Pouch sealing device that can target heating areas

Abstract

The present invention provides a sealing device structure including a pair of sealing tool assemblies including a heat-radiating sealing tool, a heat-absorbing sealing tool, and a heat-absorbing / dissipating device, wherein the heat-radiating sealing tool and the heat-absorbing sealing tool extend along the width direction and are arranged side by side along the length direction, and the heat-absorbing / dissipating device is interposed between the heat-radiating sealing tool and the heat-absorbing sealing tool to radiate heat to the heat-radiating sealing tool and absorb heat from the heat-absorbing sealing tool.

Description

[Technical Field]

[0001] This application claims the benefit of priority based on Korean Patent Application No. 10-2022-0173079 filed December 12, 2022 and Korean Patent Application No. 10-2023-0066867 filed May 24, 2023, and all contents disclosed in the documents of said Korean patent applications are incorporated herein by reference.

[0002] The present invention relates to a sealing device for fusion-sealing a pouch that houses an electrode assembly in a pouch-type battery cell. [Background technology]

[0003] Secondary batteries, which are highly applicable to a wide range of products and have electrical properties such as high energy density, are widely used not only in portable devices but also in electric vehicles (EVs) and hybrid electric vehicles (HEVs) that are powered by electrical sources.

[0004] These secondary batteries have the primary advantage of dramatically reducing the use of fossil fuels, and also have the advantage of not producing any by-products from the use of energy, making them environmentally friendly and improving energy efficiency, and are therefore attracting attention as a new energy source.

[0005] Currently, widely used types of secondary batteries include lithium-ion batteries, lithium polymer batteries, nickel-cadmium batteries, nickel-metal hydride batteries, and nickel-zinc batteries. The operating voltage of these unit secondary battery cells, i.e., unit battery cells, is approximately 2.5V to 4.5V. Therefore, if a higher output voltage is required, a battery pack may be constructed by connecting multiple battery cells in series. Alternatively, a battery pack may be constructed by connecting multiple battery cells in parallel depending on the required charge / discharge capacity of the battery pack. Therefore, the number of battery cells included in the battery pack and the electrical connection configuration can be variously set depending on the required output voltage and / or charge / discharge capacity.

[0006] Meanwhile, secondary batteries are generally classified into cylindrical batteries and prismatic batteries, in which an electrode assembly is housed in a cylindrical or prismatic metal can, and pouch batteries, in which an electrode assembly is housed in a pouch case made of a pouch film made of a metal foil material, depending on the shape of the battery case.

[0007] FIG. 1 is a perspective view showing the structure of a pouch-type battery cell, and FIG. 2 is a cross-sectional view showing the sealing portion of the pouch-type battery cell. Referring to these drawings, the pouch-type battery cell is formed by housing an electrode assembly 11, which is formed by alternately stacking multiple electrodes and separators, in a pouch 14 made of a metal sheet material. The pouch 14 surrounds the electrode assembly 11 and is sealed with a first sealing portion 143a and a second sealing portion 143b. Electrode tabs 12 extend from the multiple electrodes and are welded to electrode leads 13, which protrude outside the pouch 14 through the first sealing portion 143a. A lead film 131 made of a thermoplastic synthetic resin material attached to the electrode lead 13 is interposed between the pouch 14 and the electrode lead 13.

[0008] 3 is an enlarged cross-sectional view showing the structure of the pouch insulating layer. Referring to FIG. 3, the pouch 14 includes a metal layer 141 and an inner insulating layer 142a and an outer insulating layer 142b, which are respectively coated on the inner and outer surfaces of the metal layer 141. Each insulating layer 142 is made of a thermoplastic synthetic resin. The inner insulating layer 142a insulates the electrode assembly 11 and the electrode tab 12 from the metal layer 141, and the outer insulating layer 142b insulates the outside of the pouch 14 from the metal layer 141.

[0009] 4 and 5 show the structure and arrangement of a typical sealing device. Referring to these figures, a sealing device 2 is used to seal the pouch 14. While the following describes an example of a sealing device that seals the first sealed portion 143a, the same applies to the second sealed portion 143b.

