Negative electrode for lithium metal battery, lithium metal battery including same, and method for manufacturing negative electrode for lithium metal battery

Abstract

Provided are a negative electrode for a lithium metal battery, a lithium metal battery including same, and a method for manufacturing a negative electrode for a lithium metal battery. The negative electrode comprises: a negative electrode current collector; and an electrodeposition-inducing layer disposed on the negative electrode current collector. The electrodeposition-inducing layer includes a first electrodeposition-inducing layer and a second electrodeposition-inducing layer disposed between the first electrodeposition-inducing layer and the negative electrode current collector, the first electrodeposition-inducing layer includes a metal, and the second electrodeposition-inducing layer includes a conductive polymer.

Description

Anode for a lithium metal battery, a lithium metal battery including the same, and a method for manufacturing anode for a lithium metal battery

[0001] The present invention relates to a negative electrode for a lithium metal battery, a lithium metal battery including the same, and a method for manufacturing the negative electrode for a lithium metal battery.

[0002] Lithium batteries currently on the market primarily use carbon-based anode materials, such as graphite. Carbon-based anode materials exhibit no volume change during charge and discharge, contributing to the stability of lithium batteries. Graphite's theoretical capacity is relatively small, at around 372 mAh / g.

[0003] Lithium metal can be used as an anode active material. Lithium metal has a very high theoretical electrical capacity of approximately 3860 mAh / g. During charge / discharge, lithium metal can form dendrites on its surface due to side reactions with the electrolyte. These dendrites can then grow and cause short circuits between the anode and cathode. Consequently, the lifespan of lithium metal batteries containing lithium metal deteriorates.

[0004] A method for improving the life characteristics of a lithium metal battery containing lithium metal is required.

[0005] One aspect is to provide a new structure of cathode for lithium metal batteries.

[0006] Another aspect is to provide a lithium metal battery comprising a cathode of a novel structure.

[0007] Another aspect is to provide a method for manufacturing a negative electrode for a lithium metal battery of a new structure.

[0008] According to the implementation example

[0009] A cathode current collector; and an electrodeposition induction layer disposed on the cathode current collector;

[0010] The above electrodeposition-inducing layer includes a first electrodeposition-inducing layer and a second electrodeposition-inducing layer disposed between the first electrodeposition-inducing layer and the negative electrode current collector,

[0011] The above first electrodeposition induction layer includes a metal,

[0012] A negative electrode for a lithium metal battery is provided, wherein the second electrodeposition-inducing layer includes a conductive polymer.

[0013] According to another implementation example

[0014] A cathode comprising a cathode current collector; and a cathode active material layer on one surface of the cathode current collector;

[0015] the above cathode; and

[0016] A lithium metal battery is provided, including an electrolyte layer disposed between the positive electrode and the negative electrode.

[0017] According to another implementation example,

[0018] A step of providing a negative electrode collector;

[0019] A step of providing a cathode collector to a spin coater;

[0020] A step of coating a solution containing a conductive polymer on the negative electrode collector provided to the spin coater to provide a second electrodeposition-inducing layer containing a conductive polymer on the negative electrode collector; and

[0021] A method for manufacturing a lithium metal battery is provided, comprising the step of immersing a negative electrode current collector on which a second electrodeposition-inducing layer is formed in a solution containing a metal to provide a first electrodeposition-inducing layer on the second electrodeposition-inducing layer.

[0022] According to one aspect, it is possible to provide a lithium metal battery with improved cycle characteristics by adopting a negative electrode for a lithium metal battery having a new structure.

[0023] Figures 1a and 1b are cross-sectional views of a cathode according to an exemplary embodiment.

[0024] Figure 2 is a cross-sectional view of a cathode according to another exemplary embodiment.

[0025] Figure 3 is a cross-sectional view of a cathode according to another exemplary embodiment.

[0026] Figure 4 is a cross-sectional view of a cathode according to another exemplary embodiment.

[0027] Figures 5a and 5b are scanning electron microscope (SEM) images of the cross-sections of the cathodes of Example 1 and Comparative Example 1.

[0028] Figure 6 is a graph showing the XRD spectra of the cathodes of Example 1 and Comparative Example 1.

[0029] Figure 7 is a graph showing the charge / discharge curve of Example 1.

[0030] Figure 8 is a graph showing the life characteristics of lithium metal batteries manufactured in Example 1, Comparative Example 1, and Comparative Example 2.

[0031] Figure 9 is a drawing showing the coating state of a cathode including an electrodeposition-inducing layer manufactured in Example 1 and Comparative Example 3.

[0032] Figure 10 is a drawing showing the coating state of a cathode including an electrodeposition-inducing layer manufactured in Example 1 and Comparative Example 4.

[0033] Figure 11 is a drawing showing the contact angle of the electrodeposition-inducing layer manufactured in Example 1 and Comparative Example 5.

[0034] Figure 12 is a scanning electron microscope (SEM) image of the cathode cross-section of Reference Example 1.

[0035] Figure 13 is a scanning electron microscope (SEM) image of the cathode cross-section of Reference Example 2.

[0036] Figure 14 is a scanning electron microscope (SEM) image of the cathode cross-section of Reference Example 3.

[0037] Figure 15 is a cross-sectional schematic diagram of a lithium metal battery according to an exemplary embodiment.

[0038] Figure 16 is a cross-sectional schematic diagram of a lithium metal battery according to an exemplary embodiment.

[0039] Figure 17 is a schematic diagram of a lithium metal battery according to an exemplary embodiment.

[0040] Figure 18 is a schematic diagram of a lithium metal battery according to an exemplary embodiment.

[0041] Figure 19 is a schematic diagram of a lithium metal battery according to an exemplary embodiment.

[0042] Figure 20 is a schematic diagram of a lithium metal battery according to an exemplary embodiment.

[0043] Unless otherwise defined, all terms (including technical and scientific terms) used in this disclosure have the same meaning as commonly understood by those of ordinary skill in the art to which this disclosure pertains. Furthermore, terms defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning within the context of the relevant technology and this disclosure, and should not be interpreted in an idealized or overly formal sense.

[0044] Exemplary embodiments are described in this disclosure with reference to cross-sectional drawings that are schematic representations of idealized embodiments. As such, variations from the shapes depicted are to be expected, for example, as a result of manufacturing techniques and / or tolerances. Therefore, the embodiments described in this disclosure should not be construed as limited to the specific shapes of regions as depicted in this disclosure, but should encompass variations in shapes resulting from, for example, manufacturing. For example, regions depicted or described as flat may typically have rough and / or non-linear features. Moreover, angles depicted as sharp may be rounded. Therefore, the regions depicted in the drawings are schematic in nature, and their shapes are not intended to depict the precise shapes of the regions, nor are they intended to limit the scope of the claims.

[0045] This creative idea may be embodied in many different forms and should not be construed as limited to the embodiments described in this disclosure. These embodiments are provided so that this disclosure will be thorough and complete, and so that it will fully convey the scope of the creative idea to those skilled in the art. Like reference numerals in the drawings indicate like elements.

[0046] When a component is referred to as being "on" another component, it can be understood that it is either directly on top of the other component or that other components may be intervening between them. Conversely, when a component is referred to as being "directly on" another component, no intervening components are present.

[0047] Although terms such as "first," "second," "third," etc. may be used herein to describe various components, elements, regions, layers, and / or zones, these components, elements, regions, layers, and / or zones should not be limited by these terms. These terms are only used to distinguish one component, element, region, layer, or zone from another component, element, region, layer, or zone. Thus, a first component, element, region, layer, or zone described below may be referred to as a second component, element, region, layer, or zone without departing from the teachings of this disclosure.

[0048] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used herein, the singular forms "a," "an," and "the" are intended to include the plural forms including "at least one," unless the content clearly dictates otherwise. "At least one" should not be construed as limiting to the singular. As used herein, the term "and / or" includes any and all combinations of one or more of the listed items. The terms "comprises" and / or "comprising" as used in the detailed description specify the presence of stated features, regions, integers, steps, operations, components, and / or ingredients, but do not preclude the presence or addition of one or more other features, regions, integers, steps, operations, components, ingredients, and / or groups thereof.

[0049] Spatially relative terms such as "below," "under," "lower," "above," "upper," and the like may be used herein to readily describe the relationship of one component or feature to another. It will be understood that spatially relative terms are intended to encompass different orientations of the device when in use or operation in addition to the orientations depicted in the drawings. For example, if the device in the drawings were turned over, a component described as "below" or "below" another component or feature would then be oriented "above" the other component or feature. Thus, the exemplary term "below" can encompass both the above and below orientations. The device may be arranged in other orientations (rotated 90 degrees or otherwise rotated), and the spatially relative terms used herein may be interpreted accordingly.

[0050] "Group" means a group in the periodic table of elements according to the International Union of Pure and Applied Chemistry ("IUPAC") Group 1-18 classification system.

[0051] In this disclosure, “particle diameter” refers to the average diameter when the particle is spherical, and refers to the average major axis length when the particle is non-spherical. The particle diameter can be measured using a particle size analyzer (PSA). The “particle diameter” is, for example, the average particle diameter. The “average particle diameter” is, for example, D50, the median particle diameter.

[0052] D50 is the size of the particle corresponding to 50% of the cumulative volume, calculated from the particle side with a smaller particle size in the particle size distribution measured by laser diffraction.

[0053] D90 is the size of the particle corresponding to 90% of the cumulative volume, calculated from the particle side with a smaller particle size in the particle size distribution measured by laser diffraction.

[0054] D10 is the size of the particle corresponding to 10% of the cumulative volume, calculated from the particle side with a small particle size in the particle size distribution measured by laser diffraction.

[0055] In this disclosure, “metal” includes both metals and metalloids such as silicon and germanium, in their elemental or ionic states.

[0056] In this disclosure, “alloy” means a mixture of two or more metals.

[0057] In the present disclosure, “electrode active material” means an electrode material capable of undergoing lithiation and delithiation.

[0058] In the present disclosure, “positive electrode material” means a positive electrode material capable of undergoing lithiation and delithiation.

[0059] In the present disclosure, “negative electrode active material” means a negative electrode material capable of undergoing lithiation and delithiation.

[0060] In the present disclosure, “lithiation” and “lithiating” mean a process of adding lithium to an electrode active material.

[0061] In the present disclosure, “delithiation” and “delithiate” mean a process of removing lithium from an electrode active material.

[0062] In this disclosure, “charging” and “charging” mean a process of providing electrochemical energy to a battery.

[0063] In this disclosure, “discharging” and “discharging” mean the process of removing electrochemical energy from a battery.

[0064] In the present disclosure, “positive electrode” and “cathode” mean an electrode at which electrochemical reduction and lithiation occur during a discharge process.

[0065] In the present disclosure, “cathode” and “anode” mean electrodes where electrochemical oxidation and delithiation occur during a discharge process.

[0066] While specific implementations have been described, alternatives, modifications, variations, improvements, and substantial equivalents that are not currently anticipated or unforeseen may occur to the applicant or those skilled in the art. Accordingly, the appended claims, as filed and as amended, are intended to encompass all such alternatives, modifications, variations, improvements, and substantial equivalents.

[0067] Hereinafter, a negative electrode for a lithium metal battery, a lithium metal battery including the same, and a method for manufacturing a lithium metal battery according to exemplary embodiments are described in more detail.

