direction, the laminate including a positive electrode layer, a negative electrode layer, and a solid electrolyte layer disposed between the positive electrode layer and the negative electrode layer and including a solid electrolyte; a first thin film electrode directly connected to the positive electrode layer and the solid electrolyte layer on the first surface of the laminate; a second thin film electrode directly connected to the negative electrode layer and the solid electrolyte layer on the second surface of the laminate; a first external electrode connected to the first thin film electrode and covering at least a portion of the laminate; and a second external electrode connected to the second thin film electrode and covering at least a portion of the laminate.

Description

Technical Field

[0001] This disclosure relates to an all-solid-state battery. Background Technology

[0002] Recently, the need for miniaturization and long-term use of portable electronic devices has led to a demand for high-capacity batteries, and the proliferation of wearable electronic devices has also raised requirements for battery safety.

[0003] Currently, commercially available lithium-ion batteries use liquid electrolytes containing flammable organic solvents, which pose a risk of overheating and fire in the event of a short circuit. Therefore, the use of solid-state batteries, replacing liquid electrolytes, is being proposed.

[0004] If the electrode layer (positive or negative electrode layer) of an all-solid-state battery is not uniformly connected to the external electrode, it may hinder the stable flow of current, causing the battery to experience unstable charging and discharging. Summary of the Invention

[0005] Technical issues One aspect of the embodiments is to provide an all-solid-state battery that can ensure stable charging and discharging by uniformly connecting the electrode layer and the external electrode.

[0006] However, the problems to be solved by the embodiments of this disclosure are not limited to those described above, and various extensions can be made within the scope of the technical concepts included in this disclosure.

[0007] Solution to the problem An all-solid-state battery according to an embodiment includes: a stack comprising a first surface and a second surface opposite to each other in a first direction, a third surface and a fourth surface opposite to each other in a second direction and connecting the first surface and the second surface, and a fifth surface and a sixth surface opposite to each other in a third direction and connecting the first surface and the second surface, the stack comprising a positive electrode layer, a negative electrode layer and a solid electrolyte layer, the solid electrolyte layer being disposed between the positive electrode layer and the negative electrode layer and comprising a solid electrolyte; a first thin-film electrode directly connected to the positive electrode layer and the solid electrolyte layer on the first surface of the stack; a second thin-film electrode directly connected to the negative electrode layer and the solid electrolyte layer on the second surface of the stack; a first external electrode connected to the first thin-film electrode and covering at least a portion of the stack; and a second external electrode connected to the second thin-film electrode and covering at least a portion of the stack.

[0008] The first external electrode and the second external electrode may include silver (Ag).

[0009] The first external electrode and the second external electrode may include a matrix resin and a conductive metal, wherein the conductive metal comprises silver (Ag).

[0010] The matrix resin may include epoxy resin.

[0011] The first thin film electrode and the second thin film electrode can be sputtering electrodes.

[0012] The thickness of the first thin film electrode can be greater than or equal to 50 nm and less than or equal to 1 μm, and the thickness of the second thin film electrode can be greater than or equal to 50 nm and less than or equal to 1 μm.

[0013] The thickness of the first thin film electrode can be greater than or equal to 50 nm and less than or equal to 500 nm, and the thickness of the second thin film electrode can be greater than or equal to 50 nm and less than or equal to 500 nm.

[0014] The thickness of the first thin film electrode and the thickness of the second thin film electrode may be greater than or equal to 50 nm and less than or equal to 500 nm.

[0015] The first thin-film electrode may cover a portion of the first surface of the laminate, and the second thin-film electrode may cover a portion of the second surface of the laminate.

[0016] The first external electrode can cover the first thin film electrode and the portion of the first surface of the laminate that is not provided with the first thin film electrode, and the second external electrode can cover the second thin film electrode and the portion of the second surface of the laminate that is not provided with the second thin film electrode.

[0017] The first external electrode may cover a portion of the fifth surface and a portion of the sixth surface of the laminate, and the second external electrode may cover another portion of the fifth surface and another portion of the sixth surface of the laminate.

[0018] The first thin-film electrode can completely cover the first surface of the laminate, and the second thin-film electrode can completely cover the second surface of the laminate.

[0019] The first external electrode may cover the first thin film electrode and a portion of the fifth surface and a portion of the sixth surface of the laminate, and the second external electrode may cover the second thin film electrode and another portion of the fifth surface and another portion of the sixth surface of the laminate.

[0020] The first thin-film electrode can completely cover the first surface of the laminate, and the second thin-film electrode can completely cover the second surface of the laminate.

[0021] The first external electrode can completely cover the first thin film electrode, and the second external electrode can completely cover the second thin film electrode.

[0022] The first thin-film electrode and the second thin-film electrode may include platinum (Pt), gold (Au), nickel (Ni), chromium (Cr), molybdenum (Mo), or combinations thereof.

[0023] The positive electrode layer may include a positive electrode current collector and a positive electrode active material layer, and the negative electrode layer may include a negative electrode active material layer.

[0024] An all-solid-state battery according to an embodiment includes: a stack comprising a first surface and a second surface opposite to each other in a first direction, a third surface and a fourth surface opposite to each other in a second direction and connecting the first surface and the second surface, and a fifth surface and a sixth surface opposite to each other in a third direction and connecting the first surface and the second surface, the stack comprising a positive electrode layer, a negative electrode layer and a solid electrolyte layer, the solid electrolyte layer being disposed between the positive electrode layer and the negative electrode layer and comprising a solid electrolyte; a first external electrode disposed at least on the first surface; a second external electrode disposed at least on the second surface; a first metal electrode disposed on the first surface to connect the positive electrode layer to the first external electrode; and a second metal electrode disposed on the second surface to connect the negative electrode layer to the second external electrode.

[0025] The metal included in the first metal electrode can extend continuously from the positive electrode layer to the first external electrode, and the metal included in the second metal electrode can extend continuously from the negative electrode layer to the second external electrode.

[0026] The thickness of the first metal electrode and the thickness of the second metal electrode may be greater than or equal to 50 nm and less than or equal to 1 μm.

[0027] The thickness of the first metal electrode and the thickness of the second metal electrode may be greater than or equal to 50 nm and less than or equal to 500 nm.

[0028] The thickness of the first metal electrode and the thickness of the second metal electrode may be greater than or equal to 200 nm and less than or equal to 1 μm.

[0029] The all-solid-state battery according to an embodiment includes: a stack comprising a first surface and a second surface opposite to each other in a first direction, a third surface and a fourth surface opposite to each other in a second direction and connecting the first surface and the second surface, and a fifth surface and a sixth surface opposite to each other in a third direction and connecting the first surface and the second surface, the stack comprising a positive electrode layer, a negative electrode layer and a solid electrolyte layer, the solid electrolyte layer being disposed between the positive electrode layer and the negative electrode layer and comprising a solid electrolyte; a first external electrode disposed at least on the first surface; a second external electrode disposed at least on the second surface; a first electrode disposed on the first surface to connect the positive electrode layer to the first external electrode and having a thickness of less than or equal to 1 μm; and a second electrode disposed on the second surface to connect the negative electrode layer to the second external electrode and having a thickness of less than or equal to 1 μm.

[0030] The thickness of the first electrode and the thickness of the second electrode may be greater than or equal to 50 nm and less than or equal to 1 μm.

[0031] The thickness of the first electrode and the thickness of the second electrode may be greater than or equal to 50 nm and less than or equal to 500 nm.

[0032] The thickness of the first electrode and the thickness of the second electrode may be greater than or equal to 200 nm and less than or equal to 1 μm.

[0033] Beneficial effects of the invention According to the embodiment of the all-solid-state battery, the electrode layer and the outer electrode are uniformly connected to ensure stable charging and discharging. Attached Figure Description

[0034] Figure 1 This is a schematic perspective view of an all-solid-state battery according to an embodiment.

[0035] Figure 2 It is shown schematically. Figure 1 A three-dimensional diagram of the stacked structure of an all-solid-state battery.

[0036] Figure 3 It is along Figure 1 The cross-sectional view taken from line III-III'.

[0037] Figure 4A schematically shows Figure 1 A partial cross-sectional view of the positive electrode layer of an all-solid-state battery.

[0038] Figure 4B schematically illustrates Figure 1 A partial cross-sectional view of the negative electrode layer of an all-solid-state battery.

[0039] Figure 5This is a scanning electron microscope image showing the result of depositing a first thin film electrode using a sputtering target of 300 nm to 400 nm.

[0040] Figure 6 This is a scanning electron microscope image showing the result of depositing a first thin film electrode using a sputtering target with a wavelength of 500 nm to 600 nm.

[0041] Figure 7 This is a scanning electron microscope image showing the result of depositing a first thin film electrode using a 1000 nm sputtering target.

[0042] Figure 8 This is a scanning electron microscope image showing the results of depositing a second thin film electrode using a sputtering target with a wavelength of 300 nm to 400 nm.

[0043] Figure 9 This is a scanning electron microscope image showing the results of depositing a second thin film electrode using a sputtering target with a wavelength of 500 nm to 600 nm.

[0044] Figure 10 This is a scanning electron microscope image showing the result of depositing a second thin film electrode using a 1000 nm sputtering target.