[0010] The sealing device 2 includes a sealing tool 21 for applying pressure and heat to the first sealing portion 143a, a sealing block 22 connected to the sealing tool 21, an insulating frame 24 for accommodating the sealing block 22, and a heat rod 23 inserted into the sealing block 22. The sealing device 2 is a pair, with one disposed on each side of the first sealing portion 143a in the height direction. The sealing tool 21 is provided with a groove 211 having a shape corresponding to the electrode lead 13.

[0011] 6 is a cross-sectional view showing how the sealing device of FIG. 4 seals a pouch. When the heat rod 23 heats the seal block 22, the seal tool 21 is heated via the seal block 22. The seal tool 21 pressurizes and heats the first seal portion 143a, thereby fusing the inner insulating layer 142a and the lead film 131, thereby sealing the pouch 14.

[0012] Meanwhile, the melting point of polypropylene resin, which is primarily used to form the inner insulating layer 142a and the lead film 131, is approximately 160°C, so the sealing tool 21 must be heated to a temperature even higher than this. During sealing, the thermal energy of the sealing tool 21 is not only transferred directly to the first seal portion 143a, but also transferred to the remainder of the pouch 14 (excluding the first seal portion 143a) in the form of conductive heat conducted from the first seal portion 143a along the metal layer 141, and radiant and convective heat transferred from the sealing tool 21 to the pouch 14. These conductive, radiant, and convective heat may melt and damage the insulating layer 142, which may result in poor insulation performance of the pouch 14.

[0013] Furthermore, the sealing tool 21 is exposed to the air, and heat energy is lost in the form of radiant heat and convection heat, which causes a problem of reduced energy efficiency. Summary of the Invention [Problem to be solved by the invention]

[0014] The present invention was conceived in light of the background of the prior art described above, and its object is to provide a sealing device structure that can minimize heat transfer to the remaining portion excluding the sealed portion when sealing a pouch.

[0015] Another object of the present invention is to provide a sealing device structure that prevents damage to the inner and outer insulating layers of the pouch, improves the insulating performance of the battery cell, and reduces the defect rate.

[0016] Another object of the present invention is to provide a sealing device structure that can cool the remaining portion excluding the sealing portion to a temperature below room temperature during sealing.

[0017] A further technical object of the present invention is to provide a sealing device structure that allows precise targeting of a heating area during sealing, heating only the desired area, and leaving the remaining area unheated.

[0018] The present invention also seeks to provide a sealing device design that minimizes heat loss and improves energy efficiency.

[0019] Another object of the present invention is to provide a sealing device structure that can be quickly heated to a high temperature and can maintain the heated state at a constant level.

[0020] Another object of the present invention is to provide a seal device that can achieve the above-mentioned objects, and that has a simple structure and can be manufactured using only a small number of parts.

[0021] The technical object of the present invention is not limited to the above-mentioned objects, and other unmentioned objects and advantages of the present invention can be understood from the following description and can be more clearly understood from the examples of the present invention. Furthermore, it can be easily understood that the objects and advantages of the present invention can be achieved by the means and combinations thereof set forth in the claims. [Means for solving the problem]

[0022] In order to solve the above problems, the present invention provides a structure of a sealing device including a pair of sealing tool assemblies including a heat-radiating sealing tool, a heat-absorbing sealing tool, and a heat-absorbing and heat-radiating device.

[0023] [Example 1] The first embodiment of the present invention can be applied to a sealing device that fusion-seals first seal portions that are provided at both longitudinal ends of a pouch included in a pouch-type battery cell and extend along the width direction. The battery cell may include electrode leads that extend from inside the pouch and protrude through the first seal portions.

[0024] The heat-dissipating seal tool may be formed to extend in the width direction. The heat-dissipating seal tool may be provided with a first groove portion corresponding to the shape of the electrode lead.

[0025] According to the first embodiment of the present invention, the first groove may be recessed from one end of the heat-dissipating seal tool in a widthwise center section toward the other end in the height direction. The widthwise length of the first groove may correspond to the width of the electrode lead, and the depth may correspond to the thickness of the electrode lead or half thereof.

