All-solid secondary battery pressure airtight device

Abstract

To provide an all-solid secondary battery pressure airtight device.SOLUTION: The present invention provides an all-solid secondary battery airtight device (1). In the secondary battery pressure airtight device (1), a secondary battery (9) is compressed under an isotropic pressure condition in a high-temperature pressurizing step for the secondary battery (9) by forming an internal space for transmitting a compression force to the secondary battery (9) while sealing the all-solid secondary battery (9) by absorbing one side in vacuum. The object of the present invention is to provide the all-solid secondary battery pressure airtight device, in which one side is vacuum-adsorbed to seal the all-solid secondary battery, and an internal space for transmitting a pressurizing force to the secondary battery is formed, so that the secondary battery is pressurized under the isotropic pressure condition during a high-temperature pressurizing process.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a pressurization and airtight device for all-solid-state secondary batteries. More specifically, an internal space is formed such that one side is vacuum-adsorbed to seal the all-solid-state secondary battery while transmitting a pressing force to the secondary battery, so that the secondary battery is pressurized under isotropic pressure conditions during the high-temperature pressurization process. The present invention relates to a pressurization and airtight device for all-solid-state secondary batteries.

Background Art

[0002] Recently, as the development of electric vehicles, energy storage batteries, robots, satellites, etc. has become full-scale, research on secondary batteries, which are high-performance batteries capable of repeated charge and discharge, has been actively conducted. Currently available commercial secondary batteries include nickel-cadmium batteries, nickel-metal hydride batteries, nickel-zinc batteries, lithium secondary batteries, etc. Among them, lithium secondary batteries have attracted attention due to the advantages that they hardly exhibit a memory effect compared to nickel-based secondary batteries, can be freely charged and discharged, have a very low self-discharge rate, and have a high energy density.

[0003] Such lithium secondary batteries mainly use a lithium-based oxide and a carbon material as a positive electrode active material and a negative electrode active material, respectively. A lithium secondary battery includes an electrode assembly in which a positive electrode plate and a negative electrode plate, each coated with a positive electrode active material and a negative electrode active material, are arranged with a separator interposed therebetween, and a pouch, which is an exterior material that seals and houses the electrode assembly together with an electrolytic solution.

[0004] Among them, all-solid-state secondary batteries are secondary batteries in which all main materials are solid. By using a solid electrolyte, the risk of fire and explosion is significantly reduced, the scope of utilization is widened, and although the performance is extremely excellent, lithium metal, which could not be used due to the risk of fire and explosion, can be used as a negative electrode material, so that the energy density can be dramatically increased. Due to these advantages, development of all-solid-state secondary batteries is currently actively underway.

[0005] In such a secondary battery for all-solid state, since ions move between the solid lattices, it is necessary to minimize the interfacial resistance while maximizing the contact interface between the active material and the electrolyte. For this purpose, after laminating the solid electrolyte layer, a high-temperature pressurization process under isotropic pressure conditions must be performed through a fluid that is a pressure transmission medium. At this time, when pressurizing the all-solid-state secondary battery under isotropic pressure conditions, a device configuration such as a jig for ensuring airtightness is required to protect the all-solid-state secondary battery from the fluid that is the pressure transmission medium.

[0006] For this reason, the inventor of the present invention presents the configuration of a novel pressurization and airtight device for an all-solid-state secondary battery, the details of which will be described later.

Prior Art Documents

Patent Documents

[0007]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0008] The present invention was devised to solve the problems of the aforementioned prior art. The purpose is to provide a pressurization and airtight device for an all-solid-state secondary battery that forms an internal space for transmitting a pressure to the secondary battery while vacuum-adsorbing one side to seal the all-solid-state secondary battery, so that the secondary battery is pressurized under isotropic pressure conditions during the high-temperature pressurization process.

[0009] Also, an object of the present invention is to provide a pressurization and airtight device for an all-solid-state secondary battery that prevents the inflow of fluid into the internal space by forming an adsorption part on one side of the upper cover and the lower cover.

[0010] Further, an object of the present invention is to provide a pressurization airtight device for all-solid-state secondary batteries in which an internal space is evacuated by, for example, vacuum-sucking an upper cover and a lower cover with silicone.

[0011] Further, an object of the present invention is to provide a pressurization airtight device for all-solid-state secondary batteries that prevents overall shape deformation to the maximum extent when a pressing force by a heat transfer medium oil is applied by forming a shape fixing portion on one side of the upper cover and the lower cover.

[0012] Further, an object of the present invention is to provide a pressurization airtight device for all-solid-state secondary batteries that enables both the upper surface and the bottom surface of a secondary battery located therebetween to be contacted and pressurized by forming a pressurization surface on one side of the upper cover and the lower cover so as to face each other.

[0013] Further, an object of the present invention is to provide a pressurization airtight device for all-solid-state secondary batteries that has excellent heat resistance and elongation rate characteristics by forming a pressurization surface made of a silicone material.

Means for Solving the Problems

[0014] In order to achieve the above object, the present invention can be realized by an embodiment having the following configuration.

