Composite solid electrolyte and all-solid-state battery including same

Abstract

A composite solid electrolyte according to the present disclosure includes a garnet-type solid electrolyte and a Li super-ionic conductor-type solid electrolyte containing a Cl element. The present invention relates to a solid electrolyte for a lithium ion battery, the solid electrolyte being represented by LiaMbPcCldOe, where M includes Zn, Al, Ga, Si, Ge, Ti, Mg, or a combination thereof, a, b, c, d, and e are molar ratios of the components, and satisfy 5 < = a < = 12, 0lt; b < = 3, 0lt; c < = 3, 0lt; d < = 0.1 and 10 < = e < = 12.

Description

Technical Field

[0001] The present disclosure relates to a composite solid electrolyte and an all-solid-state battery including the composite solid electrolyte. Background Art

[0002] Recently, the need for portable electronic devices to be miniaturized and used for extended periods of time has necessitated the demand for high-capacity batteries. Furthermore, the widespread use of wearable electronic devices has also led to demands for battery safety. Consequently, the development of all-solid-state batteries, which use solid electrolytes instead of liquid electrolytes, is actively progressing.

[0003] Since all-solid-state batteries do not use flammable organic solvents, additional circuitry for safety can be simplified. Therefore, all-solid-state batteries are expected to be a technology that can produce safe batteries with high capacity per unit volume.

[0004] In addition, compared with sulfide all-solid-state batteries that use sulfide electrolytes that react oxygen and moisture in the air, the use of sulfide electrolytes with ionic conductivity (10 -2 S / cm) lower ionic conductivity (10 -4 S / cm to 10 - 6 S / cm) oxide all-solid-state batteries require a high-temperature sintering process but exhibit excellent stability.

[0005] Compared to lithium metal (vs. Li / Li+), oxide electrolytes typically use materials containing vanadium (V), which has the problem of causing redox reactions in the voltage range of 0.5 V to 1.5 V. This redox reaction of vanadium is a side reaction, which makes it difficult for all-solid-state batteries to operate normally, and therefore all-solid-state batteries can only operate in the voltage range of 1.5 V or higher.

[0006] In addition, garnet-type electrolyte, as a conventional oxide electrolyte, also has the disadvantages of high relative density and high firing temperature. Summary of the Invention

[0007] Solutions to the Problem An aspect of an embodiment provides a composite solid electrolyte that can reduce a firing temperature, does not cause side reactions within an operating voltage range of 0 V to 6 V, has a high relative density, and has high lithium ion conductivity.

[0008] Another aspect of the embodiment provides an all-solid-state battery including the composite solid electrolyte.

[0009] However, the problems to be solved by the embodiments are not limited to the above-mentioned problems, and various extensions can be made within the scope of the technical ideas included in the embodiments.

[0010] Advantageous Effects of the Invention Based on the composite solid electrolyte according to the embodiment, the firing temperature can be reduced, side reactions do not occur within the operating voltage range of 0 V to 6 V, the relative density is high, and the lithium ion conductivity is high.

[0011] The all-solid-state battery including the composite solid electrolyte has the advantage of being able to be driven within all operating voltage ranges of 0 V to 6 V because side reactions do not occur within the operating voltage range of 0.75 V to 1.5 V. In addition, since there is no need to avoid the side reaction range, there is an advantage of expanding the types of electrode active materials that can be selected.

[0012] However, the various advantageous advantages and effects of the present invention are not limited to the above description, and will be more easily understood during the process of describing the specific embodiments of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 is a perspective view schematically showing an all-solid-state battery according to an embodiment.

[0014] Figure 2 is Figure 1 a cross-sectional view of the all-solid-state battery according to the embodiment shown in

[0015] Figure 3 is a perspective exploded view schematically showing Figure 1 the unit cell stacking structure of the all-solid-state battery according to the embodiment shown in

[0016] Figure 4 is a diagram showing the side reaction analysis results of Example 1, Example 2, Comparative Example 9, and Comparative Example 10.

[0017] BEST MODE FOR CARRYING OUT THE INVENTION A composite solid electrolyte according to an embodiment includes: a garnet-type solid electrolyte; and a Li superionic conductor-type solid electrolyte containing a Cl element. The Li superionic conductor-type solid electrolyte is represented by Chemical Formula 1.

[0018] [Chemical Formula 1] Li a M b P c Cl d O e M includes Zn, Al, Ga, Si, Ge, Ti, Mg, or a combination thereof, and a, b, c, d, and e are the molar ratios of the respective components, and satisfy 5 ≤ a ≤ 12, 0 < b ≤ 3, 0 < c ≤ 3, 0 < d ≤ 0.1, and 10 ≤ e ≤ 12.

[0019] M may include Si (silicon) or Ge (germanium).

[0020] M may not include V (vanadium).

[0021] The composite solid electrolyte may further include an oxide including Li element and B element.

[0022] The oxide containing the Li element and the B element may include Li 3 BO 3 , Li 4 B 2 O 5 , LiBO 2 , or a combination thereof.

[0023] The garnet-type solid electrolyte may be included in an amount of 10 volume % to 50 volume % based on the total volume of the composite solid electrolyte.

[0024] The Li super ion conductor-type solid electrolyte may be included in an amount of 40 volume % to 80 volume % based on the total volume of the composite solid electrolyte.

[0025] The oxide including the Li element and the B element may be included in an amount of 5 volume % to 20 volume % based on the total volume of the composite solid electrolyte.

[0026] A volume ratio of the garnet-type solid electrolyte to the Li superion conductor-type solid electrolyte may be 10:80 to 45:45.

[0027] The volume ratio of the sum of the garnet-type solid electrolyte and the Li superion conductor-type solid electrolyte to the oxide containing the Li element and the B element may be 80:20 to 90:10.

[0028] The composite solid electrolyte may have a relative density (%) greater than or equal to 80%.

[0029] The composite solid electrolyte may have a thickness greater than or equal to 1×10 -7 (S / cm) of lithium ion conductivity at room temperature (25°C).

[0030] Li a M b P c Cl d O e Can include Li 10.42 Si 1.5 P 1.5 Cl 0.08 O 11.92 .