[0068] [cathode]

[0069] According to one embodiment, a negative electrode for a lithium metal battery includes: an negative electrode current collector; and an electrodeposition-inducing layer disposed on the negative electrode current collector. The electrodeposition-inducing layer includes a first electrodeposition-inducing layer and a second electrodeposition-inducing layer disposed between the first electrodeposition-inducing layer and the negative electrode current collector. The first electrodeposition-inducing layer includes a metal. The second electrodeposition-inducing layer includes a conductive polymer.

[0070] The first electrodeposition-inducing layer of the negative electrode for a lithium metal battery includes a metal, thereby forming an alloy with lithium, thereby suppressing the precipitation of lithium dendrites during charge and discharge and allowing lithium to be uniformly deposited. Consequently, the cycle characteristics of the lithium metal battery are improved.

[0071] The second electrodeposition-inducing layer of a negative electrode for a lithium metal battery can alleviate the surface roughness of the negative electrode current collector by including a conductive polymer. The conductive polymer can reduce the metal contained in the first electrodeposition-inducing layer and smoothly arrange it on the second electrodeposition-inducing layer. The conductive polymer has excellent affinity for lithium, thereby suppressing the precipitation of lithium dendrites and inducing uniform lithium deposition. Consequently, the cycle characteristics of the lithium metal battery are improved.

[0072] FIGS. 1A, 1B, and 2 to 4 are cross-sectional schematic views of a negative electrode for a lithium battery according to one embodiment.

[0073] Referring to FIGS. 1A and 1B, the negative electrode (20) includes a negative electrode current collector (21); and an electrodeposition induction layer (22) disposed on the negative electrode current collector (21), and the electrodeposition induction layer (22) includes a first electrodeposition induction layer (22a) and a second electrodeposition induction layer (22b) disposed between the first electrodeposition induction layer (22a) and the negative electrode current collector (21). Referring to FIG. 2, the negative electrode (20) includes a negative electrode current collector (21); an negative electrode active material layer (23) disposed on the negative electrode current collector (21); And it includes an electrodeposition induction layer (22) disposed between the negative electrode current collector (21) and the negative electrode active material layer (23), and the electrodeposition induction layer (22) includes a first electrodeposition induction layer (22a) and a second electrodeposition induction layer (22b) disposed between the first electrodeposition induction layer (22a) and the negative electrode current collector (21).

[0074] [Cathode: Electrodeposition-inducing layer]

[0075] Referring to FIGS. 1A, 1B, and 2 to 4, the negative electrode (20) includes a negative electrode current collector (21); and an electrodeposition-inducing layer (22) disposed on the negative electrode current collector (21). The electrodeposition-inducing layer (22) includes a first electrodeposition-inducing layer (22a) and a second electrodeposition-inducing layer (22b) disposed between the first electrodeposition-inducing layer (22a) and the negative electrode current collector (21). The electrodeposition-inducing layer (22) can effectively prevent the generation and / or growth of lithium dendrites on the surface of the electrodeposition-inducing layer (22) and / or the negative electrode active material layer (23) including lithium metal.

[0076] The first electrodeposition-inducing layer (22a) may include a metal, for example, the first electrodeposition-inducing layer (22a) may include silver (Ag), gold (Au), platinum (Pt), palladium (Pd), aluminum (Al), bismuth (Bi), tin (Sn), zinc (Zn), or any combination thereof. The first electrodeposition-inducing layer (22a) may also be formed of a metal. Therefore, when the first electrodeposition-inducing layer (22a) is formed of a metal, the shape of the first electrodeposition-inducing layer (22a) may be as described in FIG. 1b, but is not limited thereto. In addition, the shape of the first electrodeposition-inducing layer (22a) formed in FIG. 1b may be applied to all of FIGS. 2 to 4, FIG. 15, and FIG. 16.

[0077] The metal may be in the form of particles. The metal may be uniformly distributed on the second electrodeposition-inducing layer (22b) in the form of particles. The metal may be non-homogeneously distributed on the second electrodeposition-inducing layer (22b) in the form of particles. The metal may be uniformly distributed on the second electrodeposition-inducing layer (22b) in the form of particles to form the first electrodeposition-inducing layer (22a). The metal may be non-homogeneously distributed on the second electrodeposition-inducing layer (22b) in the form of particles to form the first electrodeposition-inducing layer (22a).

[0078] The average particle diameter of the metal particles may be, for example, 150 nm to 250 nm. As the particle diameter of the metal particles satisfies the corresponding range, the lithium dendrite formation suppression characteristics and lithium uniform deposition characteristics of the first electrodeposition-inducing layer (22a) can be further improved.

[0079] The first electrodeposition-inducing layer (22a) may further include a nitrate. For example, the first electrodeposition-inducing layer (22a) may further include silver nitrate, gold nitrate, platinum nitrate, palladium nitrate, aluminum nitrate, bismuth nitrate, tin nitrate, zinc nitrate, or any combination thereof.

[0080] The first electrodeposition induction layer (22a) can be formed by a metal reduced from nitrate.

[0081] The second electrodeposition-inducing layer (22b) includes a conductive polymer. For example, the conductive polymer may be a polymer including an electron-conductive repeating unit, a polymer including an ion-conductive repeating unit, a polymer including an electron-conductive repeating unit and an ion-conductive repeating unit, or any combination thereof.

[0082] The polymer comprising the electron-conducting repeating unit can be, for example, poly(3,4-ethylenedioxythiophene), polyaniline, polypyrrole, polyacetylene, polydopamine, or any combination thereof.

[0083] The polymer comprising the ion-conducting repeating unit can be polyethylene glycol, polypropylene oxide, polyimide, polyamine, polynitrile, or any combination thereof.

[0084] The polymer including the above-mentioned electron-conducting repeating unit and ion-conducting repeating unit may be a copolymer of a polymer including the above-mentioned electron-conducting repeating unit and a polymer including the above-mentioned ion-conducting repeating unit.

[0085] The copolymer includes a block copolymer having a structural block, and the block copolymer may include i) one or more polymers selected from poly(3,4-ethylenedioxythiophene), polyaniline, polypyrrole, polyacetylene, and polydopamine, and ii) one or more polymers selected from polyethylene glycol, polypropylene oxide, polyimide, polyamine, and polynitrile.

[0086] The block copolymer can be, for example, a block copolymer comprising a first block of poly(3,4-ethylenedioxythiophene) and a second block of polyethylene glycol; a block copolymer comprising a first block of poly(3,4-ethylenedioxythiophene), a second block of polyethylene glycol, and a third block of poly(3,4-ethylenedioxythiophene); a block copolymer comprising a first block of polyethylene glycol, a second block of poly(3,4-ethylenedioxythiophene), and a third block of polyethylene glycol; a block copolymer comprising a first block of poly(3,4-ethylenedioxythiophene) and a second block of polypropylene oxide; a block copolymer comprising a first block of poly(3,4-ethylenedioxythiophene), a second block of polypropylene oxide, and a third block of poly(3,4-ethylenedioxythiophene); or any combination thereof.

[0087] For example, the block copolymer may comprise poly(3,4-ethylenedioxythiophene) and polyethylene glycol, for example, poly(3,4-ethylenedioxythiophene)-block-polyethylene glycol (PEDOT-block-PEG).

[0088] The thickness of the electrodeposition induction layer (22) may be, for example, 0.1 μm to 25 μm.

[0089] The thickness of the electrodeposition induction layer (22) may be, for example, 0.1 μm to 25 μm, 1 μm to 20 μm, 1 μm to 15 μm, 1 μm to 12 μm, 1 μm to 10 μm, 1 μm to 5 μm, or 1 μm to 2 μm.

[0090] The thickness of the first electrodeposition induction layer (22a) may be, for example, 0.1 μm to 20 μm.

[0091] The thickness of the second electrodeposition induction layer (22b) may be, for example, 0.1 μm to 0.2 μm.

[0092] In the XRD spectrum of the cathode including the electrodeposition-induced layer, the peak at the diffraction angle 2θ=28°±0.5° may have a half-width of 0.1 to 0.5. For example, the half-width may be 0.1 to 0.5, or 0.2 to 0.4.

[0093] Referring to FIGS. 3 and 4, the electrodeposition induction layer (22) can be additionally placed on the side of the negative electrode current collector (21).

[0094] Referring to FIG. 3, the negative electrode (20) includes a negative electrode current collector (21); an electrodeposition-inducing layer (22) disposed on the negative electrode current collector (21), and the electrodeposition-inducing layer (22) includes a first electrodeposition-inducing layer (22a) and a second electrodeposition-inducing layer (22b) disposed between the first electrodeposition-inducing layer (22a) and the negative electrode current collector (21), and the electrodeposition-inducing layer (22) is disposed to extend to at least one side of the negative electrode current collector (21). The electrodeposition-inducing layer (22) can completely cover the side of the negative electrode current collector (21). By extending the electrodeposition-inducing layer (22) to at least one side of the negative electrode current collector (21), uniform electrodeposition of lithium deposited on the electrodeposition-inducing layer (22) can be induced and formation of lithium dendrites can be suppressed.

[0095] [Cathode: Cathode active material layer]

[0096] Referring to FIGS. 1A, 1B, and 3, the negative electrode (20) does not include a negative electrode active material layer (23) disposed on the negative electrode current collector (21) and the electrodeposition induction layer (22). The negative electrode (20) not including the negative electrode active material layer (23) may include a negative electrode active material layer (23) by plating lithium metal on the negative electrode current collector (21) and the electrodeposition induction layer (22) by charging after being introduced into a lithium battery together with the positive electrode and the electrolyte. The negative electrode active material layer may be a lithium plating layer (plated lithium layer). The negative electrode active material layer (23) may include, for example, non-fibrous lithium or non-acidic lithium. The negative electrode active material layer (23) may include, for example, plate-shaped lithium.

[0097] Referring to FIGS. 2 and 4, a negative electrode (20) for a lithium metal battery includes a negative electrode current collector (21); and a negative electrode active material layer (23) disposed on the negative electrode current collector (21), and includes an electrodeposition induction layer (22) disposed between the negative electrode current collector (21) and the negative electrode active material layer (23), wherein the electrodeposition induction layer (22) includes a first electrodeposition induction layer (22a) and a second electrodeposition induction layer (22b) disposed between the first electrodeposition induction layer (22a) and the negative electrode current collector (21). Therefore, the negative electrode active material layer (23) can be disposed between the electrodeposition induction layer (22) and an electrolyte layer (30) to be described later.

[0098] The negative electrode active material layer (23) may be, for example, a metal layer. The negative electrode active material layer (23) may include, for example, lithium metal or a lithium alloy. The negative electrode active material layer (23) may include, for example, lithium foil, lithium powder, plated lithium, a lithium alloy, an organic compound containing lithium, or a combination thereof. The negative electrode active material layer containing lithium foil may be, for example, a lithium metal layer. The negative electrode active material layer containing lithium powder may be introduced by coating a slurry containing lithium powder and a binder, etc., on a negative electrode current collector. The binder may be, for example, a fluorine-based binder such as polyvinylidene fluoride (PVDF). The negative electrode active material layer may not include a carbon-based negative electrode active material. Therefore, the negative electrode active material layer may be formed of a metal-based negative electrode active material. The negative electrode active material layer (23) may include, for example, non-fibrous lithium or non-acidic lithium. The negative electrode active material layer (23) may include, for example, plate-shaped lithium.