[0026] The heat-absorbing sealing tool may be formed to extend in the width direction. The heat-absorbing sealing tool may be provided with a second groove portion corresponding to the shape of the electrode lead.

[0027] According to the first embodiment of the present invention, the second groove may be recessed from one end of the heat-absorbing sealing tool in a central section in a width direction toward the other end in a height direction. The length of the second groove in the width direction may correspond to the width of the electrode lead, and the depth of the second groove may correspond to the thickness of the electrode lead or half of the thickness of the electrode lead.

[0028] The heat-radiating seal tool and the heat-absorbing seal tool may be arranged side by side along the length direction. In this case, one heat-absorbing seal tool may be provided for each of the seal tool assemblies, or two or more heat-absorbing seal tools may be provided for each of the seal tool assemblies. When one heat-absorbing seal tool is provided for each of the seal tool assemblies, it may be located inside the heat-radiating seal tool in the length direction. When two heat-absorbing seal tools are provided for each of the seal tool assemblies, one may be located outside and one may be located inside the heat-radiating seal tool in the length direction.

[0029] The heat absorption / dissipation device may be interposed between the heat-dissipating seal tool and the heat-absorbing seal tool, and may dissipate heat from the heat-dissipating seal tool and absorb heat from the heat-absorbing seal tool. For example, the heat absorption / dissipation device may be interposed between the heat-dissipating seal tool and the heat-absorbing seal tool such that, when a voltage is applied, heat is dissipated from one side of the heat absorption / dissipation device and heat is absorbed from the other side of the heat absorption / dissipation device, and the one side of the heat absorption / dissipation device is in contact with the heat-dissipating seal tool and the other side is in contact with the heat-absorbing seal tool.

[0030] The heat absorbing and dissipating devices may be provided in a plurality in contact with the respective broad surfaces of the heat dissipating sealing tool and the heat absorbing sealing tool. Specifically, the heat absorbing and dissipating devices may be provided in a lattice pattern in contact with the surfaces of the heat dissipating sealing tool and the heat absorbing sealing tool in a direction intersecting the sealing direction.

[0031] According to a first embodiment of the present invention, the heat absorption and dissipation device may be a thermoelectric element that dissipates heat from one side and absorbs heat from the other side when a DC voltage is applied. A thermoelectric element is a type of semiconductor element that is manufactured by connecting multiple pairs of P-type and N-type semiconductors electrically in series and thermally in parallel, and can maintain a constant temperature difference between one side and the other side when a constant DC voltage is applied.

[0032] The sealing tool assembly may include a heat insulating plate interposed in a portion of the space between the heat dissipation sealing tool and the heat absorption sealing tool where the heat absorption / dissipation device is not provided, and the heat insulating plate may be made of a heat insulating material.

[0033] According to Example 1 of the present invention, the insulating plate may be a plate made of insulating material interposed between the heat dissipation seal tool and the heat absorption seal tool, and may have a through hole into which the heat absorption and dissipation device can be attached.

[0034] The sealing tool assembly may include a pair of heat insulating frames that respectively house the sealing tool assemblies, and the heat insulating frames may cover five sides of each sealing tool assembly except for one or the other of the sides in a height direction toward the first seal portion.

[0035] [Example 2] The second embodiment of the present invention can be applied to a sealing device that fusion-seals a first seal portion that is provided at one widthwise end of a pouch included in a pouch-type battery cell and extends along the length of the pouch. The battery cell may include an electrode lead that extends from inside the pouch and protrudes through the first seal portion.

[0036] The heat-dissipating seal tool may be formed to extend along the length direction.

[0037] The heat-absorbing sealing tool may be formed to extend along the length.

[0038] The heat-radiating seal tool and the heat-absorbing seal tool may be arranged side by side in the width direction. In this case, one heat-absorbing seal tool may be provided for each of the seal tool assemblies, or two or more heat-absorbing seal tools may be provided for each of the seal tool assemblies. When one heat-absorbing seal tool is provided for each of the seal tool assemblies, it may be arranged inside the heat-radiating seal tool in the width direction. When two heat-absorbing seal tools are provided for each of the seal tool assemblies, one may be arranged outside and one may be arranged inside the heat-radiating seal tool in the width direction.

