Negative electrode for all-solid-state battery comprising pulverized conductive additive and method for manufacturing same

Abstract

Provided are a negative electrode for an all-solid-state battery containing a pulverized conductive additive, and a method for manufacturing the same. The negative electrode contains a conductive additive pulverized using a resonance method.

Description

Technical Field

[0001] The present invention relates to a negative electrode for an all-solid-state battery and a method for manufacturing the same. The negative electrode comprises a conductive additive pulverized by a resonance method. Background Art

[0002] The negative electrode for all-solid-state batteries is a composite material containing a silicon-based negative electrode active material, a sulfide-based solid electrolyte, etc. The sulfide-based solid electrolyte in the negative electrode is responsible for lithium ion conduction. When the content of the sulfide-based solid electrolyte is increased to ensure the lithium ion conduction path, the electron conduction path of the silicon-based negative electrode active material is blocked. Therefore, in order to obtain output characteristics, it is necessary to use a conductive additive.

[0003] However, conductive additives tend to aggregate and separate during the anode manufacturing process, so the improvement in electronic conductivity is negligible compared to the amount added. In addition, conductive additives may hinder the formation of dense anodes, resulting in reduced energy density. Summary of the invention

[0004] Therefore, in order to improve the energy density and output of an all-solid-state battery including an anode including a silicon-based anode active material and a sulfide-based solid electrolyte, an appropriate technology for dispersing a conductive additive is required.

[0005] An object of the present invention is to provide a negative electrode for an all-solid-state battery, the negative electrode comprising a uniformly dispersed conductive additive.

[0006] Another object of the present invention is to provide a negative electrode for an all-solid-state battery in which an electron conduction path is well established.

[0007] The objects of the present invention are not limited to the above objects. The above and other objects of the present invention will become more apparent through the following description and the accompanying embodiments.

[0008] According to an embodiment of the present invention, a negative electrode for an all-solid-state battery is provided. The negative electrode comprises a negative electrode active material. The negative electrode further comprises a solid electrolyte, a pulverized conductive additive and a binder. The negative electrode satisfies 0.1 50 The particle size is expressed in micrometers (μm), and “b” is the porosity of the negative electrode, expressed in percentage (%).

[0009] The negative electrode active material may include a silicon-based negative electrode active material.

[0010] The pulverized conductive additive may include carbon black.

[0011] D of the crushed conductive additive 50 The particle size may be in the range of 1 μm to 20 μm. ​

[0012] The porosity of the negative electrode may be in the range of 0.1% to 70%.

[0013] The D of negative electrode active material 50 The particle size may be in the range of 1 μm to 50 μm.

[0014] Solid electrolyte D 50 The particle size may be in the range of 0.1 μm to 10 μm.

[0015] Solid electrolyte D 50 Particle size (D 1 ) and the D of the negative electrode active material 50 Particle size (D 2 ) ratio (D 1 / D 2 ) can be 1 or lower.

[0016] According to another embodiment of the present invention, a method for manufacturing a negative electrode for an all-solid-state battery is provided. The method includes preparing a starting material by mixing an original conductive additive and a pulverizing medium. The method also includes obtaining a pulverized conductive additive by pulverizing the starting material using a resonance method. The method additionally includes preparing a mixture comprising a pulverized conductive additive, a negative electrode active material, a solid electrolyte, and a binder. The method also includes using the mixture to manufacture a negative electrode.

[0017] The mass of the original conductive additive (M 1 ) and the mass of the crushing medium (M 2 ) ratio (M 1 / M 2 ) can be higher than 0.125 and lower than 8.

[0018] Obtaining the pulverized conductive additive may include applying a resonance frequency higher than 0 Hz and lower than 100 Hz to the starting material.

[0019] Obtaining the pulverized conductive additive may include applying a gravitational acceleration in a range of 20G to 80G to the starting material.

[0020] Obtaining the pulverized conductive additive may include applying gravitational acceleration to the starting material for more than 2 minutes and less than 10 minutes.

[0021] According to an embodiment of the present invention, there is provided a negative electrode for an all-solid-state battery, wherein the negative electrode comprises a uniformly dispersed conductive additive.

[0022] According to an embodiment of the present invention, there is provided a negative electrode for an all-solid-state battery in which an electron conduction path is well established.

