All-solid-state battery

Abstract

An all-solid-state battery includes a laminate comprising a positive electrode layer, a solid electrolyte layer, and a negative electrode layer stacked in a first direction. A first external electrode is connected to the positive electrode layer and disposed on the laminate, and a second external electrode is connected to the negative electrode layer and disposed on the laminate. The positive electrode layer includes a positive electrode current collector and a positive electrode active material layer in contact with the solid electrolyte layer, and the negative electrode layer includes a negative electrode current collector and a negative electrode active material layer in contact with the solid electrolyte layer. The laminate is curved in a second direction intersecting the first direction.

Description

ALL-SOLID-STATE BATTERY

[0001] The present disclosure relates to an all-solid-state battery.

[0002] Currently, commercially available lithium-ion batteries use an electrolyte containing a flammable organic solvent, posing a risk of overheating and fire in the event of a short circuit. Accordingly, an all-solid-state battery using a solid electrolyte instead of an electrolyte solution has been proposed.

[0003] Recently, wearable electronic devices have become widespread, and all-solid-state batteries that can be installed in wearable electronic devices of various shapes are in demand.

[0004] The present disclosure aims to provide an all-solid-state battery that can be installed in a ring-shaped wearable electronic device.

[0005] However, the objective of the present disclosure is not limited to the aforementioned one, and may be extended in various ways within the spirit and scope of the present disclosure.

[0006] An all-solid-state battery may include a laminate including a positive electrode layer, a solid electrolyte layer, and a negative electrode layer that are stacked in a first direction, a first external electrode disposed outside the laminate and connected to the positive electrode layer, and a second external electrode disposed outside the laminate and connected to the negative electrode layer, where the positive electrode layer may include a positive electrode current collector and a positive electrode active material layer disposed on the positive electrode current collector and in contact with the solid electrolyte layer, where the negative electrode layer may include a negative electrode current collector and a negative electrode active material layer disposed on the negative electrode current collector and in contact with the solid electrolyte layer, and where the laminate is curved in a second direction intersecting the first direction.

[0007] The laminate may have a curvature.

[0008] The laminate may include a first surface and a second surface disposed opposite each other in the second direction, the first surface may have a first radius of curvature, and the second surface may have a second radius of curvature.

[0009] The first radius of curvature may be smaller than the second radius of curvature.

[0010] When viewed in the first direction, the first surface and the second surface may exhibit a circular arc shape or an elliptical arc shape.

[0011] When viewed in the first direction, the first surface and the second surface may form parts of concentric circles.

[0012] The positive electrode layer, the solid electrolyte layer, and the negative electrode layer may have curvatures that correspond to the laminate, respectively.

[0013] The laminate may include a first end surface and a second end surface disposed opposite each other in a third direction intersecting simultaneously with the first direction and the second direction and extending between the first surface and the second surface, the first external electrode may be disposed on the first end surface, and the second external electrode may be disposed on the second end surface.

[0014] The laminate may include a third surface and a fourth surface disposed opposite each other in the first direction, the first external electrode may extend from the first end surface to cover a portion of the third surface and a portion of the fourth surface, and the second external electrode may extend from the second end surface to cover a portion of the third surface and a portion of the fourth surface.

[0015] The laminate may include a first end surface and a second end surface disposed opposite each other in a third direction intersecting simultaneously with the first direction and the second direction and extending between the first surface and the second surface, and a third surface and a fourth surface disposed opposite each other in the first direction, the first external electrode may include a first connection portion disposed on the first end surface and a first lead-out portion connected to the first connection portion and disposed on the fourth surface, and the second external electrode may include a second connection portion disposed on the second end surface and a second lead-out portion connected to the second connection portion and disposed on the fourth surface.

[0016] An all-solid-state battery may further include a first insulation layer covering the first connection portion on the first end surface and a second insulation layer covering the second connection portion on the second end surface. An all-solid-state battery according to an embodiment may be mounted in a ring-shaped wearable electronic device.

[0017] FIG. 1 is a perspective view schematically illustrating an all-solid-state battery according to an embodiment.

[0018] FIG. 2 is a top plan view illustrating the all-solid-state battery of FIG. 1.

[0019] FIG. 3 is a perspective view schematically illustrating the laminate of FIG. 1.

[0020] FIG. 4 is a front view schematically illustrating the laminate of FIG. 1.

[0021] FIG. 5 is a cross-sectional view taken along line I-I' of FIG. 2.

[0022] FIG. 6 is a cross-sectional view taken along line II-II' of FIG. 2.

[0023] FIG. 7 is a partial cross-sectional view schematically illustrating a positive electrode layer of the all-solid-state battery of FIG. 1.

[0024] FIG. 8 is a partial cross-sectional view schematically illustrating a negative electrode layer of the all-solid-state battery of FIG. 1.

[0025] FIG. 9 is a top plan view schematically illustrating a positive electrode layer of the all-solid-state battery of FIG. 1.

[0026] FIG. 10 is a top plan view schematically illustrating a negative electrode layer of the all-solid-state battery of FIG. 1.

[0027] FIG. 11 is a perspective view schematically illustrating an all-solid-state battery according to another embodiment.

[0028] FIG. 12 is a top plan view illustrating the all-solid-state battery of FIG. 11.

[0029] FIG. 13 is a bottom view illustrating the all-solid-state battery of FIG. 11.

[0030] FIG. 14 is a cross-sectional view taken along line III-III' of FIG. 12.

[0031] FIG. 15 is a cross-sectional view taken along line IV-IV' of FIG. 12.

[0032] FIG. 16 is a perspective view schematically illustrating a ring-shaped wearable electronic device on which an all-solid-state battery according to an embodiment is mounted.

[0033] The present disclosure will be described in greater detail hereinafter with reference to the accompanying drawings, in which embodiments of the disclosure are shown. The drawings and description are to be regarded as illustrative in nature and not restrictive. Like reference numerals designate corresponding elements throughout the specification. In addition, some components are exaggerated, omitted, or briefly illustrated in the accompanying drawings, and sizes of the respective components do not reflect the actual sizes.

