Solid electrolyte glass, method for manufacturing same, and all-solid-state battery manufactured using same

Abstract

The present invention relates to a solid electrolyte glass, a method for manufacturing same, and an all-solid-state battery using same. The solid electrolyte glass comprises composite particles comprising: core portions containing first glass particles; and coating portions coupled to the surfaces of the core portions and formed of second glass particles. A solid electrolyte prepared from the solid electrolyte glass can exhibit high ionic conductivity, thereby enhancing the performance of an all-solid-state battery.

Description

Solid electrolyte glass, method for manufacturing the same, and all-solid-state battery manufactured using the same

[0001] The present invention relates to a powdery solid electrolyte glass used in the manufacture of a solid electrolyte, a method for manufacturing the solid electrolyte glass, and an all-solid-state battery (specifically, an all-solid-state secondary battery) manufactured using the solid electrolyte glass.

[0002] Lithium-ion batteries (LiBs) boast a higher energy density per unit volume than other battery systems, making them a popular choice for most electronic devices. Their applications are expanding beyond compact size to include automotive and energy storage devices. However, because most current LiBs use liquid electrolytes, safety concerns regarding explosion and ignition persist.

[0003] To address the aforementioned safety issues, all-solid-state batteries are attracting attention, fundamentally preventing explosions and ignition by replacing liquid electrolytes with solid ones. The application of solid electrolytes can address battery safety concerns and theoretically increase energy density by two to three times compared to lithium-ion batteries. Furthermore, by eliminating processes like the LiB degassing process in the battery manufacturing process, the company can improve battery efficiency while achieving cost savings through simplification.

[0004] The above-mentioned all-solid-state batteries can be broadly classified into oxide-based all-solid-state batteries and sulfide-based all-solid-state batteries depending on the type of solid electrolyte. The oxide-based all-solid-state batteries have a simple manufacturing process, do not require controlled manufacturing environment atmosphere, and have high chemical / thermal stability, offering advantages in stability over sulfide-based all-solid-state batteries.

[0005] However, the oxide-based all-solid-state battery requires a high heat treatment temperature during the sintering process for battery manufacturing, which has the problem that the electrodes may decompose or an interface reaction may occur. Specifically, crystalline materials such as LLZO, LLTO, or LATP / LAGP are used as oxide-based solid electrolyte materials, and these require a high sintering temperature of 900°C or higher for crystallization. However, when a sintering temperature of 900°C or higher is applied during the process of manufacturing an oxide-based all-solid-state battery using a simple manufacturing process such as the MLCB process, decomposition of the positive and negative electrodes or an interface reaction between the positive / negative electrode materials and the electrolyte may occur, which lowers the reliability of the all-solid-state battery.

[0006] To solve these problems, amorphous materials such as Li2O-B2O3-SiO2-P2O5 with low sintering temperature or oxynitride-based materials such as LIPON are being introduced as solid electrolyte materials, but these materials have very low ionic conductivity, so there are limitations in obtaining an all-solid-state battery with the required performance.

[0007] Therefore, there is a need to develop a solid electrolyte material that enables the production of high-performance all-solid-state batteries through a simple manufacturing process.

[0008] The inventors of the present invention have confirmed that when a solid electrolyte glass in which specific glass materials are combined is applied as a solid electrolyte material, high ionic conductivity is exhibited as crystallization (sintering) occurs even when sintering is performed at a relatively low temperature, and when this is applied to the manufacture of an all-solid-state battery, an all-solid-state battery with excellent performance can be manufactured through a simple process.

[0009] Accordingly, the object of the present invention is to provide a novel solid electrolyte glass and a method for manufacturing the same.

[0010] In addition, another object of the present invention is to provide an all-solid-state battery using the solid electrolyte glass and a method for manufacturing the same.

[0011] To solve the above problem, the present invention provides a solid electrolyte glass comprising a core portion including first glass particles; and a composite particle including a coating portion bonded to the surface of the core portion and formed by second glass particles, wherein the softening point of the second glass particles is lower than the softening point of the first glass particles.

[0012] In addition, the present invention provides a method for producing the solid electrolyte glass, comprising: (1) a step of producing a first glass particle from a first glass raw material; (2) a step of producing a second glass particle from a second glass raw material; and (3) a step of coating the second glass particle on the first glass particle to produce a composite particle including a core portion including the first glass particle and a coating portion formed by the second glass particle.

[0013] In addition, the present invention provides an all-solid-state battery comprising a positive electrode; a negative electrode; and a solid electrolyte, wherein the solid electrolyte comprises a sintered body of the solid electrolyte glass.

[0014] In addition, the present invention provides a method for manufacturing an all-solid-state battery, comprising the steps of respectively preparing a positive electrode material, a negative electrode material, and a solid electrolyte material; sequentially stacking and pressing the positive electrode material, the solid electrolyte material, and the negative electrode material to manufacture a structure; and sintering the structure, wherein the solid electrolyte material includes the solid electrolyte glass.

[0015] The solid electrolyte glass according to the present invention can exhibit high ionic conductivity by including a lithium chloroboracite-based material (crystalline material) when the cast core part undergoes heat treatment for sintering, and crystallization can occur at a low sintering temperature. Therefore, the solid electrolyte glass can be very advantageously introduced into the MLCB (Multi-Layer Ceramic Battery) process for manufacturing an all-solid-state battery by simultaneously laminating and sintering a cathode material / solid electrolyte material / cathode material, etc., thereby solving the problems of conventional electrode decomposition and interface reaction caused by high-temperature sintering.

[0016] In addition, the solid electrolyte glass according to the present invention has a large contact area with the active material due to the coating portion, which is mostly amorphous, and can exhibit high ionic conductivity. Therefore, by utilizing the solid electrolyte glass, the present invention can provide an all-solid-state battery with excellent performance.

[0017] In addition, the solid electrolyte glass according to the present invention is manufactured using glass particles that can be melted at 1,000°C or less, and thus the generation of hydrogen chloride (HCl Gas) generated during the melting and cooling stages during the manufacturing process can be reduced to 1 ppm / L or less.

[0018] In addition, the solid electrolyte glass according to the present invention enables the production of an all-solid-state battery with excellent performance even when various positive electrode active materials (e.g., high-capacity / high-voltage active materials including LCO) and / or negative electrode active materials (e.g., graphite, silicon) are applied, thereby ensuring material expandability.

[0019] Figure 1 is a schematic diagram showing a solid electrolyte glass and its sintered structure according to the present invention.

[0020] Figure 2 is a graph showing the results of differential thermal analysis (DTA) of the first glass particles and the second glass particles of Example 1 in Test Example 1.

[0021] Figure 3 is a graph showing the results of analyzing the change in amorphous / crystalline state of the first glass particle of Example 1 before and after sintering in Test Example 3 using XRD equipment.

[0022] Hereinafter, the present invention will be described in detail. Herein, the present invention is not limited to the contents described below, and may be modified in various forms as long as the gist of the invention is not changed.

