Electrode, method for manufacturing the same, and negative electrode-less all-solid-state battery including the same

Abstract

To provide an electrode- and negative electrode-less all-solid-state battery that can operate stably without short circuits even at room temperature. Furthermore, to provide an electrode- and negative electrode-less all-solid-state battery that has a volume expansion mitigation effect and excellent durability characteristics. [Solution] The present invention provides a negative electrode-less all-solid-state battery comprising a current collector and an intermediate layer disposed on the current collector, wherein the intermediate layer comprises a matrix containing a carbon material, a lithium-alloyable metallic element, a lithium-alloyable metallomate element or a combination thereof dispersed in the matrix, and a lithium-alloyable metal oxide, a lithium-alloyable metal fluoride, a lithium-alloyable metallomate oxide, a lithium-alloyable metallomate fluoride or a combination thereof dispersed in the matrix, a method for manufacturing the same, and the electrode.

Description

Technical Field

[0001] The present invention relates to an electrode capable of stable driving without short circuit at room temperature and having excellent durability characteristics, a method for manufacturing the same, and a non-aqueous negative electrode all-solid-state battery including the electrode.

Background Art

[0002] From the viewpoints of battery capacity, stability, output, enlargement, miniaturization, etc., various batteries that can overcome the limitations of lithium secondary batteries are currently being studied. Among these, an all-solid-state battery means a battery that uses a solid instead of an electrolytic solution used in a conventional lithium secondary battery, does not use a flammable solvent in the battery, and there is no risk of ignition or explosion due to decomposition reaction of the conventional electrolytic solution, etc., so the stability can be greatly improved.

[0003] An all-solid-state battery is composed of a laminated structure including a positive electrode and a negative electrode, and a solid electrolyte layer interposed between the positive electrode and the negative electrode. Different from a lithium-ion battery that transfers lithium ions by contact between an electrolytic solution and an active material, an all-solid-state battery transfers lithium by contact between a solid electrolyte and a solid active material. Therefore, in order to optimize the transfer path of lithium ions, it is necessary to maximize the contact between each solid component.

[0004] Recently, research has been conducted on a storage-type anode-less type that removes the negative electrode of an all-solid-state battery and directly deposits lithium on the negative electrode current collector.

Summary of the Invention

Problems to be Solved by the Invention

[0005] An object of the present invention is to provide an electrode and a non-aqueous negative electrode all-solid-state battery that can be stably driven without short circuit even at room temperature by ensuring a sufficient lithium ion diffusion coefficient during charge and discharge of the all-solid-state battery.

[0006] Furthermore, the present invention aims to provide an electrode and a negative electrode-less all-solid-state battery that have a volume expansion mitigation effect and excellent durability characteristics, by inducing uniform electrodeposition of lithium ions at the interface of the intermediate layer.

[0007] The objectives of the present invention are not limited to those mentioned above. The objectives of the present invention will become clearer in the following description and will be achieved by the means and combinations described in the claims. [Means for solving the problem]

[0008] To solve the above problems, the present invention provides an electrode, a method for manufacturing the same, and a negative electrode-less all-solid-state battery including the same.

[0009] (1) The present invention provides an electrode comprising a current collector and an intermediate layer disposed on the current collector, wherein the intermediate layer comprises a matrix containing a carbon material, a lithium-alloyable metallic element, a lithium-alloyable metalloid element or a combination thereof dispersed in the matrix, and a lithium-alloyable metal oxide, a lithium-alloyable metal fluoride, a lithium-alloyable metalloid oxide, a lithium-alloyable metalloid fluoride or a combination thereof dispersed in the matrix.

[0010] (2) In the present invention, the carbon material in (1) above is carbon black, acetylene black, Ketjen black, panel black, furnace black, lamp black, thermal black, natural graphite, artificial graphite, graphene, fullerene (C 60 The present invention provides electrodes that are one or more selected from the group consisting of single-wall carbon nanotubes, multi-wall carbon nanotubes, vapor-grown carbon fibers, carbon felt, and carbon paper.

[0011] (3) The present invention provides an electrode in which the carbon material, in (1) or (2) above, includes amorphous carbon.

[0012] (4) The present invention provides an electrode in which, in any one of (1) to (3) above, the lithium-alloyable metallic element, lithium-alloyable metalloid element, or combination thereof is one or more selected from the group consisting of Ag, Mg, Zn, Au, Sn, Ge, In, Si, Ga, Al, Sb, Pb, Bi, and Cd.

[0013] (5) The present invention provides an electrode in which, in any one of (1) to (4) above, the lithium-alloyable metal oxide, lithium-alloyable metal fluoride, lithium-alloyable metallomate oxide, lithium-alloyable metallomate fluoride, or combination thereof is an oxide or fluoride in which one or more metal elements or metallomate elements selected from the group consisting of Ag, Mg, Zn, Au, Sn, Ge, In, Si, Ga, Al, Sb, Pb, Bi, and Cd can be stoichiometrically composed.

[0014] (6) The present invention provides an electrode in any one of (1) to (5) above, wherein the carbon material has an average particle size greater than the average particle size of particles contained in a lithium alloyable metal element, a lithium alloyable metalloid element, or a combination thereof, and a lithium alloyable metal oxide, metal fluoride, metalloid oxide, metalloid fluoride, or a combination thereof.

[0015] (7) The present invention provides an electrode in which, in any one of (1) to (6) above, the carbon material comprises a carbon material having an average particle size of 1 nm or more and 100 μm or less.

[0016] (8) The present invention provides an electrode in which, in any one of (1) to (7) above, the average particle size of the particles contained in the lithium-alloyable metallic element, lithium-alloyable metalloid element, or combination thereof is 1 nm or more and 100 μm or less.

[0017] (9) The present invention provides an electrode in which, in any one of (1) to (8) above, the average particle size of the particles contained in the lithium-alloyable metal oxide, lithium-alloyable metal fluoride, lithium-alloyable metallomate oxide, lithium-alloyable metallomate fluoride, or a combination thereof is 1 nm or more and 100 μm or less.

[0018] (10) The present invention provides an electrode in which, in any one of (1) to (9) above, the intermediate layer contains the metal element, metalloid element or a combination thereof and the metal oxide, metal fluoride, metalloid oxide, metalloid fluoride or a combination thereof in a content of more than 0% by weight and 50% by weight or less.

[0019] (11) The present invention provides an electrode in which, in any one of (1) to (10) above, the intermediate layer contains the metal element, metalloid element or a combination thereof and the metal oxide, metal fluoride, metalloid oxide, metalloid fluoride or a combination thereof in a weight ratio of 1:0.1 to 9.

[0020] (12) The present invention provides an electrode in any one of (1) to (11) above, wherein the intermediate layer comprises a matrix containing amorphous carbon, Ag dispersed in the matrix, and ZnO dispersed in the matrix.

[0021] (13) In the present invention, in (12) above, the intermediate layer is Li2O dispersed in the matrix and Li2O dispersed in the matrix x The present invention provides an electrode further comprising Zn (where x is 0 ≤ x ≤ 1).

[0022] (14) The present invention provides an electrode in any one of (1) to (13) above, wherein the electrode has a thickness of 1 μm or more and 100 μm or less.

[0023] (15) The present invention includes a current collector and an intermediate layer disposed on the current collector, The aforementioned intermediate layer provides an electrode comprising a matrix containing a carbon material, a lithium-alloyable metallic element, a lithium-alloyable metalloid element, or a combination thereof dispersed in the matrix, and Li2O dispersed in the matrix.

[0024] (16) The present invention provides a method for manufacturing an electrode comprising the steps of: mixing a carbon material, an inorganic element, an inorganic compound, a binder and a solvent to produce a slurry; applying the slurry to at least one surface of a current collector; and drying, wherein the inorganic element includes a lithium-alloyable metallic element, a lithium-alloyable metalloid element or a combination thereof, and the inorganic compound includes a lithium-alloyable metal oxide, a lithium-alloyable metal fluoride, a lithium-alloyable metalloid oxide, a lithium-alloyable metalloid fluoride or a combination thereof.

[0025] (17) The present invention provides a negative electrode-less all-solid-state battery comprising a positive electrode, a negative electrode, and a solid electrolyte layer disposed between the positive electrode and the negative electrode, wherein the positive electrode comprises a positive electrode active material layer containing a positive electrode active material, the negative electrode is an electrode made of any one of (1) to (15), and the solid electrolyte layer is disposed between the positive electrode active material layer and the intermediate layer.

[0026] (18) The present invention provides a negative electrode-less all-solid-state battery in which the positive electrode active material comprises a lithium transition metal composite oxide, as described in (17).

[0027] (19) The present invention provides a negative electrode-less all-solid-state battery in which the solid electrolyte layer comprises a sulfide-based solid electrolyte, as described in (17) or (18).

[0028] (20) The present invention provides a negative electrode-less all-solid-state battery in which the sulfide-based solid electrolyte comprises an argyrodite-type sulfide-based solid electrolyte as described in (19).

[0029] (21) The present invention provides a negative electrode-less all-solid-state battery in which, when charged 100 times or more, one or more elements selected from the group consisting of lithium and Ag are deposited between the intermediate layer and the current collector.