[0034] The accompanying drawings are provided only in order to allow embodiments disclosed in the present specification to be easily understood and are not to be interpreted as limiting the spirit disclosed in the present specification, and it is to be understood that the present disclosure includes all modifications, equivalents, and substitutions without departing from the scope and spirit of the present disclosure.

[0035] Terms including ordinal numbers such as first, second, and the like will be used only to describe various components, and are not to be interpreted as limiting these components. The terms are only used to differentiate one component from other components.

[0036] It will be understood that when an element such as a layer, film, region, area, or substrate is referred to as being "on" or "above" another element, it can be directly on the other element or intervening elements may also be present. In contrast, when an element is referred to as being "directly on" another element, there are no intervening elements present. Further, in the specification, the word "on" or "above" means disposed on or below the object portion, and does not necessarily mean disposed on the upper side of the object portion based on a gravitational direction.

[0037] Throughout the specification, it should be understood that the term "include", "comprise", "have", or "configure" indicates that a feature, a number, a step, an operation, a component, a part, or a combination thereof described in the specification is present, but does not exclude a possibility of presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations, in advance. Unless explicitly described to the contrary, the word "comprise" and variations such as "comprises" or "comprising" will be understood to imply the inclusion of stated elements but not the exclusion of any other elements.

[0038] Furthermore, throughout the specification, the phrase "in a plan view" or "on a plane" means viewing a target portion from the top, and the phrase "in a cross-sectional view" or "on a cross-section" means viewing a cross-section formed by vertically cutting a target portion from the side.

[0039] Furthermore, throughout the specification, "connected" refers not only to situations where two or more elements are directly connected, but also when two or more elements are indirectly connected through other elements, and when they are physically connected or electrically connected, and further, it may be referred to by different names depending on a position or function, and may also be referred to as a case in which respective parts that are substantially integrated are linked to each other.

[0040] FIG. 1 is a perspective view schematically illustrating an all-solid-state battery according to an embodiment, and FIG. 2 is a top plan view showing the all-solid-state battery of FIG. 1, and FIG. 3 is a perspective view schematically showing a laminate of FIG. 1, and FIG. 4 is a front view schematically showing the laminate of FIG. 1.

[0041] Referring to FIG. 1 and FIG. 2, an all-solid-state battery 1000 according to the present embodiment may include a laminate 100, a first external electrode 200, and a second external electrode 300.

[0042] Referring to FIG. 2, FIG. 3, and FIG. 4, the laminate 100 may have a partial doughnut shape or a partial ring shape, and may include a solid electrolyte layer 110, a positive electrode layer 130, and a negative electrode layer 150.

[0043] The laminate 100 is a structure comprising the solid electrolyte layer 110, the positive electrode layer 130, and the negative electrode layer 150 stacked in a thickness direction (z-axis direction), and may have a shape curved around the thickness direction (z-axis direction). That is, the laminate 100 has curvature by being curved in a direction that intersects with the thickness direction (z-axis direction).

[0044] Here, the thickness direction (z-axis direction) may be a direction perpendicular to a wide surface (major surface) of sheet-like components. For example, the thickness direction (z-axis direction) may be used as the same concept as a direction in which components of the laminate 100 are stacked.

[0045] The laminate 100 may include a first surface S1, a second surface S2, a third surface S3, a fourth surface S4, a fifth surface S5 and a sixth surface S6.

[0046] The first surface S1 and the second surface S2 oppose each other in the thickness direction (z-axis direction). That is, the first surface S1 and the second surface S2 may be disposed opposite each other in the thickness direction (z-axis direction).

[0047] The third surface S3 may be a curved surface connecting the first surface S1 and the second surface S2, and the fourth surface S4 may be another curved surface connecting the first surface S1 and the second surface S2. Here, for convenience of description, a direction of an arbitrary straight line that is substantially perpendicular to the thickness direction (z-axis direction) and passes simultaneously through the third surface S3 and the fourth surface S4 will be defined as the ‘radial direction‘. Accordingly, the third surface S3 and the fourth surface S4 may be positioned opposite each other in the radial direction.

[0048] When viewed in the thickness direction (z-axis direction), the third surface S3 and the fourth surface S4 of the laminate 100 may have curvatures, respectively. That is, the third surface S3 may have a first radius of curvature, and the fourth surface S4 may have a second radius of curvature. The second radius of curvature may be smaller than the first radius of curvature.

[0049] For example, the third surface S3 and the fourth surface S4 may exhibit a circular arc shape or an elliptical arc shape. As another example, the third surface S3 and the fourth surface S4 may form parts of concentric circles.

[0050] Here, for convenience of description, a direction along an imaginary curved surface (or curve) extending between the third surface S3 and the fourth surface S4 of the laminate 100 that intersects simultaneously with the thickness direction (z-axis direction) and the radial direction will be defined as the ’circumferential direction‘.

[0051] The fifth surface S5 and the sixth surface S6 may be two end surfaces in the circumferential direction of the laminate 100. That is, the fifth surface S5 and the sixth surface S6 may be positioned opposite each other in the circumferential direction.

[0052] FIG. 5 is a cross-sectional view taken along line I-I' of FIG. 2, and FIG. 6 is a cross-sectional view taken along line II-II' of FIG. 2.

[0053] Referring to FIG. 4, FIG. 5, and FIG. 6, the laminate 100 may include the solid electrolyte layer 110, the positive electrode layer 130, the negative electrode layer 150, an upper protective layer 160, a lower protective layer 170 and a margin portion 180.

[0054] The solid electrolyte layer 110, the positive electrode layer 130 and the negative electrode layer 150 may each be plural. The positive electrode layer 130 and the negative electrode layer 150 may be alternately stacked in the thickness direction (z-axis direction) with the solid electrolyte layer 110 interposed between them. Such a laminated structure may repeat within the laminate 100, the electrode layer closest to the first surface S1 of the laminate 100 may be the positive electrode layer 130 or the negative electrode layer 150, and the electrode layer closest to the second surface S2 may be the negative electrode layer 150 or the positive electrode layer 130.