[0023] The word "comprising" or "including" in this specification is intended to specify particular features, regions, steps, processes, elements and / or components, and does not exclude the presence or addition of other features, regions, steps, processes, elements and / or components, unless specifically stated to the contrary.

[0024] All numbers and expressions indicating the amounts of components, reaction conditions, etc. described in this specification can be understood to be modified by the term “about” in all cases unless otherwise specified.

[0025] In this specification, singular expressions include plural expressions unless the context clearly indicates otherwise.

[0026]

[0027] solid electrolyte glass

[0028] The solid electrolyte glass according to the present invention comprises powder particles (powder composite particles) in which specific glass materials are combined, and by controlling the components, crystallization temperature, and softening point of the glass materials, crystallization (sintering) is possible even when sintered at a low temperature (e.g., 510°C or lower), and has the characteristics of being able to exhibit high ionic conductivity.

[0029] Specifically, the solid electrolyte glass according to the present invention comprises a composite particle comprising a core portion including first glass particles; and a coating portion bonded to the surface of the core portion and formed by second glass particles, wherein the softening point of the second glass particles is lower than the softening point of the first glass particles. The solid electrolyte glass according to the present invention may optionally further include powdered glass particles.

[0030] Hereinafter, the solid electrolyte glass according to the present invention will be described with reference to FIG. 1.

[0031]

[0032] composite particles

[0033] The composite particles (10) included in the solid electrolyte glass according to the present invention include a core portion (11) and a coating portion (12). When a solid electrolyte is manufactured by sintering an aggregate of a large number of the composite particles (10), a ceramic solid electrolyte exhibiting high ionic conductivity while being able to dissolve lithium (Li) ions to the maximum extent possible can be obtained.

[0034] The core portion (11) included in the above composite particle (10) includes first glass particles. The first glass particles may have an amorphous state, a crystalline state, or a combination thereof, and their crystallinity may change through sintering. Specifically, the first glass particles may be converted from an amorphous state to a crystalline state during sintering, or may maintain a crystalline state as is.

[0035] According to the present invention, the first glass particle may have a crystallization temperature (Tc1) of 720°C or less. Specifically, the crystallization temperature (crystallization temperature of the material forming the first glass particle) (Tc1) of the first glass particle may be 715°C or less, 650°C or less, 600°C or less, 550°C or less, 520°C or less, 500°C or less, 480°C or less, or 470°C or less. For example, the crystallization temperature (Tc1) of the first glass particle may be, but is not limited to, 460 to 720°C, 460 to 600°C, 465 to 520°C, 470 to 500°C, 475 to 490°C, or 700 to 715°C. Since the crystallization temperature (Tc1) of the first glass particle is within the above range, a solid electrolyte with high ionic conductivity can be obtained through low-temperature sintering.

[0036] In addition, the first glass particle may have a softening point (Ts1) of 470 to 740°C, 475 to 700°C, 480 to 600°C, 485 to 520°C, 515 to 535°C, or 725 to 735°C. At this time, the softening point (Ts1) of the first glass particle is higher than the softening point (Ts2) of the second glass particle forming the coating portion (Ts1>Ts2), and thus, the ionic conductivity of the composite particle (10) and the solid electrolyte which is the sintered body thereof can be secured, which will be described later.

[0037] The first glass particle may include an oxide-based material having a network structure formed through a combination of components including lithium (Li), silicon (Si), boron (B), aluminum (Al), etc., and oxygen (O). Specifically, the first glass particle has a material in which a certain amount of chlorine (Cl) is positioned (substituted) in the oxygen (O) site that connects the cationic metal component into a network structure, and when crystallization occurs through heat treatment for sintering, the material may be converted into a lithium chloroboracite-based material. The lithium chloroboracite-based material is Li4B7O, which is formed into a crystal at a low temperature (e.g., 470 to 530° C.). 12 Cl, Li4Al3B4O 12 Cl, or Li4Al2B5O 12 It may be Cl. When the first glass particles are crystallized through heat treatment for sintering in this way, the core part (11) includes the lithium chloroborate-based material, and thus a solid electrolyte exhibiting high ionic conductivity can be provided. The core part (11) including the first glass particles may include the lithium chloroborate-based material at 85% by volume or more (e.g., 90 to 100% by volume) based on the total volume of the core part (11) after sintering. The sintering may be performed at 750°C or less, 720°C or less, 650°C or less, 600°C or less, 550°C or less, or 510°C or less.

[0038] Meanwhile, the first glass particles may further include oxides such as P2O5, SiO2, GeO2, TiO2, ZrO2, etc., in an amount of 10 mol% or less (based on the total mole number of the first glass particles) in addition to the main components such as lithium (Li), aluminum (Al), boron (B), oxygen (O), and chlorine (Cl) to improve crystallinity and ionic conductivity and lower the softening point.

[0039] For example, the first glass particle may include at least one selected from the group consisting of lithium (Li), aluminum (Al), boron (B), oxygen (O), and chlorine (Cl), and optionally, may further include at least one oxide selected from the group consisting of P2O5, SiO2, GeO2, TiO2, and ZrO2. Specifically, the first glass particle basically has a composition of Li2O-LiCl-Al2O3-B2O3, and additionally includes P2O5, SiO2, GeO2, TiO2, and / or ZrO2, thereby controlling the softening point, crystallization temperature, crystal phase, crystallinity, or ionic conductivity to be high or low.

[0040] According to the present invention, the first glass particles have an average particle diameter (D 50 ) may be 1 to 10 μm. Specifically, the average particle diameter (D) of the first glass particles 50 ) may be 1 to 8 ㎛, 1 to 7 ㎛, 1.5 to 5 ㎛, 2 to 4 ㎛, 2 to 3 ㎛, or 1 to 2 ㎛, but is not limited thereto. The average particle diameter (D of the first glass particles 50 ) is within the above range, the size of the first glass particles is secured so that a coating portion (12) having a uniform thickness can be formed, and the bonding (sintering) of the composite particles (10) is optimized, thereby providing a solid electrolyte with excellent properties.

[0041] The ionic conductivity of the above first glass particle is 0.1×10 -5 S / cm or more, 0.15×10 -5 S / cm or more, 0.3×10 -5 S / cm or more, 0.5×10 -5 S / cm or more, 1×10 -5 S / cm or more, 1×10 -4 S / cm or more, or 1×10 -3 It may be S / cm or more, but is not limited to this.

[0042] The core portion (10) including these first glass particles can be converted from an amorphous state to a crystalline state through sintering (e.g., sintering at 510°C or lower) and thus have a crystalline state. In addition, since the first glass particles already have a crystalline state, they can mostly maintain the crystalline state during sintering.

