Anode for all-solid-state battery and all-solid-state battery including same

Abstract

The invention relates to an anode for an all-solid-state battery and an all-solid-state battery including the same. The anode includes a structure having a current collector layer, a first anode active material layer, and a second anode active material layer stacked in this order. The first anode active material layer includes a first solid electrolyte, a first anode active material, a first binder, and a punctiform first conductive material. The second anode active material layer includes a second solid electrolyte, a second anode active material, a second binder, and a linear second conductive material. The average particle size of the first solid electrolyte is smaller than that of the second solid electrolyte.

Description

[0001] Cross - reference to related applications

[0002] This application claims the benefit of priority to Korean Patent Application No. 10 - 2023 - 0178076, filed with the Korean Intellectual Property Office on December 8, 2023, the entire contents of which are incorporated herein by reference. Technical field

[0003] The present disclosure relates to an anode for an all - solid - state battery and an all - solid - state battery including the anode. Background art

[0004] In terms of battery capacity, stability, output, magnification, miniaturization, etc., various batteries that can overcome the limitations of current lithium secondary batteries are being studied. Among battery types, an all - solid - state battery refers to a battery that uses a solid electrolyte instead of the electrolyte used in existing lithium secondary batteries. The all - solid - state battery does not use a flammable solvent in the battery. Therefore, there is no risk of fire or explosion caused by decomposition reactions of existing electrolytes, etc., thus greatly improving battery stability.

[0005] Since the all - solid - state battery uses a solid electrolyte, it is difficult for the solid electrolyte to easily penetrate into the pores of the active material layer. Therefore, it is difficult to ensure sufficient ionic (e.g., lithium - ion) conductivity in the region adjacent to the current collector layer within the active material layer. In addition, due to the characteristics of the all - solid - state battery using the above - mentioned solid electrolyte, it is difficult to ensure sufficient electron conductivity in the region far from the current collector layer within the active material layer.

[0006] In addition, in order to increase the energy density of the all - solid - state battery, recently, research has been conducted to apply an anode active material having a relatively large volume change rate caused by the operation of the all - solid - state battery. In this case, due to the relatively large volume change rate of the anode active material, the contact between the solid electrolyte and the conductive material may be lost. This can lead to a decrease in ionic conductivity and electron conductivity within the anode of the all - solid - state battery. Summary of the invention

[0007] The present disclosure has been made to solve the above - mentioned problems that occur in the prior art while maintaining the advantages achieved by the prior art.

[0008] One aspect of the present disclosure provides an anode for an all - solid - state battery that can solve the above - mentioned problems.

[0009] The technical problems to be solved by the present disclosure are not limited to the above - mentioned problems. Those of ordinary skill in the art to which the present disclosure pertains should more clearly understand any other technical problems not mentioned herein from the following description.

[0010] According to one aspect of the present disclosure, an anode for a all-solid-state battery includes a structure having a current collector layer, a first anode active material layer, and a second anode active material layer stacked in sequence. The first anode active material layer includes a first solid electrolyte, a first anode active material, a first binder, and a dot-shaped first conductive material. The second anode active material layer includes a second solid electrolyte, a second anode active material, a second binder, and a linear second conductive material. The average particle size (D50) of the first solid electrolyte is smaller than the average particle size (D50) of the second solid electrolyte.

[0011] According to another aspect of the present disclosure, a all-solid-state battery includes: the anode for a all-solid-state battery described above; a cathode for a all-solid-state battery; and a solid electrolyte layer interposed between the cathode for a all-solid-state battery and the anode for a all-solid-state battery. Detailed Description

[0012] Hereinafter, the anode for a all-solid-state battery and the all-solid-state battery including the anode are described in detail so that those of ordinary skill in the art can practice the anode and the all-solid-state battery including the anode.

[0013] Anode for all-solid-state battery

[0014] The anode for a all-solid-state battery of the present disclosure includes a structure in which a current collector layer, a first anode active material layer, and a second anode active material layer are stacked in sequence.

[0015] Current collector layer

[0016] The type and shape of the current collector layer are not particularly limited as long as the current collector layer is conductive without causing chemical changes in the all-solid-state battery.