[0023] The effects of the present invention are not limited to the above-mentioned effects. It should be understood that the effects of the present invention include all effects that can be derived from the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 An all-solid-state battery according to an embodiment of the present invention is shown;

[0025] Figure 2 shows a negative electrode according to an embodiment of the present invention;

[0026] Figure 3 An example of a pulverization process using a resonance method according to an embodiment of the present invention is shown;

[0027] Figure 4A shows a scanning electron microscope (SEM) analysis of the negative electrode according to Example 1;

[0028] Figure 4B shows an energy dispersive X-ray spectroscopy (EDS) analysis of the negative electrode according to Example 1;

[0029] Figure 5A shows a SEM analysis of the negative electrode according to Comparative Example 3;

[0030] Figure 5B shows an EDS analysis of the negative electrode according to Comparative Example 3;

[0031] Figure 6 shows the charge and discharge characteristics of the all-solid-state batteries according to Examples 1 and 2 and Comparative Examples 1 and 2; and

[0032] Figure 7 The capacity retention rates of the all-solid-state batteries according to Examples 1 and 2 and Comparative Examples 1 and 2 are shown. DETAILED DESCRIPTION

[0033] The above-mentioned purpose and other purposes, features and advantages of the present invention should be easily understood from the embodiments and drawings described below. However, the present invention is not limited to the embodiments described herein and can be implemented in other forms. The embodiments described herein are provided so that the disclosed content is comprehensive and complete, and the spirit of the present invention is fully conveyed to the ordinary technicians in the field to which the present invention belongs. In all the drawings, similar elements are represented by similar reference numerals. In the drawings, for the sake of clarity of the present invention, the size of the structure is larger than the actual size. Terms such as "first", "second" used in this article can be used to describe various components, but components should not be interpreted as being limited to these terms. These terms are only used to distinguish one component from another component. For example, without departing from the scope of the present invention, the first component can be referred to as the second component, and the second component can also be referred to as the first component.

[0034] As used in this article, unless the context clearly indicates otherwise, the singular form "one", "an" and "the / said" are intended to also include plural forms. It should also be understood that the terms "include", "comprise", "have" etc. specify the existence of stated features, regions, entireties, steps, operations, elements and / or components when used in this article. These terms do not exclude the existence or addition of one or more other features, regions, entireties, steps, operations, elements, components and / or their combinations. It should also be understood that when an element such as a layer, film, region or sheet is referred to as "above" another element, the element can be directly above another element, or one or more intermediate elements can be present between them. Similarly, when an element such as a layer, film, region or sheet is referred to as "below" another element, the element can be directly below another element, or one or more intermediate elements can be present between them.

[0035] Unless otherwise stated, all numbers, values ​​and / or expressions used in this article to express the amount of components, reaction conditions, polymer compositions and mixtures should be considered as approximate values ​​including various uncertainties that affect measurement, especially when obtaining these values, and should therefore be understood in all cases as modified by the term "about". In addition, when a numerical range is disclosed in this specification, the range is continuous and includes all values ​​from the minimum value of the range to its maximum value, unless otherwise stated. In addition, when such a range involves integer values, all integers including the minimum value to the maximum value are included unless otherwise stated.

[0036] Figure 1 An all-solid-state battery according to an embodiment of the present invention is shown. The all-solid-state battery may include a negative electrode collector 10. The all-solid-state battery may also include a negative electrode 20 disposed on the negative electrode collector 10. The all-solid-state battery may additionally include a solid electrolyte layer 30 disposed on the negative electrode 20. The all-solid-state battery may further include a positive electrode 40 disposed on the solid electrolyte layer 30. The all-solid-state battery may also include a positive electrode collector 50 disposed on the positive electrode 40.

[0037] The negative electrode current collector 10 may be a conductive substrate having a plate-like form. For example, the negative electrode current collector 10 may have a sheet, a film, or a foil form.

[0038] The thickness of the negative electrode current collector 10 is not particularly limited, but may be, for example, in the range of 1 μm to 500 μm.

[0039] The negative electrode current collector 10 may include copper (Cu), nickel (Ni), stainless steel, or the like.

[0040] Figure 2A negative electrode 20 according to an embodiment of the present invention is shown. The negative electrode 20 may include a negative electrode active material 21, a solid electrolyte 22, a pulverized conductive additive 23, a binder (not shown), etc. The negative electrode 20 may have pores 24, that is, gaps between structures.