[0099] The thickness of the lithium foil may be, for example, 1 μm to 50 μm, 1 μm to 30 μm, or 10 μm to 30 μm, or 10 μm to 80 μm. When the lithium foil has a thickness in this range, the life characteristics of a lithium battery including an electrodeposition-inducing layer may be further improved. The particle size of the lithium powder may be, for example, 0.1 μm to 3 μm, 0.1 μm to 2 μm, or 0.1 μm to 2 μm. When the lithium powder has a thickness in this range, the life characteristics of a lithium battery including an electrodeposition-inducing layer may be further improved.

[0100] The thickness of the negative electrode active material layer (23) may be, for example, 0.1 µm to 100 µm, 0.1 µm to 80 µm, 1 µm to 80 µm, or 10 µm to 80 µm, but is not necessarily limited to this range and may be adjusted according to the shape, capacity, etc. of the required lithium battery.

[0101] [Cathode: Negative current collector]

[0102] The negative electrode current collector (21) is composed of, for example, a material that does not react with lithium, i.e., does not form an alloy or a compound. The material constituting the negative electrode current collector (21) is, for example, copper, nickel, nickel-coated copper, stainless steel (SUS), iron (Fe), cobalt (Co), etc., but is not necessarily limited thereto, and any material that is used as an electrode current collector in the relevant technical field may be used. The negative electrode current collector (21) may be composed of one type of the above-described metal, or may be composed of an alloy or a coating material of two or more types of metals. The negative electrode current collector (21) is, for example, in the form of a plate or foil.

[0103] The negative electrode current collector (21) is not shown in the drawing, but may include, for example, a base film and a metal layer disposed on one or both sides of the base film. The base film may include, for example, a polymer. The polymer may be, for example, a thermoplastic polymer. The polymer may include, for example, polyethylene terephthalate (PET), polyethylene (PE), polypropylene (PP), polybutylene terephthalate (PBT), or a combination thereof. Since the base film includes a thermoplastic polymer, the base film may melt when a short circuit occurs, thereby suppressing a rapid increase in current. The base film may be, for example, an insulator. The metal layer may include, for example, indium (In), copper (Cu), magnesium (Mg), titanium (Ti), iron (Fe), cobalt (Co), nickel (Ni), zinc (Zn), aluminum (Al), germanium (Ge), lithium (Li), or an alloy thereof. In particular, the metal layer may include, for example, copper (Cu), titanium (Ti), iron (Fe), cobalt (Co), nickel (Ni), or an alloy thereof. The metal layer may act as an electrochemical fuse and may be cut off in the event of an overcurrent to prevent a short circuit. The limit current and the maximum current may be controlled by adjusting the thickness of the metal layer. The metal layer may be plated or deposited on the base film. As the thickness of the metal layer decreases, the limit current and / or the maximum current of the negative electrode current collector (21) decrease, thereby improving the stability of the lithium battery in the event of a short circuit. A lead tab may be added on the metal layer for connection to the outside. The lead tab may be welded to the metal layer or the metal layer / base film laminate by ultrasonic welding, laser welding, spot welding, or the like. When welding, the base film and / or the metal layer may be melted, so that the metal layer may be electrically connected to the lead tab.In order to make the welding between the metal layer and the lead tab more robust, a metal chip may be added between the metal layer and the lead tab. The metal chip may be a thin piece of the same material as the metal of the metal layer. The metal chip may be, for example, a metal foil, a metal mesh, etc. The metal chip may be, for example, copper foil, nickel foil, etc. By placing the metal chip on the metal layer and then welding it with the lead tab, the lead tab may be welded to the metal chip / metal layer laminate or the metal chip / metal layer / base film laminate. During welding, the base film, the metal layer, and / or the metal chip may melt, so that the metal layer or the metal layer / metal chip laminate may be electrically connected to the lead tab. The metal chip and / or the lead tab may be added to a portion of the metal layer. The thickness of the base film may be, for example, 1 to 50 ㎛, 1.5 to 50 ㎛, 1.5 to 40 ㎛, or 1 to 30 ㎛. By having a thickness of the base film in this range, the weight of the electrode assembly can be more effectively reduced. The melting point of the base film can be, for example, 100 to 300°C, 100 to 250°C or less, or 100 to 200°C. By having a melting point in this range, the base film can be melted during the process of welding the lead tab and easily bonded to the lead tab. A surface treatment, such as corona treatment, can be performed on the base film to improve the adhesion between the base film and the metal layer. The thickness of the metal layer can be, for example, 0.01 to 3 μm, 0.1 to 3 μm, 0.1 to 2 μm, or 0.1 to μm. By having a thickness of the metal layer in this range, conductivity can be maintained while ensuring the stability of the electrode assembly. The thickness of the metal piece can be, for example, 2 to 10 μm, 2 to 7 μm, or 4 to 6 μm. By having the metal piece in this range of thickness, the connection between the metal layer and the lead tab can be performed more easily.By having this structure, the negative electrode current collector (21) can reduce the weight of the negative electrode and consequently improve the energy density of the all-solid-state secondary battery.

[0104] The negative electrode current collector (21) may further include, for example, a thin film including an element capable of forming an alloy with lithium on one surface of the negative electrode current collector (21), although not shown in the drawing. The thin film is disposed between the negative electrode current collector (21) and the negative electrode active material layer (22). The thin film includes, for example, an element capable of forming an alloy with lithium. The element capable of forming an alloy with lithium includes, but is not limited to, gold, silver, zinc, tin, indium, silicon, aluminum, bismuth, etc., and any element capable of forming an alloy with lithium in the art may be used. The thin film may be composed of one of these metals or an alloy of several types of metals. By placing the thin film on one side of the negative electrode current collector (21), the deposition form of the second negative electrode active material (25) deposited between the thin film (24) and the negative electrode active material layer (22), for example, becomes flatter, and the cycle characteristics of the lithium battery (1) can be further improved.

[0105] The thickness of the thin film is, for example, 1 nm to 800 nm, 10 nm to 700 nm, 50 nm to 600 nm, or 100 nm to 500 nm. If the thickness of the thin film is less than 1 nm, it may be difficult for the function of the thin film to be exerted. If the thickness of the thin film is excessively thick, the thin film itself absorbs lithium, thereby reducing the amount of lithium precipitation from the negative electrode (20), and the cycle characteristics of the lithium battery (1) may deteriorate. The thin film may be disposed on the negative electrode current collector (21) by, for example, a vacuum deposition method, a sputtering method, a plating method, or the like, but is not necessarily limited to these methods, and any method capable of forming a thin film in the relevant technical field may be used.

[0106] [Lithium battery]

[0107] Referring to FIGS. 9 and 10, a lithium battery (1) includes a positive electrode (10) including a positive electrode current collector (11); and a positive electrode active material layer (12) on one surface of the positive electrode current collector (11); the above-described negative electrode (20); and an electrolyte layer (30) disposed between the positive electrode (10) and the negative electrode (20). By having the above-described negative electrode (20), the cycle characteristics of the lithium battery (1) are improved.

[0108] [anode]

[0109] Referring to FIGS. 9 and 10, a lithium battery (1) according to one embodiment includes a positive electrode (10), and the positive electrode (10) includes a positive electrode current collector (11) and a positive electrode active material layer (12) disposed on one surface of the positive electrode current collector (11).

[0110] [Anode: Anode active material layer]

[0111] The cathode active material included in the cathode active material layer (12) is a cathode active material capable of reversibly absorbing and desorbing lithium ions. The cathode active material includes, for example, an oxide-based cathode active material, a sulfide-based cathode active material, or a combination thereof.

[0112] The oxide-based cathode active material includes, for example, a lithium transition metal oxide, a metal oxide, or a combination thereof. The lithium transition metal oxide includes, for example, lithium cobalt oxide, lithium nickel oxide, lithium nickel cobalt oxide, lithium nickel cobalt aluminum oxide, lithium nickel cobalt mangense oxide, lithium manganate, lithium iron phosphate, or a combination thereof. The lithium oxide includes, for example, iron oxide, vanadium oxide, or a combination thereof.

[0113] Sulfide-based cathode active materials include, for example, nickel sulfide, copper sulfide, Li2S, Li2S-containing complexes, or combinations thereof.

[0114] The oxide-based cathode active material may be, for example, at least one compound oxide of lithium and a metal selected from cobalt, manganese, nickel, and combinations thereof, and specific examples thereof include Li a A 1-b B' b D2 (in the above formula, 0.90 ≤ a ≤ 1, and 0 ≤ b ≤ 0.5); Li a E 1-b B' b O 2-c D c (In the above formula, 0.90 ≤ a ≤ 1, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.05); LiE 2-b B' b O 4-c D c (In the above formula, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.05); Li a Ni 1-b-c Co b B' c D α (In the above equation, 0.90 ≤ a ≤ 1, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.05, 0 < α ≤ 2); Li a Ni 1-b-c Co b B' c O 2-α F' α (In the above equation, 0.90 ≤ a ≤ 1, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.05, 0 < α < 2); Li a Ni 1-b-c Co b B' c O 2-α F' α (In the above equation, 0.90 ≤ a ≤ 1, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.05, 0 < α < 2); Lia Ni 1-b-c Mn b B' c D α (In the above equation, 0.90 ≤ a ≤ 1, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.05, 0 < α ≤ 2); Li a Ni 1-b-c Mn b B' c O 2-α F' α (In the above equation, 0.90 ≤ a ≤ 1, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.05, 0 < α < 2); Li a Ni 1-b-c Mn b B' c O 2-α F' α (In the above equation, 0.90 ≤ a ≤ 1, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.05, 0 < α < 2); Li a Ni b E c G d O2 (in the above formula, 0.90 ≤ a ≤ 1, 0 ≤ b ≤ 0.9, 0 ≤ c ≤ 0.5, 0.001 ≤ d ≤ 0.1); Li a Ni b Co c Mn d G e O2 (in the above formula, 0.90 ≤ a ≤ 1, 0 ≤ b ≤ 0.9, 0 ≤ c ≤ 0.5, 0 ≤ d ≤ 0.5, 0.001 ≤ e ≤ 0.1); Li a NiG b O2 (in the above formula, 0.90 ≤ a ≤ 1, 0.001 ≤ b ≤ 0.1); Li a CoG b O2 (in the above formula, 0.90 ≤ a ≤ 1, 0.001 ≤ b ≤ 0.1); Li a MnG b O2 (in the above formula, 0.90 ≤ a ≤ 1, 0.001 ≤ b ≤ 0.1); Li a Mn2G bO4 (wherein 0.90 ≤ a ≤ 1, 0.001 ≤ b ≤ 0.1); QO2; QS2; LiQS2; V2O5; LiV2O5; LiI'O2; LiNiVO4; Li (3-f) J2(PO4)3(0 ≤ f ≤ 2); Li (3-f) A compound represented by any one of the chemical formulas Fe2(PO4)3(0 ≤ f ≤ 2); LiFePO4 can be used.