[0017] For example, the current collector layer may include copper, stainless steel, aluminum, nickel, titanium, calcined carbon, carbon, nickel, titanium, silver, etc. surface-treated copper or stainless steel and / or aluminum cadmium alloy. The current collector can have various forms, such as a film, sheet, foil, net, porous body, foam, non-woven fabric, etc.

[0018] First anode active material layer

[0019] The first anode active material layer may include a first anode active material, a first binder, a first solid electrolyte, and a first conductive material.

[0020] The type of the first anode active material may not be particularly limited, and various types of known anode active materials commonly used for the anode of a all-solid-state battery can be used without limitation.

[0021] In one embodiment, the first anode active material may include at least one silicon-based anode active material. The silicon-based anode active material may have a relatively high theoretical capacity, and thus, a all-solid-state battery applying the first anode active material including the silicon-based anode active material may have a high capacity and energy density.

[0022] The type of the first binder may not be particularly limited, and various types of known binders generally used for anodes of all-solid-state batteries may be used without limitation. For example, as the first binder, an acrylic binder, a polyvinylidene fluoride (PVDF) binder, a polytetrafluoroethylene (PTFE) binder, or a butadiene rubber binder such as nitrile rubber (NBR) may be used.

[0023] The type of the first solid electrolyte may not be particularly limited, and various types of known solid electrolytes generally used for anodes of all-solid-state batteries may be used without limitation. For example, as the first solid electrolyte, one selected from the group consisting of sulfide-based solid electrolytes, oxide-based solid electrolytes, polymer solid electrolytes, or any combination or composition thereof may be used.

[0024] In one embodiment, the first solid electrolyte in the first anode active material layer may exist in the form of particles. In this regard, the first solid electrolyte in the form of particles may be used to provide a transport path for ions (e.g., lithium ions) by filling the space between the first conductive material, the first binder, and the first anode active material.

[0025] In one implementation, the first solid electrolyte may have a smaller average particle diameter (D50) than the second solid electrolyte included in the second anode active material layer, which will be described below. In this case, the first solid electrolyte having a relatively small average particle diameter more effectively fills the space between the first conductive material, the first binder, and the first anode active material. Therefore, the porosity within the first anode active material layer may be relatively reduced. Accordingly, sufficient ion transport paths may be ensured within the first anode active material layer disposed adjacent to the current collector layer.

[0026] In one implementation, the average particle diameter (D50) of the first solid electrolyte may be in the range from 0.5 μm to 2.0 μm, and in one example may be from 0.8 μm to 1.5 μm. When the average particle diameter (D50) of the first solid electrolyte satisfies the above numerical range, since the first solid electrolyte forms an optimal network in the space between the first conductive material, the first binder, and the first anode active material, an ion transport path may be formed more effectively. Accordingly, the first anode active material layer disposed adjacent to the current collector layer may have very excellent ion conductivity.

[0027] The first conductive material can be a dot-shaped conductive material. In this regard, the dot-shaped conductive material can refer to a conductive material that is substantially spherical or elliptical or has a similar shape and thus has a relatively small BET (Brunauer-Emmett-Teller) specific surface area.

[0028] In this regard, when the first conductive material is a dot-shaped conductive material, the content of the first conductive material can be relatively reduced on the surface of the first anode active material layer facing the current collector layer, and the content of the first binder can be relatively increased. Therefore, as the content of the first binder on the surface of the first anode active material layer facing the current collector layer increases, the adhesion between the current collector layer and the first anode active material layer can be improved.

[0029] In one implementation, the BET specific surface area of the first conductive material can be in the range from 50 m 2 / g to 100 m 2 / g, and in one example can be from 65 m 2 / g to 80 m 2 / g. When the BET specific surface area of the first conductive material satisfies the above numerical range, due to optimizing the content of the first binder on the surface of the first anode active material layer facing the current collector layer, the adhesion between the current collector layer and the first anode active material layer can become very excellent.