[0041] The negative electrode active material 21 may include at least one of a silicon-based negative electrode active material, a carbon-based negative electrode active material, or a combination thereof.

[0042] Silicon-based negative electrode active materials may include silicone (Si), silicon oxide (SiO x )(0<x<2), at least one of Si-containing alloys or combinations thereof. The Si-containing alloy may include an alloy of Si and at least one element selected from alkali metals, alkaline earth metals, Group 13 elements, Group 14 elements, transition metals, rare earth elements or combinations thereof.

[0043] The carbon-based negative electrode active material may be graphite, such as mesocarbon microbeads (MCMB), highly oriented pyrolytic graphite (HOPG), etc., or amorphous carbon, such as hard carbon and soft carbon.

[0044] The negative electrode active material 21 may be a composite of a silicon-based negative electrode active material and a carbon-based negative electrode active material. For example, the surface of the carbon-based negative electrode active material may be coated with a silicon-based negative electrode active material. As another example, the surface of the silicon-based negative electrode active material may be coated with a carbon-based negative electrode active material.

[0045] Negative electrode active material 21 D 50 The particle size can be in the range of 1 μm to 50 μm. 50 The particle size corresponds to the 50% cumulative volume particle size in the volume-based cumulative particle size distribution curve. 50 The method for measuring the particle size is not particularly limited. For example, a sample is dispersed by ultrasonication using a laser diffraction particle size distribution measuring device. Then, the particle size distribution is measured, and a volume-based cumulative particle size distribution curve is obtained. In the above cumulative particle size distribution curve, D 50 The particle size can be considered as the 50% cumulative volume particle size.

[0046] The solid electrolyte 22 may include at least one of an oxide-based solid electrolyte, a sulfide-based solid electrolyte, or a combination thereof. In addition, the solid electrolyte 22 may be crystalline, amorphous, or a combination thereof.

[0047] Examples of oxide-based solid electrolytes may include perovskite-type LLTO (Li 3x La 2 / 3-x TiO 3 ), phosphate-based NASICON-type LATP (Li 1+x Al xTi 2-x (PO 4 ) 3 )wait.

[0048] Examples of sulfide-based solid electrolytes may include Li 2 SP 2 S 5 , Li 2 SP 2 S 5 -LiI, Li 2 SP 2 S 5 -LiCl, Li 2 SP 2 S 5 -LiBr, Li 2 SP 2 S 5 -Li 2 O. Li 2 SP 2 S 5 -Li 2 O-LiI、Li 2 S-SiS 2 , Li 2 S-SiS 2 -LiI, Li 2 S-SiS 2 -LiBr, Li 2 S-SiS 2 -LiCl, Li 2 S-SiS 2 -B 2 S 3 -LiI, Li 2 S-SiS 2 -P 2 S 5 -LiI, Li 2 SB 2 S 3 , Li 2 SP 2 S 5 -Z m S n (wherein m and n are each independently a positive integer, and Z is one of germanium (Ge), zinc (Zn), or gallium (Ga)), Li 2 S-GeS 2 , Li 2 S-SiS 2 -Li 3 PO 4 , Li 2 S-SiS 2 -Lix MO y (wherein x and y are each independently a positive integer, and M is one of phosphorus (P), Si, Ge, boron (B), aluminum (Al), Ga, and indium (In)), Li 10 GeP 2 S 12 etc.

[0049] The solid electrolyte 22 may include a sulfide-based solid electrolyte having a thio-LISICON crystal structure. The sulfide-based solid electrolyte having a thio-LISICON crystal structure may include Li 7-y PS 6-y Ha y (wherein Ha includes chlorine (Cl), bromine (Br), or iodine (I), and 0 < y ≤ 2), Li 7-z PS 6-z (Ha1 1-b Ha2 b ) z (wherein Ha1 and Ha2 are different from each other and each independently includes Cl, Br, or I, 0 < b < 1, and 0 < z ≤ 2), or at least one of combinations thereof.

[0050] The D 50 particle size of the solid electrolyte 22 may be in the range of 0.1 μm to 10 μm.

[0051] The D 50 particle size (D 1 ) of the solid electrolyte 22 and the D 50 particle size (D 2 ) of the negative electrode active material 21 The ratio (D 1 / D 2 ) may be 1 or less. When the ratio (D 1 / D 2 ) is 1 or less, a lithium ion conduction and electron transport path can be easily formed in the negative electrode 20.