[0030] (22) The present invention provides a negative electrode-less all-solid-state battery in which, according to any one of (17) to (21), the thickness of the negative electrode is 5 μm or more and 100 μm or less when charged 100 times or more. [Effects of the Invention]

[0031] According to the present invention, a negative electrode-less all-solid-state battery can be obtained that can operate stably without short circuits even at room temperature during charging and discharging.

[0032] Furthermore, uniform electrodeposition of lithium ions is induced at the interface of the intermediate layer, resulting in a negative electrode-less all-solid-state battery that has a volume expansion mitigation effect and excellent durability characteristics. [Brief explanation of the drawing]

[0033] [Figure 1] This is a diagram illustrating the electrode according to the present invention. [Figure 2] This is a diagram illustrating a negative electrode-less all-solid-state battery according to the present invention. [Figure 3a] This graph shows the capacity retention rate of the negative electrode-less all-solid-state battery of Example 1 through charge-discharge cycles. [Figure 3b] This graph shows the capacity retention rate of the negative electrode-less all-solid-state battery of Comparative Example 1 through charge-discharge cycles. [Figure 3c] This graph shows the capacity retention rate of the negative electrode-less all-solid-state battery of Comparative Example 2 through charge-discharge cycles. [Figure 4a] This graph shows the analysis of the surface components of the carbon region contained in the negative electrode-less all-solid-state battery of Example 1, obtained by XPS measurement before operation. [Figure 4b]This graph shows the analysis of the surface components of the carbon region contained in the negative electrode-less all-solid-state battery of Example 1, obtained by XPS measurement before operation. [Figure 4c] This graph shows the analysis of the surface components of the carbon region contained in the negative electrode-less all-solid-state battery of Example 1, obtained by XPS measurement before operation. [Figure 4d] This graph shows the analysis of the surface components of the carbon region in the negative electrode-less all-solid-state battery of Example 1, performed by XPS measurement, in the initial charged state. [Figure 4e] This graph shows the analysis of the surface components of the carbon region in the negative electrode-less all-solid-state battery of Example 1, performed by XPS measurement, in the initial charged state. [Figure 4f] This graph shows the analysis of the surface components of the carbon region in the negative electrode-less all-solid-state battery of Example 1, performed by XPS measurement, in the initial charged state. [Figure 4g] This graph shows the analysis of the surface components of the carbon region in the discharged state of the negative electrode-less all-solid-state battery of Example 1, as determined by XPS measurement. [Figure 4h] This graph shows the analysis of the surface components of the carbon region in the discharged state of the negative electrode-less all-solid-state battery of Example 1, as determined by XPS measurement. [Figure 4i] This graph shows the analysis of the surface components of the carbon region in the discharged state of the negative electrode-less all-solid-state battery of Example 1, as determined by XPS measurement. [Figure 5a] This graph shows the changes in current and voltage values ​​when current is applied during the measurement of the lithium-ion diffusion coefficient using the galvanostatic intermittent titration technique (GITT). [Figure 5b] This graph shows the voltage values ​​over time when current is applied to the electrodes of Manufacturing Example 1 and Comparative Manufacturing Example 2. [Figure 5c] This graph shows the value of the lithium ion diffusion coefficient DLi as a voltage is applied to the electrode in Manufacturing Example 1. [Figure 5d] This graph shows the value of the lithium ion diffusion coefficient DLi as a voltage is applied to the electrode in comparative manufacturing example 2. [Figure 6a] This graph shows the voltage and current as the scanning speed of the electrode in manufacturing example 1 increases. [Figure 6b] This graph shows the current density as the scanning speed of the electrode in manufacturing example 1 increases. [Figure 6c] This graph shows the current density as the scanning speed of the electrode in manufacturing example 1 increases. [Figure 6d] This graph shows the voltage and current as the scanning speed of the electrodes in comparative manufacturing example 2. [Figure 6e] This graph shows the current density of the electrodes in comparative manufacturing example 2 as they change based on their scanning speed. [Figure 6f] This graph shows the current density of the electrodes in comparative manufacturing example 2 as they change based on their scanning speed. [Figure 7a] This graph shows the voltage values ​​over time when current is applied to the negative electrode-less all-solid-state battery of Example 1 and the negative electrode-less all-solid-state battery of Comparative Example 2. [Figure 7b] This graph shows the voltage-dependent relaxation voltage values ​​of the negative electrode-less all-solid-state battery of Example 1 and the negative electrode-less all-solid-state battery of Comparative Example 2. [Figure 8a] This is a SEM image of the initial state of the negative electrode-less all-solid-state battery of Example 1. [Figure 8b] This is a SEM image of a cross-section of the negative electrode-less all-solid-state battery of Example 1 in a fully charged state. [Figure 9a] This graph shows the rate-limiting characteristics of the negative electrode-less all-solid-state batteries manufactured in Examples 1 and 2 of the present invention, based on their charge and discharge rates. [Figure 9b] This graph shows the rate-limiting characteristics of the negative electrode-less all-solid-state batteries manufactured in Examples 1 and 3 of the present invention, based on their charge and discharge rates. [Figure 9c] This graph shows the rate-limiting characteristics of the negative electrode-less all-solid-state batteries manufactured in Examples 1 and 4 of the present invention, based on their charge and discharge rates. [Figure 9d]This graph shows the rate-limiting characteristics of the charge-discharge rate of the negative electrode-less all-solid-state batteries manufactured in Examples 1 and 5 of the present invention. [Modes for carrying out the invention]

[0034] The present invention will be described in more detail below to facilitate understanding of it.

[0035] The terms and words used herein and in the claims should not be interpreted in a manner limited to their ordinary or dictionary meanings, but rather in a manner consistent with the technical idea of ​​the present invention, in accordance with the principle that inventors may define the concepts of terms as appropriate to best describe their invention.

[0036] The terms used herein are for illustrative purposes only and are not intended to limit the invention. Singular expressions include plural expressions unless the context clearly indicates otherwise.

[0037] In this specification, terms such as “includes,” “equip,” or “have” indicate the presence of implemented features, figures, steps, components, or combinations thereof, but should be understood not to preclude the existence or possibility of adding one or more different features, figures, steps, components, or combinations thereof.

[0038] Hereinafter, embodiments of the present invention will be described in detail so that they can be easily implemented by a person with ordinary skill in the art to which the present invention pertains. However, the present invention can be realized in a variety of different forms and is not limited to the embodiments described herein.

[0039] electrode The present invention provides an electrode 10 comprising a current collector 11 and an intermediate layer 12 disposed on the current collector 11, wherein the intermediate layer 12 comprises a matrix containing a carbon material, a lithium-alloyable metallic element, a lithium-alloyable metalloid element, or a combination thereof dispersed in the matrix, and a lithium-alloyable metal oxide, a lithium-alloyable metal fluoride, a lithium-alloyable metalloid oxide, a lithium-alloyable metalloid fluoride, or a combination thereof dispersed in the matrix.

[0040] Furthermore, the present invention provides an electrode 10 comprising a current collector 11 and an intermediate layer 12 disposed on the current collector 11, wherein the intermediate layer 12 comprises a matrix containing a carbon material, and an electrode 10 comprising a lithium-alloyable metallic element, a lithium-alloyable metalloid element, or a combination thereof dispersed in the matrix, and Li2O dispersed in the matrix.

[0041] Figure 1 is a diagram illustrating the electrode 10 according to the present invention. Referring to this, the electrode 10 may have a current collector 11 and an intermediate layer 12 stacked on top of each other, but is not limited to this, and other components may be further stacked.

[0042] The electrode 10 may also be a negative electrode.

[0043] The electrode 10 may have a thickness of 1 μm or more, 3 μm or more, 5 μm or more, 7 μm or more, 9 μm or more, 11 μm or more, 13 μm or more, or 15 μm or more, and may also be 100 μm or less, 90 μm or less, 80 μm or less, 70 μm or less, 60 μm or less, 50 μm or less, 40 μm or less, or 30 μm or less.

[0044] According to one embodiment of the present invention, the current collector 11 plays a role in collecting current so that electrons can move to the external circuit of the battery, and provides high electrical conductivity to enable electrons to move rapidly. The current collector 11 can also play the role of a negative electrode current collector inside a negative electrode-less all-solid-state battery.

[0045] The current collector 11 may be a plate-shaped substrate with electrical conductivity. Specifically, the current collector 11 may be in the form of a sheet, a thin film, or a foil. Furthermore, the type of current collector 11 may include materials that do not cause chemical changes in the battery and are conductive, and specifically, it may include one or more selected from the group consisting of copper, stainless steel, aluminum, nickel, titanium, calcined carbon, copper or stainless steel with surface treatment with carbon, nickel, titanium, silver, etc., and aluminum-cadmium alloys.

[0046] According to one embodiment of the present invention, the thickness of the current collector 11 may be 1 μm or more, 2 μm or more, 3 μm or more, 4 μm or more, 5 μm or more, 50 μm or less, 40 μm or less, 30 μm or less, 20 μm or less, or 10 μm or less.

[0047] According to one embodiment of the present invention, the intermediate layer 12 can maintain interfacial contact with the solid electrolyte layer 20 during charging and discharging of the negative electrode-less all-solid-state battery, act as an interfacial protective film, and also act as a pathway for lithium ions flowing in from the positive electrode active material layer to pass through.