[0115] In the chemical formula representing the above-described compound, A is Ni, Co, Mn, or a combination thereof; B' is Al, Ni, Co, Mn, Cr, Fe, Mg, Sr, V, a rare earth element, or a combination thereof; D is O, F, S, P, or a combination thereof; E is Co, Mn, or a combination thereof; F' is F, S, P, or a combination thereof; G is Al, Cr, Mn, Fe, Mg, La, Ce, Sr, V, or a combination thereof; Q is Ti, Mo, Mn, or a combination thereof; I' is Cr, V, Fe, Sc, Y, or a combination thereof; J is V, Cr, Mn, Co, Ni, Cu, or a combination thereof. It is also possible to use a compound having a coating layer added to the surface of the above-described compound, or it is also possible to use a mixture of the above-described compound and the compound having a coating layer added. The coating layer added to the surface of the above-mentioned compound includes a coating element compound of, for example, an oxide, a hydroxide, an oxyhydroxide of the coating element, an oxycarbonate of the coating element, or a hydroxycarbonate of the coating element of the coating element. The compound forming the coating layer is amorphous or crystalline. The coating elements included in the coating layer are Mg, Al, Co, K, Na, Ca, Si, Ti, V, Sn, Ge, Ga, B, As, Zr, or a mixture thereof. The method for forming the coating layer is selected within a range that does not adversely affect the physical properties of the positive electrode active material. The coating method includes, for example, spray coating and dipping. Since the specific coating method is well understood by those working in the relevant field, a detailed description thereof will be omitted.

[0116] The oxide-based cathode active material may include, for example, a lithium transition metal oxide represented by the following chemical formulas 11 to 18:

[0117] <Chemical Formula 11>

[0118] Li a Ni x Co y M zO 2-b A b

[0119] In the above chemical formula 11,

[0120] 1.0≤a≤1.2, 0≤b≤0.2, 0.8≤x<1, 0≤y≤0.3, 0 <z≤0.3, 및 x+y+z=1이고,

[0121] M is manganese (Mn), niobium (Nb), vanadium (V), magnesium (Mg), gallium (Ga), silicon (Si), tungsten (W), molybdenum (Mo), iron (Fe), chromium (Cr), copper (Cu), zinc (Zn), titanium (Ti), aluminum (Al), boron (B), or a combination thereof,

[0122] A is F, S, Cl, Br or a combination thereof,

[0123] <Chemical Formula 12>

[0124] LiNi x Co y Mn z O2

[0125] <Chemical Formula 13>

[0126] LiNi x Co y Al z O2

[0127] In the above chemical formulas 12 to 13, 0.8≤x≤0.95, 0≤y≤0.2, 0 <z≤0.2 및 x+y+z=1이며,

[0128] <Chemical Formula 14>

[0129] LiNi x Co y Mn z Al w O2

[0130] In the above chemical formula 14, 0.8≤x≤0.95, 0≤y≤0.2, 0 <z≤0.2, 0<w≤0.2, 및 x+y+z+w=1이며,

[0131] <Chemical Formula 15>

[0132] Li a Co x M y O2-b A b

[0133] In the above chemical formula 15,

[0134] 1.0≤a≤1.2, 0≤b≤0.2, 0.9≤x≤1, 0≤y≤0.1, and x+y=1,

[0135] M is manganese (Mn), niobium (Nb), vanadium (V), magnesium (Mg), gallium (Ga), silicon (Si), tungsten (W), molybdenum (Mo), iron (Fe), chromium (Cr), copper (Cu), zinc (Zn), titanium (Ti), aluminum (Al), boron (B), or a combination thereof,

[0136] A is F, S, Cl, Br or a combination thereof,

[0137] <Chemical Formula 16>

[0138] Li a Ni x Mn y M' z O 2-b A b

[0139] In the above chemical formula 16,

[0140] 1.0≤a≤1.2, 0≤b≤0.2, 0 <x≤0.3, 0.5≤y<1, 0<z≤0.3, 및 x+y+z=1이고,

[0141] M' is cobalt (Co), niobium (Nb), vanadium (V), magnesium (Mg), gallium (Ga), silicon (Si), tungsten (W), molybdenum (Mo), iron (Fe), chromium (Cr), copper (Cu), zinc (Zn), titanium (Ti), aluminum (Al), boron (B) or a combination thereof,

[0142] A is F, S, Cl, Br or a combination thereof,

[0143] <Chemical Formula 17>

[0144] Li a M1 x M2 y PO 4-b X b

[0145] In the above chemical formula 17, 0.90≤a≤1.1, 0≤x≤0.9, 0≤y≤0.5, 0.9 <x+y<1.1, 0≤b≤2이며,

[0146] M1 is chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), zirconium (Zr) or a combination thereof,

[0147] M2 is magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), titanium (Ti), zinc (Zn), boron (B), niobium (Nb), gallium (Ga), indium (In), molybdenum (Mo), tungsten (W), aluminum (Al), silicon (Si), chromium (Cr), vanadium (V), scandium (Sc), yttrium (Y) or a combination thereof, and X is O, F, S, P or a combination thereof.

[0148] <Chemical Formula 18>

[0149] Li a M3 z PO4

[0150] In the above chemical formula 18, 0.90≤a≤1.1, 0.9≤z≤1.1,

[0151] M3 is chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), zirconium (Zr), or a combination thereof.

[0152] The content of the positive electrode active material included in the positive electrode active material layer (12) may be 80 wt% to 99 wt%, 90 wt% to 99 wt%, or 95 wt% to 99 wt% of the total weight of the positive electrode active material layer (12).

[0153] The cathode active material layer (12) may further include a conductive material. Examples of the conductive material include, but are not limited to, carbon black, graphite particles, natural graphite, artificial graphite, acetylene black, Ketjen black, carbon fibers; carbon nanotubes; metal powders or metal fibers or metal tubes such as copper, nickel, aluminum, and silver; and conductive polymers such as polyphenylene derivatives. Any conductive material used in the art may be used. Alternatively, the cathode may not include a separate conductive material, for example.

[0154] The conductive material content including the positive electrode active material layer (12) may be 0.1 wt% to 10 wt% or 0.1 wt% to 5 wt% of the total weight of the positive electrode active material layer (12).

[0155] The cathode active material layer (12) may further include, for example, a binder. Examples of binders that may be used include vinylidene fluoride / hexafluoropropylene copolymer, polyvinylidene fluoride, polyacrylonitrile, polymethyl methacrylate, polytetrafluoroethylene (PTFE), a mixture of the aforementioned polymers, and a styrene butadiene rubber-based polymer.

[0156] The binder content including the positive electrode active material layer (12) may be 0.1 wt% to 10 wt% or 0.1 wt% to 5 wt% of the total weight of the positive electrode active material layer (12).

[0157] The contents of the cathode active material, conductive agent, and binder contained in the cathode are at levels typically used in lithium batteries. Depending on the intended use and configuration of the lithium battery, one or more of the conductive agent and binder may be omitted.

[0158] [Anode: Anode current collector]

[0159] The material constituting the positive electrode current collector (11) can be any material that does not react with lithium, that is, any material that does not form an alloy or compound with lithium and has conductivity. The positive electrode current collector (11) is, for example, a metal or an alloy. The positive electrode current collector (11) can be made of, for example, aluminum (Al), indium (In), copper (Cu), magnesium (Mg), stainless steel, titanium (Ti), iron (Fe), cobalt (Co), nickel (Ni), zinc (Zn), germanium (Ge) or an alloy thereof. The positive electrode current collector (11) can have a shape selected from, for example, a sheet, a foil, a film, a plate, a porous body, a mesoporous body, a body containing through-holes, a polygonal ring body, a mesh body, a foam body, and a non-woven body, but is not necessarily limited to these shapes, and any shape used in the relevant technical field can be used.

[0160] Alternatively, the cathode current collector (11) may include, for example, a base film and a metal layer disposed on one or both sides of the base film. The base film may include, for example, a polymer. The polymer may be, for example, a thermoplastic polymer. The polymer may include, for example, polyethylene terephthalate (PET), polyethylene (PE), polypropylene (PP), polybutylene terephthalate (PBT), polyimide (PI), or a combination thereof. The polymer may be an insulating polymer. Since the base film includes an insulating thermoplastic polymer, when a short circuit occurs, the base film may soften or liquefy, thereby blocking battery operation and suppressing a sudden increase in current. The metal layer may include, for example, aluminum (Al), indium (In), copper (Cu), magnesium (Mg), stainless steel, titanium (Ti), iron (Fe), cobalt (Co), nickel (Ni), zinc (Zn), germanium (Ge), or an alloy thereof. The positive electrode current collector (11) may additionally include a metal piece and / or a lead tab. For more specific details regarding the base film, metal layer, metal chip, and lead tab of the positive electrode current collector (11), refer to the negative electrode current collector (21) described above. By having such a structure, the positive electrode current collector (11) can reduce the weight of the positive electrode, thereby improving the energy density of the positive electrode and the lithium battery.

[0161] [Electrolyte layer]

[0162] [Electrolyte layer: electrolyte]

[0163] The electrolyte layer (30) contains an electrolyte.

[0164] The electrolyte may be, for example, a liquid electrolyte, a solid electrolyte, a gel electrolyte, or a combination thereof.

[0165] Liquid electrolytes are, for example, organic electrolytes. Organic electrolytes are manufactured by dissolving lithium salts in organic solvents.

[0166] Any organic solvent used in the relevant technical field may be used. Examples of the organic solvent include propylene carbonate, ethylene carbonate, fluoroethylene carbonate, butylene carbonate, dimethyl carbonate, diethyl carbonate, methyl ethyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, methyl isopropyl carbonate, dipropyl carbonate, dibutyl carbonate, benzonitrile, acetonitrile, tetrahydrofuran, 2-methyltetrahydrofuran, γ-butyrolactone, dioxolane, 4-methyldioxolane, N,N-dimethylformamide, dimethylacetamide, dimethyl sulfoxide, dioxane, 1,2-dimethoxyethane, sulfolane, dichloroethane, chlorobenzene, nitrobenzene, diethylene glycol, dimethyl ether, or mixtures thereof.

[0167] Lithium salts are all possible if they are used as lithium salts in the relevant technical field. Lithium salts include, for example, LiPF6, LiBF4, LiSbF6, LiAsF6, LiClO4, LiCF3SO3, Li(CF3SO2)2N, LiC4F9SO3, LiAlO2, LiAlCl4, LiDFOB, LiN(C x F 2x+1 SO2)(C y F 2y+1 SO2)(1≤x≤20, 1≤y≤20), LiCl, LiI or a mixture thereof. The concentration of the lithium salt is, for example, 0.1 M to 5.0 M.

[0168] The solid electrolyte is, for example, an oxide-based solid electrolyte, a sulfide-based solid electrolyte, a polymer solid electrolyte, or a combination thereof.