[0052] The pulverized conductive additive 23 may refer to the resulting product obtained by pulverizing the original conductive additive using a predetermined method. The pulverized conductive additive 23 (conductive material) may include carbon black. For example, the conductive additive 23 may include Super-p, Super-C65, Denka Black, Ketjen Black, acetylene black, etc.

[0053] The D 50 particle size of the pulverized conductive additive 23 may be in the range of 1 μm to 20 μm. In addition, the negative electrode 20 may satisfy the following formula 1.

[0054] [Formula 1]

[0055] 0.1 < a / b [μm / %] < 0.5

[0056] In Formula 1, "a" may be the D of the pulverized conductive additive 23. 50 Particle size [μm], "b" may be the porosity [%] of the negative electrode 20. The porosity may be the ratio of the pores 24 contained in a unit volume. The method for measuring the porosity is not particularly limited. For example, after measuring the true density of the negative electrode 20 by a gas replacement method (pycnometer method) or a liquid replacement method (Archimedes method), the film density of the negative electrode 20 is calculated using the following formula.

[0057] Thin film density=weight of negative electrode 20 / (film thickness×area of ​​negative electrode 20).

[0058] The porosity can be calculated using the following formula using the true density and the film density.

[0059] Porosity [%] = (true density - film density) / true density × 100.

[0060] When the negative electrode 20 satisfies Formula 1, the pulverized conductive additive 23 can offset the defect that the electron conduction path is blocked by the pores 24. When Formula 1 is satisfied, the pulverized conductive additive 23 can be uniformly dispersed in the negative electrode 20 without aggregation, thereby forming an electron conduction path.

[0061] The porosity of the negative electrode 20 may be in the range of 0.1% to 70%, 0.1% to 40%, or 0.1% to 30%.

[0062] Examples of the binder may include butadiene rubber (BR), nitrile rubber (NBR), hydrogenated nitrile rubber (HNBR), polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), carboxymethyl cellulose (CMC), etc. The binder in the negative electrode 20 may be present in a granular form, a linear form, or the like.

[0063] The method of manufacturing the negative electrode 20 may include preparing a starting material by mixing a raw conductive additive and a pulverizing medium. The method may also include obtaining a pulverized conductive additive by pulverizing the starting material using a resonance method. The method may also include preparing a mixture comprising a pulverized conductive additive, a negative electrode active material, a solid electrolyte, and a binder. The method may additionally include using the mixture to manufacture a negative electrode.

[0064] The pulverizing medium is not particularly limited, but may include, for example, zirconia balls or the like.

[0065] The starting material can be prepared by introducing a pulverized medium and a raw conductive additive into a container having a predetermined internal space and mixing the introduced pulverized medium and the raw conductive additive. The mass (M) of the raw conductive additive 1 ) and the mass of the crushing medium (M 2) ratio (M 1 / M 2 ) can be higher than 0.125 and lower than 8. When the ratio (M 1 / M 2 ) falls within the above numerical range, the original conductive additive can be effectively crushed.

[0066] The pulverized conductive additive can be obtained by pulverizing a starting material using a resonance method. Figure 3 An example of a pulverization process using a resonance method is shown. Resonance-based pulverization can involve mixing and pulverizing by applying acoustic and vibration energy to the sample. Figure 3 As shown in , when the sample oscillates vertically, the subharmonic beam irradiates the sample so that Faraday waves appear, thereby providing strong shear and collision forces to the sample.

[0067] Specifically, in the step of obtaining the pulverized conductive additive, a resonance frequency higher than 0 Hz and lower than 100 Hz may be applied to the starting material. At the same time, in the step of obtaining the pulverized conductive additive, a gravitational acceleration in the range of 20 G to 80 G may be applied to the starting material for more than 2 minutes and less than 10 minutes.

[0068] The pulverized conductive additive obtained in this manner can be mixed with a negative electrode active material, a solid electrolyte, and a binder to obtain a mixture. Then, using this mixture, a negative electrode can be manufactured.

[0069] The method of obtaining the mixture is not particularly limited. For example, the pulverized conductive additive, negative electrode active material, solid electrolyte, binder, etc. may be introduced into a solvent that does not react with the components and then stirred to obtain a mixture in the form of slurry.

[0070] The method for manufacturing the negative electrode 20 is not particularly limited. For example, the mixture in the form of slurry may be coated on a substrate and dried to manufacture the negative electrode 20 .