[0045] Figure 11 This is a schematic cross-sectional view of an all-solid-state battery according to another embodiment.

[0046] Figure 12 This is a schematic cross-sectional view of an all-solid-state battery according to another embodiment.

[0047] Figure 13A is a graph showing the results of a charge-discharge cycle test of the all-solid-state battery according to Example 1.

[0048] Figure 13B is a graph showing the results of a charge-discharge cycle test of the all-solid-state battery according to Example 2.

[0049] Figure 13C is a graph showing the results of a charge-discharge cycle test of the all-solid-state battery according to Example 3.

[0050] Figure 13D is a graph showing the results of a charge-discharge cycle test of the all-solid-state battery according to Example 4.

[0051] Figure 13E is a graph showing the results of a charge-discharge cycle test of the all-solid-state battery according to Example 5.

[0052] Figure 13F is a graph showing the results of a charge-discharge cycle test of the all-solid-state battery according to Example 6.

[0053] Figure 13G is a graph showing the results of a charge-discharge cycle test of the all-solid-state battery according to Example 7.

[0054] Figure 13H is a graph showing the results of a charge-discharge cycle test of the all-solid-state battery according to the comparative example.

[0055] Figure 14 It is a graph showing how the capacity retention varies with the thickness of the thin-film electrode of the all-solid-state battery according to the embodiment. Detailed Implementation

[0056] In the following description, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings, which will enable those skilled in the art to readily practice the invention. The drawings and description are intended to be illustrative rather than restrictive in nature. Throughout the specification, the same reference numerals denote the same elements. Furthermore, in the drawings, some components are enlarged, omitted, or shown schematically, and the dimensions of the individual components do not perfectly reflect their actual dimensions.

[0057] The accompanying drawings are provided only to facilitate understanding of the embodiments disclosed in this specification, and the technical concepts disclosed in this specification are not limited to the drawings. It should be understood that all changes, equivalents, or substitutions are included within the spirit and scope of this disclosure.

[0058] Terms containing ordinal numbers such as "first" and "second" can be used to describe various constituent elements, but the constituent elements are not limited by the term. The term is used only for the purpose of distinguishing one constituent element from another.

[0059] It will be understood that when an element such as a layer, film, region, or substrate is referred to as "on" or "above" another element, the element may be directly on the other element, or there may be an intermediate element present. In contrast, when an element is referred to as "directly on" another element, there is no intermediate element present. Furthermore, throughout this specification, the terms "on" or "above" the target element will be understood to mean located above or below the target element, and will not necessarily be understood to mean located "on top" based on a direction opposite to the direction of gravity.

[0060] Throughout this specification, terms such as “comprising” or “having” are intended to indicate the presence of the features, quantities, steps, operations, constituent elements, components, or combinations thereof described in the specification, and should be understood as not excluding the possibility of the presence or addition of one or more other features, quantities, steps, actions, constituent elements, components, or combinations thereof. Furthermore, unless expressly stated to the contrary, the words “comprising” and variations such as “including” or “having” will be understood to imply the inclusion of the stated elements but not the exclusion of any other elements.

[0061] Furthermore, throughout the instruction manual, the phrase "in a plane" refers to the target portion viewed from the top, and the phrase "in a cross section" refers to the cross section formed by vertically cutting the target portion viewed from the side.

[0062] Throughout the specification, “connection” means not only the case where two or more components are directly connected, but also the case where two or more components are indirectly connected through another component, or the case where two or more components are physically or electrically connected, and may include the case where essentially integrated parts are connected to each other, even though they are called by different names according to their location or function.

[0063] Figure 1 This is a schematic perspective view of an all-solid-state battery according to an embodiment. Figure 2 It is shown schematically. Figure 1 A three-dimensional diagram of the stacked structure of an all-solid-state battery, and Figure 3 It is along Figure 1 The cross-sectional view taken from line III-III'.

[0064] Reference Figure 1 , Figure 2 and Figure 3 The all-solid-state battery 1000 according to this embodiment includes a laminate 100, a first thin-film electrode 210, a second thin-film electrode 220, a first external electrode 300, and a second external electrode 400.

[0065] First, orientations are defined for the purpose of clearly describing this embodiment. The L-axis, W-axis, and T-axis shown in the accompanying drawings represent the length, width, and thickness directions of the all-solid-state battery 1000, respectively.

[0066] The thickness direction (T-axis direction) can be a direction perpendicular to the wide surface (main surface) of a constituent element with a sheet shape. For example, the thickness direction (T-axis direction) can be used as the same concept as the direction of stacking of laminates 100.

[0067] The length direction (L-axis direction) can be parallel to the wide surface (main surface) of the constituent element with a sheet shape, and can be a direction that intersects (or is perpendicular to) the thickness direction (T-axis direction). For example, the length direction (L-axis direction) can be the direction in which the first external electrode 300 and the second external electrode 400 are opposite to each other.

[0068] The width direction (W-axis direction) can be parallel to the wide surface (main surface) of the constituent element with a sheet shape, and can be a direction that intersects (or is perpendicular to) both the thickness direction (T-axis direction) and the length direction (L-axis direction).

[0069] The laminate 100 may have a generally hexahedral shape, but this embodiment is not limited to this. Due to shrinkage during sintering, the laminate 100 may not have a perfectly hexahedral shape, but may have a generally hexahedral shape. For example, the laminate 100 may have a generally parallelepiped shape, but the portions corresponding to corners or vertices may have a rounded shape.

[0070] For ease of description of this embodiment, surfaces that are opposite to each other in the length direction (L-axis direction) are defined as first surface S1 and second surface S2, surfaces that are opposite to each other in the width direction (W-axis direction) and connect first surface S1 and second surface S2 are defined as third surface S3 and fourth surface S4, and surfaces that are opposite to each other in the thickness direction (T-axis direction) and connect first surface S1 and second surface S2 are defined as fifth surface S5 and sixth surface S6.

[0071] Therefore, the first direction, which is the direction in which the first surface S1 and the second surface S2 are opposite to each other, can be the length direction (L-axis direction), and the second and third directions, which are perpendicular to the first direction and perpendicular to each other, can be the thickness direction (T-axis direction) and the width direction (W-axis direction), respectively, or they can be the width direction (W-axis direction) and the thickness direction (T-axis direction), respectively.

[0072] Based on optical microscopy or scanning electron microscopy (SEM) images of a cross-section (taken along the length direction (L-axis) and thickness direction (T-axis)) at the central portion of the laminate 100 in the width direction (W-axis direction), the length of the laminate 100 can be defined as the maximum length of a plurality of line segments connecting the two outermost boundary lines of the laminate 100 shown in the above images, which are opposite each other in the length direction (L-axis direction) and parallel to the length direction (L-axis direction). Furthermore, the length of the laminate 100 can be defined as the minimum length of a plurality of line segments connecting the two outermost boundary lines of the laminate 100 shown in the above images, which are opposite each other in the length direction (L-axis direction) and parallel to the length direction (L-axis direction). Additionally, the length of the laminate 100 can be defined as the arithmetic mean of the lengths of at least two line segments connecting the two outermost boundary lines of the laminate 100 shown in the above images, which are opposite each other in the length direction (L-axis direction) and parallel to the length direction (L-axis direction).

[0073] Based on optical microscope or scanning electron microscope (SEM) images of a cross-section (taken along the length direction (L-axis direction) and thickness direction (T-axis direction) at the central portion of the laminate 100 in the width direction (W-axis direction), the thickness of the laminate 100 can be defined as the maximum length of a plurality of line segments connecting the two outermost boundary lines of the laminate 100 shown in the above images, which are opposite each other in the thickness direction (T-axis direction) and parallel to the thickness direction (T-axis direction). Furthermore, the thickness of the laminate 100 can be defined as the minimum length of a plurality of line segments connecting the two outermost boundary lines of the laminate 100 shown in the above images, which are opposite each other in the thickness direction (T-axis direction) and parallel to the thickness direction (T-axis direction). Furthermore, the thickness of the laminate 100 can refer to the arithmetic mean of the lengths of at least two line segments among the multiple line segments that connect the two outermost boundary lines of the laminate 100 shown in the above photograph and are opposite to each other in the thickness direction (T-axis direction) and are parallel to the thickness direction (T-axis direction).

[0074] Based on optical microscope or scanning electron microscope (SEM) images of a cross-section (taken along the length direction (L-axis direction) and width direction (W-axis direction) at the central portion of the laminate 100 in the thickness direction (T-axis direction), the width of the laminate 100 can be defined as the maximum length of a plurality of line segments connecting the two outermost boundary lines of the laminate 100 shown in the above images, which are opposite each other in the width direction (W-axis direction) and parallel to the width direction (W-axis direction). Alternatively, the width of the laminate 100 can be defined as the minimum length of a plurality of line segments connecting the two outermost boundary lines of the laminate 100 shown in the above images, which are opposite each other in the width direction (W-axis direction) and parallel to the width direction (W-axis direction). Furthermore, the width of the stack 100 can refer to the arithmetic mean of the lengths of at least two line segments among the multiple line segments that connect the two outermost boundary lines of the stack 100 shown in the above photograph and are opposite to each other in the width direction (W-axis direction) and are parallel to the width direction (W-axis direction).

