Apparatus for manufacturing all-solid-state battery and manufacturing method using the same

Abstract

Disclosed are an apparatus for manufacturing an all-solid-state battery and a manufacturing method using the same. The apparatus for manufacturing an all-solid-state battery includes a mold unit including a first hole vertically extended to have the same shape and width as those of the all-solid-state battery and a second hole horizontally extended to be in horizontal communication with the first hole, a first pressing unit including a first protrusion member corresponding to the first hole, the first protrusion member being combined with an upper portion of the mold unit and pressing a raw material of the all-solid-state battery filling the first hole downward, and a second pressing unit including a second protrusion member corresponding to the first hole, the first protrusion member being combined with a lower portion of the mold unit and pressing the raw material of the all-solid-state battery filling the first hole upward.

Description

Technical Field

[0001] This application relates to an apparatus for manufacturing an all-solid-state battery including a reference electrode and a manufacturing method using the apparatus. Background Technology

[0002] Among existing batteries used as secondary batteries, lithium-ion batteries have demonstrated one of the best performance. However, lithium-ion batteries inherently carry the risk of fire and explosion due to their structure. For example, oxygen is contained in the cathode active material, and the liquid electrolyte acts as fuel at high temperatures and can therefore ignite.

[0003] Specifically, when events such as lithium dendrite formation, separator defects, overcharging, and impacts on the battery cell occur, a large current flows, leading to the dissolution of the separator, exposure of the anode, and a further increase in battery temperature, resulting in the decomposition of the cathode material and the release of oxygen. Ultimately, oxygen, heat, and fuel come into contact with each other, thus burning the liquid electrolyte.

[0004] Therefore, research is actively underway on next-generation batteries with higher energy density and stability than lithium-ion batteries.

[0005] One of the most promising types is the all-solid-state battery. An all-solid-state battery is a battery in which the electrolyte is solid. Therefore, all materials in the battery are solid.

[0006] Because all-solid-state batteries contain a solid electrolyte that does not pose a risk of evaporation due to temperature changes or leakage due to external impacts, they exhibit excellent stability. Furthermore, they do not experience volume expansion and can function normally even in extreme external environments with high heat and high pressure.

[0007] Furthermore, its output can be significantly increased. Unlike lithium-ion batteries that include a liquid electrolyte, in all-solid-state batteries, there is no desolvation reaction that separates lithium ions from the solvent during charging and discharging. The charge-discharge reaction is directly related to the diffusion reaction of lithium ions in the solid, thus enabling high output.

[0008] Solid-state batteries also offer the advantage of a wide operating temperature range. Compared to traditional liquid electrolytes, they ensure stable performance over a broader temperature range. In particular, high ionic conductivity is desired at low temperatures. One issue with electric vehicles is that battery performance deteriorates in winter, reducing range. With the advent of solid-state batteries, this anxiety related to low temperatures will be resolved.

[0009] The performance of all-solid-state batteries, as described above, can be evaluated using various metrics such as charge / discharge capacity, charge / discharge characteristics, high-temperature discharge characteristics, low-temperature discharge characteristics, stability, and lifespan. However, to date, no standardized performance specifications have been established.

[0010] Such all-solid-state batteries may develop defects during use or immediately after manufacturing. Without revealing the cause of the defect, it is impossible to prevent the occurrence of defects in another battery.

[0011] The current method for detecting defective products is to select batteries with causes of failure, such as insufficient capacity or short circuits caused by X-ray imaging. Therefore, it will be important to more accurately measure and analyze properties such as the capacity of the active materials and the electrochemical reactions of the electrodes.

[0012] The information included in the background section is intended only to enhance the understanding of the general background of this application and should not be construed as an admission or representation in any form that such information constitutes prior art known to those skilled in the art. Summary of the Invention

[0013] The purpose of this application is to provide a method for measuring and analyzing the electrochemical properties of all-solid-state batteries without disassembling them.

[0014] Another objective of this application is to provide an all-solid-state battery that stably emits electrochemical signals.

[0015] Another objective of this application is to provide an all-solid-state battery that emits electrochemical signals without distortion.

[0016] The purpose of this application is not limited to the foregoing, and other purposes will be clearly understood from the following description and achieved by the means and combinations thereof described in the claims.