[0043] Meanwhile, the coating portion (12) included in the composite particle (10) is bonded to the surface of the core portion (11) and is formed by a second glass particle having an amorphous or crystalline state. By virtue of this coating portion (12), the solid electrolyte, which is a sintered body of the composite particle (10) (composite particles), exhibits high ionic conductivity, thereby preventing the generation of adsorbed water. Specifically, when sintering at low temperatures, the core portion (11) including the first glass particles does not undergo complete sintering at low temperatures (e.g., 510°C or lower) depending on the composition / particle size, and thus a solid electrolyte manufactured solely from the first glass particles of the core portion (11) may not exhibit 100% ionic conductivity characteristics. However, when the coating portion (12) formed by the second glass particles is bonded to the surface of the first glass particles, the glass component (e.g., amorphous glass component) constituting the coating portion (12) can assist in complete sintering while forming a closer contact point / contact surface with the positive electrode active material and / or the negative electrode active material, thereby providing a solid electrolyte exhibiting high ionic conductivity characteristics. In addition, when the first glass particle of the core portion (11) contains a large amount of chlorine (Cl) component, the chlorine (Cl) component reacts with moisture in the air to generate adsorbed water, but since the coating portion (12) is formed on the surface of the core portion (11), the chlorine (Cl) component is prevented from reacting with moisture, thereby preventing the generation of adsorbed water.

[0044] According to the present invention, the softening point (Ts2) of the second glass particles is lower than the softening point (Ts1) of the first glass particles (Ts1>Ts2), and accordingly, the sinterability of the composite particles (10) is secured, thereby providing a solid electrolyte exhibiting high ionic conductivity. That is, during the sintering process of the composite particles (10), the core portion (11) including the first glass particles undergoes crystallization or maintains crystalline properties, and the coating portion (12) including the second glass particles having a lower softening point (Ts) than the first glass particles has fluidity (softening) that allows stable bonding of the composite particles (10) (between the composite particles) without crystallization, thereby obtaining a solid electrolyte having high ionic conductivity while ensuring the sinterability of the composite particles (10). In addition, the contact point / contact surface with the positive electrode active material and / or negative electrode active material is expanded by the coating portion (12) including the second glass particle during the manufacture of the all-solid-state battery, so that the bonding stability with each active material can be secured.

[0045] Meanwhile, the coating portion (12) including the second glass particles is mostly amorphous after heat treatment for sintering, but may have a crystalline state in some portion. Specifically, the coating portion (12) formed by the second glass particles may be mostly amorphous and thus have an amorphous state when sintered at a low temperature (e.g., 510° C. or lower), or may have both amorphous and crystalline states due to some crystallization, or may have a crystalline state due to mostly crystallization. For example, the second glass particles may have an amorphous or crystalline state through sintering.

[0046] According to the present invention, the second glass particles may have a softening point (Ts2) of 460°C or higher. Specifically, the softening point (Ts2) of the second glass particles may be, but is not limited to, 460 to 740°C, 465 to 600°C, 470 to 550°C, 475 to 500°C, 480 to 495°C, or 500 to 535°C.

[0047] In addition, the second glass particles may have a crystallization temperature (Tc2) of 470°C or higher, considering sinterability and ionic conductivity. Specifically, the crystallization temperature (Tc2) of the second glass particles may be, but is not limited to, 475 to 720°C, 480 to 600°C, 520 to 580°C, 530 to 550°C, 470 to 500°C, or 475 to 495°C.

[0048] In addition to the main components such as lithium (Li), aluminum (Al), boron (B), oxygen (O), and chlorine (Cl), the second glass particles may further include oxides such as P2O5, SiO2, GeO2, TiO2, and ZrO2 at 10 mol% or less (based on the total mole number of the second glass particles) to improve crystallinity and ionic conductivity and lower the softening point.

[0049] For example, the second glass particle includes at least one selected from the group consisting of lithium (Li), aluminum (Al), boron (B), oxygen (O), and chlorine (Cl), and optionally may further include at least one oxide selected from the group consisting of P2O5, SiO2, GeO2, TiO2, and ZrO2. Specifically, the second glass particle basically has a composition of Li2O-LiCl-Al2O3-B2O3, and additionally includes P2O5, SiO2, GeO2, TiO2, and / or ZrO2, thereby controlling the softening point, crystallization temperature, crystal phase, crystallinity, or ionic conductivity to be high or low.

[0050] These second glass particles have an average particle diameter (D 50 ) may be 0.005 to 2 ㎛. Specifically, the average particle diameter (D) of the second glass particles 50 ) may be 0.01 to 2 ㎛, 0.05 to 2 ㎛, 0.1 to 1.5 ㎛, 0.3 to 1 ㎛, 0.5 to 0.7 ㎛, or 0.01 to 0.1 ㎛, but is not limited thereto. The average particle diameter (D of the second glass particles 50 ) is within the above range, it is possible to form a coating portion (12) having a uniform thickness, and to ensure good bonding of composite particles (10) (composite particles) during the sintering process.

[0051] In addition, the ionic conductivity of the second glass particle is 0.2×10 -6 S / cm or more, 0.2×10 -5 S / cm or more, 0.1×10 -5 S / cm or more, 0.5×10 -5 S / cm or more, 1×10 -5 S / cm or more, 1×10 -4 S / cm or more, or 1×10 -3 It may be S / cm or more, but is not limited to this.

[0052] According to the present invention, the difference (Ts1-Ts2) between the softening point (Ts1) of the first glass particle and the softening point (Ts2) of the second glass particle may be 10 to 220°C. Specifically, the temperature difference (Ts1-Ts2) of the softening points may be 15 to 210°C, 20 to 205°C, 25 to 200°C, 20 to 40°C, or 210 to 220°C, but is not limited thereto. Since the temperature difference (Ts1-Ts2) of the softening points is within the above range, a solid electrolyte having high ionic conductivity can be obtained through low-temperature sintering.

[0053]

[0054] Powdered glass particles

[0055] The powdered glass particles (20) further included in the solid electrolyte glass according to the present invention serve to increase the sinterability of the solid electrolyte glass. That is, when sintering is performed to bond the composite particles (10) included in the solid electrolyte glass to each other, the powdered glass particles (20) exhibit fluidity (softening) and serve as a sintering aid, thereby improving the sinterability of the solid electrolyte glass.

[0056] These powdered glass particles (20) have the same composition, physical properties, or average particle diameter (D) as the second glass particles for forming the coating portion (12). 50 ) may be different or the same. Preferably, considering the properties of the solid electrolyte, the powdered glass particles (20) may have the same components and properties as the second glass particles forming the coating portion (12).

[0057] Specifically, the softening point (Ts3) of the powdered glass particles (20) may be lower than the softening point (Ts1) of the first glass particles. For example, the softening point (Ts3) of the powdered glass particles (20) may be, but is not limited to, 460 to 740°C, 465 to 600°C, 470 to 550°C, 475 to 500°C, 480 to 495°C, or 500 to 535°C.

[0058] In addition, the above powdered glass particles (20) may have a crystallization temperature (Tc3) of 470°C or higher, specifically, 475 to 720°C, 480 to 600°C, 520 to 580°C, 530 to 550°C, 470 to 500°C, or 475 to 495°C, but is not limited thereto.