[0015] According to an embodiment of the present invention, the all-solid-state secondary battery pressurization and airtight device according to the present invention includes an airtight part including a lower cover and an upper cover that is vacuum-adsorbed to one side of the lower cover and forms an internal space in which the all-solid-state secondary battery is disposed; the upper cover includes a first pressurizing part for pressurizing the upper side of the secondary battery in the internal space of the airtight part; the first pressurizing part includes a first pressurizing surface that is pressurized by a fluid during the pressurization process so that the upper surface of the secondary battery in the internal space of the airtight part is pressurized; the lower cover includes a second pressurizing part for pressurizing the lower side of the secondary battery in the internal space of the airtight part; and the second pressurizing part includes a second pressurizing surface that is pressurized by a fluid during the pressurization process so that the bottom surface of the secondary battery in the internal space of the airtight part is pressurized.

[0016] According to another embodiment of the present invention, the upper cover in the all-solid-state secondary battery pressurization and airtight device according to the present invention further includes a first adsorption part that is formed at an end or an edge side of the upper cover and is adsorbed to one side of the lower cover.

[0017] According to another embodiment of the present invention, the upper cover in the all-solid-state secondary battery pressurization and airtight device according to the present invention further includes a first shape fixing part for maintaining the shape of the upper cover during the pressurization process.

[0018] According to another embodiment of the present invention, the first shape fixing part in the all-solid-state secondary battery pressurization and airtight device according to the present invention has an upper and lower thickness that is thicker than the first pressurizing surface.

[0019] According to another embodiment of the present invention, the all-solid-state secondary battery pressurization and airtight device according to the present invention is characterized in that the internal space of the airtight part is evacuated by the adsorption of the first adsorption part.

[0020] According to another embodiment of the present invention, the upper cover in the all-solid-state secondary battery pressurization and airtight device according to the present invention further includes a first detachment part that is formed on one side of the upper cover and allows the upper cover to be detached from the lower cover at the end of pressurization.

[0021] According to another embodiment of the present invention, in the first desorption part of the all-solid-state secondary battery pressurization and airtight device according to the present invention, a first desorption hole extending in one direction is formed.

[0022] According to another embodiment of the present invention, the first pressurization part in the all-solid-state secondary battery pressurization and airtight device according to the present invention is a groove shape formed on the upper surface of the upper cover, and further includes a first pressurization groove for pressing the first pressurization surface and the upper surface of the secondary battery in close contact.

[0023] According to another embodiment of the present invention, the first adsorption part in the all-solid-state secondary battery pressurization and airtight device according to the present invention is formed in a shape with rounded edges on each side.

[0024] According to another embodiment of the present invention, the lower cover in the all-solid-state secondary battery pressurization and airtight device according to the present invention further includes a second shape fixing part for maintaining the shape of the lower cover during the pressurization process, and a second adsorption part formed at an end or an edge side of the lower cover and adsorbed to the first adsorption part.

[0025] According to another embodiment of the present invention, the lower cover in the all-solid-state secondary battery pressurization and airtight device according to the present invention further includes a second desorption part formed at an end side of the lower cover for allowing the lower cover to be desorbed from the upper cover at the end of pressurization.

[0026] According to another embodiment of the present invention, the second pressurization part in the all-solid-state secondary battery pressurization and airtight device according to the present invention is a groove shape formed on the bottom surface of the lower cover, and further includes a second pressurization groove for pressing one side of the second pressurization part and the bottom surface of the secondary battery in close contact.

[0027] According to another embodiment of the present invention, the first pressurization surface and / or the second pressurization surface in the all-solid-state secondary battery pressurization and airtight device according to the present invention includes a silicone material.

[0028] According to another embodiment of the present invention, the first pressure surface and / or the second pressure surface in the all-solid-state secondary battery pressurization and airtight device according to the present invention are characterized by including a silicone material.

[0029] According to another embodiment of the present invention, the first pressure surface and / or the second pressure surface in the all-solid-state secondary battery pressurization and airtight device according to the present invention are characterized by having a thickness of 0.5T or more and less than 1T, respectively.

Advantages of the Invention

[0030] The present invention has the following effects by the above-described configuration.

[0031] The present invention has the effect of pressurizing the secondary battery under isotropic pressure conditions during the high-temperature pressurization process by forming an internal space in which one side is vacuum-adsorbed and pressure is transmitted to the secondary battery while sealing the all-solid-state secondary battery.

[0032] In addition, the present invention has the effect of preventing the inflow of fluid into the internal space by forming an adsorption portion on one side of the upper cover and the lower cover.

[0033] In addition, the present invention has the effect of forming a vacuum in the internal space by vacuum-adsorbing the upper cover and the lower cover with, for example, silicone.

[0034] In addition, the present invention has the effect of preventing overall shape deformation to the maximum extent when pressure is applied by the heat transfer medium oil by forming a shape fixing portion on one side of the upper cover and the lower cover.

[0035] In addition, the present invention has the effect of making it possible to contact and pressurize both the upper surface and the bottom surface of the secondary battery located therebetween by forming the pressure surfaces on one side of the upper cover and the lower cover so as to face each other.

[0036] In addition, the present invention has the effect of forming a pressure surface made of a silicone material to have excellent heat resistance and elongation characteristics.

[0037] It should be added that even for effects not explicitly mentioned here, the effects described in the following specification expected by the technical features of the present invention and their provisional effects are to be treated as described in the specification of the present invention.

Brief Description of the Drawings

[0038]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Modes for Carrying Out the Invention

[0039] Hereinafter, embodiments of the present invention will be described in more detail with reference to the accompanying drawings. The embodiments of the present invention can be modified into various forms, and the scope of the present invention should not be construed as being limited to these embodiments, but should be construed based on the matters described in the claims. Also, the present embodiment is merely provided for reference to more fully explain the present invention to those having ordinary knowledge in the art.