[0031] A all-solid-state battery according to another embodiment includes: a solid electrolyte layer; and a positive electrode layer and a negative electrode layer, with the solid electrolyte layer disposed between the positive electrode layer and the negative electrode layer. The solid electrolyte layer includes a composite solid electrolyte, and the composite solid electrolyte includes a garnet (LLZO) type solid electrolyte and a Cl element as well as a Li superionic conductor solid electrolyte, and the Li superionic conductor type solid electrolyte is represented by Chemical Formula 1.

[0032] [Chemical Formula 1] Li a M b P c Cl d O e M includes Zn, Al, Ga, Si, Ge, Ti, Mg, or a combination thereof, and a, b, c, d, and e are the molar ratios of the respective components and satisfy 5 ≤ a ≤ 12, 0 < b ≤ 3, 0 < c ≤ 3, 0 < d ≤ 0.1, and 10 ≤ e ≤ 12.

[0033] The composite solid electrolyte may further include an oxide containing Li element and B element.

[0034] A all-solid-state battery according to another embodiment includes: a stack including a plurality of solid electrolyte layers and a plurality of positive electrode layers and a plurality of negative electrode layers, with the positive electrode layer and the negative electrode layer alternating and the plurality of solid electrolyte layers disposed therebetween; and a first external electrode and a second external electrode, respectively disposed on one surface of the stack and on another surface opposite to the one surface, and respectively connected to the positive electrode layer and the negative electrode layer. The solid electrolyte layer includes a composite solid electrolyte, and the composite solid electrolyte includes a garnet (LLZO) type solid electrolyte and a Li superionic conductor type solid electrolyte containing a Cl element, and the Li superionic conductor type solid electrolyte is represented by Chemical Formula 1.

[0035] [Chemical Formula 1] Li a M b P c Cl d O e M includes Zn, Al, Ga, Si, Ge, Ti, Mg, or a combination thereof, and a, b, c, d, and e are the molar ratios of the respective components and satisfy 5 ≤ a ≤ 12, 0 < b ≤ 3, 0 < c ≤ 3, 0 < d ≤ 0.1, and 10 ≤ e ≤ 12.

[0036] The composite solid electrolyte may further include an oxide containing Li element and B element. DETAILED DESCRIPTION

[0037] Hereinafter, various embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily implement the present invention. The drawings and descriptions are considered to be illustrative rather than restrictive in nature. Throughout the specification, the same reference numerals represent the same elements. In addition, the drawings are provided only to allow easy understanding of the embodiments disclosed in this specification, and the drawings should not be interpreted as limiting the spirit disclosed in this specification, and it should be understood that the present invention includes all variations, equivalents and alternatives without departing from the scope and spirit of the present invention. In addition, some of the constituent elements in the drawings are exaggerated, omitted or schematically shown, and the size of each constituent element does not fully reflect the actual size.

[0038] In addition, 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.

[0039] Throughout this specification, the term "stacking direction" refers to the direction in which components are stacked sequentially, or the "thickness direction" perpendicular to the major surface (main surface) of a sheet-like component. This corresponds to the T-axis in the drawings. Furthermore, the term "lateral direction" refers to the direction extending parallel to the major surface (main surface) from the edge of a sheet-like component, or the "planar direction," which corresponds to the L-axis in the drawings. Furthermore, the W-axis in the drawings may be referred to as the "width direction."

[0040] Hereinafter, various embodiments and modifications will be described in detail with reference to the accompanying drawings.

[0041] The composite solid electrolyte according to the embodiment includes a garnet-type solid electrolyte and a LISICON-type solid electrolyte containing a Cl element.

[0042] Garnet-type solid electrolyte is an oxide-based solid electrolyte and has advantages over Li metal in having high lithium ion conductivity and high stability even at high temperatures.

[0043] Garnet-type solid electrolytes may refer to those composed of Li x La y Zr z A w O 12 Represents lithium-lanthanum-zirconium oxide (LLZO).

[0044] A may include Ga, Gd, Al, Mg, Zn, Sc, Nb, Ta, Bi, or a combination thereof.

[0045] x, y, z, and w are the molar ratios of the respective components and can be 6 < x ≤ 7, 2 < y ≤ 3, 1.5 < z ≤ 2, and 0 ≤ w ≤ 0.5. For example, the garnet-type solid electrolyte may include Li7La3Zr2O 12 , Li 6.25 Al 0.25 La3Zr2O 12 , Li 6.4 Ga 0.2 La3Zr2O 12 , Li 6.75 La3Zr 1.75 Nb 0.25 O 12 , Li 6.75 La3Zr 1.75 Ta 0.25 O 12 , Li 6.75 La3Zr 1.75 Al 0.25 O 12 or Li 6.4 Ga 0.2 La 2.95 Ga 0.05 Zr2O 12 .

[0046] The LISICON-type (Li superionic conductor) solid electrolyte is an oxide containing Cl element.

[0047] For example, the LISICON-type solid electrolyte may be an oxide containing Li element, Si element, Ge element, P element, and Cl element.

[0048] For example, the LISICON-type solid electrolyte is represented by Chemical Formula 1.

[0049] [Chemical Formula 1] Li a M b P c Cl d O e M includes Zn, Al, Ga, Si, Ge, Ti, Mg, or a combination thereof.

[0050] For example, M may include Si (silicon) or Ge (germanium), and for example, M may not include V (vanadium).

[0051] a, b, c, d, and e are the molar ratios of the respective components, 5 ≤ a ≤ 12, 0 < b ≤ 3, 0 < c ≤ 3, 0 < d ≤ 0.1, and 10 ≤ e ≤ 12.

[0052] In Chemical Formula 1, it may satisfy 10 ≤ a ≤ 12 or 10 ≤ a ≤ 11.

[0053] In Chemical Formula 1, 1≤b≤3 or 1≤b≤1.5 may be satisfied.

[0054] In Chemical Formula 1, 1≤c≤3 or 1≤c≤1.5 may be satisfied.

[0055] In Chemical Formula 1, 0.05≤d≤0.1 may be satisfied.