[0055] 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.

[0056] The solid electrolyte layer 110 may include a solid electrolyte. The solid electrolyte may serve as a passage for lithium (Li) ions.

[0057] The solid electrolyte included in the solid electrolyte layer 110 may include a glass-ceramic electrolyte including lithium halide (LiX, where X is a halogen element such as F, Br, Cl, I, or the like). The glass-ceramic (or crystallization glass) refers to that a crystallographic mixture of amorphous and crystalline materials from which peaks and halos are observed in X-ray diffraction, electron beam diffraction, etc. Therefore, the glass-ceramic-based electrolyte is an electrolyte that has undergone partial crystallization through sintering, resulting in a mixture of amorphous and crystalline materials.

[0058] The glass-ceramic-based electrolyte may include a mixture of an amorphous material and two or more types of crystalline materials. Additionally, the crystalline material included in the glass-ceramic-based electrolyte may include a lithium compound crystalline phase containing lithium.

[0059] When the glass-ceramic-based electrolyte is included in the solid electrolyte layer 110, sufficient densification is achieved after sintering, whereby it is possible to realize high ionic conductivity.

[0060] For example, the glass-ceramic electrolyte may include 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, the glass-ceramic electrolyte may include Li2O-B2O3-SiO2-P2O5-GeO2-LiCl.

[0061] As another example, the solid electrolyte included in the solid electrolyte layer 110 may contain a lithium-borosilicate-based electrolyte (hereinafter, referred to as LBSO-based electrolyte). The LBSO-based electrolyte is a glass-state electrolyte, and glass refers to a crystallographically amorphous material, from which halos are observed in the X-ray diffraction or electron beam diffraction.

[0062] When the LBSO-based electrolyte is included in the solid electrolyte layer 110, it is possible to keep the amorphous state during sintering while lowering the sintering temperature.　 Therefore, there is an advantage that it is possible to realize high ionic conductivity, and reactivity with the electrode is not high. The LBSO-based electrolyte may include lithium (Li), boron (B), silicon (Si), aluminum (Al), phosphorus (P), germanium (Ge), and sulfur (S).

[0063] Alternatively, the solid electrolyte included in the solid electrolyte layer 110 may be one or more types selected from the group consisting of a Garnet-type, a Na super ionic conductor (NASICON)-type, a lithium super ionic conductor (LISICON)-type, a Perovskite-type, and a lithium phosphorus oxynitride (LiPON)-type.

[0064] In an area where the margin portion 180, which will be described later, is disposed, a material having a low ionic conductivity and electrical conductivity, i.e. an insulating material, may be present, or a material having an ionic conductivity (or electrical conductivity) similar to the ionic conductivity (or electrical conductivity) of the solid electrolyte may be present. For example, when a material having ionic conductivity (or electrical conductivity) similar to the ionic conductivity (or electrical conductivity) of the solid electrolyte is present in the margin portion, the material may be a material that is identical to or different from the solid electrolyte in other regions. In another example, a material with ionic conductivity (or electrical conductivity) similar to that of the solid electrolyte and an insulating material may coexist in the margin portion.

[0065] The Garnet-type solid electrolyte may refer to lithium lanthanum zirconium oxide (LLZO) represented by LiaLabZrcO12such as Li7La3Zr2O12, and the NASICON-type solid electrolyte may include lithium-aluminum-titanium-phosphate (LATP) of Li1+xAlxTi2-x(PO4)3(wherein 0<x<1) produced by introducing Ti to Li1+xAlxM2-x(PO4)3(LAMP) (wherein 0<x<2, M is Zr, Ti, or Ge)-type compound, lithium-aluminum-germanium-phosphate (LAGP) represented by Li1+xAlxGe2-x(PO4)3(wherein 0<x<1), such as Li1.3Al0.3Ge1.7(PO4)3containing an excessive amount of lithium, and / or lithium-zirconium-phosphate (LZP) of LiZr2(PO4)3.

[0066] Additionally, the LISICON-type solid electrolyte may include solid solution oxide represented by xLi3AO4-(1-x)Li4BO4(wherein A is P, As, V, etc., and B is Si, Ge, Ti, etc.), such as Li4Zn(GeO4)4, Li10GeP2O12(LGPO), Li3.5Si0.5P0.5O4, and Li10.42Si(Ge)1.5P1.5Cl0.08O11.92, etc., and solid solution sulfide represented by Li4-xM1-yM'yS4(wherein M is Si or Ge and M' is P, Al, Zn, or Ga), such as Li2S-P2S5, Li2S-SiS2, Li2S-SiS2-P2S5, or Li2S-GeS2.

[0067] Furthermore, the Perovskite-type solid electrolyte may include lithium lanthanum titanate (LLTO) represented by Li3xLa2 / 3-x□1 / 3-2xTiO3(wherein 0<x<0.16, and □ is vacancy), such as Li1 / 8La5 / 8TiO3, and the LiPON-type solid electrolyte may include nitride such as lithium phosphorous oxynitride of Li2.8PO3.3N0.46.

[0068] The positive electrode layer 130 may be exposed outside the laminate 100 from the fifth surface S5, and connected to the first external electrode 200.

[0069] FIG. 7 is a partial cross-sectional view schematically showing the positive electrode layer of the all-solid-state battery of FIG. 1.

[0070] Referring to FIG. 7, 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.

[0071] For example, the positive electrode current collector 133 may be made of a plate-shape member or a thin member. As another example, the positive electrode current collector 133 may be a porous body having a reticulate shape, a mesh shape, or the like.

[0072] The positive electrode current collector 133 may include a first surface 133a and a second surface 133b, which oppose each other in the thickness direction (z-axis direction). The positive electrode current collector 133 may include, but not limited to, a porous metal plate made of stainless steel, nickel (Ni), copper (Cu), tin (Sn), aluminum (Al), or an alloy thereof.