[0048] The intermediate layer 12 can be placed on the current collector 11. The intermediate layer 12 may also include a matrix containing a carbon material, a lithium-alloyable metallic element, a lithium-alloyable metalloid element, or a combination thereof dispersed in the matrix, and a lithium-alloyable metal oxide, a lithium-alloyable metal fluoride, a lithium-alloyable metalloid oxide, a lithium-alloyable metalloid fluoride, or a combination thereof dispersed in the matrix, and the intermediate layer 12 may contain Li2O and Li2O dispersed in the matrix. x It can further include Zn (where x is 0 ≤ x ≤ 1).

[0049] Hollow spaces exist between the carbon materials contained in the matrix, and relatively small particle sizes can be dispersed and arranged inside these hollow spaces. Furthermore, during charging of the negative electrode-less all-solid-state battery, lithium ions can bond with the carbon atoms contained in the matrix, allowing lithium to be electrodeposited onto the matrix. In addition, the carbon materials contained in the matrix can include materials containing carbon elements, specifically carbon black, acetylene black, Ketjen black, panel black, furnace black, lamp black, thermal black, natural graphite, artificial graphite, graphene, and fullerene (C). 60 The matrix may contain one or more selected from the group consisting of single-wall carbon nanotubes, multi-wall carbon nanotubes, vapor-grown carbon fibers, carbon felt, and carbon paper, and preferably acetylene black. The carbon material may also contain amorphous carbon. When the carbon material contained in the matrix contains amorphous carbon, it acts as an interfacial protective film that prevents direct contact between the electrodeposited lithium and the solid electrolyte during charging and discharging, enabling stable operation without short circuits (short-circuit phenomena) even at room temperature, and improving durability.

[0050] The metallic elements, metalloid elements, or combinations thereof dispersed in the matrix may be alloyable with lithium, and as a specific example, they may be one or more selected from the group consisting of Ag, Mg, Zn, Au, Sn, Ge, In, Si, Ga, Al, Sb, Pb, Bi, and Cd, and as a more specific example, Ag. If the metallic elements, metalloid elements, or combinations thereof are alloyable with lithium, the metallic element or metalloid element may be alloyed with Li and lithium-metal alloy (M x Li(Li) can be formed and remain in the carbon matrix voids, inducing the uniform formation of a lithium deposition layer between the intermediate layer and the current collector.

[0051] The metal oxide, metal fluoride, metalloid oxide, metalloid fluoride, or combination thereof dispersed in the matrix may be alloyable with lithium. Specific examples include oxides or fluorides stoichiometrically composed of one or more metal or metalloid elements selected from the group consisting of Ag, Mg, Zn, Au, Sn, Ge, In, Si, Ga, Al, Sb, Pb, B, and Cd. A more specific example is ZnO. When the intermediate layer contains the metal oxide, metal fluoride, metalloid oxide, metalloid fluoride, or combination thereof, it provides a migration pathway for lithium ions and can guide lithium ions to uniformly electrodeposit into the voids within the matrix.

[0052] The Li2O dispersed in the matrix may be formed when lithium ions react with metal oxides, metal fluorides, metalloid oxides, or metalloid fluorides during charging. x Zn (where x is 0 ≤ x ≤ 1) may be formed by the reaction of Zn and lithium.

[0053] The matrix can contain, in a dispersed manner, lithium-alloyable metallic elements, lithium-alloyable metalloid elements, or combinations thereof, lithium-alloyable metallic oxides, lithium-alloyable metallic fluorides, lithium-alloyable metalloid oxides, lithium-alloyable metalloid fluorides, or combinations thereof. When arranged as described above, during charging, they react with lithium ions flowing in from the positive electrode active material layer to form a lithium-metal alloy (M x Li) and lithium oxide (Li2O) are formed, and during discharge, a reverse reaction forms metal elements and lithium ions. This electrochemical reaction facilitates the diffusion of lithium ions within the electrode during charging and discharging, inducing uniform electrodeposition / deposition of lithium ions in the voids within the matrix.

[0054] The carbon material may have an average particle size greater than that of particles contained in metallic elements, metalloid elements, or combinations thereof, and particles contained in metal oxides, metal fluorides, metalloid oxides, metalloid fluorides, or combinations thereof. Due to the difference in average particle size, particles contained in metallic elements, metalloid elements, or combinations thereof, and particles contained in metal oxides, metal fluorides, metalloid oxides, metalloid fluorides, or combinations thereof, which have relatively small average particle sizes, can be uniformly distributed in the hollow spaces between the carbon materials. These particles react with lithium ions in the hollow spaces between the carbon materials, and the lithium alloy formation reaction proceeds reversibly in order according to the reactivity. As a result, even at room temperature, lithium ions have excellent lithium diffusion kinetics, and even as the charge-discharge cycle progresses, lithium ions are uniformly electrodeposited / deposited without the occurrence of short circuits, and durability characteristics can also be improved.

[0055] The carbon material may include carbon materials with an average particle size of 1 nm or more, 3 nm or more, 5 nm or more, 7 nm or more, 9 nm or more, 11 nm or more, 13 nm or more, 15 nm or more, 17 nm or more, 19 nm or more, 21 nm or more, 23 nm or more, 25 nm or more, 27 nm or more, 29 nm or more, 31 nm or more, 33 nm or more, and 35 nm or more, and may include carbon materials with an average particle size of 100 μm or less, 90 μm or less, 80 μm or less, 70 μm or less, 60 μm or less, 50 μm or less, 40 μm or less, 30 μm or less, 20 μm or less, 10 μm or less, 5 μm or less, 2 μm or less, 1 μm or less, 800 nm or less, 600 nm or less, 400 nm or less, 200 nm or less, 100 nm or less, 90 nm or less, 80 nm or less, 70 nm or less, 60 nm or less, and 50 nm or less. If the above range is met, the discharge capacity and output characteristics can be further improved.

[0056] The metallic elements alloyable with lithium, the metalloid elements alloyable with lithium, or combinations thereof may have an average particle size of 1 nm or more, 2 nm or more, 4 nm or more, 6 nm or more, 8 nm or more, 10 nm or more, 12 nm or more, 14 nm or more, 16 nm or more, 18 nm or more, 20 nm or more, 22 nm or more, 24 nm or more, 26 nm or more, 28 nm or more, 30 nm or more, and may be 100 μm or less, 90 μm or less, 80 The wavelength may be less than or equal to μm, 70 μm or less, 60 μm or less, 50 μm or less, 40 μm or less, 30 μm or less, 20 μm or less, 10 μm or less, 5 μm or less, 2 μm or less, 1 μm or less, 900 nm or less, 800 nm or less, 700 nm or less, 600 nm or less, 500 nm or less, 400 nm or less, 300 nm or less, 200 nm or less, 100 nm or less, 90 nm or less, 80 nm or less, 70 nm or less, 60 nm or less, or 50 nm or less. If the above ranges are met, the discharge capacity and output characteristics can be further improved.

[0057] The lithium-alloyable metal oxides, lithium-alloyable metal fluorides, lithium-alloyable metallomate oxides, lithium-alloyable metallomate fluorides, or combinations thereof may have an average particle size of 1 nm or more, 2 nm or more, 4 nm or more, 6 nm or more, 8 nm or more, 10 nm or more, 12 nm or more, 14 nm or more, 16 nm or more, 18 nm or more, 20 nm or more, 22 nm or more, 24 nm or more, 26 nm or more, 28 nm or more, or 30 nm or more. The wavelengths may also be 100 μm or less, 90 μm or less, 80 μm or less, 70 μm or less, 60 μm or less, 50 μm or less, 40 μm or less, 30 μm or less, 20 μm or less, 10 μm or less, 5 μm or less, 2 μm or less, 1 μm or less, 900 nm or less, 800 nm or less, 700 nm or less, 600 nm or less, 500 nm or less, 400 nm or less, 300 nm or less, 200 nm or less, 100 nm or less, 90 nm or less, 80 nm or less, 70 nm or less, 60 nm or less, or 50 nm or less. If the above ranges are met, the discharge capacity and output characteristics can be further improved.

[0058] The intermediate layer may contain the metal element, metalloid element or a combination thereof, and the metal oxide, metal fluoride, metalloid oxide, metalloid fluoride, or a combination thereof in a content of more than 0% by weight, 5% or more by weight, 10% or more by weight, 15% or more by weight, 20% or more by weight, or 25% or more by weight, and may contain 50% or less by weight, 45% or less by weight, 40% or less by weight, 35% or less by weight, or 30% or less by weight. When the above content conditions are met, a sufficient amount of the metal element, metalloid element, metal oxide, metal fluoride, metalloid oxide, or metalloid fluoride is distributed in the hollow space between the carbon materials, and the lithium alloy formation reaction can be activated.

[0059] The intermediate layer may contain the metal element, metalloid element or a combination thereof and the metal oxide, metal fluoride, metalloid oxide, metalloid fluoride, or a combination thereof in a weight ratio of 1:0.1 to 9, or in a weight ratio of 1:0.1 to 5. When the weight ratio conditions are met, the metal element, metalloid element or a combination thereof and the metal oxide, metal fluoride, metalloid oxide, metalloid fluoride, or a combination thereof are distributed in appropriate proportions in the hollow space between the carbon materials, and the lithium alloy formation reaction can be activated.