[0039] The heat absorption / dissipation device may be interposed between the heat-dissipating seal tool and the heat-absorbing seal tool, and may dissipate heat from the heat-dissipating seal tool and absorb heat from the heat-absorbing seal tool. For example, the heat absorption / dissipation device may be interposed between the heat-dissipating seal tool and the heat-absorbing seal tool such that, when a voltage is applied, heat is dissipated from one side of the heat absorption / dissipation device and heat is absorbed from the other side of the heat absorption / dissipation device, and the one side of the heat absorption / dissipation device is in contact with the heat-dissipating seal tool and the other side is in contact with the heat-absorbing seal tool.

[0040] The heat absorbing and dissipating devices may be provided in a plurality in contact with the respective broad surfaces of the heat dissipating sealing tool and the heat absorbing sealing tool. Specifically, the heat absorbing and dissipating devices may be provided in a lattice pattern in contact with the surfaces of the heat dissipating sealing tool and the heat absorbing sealing tool in a direction intersecting the sealing direction.

[0041] According to a second embodiment of the present invention, the heat absorption and dissipation device may be a thermoelectric element that dissipates heat from one side and absorbs heat from the other side when a DC voltage is applied. A thermoelectric element is a type of semiconductor element that is manufactured by connecting multiple pairs of P-type and N-type semiconductors electrically in series and thermally in parallel, and can maintain a constant temperature difference between one side and the other side when a constant DC voltage is applied.

[0042] The sealing tool assembly may include a heat insulating plate interposed in a portion of the space between the heat dissipation sealing tool and the heat absorption sealing tool where the heat absorption / dissipation device is not provided, and the heat insulating plate may be made of a heat insulating material.

[0043] According to a second embodiment of the present invention, the insulating plate may be a plate made of insulating material interposed between the heat dissipation seal tool and the heat absorption seal tool, and may have a through hole into which the heat absorption and dissipation device can be attached.

[0044] The sealing tool assembly may include a pair of heat insulating frames that respectively house the sealing tool assemblies, and the heat insulating frames may cover five sides of each sealing tool assembly except for one or the other of the sides in a height direction toward the first seal portion. [Effects of the Invention]

[0045] The present invention can provide a sealing device structure in which, when a heat-dissipating sealing tool heats the sealing portion, a heat-absorbing sealing tool absorbs heat from the remainder of the pouch excluding the sealing portion, thereby preventing heat transfer to parts other than the sealing portion, preventing damage to the insulating layer, preventing defects in the battery cells, and improving performance.

[0046] The present invention also provides a sealing device structure that has a simple structure that uses a thermoelectric element to simultaneously heat to 150 degrees Celsius or higher and cool to below room temperature simply by applying voltage, and that transfers the thermal energy absorbed by the heat-absorbing sealing tool directly to the heat-dissipating sealing tool, thereby providing a sealing device structure with excellent thermal energy efficiency.

[0047] The sealing device according to Example 2 of the present invention can concentrate heating and sealing only on a desired area by arranging heat-absorbing sealing tools on both sides of a heat-radiating sealing tool.

[0048] Another advantage of the present invention is that the front of the heat-dissipating sealing tool, excluding the sealing portion side, is covered by the heat-absorbing sealing tool, the heat-insulating plate, and the heat-insulating frame, thereby providing a sealing device structure that minimizes heat loss.

[0049] Another advantage of the present invention is that a plurality of heat absorbing and dissipating devices are provided in contact with the wide surfaces of the heat dissipating sealing tool and the heat absorbing sealing tool, thereby providing a sealing device structure that can heat and cool quickly and maintain a constant temperature.