[0040] As used herein, the singular form can include the plural form unless the context clearly indicates otherwise. Also, when used in this specification, "comprise" and / or "comprising" identify the presence of the recited shape, number, step, operation, member, element, and / or group thereof, and do not preclude the presence or addition of one or more other shapes, numbers, operations, members, elements, and / or groups.

[0041] Hereinafter, when it is described that a certain component (or layer) is disposed on another component (or layer), it should be noted that a certain component may be directly disposed on another component, or another component or layer may be interposed between the components. Also, when a certain component is expressed as being directly disposed on another component, no other component is located between the components. Also, a certain component being "on", "above", "below", "upper side", "lower side", "one side", or "side surface" means a relative positional relationship.

[0042] Hereinafter, with reference to the accompanying drawings, the all-solid-state secondary battery pressurization airtight device 1 according to an embodiment of the present invention will be described in detail.

[0043] FIG. 1 is a perspective view showing a pressure-tight device for a solid-state secondary battery, FIG. 2 is an exploded perspective view showing the pressure-tight device for a solid-state secondary battery according to FIG. 1, FIG. 3 is a plan view showing the pressure-tight device for a solid-state secondary battery according to FIG. 1, FIG. 4 is a cross-sectional view showing the pressure-tight device for a solid-state secondary battery according to FIG. 1, and FIG. 5 is a bottom view showing the upper cover of the pressure-tight device for a solid-state secondary battery according to FIG. 1.

[0044] Referring to FIGS. 1 to 5, the present invention relates to a pressure-tight device 1 for a solid-state secondary battery, and an internal space is formed such that one side is vacuum-adsorbed to seal the solid-state secondary battery 9 while transmitting a pressing force to the secondary battery 9, so that the secondary battery 9 is pressed under isotropic pressure conditions during the high-temperature pressing process. The present invention relates to a pressure-tight device 1 for a secondary battery. Such a pressure-tight device 1 is preferably formed of, for example, a silicone material, and detailed content thereof will be described later.

[0045] For this purpose, the pressure-tight device 1 may include an airtight portion 10.

[0046] Referring to FIGS. 1 to 5, the airtight portion 10 is configured to form the outer surface of the pressure-tight device 1. Such an airtight portion 10 can make, for example, a unit cell or a bi-cell airtight in its internal space, but there is no separate limitation thereto. Also, there is no limitation to the shape of the airtight portion 10, but as an example, it may have a polygonal planar shape with rounded edges on each side. Further, the airtight portion 10 can be formed of a material having a high elongation rate characteristic on at least one side so that the internal secondary battery 9 can be pressed. As an example, the airtight portion 10 can be formed of a silicone material.

[0047] With such a configuration of the airtight portion 10, when performing the pressurization process, it is possible to prevent a fluid such as heat transfer medium oil from penetrating into the internal space of the airtight portion 10 and coming into contact with the secondary battery 9. Specifically, when a fluid such as heat transfer medium oil flows into the vessel and a pressure above a predetermined level is transmitted to the airtight portion 10, at least one side of the airtight portion 10 can pressurize the secondary battery 9 disposed in the internal space. Therefore, the airtight portion 10 can be configured to perform the high-temperature pressurization process while protecting the secondary battery 9 so that the secondary battery 9 disposed in the internal space does not come into direct contact with the fluid.

[0048] For this purpose, the airtight portion 10 can include an upper cover 110 and a lower cover 130. For example, the upper cover 110 and the lower cover 130 are preferably formed in corresponding shapes to protect the secondary battery 9 from the fluid. The term "internal space" can create a vacuum environment in the sealed space where the secondary battery 9 is disposed by the upper cover 110 and the lower cover 130. That is, the upper cover 110 and the lower cover 130 can be configured to be vacuum-adsorbed to each other.

[0049] The upper cover 110 is configured to be coupled to the lower cover 130 such that a all-solid-state secondary battery 9 is disposed therebetween. For example, the upper cover 110 can be coupled to or vacuum-adsorbed to one side of the lower cover 130 to cover the secondary battery 9. For this purpose, the upper cover 110 can include a first pressurizing portion 111, a first shape fixing portion 113, a first adsorbing portion 115, and a first desorbing portion 117.

[0050] The first pressing part 111 is configured to press the upper surface of the all-solid-state secondary battery 9 in the internal space of the airtight part 10. Such a first pressing part 111 is formed on one side of the upper cover 110 so that the upper surface of the secondary battery 9 can be pressed. For example, the first pressing part 111 may be formed in a predetermined shape on the substantially central side of the upper cover 110. As an example, the first pressing part 111 may be formed in a square planar shape on the substantially central side of the upper cover 110, but the scope of the present invention is not limited thereto. For this purpose, the first pressing part 111 can include a first pressing groove 1111 and a first pressing surface 1113.

[0051] The first pressing groove 1111 is a groove-shaped configuration formed on the upper surface of the upper cover 110, and the upper surface of the secondary battery 9 and the first pressing surface 1113 can be brought into close contact and pressed. For example, the first pressing groove 1111 may be a groove-shaped configuration formed to have a step downward on one side of the upper cover 110, and the scope of the present invention is not limited by specific examples. Also, when a pressure equal to or higher than a predetermined level is applied to the upper cover 110, the first pressing groove 1111 is formed, for example, to have a step downward so as to easily transmit the pressure to the upper surface side of the secondary battery 9, and the first pressing surface 1113 can be formed to be relatively thinner than the surrounding configurations such as the first shape fixing part 113. Therefore, the first pressing surface 1113 can be in close contact with the secondary battery 9 disposed in the internal space of the airtight part 10 and easily transmit the pressing force.