[0060] Electrode manufacturing method The electrode manufacturing method according to the present invention may include the steps of: mixing a carbon material, an inorganic element, an inorganic compound, a binder, and a solvent to produce a slurry (S10); applying the slurry to at least one surface of a current collector (S20); and drying (S30).

[0061] In step (S10), the inorganic element may include a metallic element alloyable with lithium, a metalloid element alloyable with lithium, or a combination thereof, and the inorganic compound may include a metallic oxide alloyable with lithium, a metallic fluoride alloyable with lithium, a metalloid oxide alloyable with lithium, a metalloid fluoride alloyable with lithium, or a combination thereof.

[0062] In step (S10), the carbon material, the lithium-alloyable metallic element contained in the inorganic element, the lithium-alloyable metalloid element or combination thereof, and the lithium-alloyable metal oxide, lithium-alloyable metal fluoride, lithium-alloyable metalloid oxide, lithium-alloyable metalloid fluoride or combination thereof contained in the inorganic compound are applicable as described above.

[0063] The binder may be a polymer binder that does not react with inorganic elements and inorganic compounds. For example, the binder may include polyvinylidene fluoride (PVDF), carboxymethyl cellulose (CMC), polyethylene oxide (PEO), polymethyl methacrylate (PMMA), polytetrafluoroethylene (PTFE), and the like.

[0064] Any solvent can be used as long as it can dissolve the carbon material, the inorganic element, the inorganic compound, and the binder. For example, the solvent may include water, acetone, ethanol, N-methylpyrrolidone (NMP), dimethyl sulfoxide (DMSO), tetrahydrofuran (THF), and the like.

[0065] During the production of the slurry, the carbon material, inorganic elements, lithium-alloyable metal oxides, lithium-alloyable metal fluorides, lithium-alloyable metal oxides, lithium-alloyable metal fluorides, or combinations thereof, binder, and solvent contained in the slurry described in step (S10) can be added simultaneously or at different times.

[0066] In step (S20), the slurry may be applied to at least one surface of the current collector, or to both surfaces of the current collector. Exemplarily, the application can be carried out by any one method selected from the group consisting of doctor blade, die casting, comma coating, screen printing, spray spraying, electrospinning, roll coating, and brushing.

[0067] In step (S30), the drying process may be a step of drying the coated layer to evaporate the solvent and form an intermediate layer, and can be carried out by methods such as air drying, oven drying, vacuum drying, or microwave drying. Furthermore, the drying can be carried out in a temperature range of 70°C or higher, 75°C or higher, 80°C or higher, 85°C or higher, 90°C or higher, 95°C or higher, or 100°C or lower, or in a temperature range of 150°C or lower, 145°C or lower, 140°C or lower, 135°C or lower, 130°C or lower, 125°C or lower, or 120°C or lower. When the temperature range of the drying process satisfies the above range, uniform drying can be achieved, residual solvent can be minimized, electrochemical instability can be reduced, and an intermediate layer of uniform thickness can be obtained.

[0068] Anode-less all-solid-state battery The negative electrode-less all-solid-state battery according to the present invention may include a positive electrode 30, a negative electrode, and a solid electrolyte layer 20 disposed between the positive electrode 30 and the negative electrode. As a specific example, the negative electrode-less all-solid-state battery may include a unit cell. The negative electrode-less all-solid-state battery may mean the unit cell itself, or it may mean a negative electrode-less all-solid-state battery formed by stacking a plurality of unit cells. The unit cell may have a negative electrode, a solid electrolyte layer, and a positive electrode stacked in that order. As a specific example, as shown in Figure 2, the negative electrode, the solid electrolyte layer 20, and the positive electrode 30 may be stacked in that order, and the negative electrode may be the electrode 10 described above.

[0069] The aforementioned negative electrode-less all-solid-state battery may, after being charged 100 or more times, have one or more elements selected from the group consisting of lithium and Ag deposited between the intermediate layer 12 and the current collector 11. Specifically, during charging, the negative electrode-less all-solid-state battery may have lithium ions reacting with metal oxides, metal fluorides, metalloid oxides, metalloid fluorides, or combinations thereof to form a lithium-metal alloy (M x This induces the formation of Li) and lithium oxide (Li2O), where lithium ions can be deposited between the intermediate layer and the current collector. As charging and discharging progresses, some of the Ag dispersed in the matrix of the intermediate layer 12 migrates to the lithium deposition layer and can exist between the intermediate layer 12 and the current collector 11.

[0070] The negative electrode-less all-solid-state battery may have a negative electrode thickness of 5 μm or more, 7 μm or more, 9 μm or more, 11 μm or more, 13 μm or more, 15 μm or more, 17 μm or more, or 19 μm or more when charged 100 times or more, and may also have a negative electrode thickness of 100 μm or less, 90 μm or less, 80 μm or less, 70 μm or less, 60 μm or less, 50 μm or less, 40 μm or less, or 30 μm or less.

[0071] The negative electrode in one embodiment of the present invention may be the electrode 10 described above.

[0072] The solid electrolyte layer 20 according to one embodiment of the present invention can serve as a lithium ion transport path and may be placed between the positive electrode active material and the intermediate layer. The solid electrolyte layer 20 may also contain a solid electrolyte and a binder. The solid electrolyte may contain a material having lithium ion conductivity, and more specifically, it may contain at least one selected from the group consisting of oxide-based solid electrolytes, sulfide-based solid electrolytes, polymer electrolytes and combinations thereof, and more specifically, it may contain a sulfide-based solid electrolyte. The sulfide-based solid electrolyte has high lithium ion conductivity and is more preferable as a solid electrolyte.

[0073] The sulfide-based solid electrolyte can include one or more selected from the group consisting of LPS-based solid electrolytes, Thio-LISICON-based solid electrolytes, LGPS-based solid electrolytes, and argyrodite-type sulfide-based solid electrolytes. Specifically, it can include argyrodite-type sulfide-based solid electrolytes. For example, the sulfide-based solid electrolyte can be Li2S-P2S5, Li2S-P2S5-LiI, Li2S-P2S5-LiCl, Li2S-P2S5-LiBr, Li2S-P2S5-Li2O, Li2S-P2S5-Li2O-LiI, Li2S-SiS2, Li2S-SiS2-LiI, Li2S-SiS2-LiBr, Li2S-SiS2-LiCl, Li2S-SiS2-B2S3-LiI, Li2S-SiS2-P2S5-LiI, Li2S-B2S3, Li2S-P2S5-ZmSn (where m and n are positive numbers, and Z is one of Ge, Zn, Ga), Li2S-GeS2, Li2S-SiS2-Li3PO4, Li2S-SiS2-Li x MO y (where x and y are positive numbers, and M is one of P, Si, Ge, B, Al, Ga, In), Li6PS5Cl, Li 5.5 PS 4.5 Cl 1.5 , Li6PS5C l0.5 br 0.5 and Li 10 geP2S 12 and can include one or more selected from the group consisting of, specifically, Li6PS5Cl, Li 5.5 PS 4.5 Cl 1.5 and Li6PS5Cl 0.5 br 0.5 and can include one or more selected from the group consisting of, more specifically, Li6PS5C l0.5 br 0.5 can be included.

[0074] The binder may include butadiene rubber, nitrile butadiene rubber, hydrogenated nitrile butadiene rubber, polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), carboxymethyl cellulose (CMC), and the like.

[0075] A positive electrode 30 according to one embodiment of the present invention may include a positive electrode active material layer containing a positive electrode active material, the positive electrode active material layer may play a role in reversibly intercalating and releasing lithium ions. The positive electrode may also be in a form in which the positive electrode active material is coated onto a current collector, and the positive electrode active material layer may include the positive electrode active material, a solid electrolyte, a conductive material, a binder, etc.

[0076] The positive electrode active material may be one or more selected from the group consisting of lithium-manganese oxide, lithium-cobalt oxide, lithium-nickel oxide, lithium-nickel-manganese oxide, lithium-nickel-cobalt oxide, lithium-manganese-cobalt oxide, and lithium-nickel-cobalt-manganese oxide.

[0077] The positive electrode active material is specifically LiMnO2, LiMn2O, LiCoO2, LiNiO2, LiNi 1-Y Mn Y O2(where 0 <y<1)、LiNi 1-Y Co Y O2(where 0 <y<1)、LiMn 2-z Co z O4 (Here, 0 <z<2)など)、Li(Ni P Co Q Mn R )O2(Here, 0 <P<1、0<Q<1、0<R<1、P+Q+R=1)およびLI(Ni PCo Q Mn R )O4 (where 0 < P < 2, 0 < Q < 2, 0 < R < 2, and P + Q + R = 2) may be one or more selected from the group consisting of. Among them, in terms of enhancing the capacity characteristics and stability of the battery, LiNi 0.6 Mn 0.2 Co 0.2 O2, LiNi 0.5 Mn 0.3 Co 0.2 O2, LiNi 0.7 Mn 0.15 Co 0.15 O2, LiNi 0.8 Mn 0.1 Co 0.1 O2 may be one or more selected from the group consisting of.