[0030] In one implementation, the first conductive material can have an average aspect ratio (i.e., the converted length of the conductive material divided by the width of the cross-section perpendicular to the longitudinal direction of the material) that is equal to or greater than 2 and equal to or less than 10. In some examples, the average aspect ratio can be equal to or greater than 2.5, equal to or greater than 3, equal to or greater than 3.5, or equal to or greater than 4, and can be equal to or less than 9.5, equal to or less than 9, equal to or less than 8.5, equal to or less than 8, equal to or less than 7.5, or equal to or less than 7. In this regard, when the average aspect ratio of the first conductive material satisfies the above numerical range, due to optimizing the content of the first binder on the surface of the first anode active material layer facing the current collector layer, the adhesion between the current collector layer and the first anode active material layer can become very excellent. When the average aspect ratio of the first conductive material is too high, the contact rate with the conductive material in the first anode active material layer increases, which can increase the probability of side reactions occurring at the conductive material - electrolyte interface in the electrode.

[0031] In one example, for 10 randomly selected first conductive materials, for the cross-section of the anode active material layer (unit area: 2*10 -2 mm 2) It is possible to take an electron microscope photograph (magnification: 1000 times). In this case, the above-mentioned average aspect ratio refers to the average value of the values obtained by dividing the corresponding length (in the case of a curved conductive material, the converted length when extended in a straight line) by the width of the cross-section perpendicular to the longitudinal direction.

[0032] In one implementation, the first conductive material may include at least one selected from the group consisting of carbon black, Ketjen black, acetylene black, crystalline carbon, or any combination thereof or consisting of them.

[0033] Second anode active material layer

[0034] The second anode active material layer may include a second anode active material, a second binder, a second solid electrolyte, and a second conductive material.

[0035] The type of the second anode active material may not be particularly limited. Without limitation, various types of known anode active materials commonly used for the anode of all-solid-state batteries can be used.

[0036] In this case, the second anode active material may at least include a silicon-based anode active material similar to the first anode active material. When a silicon-based anode active material with a relatively high theoretical capacity is used as the second anode active material, the all-solid-state battery using the second anode active material can have a high capacity and energy density.

[0037] The type of the second binder may not be particularly limited, and various types of known binders commonly used for the anode of all-solid-state batteries can be used without limitation. For example, as the second binder, an acrylic binder, a polyvinylidene fluoride (PVDF) binder, a polytetrafluoroethylene (PTFE) binder, or a butadiene rubber binder such as nitrile rubber (NBR) can be used. In this case, the second binder may be the same as or different from the first binder.

[0038] The type of the second solid electrolyte may not be particularly limited, and various types of known solid electrolytes commonly used for the anode of all-solid-state batteries can be used without limitation. For example, as the second solid electrolyte, one selected from the group consisting of sulfide-based solid electrolytes, oxide-based solid electrolytes, polymer solid electrolytes, or any combination thereof or consisting of them can be used. In this case, the second solid electrolyte may be the same as or different from the first solid electrolyte.

[0039] In one implementation, the second solid electrolyte in the second anode active material layer may exist in the form of particles. In this regard, the second solid electrolyte in particulate form can be used to provide a path for ion transport by filling the space between the second conductive material, the second binder, and the second anode active material.

[0040] In one implementation, the second solid electrolyte may have a larger average particle size (D50) than the first solid electrolyte. In this case, the second solid electrolyte with a relatively large average particle diameter may have high tolerance to moisture introduced from the outside, and thus can compensate for the moisture vulnerability derived from the first solid electrolyte with a relatively small average particle diameter.

[0041] In one implementation, the average particle diameter (D50) of the second solid electrolyte may be in the range from 2.5 μm to 4.5 μm, and in one example may be from 2.9 μm to 4.3 μm. When the average particle diameter (D50) of the second solid electrolyte satisfies the above numerical range, while effectively playing the role of compensating for the above moisture vulnerability, the second solid electrolyte can effectively fill the space between the second conductive material, the second binder, and the second anode active material. Therefore, a sufficient ion transport path can be provided.

[0042] The second conductive material may be a linear conductive material. In this regard, the linear conductive material may refer to a conductive material having a substantially straight or curved fiber form or a similar shape and thus having a relatively large BET specific surface area.