[0071] The solid electrolyte layer 30 may have a sheet form having at least two main surfaces facing each other. Each of the two main surfaces may be a plane mathematically, and a portion thereof may also include a uniform curved surface. Alternatively, protrusions and depressions formed during the formation of the solid electrolyte layer 30 may be included. In this regard, the sheet form is not limited to a relatively thin rectangular parallelepiped form.

[0072] In the solid electrolyte layer 30 in the form of a sheet, the distance between two main surfaces facing each other can be the thickness of the solid electrolyte layer 30. The length of the solid electrolyte layer 30 in a first direction (e.g., the width direction) perpendicular to the thickness direction is greater than its thickness. Additionally, the length of the solid electrolyte layer 30 in a second direction (e.g., the length direction) orthogonal to both the thickness direction and the first direction is greater than its thickness.

[0073] The thickness of the solid electrolyte layer 30 is not particularly limited, but can be in the range of 1 μm to 100 μm. The thickness of the solid electrolyte layer 30 can refer to the average value obtained when measuring the measurement target at five points.

[0074] The solid electrolyte layer 30 can contain a solid electrolyte having lithium ion conductivity, a binder, etc.

[0075] The solid electrolyte can be the same as or different from the solid electrolyte contained in the negative electrode 20. The solid electrolyte can contain at least one of an oxide-based solid electrolyte, a sulfide-based solid electrolyte, or a combination thereof. Additionally, the solid electrolyte can be in a crystalline, amorphous, or combined form thereof. The oxide-based solid electrolyte and the sulfide-based solid electrolyte can be the same as those described above.

[0076] Examples of the binder can include butadiene rubber (BR), nitrile rubber (NBR), hydrogenated nitrile rubber (HNBR), polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), carboxymethyl cellulose (CMC), etc. The binder in the solid electrolyte layer 30 can exist in a particulate form, a linear form, etc.

[0077] The positive electrode 20 can contain a positive electrode active material, a solid electrolyte, a conductive additive, a binder, etc.

[0078] The positive electrode active material can contain a lithium transition metal oxide configured to store and release lithium.

[0079] The lithium transition metal oxide can contain any material common in the field to which the present invention pertains. For example, the lithium transition metal oxide can contain LiNi x1 Co x2 Mn x3 O 2 (0.65 ≤ x1 ≤ 0.85, 0.05 < x2 < 0.25, 0.03 < x3 < 0.2, and x1 + x2 + x3 = 1).

[0080] The D 50 particle size of the positive electrode active material is not particularly limited, but can be, for example, in the range of 1 μm to 20 μm.

[0081] The positive electrode active material can be coated with an alkali metal oxide.

[0082] The alkali metal oxide may contain an alkali metal element, a transition metal element, and a substituent element.

[0083] The alkali metal element may include at least one of lithium (Li), sodium (Na), potassium (K), or a combination thereof. In one embodiment, the alkali metal element includes lithium (Li).

[0084] The transition metal element may include any transition metal element commonly used in the field to which the present invention belongs. For example, the transition metal element may include at least one of niobium (Nb), tantalum (Ta), zirconium (Zr) or a combination thereof.

[0085] The solid electrolyte may be responsible for the movement of lithium ions in the positive electrode 40. The solid electrolyte may be the same as or different from the solid electrolyte of the negative electrode 20 and the solid electrolyte layer 30. The solid electrolyte may include at least one of an oxide-based solid electrolyte, a sulfide-based solid electrolyte, or a combination thereof. In addition, the solid electrolyte may be crystalline, amorphous, or a combination thereof. The oxide-based solid electrolyte and the sulfide-based solid electrolyte are the same as those described above.

[0086] Examples of the conductive additive may include carbon black, conductive graphite, acetylene black, graphene, carbon nanotubes, carbon nanofibers, vapor-grown carbon fibers, and the like.

[0087] Examples of the binder may include butadiene rubber (BR), nitrile rubber (NBR), hydrogenated nitrile rubber (HNBR), polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), carboxymethyl cellulose (CMC), etc. The binder in the positive electrode 40 may be present in a granular form, a linear form, etc.

[0088] The positive electrode 40 may include 70 wt % to 90 wt % of a positive electrode active material, 10 wt % to 15 wt % of a solid electrolyte, 1 wt % to 5 wt % of a conductive additive, and 1 wt % to 5 wt % of a binder. However, the content of each component may be appropriately adjusted in consideration of the desired capacity and efficiency of the all-solid-state battery.