[0017] According to one aspect of this application, an apparatus for manufacturing an all-solid-state battery includes: a mold unit comprising: a first hole extending vertically to have the same shape and width as the all-solid-state battery; and a second hole extending horizontally to communicate horizontally with the first hole; a first pressing unit including a first protrusion corresponding to the first hole, the first protrusion engaging with the upper part of the mold unit and pressing downwards onto the material of the all-solid-state battery filling the first hole; and a second pressing unit including a second protrusion corresponding to the first hole, the second protrusion engaging with the lower part of the mold unit and pressing upwards onto the material of the all-solid-state battery filling the first hole.

[0018] The mold unit may also include an insulating member positioned on the surface side of the first hole.

[0019] The mold unit may also include an insulating member positioned on the surface side of the second hole.

[0020] The first pressing unit and the second pressing unit may include conductive materials.

[0021] According to another aspect of this application, a method for manufacturing an all-solid-state battery includes: joining a second pressing unit to the lower part of a mold unit such that a second protruding member extends through a first hole; adding a first solid electrolyte powder to the second protruding member; joining the first pressing unit to the upper part of the mold unit such that the first protruding member extends through the first hole and pressing the first solid electrolyte powder to form a first solid electrolyte layer; removing the first pressing unit and inserting a reference electrode into a second hole and placing the reference electrode on the first solid electrolyte layer; adding a second solid electrolyte powder to the reference electrode; joining the first pressing unit to the upper part of the mold unit such that the first protruding member fits into the first hole and pressing the second solid electrolyte powder to form a second solid electrolyte layer; removing the first pressing unit and placing a negative electrode layer on the second solid electrolyte layer; removing the second pressing unit and placing a positive electrode layer on the first solid electrolyte layer; and combining the mold unit, the first pressing unit, and the second pressing unit, and compressing the combined structure within the first hole.

[0022] The first solid electrolyte powder and the second solid electrolyte powder may include sulfide-based solid electrolytes.

[0023] The reference electrode may include a wire, which includes at least one selected from the group consisting of tungsten (W), aluminum (Al), nickel (Ni), stainless steel (SUS), and combinations thereof, and is coated with at least one noble metal selected from the group consisting of gold (Au), silver (Ag), platinum (Pt), and combinations thereof.

[0024] The manufacturing method may also include inserting the stop unit into the second hole so that the structure in the first hole is not exposed to the outside through the second hole.

[0025] According to another aspect of this application, a method for manufacturing an all-solid-state battery includes: combining a second pressing unit with the lower part of a mold unit such that a second protruding member extends through a first hole; disposing a positive electrode layer on the second protruding member; adding a first solid electrolyte powder to the positive electrode layer; combining a first pressing unit with the upper part of the mold unit such that a first protruding member of the first pressing unit is adapted to the first hole, thereby pressing the first solid electrolyte powder to form a first solid electrolyte layer; removing the first pressing unit and inserting a reference electrode into a second hole, and disposing the reference electrode on the first solid electrolyte layer; adding a second solid electrolyte powder to the reference electrode; combining the first pressing unit with the upper part of the mold unit such that the first protruding member extends through the first hole and presses the second solid electrolyte powder to form a second solid electrolyte layer; removing the first pressing unit and disposing a negative electrode layer on the second solid electrolyte layer; and combining the mold unit, the first pressing unit, and the second pressing unit, and compressing the structure within the first hole.

[0026] The first solid electrolyte powder and the second solid electrolyte powder may include sulfide-based solid electrolytes.

[0027] The reference electrode may include a wire, which includes at least one selected from the group consisting of tungsten (W), aluminum (Al), nickel (Ni), stainless steel (SUS), and combinations thereof, and is coated with at least one noble metal selected from the group consisting of gold (Au), silver (Ag), platinum (Pt), and combinations thereof.

[0028] The manufacturing method may also include inserting the stop unit into the second hole, such that the structure in the first hole is not exposed to the outside through the second hole.

[0029] According to the present invention, since the powdered solid electrolyte and the reference electrode are simultaneously compressed to manufacture the battery, the contact performance between the reference electrode and the solid electrolyte is superior compared to the prior art. Therefore, a stable electrochemical signal can be obtained using the reference electrode.