[0043] In this regard, the second conductive material can be used to provide a path for electrons within the second anode active material layer. In this case, when the second conductive material is the linear conductive material as described above, entanglement, contact, etc. between the second conductive materials can occur even in a region relatively far from the current collector layer. Therefore, a path for electrons within the second anode active material layer can be effectively provided.

[0044] Furthermore, even when the volume change rate of the second anode active material is relatively large, such as when the second anode active material includes a silicon-based anode active material, the linear second conductive material can effectively accommodate the volume change of the second anode active material. Therefore, the life characteristics of the all-solid-state battery can be improved.

[0045] In one implementation, the BET specific surface area of the second conductive material may be in the range from 180 m 2 / g to 300 m 2 / g, and in one example may be from 200 m 2 / g to 250 m 2 / g. When the BET specific surface area of the second conductive material satisfies the above numerical range, although the electron conductivity in the second anode active material layer can be excellent because the electron transport path is sufficiently provided in the second anode active material layer, the second conductive material can effectively accept the volume change of the second anode active material.

[0046] In one implementation, the average aspect ratio of the second conductive material can be equal to or greater than 50 and equal to or less than 100. In some examples, the average aspect ratio can be equal to or greater than 55, equal to or greater than 58, or equal to or greater than 60, and equal to or less than 95, equal to or less than 90, equal to or less than 85, equal to or less than 80, equal to or less than 75, or equal to or less than 70. In one example, the second conductive material can have an average length in the range from 5 μm to 50 μm. In this regard, when the average aspect ratio and / or average length of the second conductive material satisfy the above numerical range, although the electron conductivity in the second anode active material layer can be very excellent because the electron transport path is sufficiently provided in the second anode active material layer, the second conductive material can effectively accept the volume change of the second anode active material. Specifically, because the porosity of the second anode active material layer is greater than the porosity of the above first anode active material layer, by applying the second conductive material with a higher average aspect ratio to the second anode active material layer, due to the thin and long morphological characteristics of the second conductive material, an appropriate contact rate and high conductivity can be ensured.

[0047] In one implementation, the second conductive material can include carbon nanotubes (e.g., at least one selected from the group consisting of single-walled carbon nanotubes, double-walled carbon nanotubes, multi-walled carbon nanotubes, or any combination thereof or composed of them) or carbon nanofibers.

[0048] Laminated structure of current collector layer, first anode active material layer and second anode active material layer

[0049] The anode for an all-solid-state battery of the present disclosure has a laminated structure of a current collector layer, a first anode active material layer, and a second anode active material layer.

[0050] In this regard, as described above, in the first anode active material layer adjacent to the current collector layer, the dot-like first conductive material can play a role in improving the adhesion to the current collector layer. Moreover, the first solid electrolyte having a relatively small average particle size can play a role in ensuring the ionic conductivity in the region adjacent to the current collector layer.

[0051] In addition, as described above, in the second anode active material layer spaced apart from the current collector layer, the linear second conductive material can play a role in ensuring electron conductivity in a region away from the current collector layer and accommodating the volume expansion of the second anode active material. Moreover, the second solid electrolyte having a relatively large average particle diameter can play a role in ensuring moisture tolerance.

[0052] In this case, in one implementation, the thickness T2 of the second anode active material layer can be greater than the thickness T1 of the first anode active material layer. In one example, the thickness of the first anode active material layer can be in the range from 20 μm to 40 μm, and the thickness of the second anode active material layer can be in the range from 50 μm to 70 μm.

[0053] Specifically, the thickness T2 of the second anode active material layer and the thickness T1 of the first anode active material layer can satisfy the following Formula 1 and Formula 2.

[0054] The first anode active material layer using the small-diameter solid electrolyte has a smaller porosity than the second anode active material layer. Therefore, when prepared with the same composition and composition ratio as the second anode active material layer, the thickness of the first anode active material layer may be expected to be smaller than the thickness of the second anode active material layer. When the thickness of the second anode active material layer is appropriately greater than that of the first anode active material layer and the value of T1 / (T1 + T2) is equal to or less than 0.5, moisture stability can be effectively ensured. Moreover, when the value of T1 / (T1 + T2) is equal to or greater than 0.25, all the advantages of the first anode active material layer and the second anode active material layer can be appropriately ensured.