[0089] The thickness of the positive electrode 40 is not particularly limited, but may be in the range of 1 μm to 100 μm. The thickness of the positive electrode 40 may refer to an average value obtained when measuring the measurement target at five points. In addition, the thickness of the positive electrode 40 may refer to the thickness of the all-solid-state battery in a discharged state.

[0090] The positive electrode current collector 50 may include a conductive substrate having a plate-like form. For example, the positive electrode current collector 10 may have a sheet, a film, or a foil form.

[0091] The positive electrode current collector 50 may include aluminum foil.

[0092] The thickness of the positive electrode current collector 50 is not particularly limited, but may be, for example, in the range of 1 μm to 500 μm.

[0093] Another embodiment of the present invention is described in more detail below by the following examples. The following examples are provided only to enhance the understanding of the present invention. The scope of the present invention is not limited thereto.

[0094] Example 1

[0095] The original conductive additive was crushed using the resonance method to obtain D 50 A pulverized conductive additive having a particle size of about 8 μm. After preparing a slurry containing the pulverized conductive additive, a silicon-based negative electrode active material, a sulfide-based solid electrolyte, and a binder, the slurry is applied to a negative electrode collector and dried to manufacture a negative electrode. The porosity of the negative electrode and whether Formula 1 is satisfied are shown in Table 1. A nickel foil having a thickness of about 10 μm is used as a negative electrode collector.

[0096] A solid electrolyte layer having a thickness ranging from about 30 μm to 50 μm is stacked on the negative electrode.

[0097] The positive electrode and the positive electrode current collector are stacked on the solid electrolyte layer to obtain an all-solid-state battery. The loading amount of the positive electrode active material in the positive electrode is about 24 mg / cm 2 , and an aluminum foil with a thickness of about 12 μm was used as the positive electrode collector.

[0098] The N / P ratio in the all-solid-state battery is adjusted to about 1.2.

[0099] Example 2

[0100] The all-solid-state battery was manufactured in the same manner as in Example 1, except that the D of the original conductive additive was changed. 50 The particle size and porosity of the negative electrode are shown in Table 1.

[0101] Comparative Example 1

[0102] The all-solid-state battery was manufactured in the same manner as in Example 1, except that the D of the original conductive additive was changed. 50 The particle size and porosity of the negative electrode are shown in Table 1.

[0103] Comparative Example 2

[0104] The all-solid-state battery was manufactured in the same manner as in Example 1, except that the D of the original conductive additive was changed. 50 The particle size and porosity of the negative electrode are shown in Table 1.

[0105] Comparative Example 3

[0106] An all-solid-state battery was manufactured in the same manner as in Example 1, except that the original conductive additive was used instead of the pulverized conductive additive.

[0107] Figure 4A Analysis results of the negative electrode according to Example 1 are shown, wherein the analysis was performed using a scanning electron microscope (SEM). Figure 4B The analysis results of the negative electrode according to Example 1 are shown, in which the analysis was performed using energy dispersive X-ray spectroscopy (EDS).

[0108] Figure 5A The SEM analysis results of the negative electrode according to Comparative Example 3 are shown. Figure 5B The EDS analysis results of the negative electrode according to Comparative Example 3 are shown.

[0109] From the above results, it can be seen that in Example 1, the pulverized conductive additive is uniformly distributed in the negative electrode, while the original conductive additive in Comparative Example 3 is aggregated.

[0110] Figure 6 Evaluation results of charge and discharge characteristics of the all-solid-state batteries according to Examples 1 and 2 and Comparative Examples 1 and 2 are shown. Figure 7 The evaluation results of the capacity retention rate of the all-solid-state batteries according to Examples 1 and 2 and Comparative Examples 1 and 2 are shown. Each all-solid-state battery was charged and discharged under the following conditions: temperature about 30°C, voltage level in the range of 2.0 to 4.25V; charging rate 0.2C.

[0111] [Table 1]

[0112]

[0113] [Formula 1] 0.1 50 Particle size [μm], "b" is the porosity of the negative electrode [%].

[0114] Depend on Figure 6 and Figure 7 As can be seen from Table 1, both the initial efficiency and the capacity retention rate in Examples 1 and 2 are better than those in Comparative Examples 1 and 2.