[0078] The positive electrode active material can be doped with a transition metal, and the doping element can specifically include one or more selected from the group consisting of Al, Mo, Nb, K, Cl, Na, Ti, Mg, Ru, Ta, Zr, W, Ti, and B. As a specific example, the positive electrode active material can include a lithium transition metal composite oxide represented by the following Chemical Formula 1.

[0079] [Chemical Formula 1] Li x Ni a Mn b Co c M d O2

[0080] In the Chemical Formula 1, M includes one or more selected from the group selected from Al, Mo, Nb, K, Cl, Na, Ti, Mg, Ru, Ta, Zr, W, Ti, and B, 0.9 < x < 1.3, 0 < a < 1, 0 < b < 1, 0 < c < 1, 0 ≤ d < 0.2, but a + b + c + d = 1.

[0081] Specifically, in the chemical formula 1, a may be greater than 0, 0.1 or more, 0.2 or more, 0.3 or more, 0.4 or more, 0.5 or more, 0.6 or more, 0.7 or more, or less than 1, 0.95 or less, 0.9 or less, or 0.85 or less. Also, in the chemical formula 1, b may be greater than 0, 0.01 or more, 0.02 or more, 0.03 or more, 0.04 or more, 0.05 or more, 0.06 or more, 0.07 or more, 0.08 or more, or 0.09 or more, or less than 1, 0.9 or less, 0.8 or less, 0.7 or less, 0.6 or less, 0.5 or less, 0.4 or less, 0.3 or less, or 0.2 or less. Furthermore, in the chemical formula 1, c may be greater than 0, 0.01 or more, 0.02 or more, 0.03 or more, 0.04 or more, 0.05 or more, 0.06 or more, 0.07 or more, 0.08 or more, 0.09 or more, and may be less than 1, 0.9 or less, 0.8 or less, 0.7 or less, 0.6 or less, 0.5 or less, 0.4 or less, 0.3 or less, or 0.2 or less. Furthermore, in the chemical formula 1, d may be greater than 0, 0.01 or more, 0.02 or more, 0.03 or more, 0.04 or more, 0.05 or more, 0.06 or more, 0.07 or more, 0.08 or more, 0.09 or more, and may also be less than 0.2, 0.19 or less, 0.18 or less, 0.17 or less, 0.16 or less, 0.15 or less, 0.14 or less, 0.13 or less, 0.12 or less, or 0.11 or less.

[0082] The positive electrode active material may include a coating formed on its surface. The coating may include a Li-MO solid solution (where M is one or more selected from Al, Mo, Nb, K, Cl, Na, Ti, Mg, Ru, Ta, Zr, W, Ti, and B) on the surface of the positive electrode active material. The Li-MO solid solution may also include one or more selected from Li-Nb-O, Li-Co-O, and Li-Ti-O. Specifically, the Li-MO solid solution may include one or more selected from LiNbO2, LiNbO3, LiCoO2, and Li2TiO3, and more specifically, one or more selected from LiNbO3 and LiCoO2. In this case, the lithium-ion conductivity and electrical conductivity of the coating including the Li-MO solid solution are excellent, and as a result, a lithium secondary battery with low internal resistance can be realized.

[0083] Furthermore, the coating portion may contain a solid electrolyte. The solid electrolyte may contain a substance having lithium ion conductivity, and more specifically, it may contain at least one selected from the group consisting of oxide-based solid electrolytes, sulfide-based solid electrolytes, polymer electrolytes, and combinations thereof, and more specifically, it may contain a sulfide-based solid electrolyte. The solid electrolyte may also contain a sulfide-based solid electrolyte represented by the following chemical formula 2.

[0084] [Chemical formula 2] Li e P f S g X h

[0085] In the above chemical formula 2, X is F, Cl, Br or I, and 0 <e≦10であり、0<f≦10であり、0<g≦15であり、0≦h≦20である。

[0086] Specifically, in the chemical formula 2, e may be greater than 0, 1 or more, 2 or more, 3 or more, 4 or more, 5 or more, or 10 or less, 9 or less, 8 or less, 7 or less, or 6 or less. Also, in the chemical formula 2, f may be greater than 0, 1 or more, 2 or more, 3 or more, 4 or more, 5 or more, or 10 or less, 9 or less, 8 or less, 7 or less, or 6 or less. Also, in the chemical formula 2, g may be greater than 0, 1 or more, 2 or more, 3 or more, 4 or more, 5 or more, 6 or more, or 7 or more, or 15 or less, 14 or less, 13 or less, 12 or less, 11 or less, 10 or less, or 9 or less. Also, in the chemical formula 2, h may be greater than 0, 2 or more, 4 or more, 6 or more, 8 or more, 10 or more, or 20 or less, 18 or less, 16 or less, 14 or less, or 12 or less.

[0087] The conductive material may be carbon black, conductive graphite, ethylene black, graphene, or the like.

[0088] The binder may include butadiene rubber, nitrile butadiene rubber, hydrogenated nitrile butadiene rubber, polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), carboxymethyl cellulose (CMC), and the like.

[0089] The positive electrode current collector may be a plate-shaped substrate with electrical conductivity. Specifically, the positive electrode current collector may be in the form of a sheet or a thin film. The positive electrode current collector may also include at least one selected from the group consisting of indium, copper, magnesium, aluminum, stainless steel, iron, and combinations thereof.

[0090] Other embodiments of the present invention will be described in more detail below with reference to examples. The following examples are merely illustrative to facilitate understanding of the present invention, and the scope of the present invention is not limited thereto.

[0091] Manufacturing Example 1: Manufacturing of an electrode containing an AgZnO / C mixed slurry Acetylene black with an average particle size of 50 nm was prepared as the carbon material. Silver (Ag) nanopowder with an average particle size of 40 nm was prepared as the metal. Zinc oxide (ZnO) with an average particle size of 40 nm was prepared as the metal oxide. The metal and metal oxide were mixed in a 5:5 weight ratio and added at a concentration of 25% by weight, the carbon material was added at a concentration of 75% by weight, and the mixture was produced by dry milling.

[0092] A slurry was prepared by adding 93.7% by weight of the aforementioned mixture and 6.3% by weight of a binder (polyvinylidene fluoride, PVDF) to a solvent (N-methylpyrrolidone, NMP). The slurry was applied to a current collector and dried at 100°C to form an intermediate layer. Nickel foil was used as the current collector.

[0093] Manufacturing Example 2: Preparation of electrodes containing an AgZnO / C mixed slurry Acetylene black with an average particle size of 50 nm was prepared as the carbon material. Silver (Ag) nanopowder with a particle size of 10 nm was prepared as the metal. Zinc oxide (ZnO) with an average particle size of 40 nm was prepared as the metal oxide. The metal and metal oxide were mixed in a 5:5 weight ratio and added at a concentration of 25% by weight, the carbon material was added at a concentration of 75% by weight, and the mixture was produced by dry milling.

[0094] A slurry was prepared by adding 93.7% by weight of the aforementioned mixture and 6.3% by weight of a binder (polyvinylidene fluoride, PVDF) to a solvent (N-methylpyrrolidone, NMP). The slurry was applied to a current collector and dried at 100°C to form an intermediate layer. Nickel foil was used as the current collector.

[0095] Manufacturing Example 3: Manufacturing of electrodes containing an AgZnO / C mixed slurry Acetylene black with an average particle size of 50 nm was prepared as the carbon material. Silver (Ag) nanopowder with an average particle size of 500 nm was prepared as the metal. Zinc oxide (ZnO) with an average particle size of 40 nm was prepared as the metal oxide. The metal and metal oxide were mixed in a 5:5 weight ratio and added at a concentration of 25% by weight, the carbon material was added at a concentration of 75% by weight, and the mixture was produced by dry milling.

[0096] A slurry was prepared by adding 93.7% by weight of the aforementioned mixture and 6.3% by weight of a binder (polyvinylidene fluoride, PVDF) to a solvent (N-methylpyrrolidone, NMP). The slurry was applied to a current collector and dried at 100°C to form an intermediate layer. Nickel foil was used as the current collector.

[0097] Manufacturing Example 4: Preparation of electrodes containing an AgZnO / C mixed slurry Acetylene black with an average particle size of 50 nm was prepared as the carbon material. Silver (Ag) nanopowder with an average particle size of 40 nm was prepared as the metal. Zinc oxide (ZnO) with an average particle size of 20 nm was prepared as the metal oxide. The metal and metal oxide were mixed in a 5:5 weight ratio and added at a concentration of 25% by weight, the carbon material was added at a concentration of 75% by weight, and the mixture was produced by dry milling.

[0098] A slurry was prepared by adding 93.7% by weight of the aforementioned mixture and 6.3% by weight of a binder (polyvinylidene fluoride, PVDF) to a solvent (N-methylpyrrolidone, NMP). The slurry was applied to a current collector and dried at 100°C to form an intermediate layer. Nickel foil was used as the current collector.