[0059] These powdered glass particles (20) have an average particle diameter (D 50 ) may be 0.005 to 2 ㎛. Specifically, the average particle diameter (D) of the powdered glass particles (20) 50) may be, but is not limited to, 0.01 to 2 μm, 0.05 to 2 μm, 0.1 to 1.5 μm, 0.3 to 1 μm, 0.5 to 0.7 μm, or 0.01 to 0.1 μm.

[0060] In addition, the ionic conductivity of the powdered glass particles is 0.2×10 -6 S / cm or more, 0.2×10 -5 S / cm or more, 0.1×10 -5 S / cm or more, 0.5×10 -5 S / cm or more, 1×10 -5 S / cm or more, 1×10 -4 S / cm or more, or 1×10 -3 It may be S / cm or more, but is not limited to this.

[0061] According to the present invention, the content of the powdered glass particles (20) may be 10 to 33 parts by weight based on 100 parts by weight of the composite particles. Specifically, the content of the powdered glass particles (20) may be 10 to 30 parts by weight, 10 to 25 parts by weight, 10 to 20 parts by weight, or 10 to 15 parts by weight based on 100 parts by weight of the composite particles, but is not limited thereto. When the content of the powdered glass particles (20) is within the above range, the sinterability of the composite particles (10) can be increased while ensuring the ionic conductivity of the solid electrolyte.

[0062]

[0063] According to the present invention, the solid electrolyte glass including the composite particles (10) may have a sintering temperature for crystallization of 750°C or less, 720°C or less, 650°C or less, 600°C or less, 550°C or less, or 510°C or less. Specifically, the sintering temperature of the solid electrolyte glass (e.g., an aggregate of composite particles (10)) may be 505°C or less, 500°C or less, 495°C or less, 490°C or less, 485°C or less, or 480°C or less (e.g., 465 to 730°C, 470 to 510°C, 470 to 505°C, 470 to 500°C, 475 to 498°C, 480 to 495°C, or 485 to 490°C), but is not limited thereto. As the sintering temperature is within the above range, crystallization of the solid electrolyte glass is secured, thereby stably forming a solid electrolyte (sintered body of the solid electrolyte glass) having high ionic conductivity, while preventing electrode decomposition and interface reactions from occurring during the manufacturing process of the all-solid-state battery.

[0064] According to the present invention, the solid electrolyte glass has an ionic conductivity of 0.26×10 -5 S / cm or more. Specifically, the ionic conductivity of the solid electrolyte glass is 0.3×10 -5 S / cm or more, 0.5×10 -5 S / cm or more, 1×10 -5 S / cm or more, 1×10 -4 S / cm or more, or 1×10 -3 It may be S / cm or more (e.g., 0.000003 to 2 S / cm, or 0.000005 to 1.5 S / cm).

[0065] In this way, the solid electrolyte glass of the present invention including composite particles or composite particles and powdery glass particles can be converted into a sintered body through a sintering process at a low temperature (e.g., 510°C or lower), and the converted sintered body exhibits high ionic conductivity and can solidify a large amount of lithium ions. In addition, the coating portion of the composite particles and the powdery glass particles are softened during the sintering process, thereby obtaining a sintered body with a large specific surface area, and thereby, it is possible to expand the contact point / contact surface of the sintered body with the positive electrode active material and / or the negative electrode active material.

[0066] Therefore, the solid electrolyte glass according to the present invention can be effectively applied as a solid electrolyte material of an all-solid-state battery.

[0067]

[0068] Method for manufacturing solid electrolyte glass

[0069] The method for manufacturing a solid electrolyte glass according to the present invention is a method for manufacturing the above-described solid electrolyte glass. Specifically, the method for manufacturing a solid electrolyte glass according to the present invention comprises: (1) a step of manufacturing first glass particles from a first glass raw material; (2) a step of manufacturing second glass particles from a second glass raw material; and (3) a step of coating the second glass particles on the first glass particles to manufacture composite particles including a core portion including the first glass particles and a coating portion formed by the second glass particles. The method for manufacturing a solid electrolyte glass according to the present invention may optionally further comprise a step of (4) additionally mixing powdered glass particles into the composite particles.

[0070] Hereinafter, a method for manufacturing a solid electrolyte glass according to the present invention will be described.

[0071]

[0072] (1) Manufacturing of first glass particles

[0073] According to the present invention, step (1) is a step of manufacturing first glass particles for forming a core portion using a first glass raw material.

[0074] The above first glass raw material can be prepared by going through a process of weighing and mixing each raw material component in a predetermined amount to obtain first glass particles having a desired composition.

[0075] According to the present invention, the production of the first glass particles can be performed through melting, cooling, and crushing (1-1) of the first glass raw material; liquid synthesis (1-2) of the first glass raw material; or solid synthesis (1-3) of the first glass raw material.

[0076] Melting, cooling and crushing (1-1) of the above first glass raw material can be performed through the following process.

[0077] Specifically, the prepared first glass raw material is melted and cooled to produce a cullet. For example, the first glass raw material is melted at a temperature of 1,000°C or lower to obtain a melt, and the obtained melt is cooled (quenched) by a conventionally known method to obtain a cullet (e.g., an amorphous or crystalline cullet).

[0078] The melting of the first glass raw material may be performed in a platinum crucible or a crucible that can withstand a thermal shock of 1,000°C or higher, and at this time, the melting temperature may be specifically, but is not limited to, 930 to 1,000°C, 950 to 995°C, or 960 to 990°C.

[0079] Next, the obtained cullet may be pulverized to produce first glass particles (glass powder for the core portion, or glass frits for the core portion). The pulverization may be performed using a conventionally known pulverizer, and the pulverization conditions may be set according to the size of the desired first glass particles. Specifically, the pulverization may be performed by first performing coarse pulverization and then performing fine pulverization. For example, the powder obtained through the first coarse pulverization may be classified into 60 mesh (250 ㎛ or less), and then the second fine pulverization may be performed.

[0080] The liquid synthesis (1-2) of the above first glass raw material means manufacturing first glass particles using the liquid first glass raw material, and can be performed by the following process.

[0081] Specifically, the prepared first glass raw material is synthesized in a liquid state to produce a precipitate. For example, a mantle and a flask capable of maintaining a temperature of 130 to 160°C are placed and set inside an argon atmosphere glove box, the prepared liquid first glass raw material (liquid precursor raw material) is placed in the flask together with a magnetic bar, and the resulting precipitate-containing solution is cooled to room temperature to obtain a precipitate. Subsequently, the precipitate is washed several times with a solvent such as ethanol and then dried to produce first glass particles.

[0082] The solid-state synthesis (1-3) of the above first glass raw material means manufacturing first glass particles using the solid-state first glass raw material, and can be performed by the following process.

[0083] Specifically, the prepared first glass raw material is subjected to solid-phase synthesis to produce a powder. For example, the prepared solid first glass raw material (solid precursor raw material) is placed in a ball mill, a solvent is added, wet-mixed for 4 hours or more, and the resulting mixture is dried at high temperature to obtain a powder. Subsequently, the powder is heat-treated and pulverized to produce first glass particles.