[0056] In Chemical Formula 1, 11≤e≤12 or 11.5≤e≤12 may be satisfied.

[0057] For example, in Chemical Formula 1, 0 may be satisfied. <d+e≤12。

[0058] For example, a LISICON-type solid electrolyte may include Li 10.42 Ge 1.5 P 1.5 Cl 0.08 O 11.92 or Li 10.42 Si 1.5 P 1.5 Cl 0.08 O 11.92 , and as a more specific example, may include Li 10.42 Si 1.5 P 1.5 Cl 0.08 O 11.92 For example, a LISICON-type solid electrolyte may not include Li 3.2 (V 0.8 Si 0.2 )O4 containing V (vanadium) LISICON type solid electrolyte.

[0059] Because the LISICON-type solid electrolyte is doped with Cl, the lithium ion conductivity is particularly high and the side reactions that hinder battery driving can be suppressed.

[0060] In addition, since the LISICON type solid electrolyte does not contain the V element, oxidation / reduction reaction of the V element does not occur even when the battery is driven, and side reactions can be suppressed.

[0061] The composite solid electrolyte according to the embodiment may further include an oxide containing Li and B. The oxide containing Li and B may be a material added to adjust the process temperature to a low temperature during the firing process. The oxide containing Li and B may include Li3BO3, Li4B2O5, LiBO2, or a combination thereof, and specifically, may include Li3BO3.

[0062] The garnet-type solid electrolyte may be included in an amount of 10 to 50 volume % or 20 to 45 volume % based on the total composite solid electrolyte. When the garnet-type solid electrolyte is included in an amount of less than 10 volume % based on the total composite solid electrolyte, the lithium ion conductivity may be reduced, and when the garnet-type solid electrolyte is included in an amount of more than 50 volume %, the relative density of the composite solid electrolyte may be reduced.

[0063] The LISICON-type solid electrolyte may be included in an amount of 40% to 80% by volume or 45% to 65% by volume based on the total composite solid electrolyte. When the LISICON-type solid electrolyte is included in an amount of less than 40% by volume based on the total composite solid electrolyte, sinterability may be deteriorated, and when the LISICON-type solid electrolyte is included in an amount of more than 80% by volume, the ion conductivity of the composite solid electrolyte may be reduced.

[0064] The oxide containing the Li element and the B element may be included in an amount of 5% to 20% by volume or 10% to 15% by volume based on the total composite solid electrolyte. When the oxide containing the Li element and the B element is included in an amount of less than 5% by volume based on the total composite solid electrolyte, it is difficult to lower the firing temperature, and when the oxide containing the Li element and the B element is included in an amount of more than 20% by volume, the lithium ion conductivity decreases.

[0065] The volume ratio of the garnet-type solid electrolyte to the LISICON-type solid electrolyte may be 10:80 to 45:45 or 20:70 to 45:45 based on the total composite solid electrolyte.

[0066] The volume ratio of the sum of the garnet-type solid electrolyte and the LISICON-type solid electrolyte to the oxide including the Li element and the B element may be 80:20 to 90:10 or 85:15 to 90:10 based on the total composite solid electrolyte.

[0067] The volume ratio of the garnet-type solid electrolyte, the LISICON-type solid electrolyte, and the oxide containing the Li element and the B element may be, for example, 45:45:10 based on the entire composite solid electrolyte.

[0068] For example, the composite solid electrolyte may include a garnet-type solid electrolyte, Li 10.42 Si 1.5 P 1.5 Cl 0.08 O 11.92 and Li3BO3.

[0069] For example, the composite solid electrolyte may include a garnet-type solid electrolyte, Li 10.42 Si1.5 P 1.5 Cl 0.08 O 11.92 and Li3BO3.

[0070] The relative density (%) of the composite solid electrolyte according to the embodiment may be greater than or equal to 80%.

[0071] The relative density (%) is calculated by dividing the apparent density by the true density, and the apparent density can be calculated using the volume and apparent volume of the material, and the true density can be obtained from single crystal X-ray structural analysis results.

[0072] When the relative density (%) of the composite solid electrolyte satisfies the above range, the solid electrolyte layer included in the all-solid-state battery may have a relative density greater than or equal to 1×10 -7 (S / cm) ion conductivity.

[0073] The lithium ion conductivity of the composite solid electrolyte according to the embodiment may be greater than or equal to 1×10 -7 (S / cm), and for example, greater than or equal to 5×10 -7 (S / cm).

[0074] The lithium ion conductivity of a composite solid electrolyte can be measured using the alternating current (AC) impedance method. First, the solid electrolyte layer in an all-solid-state battery is exposed by ion milling or polishing, and a portion of the solid electrolyte layer is sampled into a rectangular plate-like piece. Subsequently, electrodes made of gold (Au) are formed on both ends of the obtained piece to prepare a sample. Then, an impedance measurement device (frequency: from 10 +6 Hz to 10 -1 The AC impedance of the sample was measured at room temperature (25°C) to calculate the ionic conductivity.

[0075] Based on the composite solid electrolyte according to the embodiment, the firing temperature can be lowered, no side reaction occurs within the operating voltage range of 0 V to 6 V, the relative density is high, and the lithium ion conductivity is high.

[0076] An all-solid-state battery according to an embodiment includes: a solid electrolyte layer; a positive electrode layer and a negative electrode layer, the solid electrolyte layer is provided between the positive electrode layer and the negative electrode layer, and the solid electrolyte layer includes a composite solid electrolyte.

[0077] A all-solid-state battery according to another embodiment includes: a stack including a plurality of solid electrolyte layers, a plurality of positive electrode layers, and a plurality of negative electrode layers, the positive electrode layers and the negative electrode layers being alternately arranged with the plurality of solid electrolyte layers disposed therebetween; and a first external electrode and a second external electrode respectively disposed on one surface and the other surface opposite to the one surface of the stack and respectively connected to the positive electrode layers and the negative electrode layers. The solid electrolyte layer includes a composite solid electrolyte.

[0078] The composite solid electrolyte includes a garnet (LLZO) type solid electrolyte and a LISICON type solid electrolyte containing Cl element, and the LISICON type solid electrolyte is represented by Chemical Formula 1.