[0050] In addition to the above, the present invention can achieve various other effects, which will be explained in each embodiment, or explanations of effects that can be easily inferred by ordinary engineers will be omitted. [Brief explanation of the drawings]

[0051] [Figure 1] FIG. 1 is a perspective view showing the structure of a pouch-type battery cell. [Figure 2] FIG. 2 is a cross-sectional view showing the first seal part of a pouch-type battery cell. [Figure 3] FIG. 2 is an enlarged cross-sectional view showing the structure of the pouch insulating layer. [Figure 4] 1 is a diagram showing the structure and arrangement of a typical sealing device. [Figure 5] 1 is a diagram showing the structure and arrangement of a typical sealing device. [Figure 6] FIG. 5 is a cross-sectional view showing how the sealing device of FIG. 4 seals a pouch. [Figure 7] FIG. 1 is an exploded perspective view showing the structure of a sealing tool assembly according to a first embodiment of the present invention. [Figure 8] 1 is a perspective view showing the structure of a sealing tool assembly according to a first embodiment of the present invention. [Figure 9] 1A and 1B are diagrams illustrating the structure of a thermoelectric element and the heating and cooling action of the thermoelectric element according to Example 1 of the present invention. [Figure 10] 1A and 1B are diagrams illustrating the structure of a thermoelectric element and the heating and cooling action of the thermoelectric element according to Example 1 of the present invention. [Figure 11] 1 is a diagram showing a state in which a sealing tool assembly is housed in a heat insulating frame according to a first embodiment of the present invention. [Figure 12] 1 is a diagram showing the arrangement of a sealing device according to a first embodiment of the present invention. [Figure 13] 1 is a cross-sectional view showing a state in which the sealing device according to the first embodiment of the present invention seals a pouch. [Figure 14] FIG. 3 is a diagram showing heat transfer when the sealing device according to the first embodiment of the present invention seals a pouch. [Figure 15] FIG. 10 is an exploded perspective view showing the structure of a sealing tool assembly according to a second embodiment of the present invention. [Figure 16] FIG. 10 is a perspective view showing the structure of a sealing tool assembly according to a second embodiment of the present invention. [Figure 17] 10 is a diagram showing how a sealing tool assembly is housed in a heat insulating frame according to a second embodiment of the present invention. FIG. [Figure 18] FIG. 10 is a diagram showing the arrangement of a sealing device according to a second embodiment of the present invention. [Figure 19] FIG. 10 is a cross-sectional view showing how a sealing device according to a second embodiment of the present invention seals a pouch. DETAILED DESCRIPTION OF THE INVENTION

[0052] The above-mentioned objects, features, and advantages will be described in detail below with reference to the accompanying drawings, so that those skilled in the art can easily implement the technical concept of the present invention. In describing the present invention, if a detailed description of known technologies related to the present invention is deemed to obscure the gist of the present invention, the detailed description will be omitted. Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The same reference numerals in the drawings are used to indicate the same or similar components.

[0053] Although terms such as "first" and "second" are used to indicate various components, it is understood that these components are not limited by these terms. These terms are used merely to distinguish one component from another, and unless otherwise specified, a first component may also be a second component.

[0054] Throughout the specification, unless otherwise specified, each element may be singular or plural.

[0055] Hereinafter, when an arbitrary structure is arranged "on top (or bottom)" of a component or "above (or below)" a component, it means that the arbitrary structure is not only arranged in contact with the upper surface (or lower surface) of the component, but also that other structures may be interposed between the component and the arbitrary structure arranged above (or below) the component.

[0056] Furthermore, when a component is described as being "coupled," "coupled," or "connected" to another component, it should be understood that the components may be directly coupled or connected to each other, but that other components may be "intervening" between the components, or that each component may be "coupled," "coupled," or "connected" via other components.

[0057] As used herein, singular expressions include plural expressions unless the context clearly indicates otherwise. Terms such as "comprise" or "include" in this application should not be interpreted as including all of the multiple components or multiple steps described in the specification, but should be interpreted as meaning that some of the components or some of the steps may not be included, or that additional components or steps may be included.

[0058] In the entire specification, "A and / or B" means A, B or A and B unless otherwise specified, and "C to D" means C or more and D or less unless otherwise specified.

[0059] First, an example of the structure of a pouch-type battery cell that can be sealed by the sealing device of the present invention will be described below with reference to the drawings.