[0073] Additionally, the positive electrode current collector 133 may be coated with an oxidation-resistant metal or an oxidation-resistant alloy film to prevent oxidation.

[0074] The positive electrode current collector 133 may include a carbon-based plate-shaped, thin, or linear member. The positive electrode current collector 133 may include a conductive carbon material. The conductive carbon material may include graphite, conductive fiber such as carbon nanotube (CNT) or vapor grown carbon fiber (VGCF), or conductive carbon such as carbon black.

[0075] Additionally, the positive electrode current collector may also include one or more types of solid electrolyte.

[0076] The first positive electrode active material layer 135 and the second positive electrode active material layer 136 may include a positive electrode active material, and may be disposed on a 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 a positive electrode active material on one or both surfaces of the positive electrode current collector 133, but the method for forming the positive electrode active material layer is not limited thereto.

[0077] The positive electrode active material included in the positive electrode active material layers 135 and 136 may comprise a material containing lithium (Li) ions. The positive electrode active material may reversibly intercalate and deintercalate lithium ions. In other words, the positive electrode active material may contain lithium ions and serve to provide the lithium ions to the negative electrode when the all-solid-state battery is being charged. The positive electrode active material may affect the capacity and output of the all-solid-state battery.

[0078] For example, the positive electrode active material may include at least one selected from the group consisting of compounds represented by the following formula: LiaAl-bMbD2(where, 0.90≤a≤1.8, 0≤b≤0.5); LiaEl-bMbO2-cDc(where, 0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.05); LiE2-bMbO4-cDc(where, 0≤b≤0.5, 0≤c≤0.05); LiaNi1-b-cCobMcDα(where, 0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.05, 0<α≤2); LiaNi1-b-cCobMcO2-αXα(where, 0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.05, 0<α<2); LiaNi1-b-cCobMcO2-αX2(where, 0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.05,0<α<2); LiaNi1-b-cMnbMcDα(where, 0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.05, 0<α≤2); LiaNi1-b-cMnbMcO2-αXα(where,0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.05, 0<α<2); LiaNi1-b-cMnbMcO2-αX2(where, 0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.05, 0<α<2); LiaNibEcGdO2(where, 0.90≤a≤1.8, 0≤b≤0.9, 0≤c≤0.5, 0.001≤d≤0.1); LiaNibCocMndGeO2(where,0.90≤a≤1.8, 0≤b≤0.9, 0≤c≤0.5, 0≤d≤0.5, 0.001≤e≤0.1); LiaNiGbO2(where, 0.90≤a≤1.8, 0.001≤b≤0.1); LiaCoGbO2(where, 0.90≤a≤1.8, 0.001≤b≤0.1); LiaMnGbO2 (where, 0.90≤a≤1.8, 0.001≤b≤0.1); LiaMn2GbO4(where, 0.90≤a≤1.8, 0.001≤b≤0.1); QO2; QS2; LiQS2; V2O5; LiV2O2; LiRO2; LiNiVO4; Li(3-f)J2(PO4)3(0≤f≤2); Li(3-f)Fe2(PO4)3(where, 0≤f≤2); and LiFePO4, where in the above formula, A is Ni, Co, or Mn; M is Al, Ni, Co, Mn, Cr, Fe, Mg, Sr, V, Nb, Ti or rare-earth element; D is O, F, S, or P; E is Co or Mn; X is F, S, or P; G is Al, Cr, Mn, Fe, Mg, La, Ce, Sr, or V; Q is Ti, Mo or Mn; R is Cr, V, Fe, Sc, or Y; J is V, Cr, Mn, Co, Ni, or Cu.

[0079] Additionally, the positive electrode active material may also include LiCoO2, LiMnxO2x(where, x is 1 or 2), LiNi1-xMnxO2x(where, 0<x<1), LiNi1-x-yCoxMnyO2(where, 0≤x≤0.5, 0≤y≤0.5), LiFePO4, TiS2, FeS2, TiS3, or FeS3, but is not limited thereto.

[0080] The positive electrode active material may optionally include a conductive material and a binder. However, because an organic substance such as a binder decomposes during sintering process, the organic material may not remain on the positive electrode active material layer of the obtained positive electrode current collector.

[0081] The conductive material is not particularly limited as long as it has conductivity without causing chemical changes in the all-solid-state battery 1000. For example, graphite such as natural graphite and artificial graphite; carbon-based materials such as carbon black, acetylene black, Ketjenblack®, channel black, furnace black, lamp black, and thermal black; conductive fibers such as carbon fibers, metal fibers, etc.; carbon fluoride; metal components such as lithium (Li), tin (Sn), aluminum (Al), nickel (Ni), copper (Cu), etc., oxides thereof, nitrides thereof, or fluorides thereof; conductive whiskers such as zinc oxide and potassium titanate; conductive metal oxides such as titanium oxide; conductive materials such as polyphenylene derivatives, etc., may be used.

[0082] The binder may be used to improve the bonding strength of the active material, the conductive material, or the like. The binder may include, but 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 terpolymer (EPDM), sulfonated EPDM, styrene butadiene rubber (SBR), fluorine rubber, various copolymers, etc.

[0083] Additionally, the positive electrode layer 130 may further contain a solid electrolyte component. The solid electrolyte component may contain one or more of the above-described components, and may serve as an ionic conduction channel in the positive electrode layer. Therefore, it is possible to reduce interface resistance.

[0084] FIG. 9 is a top plan view schematically illustrating the positive electrode layer of the all-solid-state battery of FIG. 1.

[0085] Referring to FIG. 9, the positive electrode layer 130 has a shape that corresponds to a shape of the laminate 100. That is, the positive electrode layer 130 has a partial doughnut shape or a partial ring shape.