[0030] Furthermore, according to this application, since the solid electrolyte is formed very uniformly, the all-solid-state battery can be operated smoothly when an analysis is performed using a reference electrode inserted therein.

[0031] Furthermore, since no other materials such as conductive paste are applied between the reference electrode and the solid electrolyte in this application, the signal of the reference electrode is not distorted due to other materials, and therefore the resulting values ​​are highly reliable.

[0032] Furthermore, in this application, since the inner wall of the mold cell and the vicinity of the reference electrode, which may cause a short circuit, are insulated, the all-solid-state battery can be used without being separated from the mold cell after manufacturing. Therefore, there is no problem of connecting the current collector after separating the all-solid-state battery from the mold cell, and damage to the battery that may occur during the separation process can be avoided.

[0033] The effects of this application are not limited to those described above, and should be understood to include all effects that can be reasonably expected from the following description. Attached Figure Description

[0034] Figure 1 An apparatus for manufacturing all-solid-state batteries according to this application is shown;

[0035] Figure 2 It shows Figure 1 Manufacturing equipment and all-solid-state batteries manufactured using that equipment;

[0036] Figure 3 Another embodiment of the manufacturing apparatus according to this application is shown;

[0037] Figure 4A , 4B Figures 4C, 4D, 4E and 4F are reference figures illustrating a portion of a method for manufacturing an all-solid-state battery according to this application;

[0038] Figure 5 This is a reference diagram showing the form in which the reference electrode is inserted in this application;

[0039] Figure 6A and 6B This is a reference diagram illustrating a portion of a method for manufacturing an all-solid-state battery according to this application;

[0040] Figure 7A and 7B The results are shown by analyzing the cross-section around the reference electrode of the all-solid-state battery according to the embodiment at different scales using an electron scanning microscope.

[0041] Figure 8A and 8B The results are shown by analyzing the cross-section around the reference electrode of a comparative all-solid-state battery using scanning electron microscopy.

[0042] Figure 9A The results obtained by measuring the potential signals of the positive and negative electrodes of the all-solid-state battery according to the embodiment are shown; and

[0043] Figure 9B The results are shown by measuring the potential signals of the positive and negative electrodes of a comparative all-solid-state battery. Detailed Implementation

[0044] The above and other objects, features, and advantages of this application will become clearer from the following exemplary embodiments, taken in conjunction with the accompanying drawings. However, this application is not limited to the embodiments disclosed herein and may be modified in different forms. These embodiments are provided to fully explain this application and to fully convey the spirit of this application to those skilled in the art.

[0045] Throughout the accompanying drawings, the same reference numerals denote the same or similar elements. For clarity of this application, the dimensions of structures are described as larger than their actual dimensions. It should be understood that although terms such as "first," "second," etc., may be used herein to describe various elements, these elements are not limited by these terms. These terms are used only to distinguish one element from another. For example, an element referred to below as "first" may be called "second" without departing from the scope of this application. Similarly, a "second" element may also be called "first." As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise.

[0046] It will also be understood that, when used in this specification, the terms "comprising," "including," "having," etc., specify the presence of the stated features, integers, steps, operations, elements, components, or combinations thereof, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof. Furthermore, it should be understood that when an element such as a layer, film, region, or sheet is referred to as being "on" another element, it may be directly on the other element, or intermediate elements may exist therein. Similarly, when an element such as a layer, film, region, or sheet is referred to as being "under" another element, it may be directly under the other element, or intermediate elements may exist therein.

[0047] Unless otherwise specified, all figures, values, and / or representations indicating the amounts of components, reaction conditions, polymer compositions, and mixtures used herein should be considered approximate, including the various uncertainties inherent in the measurement that affect the acquisition of these values, and should therefore be understood to be modified by the term "about" in all cases. Furthermore, when numerical ranges are disclosed in this specification, the ranges are continuous and include all values ​​from the minimum to the maximum of the range, unless otherwise specified. Additionally, when such ranges involve integer values, all integers from the minimum to the maximum are included, unless otherwise specified.

[0048] A reference electrode is defined as an electrode with a stable electrochemical potential, which serves as a reference point for measuring the potential of one or more electrodes in an electrochemical cell.