[0079] [Chemical Formula 1] Li a M b P c Cl d O e M includes Zn, Al, Ga, Si, Ge, Ti, Mg, or a combination thereof, and a, b, c, d, and e are the molar ratios of the respective components, where 5 ≤ a ≤ 12, 0 < b ≤ 3, 0 < c ≤ 3, 0 < d ≤ 0.1, and 10 ≤ e ≤ 12.

[0080] The composite solid electrolyte may further include an oxide containing Li element and B element.

[0081] Since the composite solid electrolyte is the same as described above, its detailed description will be omitted.

[0082] Figure 1 is a perspective view schematically showing the all-solid-state battery according to an embodiment, Figure 2 is Figure 1 a cross-sectional view of the all-solid-state battery according to an embodiment shown in Figure 3 is schematically showing Figure 1 an exploded perspective view of the unit cell stack structure of the all-solid-state battery shown in

[0083] The all-solid-state battery 100 may have, for example, an approximately hexahedral shape.

[0084] The all-solid-state battery 100 according to an embodiment includes electrode layers 120 and 140 and a solid electrolyte layer 130 adjacent to the electrode layers 120 and 140 in the stacking direction. The electrode layers 120 and 140 include a positive electrode layer 120 and a negative electrode layer 140, and mainly include current collectors 123 and 143 and active material layers 121, 122, 141, and 142 coated on at least one surface of the current collectors 123 and 143.

[0085] The positive electrode layer 120 is formed by coating positive electrode active material layers 121 and 122 on at least one surface of a positive electrode collector 123, and the negative electrode layer 140 is formed by coating negative electrode active material layers 141 and 142 on at least one surface of a negative electrode collector 143. For example, in the stacking direction, the uppermost electrode layer is formed by coating the positive electrode active material layer 122 on one surface of the positive electrode collector 123, and the lowermost electrode layer can be formed by coating the negative electrode active material layer 141 on one surface of the negative electrode collector 143. Furthermore, the electrode layers between the uppermost and lowermost ends are formed by coating the positive electrode active material layers 121 and 122 on both surfaces of the positive electrode collector 123 or forming the negative electrode active material layers 141 and 142 on both surfaces of the negative electrode collector 143.

[0086] The positive electrode active material layers 121 and 122 may include a positive electrode active material and, optionally, a solid electrolyte. In addition, the positive electrode active material layers 121 and 122 may further include an additive such as a binder or a conductive agent.

[0087] For example, the positive electrode active material is not particularly limited as long as it can ensure sufficient capacity of the all-solid-state battery 100. For example, the positive electrode active material may include lithium cobalt oxide, lithium nickel cobalt manganese oxide, lithium nickel cobalt aluminum oxide, lithium iron phosphate, lithium manganese oxide, or a combination thereof.

[0088] For example, the positive electrode active material may be a compound represented by the following chemical formula: Li a A l-b M b D2 (where 0.90≤a≤1.8, 0≤b≤0.5); Li a E l-b M b O 2-c D c (where 0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.05); LiE 2-b M b O 4-c D c (where 0≤b≤0.5, 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, 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, 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, 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, 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, 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, 0<α<2); Li a Ni b E c G d O2 (where 0.90≤a≤1.8, 0≤b≤0.9, 0≤c≤0.5, 0.001≤d≤0.1); Li a Ni b Co c Mn d GeO2 (where 0.90≤a≤1.8, 0≤b≤0.9, 0≤c≤0.5, 0≤d≤0.5, 0.001≤e≤0.1); Li a NiGbO2 (where 0.90≤a≤1.8, 0.001≤b≤0.1); Li a CoGbO2 (where 0.90≤a≤1.8, 0.001≤b≤0.1); Li a MnGbO2 (where 0.90≤a≤1.8, 0.001≤b≤0.1); Li a Mn2GbO4 (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 (wherein 0≤f≤2); and LiFePO4, wherein, in the above chemical formula, A is Ni, Co or Mn; M is Al, Ni, Co, Mn, Cr, Fe, Mg, Sr, V or a 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; and J is V, Cr, Mn, Co, Ni or Cu.

[0089] The positive electrode active material can also be LiCoO2, LiMn x O 2x (where x = 1 or 2), LiNi 1-x Mn x O 2x (where 0<x<1), LiNi 1-x-y Co x Mn y O2 (wherein, 0≤x≤0.5, 0≤y≤0.5), LiFePO4, TiS2, FeS2, TiS3 or FeS3.

[0090] The positive electrode layer 120 may further include a solid electrolyte. The type of solid electrolyte included in the positive electrode layer 120 is not particularly limited, but may include the same type of solid electrolyte as the composite solid electrolyte described above. The content of the solid electrolyte may be greater than or equal to 0.1 parts by weight, greater than or equal to 1 part by weight, or greater than or equal to 10 parts by weight, and less than or equal to 80 parts by weight, less than or equal to 60 parts by weight, or less than or equal to 50 parts by weight, based on 100 parts by weight of the total amount of the positive electrode active material.

[0091] The conductive agent is not particularly limited as long as it has conductivity without causing chemical changes in the all-solid-state battery 100. For example, examples of the conductive agent may include: 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 black; conductive fibers, such as carbon fibers and metal fibers; fluorocarbons; metal powders, such as aluminum powder and nickel powder; conductive whiskers, such as zinc oxide and potassium titanate; conductive metal oxides, such as titanium oxide; or conductive materials, such as polyphenylene derivatives.

[0092] Based on 100 parts by weight of the positive electrode active material, the conductive agent may be present in an amount of 1 to 10 parts by weight, or for example, 2 to 5 parts by weight. When the conductive agent content is within the above range, the resulting electrode may have excellent conductive properties.

[0093] Binders can be used to improve the bond strength between the active material and the conductive agent. Binders can include polyvinylidene fluoride, polyvinyl alcohol, carboxymethyl cellulose (CMC), starch, hydroxypropyl cellulose, regenerated cellulose, polyvinyl pyrrolidone, polytetrafluoroethylene, polyethylene, polypropylene, ethylene-propylene-diene terpolymer (EPDM), sulfonated EPDM, styrene-butadiene rubber, fluororubber, or various copolymers.