[0099] Manufacturing Example 5: Preparation of an electrode containing an AgZnO / C mixed slurry Acetylene black with an average particle size of 50 nm was prepared as the carbon material. Silver (Ag) nanopowder with an average particle size of 40 nm was prepared as the metal. Zinc oxide (ZnO) with an average particle size of 200 nm was prepared as the metal oxide. The metal and metal oxide were mixed in a 5:5 weight ratio and added at a concentration of 25% by weight, the carbon material was added at a concentration of 75% by weight, and the mixture was produced by dry milling.

[0100] A slurry was prepared by adding 93.7% by weight of the aforementioned mixture and 6.3% by weight of a binder (polyvinylidene fluoride, PVDF) to a solvent (N-methylpyrrolidone, NMP). The slurry was applied to a current collector and dried at 100°C to form an intermediate layer. Nickel foil was used as the current collector.

[0101] Comparative manufacturing example 1: Manufacturing of electrodes containing an AgZnO mixed slurry Silver (Ag) nanopowder with an average particle size of 40 nm was prepared as the metal. Zinc oxide (ZnO) with an average particle size of 40 nm was prepared as the metal oxide. The metal and the metal oxide were mixed in a 5:5 weight ratio and added at 100% by weight, and the mixture was produced by dry milling.

[0102] A slurry was prepared by adding 93.7% by weight of the aforementioned mixture and 6.3% by weight of a binder (polyvinylidene fluoride, PVDF) to a solvent (N-methylpyrrolidone, NMP). The slurry was applied to a current collector and dried at 100°C to form an intermediate layer. Nickel foil was used as the current collector.

[0103] Comparative Manufacturing Example 2 - Manufacturing of an electrode containing an Ag / C mixed slurry Acetylene black with an average particle size of 50 nm was prepared as the carbon material. Silver (Ag) nanopowder with an average particle size of 40 nm was prepared as the metal. 25% by weight of the metal and 75% by weight of the carbon material were placed in separate containers and dry-milled to produce the mixture.

[0104] A slurry was prepared by adding 93.7% by weight of the aforementioned mixture and 6.3% by weight of a binder (polyvinylidene fluoride, PVDF) to a solvent (N-methylpyrrolidone, NMP). The slurry was applied to a current collector and dried at 100°C to form an intermediate layer. Nickel foil was used as the current collector.

[0105] A slurry was prepared by adding 93.7% by weight of the aforementioned mixture and 6.3% by weight of a binder (polyvinylidene fluoride, PVDF) to a solvent (N-methylpyrrolidone, NMP). The slurry was applied to a current collector and dried at 100°C to form an intermediate layer. Nickel foil was used as the current collector.

[0106]

[0107] Example 1 - Manufacturing of a negative electrode-less all-solid-state battery including the electrodes of Manufacturing Example 1 The positive electrode contains Li6PS5Cl as the solid electrolyte and LiNi as the positive electrode active material. 0.8 Co 0.1 Mn 0.1 O2, carbon black as a conductive material, and butadiene rubber as a binder were used. These were mixed with the solvent o-xylene to produce a slurry for forming the positive electrode. This slurry was then applied to aluminum foil, which served as the positive electrode current collector, using a doctor blade, and dried at 120°C for 10 minutes.

[0108] Next, Li6PS5Cl as the solid electrolyte to be placed on the positive electrode and butadiene rubber as the binder were mixed with o-xylene as the solvent, and then coated onto the positive electrode. The mixture was dried at 120°C for 10 minutes to form a positive electrode laminate on the positive electrode. The positive electrode laminate was then vacuum dried at 120°C for 4 hours.

[0109] The electrodes from Manufacturing Example 1 were arranged so that they faced upwards, and a positive electrode with a positive electrode laminate formed on top of the electrodes was laminated so that the positive electrode laminate faced the positive electrode laminate. Then, a negative electrode-less all-solid-state battery was manufactured by rolling it using a warm isotactic press at 90°C and 450 MPa.

[0110] Example 2 - Manufacturing of a negative electrode-less all-solid-state battery including the electrodes of Manufacturing Example 2 In Example 1, the electrode was manufactured in the same manner as in Example 1, except that the electrode from Manufacturing Example 2 was used instead of the electrode from Manufacturing Example 1.

[0111] Example 3 - Manufacturing of a negative electrode-less all-solid-state battery including the electrodes of Manufacturing Example 3 In Example 1, the electrode was manufactured in the same manner as in Example 1, except that the electrode from Manufacturing Example 3 was used instead of the electrode from Manufacturing Example 1.

[0112] Example 4 - Manufacturing of a negative electrode-less all-solid-state battery including the electrodes of Manufacturing Example 4 In Example 1, the electrode was manufactured in the same manner as in Example 1, except that the electrode from Manufacturing Example 4 was used instead of the electrode from Manufacturing Example 1.

[0113] Example 5 - Manufacturing of a negative electrode-less all-solid-state battery including the electrodes of Manufacturing Example 5 In Example 1, the electrode was manufactured in the same manner as in Example 1, except that the electrode from Manufacturing Example 5 was used instead of the electrode from Manufacturing Example 1.

[0114] Comparative Example 1 - Manufacturing of a negative electrode-less all-solid-state battery including the electrode of Comparative Manufacturing Example 1. Except for using the electrode from Comparative Manufacturing Example 1 instead of the electrode from Manufacturing Example 1 in Example 1, the manufacturing process was the same as in Example 1.

[0115] Comparative Example 2 - Manufacturing of a negative electrode-less all-solid-state battery including the electrode of Comparative Manufacturing Example 2. Except for using the electrode from Comparative Manufacturing Example 2 instead of the electrode from Manufacturing Example 1 in Example 1, the manufacturing process was the same as in Example 1.

[0116] Experimental Example 1 - Evaluation of Initial Performance and Durability Characteristics The negative electrode-less all-solid-state batteries produced in Examples 1-5, Comparative Example 1, and Comparative Example 2 were sealed at a pressure of 2.7 MPa to produce pouch-type lithium secondary batteries.

[0117] Using the aforementioned pouch-type lithium secondary battery, the battery was charged to 4.25V in CC (0.1C) mode at 30°C, then discharged to 2.0V at 0.1C to perform an activation process (formation). Next, the battery was charged to 4.25V in CC (0.33C) mode at 30°C, and then discharged to 2.0V at 0.33C, which constituted one cycle. The discharge capacity (mAh / g), efficiency (%), average discharge voltage (V), and internal resistance were measured and are shown in Table 1 below.

[0118] Next, the charge-discharge cycle was performed 100 times under the same conditions as described above.

[0119] Furthermore, the capacity retention rate (%) for the negative electrode-less all-solid-state batteries manufactured in Examples 1 to 5, Comparative Example 1, and Comparative Example 2 was measured after 30, 50, and 100 charge-discharge cycles, and the Coulomb efficiency was calculated using the following formula, as shown in Table 1 below.

[0120] Coulomb efficiency (%) = (discharge capacity) / (charge capacity) * 100

[0121] Figures 3a to 3c show the capacity retention rate (%) measured for each number of charge-discharge cycles during 100 charge-discharge cycles for the negative electrode-less all-solid-state batteries manufactured in Example 1, Comparative Example 1, and Comparative Example 2 described above.

[0122] [Table 1]

[0123] As shown in Table 1 above, the negative electrode-less all-solid-state batteries of Examples 1 to 5 were confirmed to have high initial discharge capacity and average discharge voltage, as well as low internal resistance and excellent efficiency. This confirmed that during charging, lithium ions uniformly electrodeposited within the voids of the matrix were uniformly desorbed, resulting in complete discharge.

[0124] Furthermore, as shown in Table 1 and Figure 3a, the negative electrode-less all-solid-state batteries of Examples 1 to 5 maintained a capacity retention rate of over 88% and achieved a Coulomb efficiency of over 99.7% after 100 charge-discharge cycles in terms of durability evaluation. This confirmed that as the charge-discharge cycle progressed, silver (Ag) and metal oxide (ZnO) were uniformly dispersed within the matrix of the intermediate layer, suppressing layer separation between silver (Ag) and carbon and maintaining a stable interface. The lithium oxide (Li2O) formed in the matrix led to active lithium diffusion even under room temperature conditions, improving lithium diffusion kinetics, and resulting in active lithium ion movement during charge and discharge, improving durability and lifespan characteristics.

[0125] On the other hand, the negative electrode-less all-solid-state battery of Comparative Example 1 had low initial discharge capacity and efficiency, and it was confirmed that its initial performance was relatively lower compared to Examples 1 to 5. Furthermore, as shown in Table 1 and Figure 3b, in terms of durability evaluation, the negative electrode-less all-solid-state battery of Comparative Example 1 tended to not achieve complete discharge, and the capacity retention rate decreased sharply, showing a low capacity retention rate of less than 20% after approximately 20 charge-discharge cycles. This confirmed that, in the case of the negative electrode-less all-solid-state battery of Comparative Example 1, during discharge, the electrodeposited lithium randomly desorbed and separated at the interface with the solid electrolyte, and under the condition of low fastening pressure per pouch cell, it was difficult for the separated interface to recover, resulting in a complete discharge not occurring.