[0055] Formula 1

[0056] 0.25 ≤ T1 / (T1 + T2) ≤ 0.5

[0057] Formula 2

[0058] 70 μm ≤ T1 + T2 ≤ 110 μm;

[0059] All-solid-state battery

[0060] The all-solid-state battery of the present disclosure can include the anode for the all-solid-state battery described above. More specifically, the all-solid-state battery can include an anode for the all-solid-state battery, a cathode for the all-solid-state battery, and a solid electrolyte layer interposed between the cathode for the all-solid-state battery and the anode for the all-solid-state battery.

[0061] In this regard, the types of the cathode and the solid electrolyte layer for the all-solid-state battery may not be particularly limited. Without limitation, various known cathodes and solid electrolyte layers commonly used for all-solid-state batteries can be used.

[0062] In the following, the present disclosure is described in more detail by way of examples. However, such examples are only intended to aid in understanding the present disclosure. The scope of the present disclosure is not limited to such examples in any way.

[0063] Preparation Examples 1-7: Preparation of anode for all-solid-state battery

[0064] A mixture is prepared by dry-mixing a first anode active material (silicon-graphite composite (Si-G)), a first solid electrolyte, and a first conductive material with each other using a mixer. The prepared mixture is put into a solvent together with a first binder (rubber-based binder solution) and a dispersant, and mixed using a mixer. Then the mixture is coated on a current collector and dried sufficiently at 90 °C to form a first anode active material layer.

[0065] Thereafter, a mixture is prepared by dry-mixing a second anode active material (silicon-graphite composite (Si-G)), a second solid electrolyte, and a second conductive material with each other using a mixer. The prepared mixture is put into a solvent together with a second binder (rubber-based binder solution) and a dispersant, and mixed using a mixer. Then the mixture is coated on the first anode active material layer and dried sufficiently at 90 °C. Thereafter, the obtained product is heated at 120 °C for 4 hours to prepare an anode for an all-solid-state battery, which has a laminated structure including a current collector layer, a first anode active material layer (thickness: 30 μm), and a second anode active material layer (thickness: 60 μm).

[0066] In each of Preparation Examples 1-7, a first solid electrolyte, a first conductive material, a second solid electrolyte, and a second binder as shown in Table 1 below were used.

[0067] Table 1

[0068]

[0069]

[0070] 1) Aspect ratio of carbon black: 5

[0071] 2) Aspect ratio of carbon nanotubes (CNT): 60 to 70

[0072] 3) Average length of linear conductive material (CNT): 10 μm

[0073] Example 1: All-solid-state battery

[0074] Using the anode for all-solid-state battery prepared based on Preparation Example 1 above, an all-solid-state battery is manufactured, which includes an anode for all-solid-state battery, a cathode for all-solid-state battery, and a solid electrolyte layer interposed between the anode for all-solid-state battery and the cathode for all-solid-state battery.

[0075] Comparative Example 1: All-solid-state battery

[0076] Using the anode for all-solid-state battery prepared based on Preparation Example 2 above, an all-solid-state battery is manufactured, which includes an anode for all-solid-state battery, a cathode for all-solid-state battery, and a solid electrolyte layer interposed between the anode for all-solid-state battery and the cathode for all-solid-state battery.

[0077] Comparative Example 2: All-solid-state battery

[0078] Using the anode for all-solid-state battery prepared based on Preparation Example 3 above, an all-solid-state battery is manufactured, which includes an anode for all-solid-state battery, a cathode for all-solid-state battery, and a solid electrolyte layer interposed between the anode for all-solid-state battery and the cathode for all-solid-state battery.

[0079] Comparative Example 3: All-solid-state battery

[0080] Using the anode for all-solid-state battery prepared based on Preparation Example 4 above, an all-solid-state battery is manufactured, which includes an anode for all-solid-state battery, a cathode for all-solid-state battery, and a solid electrolyte layer interposed between the anode for all-solid-state battery and the cathode for all-solid-state battery.