[0049] Korean Patent No. 10-1530812 (hereinafter referred to as "Patent Document 1") discloses a method for manufacturing an all-solid-state battery, wherein a reference electrode is inserted between solid electrolyte layers. A conductive paste is used to bond the solid electrolyte and the reference electrode.

[0050] Specifically, in Patent Document 1, a conductive paste is applied to a solid electrolyte, and a reference electrode is pressed onto the conductive paste. As a result, the interface between the solid electrolyte and the reference electrode deforms or the interfacial contact between them decreases, making it difficult for the reference electrode to detect a reliable positive or negative electrode signal.

[0051] Furthermore, according to Patent Document 1, it is difficult to obtain a reliable solid electrolyte resistance because the conductive paste deforms the solid electrolyte resistance between the reference electrode and the positive electrode.

[0052] In the case of Patent Document 1, the conductive paste causes contact problems between the solid electrolytes located above and below the reference electrode, thus reducing the movement of lithium ions in the solid electrolyte layer. Ultimately, since the signal obtained through the reference electrode is from an all-solid-state battery in an abnormal operating state, it is impossible to accurately determine the state of the battery.

[0053] This application aims to overcome the limitations of the prior art as described above. In this application, conductive paste is not used, and the powdered solid electrolyte is compressed together with the reference electrode, so that the interface between the two components is uniformly formed and lithium ions move smoothly within the solid electrolyte layer.

[0054] Furthermore, in the manufacturing equipment according to this application, since an insulating member is provided in the mold unit, the structure obtained without separating the all-solid-state battery from the mold unit can be used as a battery.

[0055] The application will be described in detail below.

[0056] Figure 1 An apparatus for manufacturing all-solid-state batteries according to this application is shown. Figure 2 It shows Figure 1 Manufacturing equipment for and all-solid-state batteries manufactured using the same equipment. According to this application, it is possible to... Figure 2 The all-solid-state battery is driven in the state shown, and its performance can be evaluated by collecting electrochemical signals from the all-solid-state battery.

[0057] Reference Figure 1 and Figure 2The manufacturing apparatus includes: a mold unit 10 providing a molding space for an all-solid-state battery; a first pressing unit 20 coupled to the upper portion of the mold unit 10; and a second pressing unit 30 coupled to the lower portion of the mold unit 10. For reference, in this specification, "upper portion" and "lower portion" are based on the illustrated state, and the application is not limited thereto. Specifically, in any embodiment, if the first pressing unit 20 and the second pressing unit 30 are coupled to the mold unit 10 in opposite directions based on the mold unit 10, then this configuration should be considered to be within the scope of this application, and not limited to the terms "upper portion" and "lower portion".

[0058] The mold unit 10 may include a main body member 11, a first hole 12 and a second hole 13. The first hole 12 is formed vertically through the main body member 11 so as to have the same shape and width as the all-solid-state battery. The second hole 13 is formed through the main body member 11 so as to communicate horizontally with the first hole 12.

[0059] The mold unit 10 may also include an insulating member 14 positioned on the surface side of the first hole 12 and / or the surface side of the second hole 13.

[0060] The first pressing unit 20 includes a first substrate 21 and a first protruding member 22, the first protruding member 22 being formed to protrude from the first substrate 21 and having a shape corresponding to the shape of the first hole 12.

[0061] When the first pressing unit 20 is combined with the mold unit 10, the first substrate 21 is configured to function as a stop member. The first substrate 21 may have a plate-like structure, which is formed to have an area larger than that of the first hole 12.

[0062] The first protruding member 22 is configured to fit into the first hole 12, thereby pressing the raw material in the mold unit 10.

[0063] like Figure 2 As shown, finally, the first pressing unit 20 contacts the negative electrode layer 90 via the first protruding member 22. In this application, the first substrate 21 and the first protruding member 22 are configured to include conductive material, thereby the first pressing unit 20 acts as a current collector relative to the negative electrode layer 90.

[0064] The second pressing unit 30 includes a second substrate 31 and a second protruding member 32, the second protruding member 32 being formed to protrude from the second substrate 31 and having a shape corresponding to the shape of the first hole 12.

[0065] When the second pressing unit 30 is combined with the mold unit 10, the second substrate 31 is configured to function as a stop. The second substrate 31 may have a plate-like structure, which is formed to have an area larger than that of the first hole 12.