[0086] The edges of the positive electrode layer 130, except for the portion where the positive electrode layer 130 is connected to the first external electrode 200, may be spaced apart from the edges of the laminate 100, and the margin portion 180 may be disposed in the space therebetween.

[0087] The negative electrode layer 150 may be exposed outside of the laminate 100 from the sixth surface S6, and connected to the second external electrode 300.

[0088] FIG. 8 is a partial cross-sectional view schematically illustrating the negative electrode layer of the all-solid-state battery of FIG. 1.

[0089] Referring to FIG. 8, 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.

[0090] The negative electrode current collector 153 may be formed from, for example, a plate-shaped member or a thin member. As another example, the negative electrode current collector 153 may include a porous body having a reticulate shape, a mesh shape, or the like.

[0091] 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 oppose each other in the thickness direction (z-axis direction).

[0092] For example, the negative electrode current collector 153 may include, but not limited to, a porous metal plate made of stainless steel, nickel (Ni), copper (Cu), tin (Sn), aluminum (Al), or an alloy thereof.

[0093] Additionally, the negative electrode current collector 153 may be coated with an oxidation-resistant metal or an oxidation-resistant alloy film to prevent oxidation.

[0094] The negative electrode current collector 153, like 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 identical to the negative electrode active material layers 155 and 156.

[0095] The first negative electrode active material layer 155 and the second negative electrode active material layer 156 may include negative electrode active materials and be disposed on a surface of the negative electrode current collector 153. The first negative electrode active material layer 155 and the second negative electrode active material layer 156 may be formed by printing a negative electrode active material on one or both surfaces of the negative electrode current collector 153. However, the method for forming the negative electrode active material layer is not limited to printing.

[0096] The negative electrode active material included in the negative electrode active material layers 155 and 156 may store the lithium ions that have moved from the positive electrode and release the lithium ions when the all-solid-state battery is discharged, thereby generating electrical energy. A carbon-based material, silicon, a silicon oxide, a silicon-based alloy, a silicon-carbon-based material composite, tin, a tin-based alloy, a tin-carbon composite, a metal oxide, or a combination thereof may be used as the negative electrode active material. The negative electrode active material may contain a lithium metal and / or a lithium metal alloy.

[0097] The lithium metal alloy may contain lithium, and a metal / metalloid capable of making an alloy with lithium. For example, the metal / metalloid capable of making an alloy with lithium may include Si, Sn, Al, Ge, Pb, Bi, Sb, and Si-AM alloy (wherein AM is an alkali metal, an alkaline earth metal, an element in group 13 to 16, a transition metal, a rare-earth element, or a combination thereof, and does not include Si), Sn-AM alloys (wherein AM is an alkali metal, an alkaline earth metal, an element in group 13 to 16, a transition metal, a transition metal oxide such as lithium titanium oxide (Li4Ti5O12), a rare-earth element, or combinations thereof, and does not include Sn), MnOx(wherein 0<x≤2), and the like.

[0098] 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 combinations thereof.

[0099] Additionally, the oxide of the metal / metalloid capable of making an alloy with lithium may include lithium titanium oxide, vanadium oxide, lithium vanadium oxide, SnO2, SiOx(wherein 0<x<2), or the like. For example, the negative electrode active material may include one or more elements selected from the group consisting of the elements in group 13 to 16 of the periodic table of elements. For example, the negative electrode active material may contain one or more elements selected from the group consisting of Si, Ge, and Sn.

[0100] 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 that is in a shapeless, disc-shaped, flake-shaped, globular, or fibrous form. In addition, the amorphous carbon may include, but not limited to, soft carbon (low-temperature calcined carbon), hard carbon, mesophase pitch carbide, calcined coke, graphene, carbon black, fullerene soot, carbon nanotube, carbon fiber, etc.

[0101] The silicon may include at least one selected from the group consisting of Si, SiOx(wherein 0<x<2, for example, 0.5 to 1.5), Sn, SnO2, or silicon-containing metal alloy, and mixtures thereof. For example, the silicon-containing metal alloy may include silicon, and one or more of Al, Sn, Ag, Fe, Bi, Mg, Zn, in, Ge, Pb, or Ti.

[0102] The negative active material may optionally include a conductive material and a binder.

[0103] The conductive material is not particularly limited as long as it has conductivity without causing chemical changes in the all-solid-state battery 1000. For example, graphite such as natural graphite and artificial graphite; carbon-based materials such as carbon black, acetylene black, Ketjenblack®, channel black, furnace black, lamp black, and thermal black; conductive fibers such as carbon fibers, metal fibers, etc.; carbon fluoride; metal components such as lithium (Li), tin (Sn), aluminum (Al), nickel (Ni), copper (Cu), etc., oxides thereof, nitrides thereof, or fluorides thereof; conductive whiskers such as zinc oxide and potassium titanate; conductive metal oxides such as titanium oxide; conductive materials such as polyphenylene derivatives, etc., may be used.

[0104] The binder may be used to improve the bonding strength of the active material, the conductive material, or the like. The binder may include, but 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 terpolymer (EPDM), sulfonated EPDM, styrene butadiene rubber (SBR), fluorine rubber, various copolymers, etc.

[0105] Additionally, the negative electrode layer 150 may further contain a solid electrolyte component. The solid electrolyte component may contain one or more of the above-described components and may serve as an ionic conduction channel in the negative electrode layer. Therefore, it is possible to reduce interface resistance.

[0106] FIG. 10 is a top plan view schematically showing the negative electrode layer of the all-solid-state battery of FIG. 1.

[0107] Referring to FIG. 10, the negative electrode layer 150 may have a shape that corresponds to the shape of the laminate 100. That is, the negative electrode layer 150 may have a partial doughnut shape or a partial ring shape.

[0108] The edges of the negative electrode layer 150, except for the portion where the negative electrode layer 150 is connected to the second external electrode 300, may be spaced apart from the edges of the laminate 100, and the margin portion 180 may be disposed in the space therebetween.