[0084] As the first glass particles are manufactured through melting, cooling and grinding; liquid synthesis; or solid synthesis, the first glass particles may have a particle size suitable for forming a core portion. For example, the first glass particles may have an average particle diameter (D 50 ) may be 1 to 10 μm (specifically, 1 to 8 μm, 1 to 7 μm, 1.5 to 5 μm, 2 to 4 μm, 2 to 3 μm, or 1 to 2 μm).

[0085]

[0086] (2) Manufacturing of second glass particles

[0087] According to the present invention, step (2) is a step of manufacturing second glass particles for forming a coating portion using a second glass raw material.

[0088] The above second glass raw material can be prepared by going through a process of weighing and mixing each raw material component in a predetermined amount to obtain second glass particles having a desired composition.

[0089] According to the present invention, the production of the second glass particles can be performed through melting, cooling, and crushing (2-1) of the second glass raw material; liquid synthesis (2-2) of the second glass raw material; or solid synthesis (2-3) of the second glass raw material.

[0090] Melting, cooling and crushing (2-1) of the above second glass raw material can be performed through the following process.

[0091] Specifically, the prepared second glass raw material is melted and cooled to produce a cullet. For example, the second glass raw material is melted at a temperature of 1,000°C or lower to obtain a melt, and the obtained melt is cooled (quenched) by a conventionally known method to obtain a cullet (e.g., an amorphous or crystalline cullet).

[0092] The melting of the second glass raw material may be performed in a platinum crucible or a crucible that can withstand a thermal shock of 1,000°C or higher, and at this time, the melting temperature may be specifically, but is not limited to, 930 to 1,000°C, 950 to 995°C, or 960 to 990°C.

[0093] Next, the obtained cullet may be pulverized to produce second glass particles (glass powder for the coating portion, or glass frits for the coating portion). The pulverization may be performed using a conventionally known pulverizer, and the pulverization conditions may be set according to the size of the desired second glass particles. Specifically, the pulverization may be performed by first performing coarse pulverization and then second performing fine pulverization. For example, the powder obtained through the first coarse pulverization may be classified into 60 mesh (250 ㎛ or less), and then the second fine pulverization may be performed.

[0094] The liquid synthesis (2-2) of the above second glass raw material means manufacturing second glass particles using the liquid second glass raw material, and can be performed through the following process.

[0095] Specifically, the prepared second glass raw material is synthesized in a liquid state to produce a precipitate. For example, a mantle and a flask capable of maintaining a temperature of 130 to 160°C are placed and set inside an argon atmosphere glove box, the prepared liquid second glass raw material (liquid precursor raw material) is placed in the flask together with a magnetic bar, and the resulting precipitate-containing solution is cooled to room temperature to obtain a precipitate. Subsequently, the precipitate is washed several times with a solvent such as ethanol and then dried to produce second glass particles.

[0096] The solid-state synthesis (2-3) of the above second glass raw material means manufacturing second glass particles using the solid-state second glass raw material, and can be performed through the following process.

[0097] Specifically, the prepared second glass raw material is subjected to solid-phase synthesis to produce a powder. For example, the prepared solid second glass raw material (solid precursor raw material) is placed in a ball mill, a solvent is added, wet-mixed for 4 hours or more, and the resulting mixture is dried at high temperature to obtain a powder. Subsequently, the powder is heat-treated and pulverized to produce second glass particles.

[0098] By manufacturing the second glass particles through melting, cooling and grinding; liquid synthesis; or solid synthesis, the second glass particles can have an optimized particle size that can be uniformly and strongly bonded to the surface of the first glass particles. For example, the second glass particles may have an average particle diameter (D 50 ) may be 0.005 to 2 μm (specifically, 0.01 to 2 μm, 0.05 to 2 μm, 0.1 to 1.5 μm, 0.1 to 1 μm, 0.5 to 0.7 μm, or 0.01 to 0.1 μm).

[0099]

[0100] (3) Manufacturing of composite particles

[0101] According to the present invention, step (3) is a step of manufacturing a composite particle including a core portion including the first glass particle and a coating portion formed by the second glass particle by coating the second glass particle manufactured in step (2) on the first glass particle manufactured in step (1).

[0102] The coating of the second glass particles can be achieved through physical mixing with stirring for 2 hours or more. Here, in order to ensure that the coating of the second glass particles is smoothly achieved through physical mixing, when mixing the first glass particles and the second glass particles, a small amount of a polymer binder (e.g., an acrylic resin binder) that decomposes and is completely removed at a temperature of 200 to 350° C. can be added, thereby enhancing the coating power of the second glass particles.

[0103]

[0104] (4) Addition of powdered glass particles

[0105] According to the present invention, step (4) is a step of additionally mixing powdered glass particles into the composite particles manufactured in step (3).

[0106] The above mixing can be performed by a conventionally known method, and at this time, the content of the powdered glass particles to be additionally mixed can be 10 to 33 parts by weight (specifically, 10 to 30 parts by weight, 10 to 25 parts by weight, 10 to 20 parts by weight, or 10 to 15 parts by weight) with respect to 100 parts by weight of the composite particles.

[0107] As the above powdered glass particles are added and mixed with the composite particles, the sinterability of the solid electrolyte glass including these mixed particles can be improved.

[0108] The above powdered glass particles can be manufactured through the same method as the first glass particles or the second glass particles, and their composition can be the same as the second glass particles.

[0109]

[0110] All-solid-state batteries

[0111] The all-solid-state battery (specifically, a laminated all-solid-state battery for substrate mounting) according to the present invention comprises a positive electrode; a negative electrode; and a solid electrolyte, and may be an ultra-small battery mounted on a substrate and used. The manufacturing process thereof requires low-temperature sintering because it applies the same process as a conventional MLCB (Multi-layer Ceramic Battery).

[0112] A detailed description of these all-solid-state batteries is as follows.

[0113] The positive electrode included in the all-solid-state battery according to the present invention may include at least one selected from the group consisting of a positive electrode current collector, a positive electrode active material, a conductive material, and a binder.

[0114] The above-mentioned positive electrode current collector may be a conventionally known electrically conductive plate-shaped substrate (thin plate). Specifically, the above-mentioned positive electrode current collector may be an aluminum substrate, a stainless steel (SUS) substrate, a nickel substrate, an iron substrate, or a carbon substrate.

[0115] The above positive electrode active material may include a commonly known oxide active material or a sulfide active material. Specifically, the oxide active material may include LiCoO2, LiMnO2, LiNiO2, LiVO2, Li 1+x Ni 1 / 3 Co 1 / 3 Mn 1 / 3 O2, LiMn2O4, Li(Ni 0.5 Mn 1.5 )O4, LiNiVO4, LiCoVO4, LiFePO4, LiMnPO4, LiCoPO4, LiNiPO4, Li2FeSiO4, Li2MnSiO4, LiNi 0.8 Co0.2-x Al x O2, Li 1+x Mn 2-x-y M y O4 (M is at least one of Al, Mg, Co, Fe, Ni, and Zn, and 0<x+y<2) and Li4Ti5O 12 It may be at least one selected from the group consisting of, but is not limited thereto. In addition, the sulfide active material may be at least one selected from the group consisting of, but is not limited thereto.