[0169] Solid electrolytes are, for example, oxide-based solid electrolytes. Oxide-based solid electrolytes are Li 1+x+y Al x Ti 2-x Si y P 3-y O 12 (0 <x<2, 0혏<3), BaTiO3, Pb(Zr,Ti)O3(PZT), Pb 1-x La x Zr1-y Ti y O3(PLZT)(O≤x<1, O≤y<1), PB(Mg3Nb 2 / 3 )O3-PbTiO3(PMN-PT), HfO2, SrTiO3, SnO2, CeO2, Na2O, MgO, NiO, CaO, BaO, ZnO, ZrO2, Y2O3, Al2O3, TiO2, SiO2, Li3PO4, Li x Ti y (PO4)3(0 <x<2, 0<y<3), Li x Al y Ti z (PO4)3(0 <x<2, 0<y<1, 0<z<3), Li 1+x+y (Al, Ga) x (Ti, Ge) 2-x Si y P 3-y O 12 (0≤x≤1 0≤y≤1), Li x La y TiO3(0 <x<2, 0<y<3), Li2O, LiOH, Li2CO3, LiAlO2, Li2O-Al2O3-SiO2-P2O5-TiO2-GeO2, Li 3+x La3M2O 12 (M = Te, Nb, or Zr, x is an integer from 1 to 10) is one or more selected from. The solid electrolyte is manufactured by a sintering method, etc. An oxide-based solid electrolyte is, for example, Li7La3Zr2O 12 (LLZO) and Li 3+x La3Zr 2-a M a O 12 A garnet-type solid electrolyte selected from (M doped LLZO, M=Ga, W, Nb, Ta, or Al, x is an integer from 1 to 10).

[0170] The sulfide-based solid electrolyte may include, for example, lithium sulfide, silicon sulfide, phosphorus sulfide, boron sulfide, or a combination thereof. The sulfide-based solid electrolyte particles may include Li2S, P2S5, SiS2, GeS2, B2S3, or a combination thereof. The sulfide-based solid electrolyte particles may be Li2S or P2S5. Sulfide-based solid electrolyte particles are known to have high lithium ion conductivity compared to other inorganic compounds. For example, the sulfide-based solid electrolyte includes Li2S and P2S5. When the sulfide solid electrolyte material constituting the sulfide-based solid electrolyte includes Li2S-P2S5, the mixing molar ratio of Li2S to P2S5 may be, for example, in a range of about 50:50 to about 90:10. In addition, Li3PO4, halogen, halogen compound, Li 2+2x Zn 1-x GeO4("LISICON", 0≤x<1), Li 3+y PO 4-x N x( "LIPON", 0 <x<4, 0<y<3), Li 3.25 Ge 0.25 P 0.75 S4("ThioLISICON"), Li2O-Al2O3-TiO2-P2O 5( An inorganic solid electrolyte prepared by adding "LATP") etc. to an inorganic solid electrolyte of Li2S-P2S5, SiS2, GeS2, B2S3, or a combination thereof can be used as a sulfide solid electrolyte. Non-limiting examples of sulfide solid electrolyte materials include Li2S-P2S5; Li2S-P2S5-LiX (X=halogen element); Li2S-P2S5-Li2O; Li2S-P2S5-Li2O-LiI; Li2S-SiS2; Li2S-SiS2-LiI; Li2S-SiS2-LiBr; Li2S-SiS2-LiCl; Li2S-SiS2-B2S3-LiI; Li2S-SiS2-P2S5-LiI; Li2S-B2S3; Li2S -P2S5-Z m S n(0 <m<10, 0<n<10, Z=Ge, Zn 또는 Ga); Li2S-GeS2; Li2S-SiS2-Li3PO4; 및 Li2S-SiS2-Li p MO q (0 <p<10, 0<q<10, M=P, Si, Ge, B, Al, Ga 또는 In)을 포함한다. 이와 관련하여, 황화물계 고체전해질 재료는 황화물계 고체전해질 물질의 원료 시작 물질(예를 들면, Li2S, P2S5, 등)을 용융 담금질법(melt quenching method), 기계적 밀링법 등에 의해 처리함으로써 제조될 수 있다. 또한, 소성(calcinations) 공정이 상기 처리 후에 수행될 수 있다. 황화물계 고체전해질은 비정질이거나, 결정질이거나, 이들이 혼합된 상태일 수 있다.

[0171] The sulfide-based solid electrolyte may include, for example, an argyrodite type solid electrolyte represented by the following chemical formula 19:

[0172] <Chemical Formula 19>

[0173] Li + 12-n-x A n+ X 2- 6-x Y - x

[0174] In the above formula, A is P, As, Ge, Ga, Sb, Si, Sn, Al, In, Ti, V, Nb or Ta, X is S, Se or Te, Y is Cl, Br, I, F, CN, OCN, SCN or N3, and 1≤n≤5, 0≤x≤2. The sulfide-based solid electrolyte is, for example, Li 7-x PS 6-x Cl x , 0≤x≤2, Li 7-x PS 6-x Br x , 0≤x≤2, and Li 7-x PS 6-x I x, may be an argyrodite-type compound including at least one selected from 0≤x≤2. The sulfide-based solid electrolyte may be, for example, an argyrodite-type compound including at least one selected from Li6PS5Cl, Li6PS5Br, and Li6PS5I.

[0175] The density of the argyrodite-type solid electrolyte may be 0.1 to 2.0 g / cc, 0.5 to 2.0 g / cc, 1.0 to 2.0 g / cc, or 1.5 to 2.0 g / cc. Since the argyrodite-type solid electrolyte has a density in this range, the internal resistance of the solid secondary battery (1) is reduced, and penetration of the solid electrolyte layer by Li can be effectively suppressed.

[0176] The polymer solid electrolyte may, for example, comprise a mixture of a lithium salt and a polymer, or a polymer having an ion-conducting functional group. The polymer solid electrolyte may be, for example, a polymer electrolyte that is solid at 25°C and 1 atm. The polymer solid electrolyte may not, for example, comprise a liquid.The polymer solid electrolyte comprises a polymer, and the polymer is, for example, polyethylene oxide (PEO), polyvinylidene fluoride (PVDF), vinylidene fluoride-hexafluoropropylene (PVDF-HFP), polyethylene oxide (PEO), poly(styrene-b-ethylene oxide) block copolymer (PS-PEO), poly(styrene-butadiene), poly(styrene-isoprene-styrene), poly(styrene-b-divinylbenzene) block copolymer, poly(styrene-ethylene oxide-styrene) block copolymer, polystyrene sulfonate (PSS), polyvinyl fluoride (PVF), polymethyl methacrylate (PMMA, poly(methylmethacrylate), polyethylene glycol (PEG), polyacrylonitrile (PAN), polytetrafluoroethylene (PTFE), polyethylenedioxythiophene (PEDOT), polypyrrole (PPY), Polyacrylonitrile (PAN), polyaniline, polyacetylene, Nafion, Aquivion, Flemion, Gore, Aciplex, Morgane ADP, sulfonated poly(ether ether ketone) (SPEEK), sulfonated poly(arylene ether ketone ketone sulfone) (SPAEKKS), sulfonated poly(aryl ether ketone) (SPAEK), poly[bis(benzimidazobenzisoquinolinones)] (SPBIBI), poly(styrene sulfonate) (PSS), lithium 9,10-Diphenylanthracene-2-sulfonate (lithium 9,10-diphenylanthracene-2-sulfonate, DPASLi. +) or a combination thereof, but is not limited thereto, and any lithium salt that can be used in polymer electrolytes in the relevant technical field is possible. The lithium salt can be any lithium salt that can be used in the relevant technical field. The lithium salt is, for example, LiPF6, LiBF4, LiSbF6, LiAsF6, LiClO4, LiCF3SO3, Li(CF3SO2)2N, LiC4F9SO3, LiAlO2, LiAlCl4, LiN(C x F 2x+1 SO2)(C y F 2y+1 SO2) (x and y are each 1 to 20), LiCl, LiI or a mixture thereof, etc. The polymer included in the polymer solid electrolyte may be, for example, a compound including 10 or more, 20 or more, 50 or more or 100 or more repeating units. The weight average molecular weight of the polymer included in the polymer solid electrolyte may be, for example, 1000 Dalton or more, 10,000 Dalton or more, 100,000 Dalton or more or 1,000,000 Dalton or more.

[0177] A gel electrolyte is, for example, a polymer gel electrolyte. A gel electrolyte can have a gel state without containing a polymer, for example.

[0178] A polymer gel electrolyte may include, for example, a liquid electrolyte and a polymer, or an organic solvent and a polymer having an ion-conducting functional group. The polymer gel electrolyte may be, for example, a polymer electrolyte that is in a gel state at 25°C and 1 atm. The polymer gel electrolyte may, for example, have a gel state without containing a liquid. The liquid electrolyte used in the polymer gel electrolyte may be, for example, a mixture of an ionic liquid, a lithium salt, and an organic solvent; a mixture of a lithium salt and an organic solvent; a mixture of an ionic liquid and an organic solvent; or a mixture of a lithium salt and an ionic liquid. The polymer used in the polymer gel electrolyte may be selected from among the polymers used in solid polymer electrolytes. The organic solvent may be selected from among the organic solvents used in liquid electrolytes. The lithium salt may be selected from among the lithium salts used in solid polymer electrolytes. An ionic liquid refers to a salt that has a melting point below room temperature, is composed solely of ions, and is liquid at room temperature or a molten salt at room temperature. The ionic liquid may include, for example, one or more cations selected from among a) ammonium compounds, pyrrolidinium compounds, pyridinium compounds, pyrimidinium compounds, imidazolium compounds, piperidinium compounds, pyrazolium compounds, oxazolium compounds, pyridazinium compounds, phosphonium compounds, sulfonium compounds, triazolium compounds, and mixtures thereof, and b) one or more anions selected from among BF4-, PF6-, AsF6-, SbF6-, AlCl4-, HSO4-, ClO4-, CH3SO3-, CF3CO2-, Cl-, Br-, I-, BF4-, SO4-, CF3SO3-, (FSO2)2N-, (C2F5SO2)2N-, (C2F5SO2)(CF3SO2)N-, and (CF3SO2)2N-. A polymer solid electrolyte can form a polymer gel electrolyte, for example, by being impregnated into a liquid electrolyte in a secondary battery. The polymer gel electrolyte may further include inorganic particles. The polymer included in the polymer gel electrolyte may be, for example, a compound containing 10 or more, 20 or more, 50 or more, or 100 or more repeating units.The weight average molecular weight of the polymer included in the polymer gel electrolyte may be, for example, 500 Dalton or more, 1000 Dalton or more, 10,000 Dalton or more, 100,000 Dalton or more, or 1,000,000 Dalton or more.

[0179] The polymer gel electrolyte may include, for example, a crosslinking product of a crosslinking monomer and a liquid electrolyte. The polymer gel electrolyte may be obtained, for example, by heat treating a precursor composition including a crosslinking monomer and a liquid electrolyte.

[0180] The crosslinking monomer may comprise, for example, 3 to 20, 3 to 10, 3 to 8, or 4 to 6 reactive functional groups. The crosslinking monomer may comprise, for example, an acrylic monomer comprising a plurality of acrylic groups, a methacrylic monomer comprising a plurality of methacrylic groups, or a combination thereof. Acrylic monomers include, for example, trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, trimethylolpropane ethoxylate triacrylate, trimethylolpropane propoxylate triacrylate, ditrimethylolpropane tetraacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, pentaerythritol ethoxylate tetraacrylate, dipentaerythritol pentaacrylate, It may contain dipentaerythritol hexaacrylate or a combination thereof.

[0181] The liquid electrolyte can be selected from the liquid electrolytes described above.

[0182] [Electrolyte layer: porous substrate]

[0183] The electrolyte layer (30) may further include a porous substrate in addition to the electrolyte.