[0075] The laminate 100 may include a solid electrolyte layer 110, a positive electrode layer 130, a negative electrode layer 150, an upper protective layer 160, a lower protective layer 170, and an edge portion 180.

[0076] The laminate 100 may include multiple solid electrolyte layers 110, multiple positive electrode layers 130, and multiple negative electrode layers 150. The positive electrode layers 130 and negative electrode layers 150 may be stacked alternately in the thickness direction (T-axis direction), with the solid electrolyte layers 110 positioned between the positive electrode layers 130 and the negative electrode layers 150. This stacking structure may be repeated within the laminate 100. The electrode layer closest to the fifth surface S5 of the laminate 100 may be either the positive electrode layer 130 or the negative electrode layer 150, and the electrode layer closest to the sixth surface S6 may be either the negative electrode layer 150 or the positive electrode layer 130.

[0077] The positive electrode layer 130 may be disposed on one surface of the solid electrolyte layer 110, and the negative electrode layer 150 may be disposed on the other surface of the solid electrolyte layer 110.

[0078] The solid electrolyte layer 110 includes a solid electrolyte. The solid electrolyte can be used as a channel for lithium (Li) ions.

[0079] The solid electrolyte included in the solid electrolyte layer 110 may include a glass-ceramic-based electrolyte containing lithium halides (LiX, where X is a halogen element such as F, Br, Cl, I, etc.). Glass-ceramics (or microcrystalline glass) refer to a mixture of crystalline and amorphous materials that exhibit peaks and bulges in X-ray diffraction, electron beam diffraction, etc., and are crystallographically consistent. Therefore, glass-ceramic-based electrolytes are electrolytes that undergo partial crystallization through sintering and contain a mixture of amorphous and crystalline materials.

[0080] Glass-ceramic based electrolytes can be mixtures of amorphous materials and two or more types of crystalline materials. Furthermore, the crystalline materials contained in glass-ceramic based electrolytes can include lithium compound crystalline phases containing lithium.

[0081] When a glass-ceramic-based electrolyte is included in the solid electrolyte layer 110, sufficient densification is achieved after sintering, thereby enabling high ionic conductivity.

[0082] Glass-ceramic based electrolytes may include at least one selected from the group consisting of lithium (Li) oxide, boron (B) oxide, silicon (Si) oxide, aluminum (Al) oxide, gallium (Ga) oxide, phosphorus (P) oxide, germanium (Ge) oxide, magnesium (Mg) oxide, and lithium chloride (LiCl). As a specific example, glass-ceramic based electrolytes may include Li₂O-B₂O₃-SiO₂-P₂O₅-GeO₂-LiCl.

[0083] Optionally, the solid electrolyte included in the solid electrolyte layer 110 may include a lithium borosilicate-based electrolyte (hereinafter, also referred to as an LBSO-based electrolyte). The LBSO-based electrolyte is a glassy electrolyte, and glass refers to a crystallographically amorphous material that exhibits a hump peak in X-ray diffraction, electron beam diffraction, etc.

[0084] When the LBSO-based electrolyte is included in the solid electrolyte layer 110, it can maintain an amorphous state during sintering while reducing the sintering temperature. Therefore, it has the advantages of achieving high ionic conductivity and having low reactivity with electrodes. The LBSO-based electrolyte may include lithium (Li), boron (B), silicon (Si), aluminum (Al), phosphorus (P), germanium (Ge), and sulfur (S).

[0085] Optionally, the solid electrolyte included in the solid electrolyte layer 110 may be one or more types selected from the group consisting of garnet type, Na superionic conductor (NASICON) type, lithium superionic conductor (LISICON) type, perovskite type, and lithium phosphorus oxynitride (LiPON) type.

[0086] In some embodiments, the solid electrolyte layer 110 may include a first edge portion 181 and a second edge portion 183. The first edge portion 181 and the second edge portion 183, which will be described later, may include a material having low ionic conductivity and low electron conductivity (i.e., an insulating material), or may include a material having an ionic conductivity (or electron conductivity) approximate to that of the solid electrolyte. For example, the material having an ionic conductivity (or electron conductivity) approximate to that of the solid electrolyte included in the first edge portion 181 and the second edge portion 183 may be the same or different from the solid electrolyte in other regions. As another example, a material having an ionic conductivity (or electron conductivity) approximate to that of the solid electrolyte and an insulating material may coexist in the region.

[0087] The garnet-type solid electrolyte may refer to lithium lanthanum zirconium oxide (LLZO) represented by Li x La b Zr c O 12 (such as Li7La3Zr2O 12 ), and the NASICON-type solid electrolyte may include lithium aluminum titanium phosphate (LATP) (Li 1+x Al x M 2-x (PO4)3 (LAMP) (where 0 < x < 2, and M is Zr, Ti, or Ge) type compounds generated by introducing Ti into Li 1+x Al x Ti2-x (PO4)3) (where 0 < x < 1), lithium aluminogermanium phosphate (LAGP) and / or lithium zirconium phosphate (LZP) (LiZr2(PO4)3) containing excess lithium, represented by Li 1+x Al x Ge 2-x (PO4)3 (where 0 < x < 1) (such as Li 1.3 Al 0.3 Ge 1.7 (PO4)3).

[0088] In addition, the LISICON-type solid electrolyte may include a solid solution oxide represented by xLi3AO4-(1-x)Li4BO4 (where A is P, As, V, etc., and B is Si, Ge, Ti, etc.), such as Li4Zn(GeO4)4, Li 10 GeP2O 12 (LGPO), Li 3.5 Si 0.5 P 0.5 O4, Li 10.42 Si(Ge) 1.5 P 1.5 Cl 0.08 O 11.92 etc., and solid solution sulfides such as Li2S-P2S5, Li2S-SiS2, Li2S-SiS2-P2S5, Li2S-GeS2, etc., represented by Li 4-x M 1-y M' y S4 (where M is Si or Ge, and M' is P, Al, Zn or Ga).

[0089] In addition, the perovskite-type solid electrolyte includes lithium lanthanum titanate oxide (LLTO) represented by Li 3x La 2 / 3-x □ 1 / 3-2x TiO3 (where 0 < x < 0.16, and □ is a vacancy) (such as Li 1 / 8 La 5 / 8 TiO3). The LiPON-type solid electrolyte may refer to nitrides such as lithium phosphorus oxynitride (such as Li 2.8 PO 3.3 N 0.46 ).

[0090] The positive electrode layer 130 may be exposed to the outside of the laminate 100 from the first surface S1 of the laminate 100 and may be connected to the first thin film electrode 210.<\

[0091] Refer to Figure 3As shown in Figure 4A, the positive electrode layer 130 may include a positive electrode current collector 133, a first positive electrode active material layer 135, and a second positive electrode active material layer 136.

[0092] For example, the positive electrode current collector 133 can be made using a plate-like component or a thin component. As another example, the positive electrode current collector 133 can be a porous body having a network-like or mesh-like structure.

[0093] The positive current collector 133 may include a first surface 133a and a second surface 133b. The first surface 133a and the second surface 133b are opposite to each other in the thickness direction (T-axis direction).

[0094] For example, the positive current collector 133 may include, but is not limited to, a porous metal plate made of stainless steel, nickel (Ni), copper (Cu), tin (Sn), aluminum (Al), or alloys thereof.

[0095] In addition, the positive current collector 133 may be coated with an antioxidant metal or alloy film to prevent oxidation.

[0096] The positive electrode current collector 133 may include a carbon substrate-like component, a thin component, a linear component, or a circular component. The positive electrode current collector 133 may include a conductive carbon material. The conductive carbon material may include graphite, conductive fibers (such as carbon nanotubes (CNTs) or vapor-grown carbon fibers (VGCF)) or conductive carbon (such as carbon black).

[0097] In addition, the positive electrode current collector may also include one or more types of solid electrolytes.

[0098] The first positive electrode active material layer 135 and the second positive electrode active material layer 136 may include positive electrode active material and may be disposed on the surface of the positive electrode current collector 133. The first positive electrode active material layer 135 and the second positive electrode active material layer 136 may be formed by printing positive electrode active material on one or both surfaces of the positive electrode current collector 133. However, the method for forming the positive electrode active material layers is not limited thereto.

[0099] The positive electrode active material included in the positive electrode active material layer 135 may include a material containing lithium (Li) ions. The positive electrode active material can reversibly insert and extract lithium ions. That is, the positive electrode active material may contain lithium ions and be used to provide lithium ions to the negative electrode during charging of the all-solid-state battery. The positive electrode active material can affect the capacity and output of the all-solid-state battery.