[0116] The above-mentioned conductive material may specifically include at least one selected from the group consisting of CNT (Carbon nanotube), carbon black, conducting graphite, ethylene black, and graphene, but is not limited thereto.

[0117] The above binder may include at least one selected from the group consisting of BR (Butadiene rubber), NBR (Nitrile butadiene rubber), HNBR (Hydrogenated nitrile butadiene rubber), PVDF (polyvinylidene difluoride), PTFE (polytetrafluoroethylene), CMC (carboxymethylcellulose), and PEO (Polyethylene oxide), but is not limited thereto.

[0118] The negative electrode included in the all-solid-state battery according to the present invention may include at least one selected from the group consisting of a negative electrode current collector, a negative electrode active material, a conductive material, and a binder.

[0119] The above-described negative electrode current collector may be a conventionally known electrically conductive plate-shaped substrate (thin plate). Specifically, the above-described negative electrode current collector may be a copper substrate, a nickel substrate, a stainless steel (SUS) substrate, or a carbon substrate.

[0120] The above negative electrode active material may include a commonly known carbon-based material, lithium-based material, silicon-based material, or metal-based material. Specifically, the above negative electrode active material may include a silicon material (SiOx, SiC), graphite-based carbon, Li x Fe2O3(0≤x≤1), Li x WO2(0≤x≤1), Sn x Me 1-x Me' y O z (Me: Mn,Fe,Pb,Ge; Me': Al, B, P, Si, elements of group 1, 2, and 3 of the periodic table, halogens; 0 <x≤1; 1≤y≤3; 1≤z≤8), 리튬 금속 산화물, 불화리튬, 탄산리튬, 수산화리튬, SnO, SnO2, PbO, PbO2, Pb2O3, Pb3O4, Sb2O3, Sb2O4, Sb2O5, GeO, GeO2, Bi2O3, Bi2O4, Bi2O5, LiCo-Ni계 물질 및 티타늄 산화물로 이루어진 군에서 선택된 1종 이상일 수 있으나, 이에 한정되는 것은 아니다.

[0121] The above-mentioned conductive material may specifically include at least one selected from the group consisting of CNT (Carbon nanotube), carbon black, conducting graphite, ethylene black, and graphene, but is not limited thereto.

[0122] The above binder may include, but is not limited to, an acrylic binder, an ethyl cellulose (EC) binder, or a combination thereof.

[0123] The solid electrolyte included in the all-solid-state battery according to the present invention includes a sintered body of the above-described solid electrolyte glass. Specifically, the solid electrolyte may include a sintered body obtained by sintering a solid electrolyte glass material including the above-described solid electrolyte glass at a low temperature (e.g., 510°C or lower, or 500°C or lower). Since the solid electrolyte includes a sintered body formed from the above-described solid electrolyte glass, it exhibits high ionic conductivity and enables efficient movement of lithium ions. Therefore, the present invention can provide an all-solid-state battery with excellent performance.

[0124] The all-solid-state battery comprising the solid electrolyte according to the present invention has a significantly lower risk of fire compared to a LIB secondary battery using a liquid electrolyte, i.e., LIB solution, and can be used with electrode materials having high voltage and high capacity. In particular, when the solid electrolyte is laminated simultaneously with the electrode at a low temperature (e.g., below 510°C) using the MLCB process, the process cost is very low, making it advantageous for mass production. In addition, since it can have various battery shapes, it can be advantageous for the implementation of ultra-small batteries.

[0125]

[0126] Manufacturing method of all-solid-state battery

[0127] The method for manufacturing an all-solid-state battery according to the present invention comprises: (A) a step of preparing a positive electrode material, a negative electrode material, and a solid electrolyte material, respectively; (B) a step of sequentially laminating and pressurizing the positive electrode material, the solid electrolyte material, and the negative electrode material to manufacture a structure; and (C) a step of sintering the structure.

[0128] The method for manufacturing an all-solid-state battery according to the present invention is characterized by corresponding to a multi-layer ceramic battery (MLCB) process, which allows for easy manufacturing of an ultra-small all-solid-state battery with excellent performance through a simple manufacturing process. Specifically, when manufacturing an all-solid-state battery including a positive electrode, a solid electrolyte, and a negative electrode by simultaneously laminating each material and heat-treating at a low sintering temperature (e.g., 510°C or lower), the first glass particle component of the core portion of the composite particle included in the solid electrolyte glass in the solid electrolyte material is crystallized, and the second glass particle component used for coating and mixing is softened to expand the contact point / contact surface with the positive electrode active material / negative electrode active material, and sintering is performed in a state where pores are minimized, so that an all-solid-state battery including a solid electrolyte with high ionic conductivity can be manufactured.

[0129] Hereinafter, a method for manufacturing an all-solid-state battery according to the present invention will be described in detail as follows.

[0130]

[0131] (A) Preparation of each material

[0132] According to the present invention, step (A) is a step of preparing a positive electrode material, a negative electrode material, and a solid electrolyte material, respectively.

[0133] The above-described positive electrode material may include at least one selected from the group consisting of a positive electrode current collector, a positive electrode active material, a conductive material, and a binder included in the above-described positive electrode. Specifically, the positive electrode material may be prepared by mixing the positive electrode active material, the conductive material, and the binder in a predetermined ratio to prepare a positive electrode slurry, and applying the same to the positive electrode current collector.

[0134] The above-described negative electrode material may include at least one selected from the group consisting of a negative electrode current collector, a negative electrode active material, a conductive material, and a binder included in the above-described negative electrode. Specifically, the negative electrode material may be prepared by mixing the negative electrode active material, the conductive material, and the binder in a predetermined ratio to prepare a negative electrode slurry, and applying the same to the negative electrode current collector.

[0135] The above-described solid electrolyte material may include the above-described solid electrolyte glass. Specifically, the above-described solid electrolyte material may further include a commonly known solvent (methylpyrrolidone, ethanol, isopropanol, water, etc.) and a binder (e.g., PVDF, CMC, PEO, etc.) together with the above-described solid electrolyte glass, and may be prepared in a slurry state through a process of mixing these.

[0136] The above slurry-state solid electrolyte material can minimize pores in the slurry state by including the solid electrolyte glass, thereby preventing a decrease in ionic conductivity due to the presence of pores in the slurry state.

[0137]

[0138] (B) Manufacturing of laminated structures

[0139] According to the present invention, step (B) is a step of manufacturing a structure by sequentially stacking and pressing the positive electrode material, the solid electrolyte material, and the negative electrode material prepared in step (A), respectively. The stacking of each material may be performed one or more times, and thus the structure may have a stacked structure of positive electrode material / solid electrolyte material / negative electrode material, or a stacked structure in which the structure is repeated (e.g., a stacked structure of positive electrode material / solid electrolyte material / negative electrode material / positive electrode material / solid electrolyte material / negative electrode material).