[0126] The negative electrode-less all-solid-state battery of Comparative Example 2 had a discharge capacity and average discharge voltage at a similar level to Examples 1-5, but it was confirmed that its internal resistance was relatively higher and its efficiency was lower. Furthermore, as shown in Table 1 and Figure 3c, in terms of durability evaluation, the negative electrode-less all-solid-state battery of Comparative Example 2 showed a greater decrease in capacity retention rate as the charge-discharge cycle progressed compared to the negative electrode-less all-solid-state batteries of Examples 1-5, and was confirmed to have a relatively lower capacity retention rate and Coulomb efficiency. As a result, in the case of the negative electrode-less all-solid-state battery of Comparative Example 2, only silver forming a solid solution with lithium in the matrix was present, causing layer separation between carbon and silver. Consequently, the lithium electrodeposited beneath the carbon layer by the silver exhibited low lithium diffusion kinetics in the carbon region under room temperature conditions, preventing complete discharge and confirming the formation of an unstable interface.

[0127] Experimental Example 2 - Analysis of the matrix surface by XPS measurement Before operating the negative electrode-less all-solid-state battery of Example 1, the matrix surface components were analyzed by XPS measurement in the initial charged state (4.25V, SOC 100) and the discharged state (2.5V, SOC 0). After fixing the negative electrode-less all-solid-state battery of Example 1 to a silicon wafer with copper tape, five or more locations were scanned by X-ray photoelectron spectroscopy (XPS), and the results are shown in Figures 4a to 4i.

[0128] As shown in Figures 4a to 4i, before operation of the negative electrode-less all-solid-state battery of Example 1, the presence of silver (Ag) and zinc oxide (ZnO) was confirmed, and in the charged state, lithium-zinc alloy (Li x Zinc (Zn) and lithium oxide (Li2O) were detected, but silver (Ag) was not. In the discharged state, zinc (Zn), silver (Ag), and lithium oxide (Li2O) were detected. This means that during charging, zinc oxide (ZnO) in the matrix reacts with lithium ions to form a lithium-zinc alloy (Li xIt can be confirmed that Zn) and lithium oxide (Li2O) are formed, and that silver (Ag) diffuses and moves to the lithium electrodeposited layer located in the lower part of the matrix, and during discharge, lithium-zinc alloy (Li x We were able to confirm that Zn separated into its respective metallic elements, silver (Ag) diffused to the matrix surface, and Li2O remained intact in the carbon layer because it is an irreversible product.

[0129] Experimental Example 3 - Comparison of Lithium Ion Diffusion Coefficients (1) For the electrode of manufacturing example 1 and the electrode of comparative manufacturing example 2, the lithium ion diffusion coefficient D of the electrode itself Li To compare, half-cells were manufactured and evaluated. Here, the half-cells used Li6PS5Cl and lithium metal as electrodes and solid electrolytes in Manufacturing Example 1 and Comparative Manufacturing Example 2 of the present invention, and the lithium ion diffusion coefficient D Li The lithium ion diffusion coefficient D was determined using the galvanostatic intermittent titration technique (GITT) at 30°C, by referring to the change in voltage when the current was applied as shown in Figure 5a, according to the following mathematical formula 1. Li I calculated it.

[0130] [Mathematical formula 1]

number

[0131] r p :Average particle diameter (50nm) t p Current application time (10 min) E4-E0: Difference between initial voltage and rest (normal state) voltage E2-E1: Voltage difference during current application

[0132] As shown in Figures 5b to 5d, the voltage difference (E2-E1) during current application at the electrode of Manufacturing Example 1 was lower than that of the electrode of Comparative Manufacturing Example 2. This confirmed that the lithium ion diffusion coefficient of the electrode of Manufacturing Example 1 was improved by approximately 2.7 times on average compared to that of the electrode of Comparative Manufacturing Example 2. This means that in the case of the electrode of Manufacturing Example 1, silver (Ag) and zinc oxide (ZnO) are uniformly dispersed as dual seeds in the matrix, lithium ions in the matrix are uniformly electrodeposited inside the voids of the matrix, and a sufficient lithium ion diffusion coefficient can be secured even under room temperature (30°C) conditions. This means that during charging and discharging, short circuits do not occur due to the active movement of lithium ions, and stable battery operation is possible.

[0133] Experimental Example 4 - Comparison of Lithium Ion Diffusion Coefficients (2) To compare the lithium ion diffusion coefficient of the electrodes themselves for Manufacturing Example 1 and Comparative Manufacturing Example 2, half-cells were manufactured and evaluated. Here, the half-cells used the electrodes from Manufacturing Example 1 and Comparative Manufacturing Example 2, with Li6PS5Cl and lithium metal as the solid electrolyte. The lithium ion diffusion coefficient was measured using cyclic voltammetry (CV) at 30°C, with a measurement voltage of 0.5V. The initial scan speed was 0.5mV / S, and the scan speed was doubled every 10 seconds as the step progressed. The current density was measured at the scan speed, and the lithium ion diffusion coefficient D was calculated using the Randles-Sevcik equation (Equation 2 below). Li This was indirectly confirmed, and the results are shown in Figures 6a to 6f.

[0134] [Mathematical formula 2]

number

[0135] i p : Peak current value (A) n: Number of electrons that participated in the Redox reaction A: Electrode area (cm 2 ) D: Diffusion coefficient (cm) 2 / s) C: Concentration (mol / cm 3 ) v: Scan rate (scan rate, V / S)

[0136] As shown in Figures 6a to 6f, the current density with respect to scanning speed was higher in the electrode of Manufacturing Example 1 compared to Comparative Manufacturing Example 2, and it was confirmed that the lithium-ion diffusion coefficient of the electrode of Manufacturing Example 1 was approximately 2.3 times higher during charging and approximately 2.4 times higher during discharging compared to the lithium-ion diffusion coefficient of the electrode of Comparative Manufacturing Example 2. As a result, it was confirmed that in the case of the electrode of Manufacturing Example 1, a sufficient lithium-ion diffusion coefficient can be secured even under room temperature (30°C) conditions, and that no short circuit occurs during charging and discharging even at room temperature, enabling stable battery operation.

[0137] Experimental Example 5 - Comparison of Lithium Ion Diffusion Coefficients (3) Electrochemical evaluations were performed to compare the lithium-ion diffusion coefficients of the negative electrode-less all-solid-state batteries of Example 1 and Comparative Example 2. The difference in lithium-ion diffusion coefficients was indirectly confirmed using a type of overvoltage value called voltage relaxation. Generally, the lower the overvoltage value, the higher the lithium-ion diffusion coefficient relatively; therefore, the lithium-ion diffusion coefficients were compared using the calculated overvoltage values.

[0138] Voltage Relaxation = (Voltage immediately after current application ends - Voltage under normal conditions)

[0139] As shown in Figures 7a and 7b, in the case of the negative electrode-less all-solid-state battery of Example 1, it was possible to indirectly confirm that a lower overvoltage was applied and the lithium-ion diffusion coefficient was higher compared to the negative electrode-less all-solid-state battery of Comparative Example 2.

[0140] Experimental Example 6 - Volume Expansion Relaxation Effect To confirm the volume expansion mitigation effect during charging of a negative electrode-less all-solid-state battery, nine arbitrary points were placed on the negative electrode-less all-solid-state battery of Example 1 and the negative electrode-less all-solid-state battery of Comparative Example 2. The average value and deviation of the difference in thickness between the initial and charged states were measured, and the change in thickness per unit of electrical capacity was calculated to confirm the volume expansion mitigation effect. The experimental results are shown in Tables 2 to 5 below.

[0141] [Table 2]

[0142] [Table 3]

[0143] [Table 4]

[0144] [Table 5]

[0145] As shown in Tables 2 to 5 above, the negative electrode-less all-solid-state battery of Example 1 had lower average and deviation values ​​for the increase in thickness per unit of electrical capacity before and after charging compared to the negative electrode-less all-solid-state battery of Comparative Example 2. It was confirmed that the increase in thickness per unit of electrical capacity of the negative electrode-less all-solid-state battery of Example 1 was reduced by approximately 10.82% [(5.49-4.89) / 5.49*100] compared to the negative electrode-less all-solid-state battery of Comparative Example 2. This is expected to be because zinc (Zn), a lithium-affinity metal, is dispersed inside the carbon region of the negative electrode-less all-solid-state battery, and the lithium oxide (Li2O) formation reaction is induced during charging, causing lithium ions to uniformly electrodeposit in the voids of the carbon region, thus relatively mitigating the effect of volume expansion.

[0146] Experimental Example 7 - Confirmation of lithium electrodeposition location within the electrode and evaluation of volume expansion mitigation effect To confirm the lithium electrodeposition position within the electrodes and evaluate the volume expansion mitigation effect in the charged state of the negative electrode-less all-solid-state battery of Example 1, the cross-section of the negative electrode-less all-solid-state battery in its initial state and 3.3 mAh / cm² were measured. 2 By applying a current and fully charging (SOC 100), the cross-sections of the negative electrode-less all-solid-state batteries were analyzed by SEM (Hitachi Corporation) imaging, and the results are shown in Figures 8a and 8b.