[0052] The first pressing surface 1113 is configured to be pressed by a fluid such as heat medium oil during the process so that the upper surface of the secondary battery 9 in the internal space of the airtight portion 10 is pressed. For example, the first pressing surface 1113 is formed to face the second pressing surface 1313 of the lower cover 130 described later, and the upper and lower surfaces of the secondary battery 9 located therebetween can be configured to be pressable respectively. Also, it is preferable that the pair of pressing surfaces 1113, 1313 are formed such that their opposing surfaces are substantially flat so as to press the secondary battery 9 with the upper and lower surfaces in close contact under isotropic pressure conditions. As described above, the first pressing surface 1113 preferably has a thinner upper and lower thickness than the first shape fixing portion 113. A specific description of the upper and lower thickness of the first pressing surface 113 will be described later.

[0053] The first shape fixing portion 113 is configured to be formed between the first pressing portion 111 and the first adsorption portion 115, and can maintain the shape of the upper cover 110 during the pressing process. Although there is no limitation on the shape of such a first shape fixing portion 113, as an example, it may have a rectangular frame shape with rounded edges on its edge side. For example, the first shape fixing portion 113 is formed to face the second shape fixing portion 133 of the lower cover 130, and can maintain the shape of the airtight portion 10 during the pressing process. More specifically, the pair of shape fixing portions 113, 133 are formed in a frame shape along the outside of the pressing portions 111, 131 in order to maintain the shape of the airtight portion 10, and even if the pressing portions 111, 131 are deformed in shape during the vacuum adsorption of the upper cover 110 and the lower cover 130 or during the high-temperature pressing process, it is possible to prevent the outer configuration of the pressing portions 111, 131 from being deformed as much as possible. Therefore, the first shape fixing portion 113 preferably has a larger upper and lower thickness than the first pressing portion 111 and / or the first adsorption portion 115 described later.

[0054] The first suction part 115 is formed on one side of the upper cover 110, for example, at the end or the edge side, and is configured to form a vacuum in the internal space of the airtight part 10 or, conversely, to release the vacuum by vacuum suction with the second suction part 135. Such a first suction part 115 is formed in a polygonal planar shape with rounded edges along the outside of the first shape fixing part 113, and can be vacuum-sucked with the second suction part 135 so that a vacuum environment is formed in the internal space of the airtight part 10 during the pressurization process for the secondary battery 9. At this time, the first suction part 115 is preferably formed in a shape with rounded edges on each side in order to ensure the maximum airtightness of the internal space of the airtight part 10 under the isotropic pressure condition by the heat medium oil.

[0055] For example, when the first suction part 115 and the second suction part 135 are formed in a polygonal frame shape such as a square frame shape, even if the suction parts 115 and 135 are vacuum-sucked with each other, the airtightness will only be lower compared to an embodiment of the present invention. The first suction part 115 is preferably formed of a silicone material and vacuum-sucked with the first suction part 135. The above-mentioned "vacuum environment" can mean an environment having a pressure value lower than the atmospheric pressure.

[0056] Also, the first suction part 115 is preferably formed so as to incline toward the end side of the adjacent upper cover 110, and more preferably formed so as to incline downward toward the end side of the upper cover 110. For example, the first suction part 115 can be formed in a cross-sectional shape that inclines from the end side of the adjacent first shape fixing part 113 toward the end side of the adjacent upper cover 110. More specifically, the pair of suction parts 115 and 135 can be inclined so as to converge with each other toward the end side of the adjacent airtight part 10 for ensuring the airtightness of the internal space of the airtight part 10 and for easy vacuum suction between them. Such a first suction part 115 is vacuum-sucked with the second suction part 135. At this time, the upper and lower surfaces of the secondary battery 9 disposed in the internal space of the airtight part 10 can be in contact with or at least partially in close contact with the respective pressurizing surfaces 1113 and 1313, but there is no separate limitation thereto.

[0057] The first detaching part 117 is formed on one side of the upper cover 110 and is configured such that the upper cover 110 is detached from the lower cover 130 at the end of the pressing process. For example, the first detaching part 117 can be formed on both end sides of the upper cover 110, and at the end of the pressing process, the second detaching part 137 can be utilized together so that the two covers 110 and 130 are separated. Specifically described, the first detaching part 117 can be formed on the side that overlaps vertically with the second detaching part 137 of the lower cover 130.

[0058] Also, a first detaching hole 1171 is formed on one side of the first detaching part 117, and at the end of the pressing, the first detaching hole 1171 can be utilized to separate the upper cover 110 and the lower cover 130 from each other. For example, by utilizing the first detaching hole 1171 of the first detaching part 117 and the second detaching hole 1371 of the second detaching part 137, the upper cover 110 and the lower cover 130 can be separated at the end of the pressing. As an example, by inserting a detaching means into the first detaching hole 1171 and the second detaching hole 1371, the upper cover 110 and the lower cover 130 can be made to end the vacuum adsorption. Here, the "detaching means" refers to a pin or bolt configuration, etc., and means for releasing the vacuum of a device with airtightness ensured by inserting it into the detaching hole. Alternatively, an operator can also manually separate the two covers 110 and 130 using the first detaching hole 1171 and the second detaching hole 1371, and the present invention is not limited by specific exemplifications. The aforementioned first detaching hole 1171 and second detaching hole 1371 may both extend in the horizontal direction or in the vertical direction, but the scope of the present invention is not limited thereto and may be a configuration of a through hole having any shape, and in some cases, may be formed in a groove shape.