[0100] For example, positive electrode active materials may include at least one selected from the group consisting of compounds represented by the following chemical formulas: Li a A 1-b M b D2 (where 0.90≤a≤1.8 and 0≤b≤0.5); Lia E 1-b M b O 2-c D c (Where, 0.90≤a≤1.8, 0≤b≤0.5, and 0≤c≤0.05); LiE 2-b M b O 4-c D c (Where, 0 ≤ b ≤ 0.5, and 0 ≤ c ≤ 0.05); Li a Ni 1-b- c Co b M c D α (Where, 0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.05, and 0<α≤2); Li a Ni 1-b-c Co b M c O 2-α X α (Where, 0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.05, and 0<α<2); Li a Ni 1-b-c Co b M c O 2-α X2 (where 0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.05, and 0<α<2); Li a Ni 1-b-c Mn b M c D α (Where, 0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.05, and 0<α≤2); Li a Ni 1-b-c Mn b M c O 2-α X α (Where, 0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.05, and 0<α<2); Li a Ni 1-b-c Mn b M c O 2-α X2 (where 0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.05, and 0<α<2); Li a Ni b E c G dO2 (where 0.90≤a≤1.8, 0≤b≤0.9, 0≤c≤0.5, and 0.001≤d≤0.1); Li a Ni b Co c Mn d G e O2 (where 0.90≤a≤1.8, 0≤b≤0.9, 0≤c≤0.5, 0≤d≤0.5, and 0.001≤e≤0.1); Li a NiG b O2 (where 0.90 ≤ a ≤ 1.8 and 0.001 ≤ b ≤ 0.1); Li a CoG b O2 (where 0.90 ≤ a ≤ 1.8 and 0.001 ≤ b ≤ 0.1); Li a MnG b O2 (where 0.90 ≤ a ≤ 1.8 and 0.001 ≤ b ≤ 0.1); Li a Mn2G b O4 (where 0.90≤a≤1.8 and 0.001≤b≤0.1); QO2; QS2; LiQS2; V2O5; LiV2O2; LiRO2; LiNiVO4; Li (3-f) J2(PO4)3 (where 0≤f≤2); Li (3-f) Fe2(PO4)3 (where 0≤f≤2) and LiFePO4. In the above chemical formulas, A represents Ni, Co, or Mn; M represents Al, Ni, Co, Mn, Cr, Fe, Mg, Sr, V, Nb, Ti, or rare earth elements; D represents O, F, S, or P; E represents Co or Mn; X represents F, S, or P; G represents Al, Cr, Mn, Fe, Mg, La, Ce, Sr, or V; Q represents Ti, Mo, or Mn; R represents Cr, V, Fe, Sc, or Y; and J represents V, Cr, Mn, Co, Ni, or Cu.

[0101] Positive electrode active materials may also include LiCoO2 and LiMn. x O 2x (where x is 1 or 2), LiNi 1-x Mn x O 2x (where 0) <x<1)、LiNi 1-x-y Co x Mn y O2 (where 0 ≤ x ≤ 0.5 and 0 ≤ y ≤ 0.5), LiFePO4, TiS2, FeS2, TiS3 or FeS3, but this disclosure is not limited thereto.

[0102] The positive electrode active material may selectively include conductive materials and binders. However, because organic materials such as binders decompose during the sintering process, organic materials may not remain on the positive electrode active material layer of the final positive electrode current collector.

[0103] There are no particular restrictions on the conductive materials, as long as they are conductive and do not cause chemical changes in the all-solid-state battery 1000. For example, the following materials can be used: graphite, such as natural and artificial graphite; carbon-based materials, such as carbon black (acetylene black, Ketjen black). ® Carbon black produced by channel black, furnace black, lamp black, and pyrolysis black; conductive fibers, such as carbon fibers and metal fibers; fluorides; metallic components (such as lithium (Li), tin (Sn), aluminum (Al), nickel (Ni), copper (Cu), etc.), oxides of metallic components, nitrides of metallic components, or fluorides of metallic components; conductive whiskers, such as zinc oxide or potassium titanate; conductive metal oxides, such as titanium oxide; and conductive materials, such as polyphenylene derivatives.

[0104] Adhesives can be used to improve the bonding strength of active materials, conductive materials, etc. Adhesives may include, but are not limited to, at least one selected from the group consisting of polyvinylidene fluoride, polyvinyl alcohol, carboxymethyl cellulose (CMC), starch, hydroxypropyl cellulose, regenerated cellulose, polyvinylpyrrolidone, polytetrafluoroethylene, polyethylene, polypropylene, ethylene propylene diene monomer (EPDM), sulfonated EPDM, styrene-butadiene rubber (SBR), fluororubber, and various copolymers.

[0105] Furthermore, the positive electrode layer 130 may also contain a solid electrolyte component. The solid electrolyte component may contain one or more of the components mentioned above and can serve as an ion conduction channel in the positive electrode layer. Therefore, the interfacial resistance can be reduced.

[0106] The negative electrode layer 150 may be exposed to the outside of the laminate 100 from the second surface S2 of the laminate 100 and may be connected to the second external electrode 400.

[0107] Reference Figure 3 As shown in Figure 4B, the negative electrode layer 150 may include a negative electrode current collector 153, a first negative electrode active material layer 155, and a second negative electrode active material layer 156.

[0108] For example, the negative electrode current collector 153 may include a plate-like member or a thin member. As another example, the negative electrode current collector 153 may include a porous body having a network-like, mesh-like, or similar structure.

[0109] The negative electrode current collector 153 may include a first surface 153a and a second surface 153b. The first surface 153a and the second surface 153b are opposite to each other in the thickness direction (T-axis direction).

[0110] For example, the negative electrode current collector 153 may include, but is not limited to, a porous metal plate made of, for example, stainless steel, nickel (Ni), copper (Cu), tin (Sn), aluminum (Al), or an alloy thereof.

[0111] In addition, the negative electrode current collector 153 may be coated with an oxidation-resistant metal or alloy film to prevent oxidation.

[0112] The negative electrode current collector 153, similar to the positive electrode current collector 133, may include a conductive carbon-based material and may include one or more types of solid electrolytes. The negative electrode current collector 153 may be the same as the negative electrode active material layers 155 and 156.

[0113] The first negative electrode active material layer 155 and the second negative electrode active material layer 156 may include a negative electrode active material and may be provided on the surface of the negative electrode current collector 153. The negative electrode active material layer 155 may be formed by printing the negative electrode active material on one or both surfaces of the negative electrode current collector 153. However, the method of forming the negative electrode active material layer is not limited thereto.

[0114] The negative electrode active material in the negative electrode active material layer 155 may store lithium ions moving from the positive electrode and release lithium ions during discharge of the all-solid-state battery, thereby generating electric energy. A carbon-based material, silicon, silicon oxide, silicon-based alloy, silicon-carbon-based material composite, tin, tin-based alloy, tin-carbon composite, metal oxide, or a combination thereof may be used as the negative electrode active material. The negative electrode active material may contain lithium metal and / or a lithium metal alloy.

[0115] The lithium metal alloy may contain lithium and a metal / metalloid capable of alloying with lithium. For example, the metal / metalloid capable of alloying with lithium may be Si, Sn, Al, Ge, Pb, Bi, Sb, Si-AM alloy (where AM is an alkali metal, alkaline earth metal, element in Groups 13 to 16, transition metal, rare earth element, or a combination thereof, and does not include Si), Sn-AM alloy (where AM is an alkali metal, alkaline earth metal, element in Groups 13 to 16, transition metal, transition metal oxide such as lithium titanate (Li4Ti5O 12 ), rare earth element, or a combination thereof, and does not include Sn), MnO x (where 0 < x ≤ 2), etc.

[0116] The element AM may include 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, or a combination thereof.

[0117] In addition, the oxides of metals / metalloids capable of alloying with lithium may include lithium titanium oxide, vanadium oxide, lithium vanadium oxide, SnO2, SiO x (where 0 < x < 2). For example, the negative electrode active material may include one or more elements selected from the group consisting of elements in Groups 13 to 16 of the periodic table. For example, the negative electrode active material may include one or more elements selected from the group consisting of Si, Ge, and Sn.

[0118] The carbon-based material may include crystalline carbon, amorphous carbon, or a mixture thereof. The crystalline carbon may be graphite, such as natural graphite or artificial graphite in an amorphous form, disk form, flake form, spherical form, or fiber form. In addition, the amorphous carbon may include, but is not limited to, soft carbon (low-temperature calcined carbon), hard carbon, mesophase pitch carbide, calcined coke, graphene, carbon black, fullerene soot, carbon nanotubes, carbon fibers, etc.

[0119] Silicon may include at least one selected from the group consisting of Si, SiO x (where 0 < x < 2, for example, 0.5 to 1.5), Sn, SnO2, or a silicon-containing metal alloy and their mixtures. For example, the silicon-containing metal alloy may include one or more of Al, Sn, Ag, Fe, Bi, Mg, Zn, In, Ge, Pb, or Ti and silicon.

[0120] The negative electrode active material may selectively include a conductive material and an adhesive.

[0121] The conductive material is not particularly limited as long as it has conductivity and does not cause chemical changes in the all-solid-state battery 1000. For example, the following materials may be used: graphite, such as natural graphite and artificial graphite; carbon-based materials, such as carbon black (acetylene black, Ketjen black ® , channel black, furnace black, lamp black, and thermal cracking carbon black); conductive fibers, such as carbon fibers, metal fibers, etc.; carbon fluorides; metal components (such as lithium (Li), tin (Sn), aluminum (Al), nickel (Ni), copper (Cu), etc.), oxides of metal components, nitrides of metal components, or fluorides of metal components; conductive whiskers, such as zinc oxide or potassium titanate; conductive metal oxides, such as titanium oxide; or conductive materials, such as polyphenylene derivatives, etc.