[0094] The binder may be present in an amount of 1 to 50 parts by weight, or 2 to 5 parts by weight, based on 100 parts by weight of the total positive active material.

[0095] The positive electrode current collector 123 is not particularly limited, as long as it is conductive without causing chemical changes to the positive electrode or the battery. For example, examples of the positive electrode current collector may include: 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 black; and conductive fibers, such as carbon fibers or metal fibers. In addition, porous materials such as those in a grid or mesh shape can be used as the positive electrode current collector, and porous metal plates such as stainless steel, nickel, or aluminum can be used. Furthermore, the positive electrode current collector 123 may be coated with an anti-oxidant metal or alloy film to prevent oxidation.

[0096] The negative electrode active material layers 141 and 142 may include a negative electrode active material, and optionally, may include a solid electrolyte.

[0097] The negative electrode active material may be 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, and may include lithium metal and / or lithium metal alloy.

[0098] The lithium metal alloy may include lithium and a metal / semimetal capable of alloying with lithium. For example, the metal / semimetal capable of alloying with lithium may include Si, Sn, Al, Ge, Pb, Bi, Sb, Si-Y alloy (wherein Y is an alkali metal, an alkaline earth metal, an element from Group 13 to Group 16, a transition metal, a rare earth element, or a combination thereof, and does not include Si), Sn-Y alloy (wherein Y is an alkali metal, an alkaline earth metal, an element from Group 13 to Group 16, a transition metal, such as lithium titanium oxide (Li4Ti5O 12 ) transition metal oxides, rare earth elements or combinations thereof, and excluding Sn) or MnO x (0 <x≤2)。

[0099] Element Y may be 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.

[0100] In addition, the oxide of a metal / semimetal capable of alloying with lithium may be lithium titanium oxide, vanadium oxide, lithium vanadium oxide, SnO2, SiO x (0 < x < 2), etc. For example, the negative electrode active material may include one or more elements selected from the 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.

[0101] The carbon-based material may be crystalline carbon, amorphous carbon, or a mixture thereof. Crystalline carbon may include graphite, such as natural graphite or artificial graphite in irregular form, plate form, flake form, spherical form, or fibrous form. In addition, amorphous carbon may include soft carbon (low-temperature calcined carbon) or hard carbon, mesophase pitch carbonized product, calcined coke, graphene, carbon black, fullerene soot, carbon nanotubes, carbon fibers, etc.

[0102] Silicon may be Si, SiO x (0 < x < 2, for example 0.5 to 1.5), Sn, SnO2, a silicon-containing metal alloy, or a mixture thereof. The silicon-containing metal alloy may include, for example, one or more of Al, Sn, Ag, Fe, Bi, Mg, Zn, In, Ge, Pb, and Ti, as well as silicon.

[0103] The negative electrode layer 140 may further include a solid electrolyte. The type of the solid electrolyte included in the negative electrode layer 140 is not particularly limited, but may include the same type of solid electrolyte as the aforementioned composite solid electrolyte.

[0104] Optionally, the negative electrode active material layer may further include a conductive agent and an adhesive as described in the positive electrode active material layer.

[0105] The negative electrode current collector 143 is not particularly limited, as long as it is conductive without causing chemical changes in the negative electrode or the battery. Examples of negative electrode current collectors include: 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 black; and conductive fibers, such as carbon fibers or metal fibers. Porous materials, such as those in a grid or mesh form, can be used as the negative electrode current collector, as can porous metal sheets, such as stainless steel, nickel, or aluminum. Furthermore, the negative electrode current collector 143 can be coated with an anti-oxidant metal or alloy film to prevent oxidation.

[0106] The solid electrolyte layer 130 may be disposed and stacked between the positive electrode layer 120 and the negative electrode layer 140. Thus, the solid electrolyte layer 130 may be disposed adjacently between the positive electrode active material layers 121 and 122 of the positive electrode layer 120 and the negative electrode active material layers 141 and 142 of the negative electrode layer 140 in the stacking direction. Thus, in the all-solid-state battery 100, a plurality of positive electrode layers 120 and a plurality of negative electrode layers 140 may be alternately disposed, and a plurality of solid electrolyte layers 130 may be interposed and stacked therebetween. In the all-solid-state battery 100, a plurality of positive electrode layers 120 and a plurality of negative electrode layers 140 are alternately stacked with a plurality of solid electrolyte layers 130 interposed therebetween to produce a battery stack, which may then be batch fired to produce a stacked all-solid-state battery 100.

[0107] The solid electrolyte layer 130 includes the composite solid electrolyte described above. Since the composite solid electrolyte has been described in detail above, a description thereof will be omitted.

[0108] By including the composite solid electrolyte having the above-described excellent effects in the solid electrolyte layer 130, side reactions do not occur within the operating voltage range of 0.75 V to 1.5 V, thereby enabling driving within the entire operating voltage range of 0 V to 6 V. In addition, since there is no need to avoid the side reaction range, there is an advantage of expanding the types of selectable electrode active materials.

[0109] The edge layer 150 may be provided along the edges of the positive electrode layer 120 and the negative electrode layer 140. The edge layer 150 is provided on the solid electrolyte layer 130 and may be formed adjacent to the edges of the positive electrode active material layers 121 and 122 or the negative electrode active material layers 141 and 142 in the lateral direction. Therefore, the edge layer 150 may be provided on the same layer as the positive electrode layer 120 and on the same layer as the negative electrode layer 140.

[0110] The edge layer 150 may include a layer having a thickness less than or equal to 1.0×10 -10 S / cm, for example, an insulating material such as the aforementioned solid electrolyte material or resin.

[0111] For example, the insulating material may be polyolefin such as polyethylene or polypropylene, polyester such as polyethylene terephthalate (PET), polyurethane, or polyimide.

[0112] In addition, edge layer 150 may include an inorganic solid electrolyte including an oxide-based solid electrolyte, a sulfide-based solid electrolyte, or a combination thereof used in solid electrolyte layer 130. However, edge layer 150 is not limited thereto but may include various materials.