[0066] The second protruding member 32 is configured to fit into the first hole 12, thereby pressing the raw material in the mold unit 10.

[0067] like Figure 2 As shown, finally, the second pressing unit 30 contacts the positive electrode layer 80 via the second protruding member 32. In this application, the second substrate 31 and the second protruding member 32 are configured to include conductive material, thereby the second pressing unit 30 serves as a current collector relative to the positive electrode layer 80.

[0068] Figure 3 Another embodiment of the manufacturing apparatus according to this application is shown. In this embodiment, instead of performing the pressing in the vertical direction as in the above embodiments, the pressing is performed only in any one direction, and preferably only by the first pressing unit 20, and the second pressing unit 30 is implemented by a plate-shaped base substrate. However, this application is not limited to this, and the first pressing unit 20 may be plate-shaped and the pressing may be performed by the second pressing unit 30.

[0069] Figure 4A , Figure 4B , Figure 4C , Figure 4D , Figure 4E , Figure 4F , Figure 5 , Figure 6A and Figure 6B This is a reference diagram illustrating a method for manufacturing an all-solid-state battery according to this application.

[0070] In the following text, reference will be made to Figure 4A , Figure 4B , Figure 4C , Figure 4D , Figure 4E , Figure 4F , Figure 5 , Figure 6A and Figure 6B Describe the manufacturing method in chronological order.

[0071] Reference Figure 4A In this manufacturing method, firstly, the second pressing unit 30 is coupled to the lower part of the mold unit 10, such that the second protruding member 32 of the second pressing unit 30 is adapted into the first hole 12. Then, the first solid electrolyte powder A is added to the second protruding member 32 of the second pressing unit 30.

[0072] In this application, instead of inserting a pre-formed solid electrolyte layer into the mold unit 10, solid electrolyte powder is added and then pressed together with the reference electrode 60, as will be described later, thereby forming a first solid electrolyte layer 50 and a second solid electrolyte layer 70. Thus, a uniform interface is formed between the first solid electrolyte layer 50, the second solid electrolyte layer 70, and the reference electrode 60.

[0073] The first solid electrolyte powder A may include a sulfide-based solid electrolyte. Examples of sulfide-based solid electrolytes may include Li₂S-P₂S₅, Li₂S-P₂S₅-LiI, Li₂S-P₂S₅-LiCl, Li₂S-P₂S₅-LiBr, Li₂S-P₂S₅-Li₂O, Li₂S-P₂S₅-Li₂O-LiI, Li₂S-SiS₂, Li₂S-SiS₂-LiI, Li₂S-SiS₂-LiBr, Li₂S-SiS₂-LiCl, Li₂S-SiS₂-B₂S₃-LiI, Li₂S-SiS₂-P₂S₅-LiI, Li₂S-B₂S₃, and Li₂S-P₂S₅-Z. m S n (m and n are positive numbers, and Z is any one of Ge, Zn, and Ga), Li2S-GeS2, Li2S-SiS2-Li3PO4, Li2S-SiS2-Li x MO y (x and y are positive numbers, and M is any one of P, Si, Ge, B, Al, Ga, and In), and Li 10 GeP2S 12 .

[0074] Reference Figure 4B The first pressing unit 20 is coupled to the upper part of the mold unit 10, so that the first protruding member 22 of the first pressing unit 20 is adapted into the first hole 12, thereby pressing the first solid electrolyte powder A. As a result, the following can be obtained: Figure 4C The first solid electrolyte layer 50 is shown.

[0075] After that, as Figure 4D As shown, the first pressing unit 20 is removed and the reference electrode 60 is inserted through the second hole 13, thereby setting the reference electrode 60 on the first solid electrolyte layer 50.

[0076] like Figure 5 As shown, the reference electrode 60 is provided with a space to prevent contact with the insulating member 14 disposed on the surface side of the second hole 13. This is to prevent the reference electrode 60 from being damaged by the insulating member 14 when the volume of the first solid electrolyte layer 50 and the second solid electrolyte layer 70 decreases due to subsequent compression of the all-solid-state battery.

[0077] The reference electrode 60 may include a wire, which includes at least one selected from the group consisting of tungsten (W), aluminum (Al), nickel (Ni), stainless steel (SUS), and combinations thereof, and is coated with at least one noble metal selected from the group consisting of gold (Au), silver (Ag), platinum (Pt), and combinations thereof.