[0122] Adhesives can be used to improve the bonding strength of active materials, conductive materials, etc. Adhesives may include, but are not limited to, at least one selected from the group consisting of polyvinylidene fluoride, polyvinyl alcohol, carboxymethyl cellulose (CMC), starch, hydroxypropyl cellulose, regenerated cellulose, polyvinylpyrrolidone, polytetrafluoroethylene, polyethylene, polypropylene, ethylene propylene diene monomer (EPDM), sulfonated EPDM, styrene-butadiene rubber (SBR), fluororubber, and various copolymers.

[0123] The upper protective layer 160 and the lower protective layer 170 can be the outermost layers respectively disposed on the fifth surface S5 and the sixth surface S6 of the laminate 100. That is, the upper protective layer 160 can be the outermost layer located on the fifth surface S5 of the laminate 100, and the lower protective layer 170 can be the outermost layer located on the sixth surface S6 of the laminate 100. The upper protective layer 160 and the lower protective layer 170 can improve moisture-proof reliability by preventing moisture penetration and can prevent damage caused by physical stress and chemical stress.

[0124] The upper protective layer 160 and the lower protective layer 170 may be insulating layers comprising an insulating material (i.e., a non-conductive (ionic) material).

[0125] The upper protective layer 160 and the lower protective layer 170 may include, but are not limited to, at least one ceramic material selected from, for example, alumina (Al2O3), aluminum nitride (AlN), beryllium oxide (BeO), boron nitride (BN), silicon (Si), silicon carbide (SiC), silicon dioxide (SiO2), silicon nitride (Si3N4), gallium arsenide (GaAs), gallium nitride (GaN), barium titanate (BaTiO3), zirconium dioxide (ZrO2), mixtures thereof, oxides and / or nitrides of these materials, and any other suitable ceramic material. Additionally, the upper protective layer 160 and the lower protective layer 170 may selectively include the aforementioned solid electrolyte and may include one or more types of solid electrolytes. However, this disclosure is not limited thereto.

[0126] For example, the edge portion 180 may be provided on the solid electrolyte layer 110 and located in a region other than the region where the positive electrode layer 130 or the negative electrode layer 150 is provided. If a positive electrode layer 130 is provided on the solid electrolyte layer 110, the edge portion 180 may be provided in a region other than the region where the positive electrode layer 130 is provided. Similarly, if a negative electrode layer 150 is provided on the solid electrolyte layer 110, the edge portion 180 may be provided in a region other than the region where the negative electrode layer 150 is provided.

[0127] Reference Figure 3Edge portion 180 may form part of the first surface S1 and part of the second surface S2 of the laminate 100. For example, first edge portion 181 may form part of the second surface S2 of the laminate 100, and second edge portion 183 may form part of the first surface S1 of the laminate 100. On the other hand, although not shown in the figures, edge portion 180 may form part of the third surface S3 and part of the fourth surface S4 of the laminate 100.

[0128] The edge portion 180 can be configured to compensate for the height difference between the solid electrolyte layer 110 and the positive electrode layer 130, and the height difference between the solid electrolyte layer 110 and the negative electrode layer 150. For example, the edge portion 180 can be disposed on the same surface as the surface of the positive electrode layer 130 and the same surface as the surface of the negative electrode layer 150. The edge portion 180 can compensate for the height difference between the solid electrolyte layer 110 and the positive electrode layer 130, or the height difference between the solid electrolyte layer 110 and the negative electrode layer 150. This increases the density between the solid electrolyte layer 110 and the electrode layers, preventing interlayer delamination or warping caused by sintering during the manufacturing process of all-solid-state batteries.

[0129] The edge portion 180 may include an insulating material (i.e., a non-conductive (ionic) material).

[0130] The edge portion 180 may include, but is not limited to, at least one ceramic material selected from, for example, alumina (Al2O3), aluminum nitride (AlN), beryllium oxide (BeO), boron nitride (BN), silicon (Si), silicon carbide (SiC), silicon dioxide (SiO2), silicon nitride (Si3N4), gallium arsenide (GaAs), gallium nitride (GaN), barium titanate (BaTiO3), zirconium dioxide (ZrO2), mixtures thereof, oxides thereof and / or nitrides thereof, and any other suitable ceramic material.

[0131] Furthermore, the edge portion 180 may selectively contain the aforementioned solid electrolyte, and may include one or more types of solid electrolytes. However, this disclosure is not limited thereto.

[0132] Additionally, in the edge portion 180, a material with low ionic conductivity and low electronic conductivity (i.e., an insulating material) may be present, and a material with ionic conductivity (or electronic conductivity) approximating that of the solid electrolyte may also be present. For example, when a material with ionic conductivity (or electronic conductivity) approximating that of the solid electrolyte is present in the edge portion, this material may be the same as or different from the solid electrolyte in other regions. As another example, a material with ionic conductivity (or electronic conductivity) approximating that of the solid electrolyte and an insulating material may coexist in the edge portion.

[0133] The first thin-film electrode 210 and the second thin-film electrode 220 are disposed on the outer surface of the laminate 100.

[0134] The first thin-film electrode 210 is directly connected to the positive electrode layer 130 and the solid electrolyte layer 110 on the first surface S1 of the laminate 100. For example, the first thin-film electrode 210 may cover the first surface S1 of the laminate 100.

[0135] The first thin-film electrode 210 is a deposited atomic layer, rather than a sintered electrode using conductive paste, and can be formed using thin-film formation methods such as plating, sputtering, vacuum evaporation, and chemical vapor deposition (CVD). In other words, the first thin-film electrode is an electrode formed by uniformly depositing atoms (i.e., a metal electrode), thus having a uniform thickness and containing fine grains with sizes ranging from tens to hundreds of nanometers (nm). On the other hand, a sintered electrode has individual particles with sizes ranging from several micrometers (μm) to tens of micrometers (μm) or particles with some interconnected structures. Furthermore, the microstructure of a thin-film electrode formed by vapor deposition without the use of organic materials (such as binders) can be distinguished from that of a sintered electrode by the presence or absence of organic materials. Using thin-film formation methods, a thin-film electrode of desired thickness can be formed while suppressing thickness variations, resulting in a thin and uniform thin-film electrode. For example, the first thin-film electrode 210 can be a sputtered electrode.

[0136] Electrodes formed by methods other than the thin film deposition method described above (such as paste impregnation) may not have a uniform thickness.

[0137] The thickness of the first thin-film electrode 210 can be greater than or equal to 50 nm and less than or equal to 1 μm. If the thickness of the first thin-film electrode 210 is less than 50 nm, the connectivity between the positive electrode layer 130 and the first external electrode 300 may be low, which may not effectively improve the charge / discharge characteristics. If the thickness of the first thin-film electrode 210 exceeds 1 μm, the time and cost of forming the thin-film electrode may increase, resulting in a decrease in yield.

[0138] Furthermore, the thickness of the first thin film electrode 210 can be greater than or equal to 50 nm and less than or equal to 500 nm, and if the thickness of the first thin film electrode 210 is greater than or equal to 500 nm, the improvement effect of the charging / discharging characteristics may reach saturation.

[0139] Here, the thickness of the thin-film electrode can refer to the average thickness. The average thickness of the thin-film electrode can be: the arithmetic mean of the values ​​measured at five evenly spaced points in the thickness direction (T-axis direction) of a thin-film electrode in the cross-section of the laminate 100 at a magnification of 20000, based on the cross-section at the center of the width direction (W-axis direction) and the length direction (L-axis direction) - thickness direction (T-axis direction) shown in the cross-sectional image.

[0140] Figure 5 This is a scanning electron microscope image showing the result of depositing a first thin film electrode using a sputtering target with a wavelength of 300 nm to 400 nm.

[0141] Reference Figure 5 The thicknesses measured at five points on the first thin-film electrode 210 are 202.3 nm, 377.7 nm, 283.3 nm, 364.2 nm, and 269.8 nm, respectively. Since the arithmetic mean of these values ​​is 299.5 nm, the thickness of the first thin-film electrode 210 can be 299.5 nm.

[0142] Figure 6 This is a scanning electron microscope image showing the result of depositing a first thin film electrode using a sputtering target with a wavelength of 500 nm to 600 nm.

[0143] Reference Figure 6 The thicknesses measured at five points on the first thin-film electrode 210 are 741.9 nm, 634.0 nm, 647.5 nm, 795.9 nm, and 607.0 nm, respectively. Since the arithmetic mean of these values ​​is 685.3 nm, the thickness of the first thin-film electrode 210 can be 685.3 nm.

[0144] Figure 7 This is a scanning electron microscope image showing the result of depositing a first thin film electrode using a 1000 nm sputtering target.

[0145] Reference Figure 7 The thicknesses measured at five points on the first thin-film electrode 210 are 849.8 nm, 1025 nm, 741.9 nm, 822.9 nm, and 809.4 nm, respectively. Since the arithmetic mean of these values ​​is 849.8 nm, the thickness of the first thin-film electrode 210 can be 849.8 nm.

[0146] The first thin-film electrode 210 may include platinum (Pt), gold (Au), nickel (Ni), chromium (Cr), molybdenum (Mo), or a combination thereof.

[0147] The second thin-film electrode 220 is directly connected to the negative electrode layer 150 and the solid electrolyte layer 110 on the second surface S2 of the laminate 100. For example, the second thin-film electrode 220 may cover the second surface S2 of the laminate 100.