[0184] The porous substrate may be, for example, a porous membrane. The porous membrane may be, for example, a microporous membrane. The porous membrane may be, for example, a woven fabric or a non-woven fabric. The porous membrane may be any material commonly used in lithium batteries. The porous membrane may include, for example, glass fiber, an olefin-based resin, a fluoropolymer, an ester-based resin, an imide-based resin, an acrylic resin, a cellulose-based resin, or a combination thereof. The olefin-based resin may include, for example, polyethylene, polypropylene, or a combination thereof. The fluoropolymer-based resin may include, for example, polyvinylidene fluoride, polytetrafluoroethylene, or a combination thereof. The ester-based resin may include, for example, polyethylene terephthalate, polybutylene terephthalate, or a combination thereof. The imide-based resin may include, for example, polyamideimide, polyetherimide, or a combination thereof. The acrylic resin may include, for example, polyacrylonitrile, polyacrylate, or a combination thereof. The cellulosic resin may include, for example, carboxymethylcellulose, microbial cellulose, plant cellulose, animal cellulose, or a combination thereof. The porous substrate may be, for example, a separator.

[0185] The porous substrate is manufactured by the following exemplary methods, but is not limited to these methods and may be adjusted according to required conditions.

[0186] First, a porous membrane-forming composition is prepared by mixing a polymer resin, a filler, and a solvent. The porous membrane can be formed, for example, by directly coating the porous membrane-forming composition on the top of an electrode and drying it. Alternatively, the porous membrane-forming composition can be cast on a support and dried, and then the porous membrane peeled from the support and laminated on the top of an electrode to form a porous membrane. The polymer used in the preparation of the porous membrane is not particularly limited, and the resins described above can be used. Any polymer used as a binder for an electrode can be used. The polymer used in the preparation of the porous membrane can include, for example, a vinylidene fluoride / hexafluoropropylene copolymer, polyvinylidene fluoride (PVDF), polyacrylonitrile, polymethyl methacrylate, or a combination thereof.

[0187] [cathode]

[0188] Referring to FIGS. 9 and 10, a lithium battery (1) according to one embodiment includes a negative electrode (20), and the negative electrode (20) includes a negative electrode current collector (21), an electrodeposition-inducing layer (22) disposed on the negative electrode current collector (21), and a negative electrode active material layer (23).

[0189] The negative electrode current collector (21), electrodeposition induction layer (22), and negative electrode active material layer (23) refer to the negative electrode described above.

[0190] [Cathode manufacturing method]

[0191] A method for manufacturing a negative electrode according to one embodiment includes the steps of: providing a negative electrode collector; providing the negative electrode collector to a spin coater; coating a solution containing a conductive polymer on the negative electrode collector provided to the spin coater to provide a second electrodeposition-inducing layer containing a conductive polymer on the negative electrode collector; and immersing the negative electrode collector on which the second electrodeposition-inducing layer is formed in a solution containing a metal to provide a first electrodeposition-inducing layer on the second electrodeposition-inducing layer.

[0192] First, a negative electrode current collector is provided. The negative electrode current collector may be copper foil. For details on the negative electrode current collector, refer to the negative electrode described above.

[0193] Next, the negative electrode collector is provided to a spin coater. By providing the negative electrode collector to the spin coater, the negative electrode collector can be rotated later.

[0194] The rotation speed of the spin coater may be, for example, 3000 rpm or less, 2500 rpm or less, 2000 rpm or less, 1500 rpm or less, 1000 rpm or less, 800 rpm or less, or 500 rpm or less.

[0195] The rotation speed of the spin coater can be, for example, 500 rpm to 3000 rpm, 800 rpm to 2500 rpm, 1000 rpm to 2000 rpm, or 1500 rpm to 2000 rpm.

[0196] Next, a solution containing a conductive polymer is coated on the negative electrode current collector to provide a second electrodeposition-inducing layer containing a conductive polymer on the negative electrode current collector. The negative electrode current collector provided to the spin coater may be rotated while spray-coating the solution containing the conductive polymer.

[0197] Therefore, the rotation speed of the spin coater may be, for example, 3000 rpm or less, 2500 rpm or less, 2000 rpm or less, 1500 rpm or less, 1000 rpm or less, 800 rpm or less, or 500 rpm or less, as described above.

[0198] The rotation speed of the spin coater can be, for example, 500 rpm to 3000 rpm, 800 rpm to 2500 rpm, 1000 rpm to 2000 rpm, or 1500 rpm to 2000 rpm.

[0199] The rotation time of the spin coater may be, for example, 1 second or more and 200 seconds or less, 5 seconds or more and 150 seconds or less, 10 seconds or more and 100 seconds or less, or 10 seconds or more and 90 seconds or less.

[0200] A solution containing a conductive polymer can be sprayed from a spray, which may be referred to as spray coating.

[0201] The spray comprises a nozzle, the nozzle being 0.2 to 0.5 mm.

[0202] The pressure, i.e. hydraulic pressure, at which the solution containing the conductive polymer is spray-coated can be 1 to 30 psi, 2 to 20 psi, 3 to 15 psi, 4 to 10 psi or 5 to 7 psi.

[0203] In a solution containing a conductive polymer, the content of the conductive polymer may be, for example, 30 wt% or less, 25 wt% or less, 20 wt% or less, 15 wt% or less, 10 wt% or less, 5 wt% or less, 2 wt% or less, or 1 wt% or less.

[0204] In a solution containing a conductive polymer, the content of the conductive polymer may be, for example, 1 wt % or more and 30 wt % or less, 1 wt % or more and 25 wt % or less, 1 wt % or more and 20 wt % or less, or 1 wt % or more and 15 wt % or less.

[0205] A solution containing a conductive polymer is, for example, a solution containing an organic solvent, a conductive polymer, and an anionic dopant.

[0206] The type of organic solvent is not particularly limited, and any solvent used in the relevant technical field that can dissolve a conductive polymer, for example, poly(3,4-ethylenedioxythiophene)-block-poly(ethylene glycol), may be used. Examples of the organic solvent include nitromethane, dimethyl anethimide, NMP, etc.

[0207] For more specific details on the conductive polymer, see the description in the electrodeposition induction layer.

[0208] The anionic dopant may be perchlorate, sulfate, toluenesulfonate, polystyrene sulfonate, sodium dodecylbenzenesulfonate, or any combination thereof.

[0209] Next, the negative electrode current collector having a second electrodeposition-inducing layer including a conductive polymer formed thereon is immersed in a solution containing a metal. By immersing the negative electrode current collector having a second electrodeposition-inducing layer including a conductive polymer formed thereon in a solution containing a metal, a first electrodeposition-inducing layer is formed.

[0210] A solution containing a metal is, for example, an aqueous solution containing a nitrate containing a metal.

[0211] The content of nitrate in the solution containing the metal may be, for example, 10 mM or less, 5 mM or less, 2 mM or less, or 1 mM or less.

[0212] The content of nitrate in the solution containing the metal may be, for example, 0.1 mM to 10 mM, 0.5 mM to 5 mM, 0.8 mM to 2 mM, or 0.8 mM to 1 mM.

[0213] The nitrate may be, for example, silver nitrate, gold nitrate, platinum nitrate, palladium nitrate, aluminum nitrate, bismuth nitrate, tin nitrate, zinc nitrate, or any combination thereof, as described in the electrodeposition-inducing layer. For example, when the nitrate is silver nitrate, the silver nitrate may be reduced to cause silver (Ag) particles to be distributed on the second electrodeposition-inducing layer, thereby forming a first electrodeposition-inducing layer comprising silver.

[0214] [Lithium Battery Manufacturing Method]

[0215] A method for manufacturing a lithium battery according to one embodiment includes a step of preparing an assembly by laminating a negative electrode, a porous film, and a positive electrode; and a step of preparing a lithium battery by injecting an electrolyte into the assembly and sealing it.

[0216] A positive electrode is prepared. For example, a positive electrode active material composition is prepared by mixing a positive electrode active material, a conductive agent, a binder, and a solvent. The prepared positive electrode active material composition is directly coated on a positive electrode current collector and dried to produce a positive electrode plate having a positive electrode active material layer formed thereon. Alternatively, the positive electrode active material composition is cast on a separate support, and then the film obtained by peeling from the support is laminated on a positive electrode current collector to produce a positive electrode plate having a positive electrode active material layer formed thereon. The solvent is, for example, N-methylpyrrolidone, but is not particularly limited. It is also possible to form pores inside the electrode plate by further adding a plasticizer or a pore forming agent to the positive electrode active material composition. The positive electrode can be prepared by the methods described above, but is not necessarily limited thereto. The types and contents of the positive electrode active material, conductive agent, and binder refer to the positive electrode active material layer described above.

[0217] Prepare the cathode. For more specific information about the cathode, refer to the cathode section above.

[0218] Prepare a porous membrane. For example, a polyethylene separator is used. For more detailed information about the porous membrane, refer to the electrolyte layer section described above.

[0219] An assembly is prepared by laminating a cathode, a porous membrane, and an anode. The assembly is contained in a can or pouch. The porous membrane refers to the electrolyte layer described above.

[0220] Injecting and sealing the electrolyte into the assembly. By injecting the electrolyte into the assembly contained in a can or pouch, the electrolyte is impregnated into the porous membrane.

[0221] The lithium battery (1) may have a structure as shown in FIGS. 11 to 14 below, for example.

[0222] Referring to FIG. 11, a lithium battery (1) according to an embodiment includes a positive electrode (3), the above-described negative electrode (2), and a separator (4). The positive electrode (3), the negative electrode (2), and the separator (4) are wound or folded to form a battery structure (7). The formed battery structure (7) is accommodated in a battery case (5). A composition for forming a positive electrode electrolyte is injected into the battery case (5), cross-linked, and sealed with a cap assembly (6), thereby completing the lithium battery (1). The battery case (5) is cylindrical, but is not necessarily limited to this shape, and may be, for example, square, thin-film, etc.

[0223] Referring to FIG. 12, a lithium battery (1) according to an embodiment includes a positive electrode (3), the above-described negative electrode (2), and a separator (4). The positive electrode (3), the negative electrode (2), and the separator (4) are wound, folded, or laminated to form a battery structure (7). The formed battery structure (7) is accommodated in a battery case (5). A composition for forming a positive electrode electrolyte is injected into the battery case (5), cross-linked, and sealed to complete the lithium battery (1). The battery case (5) is square, but is not necessarily limited to this shape, and may be, for example, cylindrical, thin-film, etc. A positive electrode lead tab (3') and a positive electrode terminal (3") are electrically connected to the positive electrode (3). A negative electrode lead tab (2') and a negative electrode terminal (2") are electrically connected to the negative electrode (2).

[0224] Referring to FIG. 13, a lithium battery (1) according to one embodiment includes a positive electrode (3), the aforementioned negative electrode (2), and a separator (4). A separator (4) is disposed between the positive electrode (3) and the negative electrode (2), and the positive electrode (3), the negative electrode (2), and the separator (4) are wound or folded to form a battery structure (7). The formed battery structure (7) is accommodated in a battery case (5). An electrode tab (8) that serves as an electrical path for guiding a current formed in the battery structure (7) to the outside may be included. A composition for forming a positive electrode electrolyte is injected into the battery case (5), crosslinked, and sealed, thereby completing the lithium battery (1). The battery case (5) is not necessarily limited to a square shape, but may be, for example, a cylindrical shape, a thin film shape, etc.