[0059] Referring to FIGS. 1 to 5, the lower cover 130 is configured to be coupled to the upper cover 110 so that the all-solid-state secondary battery 9 is disposed therebetween. For example, the lower cover 130 can be coupled to one side of the upper cover 110 to cover the secondary battery 9. The lower cover 130 is symmetric with the upper cover 110 along the x-axis (or horizontal plane) direction and includes substantially the same configuration. However, it should be noted that the configuration corresponding to at least one of the second pressing portion 131, the second shape fixing portion 133, the second adsorption portion 135, and the second desorption portion 137 may be omitted in some cases.

[0060] For this purpose, the lower cover 130 can include a second pressing portion 131, a second shape fixing portion 133, a second adsorption portion 135, and a second desorption portion 137.

[0061] The second pressing portion 131 is configured to press the bottom surface of the all-solid-state secondary battery 9 in the internal space of the airtight portion 10. Such a second pressing portion 131 is formed on one side of the lower cover 130 so that the bottom surface of the secondary battery 9 can be pressed. For example, the second pressing portion 131 is preferably formed in a predetermined shape on the substantially central side of the lower cover 130 and in a shape corresponding to the first pressing portion 111. Such a second pressing portion 131 can include a second pressing groove 1311 and a second pressing surface 1313.

[0062] The second pressure groove 1311 is a groove-shaped structure formed on the bottom surface of the lower cover 110, and the bottom surface of the secondary battery 9 and the second pressure surface 1113 can be brought into close contact and pressurized. For example, the second pressure groove 1311 may be a groove-shaped structure formed to have a step on one side of the lower cover 130, and the scope of the present invention is not limited by specific examples. Further, when a pressure equal to or higher than a predetermined level is applied to the lower cover 130, the second pressure groove 1311 is formed, for example, to have a step upward so as to easily transmit the pressure to the bottom surface side of the secondary battery 9, whereby the second pressure surface 1313 can be formed relatively thinner than the surrounding structures such as the second shape fixing portion 133. Therefore, the second pressure surface 1313 can be in close contact with the secondary battery 9 disposed in the internal space of the airtight portion 10 and easily transmit the pressing force.

[0063] The second pressure surface 1313 is a planar configuration that is pressurized by a fluid such as heat transfer medium oil during the process so that the bottom surface of the secondary battery 9 in the internal space of the airtight portion 10 is pressurized. For example, the second pressure portion 1313 can be formed to face the first pressure surface 1113 of the upper cover 110 described above and configured to contact and pressurize both the upper and lower surfaces of the secondary battery 9. Such a second pressure surface 1313 preferably has a smaller thickness in the vertical direction than the second shape fixing portion 133.

[0064] The second shape fixing portion 133 is configured to be formed between the second pressing portion 131 and the second suction portion 135, and can maintain the shape of the lower cover 130 during the pressing process. Although there is no limitation on the shape of such a second shape fixing portion 133, for example, it may have a rectangular frame-shaped planar shape. The second shape fixing portion 133 is formed so as to face the first shape fixing portion 113 of the upper cover 110, and can maintain the shape of the lower cover 130 during the pressing process. With such a second shape fixing portion 133, even if the shape of the second pressing portion 131 is somewhat deformed by the pressing force of a fluid such as heat medium oil, the shape deformation of the outer configuration can be prevented. Therefore, it is preferable that the second shape fixing portion 133 has a greater vertical thickness than the second pressing portion 131 and / or the second suction portion 135 described later. The second shape fixing portion 133 is preferably formed in substantially the same shape as the first shape fixing portion 113, but the scope of the present invention is not limited thereto.

[0065] The second suction portion 135 is formed on one side of the lower cover 130, for example, at an end or an edge side, and together with the first suction portion 115, is vacuum-sucked to form a vacuum in the internal space of the airtight portion 10 or, conversely, to release the vacuum. Such a second suction portion 135 can be formed in a polygonal planar shape with rounded edges along the outside of the second shape fixing portion 133. At this time, the second suction portion 135 is preferably formed in a shape with rounded edges on each edge side in order to ensure the maximum airtightness with respect to the internal space of the airtight portion 10 under the isotropic pressure pressing conditions by the heat medium oil.

[0066] Further, the second adsorption portion 135 is preferably formed to incline toward the end side of the lower cover 130, and more preferably formed to incline upward toward the end side of the lower cover 130. For example, the second adsorption portion 135 can be formed in a cross-sectional shape that inclines from the outside of the second shape fixing portion 133 toward the end side of the lower cover 130. Such a second adsorption portion 135 is vacuum-adsorbed to the first adsorption portion 115. At this time, the upper surface and the bottom surface of the secondary battery 9 disposed in the internal space of the airtight portion 10 can contact the respective pressing surfaces 1113 and 1313 or at least maintain a partially adhered state. Also, the second adsorption portion 135 is preferably formed of a silicone material.

[0067] Generally, during the high-temperature pressing process for the all-solid-state secondary battery 9, if the process is performed with air remaining inside the airtight portion 10, there will inevitably be defects in the resulting product. That is, the isotropic pressure conditions for the internal secondary battery 9 cannot be satisfied due to the remaining air. For this reason, the pressure-tightening device 1 according to an embodiment of the present invention can form a vacuum in the internal space through the vertical vacuum adsorption between the upper cover 110 and the lower cover 130.