[0148] The second thin-film electrode 220 is a deposited atomic layer, rather than a sintered electrode using conductive paste, and the second thin-film electrode 220 can be formed using thin-film formation methods such as plating, sputtering, vacuum evaporation, and chemical vapor deposition (CVD). Using thin-film formation methods, thin and uniform thin-film electrodes can be formed. For example, the second thin-film electrode 220 can be a sputtered electrode.

[0149] The thickness of the second thin-film electrode 220 can be greater than or equal to 50 nm and less than or equal to 1 μm. Furthermore, the thickness of the second thin-film electrode 220 can be greater than or equal to 50 nm and less than or equal to 500 nm. If the thickness of the second thin-film electrode 220 is less than 50 nm, the connectivity between the negative electrode layer 150 and the second external electrode 400 may be low, which may not effectively improve the charge / discharge characteristics. If the thickness of the second thin-film electrode 220 exceeds 1 μm, the time and cost of forming the thin-film electrode may increase, resulting in a decrease in yield.

[0150] Furthermore, the thickness of the second thin film electrode 220 can be greater than or equal to 50 nm and less than or equal to 500 nm, and if the thickness of the second thin film electrode 220 is greater than or equal to 500 nm, the improvement effect of the charging / discharging characteristics may reach saturation.

[0151] Here, the thickness of the thin-film electrode can refer to the average thickness. The average thickness of the thin-film electrode can be: the arithmetic mean of the values ​​measured at five evenly spaced points in the thickness direction (T-axis direction) of a thin-film electrode in the cross-section of the laminate 100 at a magnification of 20000, based on the cross-section at the center of the width direction (W-axis direction) and the length direction (L-axis direction) - thickness direction (T-axis direction) shown in the cross-sectional image.

[0152] Figure 8 This is a scanning electron microscope image showing the results of depositing a second thin film electrode using a sputtering target with a wavelength of 300 nm to 400 nm.

[0153] Reference Figure 8 The thicknesses measured at five points on the second thin-film electrode 220 were 256.3 nm, 418.2 nm, 364.2 nm, 391.2 nm, and 445.2 nm, respectively. Since the arithmetic mean of these values ​​is 375 nm, the thickness of the second thin-film electrode 220 can be 375 nm.

[0154] Figure 9This is a scanning electron microscope image showing the results of depositing a second thin film electrode using a sputtering target with a wavelength of 500 nm to 600 nm.

[0155] Reference Figure 9 The thicknesses measured at five points on the second thin-film electrode 220 were 593.5 nm, 701.5 nm, 809.4 nm, 364.2 nm, and 930.8 nm, respectively. Since the arithmetic mean of these values ​​is 679.9 nm, the thickness of the second thin-film electrode 220 can be 679.9 nm.

[0156] Figure 10 This is a scanning electron microscope image showing the result of depositing a second thin film electrode using a 1000 nm sputtering target.

[0157] Reference Figure 10 The thicknesses measured at five points on the second thin-film electrode 220 were 1389 nm, 998.2 nm, 1012 nm, 1079 nm, and 1187 nm, respectively. Since the arithmetic mean of these values ​​is 1133 nm, the thickness of the second thin-film electrode 220 can be 1133 nm.

[0158] Additionally, the second thin-film electrode 220 may include platinum (Pt), gold (Au), nickel (Ni), chromium (Cr), molybdenum (Mo), or combinations thereof.

[0159] The first external electrode 300 and the second external electrode 400 are disposed on the outside of the laminate 100.

[0160] The first external electrode 300 is connected to the first thin film electrode 210 on the first surface S1 of the laminate 100.

[0161] For example, the first external electrode 300 may extend onto the third surface S3, the fourth surface S4, the fifth surface S5 and the sixth surface S6 of the laminate 100 and partially cover the respective surfaces.

[0162] The second external electrode 400 is connected to the second thin film electrode 220 on the second surface S2 of the laminate 100.

[0163] For example, the second external electrode 400 may extend onto the third surface S3, the fourth surface S4, the fifth surface S5 and the sixth surface S6 of the laminate 100 and partially cover the respective surfaces.

[0164] Furthermore, in some embodiments, the first external electrode 300 and the second external electrode 400 may extend to one of the fifth surface S5 and the sixth surface S6 and partially cover the corresponding surface.

[0165] For example, the first external electrode 300 and the second external electrode 400 can be sintered electrodes comprising a conductive metal and glass. As another example, the first external electrode 300 and the second external electrode 400 can be resin-based electrodes comprising a conductive metal and a matrix resin, in which case the matrix resin can be epoxy resin.

[0166] For example, the first external electrode 300 and the second external electrode 400 may be formed by coating a paste comprising a conductive metal onto the first surface S1 and the second surface S2 of the laminate 100, respectively, or by transferring a dry film of the conductive paste onto the laminate 100 and then firing the transfer film. However, the method for forming the first external electrode 300 and the second external electrode 400 is not limited thereto. Furthermore, the conductive metal may include, for example, copper (Cu), nickel (Ni), tin (Sn), palladium (Pd), platinum (Pt), gold (Au), silver (Ag), tungsten (W), titanium (Ti), lead (Pb), or alloys thereof, but this disclosure is not limited thereto.

[0167] On the other hand, by forming plating layers on the first external electrode 300 and the second external electrode 400 respectively, the mounting characteristics of the external electrodes can also be improved. The plating layer may include at least one selected from the group consisting of copper (Cu), nickel (Ni), tin (Sn), palladium (Pd), platinum (Pt), gold (Au), silver (Ag), tungsten (W), titanium (Ti), lead (Pb), and alloys thereof, but this disclosure is not limited thereto. The plating layer may be formed in one or more layers.

[0168] As described above, according to this embodiment, the first thin-film electrode 210 and the second thin-film electrode 220 are formed thinly and uniformly using a thin-film deposition method. The first thin-film electrode 210 formed in this manner can have a uniform interface with the first external electrode 300, and the formed second thin-film electrode 220 can have a uniform interface with the second external electrode 400. Therefore, there is good connectivity between the first thin-film electrode 210 and the first external electrode 300, and good connectivity between the second thin-film electrode 220 and the second external electrode 400. In other words, the presence of the first thin-film electrode 210 allows current to flow reliably between the positive electrode layer 130 and the first external electrode 300, and the presence of the second thin-film electrode 220 allows current to flow reliably between the negative electrode layer 150 and the second external electrode 400. Therefore, the all-solid-state battery according to this embodiment can be stably charged and discharged.

[0169] Figure 11 This is a schematic cross-sectional view of an all-solid-state battery according to another embodiment.

[0170] Reference Figure 11 The all-solid-state battery 2000 includes a stack 100, a first thin-film electrode 1210, a second thin-film electrode 1220, a first external electrode 300, and a second external electrode 400.

[0171] The first thin-film electrode 1210 is connected to the positive electrode layer 130 on the first surface S1 of the laminate 100.

[0172] The first thin-film electrode 1210 covers a portion of the first surface S1 of the laminate 100.

[0173] For example, the first thin-film electrode 1210 may cover the region corresponding to the region of the first surface S1 of the laminate 100 (corresponding to the region from the electrode layer closest to the upper protective layer 160 to the electrode layer closest to the lower protective layer 170).

[0174] In other words, the first thin-film electrode 1210 may not cover the area on the first surface S1 of the laminate 100 corresponding to the area where no electrode layer is disposed. In this case, the first thin-film electrode 1210 may not cover the area between the electrode layer closest to the upper protective layer 160 and the fifth surface S5 of the laminate 100, and may not cover the area between the electrode layer closest to the lower protective layer 170 and the sixth surface S6 of the laminate 100.

[0175] The second thin-film electrode 1220 is connected to the negative electrode layer 150 on the second surface S2 of the laminate 100.

[0176] The second thin-film electrode 1220 covers a portion of the second surface S2 of the laminate 100.

[0177] For example, the second thin-film electrode 1220 may cover the region corresponding to the region of the second surface S2 of the laminate 100 (corresponding to the region from the electrode layer closest to the upper protective layer 160 to the electrode layer closest to the lower protective layer 170).

[0178] In other words, the second thin-film electrode 1220 may not cover the area on the second surface S2 of the laminate 100 corresponding to the area where no electrode layer is provided. In this case, the second thin-film electrode 1220 may not cover the area between the electrode layer closest to the upper protective layer 160 and the fifth surface S5 of the laminate 100, and may not cover the area between the electrode layer closest to the lower protective layer 170 and the sixth surface S6 of the laminate 100.

[0179] The first external electrode 300 is connected to the first thin-film electrode 1210 on the first surface S1 of the laminate 100. The first external electrode 300 can cover the first thin-film electrode 1210 and can also cover the portion of the first surface S1 of the laminate 100 where the first thin-film electrode 1210 is not disposed. That is, the first external electrode 300 can cover the area between the electrode layer closest to the upper protective layer 160 and the fifth surface S5 of the laminate 100, and can also cover the area between the electrode layer closest to the lower protective layer 170 and the sixth surface S6 of the laminate 100.