[0078] There are no particular restrictions on the material of the wire, and any material can be used as long as it has low reactivity relative to the solid electrolyte, such as tungsten (W) and aluminum (Al), nickel (Ni) and stainless steel (SUS) with strength comparable to tungsten.

[0079] Since the reference electrode 60 is an electrical wire, it is not used for the physical separation of the first solid electrolyte layer 50 and the second solid electrolyte layer 70 as a separation membrane.

[0080] After setting the reference electrode 60, as follows Figure 4E As shown, the second solid electrolyte powder B is added to the reference electrode 60.

[0081] The second solid electrolyte powder B may include a sulfide-based solid electrolyte. Examples of sulfide-based solid electrolytes may include Li₂S-P₂S₅, Li₂S-P₂S₅-LiI, Li₂S-P₂S₅-LiCl, Li₂S-P₂S₅-LiBr, Li₂S-P₂S₅-Li₂O, Li₂S-P₂S₅-Li₂O-LiI, Li₂S-SiS₂, Li₂S-SiS₂-LiI, Li₂S-SiS₂-LiBr, Li₂S-SiS₂-LiCl, Li₂S-SiS₂-B₂S₃-LiI, Li₂S-SiS₂-P₂S₅-LiI, Li₂S-B₂S₃, and Li₂S-P₂S₅-Z. m S n (m and n are positive numbers, and Z is any one of Ge, Zn, and Ga), Li2S-GeS2, Li2S-SiS2-Li3PO4, Li2S-SiS2-Li x MO y (x and y are positive numbers, and M is any one of P, Si, Ge, B, Al, Ga, and In) and Li 10 GeP2S 12 The second solid electrolyte powder B may be the same as or different from the first solid electrolyte powder A.

[0082] After that, as Figure 4FAs shown, the first pressing unit 20 can be combined with the upper part of the mold unit 10, so that the first protruding member 22 of the first pressing unit 20 is adapted to the first hole 12, thereby pressing the second solid electrolyte powder B, thereby forming the second solid electrolyte layer 70.

[0083] Through the above process, a structure can be obtained in which the reference electrode 60 is inserted between the first solid electrolyte layer 50 and the second solid electrolyte layer 70. In obtaining this structure, the first pressing unit 20 and the second pressing unit 30 can apply pressure only sufficient to maintain the shape of a series of layers of the first solid electrolyte powder A and the second solid electrolyte powder B. That is, a low pressure is applied for flattening, rather than the high pressure applied as in the dry manufacturing of all-solid-state batteries.

[0084] Subsequently, the first pressing unit 20 is removed, and the negative electrode layer 90 is disposed on the second solid electrolyte layer 70. Furthermore, the second pressing unit 30 is removed, and the positive electrode layer 80 is disposed on the first solid electrolyte layer 50.

[0085] like Figure 6A As shown, when a structure comprising a positive electrode layer 80, a first solid electrolyte layer 50, a reference electrode 60, a second solid electrolyte layer 70, and a negative electrode layer 90, arranged sequentially from bottom to top, is completed in the first hole 12 of the mold unit 10, the first pressing unit 20 and the second pressing unit 30 are simultaneously driven to press the structure under high pressure. As a result, a structure comprising... Figure 6B The reference electrode 60 shown is an all-solid-state battery.

[0086] Compared to the insulating member 14 disposed on the surface side of the second hole 13, the reference electrode 60 does not need to be further lowered, but must be in a position that is at least in contact with the insulating member 14.

[0087] Furthermore, the stop unit 40 is inserted into the second hole 13 of the mold unit 10, so that the structure is not exposed to the outside. It is preferable to use the stop unit 40 which includes an elastic insulating material.

[0088] The manufacturing method described above involves forming a first solid electrolyte layer 50, a reference electrode 60, and a second solid electrolyte layer 70, followed by the addition of a positive electrode layer 80 and a negative electrode layer 90. However, the manufacturing method of this application is not limited to this, and as will be described later, the same all-solid-state battery can be obtained by first adding a positive electrode layer 80, forming the first solid electrolyte layer 50, the reference electrode 60, and the second solid electrolyte layer 70 on the positive electrode layer 80, and then adding a negative electrode layer 90.