[0225] Referring to FIG. 14, a lithium battery (1) according to one embodiment includes a positive electrode (3), the aforementioned negative electrode (2), and a separator (4). A separator (4) is disposed between the positive electrode (3) and the negative electrode (2), thereby forming a battery structure. A battery structure (7) is stacked in a bi-cell structure and then accommodated in a battery case (5). An electrode tab (8) serving as an electrical path for guiding a current formed in the battery structure (7) to the outside may be included. A composition for forming a positive electrode electrolyte is injected into the battery case (5), cross-linked, and sealed, thereby completing the lithium metal battery (1). The battery case (5) is not necessarily limited to a square shape, but may be, for example, a cylindrical shape, a thin film shape, etc.

[0226] A pouch-type lithium metal battery uses a pouch as a case for the lithium battery of FIGS. 11 to 14. The pouch-type lithium battery may include one or more battery structures. A separator is disposed between a positive electrode and a negative electrode to form a battery structure. A plurality of battery structures are laminated in the thickness direction, then impregnated with an organic electrolyte, and accommodated and sealed in a pouch to complete the pouch-type lithium metal battery. For example, although not shown in the drawing, the above-described positive electrode, negative electrode, and separator may be simply laminated and accommodated in a pouch in the form of an electrode assembly, or may be wound or folded into a jellyroll-shaped electrode assembly and then accommodated in a pouch. Subsequently, a composition for forming a positive electrode electrolyte is injected into the pouch, and thermal cross-linking and sealing are performed to complete the lithium battery.

[0227] The lithium battery of the present disclosure has excellent lifespan characteristics and high energy density, making it suitable for use in, for example, electric vehicles (EVs). For example, it is used in hybrid vehicles such as plug-in hybrid electric vehicles (PHEVs). It is also used in applications requiring large amounts of power storage, such as electric bicycles and power tools.

[0228] Lithium batteries are stacked in multiple layers to form a battery module, and the multiple battery modules form a battery pack. Such a battery pack can be used in any device requiring high capacity and high output. For example, it can be used in laptops, smartphones, electric vehicles, etc. The battery module includes, for example, multiple batteries and a frame that holds them. The battery pack includes, for example, multiple battery modules and a bus bar that connects them. The battery module and / or the battery pack may further include a cooling device. The multiple battery packs are controlled by a battery management system. The battery management system includes a battery pack and a battery control device connected to the battery pack.

[0229] The present invention is explained in more detail through the following examples and comparative examples. However, the examples are intended to illustrate the present invention and are not intended to limit the scope of the present invention.

[0230] Example 1: Metal-containing first electrodeposition-inducing layer / conductive polymer-containing second electrodeposition-inducing layer cathode

[0231] (Cathode manufacturing)

[0232] A solution containing 1 wt.% poly(3,4-ethylenedioxythiophene)-block-poly(ethylene glycol) (PEDOT-block-PEG) conductive polymer was dispersed in a nitromethane solvent using a spin coater while rotating the copper collector at 2000 rpm, and a second electrodeposition-inducing layer was formed by spraying the solution onto the copper collector at a hydraulic pressure of 5-7 psi. Then, the copper collector on which the second electrodeposition-inducing layer was formed was immersed in a 1 mM silver nitrate (AgNO3) aqueous solution for 3 minutes. + As the ions are reduced by the conductive polymer, a first electrodeposition-induced layer containing Ag particles is formed on the polymer surface.

[0233] (Polar electrode manufacturing)

[0234] LiNi x Co y Al 1-x-y O2(x>88%) powder and carbon conductive material (Super-P; Timcal Ltd.) were uniformly mixed at a weight ratio of 90:5, and then PVDF (polyvinylidene fluoride) binder solution was added to prepare a positive electrode active material slurry so that the weight ratio of active material:carbon conductive material:binder = 90:5:5.

[0235] The manufactured slurry was coated on a 15 ㎛ thick aluminum substrate using a doctor blade, dried under reduced pressure at 120°C, and rolled using a roll press to form a sheet to manufacture a positive electrode.

[0236] (Manufacturing of coin cells)

[0237] A polypropylene separator (Celgard 3510) was placed between the positive and negative electrodes manufactured above, and an electrolyte was injected to manufacture a coin cell.

[0238] As an electrolyte, a solution containing 1.15 M LiPF6 dissolved in EC (ethylene carbonate) + EMC (ethyl methyl carbonate) + DMC (dimethyl carbonate) (2:4:4 volume ratio) was used.

[0239] Comparative Example 1: Electrodeposition-induced layer cathode containing conductive polymer

[0240] A negative electrode and a coin cell were manufactured in the same manner as in Example 1, except that the step of immersing the copper collector on which the second electrodeposition-inducing layer was formed in a silver nitrate aqueous solution was omitted.

[0241] Comparative Example 2: Cu-based cathode

[0242] A negative electrode and coin cell were manufactured in the same manner as in Example 1, except that only a copper current collector was used without forming an electrodeposition induction layer.

[0243] Comparative Example 3: Conductive polymer-containing electrodeposition-induced layer cathode - spin coating

[0244] A negative electrode and coin cell were manufactured in the same manner as in Example 1, except that a solution containing 1 wt.% of a poly(3,4-ethylenedioxythiophene)-block-poly(ethylene glycol) (PEDOT-block-PEG) conductive polymer dispersed in a nitromethane solvent on a copper current collector was dropped and then rotated at 2000 rpm to form a second electrodeposition-inducing layer.

[0245] Comparative Example 4: Electrodeposition-induced layer cathode containing conductive polymer - spray coating

[0246] A negative electrode and coin cell were manufactured in the same manner as in Example 1, except that a solution containing 1 wt.% of a conductive polymer, poly(3,4-ethylenedioxythiophene)-block-poly(ethylene glycol) (PEDOT-block-PEG), dispersed in a nitromethane solvent on a copper current collector was sprayed at a hydraulic pressure of 5-7 psi to form a second electrodeposition-inducing layer.

[0247] Comparative Example 5: Electrodeposition-inducing layer containing PEDOT:PSS polymer

[0248] When manufacturing a negative electrode, a solution containing 1 wt.% of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) conductive polymer dispersed in a nitromethane solvent was sprayed onto the copper current collector using a spray gun at a hydraulic pressure of 5-7 psi while rotating the copper current collector at 2000 rpm using a spin coater to form a second electrodeposition-inducing layer. Then, the copper current collector on which the second electrodeposition-inducing layer was formed was immersed in a 1 mM silver nitrate (AgNO3) aqueous solution for 3 minutes to form a first electrodeposition-inducing layer containing Ag particles on the surface of the polymer as Ag+ ions are reduced by the conductive polymer, and a negative electrode and a coin cell were manufactured in the same manner as in Example 1, except that the copper current collector was then immersed in a 1 mM silver nitrate (AgNO3) aqueous solution for 3 minutes to form a first electrodeposition-inducing layer containing Ag particles on the surface of the polymer.

[0249] Reference Example 1: Metal-containing first electrodeposition-inducing layer / conductive polymer-containing second electrodeposition-inducing layer cathode - Ag nanoparticle spraying

[0250] When manufacturing a negative electrode, a solution containing 1 wt.% of poly(3,4-ethylenedioxythiophene)-block-poly(ethylene glycol) (PEDOT-block-PEG) conductive polymer dispersed in a nitromethane solvent was sprayed onto the copper current collector using a spray gun at a hydraulic pressure of 5-7 psi to form a second electrodeposition-inducing layer. Then, a first electrodeposition-inducing layer was formed on the copper current collector on which the second electrodeposition-inducing layer was formed, and an negative electrode and a coin cell were manufactured in the same manner as in Example 1, except that the solution containing 1 wt.% of silver nanoparticles dispersed in an aqueous solution was sprayed onto the copper current collector using a spray gun at a hydraulic pressure of 5-7 psi to form a first electrodeposition-inducing layer. The surface of the negative electrode on which the electrodeposition-inducing layer was formed is shown in FIG. 12.

[0251] Referring to Figure 12, it was confirmed that a very small amount of silver particles existed, and therefore, it was confirmed that the second electrodeposition-inducing layer was formed in a very small amount.

[0252] Reference Example 2: Electrodeposition-induced layer cathode containing metal and conductive polymer (PEDOT-block-PEG and Ag mixed together in a solvent phase and then coated)

[0253] A negative electrode and a coin cell were manufactured in the same manner as in Example 1, except that a solution containing 1 wt% of poly(3,4-ethylenedioxythiophene)-block-poly(ethylene glycol) (PEDOT-block-PEG) conductive polymer and silver (Ag) dispersed in a nitromethane solvent was sprayed onto the copper current collector at a hydraulic pressure of 5-7 psi to form the second electrodeposition-inducing layer and the first electrodeposition-inducing layer while rotating the copper current collector at 2000 rpm using a spin coater. The surface of the negative electrode on which the electrodeposition-inducing layer was formed is shown in FIG. 13.

[0254] Referring to Figure 13, it was confirmed that silver particles were agglomerated and existed in a non-uniform manner in the form of large lumps.

[0255] Reference Example 3: Electrodeposition-induced layer cathode containing metal and conductive polymer (PEDOT-block-PEG and silver nitrate (AgNO3) mixed together in a solvent phase and then coated)

[0256] A negative electrode and a coin cell were manufactured in the same manner as in Example 1, except that a solution of 1 wt% poly(3,4-ethylenedioxythiophene)-block-poly(ethylene glycol) (PEDOT-block-PEG) conductive polymer in nitromethane solvent, in which 1 mM silver nitrate (AgNO3) was additionally added, was sprayed onto the copper current collector at a hydraulic pressure of 5-7 psi to form the second electrode-inducing layer and the first electrode-inducing layer while rotating the copper current collector at 2000 rpm using a spin coater. The surface of the negative electrode on which the electrode-inducing layer was formed is shown in FIG. 14.

[0257] Referring to Figure 14, it was confirmed that AgNO3 was not reduced to silver nanoparticles and most of it remained on the surface in the form of a salt.

[0258] Evaluation Example 1: Cross-sectional SEM evaluation

[0259] The cross-sections of the cathodes including the electrodeposition-inducing layers manufactured in Example 1 and Comparative Example 1 were measured using SEM and are shown in FIGS. 5a and 5b.

[0260] Referring to FIGS. 5a and 5b, it was confirmed that, unlike Comparative Example 1, a first electrodeposition-inducing layer including Ag was formed in Example 1.

[0261] Evaluation Example 2: XRD Evaluation

[0262] The cathode including the electrodeposition-inducing layer manufactured in Example 1 and Comparative Example 1 was confirmed by XRD and is shown in Fig. 6.

[0263] Unlike Comparative Example 1, it was confirmed that a first electrodeposition-inducing layer including Ag was formed in Example 1.

[0264] Evaluation Example 3: 1 st Charge / discharge curve evaluation

[0265] The lithium battery manufactured in Example 1 was charged at a constant current of 0.1 C rate at 25°C until the voltage reached 4.3 V (vs. Li), and then cut-off at a current of 0.05 C rate while maintaining 4.3 V in constant voltage mode. Subsequently, the battery was discharged at a constant current of 0.1 C rate until the voltage reached 3.6 V (vs. Li) during discharge (formation). In cycling, the battery was charged at a constant current of 0.2 C rate until the voltage reached 4.3 V (vs. Li), and then cut-off at a current of 0.05 C rate while maintaining 4.3 V in constant voltage mode. Subsequently, the battery was discharged at a constant current of 0.5 C rate until the voltage reached 3.6 V (vs. Li).