[0180] The second external electrode 400 is connected to the second thin-film electrode 1220 on the first surface S1 of the laminate 100. The second external electrode 400 can cover the second thin-film electrode 1220, and can also cover the portion of the first surface S1 of the laminate 100 where the second thin-film electrode 1220 is not disposed. That is, the second external electrode 400 can cover the region between the electrode layer closest to the upper protective layer 160 and the fifth surface S5 of the laminate 100, and can also cover the region between the electrode layer closest to the lower protective layer 170 and the sixth surface S6 of the laminate 100.

[0181] In this way, when the first thin film electrode 1210 is disposed on a portion of the first surface S1 of the laminate 100 and the second thin film electrode 1220 is disposed on a portion of the second surface S2 of the laminate 100, thin film electrodes of various shapes can be obtained.

[0182] Because the other components besides the ones mentioned above are... Figure 1 The remaining components of the all-solid-state battery shown are identical, so redundant descriptions will be omitted.

[0183] Figure 12 This is a schematic cross-sectional view of an all-solid-state battery according to another embodiment.

[0184] Reference Figure 12 The all-solid-state battery 3000 includes a stack 100, a first thin-film electrode 2210, a second thin-film electrode 2220, a first external electrode 300, and a second external electrode 400.

[0185] The first thin-film electrode 2210 is connected to the positive electrode layer 130 on the first surface S1 of the laminate 100. The first thin-film electrode 2210 covers the first surface S1 of the laminate 100 as well as a portion of the fifth surface S5 and a portion of the sixth surface S6 of the laminate 100. In addition, the first thin-film electrode 2210 may cover a portion of the third surface S3 and a portion of the fourth surface S4 of the laminate 100.

[0186] The second thin-film electrode 2220 is connected to the negative electrode layer 150 on the second surface S2 of the laminate 100. The second thin-film electrode 2220 covers the second surface S2 of the laminate 100 as well as a portion of the fifth surface S5 and a portion of the sixth surface S6 of the laminate 100. In addition, the second thin-film electrode 2220 may cover a portion of the third surface S3 and a portion of the fourth surface S4 of the laminate 100.

[0187] The first external electrode 300 can completely cover the first thin film electrode 2210. Therefore, the first external electrode 300 can be connected to the first thin film electrode 2210 on the first surface S1, the fifth surface S5, and the sixth surface S6 of the laminate 100. In addition, the first external electrode 300 can be connected to the first thin film electrode 2210 on the third surface S3 and the fourth surface S4 of the laminate 100.

[0188] The second external electrode 400 can completely cover the second thin film electrode 2220. Therefore, the second external electrode 400 can be connected to the second thin film electrode 2220 on the second surface S2, fifth surface S5, and sixth surface S6 of the laminate 100. In addition, the second external electrode 400 can be connected to the second thin film electrode 2220 on the third surface S3 and fourth surface S4 of the laminate 100.

[0189] In this way, if the first thin-film electrode 1210 is disposed not only on the first surface S1 of the laminate 100 but also on the fifth surface S5 and the sixth surface S6, and the second thin-film electrode 1220 is disposed not only on the second surface S2 of the laminate 100 but also on the fifth surface S5 and the sixth surface S6, the connectivity with the external electrode can be improved and moisture penetration can be prevented. The interface between the external electrode and the laminate may be susceptible to moisture penetration, and by placing dense thin-film electrodes not only on the first and second surfaces of the laminate but also on the fifth and sixth surfaces, the connectivity with the external electrode is enhanced, and it also acts as a barrier layer to prevent moisture penetration, thereby improving the moisture-proof performance.

[0190] Because the other components besides the ones mentioned above are... Figure 1 The rest of the components are the same as those of the all-solid-state battery, so redundant descriptions will be omitted.

[0191] Specific embodiments of the present disclosure are presented below. However, the embodiments described below are intended to illustrate or describe the present disclosure only and should not be construed as limiting the scope of the disclosure.

[0192] [Manufacturing Example: Manufacturing of All-Solid-State Batteries] (Example 1) Multiple strip-shaped positive electrode layers are printed on a solid electrolyte layer (green sheet) in the order of positive electrode active material layer, positive electrode current collector, and positive electrode active material layer. Then, the space between the positive electrode layers is filled with insulating material to form a positive electrode sheet.

[0193] Multiple strip-shaped negative electrode layers are printed on a solid electrolyte layer (green sheet) in the order of negative electrode active material layer, negative electrode current collector, and negative electrode active material layer. Then, the space between the negative electrode layers is filled with insulating material to form a negative electrode sheet.

[0194] Positive and negative electrode sheets are stacked alternately to form green sheets.

[0195] Cut the green blanks to form a laminate.

[0196] The laminate is fired at 400°C to 550°C in an air or nitrogen atmosphere.

[0197] A first platinum (Pt) thin film electrode and a second platinum (Pt) thin film electrode with a thickness of 30 nm were formed on the surface of the laminate by sputtering.

[0198] All-solid-state batteries are prepared by applying a conductive paste for the first external electrode to the surface of a first platinum (Pt) thin film electrode and a laminate, applying a conductive paste for the second external electrode to the surface of a second platinum (Pt) thin film electrode and a laminate, and then cooling to form the first and second external electrodes.

[0199] (Example 2) Example 2 is the same as Example 1, except that a first platinum (Pt) thin film electrode and a second platinum (Pt) thin film electrode with a thickness of 50 nm are formed in Example 2.

[0200] (Example 3) Example 3 is the same as Example 1, except that a first platinum (Pt) thin film electrode and a second platinum (Pt) thin film electrode with a thickness of 100 nm are formed in Example 3.

[0201] (Example 4) Example 4 is the same as Example 1, except that a first platinum (Pt) thin film electrode and a second platinum (Pt) thin film electrode with a thickness of 200 nm are formed in Example 4.

[0202] (Example 5) Example 5 is the same as Example 1, except that a first platinum (Pt) thin film electrode and a second platinum (Pt) thin film electrode with a thickness of 300 nm are formed in Example 5.

[0203] (Example 6) Example 6 is the same as Example 1, except that a first platinum (Pt) thin film electrode and a second platinum (Pt) thin film electrode with a thickness of 500 nm are formed in Example 6.

[0204] (Example 7) Example 7 is the same as Example 1, except that a first platinum (Pt) thin film electrode and a second platinum (Pt) thin film electrode with a thickness of 1000 nm (1 μm) are formed in Example 7.

[0205] (Comparative example) The comparative example is the same as Example 1, except that no first platinum (Pt) thin film electrode and a second platinum (Pt) thin film electrode are formed in the comparative example.

[0206] [Experimental Example: Performance of All-Solid-State Batteries] Five all-solid-state batteries were manufactured for each of Examples 1 to 7 and the Comparative Examples. Repeated charge / discharge cycle tests were performed on one representative sample from each of the five all-solid-state batteries. The test conditions are as follows.

[0207] At room temperature of 25°C, the charging / discharging current is 300μA, the charging voltage cutoff (or charging voltage cut-off) is 3.95V, the discharging voltage cutoff (or discharging voltage cut-off) is 2.0V, and the number of charging / discharging cycles is 30.

[0208] The test results are shown in Table 1, Figures 13A to 13H, and Figure 14 middle.

[0209] (Table 1) Cyclic numbering Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Comparative example 1 100 100 100 100 100 100 100 100 2 92.0279069 99.607199 98.87494 100.6207 99.3202 99.80157 102.5438 95.77997 3 84.4024356 96.99103 91.00072 100.3672 98.53563 99.40101 100.4174 85.662194 4 79.1759085 95.274282 99.6786 99.91264 97.82091 98.83163 99.31255 69.509069 5 74.6930161 93.436207 99.74218 99.45408 97.08873 98.3788 98.16608 53.345242 6 70.8732173 90.499889 100 98.85899 96.35655 97.87324 98.01824 41.199374 7 66.9241733 89.75473 99.92466 98.22586 95.62437 97.63321 97.32833 31.832799 8 61.3147597 87.801866 99.8377 97.45154 94.89218 97.04467 96.63842 25.88256 9 56.7654525 85.776108 98.385 96.63644 94.16 96.4093 95.94851 22.801137 10 52.6475252 83.778927 98.38587 96.18143 93.42782 95.92684 95.2586 19.012563 11 49.4813322 82.312342 96.93419 95.36472 92.69564 95.43632 94.56869 17.42054 12 46.2565255 80.261157 95.84499 94.53656 91.96345 94.81968 93.87878 15.26867 13 43.6688791 78.664284 92.57783 94.05962 91.23127 94.19172 93.18887 13.95994 14 41.0337935 76.718927 87.12472 93.22663 90.49909 93.56898 92.49897 13.084129 15 38.463436 75.325962 79.39465 92.39235 89.7669 92.63128 91.80906 12.195797 16 36.1220514 73.985789 76.74881 91.56049 89.03472 92.00898 91.11915 10.968103 17 34.2698169 72.053026 74.82692 91.04583 88.30254 90.98634 90.42924 10.422614 18 32.4338171 70.295593 72.94569 90.21381 87.57036 90.34421 89.73933 9.7588157 19 30.6096245 69.322552 71.79087 89.37115 86.83817 89.69948 89.04942 9.2815512 20 28.8900087 67.918204 70.19068 88.51366 86.10599 89.05409 88.35951 9.2400305 21 27.2937347 66.462032 68.99841 87.99545 85.37381 87.9685 87.6696 8.9068885 22 25.8838437 65.108541 67.53419 87.12958 84.64163 87.27584 86.97969 8.6936999 23 24.3993152 63.8076 66.13796 86.26581 83.90944 86.22379 86.28978 8.6342607 24 22.9890026 61.972916 64.74173 85.65 83.17726 85.10596 85.59988 8.3770262 25 21.6575443 60.806864 63.3455 85.03 82.44508 84.46754 84.90997 7.7179368 26 20.4163203 59.114091 61.94927 84.57 81.7129 83.74766 84.22006 7.8988314 27 19.4514238 57.632007 60.55304 84.022 80.98071 82.86953 83.53015 7.6103339 28 18.6894202 56.38168 59.15681 83.516 80.24853 82.06285 82.84024 7.2714806 29 18.0016998 55.608672 57.76058 83.111 79.51635 81.25617 82.15033 7.0327165 30 17.3384109 54.824281 56.36435 82.587 78.78417 80.44949 81.46042 6.8154628 (Unit: % capacity) Referring to Figures 13A to 13H, it can be seen that, over a total of 30 cycles, the all-solid-state batteries manufactured according to Examples 1 to 7 exhibit superior discharge capacity compared to the all-solid-state batteries manufactured according to the comparative examples.