[0068] FIG. 6 is a reference diagram showing the pressure application result of the pressure-reducing paper for the secondary battery pressure-tightening device in a state where the internal space is not evacuated.

[0069] Vacuum suction Referring to FIGS. 1 to 5, the first suction part 115 and the second suction part 135 have corresponding shapes for vertical suction, and vacuum-suck the end side and / or the internal space of the airtight part 10 so that the secondary battery 9 is pressurized. To explain in detail, the pair of suction parts 115 and 135 can be formed to converge from the outside of the second shape fixing part 133 toward the end side of the lower cover 130 or the end side of the upper cover 110 in order to ensure the airtightness of the internal space of the airtight part 10. Such a pair of suction parts 115 and 135 are formed in a polygonal planar shape with rounded edges along the outside of the shape fixing parts 113 and 135, and a vacuum environment can be formed in the internal space of the airtight part 10 during the pressurization process for the secondary battery 9. At this time, the upper and lower surfaces of the secondary battery 9 disposed in the internal space of the airtight part 10 can contact the respective pressurization surfaces 1113 and 1313 or at least maintain a state of being in partial contact.

[0070] Referring to FIG. 6, after the secondary battery 9 is disposed in the internal space of the airtight part 10, a pressurization process is performed using thermal medium oil or water under normal temperature environment at a pressure of 2000 bar for 1 minute. As described above, FIG. 6 shows the pressure reduction paper pressurization result in a state where the internal space is not evacuated.

[0071] At this time, the pressurization of the secondary battery 9 can be confirmed, but air bubbles are generated due to the inflow of air into the internal space, and thus deformation occurs on the pressurization surfaces 1113 and 1313. Also, it can be seen that the uniformity of the pressurization result is low. Therefore, in order to prevent such problems, separate vacuum means communicating with the outside can be provided, but the pressurization airtight device 1 according to an embodiment of the present invention performs the pressurization process through the vertical vacuum suction between the upper cover 110 and the lower cover 130.

[0072] FIG. 7 is a table showing the physical properties of the pressurization surface made of silicone material.

[0073] Materials of the pressing surfaces 1113 and 1313 Generally, when subjecting the all-solid-state secondary battery 9 to high-temperature pressurization, the process is preferably carried out in a pressure environment of about 100° or higher, more preferably about 200° or higher at maximum, and 7000 bar. Also, since the pressurization process according to an embodiment of the present invention is carried out in an environment of about 200°, it is preferable to utilize heat transfer oil rather than using water, but it is not limited thereto.

[0074] Therefore, the pressurizing surfaces 1113 and 1313 that come into contact with and are pressurized against the upper and lower surfaces of the secondary battery 9 need to be made of a material with high elongation rate characteristics so that pressure is applied to all surfaces of the secondary battery 9 due to the isotropic pressure characteristics where pressurization is performed in all directions with respect to the secondary battery 9. Generally, film materials such as PTFE (Polytetrafuoroethylene), PEEK (Polyether ether ketone), and PI (Polyimides), which are materials utilized in the pressurization process, have high performance in heat resistance and oil resistance, but have relatively low elongation rate characteristics, and since there is no way to complement this part, it is difficult to use them as pressurizing materials. At this time, the elongation rate characteristic means the state of being stretched. In one embodiment of the present invention, it means the property for the pressurizing material to adhere along the outer shape of the pressurization target, and also means the property of having a restoring force for repeated use.

[0075] The pressurizing surfaces 1113 and 1313 according to an embodiment of the present invention are preferably made of a silicone material having high elongation rate characteristics. Here, the "silicone" material refers to a pressurizing material selected by complementing the oil resistance, which is a weak point, while satisfying the elongation rate characteristics and heat resistance that a rubber material has.

[0076] For this purpose, referring to FIG. 7, the comparison table is a reference diagram showing the physical properties of steam-resistant silicone (KCC SILICONE; SH6070U), heat-resistant silicone (KCC SILICONE; SH9161U), and fluorosilicone (KCC SILICONE; FQE205) along the left-to-right direction. The pressure surfaces 1113 and 1313 according to an embodiment of the present invention can be made of steam-resistant silicone, heat-resistant silicone, or fluorosilicone, and preferably made of fluorosilicone among them. However, the scope of the present invention is not limited thereto. Details regarding the selection of the pressurizing material of fluorosilicone will be described below.

[0077] The test is conducted under the conditions of 150 °C, a holding time of 70 hours, and IRM 903 oil (ASTM Oil TEST Reference Oil). As a result of the test, considering characteristics such as change of volume, change of hardness, change of tensile strength, and change of elongation, a fluorosilicone showing the best performance in terms of oil resistance, which is a weakness of silicone materials, is selected. However, when using water or the like, which is not a heat transfer medium oil, as the pressure transmission medium during the pressurizing process, it is not necessary to limit the pressure surfaces 1113 and 1313 according to an embodiment of the present invention to fluorosilicone.

[0078] FIG. 8 is a cross-sectional view showing a secondary battery pressurizing and airtight device for all-solid-state batteries according to a second embodiment of the present invention.