[0113] The positive electrode layer 120, the solid electrolyte layer 130, the negative electrode layer 140, and the edge layer 150 may be stacked as described above to form a battery stack of the all-solid-state battery 100. Protective layers (not shown) made of an insulating material may be formed on the upper and lower ends of the battery stack of the all-solid-state battery 100.

[0114] In addition, the ends of the positive current collector 123 and the negative current collector 143 are exposed on both sides of the battery stack of the all-solid-state battery 100, and the external electrodes 112 and 114 can be connected to and bonded to the exposed ends. That is, the external electrode 112 can be configured to be connected to the end of the positive current collector 123 to have a positive polarity, and the external electrode 114 can be connected to the end of the negative current collector 143 to have a negative polarity. When the ends of the positive current collector 123 and the ends of the negative current collector 143 are configured to face in opposite directions, the external electrodes 112 and 114 can also be provided on both sides, respectively.

[0115] The external electrodes 112 and 114 may include conductive metal and glass.

[0116] 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.

[0117] The glass component included in the external electrodes 112 and 114 may have a composition in which an oxide is mixed. The glass component may include, for example, silicon oxide, boron oxide, aluminum oxide, transition metal oxides, alkali metal oxides, alkaline earth metal oxides, or combinations thereof. Here, the transition metal may be selected from zinc (Zn), titanium (Ti), copper (Cu), vanadium (V), manganese (Mn), iron (Fe), or nickel (Ni), the alkali metal may be selected from lithium (Li), sodium (Na), or potassium (K), and the alkaline earth metal may be selected from magnesium (Mg), calcium (Ca), strontium (Sr), or barium (Ba).

[0118] There is no particular limitation on the method for forming the external electrodes 112 and 114. For example, the method may include immersing the battery stack in a conductive paste containing a conductive metal and glass, or screen printing or gravure printing the conductive paste on the surface of the battery stack. Alternatively, various methods may be used, such as coating the surface of the battery stack with the conductive paste or transferring a dry film obtained by drying the conductive paste onto the battery stack.

[0119] Hereinafter, specific examples of the present invention are presented. However, the examples described below are only intended to specifically illustrate or explain the present invention, and the scope of the present invention should not be limited thereto.

[0120] [Example] (Example 1) Li7La3Zr2O 12 (hereinafter referred to as LLZO), Li 10.42 Si 1.5 P 1.5 Cl 0.08 O 11.92 , and Li₃BO₃ were weighed and mixed in a volume ratio of 45:45:10. The mixture was mixed with a binder and a binder solvent, and then ball-milled at room temperature for 24 hours or longer to ensure thorough and uniform mixing. The solvent was dried in an oven to obtain a binder-coated mixed powder.

[0121] Subsequently, a solid electrolyte layer green sheet including a mixed composite solid electrolyte, a positive electrode layer green sheet, and a negative electrode layer green sheet are manufactured, stacked in the order of positive electrode layer green sheet - solid electrolyte layer green sheet - negative electrode layer green sheet, and heat treated at 250°C to 600°C in an oxygen atmosphere to remove the binder. After the binder is removed, the stack is fired at 800°C in an oxygen atmosphere to manufacture a unit cell.

[0122] (Example 2) A unit cell was manufactured in the same manner as in Example 1, except that the heat treatment was performed at 700°C.

[0123] (Example 3) In addition to the use of LLZO, Li 10.42 Si 1.5 P 1.5 Cl 0.08 O 11.92 A unit cell was manufactured in the same manner as in Example 1, except that a composite solid electrolyte was prepared by mixing Li 3 BO 3 and Li 3 BO 3 at a volume ratio of 20:65:15.

[0124] (Example 4) In addition to the use of LLZO, Li 10.42 Si 1.5 P 1.5Cl 0.08 O 11.92 A unit cell was manufactured in the same manner as in Example 1, except that a composite solid electrolyte was prepared by mixing Li 3 BO 3 and Li 3 BO 3 at a volume ratio of 75:15:10.

[0125] (Comparative Example 1) A unit cell was manufactured in the same manner as in Example 1, except that the solid electrolyte was prepared by using 100 volume % of LLZO and the firing temperature was set to 1000°C.

[0126] (Comparative Example 2) In addition to using 100% by volume of Li 10.42 Si 1.5 P 1.5 Cl 0.08 O 11.92 A unit cell was manufactured in the same manner as in Example 1, except that a solid electrolyte was prepared and the firing temperature was set to 1000°C.

[0127] (Comparative Example 3) A unit cell was manufactured in the same manner as in Example 1, except that the solid electrolyte was prepared by using 100 vol % of Li 3 BO 3 and the firing temperature was set to 700° C.

[0128] (Comparative Example 4) A unit cell was manufactured in the same manner as in Example 1, except that a composite solid electrolyte was prepared by mixing LLZO and Li 3 BO 3 at a volume ratio of 95:5 and the firing temperature was set to 800° C.

[0129] (Comparative Example 5) A unit cell was manufactured in the same manner as in Comparative Example 4, except that the composite solid electrolyte was prepared by mixing LLZO and Li 3 BO 3 at a volume ratio of 90:10.

[0130] (Comparative Example 6) A unit cell was manufactured in the same manner as in Comparative Example 4, except that the composite solid electrolyte was prepared by mixing LLZO and Li 3 BO 3 at a volume ratio of 85:15.

[0131] (Comparative Example 7) In addition to 10.42 Si 1.5 P 1.5 Cl 0.08 O 11.92 A unit cell was manufactured in the same manner as in Example 1, except that a composite solid electrolyte was prepared by mixing MgSO4 and Li3BO3 at a volume ratio of 85:15.

[0132] (Comparative Example 8) In addition to using 100% by volume of Li 3.2 (V 0.8 Si 0.2 )O4 instead of Li 10.42 Si 1.5 P 1.5 Cl 0.08 O 11.92 A unit cell was manufactured in the same manner as in Comparative Example 2 except that the composite solid electrolyte was prepared.