[0109] Referring to FIG. 4, FIG. 5 and FIG. 6, the upper protective layer 160 and the lower protective layer 170 may be the outermost layers toward the first surface S1 and the second surface S2 of the laminate 100, respectively. That is, the upper protective layer 160 may be the outermost layer toward the first surface S1 of the laminate 100, and the lower protective layer 170 may be the outermost layer toward the second surface S2 of the laminate 100. The upper protective layer 160 and the lower protective layer 170 may improve moisture resistance by preventing moisture penetration, and prevent damage from physical and chemical impacts.

[0110] The upper protective layer 160 and the lower protective layer 170 may be insulation layers made of an insulating material, that is, a material that does not have electrical conductivity (ionic conductivity).

[0111] The upper protective layer 160 and the lower protective layer 170 may include a ceramic material, for example, alumina (Al2O3), aluminum nitride (AlN), beryllium oxide (BeO), boron nitride (BN), silicon (Si), silicon carbide (SiC), silica (SiO2), silicon nitride (Si3N4), gallium arsenide (GaAs), gallium nitride (GaN), barium titanate (BaTiO3), zirconium dioxide (ZrO2), mixtures thereof, oxides and / or nitrides of such materials, or any other suitable ceramic materials, but is not limited thereto. In addition, the upper protective layer 160 and the lower protective layer 170 may selectively include the above-described solid electrolytes, and may include one or more types of solid electrolytes, but are not limited thereto.

[0112] The margin portion 180 may be positioned along the edges of the positive electrode layer 130 and the negative electrode layer 150. The margin portion 180 may be disposed to be in contact with a remaining edge of the positive electrode layer 130, except where the positive electrode layer 130 is connected to the first external electrode 200. Additionally, the margin portion 180 may be positioned to contact the remaining edge of the negative electrode layer 150, except where the negative electrode layer 150 connects to the second external electrode 300.

[0113] For example, the margin portion 180 may be positioned on the solid electrolyte layer 110 in a region other than the region where the positive electrode layer 130 or the negative electrode layer 150 is disposed. When the positive electrode layer 130 is positioned on the solid electrolyte layer 110, the margin portion 180 may be disposed in a region other than the region where the positive electrode layer 130 is disposed. Likewise, when the negative electrode layer 150 is positioned on the solid electrolyte layer 110, the margin portion 180 may be positioned in a region other than the region where the negative electrode layer 150 is disposed.

[0114] Referring to FIG. 5 and FIG. 6, the margin portion 180 may comprise a portion of the fifth surface S5 and a portion of the sixth surface S6 of the laminate 100. In addition, referring to FIG. 9 and FIG. 10, the margin portion 180 may comprise a portion of the third surface S3 and a portion of the fourth surface S4 of the laminate 100.

[0115] The margin portion 180 may be disposed to compensate for a level difference between the solid electrolyte layer 110 and the positive electrode layer 130 and a level difference between the solid electrolyte layer 110 and the negative electrode layer 150. For example, the margin portion 180 may be disposed on the same surface as the positive electrode layer 130 and the negative electrode layer 150. The margin portion 180 may compensate for a level difference between the solid electrolyte layer 110 and the positive electrode layer 130 or a level 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, which may prevent interlayer delamination or warping caused by sintering during a process of manufacturing the all-solid-state battery.

[0116] Additionally, the margin portion 180 may be made of a material that is resistant to moisture and has low lithium (Li) ion conductivity. In this case, the margin portion 180 may protect the active material layers 135, 136, 155, and 156 from moisture infiltration or lithium (Li) ion leakage. For example, the margin portion 180 may include an insulating material or electrolyte material, and may include a material with an ionic conductivity of 1.0x10-10S / cm or less.

[0117] The margin portion 180 may include an insulating material, i.e., a material that is not electrically (ionically) conductive.

[0118] The margin portion 180 may include a ceramic material, for example, alumina (Al2O3), aluminum nitride (AlN), beryllium oxide (BeO), boron nitride (BN), silicon (Si), silicon carbide (SiC), silica (SiO2), silicon nitride (Si3N4), gallium arsenide (GaAs), nitride gallium (GaN), barium titanate (BaTiO3), zirconium dioxide (ZrO2), mixtures thereof, oxides and / or nitrides of these materials, or any other suitable ceramic materials, but is not limited thereto.

[0119] Additionally, the margin portion 180 may optionally include a solid electrolyte that is the same as or different from the solid electrolyte included in the above-described solid electrolyte layer, and may include one or more types of solid electrolytes, but is not limited thereto.

[0120] Additionally, a material having a low ionic conductivity and electrical conductivity, i.e., an insulating material, may be present in the margin portion 180, or a material having an ionic conductivity (or electrical conductivity) similar to the ionic conductivity (or electrical conductivity) of a solid electrolyte may be present in the margin portion 180. For example, when a material having ionic conductivity (or electrical conductivity) similar to the ionic conductivity (or electrical conductivity) of the solid electrolyte is present in the margin portion, the material may be a material that is identical to or different from the solid electrolyte in other regions. In another example, a material having ionic conductivity (or electrical conductivity) similar to the ionic conductivity (or electrical conductivity) of the solid electrolyte and an insulating material may coexist in the margin portion.

[0121] Referring to FIG. 1 and FIG. 2, the first external electrode 200 and the second external electrode 300 may be positioned outside the laminate 100.

[0122] Referring to FIG. 5, the first external electrode 200 is connected to the positive electrode layer 130 and the solid electrolyte layer 110 on the fifth surface S5 of the laminate 100. For example, the first external electrode 200 may cover the fifth surface S5 of the laminate 100, and the first external electrode 200 may extend onto the first surface S1, the second surface S2, the third surface S3, and the fourth surface S4 of the laminate 100, to partially cover the respective surfaces.

[0123] The first external electrode 200 may be formed by baking a conductive paste. For example, the conductive paste may include glass and a metal such as silver (Ag) or copper (Cu).