[0079] As a second embodiment, referring to FIG. 8, the shape fixing portions 213 and 233 are configured to be formed between the pressing portions 211 and 231 and the suction portions 215 and 235 (to be described later), and can maintain the shape of the airtight portion 20 during the pressing process. Although there is no limitation on the shape of such shape fixing portions 213 and 233, as an example, they can have a rectangular frame-shaped planar shape. For example, the first shape fixing portion 213 is formed to face the second shape fixing portion 233 of the lower cover 230, and can maintain the shape of the upper cover 210 during the pressing process. Specifically described, the pair of shape fixing portions 213 and 233 are formed in a frame shape along the outside of the pressing portions 211 and 231 in order to maintain the shapes of the upper cover 210 and the lower cover 230, and can prevent the outer configuration of the pressing portions 211 and 231 from deforming in shape during the high-temperature pressing process.

[0080] Also, the shape fixing portions 213 and 233 can be formed to overlap vertically with the suction portions 215 and 235 in order to strengthen the shape maintenance of the airtight portion 20. For example, the shape fixing portions 213 and 233 extend with substantially the same vertical thickness on the end side of the suction portions 215 and 235, and can strengthen the prevention of shape deformation of the airtight portion 20 due to surface pressing during the pressing process. With such shape fixing portions 213 and 233, although the shapes of the pressing portions 211 and 231 are deformed by the pressing force of the heat medium oil, the shape deformation of the outer configuration thereof can be prevented. Therefore, it is preferable that the shape fixing portions 213 and 233 and the suction portions 215 and 235 have a larger vertical thickness than the pressing portions 211 and 231.

[0081] The suction portions 215 and 235 are configured as suction pads formed on one side of the airtight portion 20 in a state where the upper cover 210 and the lower cover 230 are coupled, and can block not only the end side of the airtight portion 20 but also the internal space communicating with the shape fixing portions 213 and 233 so that the internal space of the airtight portion 20 can be evacuated or the vacuum can be released.

[0082] Specifically, the pair of suction portions 215 and 235 can be formed to converge with each other from the outside of the shape fixing portions 213 and 233 toward the end side of the upper cover 210 for forming a vacuum in the internal space of the airtight portion 20. At this time, the opposing surfaces of the suction portions 215 and 235 can be pressed against each other so that the end sides of the upper cover 210 and the lower cover 230 are vacuum-sucked.

[0083] Further, the suction portions 215 and 235 are formed with a flat central side of the internal space, and one side of the suction portions 215 and 235 is formed in a cross-sectional shape that is inclined from the central side toward the end side of the airtight portion 10, so that the inflow of a fluid (for example, water) during the pressing process can be blocked to ensure the airtightness of the airtight portion 20. Further, the other side of the suction portions 215 and 235 is formed in a cross-sectional shape that is inclined from the central side toward the shape fixing portions 213 and 233, so that the airtightness of the airtight portion 20 when the upper cover 210 and the lower cover 230 are vertically suctioned can be enhanced.

[0084] Therefore, when performing the pressing process, it is possible to prevent a fluid such as heat medium oil from penetrating into the internal space of the airtight portion 20 and contacting the secondary battery 9. For example, by vacuum-sucking the upper cover 210 and the lower cover 230 made of a silicone material, it is possible to prevent a heat medium oil or the like from flowing into the internal spaces of the suction portions 215 and 235, the shape fixing portions 213 and 233, and the pressing portions 211 and 231 and contacting the secondary battery 9.

[0085] Specifically, when a fluid such as heat medium oil flows into the vessel and a pressure equal to or higher than a predetermined level is transmitted to the airtight portion 20, the pressing portions 211 and 231 of the airtight portion 20 can press the secondary battery 9 disposed in the internal space. At this time, the airtight portion 20 can be configured to perform a high-temperature pressing process while protecting the secondary battery 9 so that the secondary battery 9 in the internal space does not directly contact the heat medium oil.

[0086] FIG. 9 is a reference diagram showing the pressing result according to the hardness of the pressing surface according to an embodiment of the present invention.

[0087] Hardness of the pressing surfaces 1113 and 1313 Referring to FIG. 9, in a pressing device having pressing surfaces with different hardnesses, a pressure-reducing paper 3EA is disposed in the internal space of the airtight portion 10, and copper foils treated with graphite are disposed on the uppermost and lowermost sides of the pressure-reducing paper. The mold silicone constituting the pressing surfaces 1113 and 1313 is formed in two types with a hardness of 5 (Comparative Example 1, FIG. 9(a)) and a hardness of 20 (Comparative Example 2, FIG. 9(b)).

[0088] Thereafter, a pressing process is performed using water under normal temperature conditions at a pressure of 2000 bar for 1 minute. When the results thereof are confirmed, a significantly increased pressing rate can be confirmed as compared with Comparative Examples 1 to 2. Therefore, it can be seen that the lower the silicone hardness of the pressing surface, the more advantageous it is for the pressing process.

[0089] FIG. 10 is a reference diagram showing the pressing results according to the thickness of the pressing surface according to an embodiment of the present invention.

[0090] Thickness of the pressing surfaces 1113 and 1313 Referring to FIG. 10, the thicknesses of the pressing surfaces made of silicone are set to 0.5T, 1T, and 2T, and a pressing process is performed using water under normal temperature conditions at a pressure of 2000 bar for 1 minute. At this time, the configurations of the pressing surfaces 1113 and 1313 are substantially the same as those described above, and a pressure-reducing paper 5EA is disposed in the internal space of the airtight portion 10.