[0133] (Comparative Example 9) In addition to the use of LLZO, Li 3.2 (V 0.8 Si 0.2 A unit cell was manufactured in the same manner as in Example 1, except that )O4 and Li3BO3 were mixed in a volume ratio of 45:45:10 to prepare a composite solid electrolyte.

[0134] (Comparative Example 10) In addition to the use of LLZO, Li 3.2 (V 0.8 Si 0.2 A unit cell was manufactured in the same manner as in Example 1, except that )O4 and Li3BO3 were mixed in a volume ratio of 75:15:10 to prepare a composite solid electrolyte.

[0135] (Comparative Example 11) In addition to using 100% by volume of Li 10.5 Si 1.5 P 1.5 O 12 Replace Li 10.42 Si 1.5 P 1.5 Cl 0.08 O 11.92 A unit cell was manufactured in the same manner as in Comparative Example 2 except that a solid electrolyte was prepared.

[0136] (Comparative Example 12) In addition to the use of LLZO, Li 10.5 Si 1.5 P 1.5 O 12 A unit cell was manufactured in the same manner as in Example 1, except that a composite solid electrolyte was prepared by mixing Li 3 BO 3 and Li 3 BO 3 at a volume ratio of 45:45:10.

[0137] Table 1 shows the compositions and firing temperatures of Examples 1 to 4 and Comparative Examples 1 to 12 described above.

[0138] [Table 1]

[0139] [Experimental Example] (Experimental Example 1: Measurement of relative density) The unit cells according to Examples 1 to 4 and Comparative Examples 1 to 12 were ion milled or polished to expose each solid electrolyte layer, and the exposed solid electrolyte surface was subjected to X-ray diffraction analysis to calculate true density.

[0140] Then, each solid electrolyte layer exposed in the same manner as described above was sampled into a rectangular plate-shaped piece.

[0141] The mass of the plate-like piece was measured and divided by the calculated apparent volume to obtain the apparent density. The apparent density was divided by the true density to obtain the relative density (%), and these results are shown in Table 2.

[0142] Refer to Table 2, by LLZO, Li 10.42 Si 1.5 P 1.5 Cl 0.08 O 11.92 Examples 1 to 3, in which solid electrolyte layers were prepared by mixing Li 3 BO 3 with Li 3 BO 3 at a specific volume ratio, exhibited high relative densities of 80% or more.

[0143] On the other hand, Comparative Examples 1 to 12 exhibited low relative densities of less than 80%.

[0144] Here, Comparative Example 9 showed a slightly higher relative density, but had a side reaction, which resulted in the overall effect being lower than that of the examples.

[0145] (Experimental Example 2: Measurement of Lithium Ion Conductivity) The lithium ion conductivity of the solid electrolytes of Examples 1 to 4 and Comparative Examples 1 to 12 was measured using the AC impedance method. First, each unit cell was ion milled or polished to expose its solid electrolyte layer, and a portion of the solid electrolyte layer was sampled into a rectangular plate-like piece. Subsequently, electrodes made of gold (Au) were formed at both ends of the obtained piece to prepare the sample. The AC impedance of the sample (frequency: 10 +6 Hz to 10 -1 Hz, voltage: 50 mV to 500 mV), and the results are shown in Table 2.

[0146] "Less than E-08" indicates a case where the measurement result is less than 1.0·E-08 S / cm.

[0147] “Unmeasurable” indicates a case where the lithium ion conductivity of the sample is too low to be electrochemically analyzed.

[0148] Referring to Table 2, the Examples exhibited higher lithium ion conductivity than the Comparative Examples.

[0149] Comparative Examples 8 and 9 exhibit slightly higher lithium ion conductivity, but have side reactions, resulting in overall effects lower than those of the Examples.

[0150] (Experimental Example 3: Side reaction occurs) Since the side reaction is an oxidation-reduction reaction of an element included in the solid electrolyte (for example, V (vanadium) in Comparative Examples 8 and 9), the all-solid-state battery may not function properly when the side reaction occurs. Whether this side reaction occurs is checked by electrochemical analysis, which is cyclic voltammetry (CV) analysis. Since this analysis is a method of recording whether a current is generated within the voltage range in which the analysis is performed, the generation of a current within a specific voltage range confirms that the electrochemical reaction is occurring within the corresponding voltage range. For example, when a peak appears in the + direction or - direction on the y-axis of the graph, it is confirmed that the electrochemical reaction is occurring within the corresponding voltage range. Here, the graph decreases in the range of 0.0V to 0.5V, which is caused by the Li metal interface but is not considered to be a side reaction.

[0151] The analysis was performed in the range of 0.0V to 6.0V, compared with Li metal (vs. Li / Li+), and the results are given in Table 2 as "No", "Yes", or "Unmeasurable". "Unmeasurable" indicates that the lithium ion conductivity of the sample is too low to be electrochemically analyzed. In addition, the side reaction analysis results of Examples 1 and 2 and Comparative Examples 9 and 10 are shown in the form of a graph. Figure 4 middle.

[0152] Referring to Table 2, Examples 1 to 4 had no side reaction, but Comparative Examples 8 to 10 including the LISICON-type solid electrolyte containing V (vanadium) had a side reaction.

[0153] Reference Figure 4 , Examples 1 and 2 exhibited no side reactions between 0.75 and 1.5 V (the range in which side reactions occur), but Comparative Examples 9 and 10 exhibited side reactions within the corresponding range. Compared to Comparative Example 9, Comparative Example 10 exhibited a smaller current peak within the range in which side reactions occur. This is because Comparative Example 10 included a smaller volume % of the LISICON-type solid electrolyte than Comparative Example 9. Side reactions can exhibit different current peak values ​​depending on the volume ratio of each solid electrolyte in the composite solid electrolyte, but no matter how small the side reactions are, the all-solid-state battery may not function properly within the corresponding voltage range.

[0154] [Table 2]

[0155] While the present invention has been described in conjunction with what are presently considered to be practical example embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

[0156] Industrial Applicability The present disclosure relates to a composite solid electrolyte and an all-solid-state battery including the composite solid electrolyte. The composite solid electrolyte can reduce the firing temperature, does not cause side reactions within an operating voltage range of 0 to 6 V, has a high relative density, and has high lithium ion conductivity, and can therefore be used in various electrochemical devices and electronic devices.