[0060] Fig. 1 is a perspective view showing the structure of a pouch-type battery cell, and Fig. 2 is a cross-sectional view showing a first seal of the pouch-type battery cell. Referring to these drawings, the pouch-type battery cell 1 may include an electrode assembly 11, an electrode tab 12, an electrode lead 13, and a pouch 14.

[0061] The electrode assembly 11 may be formed by stacking a plurality of electrodes with a separator interposed therebetween. The electrodes may include a positive electrode and a negative electrode. That is, the electrode assembly 11 may be formed by stacking a plurality of positive electrodes and negative electrodes alternately with a separator interposed therebetween.

[0062] The electrode tab 12 may extend from each electrode of the electrode assembly 11. The electrode tabs 12 extending from the electrodes may be stacked with the same poles to form one tab. That is, the positive and negative electrodes may be connected in parallel with the same poles to form the electrode tab 12.

[0063] The pouch 14 may be made of a metal sheet material. The pouch 14 may accommodate the electrode assembly 11 while surrounding it. The pouch 14 may be sealed at first seal portions 143a extending along the width direction at both ends of the pouch 14 in the longitudinal direction, and at a second seal portion 143b extending along the length direction at one end of the pouch 14 in the width direction. The seals may be formed by fusion welding. The sealing method of the pouch 14 will be described later.

[0064] The electrode lead 13 may be connected to the electrode tab 12. The connection may be by welding. The welding may be by various methods such as ultrasonic welding, resistance welding, laser welding, etc. The electrode lead 13 may extend along the length direction and protrude to the outside of the pouch 14 through the first seal portion 143a.

[0065] In this case, a lead film 131 may be provided on the electrode lead 13. The lead film 131 may be provided at a position corresponding to the first seal portion 143a and may be interposed between the double pouch 14. The lead film 131 may be made of a fusible material such as a thermoplastic synthetic resin. The lead film 131 may be made of an electrically insulating material. For example, the lead film 131 may be made of a polypropylene material.

[0066] 3 is an enlarged cross-sectional view showing the structure of the pouch insulating layer. Referring to this, the pouch 14 may include a metal layer 141 and an insulating layer 142. The insulating layer 142 may include an inner insulating layer 142a and an outer insulating layer 142b.

[0067] The metal layer 141 may be made of a metal sheet material or an electrically conductive metal material, for example, aluminum.

[0068] The insulating layer 142 may be made of an electrically insulating material, for example, an electrically insulating synthetic resin.

[0069] The inner insulating layer 142a may be coated on the inner surface of the metal layer 141. The inner insulating layer 142a may be made of a fusible material such as a thermoplastic synthetic resin. For example, the inner insulating layer 142a may be made of a polypropylene material. The inner insulating layer 142a may serve to insulate the electrode assembly 11, the electrode tab 12, and the electrode lead 13 from the metal layer 141.

[0070] The outer insulating layer 142b may be coated on the outer surface of the metal layer 141. The outer insulating layer 142b may be made of the same material as the inner insulating layer 142a. The outer insulating layer 142b may serve to insulate the metal layer 141 from the outside of the pouch 14. For example, when a plurality of the battery cells 1 are stacked to form a battery module, the outer insulating layer 142b may serve to insulate the battery cell 1 from each pouch metal layer of an adjacent battery cell.

[0071] The first sealing portion 143a may be fusion sealed. The fusion sealing can be achieved by fusing the internal insulating layer 142a and the lead film 131. Specifically, the sealing between the double pouches 14 may be achieved by fusing the internal insulating layers 142a, and the sealing between the pouches 14 and the electrode leads 13 may be achieved by fusing the lead films 131. As a result, the pouches 14 may be sealed in a state where the metal layers 141 are insulated from each other, and the electrode leads 13 may also be sealed in a state where they are insulated from the metal layers of the pouches 14.

[0072] If the lead film 131 and the inner insulating layer 142a are both made of polypropylene material, the melting point of polypropylene is approximately 160 degrees Celsius, so in order to seal the first sealing portion 143a, a sealing device that can heat and pressurize the first sealing portion 143a to 160 degrees Celsius or higher is required.