[0210] Reference Figure 14 It can be seen that the capacity retention of thin film electrodes tends to increase with increasing thickness when the thickness is greater than or equal to 50 nm, and saturates when the thickness is greater than or equal to 500 nm.

[0211] While this disclosure has been described in conjunction with what is now considered to be actual embodiments, it should be understood that this disclosure is not limited to the disclosed embodiments, but rather is intended to cover various variations and equivalent arrangements included within the spirit and scope of the appended claims.

[0212] <Explanation of reference numerals in the attached figures> 1000: All-solid-state battery 100: Layered body 110: Solid electrolyte layer 130: Positive electrode layer 133: Positive current collector 135, 136: Positive electrode active material layer 150: Negative electrode layer 153: Negative current collector 155, 156: Negative electrode active material layer 160: Upper protective layer 170: Lower protective layer 180, 181, 183: Edges 210: First thin-film electrode 220: Second thin-film electrode 300: First external electrode 400: Second external electrode.

Claims

1. A solid-state battery comprising: a laminate including a first surface and a second surface opposite to each other in a first direction, a third surface and a fourth surface opposite to each other and connecting the first surface and the second surface in a second direction, and a fifth surface and a sixth surface opposite to each other and connecting the first surface and the second surface in a third direction, the laminate including a positive electrode layer, a negative electrode layer, and a solid electrolyte layer provided between the positive electrode layer and the negative electrode layer and including a solid electrolyte; a first thin film electrode directly connected to the positive electrode layer and the solid electrolyte layer on the first surface of the laminate; a second thin film electrode directly connected to the negative electrode layer and the solid electrolyte layer on the second surface of the laminate; a first external electrode connected to the first thin film electrode and covering at least a portion of the laminate; and a second external electrode connected to the second thin film electrode and covering at least a portion of the laminate. The first external electrode and the second external electrode include silver (Ag).

2. The all-solid battery according to claim 1, wherein The first external electrode and the second external electrode include a base resin and a conductive metal, the conductive metal including silver (Ag).

3. The all-solid battery according to claim 1, wherein The base resin includes an epoxy resin.

4. The all-solid battery according to claim 3, wherein The first thin film electrode and the second thin film electrode are sputtering electrodes.

5. The all-solid battery according to claim 1, wherein A thickness of the first thin film electrode is equal to or greater than 50 nm and equal to or less than 1 μm, and a thickness of the second thin film electrode is equal to or greater than 50 nm and equal to or less than 1 μm.

6. The all-solid battery according to claim 1, wherein A thickness of the first thin film electrode is equal to or greater than 50 nm and equal to or less than 500 nm, and a thickness of the second thin film electrode is equal to or greater than 50 nm and equal to or less than 500 nm.

7. The all-solid battery according to claim 1, wherein At least one of the thickness of the first thin film electrode and the thickness of the second thin film electrode is equal to or greater than 50 nm and equal to or less than 500 nm.

8. The all-solid battery according to claim 1, wherein The first thin film electrode covers a portion of the first surface of the laminate, and the second thin film electrode covers a portion of the second surface of the laminate.

9. The all-solid battery according to claim 1, wherein The first external electrode covers the first thin film electrode and covers a portion of the first surface of the laminate on which the first thin film electrode is not provided, and the second external electrode covers the second thin film electrode and covers a portion of the second surface of the laminate on which the second thin film electrode is not provided.

10. The all-solid battery according to claim 8, wherein The first external electrode covers a portion of the fifth surface of the laminate and a portion of the sixth surface of the laminate, and the second external electrode covers another portion of the fifth surface of the laminate and another portion of the sixth surface of the laminate.

11. The all-solid battery according to claim 10, wherein The first thin film electrode completely covers the first surface of the laminate, and the second thin film electrode completely covers the second surface of the laminate.

12. The all-solid-state battery according to claim 1, wherein The first external electrode covers the first thin film electrode and covers a portion of the fifth surface of the laminate and a portion of the sixth surface of the laminate, and the second external electrode covers the second thin film electrode and covers another portion of the fifth surface of the laminate and another portion of the sixth surface of the laminate.

13. The all-solid-state battery according to claim 12, wherein ​ 14. The all-solid-state battery according to claim 1, wherein The first thin film electrode completely covers the first surface of the laminate and covers a part of the fifth surface and a part of the sixth surface of the laminate, and the second thin film electrode completely covers the second surface of the laminate and covers another part of the fifth surface and another part of the sixth surface of the laminate.

15. The all-solid-state battery according to claim 14, wherein The first outer electrode completely covers the first thin film electrode, and the second outer electrode completely covers the second thin film electrode.

16. The all-solid-state battery according to claim 1, wherein, The first thin film electrode and the second thin film electrode each include platinum (Pt), gold (Au), nickel (Ni), chromium (Cr), molybdenum (Mo), or a combination thereof.

17. The all-solid-state battery of claim 1, wherein The positive electrode layer includes a positive electrode current collector and a positive electrode active material layer, and the negative electrode layer includes a negative electrode active material layer.

18. A all-solid-state battery comprising: a laminate including a first surface and a second surface opposite to each other in a first direction, a third surface and a fourth surface opposite to each other and connecting the first surface and the second surface in a second direction, and a fifth surface and a sixth surface opposite to each other and connecting the first surface and the second surface in a third direction, the laminate including a positive electrode layer, a negative electrode layer, and a solid electrolyte layer provided between the positive electrode layer and the negative electrode layer and including a solid electrolyte; a first outer electrode provided at least on the first surface; a second outer electrode provided at least on the second surface; a first metal electrode provided on the first surface to connect the positive electrode layer to the first outer electrode; and a second metal electrode provided on the second surface to connect the negative electrode layer to the second outer electrode. The first outer electrode and the second outer electrode include a base resin and a conductive metal, the conductive metal including silver (Ag).

19. The all-solid-state battery of claim 18, wherein, A metal included in the first metal electrode continuously extends from the positive electrode layer to the first outer electrode, and 20. The all-solid-state battery of claim 18, wherein, A metal included in the second metal electrode continuously extends from the negative electrode layer to the second outer electrode. One of a thickness of the first metal electrode and a thickness of the second metal electrode is equal to or greater than 50 nm and equal to or less than 1 µm.

21. The all-solid-state battery of claim 18, wherein, One of a thickness of the first metal electrode and a thickness of the second metal electrode is equal to or greater than 50 nm and equal to or less than 500 nm.

22. The all-solid-state battery of claim 18, wherein, One of a thickness of the first metal electrode and a thickness of the second metal electrode is equal to or greater than 200 nm and equal to or less than 1 µm.

23. The all-solid-state battery according to claim 18, wherein, 24. A all-solid-state battery comprising: a laminate including a first surface and a second surface opposite to each other in a first direction, a third surface and a fourth surface opposite to each other and connecting the first surface and the second surface in a second direction, and a fifth surface and a sixth surface opposite to each other and connecting the first surface and the second surface in a third direction, the laminate including a positive electrode layer, a negative electrode layer, and a solid electrolyte layer provided between the positive electrode layer and the negative electrode layer and including a solid electrolyte; a first outer electrode provided at least on the first surface; a second outer electrode provided at least on the second surface; ​ a first electrode provided on the first surface to connect the positive electrode layer to the first external electrode and having a thickness of 1 μm or less; and a second electrode provided on the second surface to connect the negative electrode layer to the second external electrode and having a thickness of 1 μm or less.

25. The all-solid-state battery of claim 24, wherein, The first external electrode and the second external electrode include a base resin and a conductive metal, the conductive metal including silver (Ag).

26. The all-solid-state battery of claim 24, wherein, One of the thickness of the first electrode and the thickness of the second electrode is 50 nm or more and 1 μm or less.

27. The all-solid-state battery of claim 24, wherein, One of the thickness of the first electrode and the thickness of the second electrode is 50 nm or more and 500 nm or less.

28. The all-solid-state battery of claim 24, wherein, One of the thickness of the first electrode and the thickness of the second electrode is 200 nm or more and 1 μm or less.

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