[0140] A commonly known method can be applied to the method of laminating each of the above materials, and then pressurization can be performed under conditions where each material can be combined to a required level to form a structure.

[0141]

[0142] (C) Sintering

[0143] According to the present invention, step (C) is a step of sintering the structure manufactured in step (B). Since the solid electrolyte material of the present invention includes a solid electrolyte glass that is well crystallized and bonded (bonded between particles) even when sintered at a low temperature, it is possible to sinter the structure at a low temperature, and thus, the conventional problems of electrode decomposition and interface reaction caused by high-temperature sintering are solved, and an all-solid-state battery with excellent performance and reliability can be manufactured.

[0144] Specifically, the sintering temperature of the structure may be 750°C or less, 720°C or less, 650°C or less, 600°C or less, 550°C or less, or 510°C or less. For example, the sintering temperature may be 505°C or less, 500°C or less, 495°C or less, 490°C or less, 485°C or less, or 480°C or less (specifically, 465 to 730°C, 470 to 510°C, 470 to 505°C, 470 to 500°C, 475 to 498°C, or 480 to 495°C, but is not limited thereto). As the sintering temperature is within the above range, crystallization of the solid electrolyte glass (specifically, the first glass particles included in the core portion) can be secured.

[0145]

[0146] The method for manufacturing an all-solid-state battery according to the present invention may additionally include a step of storing the sintered structure obtained through the above sintering inside a battery case and caulking it, thereby obtaining a commercialized all-solid-state battery.

[0147] The present invention is described in more detail through the following examples. However, the following examples are intended only to illustrate the present invention and are not intended to limit the scope of the present invention.

[0148]

[0149] <Manufacturing of solid electrolyte glass>

[0150] [Example 1]

[0151] (1) Manufacturing of first glass particles (melting / cooling / crushing)

[0152] a-1. The first glass raw material (glass raw material for core part) was prepared by mixing 26 mol% of Li2O, 39 mol% of B2O3, 16 mol% of Al2O3, and 19 mol% of LiCl.

[0153] b-1. The prepared first glass raw material was melted at 930 to 1,000°C to obtain a molten product, and the obtained molten product was poured into a water-cooled twin roller and cooled to produce a cullet.

[0154] c-1. After the first pulverization of the above cullet using a grinder mill, the second pulverization is performed using an attrition mill to obtain the average particle size (D 50 ) was used to produce the first glass particle having a size of 2 μm.

[0155] (2) Manufacturing of second glass particles (liquid synthesis)

[0156] a-2. Lithium acetate dihydrate (CH3COOLi·2H2O), copper(II) chloride dihydrate (CuCl2·2H2O), boric acid (H3BO3), aluminum nitrate nonahydrate (Al(NO3)3·9H2O), phosphorus(V) oxide chloride (PCl), and zirconyl chloride octahydrate (ZrOCl2·8H2O) were prepared as the second glass raw material (glass raw material for the coating part).

[0157] b-2. The prepared second glass raw material was placed in a flask containing a magnetic bar. Next, the flask was placed in an argon-atmosphere glove box equipped with a mantle, and stirred and reacted for more than 12 hours to obtain a solution containing a precipitate.

[0158] c-2. The obtained precipitate-containing solution is cooled to room temperature to obtain a precipitate, washed several times with ethanol, and dried to obtain the average particle size (D 50 ) produced second glass particles having a size of 0.1 ㎛ or less.

[0159] (3) Manufacturing of composite particles

[0160] Composite particles were manufactured by stirring the first glass particles and the second glass particles at room temperature for 2 hours or more to coat the second glass particles on the surface of the first glass particles.

[0161]

[0162] [Examples 2 to 4]

[0163] Composite particles were manufactured through the same process as Example 1, except that the first glass particles and the second glass particles having the compositions shown in Table 1 below were applied.

[0164]

[0165] [Example 5]

[0166] (1) Preparation of first glass particles (solid-state synthesis)

[0167] a-1. Lithium carbonate (Li2CO3), di-Boron trioxide (B2O3), aluminum oxide (Al2O3), and lithium chloride (LiCl) were prepared as the first glass raw material (glass raw material for core part).

[0168] b-1. The prepared first glass raw material was placed in an alumina pot (ball mill) containing zirconia balls, ethanol was added as a solvent, and ball milling was performed for more than 4 hours to prepare a uniform mixture. Subsequently, the obtained mixture was dried at 80°C for more than 12 hours to obtain a powder.

[0169] c-1. The obtained powder is heat treated at 500 to 700 ℃ for 4 hours or more to produce a crystallized powder, and then pulverized to obtain an average particle size (D 50 ) produced first glass particles having a size of 1 μm or less.

[0170] (2) Manufacturing of second glass particles (melting / cooling / crushing)

[0171] a-2. A second glass raw material (glass raw material for coating part) was prepared by mixing 26 mol% of Li2O, 38 mol% of B2O3, 18 mol% of Al2O3, and 18 mol% of LiCl.

[0172] b-2. The prepared second glass raw material was melted at 930 to 1,000°C to obtain a molten product, and the obtained molten product was poured into a water-cooled twin roller and cooled to produce a cullet.

[0173] c-2. After the above cullet is first crushed using a grinder mill, a second fine crushing is performed using an attrition mill to obtain the average particle size (D 50 ) produced a second glass particle having a size of 0.7 μm.

[0174] (3) Manufacturing of composite particles

[0175] Composite particles were manufactured by stirring the first glass particles and the second glass particles at room temperature for 2 hours or more to coat the second glass particles on the surface of the first glass particles.

[0176]

[0177] [Example 6]

[0178] Composite particles were manufactured through the same process as Example 5, except that the first glass particles and the second glass particles having the compositions shown in Table 1 below were applied.

[0179]

[0180] [Comparative Examples 1 and 2]

[0181] Single glass particles (particles without a coating) having the composition shown in Table 2 below were applied.

[0182]

[0183] [Example 1]

[0184] Differential thermal analysis (DTA) was performed on the first and second glass particles of the examples and the glass particles of the comparative examples at a heating rate of 10°C / min in the range from room temperature to 800°C to determine the glass transition temperature (Tg), crystallization temperature (Tc), crystallization start temperature (Tx), and softening point (Ts), respectively, and the results are shown in Table 1, Table 2, and Fig. 2 below.

[0185]

[0186] [Example 2]

[0187] The first glass particles, second glass particles, and composite particles of the examples and the glass particles of the comparative examples were heat treated in the range of 490 to 510°C for 1 hour to crystallize them, thereby manufacturing glasses (ceramics), and sputter-coated with Au on both surfaces of each manufactured glass to manufacture specimens. Thereafter, the ionic conductivity of each manufactured specimen was measured using an impedance device (Zivelab, MP2), and the results are shown in Tables 1 and 2 below.

[0188]

[0189] [Example 3]

[0190] For the first glass particle of Example 1, the amorphous state before sintering and the crystalline state (specifically, the crystal structure of lithium chloroborous site) after sintering at 490 to 510°C were confirmed using XRD equipment (Malvern Panalytical X'Pert3), and the results are shown in Fig. 3.