[0081] Comparative Example 4: All-solid-state battery

[0082] Using the anode for all-solid-state battery prepared based on Preparation Example 5 above, an all-solid-state battery is manufactured, which includes an anode for all-solid-state battery, a cathode for all-solid-state battery, and a solid electrolyte layer interposed between the anode for all-solid-state battery and the cathode for all-solid-state battery.

[0083] Comparative Example 5: All-solid-state battery

[0084] Using the anode for all-solid-state battery prepared based on Preparation Example 6 above, an all-solid-state battery is manufactured, which includes an anode for all-solid-state battery, a cathode for all-solid-state battery, and a solid electrolyte layer interposed between the anode for all-solid-state battery and the cathode for all-solid-state battery.

[0085] Comparative Example 6: All-solid-state battery

[0086] Using the anode for all-solid-state batteries prepared based on Preparation Example 7 described above, an all-solid-state battery is manufactured that includes an anode for all-solid-state batteries, a cathode for all-solid-state batteries, and a solid electrolyte layer interposed between the anode for all-solid-state batteries and the cathode for all-solid-state batteries.

[0087] Experimental Example: Evaluation of characteristics of all-solid-state battery

[0088] The 0.05C discharge capacity and the direct current internal resistance (DC-IR) of the all-solid-state batteries of Example 1 and Comparative Examples 1-6 were measured, and the results are shown in Table 2. The specific measurement method is as described in the following measurement method.

[0089] Table 2

[0090] 0.05C discharge capacity DC-IR Example 1 185 mAh / g 10.3 Ω Comparative Example 1 170 mAh / g 12.5 Ω Comparative Example 2 172 mAh / g 12.5 Ω Comparative Example 3 175 mAh / g 12.0 Ω Comparative Example 4 165 mAh / g 13.0 Ω Comparative Example 5 170 mAh / g 12.5 Ω Comparative Example 6 167 mAh / g 12.5 Ω

[0091] Measurement method

[0092] 0.05C discharge capacity measurement method

[0093] The 0.05C reference capacity for discharging for 20 hours was calculated based on the cathode half-cell reference capacity, and then the current value based on the amount of the cathode active material in each of the examples and comparative examples was calculated, applied, and measured using the 0.05C reference capacity. Specifically, the all-solid-state batteries manufactured in the examples and comparative examples were charged with a current of 0.05C until the voltage reached 4.3V, and after cutting off at the upper limit voltage, they were discharged with a current of 0.05C until the voltage reached 2.5V to measure the discharge capacity.

[0094] DC-IR measurement method

[0095] The DC-IR was measured as follows. The all-solid-state battery was charged with a constant current of 0.05C in the first cycle, then put into dormancy, discharged to 50% of the state of charge (SOC) at the same current, and then put into dormancy again for a certain period of time. Thereafter, a high current pulse 5 times or more than 5 times the current value of 0.05C was injected, and the voltage change between the dormant state and the high current pulse injection state was measured to calculate the resistance based on this voltage change, and the current value was calculated using Ohm's law.

[0096] Referring to Table 2, determine the all-solid-state batteries of Comparative Example 1 that use carbon black with a relatively small BET specific surface area as the second conductive material; the all-solid-state batteries of Comparative Example 2 that use CNT with a relatively high BET specific surface area as the first conductive material; the all-solid-state batteries of Comparative Example 3 that use a battery with a relatively large average particle size as the first solid electrolyte; the all-solid-state batteries of Comparative Example 4 that use a battery with a relatively small average particle size as the second solid electrolyte; the all-solid-state batteries of Comparative Example 5 that use a battery with a relatively large average particle size as the first solid electrolyte and carbon black with a relatively small BET specific surface area as the second conductive material; and the all-solid-state batteries of Comparative Example 6 that use a battery with a relatively large average particle size as the first solid electrolyte and a battery with a relatively small average particle size as the second solid electrolyte are inferior to the all-solid-state batteries of Example 1 in both the 0.05C discharge capacity and DC-IR characteristics.