[0266] This cycle is 200 th The cycle was repeated under the same conditions. The charge / discharge curve is shown in Fig. 7.

[0267] Evaluation Example 4: Charge / Discharge Test

[0268] The lithium batteries manufactured in Example 1, Comparative Example 1, and Comparative Example 2 were charged at a constant current of 0.1 C rate at 25°C until the voltage reached 4.3 V (vs. Li), and then cut-off at a current of 0.05 C rate while maintaining 4.3 V in constant voltage mode. Then, the batteries were discharged at a constant current of 0.1 C rate until the voltage reached 3.6 V (vs. Li) during discharge (formation).

[0269] In the cycle, the battery was charged at a constant current of 0.2 C rate until the voltage reached 4.3 V (vs. Li), and then cut-off at a current of 0.05 C rate while maintaining 4.3 V in constant voltage mode. Subsequently, the battery was discharged at a constant current of 0.5 C rate until the voltage reached 3.6 V (vs. Li).

[0270] This cycle is 200 th The cycle was repeated under the same conditions.

[0271] In all charge / discharge cycles, a 10-minute pause was observed after each charge / discharge cycle. Some of the results of the room-temperature charge / discharge experiments are shown in Table 1 and Fig. 8. The capacity retention rate is defined by the following mathematical equation (1).

[0272] <Mathematical Formula 1>

[0273] Capacity retention rate [%] = [200 th Discharge capacity in cycles / 1 st Discharge capacity in cycles] Х 100

[0274] First electrodeposition-induced layer / Second electrodeposition-induced layer composition capacity retention rate [%] Example 1 Ag / PEDOT-block-PEG 6 2.8 Comparative Example 1 - / PEDOT-block-PEG 5 0.2 Comparative Example 2 - 5 0.7 Comparative Example 3 - / PEDOT-block-PEG 4 3.2 Comparative Example 4 - / PEDOT-block-PEG 4 9.8 Comparative Example 5 Ag / PEDOT:PSS 4 8.4 Reference Example 1 Ag / PEDOT-block-PEG 5 3.3 Reference Example 2 Ag / PEDOT-block-PEG 5 6.1 Reference Example 3 Ag / PEDOT-block-PEG 5 0.7

[0275] As shown in Table 1 and FIG. 8, the lithium battery of Example 1 had improved capacity retention compared to the lithium batteries of Comparative Examples 1 to 5 and Reference Examples 1 to 3.

[0276] This improved capacity retention was determined to be because the first electrodeposition-inducing layer including a conductive polymer and the second electrodeposition-inducing layer including a metal suppressed the formation of lithium dendrites and induced uniform electrodeposition of lithium.

[0277] The lithium battery of Comparative Example 1, which only included the second electrodeposition-inducing layer, exhibited poor life characteristics. This was believed to be because, when only the second electrodeposition-inducing layer was included, the electrodeposition-inducing layer failed to suppress the formation of lithium dendrites and failed to induce uniform electrodeposition of lithium.

[0278] Evaluation Example 5: Confirmation of formation of electrodeposition-induced layer according to coating method

[0279] The coating state of the cathode including the electrodeposition-inducing layer manufactured in Example 1 and Comparative Example 3 or Example 1 and Comparative Example 4 was confirmed, and the results are shown in FIGS. 9 and 10.

[0280] Referring to Fig. 9, it was confirmed that the second electrodeposition-inducing layer formed by Comparative Example 3 was not formed smoothly because the viscosity of the polymer solution was low, and the polymer solution was pushed out of the substrate rather than into it by centrifugal force when the current collector rotated.

[0281] Referring to Fig. 10, it was confirmed that the second electrodeposition-induced layer formed by Comparative Example 4 has lower coating uniformity than spin-spray coating performed under constant conditions because the coating is performed depending on the skill of the experimenter when only spray coating is used.

[0282] Evaluation Example 6: Confirmation of the contact angle of the electrodeposition-inducing layer

[0283] The contact angle of the electrodeposition-inducing layer manufactured in Example 1 and Comparative Example 5 for the electrolyte was confirmed and shown in Fig. 11.

[0284] Referring to Figure 11, the PSS repeating unit has lower affinity for the electrolyte than the PEG repeating unit, and thus, when the liquid electrolyte is dropped, the contact angle is confirmed to be larger, as shown in the figure below. It was confirmed that the low affinity for the electrolyte reduces the wettability of the electrodeposition-inducing layer for the liquid electrolyte, which increases the interfacial resistance when applied to the battery, resulting in deterioration of the cell characteristics.

[0285] While exemplary embodiments have been described in detail with reference to the attached drawings, the present invention is not limited to these examples. It is self-evident that those skilled in the art to which the present invention pertains can devise various modifications or variations within the scope of the technical concepts described in the patent claims, and these also naturally fall within the technical scope of the present invention.

[0286] [Explanation of symbols]

[0287] 1 lithium battery 2, 20 cathode

[0288] 3, 10 positive electrode 4 separator

[0289] 5 Battery case 6 Cap assembly

[0290] 7 Battery structure 8 Electrode tab

[0291] 11. Cathode current collector 12. Cathode active material layer

[0292] 21 Negative current collector 22 Electrodeposition induction layer

[0293] 23 Negative active material layer 30 Solid electrolyte layer

Claims

1. A cathode current collector; and an electrodeposition induction layer disposed on the cathode current collector; The above electrodeposition-inducing layer includes a first electrodeposition-inducing layer and a second electrodeposition-inducing layer disposed between the first electrodeposition-inducing layer and the negative electrode current collector, The above first electrodeposition induction layer includes a metal, A negative electrode for a lithium metal battery, wherein the second electrodeposition-inducing layer comprises a conductive polymer.

2. In the first paragraph, the metal is silver (Ag), gold (Au), platinum (Pt), palladium (Pd), aluminum (Al), bismuth (Bi), tin (Sn), zinc (Zn), or any combination thereof, a negative electrode for a lithium metal battery.

3. A negative electrode for a lithium metal battery, wherein the first electrodeposition-inducing layer further comprises nitrate.

4. In the third paragraph, the nitrate is silver nitrate, gold nitrate, platinum nitrate, palladium nitrate, aluminum nitrate, bismuth nitrate, tin nitrate, zinc nitrate, or any combination thereof, a negative electrode for a lithium metal battery.

5. A negative electrode for a lithium metal battery, wherein the metal in the first paragraph is in the form of particles and is uniformly or non-homogeneously distributed on the second electrodeposition-inducing layer.

6. A negative electrode for a lithium metal battery, wherein the conductive polymer in the first paragraph is a polymer including an electron-conductive repeating unit, a polymer including an ion-conductive repeating unit, a polymer including an electron-conductive repeating unit and an ion-conductive repeating unit, or any combination thereof.

7. A negative electrode for a lithium metal battery, wherein the polymer including the electron-conductive repeating unit in the sixth paragraph is poly(3,4-ethylenedioxythiophene), polyaniline, polypyrrole, polyacetylene, polydopamine, or any combination thereof.

8. A negative electrode for a lithium metal battery, wherein the polymer including the ion-conducting repeating unit in the sixth paragraph is polyethylene glycol, polypropylene oxide, polyimide, polyamine, polynitrile, or any combination thereof.

9. In the sixth paragraph, the polymer including the electron-conductive repeating unit and the ion-conductive repeating unit is a copolymer of a polymer including the electron-conductive repeating unit and a polymer including the ion-conductive repeating unit, wherein the negative electrode for a lithium metal battery.

10. A negative electrode for a lithium metal battery, wherein the copolymer comprises a block copolymer, and the block copolymer comprises i) one or more polymers selected from poly(3,4-ethylenedioxythiophene), polyaniline, polypyrrole, polyacetylene, and polydopamine, and ii) one or more polymers selected from polyethylene glycol, polypropylene oxide, polyimide, polyamine, and polynitrile.

11. A negative electrode for a lithium metal battery, wherein the metal particles have a particle size of 150 nm to 250 nm in the first paragraph.

12. A negative electrode for a lithium metal battery, wherein the thickness of the second electrodeposition-inducing layer in the first paragraph is 0.1 μm to 25 μm.

13. In the first paragraph, a negative electrode active material layer is included on one side of the second electrodeposition induction layer, The above negative electrode active material layer is a metal layer, and the metal layer includes lithium metal or a lithium alloy, or A negative electrode for a lithium metal battery, wherein the negative electrode active material layer comprises lithium foil, lithium powder, plated lithium, or a combination thereof.

14. In the 13th paragraph, the negative electrode active material layer includes non-fibrous lithium or non-acidic lithium, A negative electrode for a lithium metal battery, wherein the negative electrode active material layer comprises plate-shaped lithium.

15. A negative electrode for a lithium metal battery, wherein the thickness of the negative electrode active material layer in the 13th paragraph is 0.1 ㎛ to 100 ㎛.

16. A positive electrode including a positive electrode current collector; and a positive electrode active material layer on one surface of the positive electrode current collector; A cathode according to any one of claims 1 to 15; and A lithium metal battery comprising an electrolyte layer disposed between the positive electrode and the negative electrode.

17. In the 16th paragraph, the electrolyte is a liquid electrolyte, a solid electrolyte, a gel electrolyte or a combination thereof, and the solid electrolyte includes an oxide-based solid electrolyte, a sulfide-based solid electrolyte, a polymer solid electrolyte or a combination thereof. A lithium metal battery, wherein the gel electrolyte comprises a polymer gel electrolyte.

18. In the 16th paragraph, at least one of the positive electrode current collector and the negative electrode current collector includes a base film and a metal layer disposed on one or both sides of the base film, The above base film comprises a polymer, and the polymer comprises polyethylene terephthalate (PET), polyethylene (PE), polypropylene (PP), polybutylene terephthalate (PBT), polyimide (PI) or a combination thereof, A lithium metal battery, wherein the metal layer comprises indium (In), copper (Cu), magnesium (Mg), stainless steel, titanium (Ti), iron (Fe), cobalt (Co), nickel (Ni), zinc (Zn), aluminum (Al), germanium (Ge), lithium (Li), or an alloy thereof.

19. Step of providing a negative electrode collector; A step of providing a cathode collector to a spin coater; A step of coating a solution containing a conductive polymer on the negative electrode collector provided to the spin coater to provide a second electrodeposition-inducing layer containing a conductive polymer on the negative electrode collector; and A method for manufacturing a negative electrode for a lithium metal battery, comprising the step of immersing a negative electrode current collector on which a second electrodeposition-inducing layer is formed in a solution containing a metal to provide a first electrodeposition-inducing layer on the second electrodeposition-inducing layer.

20. In paragraph 19, The conductive polymer is a polymer comprising an electron-conducting repeating unit, a polymer comprising an ion-conducting repeating unit, a polymer comprising an electron-conducting repeating unit and an ion-conducting repeating unit, or any combination thereof, A method for manufacturing a negative electrode for a lithium metal battery, wherein the solution containing the above metal contains nitrate.

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