[0124] Referring to FIG. 6, the second external electrode 300 may be connected to the negative electrode layer 150 and the solid electrolyte layer 110 on the sixth surface S6 of the laminate 100. For example, the second external electrode 300 may cover the sixth surface S6 of the laminate 100, and the second external electrode 300 may extend onto the first surface S1, the second surface S2, the third surface S3, and the fourth surface S4 of the laminate 100, to partially cover the respective surfaces.

[0125] The second external electrode 300 may be formed by baking a conductive paste. For example, the conductive paste may include glass and a metal such as silver (Ag) or copper (Cu).

[0126] For example, the fifth surface S5 and the sixth surface S6 of the laminate 100 are dipped into the conductive paste and then blotted to form the first external electrode 200 and the second external electrode 300. As another example, the conductive paste may be applied to the fifth surface S5 and the sixth surface S6 of the laminate 100, to form the first external electrode 200 and the second external electrode 300. As still another example, a dry film obtained by drying a conductive paste may be transferred to the laminate 100 and then baked, to form the first external electrode 200 and the second external electrode 300, but the forming method of the first external electrode 200 and the second external electrode 300 is not limited to the above-described method. For example, the conductive metal in the conductive paste may include at least one of copper (Cu), nickel (Ni), tin (Sn), palladium (Pd), platinum (Pt), gold (Au), silver (Ag), tungsten (W), titanium (Ti), lead (Pb), or their alloys, but is not limited to these.

[0127] FIG. 11 is a perspective view schematically illustrating the all-solid-state battery according to another embodiment, and FIG. 12 is a top plan view showing the all-solid-state battery of FIG. 11, and FIG. 13 is a bottom view showing the all-solid-state battery of FIG. 11. In addition, FIG. 14 is a cross-sectional view taken along line III-III' of FIG. 12, and FIG. 15 is a cross-sectional view taken along line IV-IV' of FIG. 12.

[0128] Referring to FIG. 11, FIG. 12, FIG. 13, FIG. 14, and FIG. 15, an all-solid-state battery 2000 may include a laminate 1100, a first external electrode 1200, a second external electrode 1300, a first insulation layer 910 and a second insulation layer 920.

[0129] The laminate 1100 may have a partial doughnut shape or a partial ring shape, and may include the solid electrolyte layer 110, the positive electrode layer 130, and the negative electrode layer 150.

[0130] The first external electrode 1200 may include a first connection portion 1210 and a first lead-out portion 1220.

[0131] The first connection portion 1210 may be disposed on the fifth surface S5 of the laminate 1100, and connected to the positive electrode layer 130 and the solid electrolyte layer 110.

[0132] For example, the first connection portion 1210 may be a thin film of metal. For example, the first connection portion 1210 may be formed by forming a thin film of metal on the fifth surface S5 of the laminate 1100 by a sputter process. Here, the thin film of metal may include Pt, Ag, Au, Ni, Cr, or a combination thereof.

[0133] As another example, the first connection portion 1210 may be formed by baking a conductive paste. The conductive paste may include, for example, glass and a conductive metal such as silver (Ag) or copper (Cu).

[0134] One end of the first connection portion 1210 in the thickness direction (z-axis direction) may be spaced apart from the first surface S1 of the laminate 1100. For example, the first connection portion 1210 may expose a portion of the upper protective layer 160 or the uppermost solid electrolyte layer 110 on the fifth surface S5.

[0135] The other end of the first connection portion 1210 in the thickness direction (z-axis direction) may extend to the second surface S2. Specifically, the first connection portion 1210 may entirely cover the lower protective layer 170 on the fifth surface S5.

[0136] The first lead-out portion 1220 may extend from the first connection portion 1210 onto the second surface S2 of the laminate 1100. The first lead-out portion 1220 may cover a portion of the second surface S2 of the laminate 1100.

[0137] The first lead-out portion 1220 may be formed by baking a conductive paste. The conductive paste may include, for example, glass and a conductive metal such as silver (Ag) or copper (Cu).

[0138] The first insulation layer 910 may cover a portion of the upper protective layer 160 and the first connection portion 1210 on the fifth surface S5 of the laminate 1100.

[0139] The first insulation layer 910 may include a ceramic material. For example, the first insulation layer 910 may include alumina (Al2O3), aluminum nitride (AlN), beryllium oxide (BeO), boron nitride (BN), silicon (Si), silicon carbide (SiC), silica (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, or any other suitable ceramic materials, but the present embodiment is not limited thereto.

[0140] The second external electrode 1300 may include a second connection portion 1310 and a second lead-out portion 1320.

[0141] The second connection portion 1310 may be disposed on the sixth surface S6 of the laminate 1100, and connected to the negative electrode layer 150 and the solid electrolyte layer 110.

[0142] For example, the second connection portion 1310 may be a thin film of metal. For example, the second connection portion 1310 may be formed by forming a thin film of metal on the sixth surface S6 of the laminate 1100 by a sputter process. Here, the thin film of metal may include Pt, Ag, Au, Ni, Cr, or a combination thereof.

[0143] As another example, the second connection portion 1310 may be formed by baking a conductive paste. The conductive paste may include, for example, glass and a conductive metal such as silver (Ag) or copper (Cu).

[0144] One end of the second connection portion 1310 in the thickness direction (z-axis direction) may be spaced apart from the first surface S1 of the laminate 1100. For example, the second connection portion 1310 may expose a portion of the upper protective layer 160 or the uppermost solid electrolyte layer 110 or on the sixth surface S6.

[0145] The other end of the second connection portion 1310 in the thickness direction (z-axis direction) may extend to the second surface S2. Specifically, the second connection portion 1310 may cover the lower protective layer 170 on the sixth surface S6.

[0146] The second lead-out portion 1320 may extend from the second connection portion 1310 onto the second surface S2 of the laminate 1100. The second lead-out portion 1320 may cover a portion of the second surface S2 of the laminate 1100.

[0147] The second lead-out portion 1320 may be formed by baking a conductive paste. The conductive paste may include, for example, glass and a conductive metal such as silver (Ag) or copper (Cu).