[0089] Specifically, another embodiment of the manufacturing method according to this application may include: combining the second pressing unit 30 with the lower part of the mold unit 10, such that the second protruding member 32 of the second pressing unit 30 is adapted into the first hole 12; disposing of the positive electrode layer 80 on the second protruding member 32 of the second pressing unit 30; adding the first solid electrolyte powder A to the positive electrode layer 80; combining the first pressing unit 20 with the upper part of the mold unit 10, such that the first protruding member 22 of the first pressing unit 20 is adapted into the first hole 12, thereby pressing the first solid electrolyte powder A to form the first solid electrolyte layer 50; and removing the first pressing unit 20. The reference electrode 60 is inserted into the second hole 13, thereby setting the reference electrode on the first solid electrolyte layer 50. The second solid electrolyte powder B is added to the reference electrode 60. The first pressing unit 20 is combined with the upper part of the mold unit 10, so that the first protruding member 22 of the first pressing unit 20 is adapted into the first hole 12, thereby pressing the second solid electrolyte powder B to form the second solid electrolyte layer 70. The first pressing unit 20 is removed and the negative electrode layer 90 is set on the second solid electrolyte layer 70. The mold unit 10, the first pressing unit 20 and the second pressing unit 30 are combined to compress the structure in the first hole 12.

[0090] The present application will be described in more detail below through specific embodiments. The following embodiments are merely examples to help understand the present application, and the scope of the present application is not limited thereto.

[0091] Example

[0092] use Figure 4A , Figure 4B , Figure 4C , Figure 4D , Figure 4E , Figure 4F , Figure 5 , Figure 6A and Figure 6B The method shown fabricates an all-solid-state battery including a reference electrode. As the reference electrode, a 50 μm diameter wire comprising tungsten (W) is used, coated with gold (Au) to a thickness of 0.5 μm. A sulfide-based solid electrolyte powder is used.

[0093] Comparative Example

[0094] Using the same materials as in the embodiments and the same method as in Patent Document 1, wherein a reference electrode is connected using conductive paste and then inserted between two completed solid electrolyte layers, an all-solid-state battery is manufactured.

[0095] Experimental Example 1 - Analysis of the Cross Section

[0096] Observe the interface between the reference electrode and the solid electrolyte in the all-solid-state batteries according to the embodiments and comparative examples. The side surface of each all-solid-state battery was cut using an ion beam cross-section polisher, and its interface was observed by scanning electron microscopy.

[0097] Figure 7A and 7B The results show the cross-section around the reference electrode of the all-solid-state battery according to an embodiment. Figure 8A and 8B The results show the cross-section around the reference electrode of a comparative all-solid-state battery.

[0098] See Figure 7A and 7B As can be seen, in this application, the reference electrode and the solid electrolyte are in good contact with each other without any separation. In contrast, see [link to previous application]. Figure 8A and 8B It can be seen that in the case of an all-solid-state battery manufactured using the method of Patent Document 1, the reference electrode and the solid electrolyte are separated from each other in most areas and their contact performance is very poor.

[0099] Experiment Example 2 - Measurement of Electric Potential Signal

[0100] The potential signals of the positive and negative electrodes were measured using reference electrodes of all-solid-state batteries according to the embodiments and comparative examples.

[0101] In the comparative example, to measure the potential signal, the all-solid-state battery had to be separated from the mold. However, due to the difficulty of separation, a large external force was applied, which damaged the battery. Therefore, in the comparative example of this Experimental Example 2, as in Patent Document 1, a conductive paste was used to connect the reference electrode and insert it between the two completed solid electrolyte layers, and the all-solid-state battery was manufactured using the manufacturing equipment according to this application.

[0102] Figure 9A The results of an all-solid-state battery according to an embodiment are shown. Figure 9B The results are shown based on a comparative example of an all-solid-state battery.

[0103] Reference Figure 9A As can be seen, in the case of the all-solid-state battery according to the embodiment, the potential signals of the positive and negative electrodes are measured very stably. In contrast, see [link to relevant documentation]. Figure 9B As can be seen, in the case of the comparative example, the potential signals of the positive and negative electrodes are very unstable.