[0091] As a result of the pressing process, it can be seen that the pressing surfaces 1113 and 1313 with a thickness of 0.5T have significantly increased pressing results and pressing uniformity. Also, the pressing results of the pressing surfaces 1113 and 1313 with a thickness of 1T and the pressing surfaces 1113 and 1313 with a thickness of 2T are similar, but it can be seen that the pressing surfaces 1113 and 1313 with a thickness of 1T have higher pressing uniformity.

[0092] Thereby, it can be seen that the thinner the thickness of the pressing surfaces 1113 and 1313, the more uniform the higher pressing results are. Therefore, the pressing surfaces 1113 and 1313 according to an embodiment of the present invention preferably have a thickness of about 1T or less, and more preferably 0.5T or more and less than 1T.

[0093] The above detailed description is illustrative of the present invention. Also, the foregoing content shows and describes preferred embodiments of the present invention, and the present invention can be used in various different combinations, modifications, and environments. That is, changes and modifications are possible within the scope of the concept of the invention disclosed in this specification, the scope equivalent to the described disclosure, and / or the scope of technology or knowledge in the art. The foregoing embodiments illustrate the best state for realizing the technical idea of the present invention, and various changes required in the specific application fields and uses of the present invention are also possible. Therefore, the above detailed description of the invention is not intended to limit the present invention to the disclosed embodiments.

Explanation of Reference Numerals

[0094] 1 Secondary battery pressurized airtight device for all-solid-state batteries 10 Airtight part 110 Upper cover 111 First pressurizing part 1111 First pressurizing groove 1113 First pressurizing surface 113 First shape fixing part 115 First adsorbing part 117 First desorbing part 1171 First desorbing hole 130 Lower cover 131 Second pressurizing part 1311 Second pressurizing groove 1313 Second pressurizing surface 133 Second shape fixing part 135 Second adsorbing part 137 Second desorbing part 1371 Second desorbing hole 9 Secondary battery for all-solid-state batteries

Claims

1. An airtight portion including a lower cover and an upper cover that is vacuum-adsorbed to one side of the lower cover and forms an internal space in which a all-solid-state secondary battery is disposed; The upper cover, includes a first pressurizing portion that pressurizes the upper side of the secondary battery in the internal space of the airtight portion, The first pressurizing portion, includes a first pressurizing surface that is pressurized by a fluid during a pressurizing process so that the upper surface of the secondary battery in the internal space of the airtight portion is pressurized; The lower cover, includes a second pressurizing portion that pressurizes the lower side of the secondary battery in the internal space of the airtight portion; The second pressurizing portion, includes a second pressurizing surface that is pressurized by a fluid during a pressurizing process so that the bottom surface of the secondary battery in the internal space of the airtight portion is pressurized, characterized by a all-solid-state secondary battery pressurizing and airtightening device.

2. The upper cover, further includes a first adsorption portion formed at an end or an edge side of the upper cover and adsorbed to one side of the lower cover, characterized by the all-solid-state secondary battery pressurizing and airtightening device according to Claim 1.

3. The upper cover, further includes a first shape fixing portion that maintains the shape of the upper cover during a pressurizing process, characterized by the all-solid-state secondary battery pressurizing and airtightening device according to Claim 2.

4. The first shape fixing portion has an upper and lower thickness that is thicker than the first pressurizing surface, characterized by the all-solid-state secondary battery pressurizing and airtightening device according to Claim 3.

5. The internal space of the airtight portion is evacuated by the adsorption of the first adsorption portion, characterized by the all-solid-state secondary battery pressurizing and airtightening device according to Claim 2.

6. The upper cover, further includes a first detachment portion formed on one side of the upper cover so that the upper cover is detached from the lower cover at the end of pressurization, characterized by the all-solid-state secondary battery pressurizing and airtightening device according to Claim 2.

7. A first detachment hole extending in one direction is formed in the first detachment portion, characterized by the all-solid-state secondary battery pressurizing and airtightening device according to Claim 6.

8. The first pressurizing portion, is a groove shape formed on the upper surface of the upper cover, and further includes a first pressurizing groove that allows the first pressurizing surface and the upper surface of the secondary battery to be in close contact and pressurized, characterized by the all-solid-state secondary battery pressurizing and airtightening device according to Claim 1.

9. The first adsorption portion is formed in a shape with rounded edges on each side, characterized by the all-solid-state secondary battery pressurizing and airtightening device according to Claim 2.

10. The lower cover, a second shape fixing part for maintaining the shape of the lower cover during the pressing process; a second suction part formed at an end or an edge side of the lower cover and suctioned to the first suction part; The secondary battery pressurization airtight device for all solid bodies according to claim 2, further comprising the same.

11. The lower cover A second detachment part formed at an end side of the lower cover and configured to detach the lower cover from the upper cover at the end of pressurization; The secondary battery pressurization airtight device for all solid bodies according to claim 6, further comprising the same.

12. The second pressurizing part A groove shape formed on the bottom surface of the lower cover, and a second pressurizing groove configured to pressurize by closely contacting one side of the second pressurizing part and the bottom surface of the secondary battery; The secondary battery pressurization airtight device for all solid bodies according to claim 1, further comprising the same.

13. The first pressurizing surface and / or the second pressurizing surface includes a silicone material. The secondary battery pressurization airtight device for all solid bodies according to claim 1.

14. The first pressurizing surface and / or the second pressurizing surface each have a thickness of 0.5T or more and less than 1T. The secondary battery pressurization airtight device for all solid bodies according to claim 1.

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