[0115] Although the present invention has been shown and described with reference to the embodiments of the present invention, it should be understood that the scope of the present invention is not limited to the embodiments described. Modifications are also included within the scope of the present invention.​

Claims

1. A negative electrode for an all-solid-state battery, the negative electrode comprising: Negative electrode active material; Solid electrolytes; A pulverized conductive additive; and Binder, in, The negative electrode satisfies 0.1 The negative electrode active material comprises a silicon-based negative electrode active material. Where a is the D of the pulverized conductive additive expressed in microns. 50 a is the particle size, and b is the porosity of the negative electrode expressed as a percentage.

2. The negative electrode for an all-solid-state battery according to claim 1, wherein The pulverized conductive additive includes carbon black.

3. The negative electrode for an all-solid-state battery according to claim 1, wherein The porosity of the negative electrode is in the range of 0.1% to 70%.

4. The negative electrode for an all-solid-state battery according to claim 1, wherein The D of the pulverized conductive additive 50 The particle size ranges from 1 μm to 20 μm.

5. The negative electrode for an all-solid-state battery according to claim 1, wherein:

9. A method for manufacturing a negative electrode for an all-solid-state battery, the method comprising:

6. The negative electrode for an all-solid-state battery according to claim 1, wherein: The negative electrode active material D 50 The particle size ranges from 1 μm to 50 μm.

7. The negative electrode for an all-solid-state battery according to claim 1, wherein: The solid electrolyte D 50 The particle size ranges from 0.1 μm to 10 μm.

8. The negative electrode for an all-solid-state battery according to claim 1, wherein: The solid electrolyte D 50 The particle size D1 is related to the D 50 The ratio D1 / D2 of the particle diameter D2 is 1 or less. The starting material is prepared by mixing a raw conductive additive and a pulverizing medium; obtaining a pulverized conductive additive by pulverizing a starting material; preparing a mixture comprising a pulverized conductive additive, a negative electrode active material, a solid electrolyte, and a binder; and The mixture is used to manufacture a negative electrode, wherein the negative electrode satisfies 0.1 The ratio M1 / M2 of the mass M1 of the original conductive additive to the mass M2 of the pulverized medium is higher than 0.125 and lower than 8. Obtaining the pulverized conductive additive includes pulverizing the starting material using a resonance method. Where a is the D of the pulverized conductive additive expressed in microns. 50 a is the particle size, and b is the porosity of the negative electrode expressed as a percentage.

10. The method for producing a negative electrode for an all-solid-state battery according to claim 9, wherein: Obtaining the pulverized conductive additive includes applying a resonance frequency higher than 0 Hz and lower than 100 Hz to the starting material.

11. The method for producing a negative electrode for an all-solid-state battery according to claim 9, wherein: Obtaining the pulverized conductive additive includes pulverizing the starting material by applying a gravitational acceleration in a range of 20G to 80G.

12. The method for producing a negative electrode for an all-solid-state battery according to claim 9, wherein: Obtaining the pulverized conductive additive includes pulverizing the starting material by applying gravitational acceleration for more than 2 minutes and less than 10 minutes.

13. The method for producing a negative electrode for an all-solid-state battery according to claim 9, wherein: The pulverized conductive additive includes carbon black.

14. The method for producing a negative electrode for an all-solid-state battery according to claim 9, wherein: The porosity of the negative electrode is in the range of 0.1% to 70%.

15. The method for producing a negative electrode for an all-solid-state battery according to claim 9, wherein: ​ 16. The method for producing a negative electrode for an all-solid-state battery according to claim 9, wherein: The D of the pulverized conductive additive 50 The particle size ranges from 1 μm to 20 μm.

17. The method for producing a negative electrode for an all-solid-state battery according to claim 9, wherein: ​ 18. The method for producing a negative electrode for an all-solid-state battery according to claim 9, wherein: The negative electrode active material D 50 The particle size ranges from 1 μm to 50 μm.

19. The method for producing a negative electrode for an all-solid-state battery according to claim 9, wherein: The solid electrolyte D 50 The particle size ranges from 0.1 μm to 10 μm.

20. The method for producing a negative electrode for an all-solid-state battery according to claim 9, wherein: The solid electrolyte D 50 The particle size D1 is related to the D 50 The ratio D1 / D2 of the particle diameter D2 is 1 or less.

Images