[0104] While specific embodiments of this application have been described with reference to the accompanying drawings, those skilled in the art will understand that this application can be implemented in other specific forms without altering its technical spirit or essential features. Therefore, the above embodiments should be understood in various ways as non-limiting and exemplary.

Claims

1. An apparatus for manufacturing all-solid-state batteries, comprising: The mold unit includes: A first hole, the first hole extending vertically to have the same shape and width as the all-solid-state battery; and A second hole, which extends horizontally to communicate horizontally with the first hole; A first pressing unit, comprising a first protruding member corresponding to the first hole, the first protruding member being coupled to the upper part of the mold unit and configured to press downwards the raw material of the all-solid-state battery filling the first hole; and The second pressing unit includes a second protruding member corresponding to the first hole. The second protruding member is coupled to the lower part of the mold unit and configured to press upwards the raw material of the all-solid-state battery filling the first hole. The mold unit further includes insulating members disposed adjacent to each other to define the first hole. The mold unit further includes insulating members disposed adjacent to each other to define the second hole. The first pressing unit and the second pressing unit include conductive materials and are used after the all-solid-state battery is manufactured without being separated from the mold unit.

2. A method for manufacturing an all-solid-state battery including a reference electrode using the apparatus of claim 1, comprising: The second pressing unit is combined with the lower part of the mold unit such that the second protruding member extends through the first hole; Add the first solid electrolyte powder to the second protruding member; The first pressing unit is combined with the upper part of the mold unit, such that the first protruding member extends through the first hole, thereby pressing the first solid electrolyte powder to form a first solid electrolyte layer. Remove the first pressing unit and insert the reference electrode into the second hole, and place the reference electrode on the first solid electrolyte layer; Add the second solid electrolyte powder to the reference electrode; The first pressing unit is combined with the upper part of the mold unit, such that the first protruding member extends through the first hole and presses the second solid electrolyte powder, thereby forming a second solid electrolyte layer; Remove the first pressing unit and set a negative electrode layer on the second solid electrolyte layer; Remove the second pressing unit and deposit a positive electrode layer on the first solid electrolyte layer; and The mold unit, the first pressing unit, and the second pressing unit are combined and compressed within the first hole to form a combined structure.

3. The method according to claim 2, wherein, The first solid electrolyte powder and the second solid electrolyte powder comprise sulfide-based solid electrolytes.

4. The method according to claim 2, wherein, The reference electrode includes a wire, which includes at least one selected from the group consisting of tungsten, aluminum, nickel, stainless steel, and combinations thereof, and is coated with at least one noble metal selected from the group consisting of gold, silver, platinum, and combinations thereof.

5. The method of claim 2, further comprising inserting a stop unit into the second hole to prevent the coupling structure in the first hole from being exposed to the outside through the second hole.

6. A method for manufacturing an all-solid-state battery including a reference electrode using the apparatus of claim 1, comprising: The second pressing unit is combined with the lower part of the mold unit such that the second protruding member extends through the first hole; A positive electrode layer is disposed on the second protruding member; Add the first solid electrolyte powder onto the positive electrode layer; The first pressing unit is combined with the upper part of the mold unit, such that the first protruding member extends through the first hole and presses the first solid electrolyte powder, thereby forming a first solid electrolyte layer; Remove the first pressing unit and insert the reference electrode into the second hole, and place the reference electrode on the first solid electrolyte layer; Add the second solid electrolyte powder to the reference electrode; The first pressing unit is combined with the upper part of the mold unit, such that the first protruding member extends through the first hole and presses the second solid electrolyte powder, thereby forming a second solid electrolyte layer; Remove the first pressing unit and set a negative electrode layer on the second solid electrolyte layer; and The mold unit, the first pressing unit, and the second pressing unit are combined and compressed within the first hole to form a combined structure.

7. The method according to claim 6, wherein, The first solid electrolyte powder and the second solid electrolyte powder comprise sulfide-based solid electrolytes.

8. The method according to claim 6, wherein, The reference electrode includes a wire, the wire comprising at least one selected from the group consisting of tungsten, aluminum, nickel, stainless steel, and combinations thereof, and the wire is coated with at least one noble metal selected from the group consisting of gold, silver, platinum, and combinations thereof.

9. The method of claim 6, further comprising inserting a stop unit into the second hole to prevent the engagement structure in the first hole from being exposed to the outside through the second hole.

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