[0147] As shown in Figures 8a and 8b, in a cross-section of the negative electrode-less all-solid-state battery of Example 1 in a fully charged state, a lithium deposition layer was formed in the region below the carbon layer within the intermediate layer, confirming that lithium was uniformly electrodeposited on both the carbon layer and the Li deposition layer. Furthermore, the electrode thickness after charging (sum of the thicknesses of the carbon layer and the Li deposition layer) was approximately 19.0 μm, an increase of approximately 11.4 μm compared to the initial state (approximately 7.6 μm), and the thickness increase per electrodeposition capacity was confirmed to be 3.45 μm / mAh (11.4 μm / 3.3 mAh).

[0148] Experimental Example 8 - Evaluation of rate-limiting properties of metals and metal oxides based on particle size Using the negative electrode-less all-solid-state batteries manufactured in Examples 1-5, the batteries were charged to 4.25V with a constant current of 0.2C in CC / CV mode at 30°C, then discharged to 2V at 0.2C (pre-cycle), and the initial discharge capacity was measured.

[0149] Next, 3 th ~5 th The charge-discharge cycle is 0.2C (first phase), 6 th~8th The charge-discharge cycle is 0.33C (second phase), 9 th ~11 th Up to the charge-discharge cycle, the current is 0.5C (third phase), 12 th ~14 th Up to the charge-discharge cycle, it's 1.0C (4th section), 15 th ~20 thCharge and discharge were performed at 0.2C (5th section) until the charge-discharge cycle was completed. The ratio of the discharge capacity of a specific cycle corresponding to each section of each example to the initial discharge capacity of Example 1 ((discharge capacity of the specific cycle / initial discharge capacity of Example 1) × 100) was calculated, and the results are shown in Table 6 and Figures 9a to 9d.

[0150] [Table 6]

[0151] Referring to Table 6 and Figures 9a to 9d, it was confirmed that the negative electrode-less all-solid-state battery according to Example 1 showed further improvement in rate-limiting characteristics under high current density (C-rate) conditions of 1C compared to the negative electrode-less all-solid-state batteries according to Examples 2 and 4, and that the decrease in discharge capacity was suppressed when returning to a low current density (C-rate) of 0.2C.

[0152] This is interpreted as follows: when the particle size of silver (Ag) or zinc oxide (ZnO) particles electrodeposited in a dual-seed configuration within the matrix voids falls within an optimal range, aggregation into secondary particles due to van der Waals attraction is suppressed, further improving the electrochemical reactivity of lithium ions, optimizing the specific surface area of ​​the silver (Ag) or zinc oxide (ZnO) particles to expand electron transport pathways and reduce electrode resistance.

[0153] Specifically, compared to Examples 2 and 4, in which the particle sizes of silver (Ag) particles or zinc oxide (ZnO) particles are relatively small, Example 1 is interpreted as having reduced aggregation between primary particles due to van der Waals forces during the slurry dispersion process, resulting in the formation of secondary particles with relatively smaller particle sizes, and thus improving the participation of the electrochemical reaction between the formed secondary particles and lithium.

[0154] Furthermore, compared to Examples 3 and 5, in which the particle sizes of silver (Ag) particles or zinc oxide (ZnO) particles are relatively large, Example 1 is interpreted as having improved discharge capacity, particularly a smaller decrease in capacity at high current densities (C-rate), because the entire dual-seed particle can easily participate in the electrochemical reaction with lithium. [Explanation of symbols]

[0155] 10 electrodes 11 Current collector 12 Middle Class 20 Solid electrolyte layer 30 positive electrode

Claims

1. Current collector and, The current collector includes an intermediate layer disposed on the current collector, The aforementioned intermediate layer is A matrix containing carbon material, Dispersed in the aforementioned matrix are lithium-alloyable metallic elements, lithium-alloyable metalloid elements, or combinations thereof, An electrode comprising, dispersed in the matrix, a lithium-alloyable metal oxide, a lithium-alloyable metal fluoride, a lithium-alloyable metallomate oxide, a lithium-alloyable metallomate fluoride, or a combination thereof.

2. The carbon material mentioned above is carbon black, acetylene black, Ketjen black, panel black, furnace black, lamp black, thermal black, natural graphite, artificial graphite, graphene, fullerene (C ６０ The electrode according to claim 1, wherein the electrode is one or more selected from the group consisting of single-wall carbon nanotubes, multi-wall carbon nanotubes, vapor-grown carbon fibers, carbon felt, and carbon paper.

3. The electrode according to claim 1, wherein the carbon material includes amorphous carbon.

4. The electrode according to claim 1, wherein the lithium-alloyable metallic element, lithium-alloyable metalloid element, or combination thereof is one or more selected from the group consisting of Ag, Mg, Zn, Au, Sn, Ge, In, Si, Ga, Al, Sb, Pb, Bi, and Cd.

5. The electrode according to claim 1, wherein the lithium-alloyable metal oxide, lithium-alloyable metal fluoride, lithium-alloyable metallomate oxide, lithium-alloyable metallomate fluoride, or combination thereof is an oxide or fluoride in which one or more metal elements or metallomate elements selected from the group consisting of Ag, Mg, Zn, Au, Sn, Ge, In, Si, Ga, Al, Sb, Pb, Bi, and Cd can be stoichiometrically composed.

6. The electrode according to claim 1, wherein the carbon material has an average particle size greater than the average particle size of particles contained in the lithium-alloyable metallic element, lithium-alloyable metalloid element, or combination thereof, and lithium-alloyable metal oxide, lithium-alloyable metal fluoride, lithium-alloyable metalloid oxide, lithium-alloyable metalloid fluoride, or combination thereof.

7. The electrode according to claim 1, wherein the carbon material includes a carbon material having an average particle size of 1 nm or more and 100 μm or less.

8. The electrode according to claim 1, wherein the average particle size of the particles contained in the lithium-alloyable metallic element, lithium-alloyable metalloid element, or combination thereof is 1 nm or more and 100 μm or less.

9. The electrode according to claim 1, wherein the average particle size of the particles contained in the lithium-alloyable metal oxide, lithium-alloyable metal fluoride, lithium-alloyable metallomate oxide, lithium-alloyable metallomate fluoride, or combination thereof is 1 nm or more and 100 μm or less.

10. The electrode according to claim 1, wherein the intermediate layer contains the metal element, metalloid element or a combination thereof, and the metal oxide, metal fluoride, metalloid oxide, metalloid fluoride or a combination thereof in a content of more than 0% by weight and 50% by weight or less.

11. The electrode according to claim 1, wherein the intermediate layer contains the metal element, metalloid element or a combination thereof and the metal oxide, metal fluoride, metalloid oxide, metalloid fluoride or a combination thereof in a weight ratio of 1:0.1 to 9.

12. The aforementioned intermediate layer comprises a matrix containing amorphous carbon, Ag dispersed in the aforementioned matrix, The electrode according to claim 1, comprising ZnO dispersed in the matrix.

13. The intermediate layer is composed of Li distributed in the matrix ２ O and, Li distributed in the matrix ｘ The electrode according to claim 12, further comprising Zn (where x is 0 ≤ x ≤ 1).

14. The electrode according to claim 1, wherein the electrode has a thickness of 1 μm or more and 100 μm or less.

15. Current collector and, The current collector includes an intermediate layer disposed on the current collector, The aforementioned intermediate layer is A matrix containing carbon material, Dispersed in the aforementioned matrix are lithium-alloyable metallic elements, lithium-alloyable metalloid elements, or combinations thereof, Li distributed in the matrix ２ An electrode containing oxygen.

16. A step of mixing carbon material, inorganic elements, inorganic compounds, binder and solvent to produce a slurry, The steps include applying the slurry to at least one surface of the current collector, Includes a drying step, The inorganic element includes a metallic element that can be alloyed with lithium, a metalloid element that can be alloyed with lithium, or a combination thereof. A method for manufacturing an electrode, wherein the inorganic compound includes a lithium-alloyable metal oxide, a lithium-alloyable metal fluoride, a lithium-alloyable metallomate oxide, a lithium-alloyable metallomate fluoride, or a combination thereof.

17. It includes a positive electrode, a negative electrode, and a solid electrolyte layer disposed between the positive electrode and the negative electrode, The positive electrode includes a positive electrode active material layer containing a positive electrode active material, The negative electrode is the electrode described in any one of claims 1 to 15. The solid electrolyte layer is disposed between the positive electrode active material layer and the intermediate layer in a negative electrode-less all-solid-state battery.

18. The negative electrode-less all-solid-state battery according to claim 17, wherein the positive electrode active material includes a lithium transition metal composite oxide.

19. The negative electrode-less all-solid-state battery according to claim 17, wherein the solid electrolyte layer comprises a sulfide-based solid electrolyte.

20. The negative electrode-less all-solid-state battery according to claim 19, wherein the sulfide-based solid electrolyte includes an argyrodite-type sulfide-based solid electrolyte.

21. The negative electrode-less all-solid-state battery according to claim 17, wherein when the negative electrode-less all-solid-state battery is charged 100 times or more, one or more elements selected from the group consisting of lithium and Ag are deposited between the intermediate layer and the current collector.

22. The negative electrode-less all-solid-state battery according to claim 17, wherein the thickness of the negative electrode is 5 μm or more and 100 μm or less when it has been charged 100 times or more.

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