[0148] The second insulation layer 920 may cover a portion of the upper protective layer 160 and the second connection portion 1310 on the sixth surface S6 of the laminate 1100.

[0149] The second insulation layer 920 may include a ceramic material. For example, the second insulation layer 920 may include alumina (Al2O3), aluminum nitride (AlN), beryllium oxide (BeO), boron nitride (BN), silicon (Si), silicon carbide (SiC), silica (SiO2), silicon nitride (Si3N4), gallium arsenide (GaAs), nitride gallium (GaN), barium titanate (BaTiO3), zirconium dioxide (ZrO2), mixtures thereof, oxides and / or nitrides of these materials, or any other suitable ceramic materials, but the present embodiment is not limited thereto.

[0150] Remaining components other than the above are the same as or correspond to the components of the all-solid-state battery represented in FIG. 1, and repeated description thereon will be omitted.

[0151] FIG. 16 is a perspective view schematically showing a ring-shaped wearable electronic device on which the all-solid-state battery according to an embodiment is mounted.

[0152] Referring to FIG. 16, the all-solid-state battery 1000 may be mounted inside a ring-shaped wearable electronic device 3000. As with other components 3100, the shape of the all-solid-state battery 1000 corresponds to the shape of the ring-shaped wearable electronic device 3000, so that the all-solid-state battery 1000 may be mounted on the ring-shaped wearable electronic device 3000 without wasting space.

[0153] While this disclosure has been described in connection with what are presently considered practical embodiments, it is understood that the disclosure is not limited to these embodiments. On the contrary, it is intended to cover various modifications and equivalent arrangements within the spirit and scope of the appended claims.

[0154] <Description of symbols>

[0155] 1000, 2000: all-solid-state battery

[0156] 100, 1100: laminate

[0157] 110: solid electrolyte layer

[0158] 130: positive electrode layer

[0159] 150: negative electrode layer

[0160] 160: upper protective layer

[0161] 170: lower protective layer

[0162] 180: margin portion

[0163] 200, 1200: first external electrode

[0164] 300, 1300: second external electrode

[0165] 910: first insulation layer

[0166] 920: second insulation layer

Claims

1.An all-solid-state battery, comprising:a laminate comprising a positive electrode layer, a solid electrolyte layer, and a negative electrode layer that are stacked in a first direction;a first external electrode disposed outside the laminate and connected to the positive electrode layer; anda second external electrode disposed outside the laminate and connected to the negative electrode layer,wherein the positive electrode layer comprises a positive electrode current collector and a positive electrode active material layer disposed on the positive electrode current collector and in contact with the solid electrolyte layer,wherein the negative electrode layer comprises a negative electrode current collector and a negative electrode active material layer disposed on the negative electrode current collector and in contact with the solid electrolyte layer, andwherein the laminate is curved in a second direction intersecting the first direction.2.The all-solid-state battery of claim 1, wherein the laminate has a curvature.3.The all-solid-state battery of claim 2, wherein:the laminate comprises a first surface and a second surface disposed opposite each other in the second direction;the first surface has a first radius of curvature; andthe second surface has a second radius of curvature.4.The all-solid-state battery of claim 3, wherein the first radius of curvature is smaller than the second radius of curvature.5.The all-solid-state battery of claim 4, wherein, when viewed in the first direction, the first surface and the second surface form a circular arc shape or an elliptical arc shape.6.The all-solid-state battery of claim 4, wherein, when viewed in the first direction, the first surface and the second surface form portions of concentric circles.7.The all-solid-state battery of claim 2, wherein the positive electrode layer, the solid electrolyte layer, and the negative electrode layer have curvatures conforming to the laminate, respectively.8.The all-solid-state battery of claim 3, wherein:the laminate comprises a first end surface and a second end surface disposed opposite each other along a third direction intersecting with the first direction and the second direction and extending between the first surface and the second surface;the first external electrode is disposed on the first end surface; andthe second external electrode is disposed on the second end surface.9.The all-solid-state battery of claim 8, wherein:the laminate comprises a third surface and a fourth surface disposed opposite each other in the first direction;the first external electrode extends from the first end surface to cover a portion of the third surface and a portion of the fourth surface; andthe second external electrode extends from the second end surface to cover a portion of the third surface and a portion of the fourth surface.10.The all-solid-state battery of claim 3, wherein:the laminate comprises: a first end surface and a second end surface disposed opposite each other along a third direction intersecting with the first direction and the second direction and extending between the first surface and the second surface; and a third surface and a fourth surface positioned opposite each other along the first direction;the first external electrode comprises a first connection portion disposed on the first end surface and a first lead-out portion connected to the first connection portion and positioned on the fourth surface; andthe second external electrode comprises a second connection portion disposed on the second end surface and a second lead-out portion connected to the second connection portion and positioned on the fourth surface.11.The all-solid-state battery of claim 10, further comprising:a first insulation layer covering the first connection portion on the first end surface; anda second insulation layer covering the second connection portion on the second end surface.12.An all-solid-state battery comprising:a laminate comprising a positive electrode layer, a solid electrolyte layer, and a negative electrode layer stacked in a first direction;a margin portion disposed along edges of the positive electrode layer and the negative electrode layer,a first external electrode disposed on a first end surface of the laminate and connected to the positive electrode layer;a second external electrode disposed on a second end surface of the laminate and connected to the negative electrode layer; anda first insulation layer covering the first external electrode on the first end surface and a second insulation layer covering the second external electrode on the second end surface,wherein the margin portion is made of an insulating material with low ionic conductivity.13.The all-solid-state battery of claim 12, wherein the margin portion comprises a material selected from a group consisting of alumina (Al₂O₃), silicon carbide (SiC), boron nitride (BN), and zirconium dioxide (ZrO₂).14.The all-solid-state battery of claim 13, wherein the margin portion has an ionic conductivity of 1.0 × 10-10S / cm or less.

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