[0097] The first anode active material layer in the present disclosure is an active material layer disposed adjacent to the current collector layer. In the first anode active material layer, a dot-shaped first conductive material having a relatively small BET specific surface area can be used to improve the adhesion to the current collector layer. Moreover, a first solid electrolyte having a relatively small average particle size can be used to ensure ionic conductivity in the region adjacent to the current collector layer.

[0098] In addition, the second anode active material layer in the present disclosure is an active material layer disposed spaced apart from the current collector layer, with the first anode active material layer interposed therebetween. In the second anode active material layer, a linear second conductive material having a relatively large BET specific surface area can be used to ensure electron conductivity in the region far from the current collector layer and to accommodate the volume expansion of the second anode active material. Moreover, a second solid electrolyte having a relatively large average particle size can be used to ensure moisture tolerance.

[0099] The anode for an all-solid-state battery in the present disclosure can have a laminated structure in which a current collector layer, a first anode active material layer, and a second anode active material layer are laminated in sequence. In this regard, since the components in each of the first anode active material layer and the second anode active material layer included in the laminated structure play the above-mentioned roles, the anode for an all-solid-state battery can exhibit excellent stability and excellent charge and discharge efficiency.

[0100] In the above, although the present disclosure has been described with reference to the embodiments, the present disclosure is not limited thereto. Without departing from the spirit and scope of the present disclosure claimed in the appended claims, those of ordinary skill in the art to which the present disclosure pertains can make various modifications and changes to the embodiments.

Claims

1. An anode for an all-solid-state battery, the anode comprising: A structure with the following stacked in order: a current collector layer; a first anode active material layer; as well as a second anode active material layer, The first anode active material layer comprises a first solid electrolyte, a first anode active material, a first binder and a dot-shaped first conductive material. wherein the second anode active material layer comprises a second solid electrolyte, a second anode active material, a second binder and a linear second conductive material, and The average particle size of the first solid electrolyte is smaller than the average particle size of the second solid electrolyte.

2. The anode according to claim 1, wherein The average particle size of the first solid electrolyte is in a range from 0.5 μm to 2.0 μm, and wherein the average particle size of the second solid electrolyte is in a range from 2.5 μm to 4.5 μm.

3. The anode according to claim 1, wherein Each of the first solid electrolyte and the second solid electrolyte independently includes a sulfide-based solid electrolyte, an oxide-based solid electrolyte, a polymer solid electrolyte, or any combination thereof.

4. The anode according to claim 1, wherein The BET specific surface area of ​​the first conductive material is in the range of 50 m 2 / g to 100m 2 / g, and wherein the BET specific surface area of ​​the second conductive material is in the range of 180 m 2 / g to 300m 2 / g range.

5. The anode according to claim 1, wherein The first conductive material includes carbon black, Ketjen black, acetylene black, crystalline carbon, or any combination thereof.

6. The anode according to claim 1, wherein The second conductive material includes carbon nanotubes or carbon nanofibers.

7. The anode according to claim 6, wherein The carbon nanotubes include single-walled carbon nanotubes, double-walled carbon nanotubes, multi-walled carbon nanotubes, or any combination thereof.

8. The anode according to claim 1, wherein The average aspect ratio of the first conductive substance is equal to or greater than 2 and equal to or less than 10, and wherein the average aspect ratio of the second conductive substance is equal to or greater than 50 and equal to or less than 100.

9. The anode according to claim 1, wherein An average length of the second conductive substance ranges from 5 μm to 50 μm.

10. The anode according to claim 1, wherein Each of the first anode active material and the second anode active material includes a silicon-based anode active material.

11. The anode according to claim 1, wherein The thickness T2 of the second anode active material layer is greater than the thickness T1 of the first anode active material layer.

12. The anode according to claim 11, wherein The thickness T2 of the second anode active material layer and the thickness T1 of the first anode active material layer satisfy the following formula 1 and formula 2: Formula 1: 0.25 ≤ T1 / (T1+T2) ≤ 0.5, and Formula 2: 70μm≤T1+T2≤110μm.

13. An all-solid-state battery, comprising: The anode for an all-solid-state battery according to claim 1; cathodes for all-solid-state batteries; as well as A solid electrolyte layer is disposed between the cathode for the all-solid-state battery and the anode for the all-solid-state battery.

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