[0073] The second sealing portion 143b may be fusion sealed. The fusion sealing can be performed by fusing the inner insulating layer 142a. As a result, the pouch 14 may be sealed in a state where the metal layers 141 are insulated from each other.

[0074] If the inner insulating layer 142a is made of polypropylene, the melting point of polypropylene is approximately 160 degrees Celsius. Therefore, in order to seal the second sealing portion 143b, a sealing device capable of heating and pressurizing the second sealing portion 143b to 160 degrees Celsius or higher is required.

[0075] The structure of a commonly used sealing device and its problems will be described below. Although the first sealing portion 143a will be exemplified below, the structure and problems are the same for the second sealing portion 143b.

[0076] 4 and 5 show the structure and arrangement of a conventional sealing device. Referring to these drawings, the conventional sealing device 2 includes a sealing tool 21, a sealing block 22, a heat rod 23, and an insulating frame 24.

[0077] The sealing tool 21 is made of a metal material and is formed to extend in the width direction. A groove 211 having a width corresponding to the width of the electrode lead 13 and a depth corresponding to the thickness of the electrode lead 13 is provided along a central section of the sealing tool 21 in the width direction.

[0078] The seal block 22 is connected to the sealing tool 21. The seal block 22 is made of a metal material and is formed to extend in the width direction. A first hole 221 is formed in the seal block 22, passing through the seal block 22 in the width direction.

[0079] The heat insulating frame 24 is a frame that is open at one end in the height direction and accommodates the seal block 22. The heat insulating frame 24 is made of a heat insulating material. Second holes 241 corresponding to the first holes 221 are formed at both ends in the width direction of the heat insulating frame 24.

[0080] The heat rod 23 is inserted into the first hole 221 through the second hole 241. The heat rod 23 may be heated, and the heat rod 23 may heat the seal block 22 and the seal tool 21.

[0081] The sealing devices 2 are formed in a pair on both sides in the height direction, facing each other with the sealing tools 21 facing inward. When sealing the pouch 14, the sealing devices 2 are arranged on both sides in the height direction of the first sealing portion 143a.

[0082] 6 is a cross-sectional view showing how the sealing device of FIG. 4 seals a pouch. Referring to this, the heated sealing tool 21 heats and pressurizes the first sealing portion 143a, causing the lead film 131 and the inner insulating layer 142a to melt, re-solidify, and fuse together, thereby sealing the pouch 14 and the electrode lead 13.

[0083] At this time, heat transferred from the sealing tool 21 to the pouch 14 may be conducted along the metal layer 141 to other portions of the pouch 14 other than the first seal portion 143a. Furthermore, heat is transferred from the sealing tool 21 to the pouch 14 by radiation and convection. The conductive, radiant, and convective heat may also heat portions of the pouch 14 other than the first seal portion 143a, causing the inner insulating layer 142a and / or the outer insulating layer 142b to melt and become damaged. If the insulating layer 142 is damaged, the performance of the battery cell 1 may be reduced, leading to a short circuit and a risk of fire.

[0084] Furthermore, the heat transferred from the sealing tool 21 to the portion other than the first sealing portion 143a cannot be further recovered and is lost as it is, thereby reducing the energy efficiency of the sealing device 2.

[0085] In this regard, the present invention provides a sealing device structure including a pair of sealing tool assemblies including a heat-radiating sealing tool, a heat-absorbing sealing tool, and a heat-absorbing and heat-radiating device.

[0086] Preferred embodiments of the present invention will now be described with reference to the accompanying drawings.

[0087] [Example 1] The sealing device according to the first embodiment of the present invention can be used to seal the first sealing portion.

[0088] 7 and 8 are exploded and perspective views showing the structure of a seal tool assembly according to a first embodiment of the present invention. Referring to these drawings, a seal device according to the present invention may include a pair of seal tool assemblies including a heat-dissipating seal tool 31, a heat-absorbing seal tool 32, and a heat-absorbing and dissipating device 33.