[0157] <Description of Reference Signs> 100: All-solid-state battery 112, 114: External electrodes 120: positive electrode layer 121, 122: Positive electrode active material layer 123: Positive electrode current collector 130: Solid electrolyte layer 140: Negative electrode layer 141, 142: Negative electrode active material layer 143: Negative electrode current collector 150: Edge layer.

Claims

1. A composite solid electrolyte, comprising: A garnet-type solid electrolyte; and A Li superionic conductor-type solid electrolyte containing Cl element.

2. The composite solid electrolyte according to claim 1, wherein The Li superionic conductor-type solid electrolyte is represented by Chemical Formula 1: [Chemical Formula 1] Li a M b P c Cl d O e wherein, M includes Zn, Al, Ga, Si, Ge, Ti, Mg or a combination thereof, and a, b, c, d and e are molar ratios of each component, and satisfy 5 ≤ a ≤ 12, 0 < b ≤ 3, 0 < c ≤ 3, 0 < d ≤ 0.1 and 10 ≤ e ≤ 12.

3. The composite solid electrolyte according to claim 2, wherein M includes Si (silicon) or Ge (germanium).

4. The composite solid electrolyte according to claim 2, wherein M does not include V (vanadium).

5. The composite solid electrolyte according to claim 1, the composite solid electrolyte further includes an oxide containing Li element and B element.

6. The composite solid electrolyte according to claim 5, wherein Based on the total volume of the composite solid electrolyte, the oxide containing Li element and B element is included in an amount of 5 vol% to 20 vol%.

7. The composite solid electrolyte according to claim 5, wherein The ratio of the sum of the volume of the garnet-type solid electrolyte and the volume of the Li superionic conductor-type solid electrolyte to the volume of the oxide containing Li element and B element is 80:20 to 90:

10.

8. The composite solid electrolyte according to claim 5, wherein The oxide containing Li element and B element includes Li3BO3, Li4B2O5, LiBO2 or a combination thereof.

9. The composite solid electrolyte according to claim 1, wherein Based on the total volume of the composite solid electrolyte, the garnet-type solid electrolyte is included in an amount of 10 vol% to 50 vol%.

10. The composite solid electrolyte according to claim 1, wherein Based on the total volume of the composite solid electrolyte, the Li superionic conductor-type solid electrolyte is included in an amount of 40 vol% to 80 vol%.

11. The composite solid electrolyte according to claim 1, wherein The ratio of the volume of the garnet-type solid electrolyte to the volume of the Li superionic conductor-type solid electrolyte is 10:80 to 45:

45.

12. The composite solid electrolyte according to claim 1, wherein The ratio of the volume of the garnet-type solid electrolyte to the volume of the Li superionic conductor-type solid electrolyte is 10:80 to 75:

15.

13. The composite solid electrolyte according to claim 1, wherein The composite solid electrolyte has a relative density (%) of greater than or equal to 80%.

14. The composite solid electrolyte according to claim 1, wherein The composite solid electrolyte has a value greater than or equal to 1×10 -7 Lithium ion conductivity (S / cm) at room temperature of 25°C.

15. The composite solid electrolyte according to claim 2, wherein Li a M b P c Cl d ON e including Li 10.42 Yes 1.5 P 1.5 Cl 0.08 ON 11.92 。 16. A all-solid-state battery, comprising: A solid electrolyte layer; And A positive electrode layer and a negative electrode layer, the solid electrolyte layer is disposed between the positive electrode layer and the negative electrode layer, Among them, the solid electrolyte layer includes a composite solid electrolyte. The composite solid electrolyte includes a garnet (LLZO) type solid electrolyte and a Li superionic conductor type solid electrolyte containing Cl element.

17. The all-solid-state battery according to claim 16, wherein The Li superionic conductor type solid electrolyte is represented by Chemical Formula 1: [Chemical Formula 1] Li a M b P c Cl d O e Among them, M includes Zn, Al, Ga, Si, Ge, Ti, Mg or a combination thereof, and a, b, c, d, and e are the molar ratios of each component, and satisfy 5 ≤ a ≤ 12, 0 < b ≤ 3, 0 < c ≤ 3, 0 < d ≤ 0.1, and 10 ≤ e ≤ 12.

18. The all-solid-state battery according to claim 16, the all-solid-state battery further includes an oxide containing Li element and B element.

19. The all-solid-state battery according to claim 17, wherein Li a M b P c Cl d ON e including Li 10.42 Yes 1.5 P 1.5 Cl 0.08 ON 11.92 。 20. An all-solid-state battery, comprising: A stack including a plurality of solid electrolyte layers, a plurality of positive electrode layers, and a plurality of negative electrode layers, the positive electrode layers and the negative electrode layers are alternately arranged, and the plurality of solid electrolyte layers are disposed therebetween; And A first external electrode and a second external electrode are respectively disposed on one surface of the stack and another surface opposite to the one surface, and are respectively connected to the positive electrode layer and the negative electrode layer. Among them, the solid electrolyte layer includes a composite solid electrolyte, and The composite solid electrolyte includes a garnet (LLZO) type solid electrolyte and a Li superionic conductor type solid electrolyte containing Cl element.

21. The all-solid-state battery according to claim 20, wherein The Li superionic conductor type solid electrolyte is represented by Chemical Formula 1: [Chemical Formula 1] Li a M b P c Cl d O e Among them, M includes Zn, Al, Ga, Si, Ge, Ti, Mg or a combination thereof, and a, b, c, d, and e are the molar ratios of each component, and satisfy 5 ≤ a ≤ 12, 0 < b ≤ 3, 0 < c ≤ 3, 0 < d ≤ 0.1, and 10 ≤ e ≤ 12.

22. The all-solid-state battery according to claim 20, the all-solid-state battery further includes an oxide containing Li element and B element.

23. The all-solid-state battery according to claim 21, wherein Li a M b P c Cl d ON e including Li 10.42 Yes 1.5 P 1.5 Cl 0.08 ON 11.92 。

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