[0191]

[0192] Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 First glass particle (core) (mol%) Li2O2 6 26.4 27.5 27.5 26.7 B2O3 39 37.6 37.6 36.5 31.7 Al2O3 16 15.2 15.2 13.5 23.3 LiCl 19 20.1 18.7 21.3 18.3 ZrO2 + TiO2 - 0.3 0.3 - P2O5 + GeO2 + SiO2 + Others - 0.7 0.7 0.9 - Second Glass particles (coating part) (mol%) Li2O2 8.0 2627 B2O3 34.3 3837.5 Al2O3 8.2 1817 LiCl 18.8 1818.5 ZrO2 + TiO2 0.4 -- P2O5 + GeO2 + SiO2 + Others 10.3 -- First glass particle (℃) Tg 4 16 4 12 40 8 394 - Tc 4 8 3 4 7 6 4 7 3 4 6 8 7 1 3 Tx 4 7 0 4 6 2 4 6 0 4 5 2 7 0 2 Ts 5 3 0 5 3 0 5 2 0 5 2 0 7 3 0 Second glass particle (℃) Tg 4 18 4 16 4 1 3 Tc 5 4 8 4 8 9 4 7 9 Tx 5 3 2 4 7 6 4 6 6 Ts 4 9 5 5 3 0 5 3 0 First glass particle (10 -5 S / cm) Room temperature ionic conductivity 0.5 0.45 0.40 35 0.5 Second glass particle (10 -5 S / cm) Room temperature ionic conductivity 0.25 0.15 0.18 Composite particles (10 -5 S / cm) Room temperature ionic conductivity 0.38 0.35 0.30 28 0.33 0.37

[0193] Comparative Example 1 Comparative Example 2 First glass particle (mol%) Li2O2 3.4 34.78 B2O3 31.3 3.04 Al2O3 23.4-LiCl2 1.9 26.09 ZrO2+TiO2--P2O5+GeO2+SiO2+Others-6.09 Second glass particle (mol%) Li2O--B2O3--Al2O3--LiCl--ZrO2+TiO2--P2O5+GeO2+SiO2+Others--First glass particle (℃) Tg 4 26 356 Tc 5 30 485 Tx 5 17-Ts 5 50 or more-Second glass particle (℃) Tg--Tc--Tx--Ts--First glass particle (10 -5 S / cm) Room temperature ionic conductivity 0.20.25 Second glass particle (10 -5 S / cm) Room temperature ionic conductivity--composite particles (10 -5 S / cm) Room temperature ionic conductivity--

[0194] Referring to Table 1 above, it can be confirmed that Examples 1 to 6 according to the present invention have high ionic conductivity of the first glass particle and the second glass particle, and thus the composite particle in which they are combined exhibits high ionic conductivity compared to the glass particles of Comparative Examples 1 and 2, which are composed of glass particles alone.

[0195] In addition, referring to FIG. 2, it can be confirmed that in Example 1 according to the present invention, crystallization begins at a lower temperature than that of the second glass particles while satisfying the crystallization temperature of the first glass particles to be 520°C or lower (483.40°C).

[0196] Also, referring to FIG. 3, it can be confirmed that in Example 1 according to the present invention, the first glass particle maintains an amorphous state (see a of FIG. 3) and then, when sintering is performed at a low temperature of 510°C or lower, it is converted to a crystalline state (see b of FIG. 3). Through this, it can be seen that the present invention can implement a solid electrolyte glass capable of low-temperature sintering.

[0197] [Explanation of symbols]

[0198] 10: Composite particles

[0199] 11: Core

[0200] 12: Coating section

[0201] 20: Powdered glass particles

Claims

1. Comprising a composite particle comprising a core portion including first glass particles; and a coating portion bonded to the surface of the core portion and formed by second glass particles; A solid electrolyte glass, wherein the softening point of the second glass particles is lower than the softening point of the first glass particles.

2. In paragraph 1, A solid electrolyte glass having a crystallization temperature of the first glass particle of 720°C or lower.

3. In paragraph 1, A solid electrolyte glass having a softening point of the second glass particles of 460°C or higher.

4. In paragraph 1, A solid electrolyte glass, wherein the difference between the softening point of the first glass particle and the softening point of the second glass particle is 10 to 220°C.

5. In paragraph 1, The crystallization temperature of the first glass particle is 460 to 720°C, A solid electrolyte glass having a crystallization temperature of the second glass particles of 470°C or higher.

6. In paragraph 1, A solid electrolyte glass, wherein the core portion including the first glass particles comprises a lithium chloroboracite-based material through sintering.

7. In paragraph 1, A solid electrolyte glass in which the core portion including the first glass particles has a crystalline structure through sintering, and the coating portion has an amorphous structure or a crystalline structure.

8. In paragraph 1, The average particle diameter (D) of the first glass particles 50 ) is 1 to 10 μm, The average particle diameter (D) of the second glass particles 50 ) is 0.005 to 2 ㎛, solid electrolyte glass.

9. In paragraph 1, A solid electrolyte glass further comprising 10 to 33 parts by weight of powdered glass particles per 100 parts by weight of the composite particles.

10. In paragraph 1, A solid electrolyte glass having a sintering temperature for crystallization of 510°C or less.

11. In paragraph 1, Ionic conductivity is 0.26×10 -5 Solid electrolyte glass having a density of S / cm or more. 12.(1) A step of manufacturing first glass particles from a first glass raw material; (2) a step of manufacturing second glass particles from a second glass raw material; and (3) A method for producing a solid electrolyte glass according to claim 1, comprising a step of manufacturing a composite particle including a core portion including the first glass particle and a coating portion formed by the second glass particle by coating the first glass particle with the second glass particle.

13. In paragraph 12, A method for producing a solid electrolyte glass, wherein the production of the first glass particles is performed through melting, cooling, and crushing of the first glass raw material; liquid synthesis of the first glass raw material; or solid synthesis of the first glass raw material.

14. In paragraph 12, A method for producing a solid electrolyte glass, wherein the production of the second glass particles is performed through melting, cooling, and crushing of the second glass raw material; liquid synthesis of the second glass raw material; or solid synthesis of the second glass raw material.

15. In paragraph 12, (4) A method for manufacturing a solid electrolyte glass, further comprising a step of adding powdered glass particles to the above composite particles.

16. Containing a positive electrode; a negative electrode; and a solid electrolyte, An all-solid-state battery, wherein the solid electrolyte comprises a sintered body of the solid electrolyte glass of claim 1. 17.(A) Step of preparing a cathode material, a cathode material, and a solid electrolyte material, respectively; (B) a step of sequentially stacking and pressing the positive electrode material, the solid electrolyte material, and the negative electrode material to manufacture a structure; and (C) comprising a step of sintering the above structure, A method for manufacturing an all-solid-state battery, wherein the solid electrolyte material comprises the solid electrolyte glass of claim 1.

18. In paragraph 17, A method for manufacturing an all-solid-state battery, wherein sintering of the above structure is performed at 510°C or lower.

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