[0089] The heat-dissipation seal tool 31 may be made of a metal material and may be formed to extend in the width direction. The heat-dissipation seal tool 31 may be provided with a first groove 311 corresponding to the shape of the electrode lead 13. The first groove 311 may be recessed toward the other side in the height direction over a portion of the width center of one end of the height direction of the heat-dissipation seal tool. The length of the first groove 311 in the width direction may correspond to the width of the electrode lead 13, and the depth may correspond to the thickness of the electrode lead 13 or half of the thickness.

[0090] The heat-absorbing sealing tool 32 may be made of a metal material and may be formed to extend in the width direction. The heat-absorbing sealing tool 32 may be provided with a second groove 321 corresponding to the shape of the electrode lead 13. The second groove 321 may be recessed toward the other side in the height direction over a portion of the width center of one end of the heat-absorbing sealing tool in the height direction. The length of the second groove 321 in the width direction may correspond to the width of the electrode lead 13, and the depth may correspond to the thickness of the electrode lead 13 or half of the thickness.

[0091] The heat-absorbing seal tool 32 may be arranged in parallel with the heat-dissipating seal tool 31 in the longitudinal direction. In this case, one or two heat-absorbing seal tools 32 may be included in each seal tool assembly. When one heat-absorbing seal tool 32 is provided in each seal tool assembly, the heat-absorbing seal tool 32 may be located inside the heat-dissipating seal tool 31 in the longitudinal direction. When two heat-absorbing seal tools 32 are provided in each seal tool assembly, the heat-absorbing seal tool 32 may be located on both sides of the heat-dissipating seal tool 31 in the longitudinal direction.

[0092] The heat absorption and radiation device 33 may be interposed between the heat-radiating seal tool 31 and the heat-absorbing seal tool 32. The heat absorption and radiation device 33 may have one surface that radiates heat and the other surface that absorbs heat. The heat absorption and radiation device 33 may be provided so that one surface contacts the heat-radiating seal tool 31 and the other surface contacts the heat-absorbing seal tool 32. As a result, the heat absorption and radiation device 33 may heat the heat-radiating seal tool 31 and cool the heat-absorbing seal tool 32. Preferably, when a voltage is applied to the heat absorption and radiation device 33, one surface radiates heat and the other surface absorbs heat, thereby heating the heat-radiating seal tool 31 and cooling the heat-absorbing seal tool 32.

[0093] A plurality of the heat absorbing and dissipating devices 33 may be provided in contact with each of the wide surfaces of the heat-dissipating sealing tool 31 and the heat-absorbing and sealing tool 32. Specifically, a plurality of the heat absorbing and dissipating devices 33 may be provided in contact with the surfaces of the heat-dissipating and sealing tool 31 and the heat-absorbing and sealing tool 32 in a lattice pattern on the sides of the tools in a direction intersecting the sealing direction. By providing a plurality of the heat absorbing and dissipating devices 33 in contact with the heat-dissipating and sealing tool 31 and the heat-absorbing and sealing tool 32, heating and cooling can occur quickly and at a high level, and the heating and cooling state can be easily maintained constant.

[0094] The sealing tool assembly may include an insulating plate 34. The insulating plate 34 may be interposed in a portion of the space between the heat-radiating seal tool 31 and the heat-absorbing seal tool 32 where the heat-absorbing and dissipating device 33 is not provided. The insulating plate 34 may be made of an insulating material. The insulating plate 34 may be a plate made of an insulating material interposed between the heat-radiating seal tool 31 and the heat-absorbing seal tool 32 and may have a through-hole into which the heat-absorbing and dissipating device 33 can be attached. By providing the insulating plate 34, heat transfer between the heat-radiating seal tool 31 and the heat-absorbing seal tool 32 occurs only through the portion where the heat-radiating and dissipating device 33 is provided, and thermal energy from the heat-radiating seal tool 31 in other portions is prevented from being transferred to the heat-absorbing seal tool 32.

[0095] 9 and 10 show the structure of a thermoelectric element and the heating and cooling action of the thermoelectric element according to the first embodiment of the present invention. Referring to these drawings, the heat absorption and dissipation device 33 may be a thermoelectric element (Peltier element). A thermoelectric element is a type of semiconductor element that is manufactured by connecting multiple pairs of P-type and N-type semiconductors electrically in series and thermally in parallel, and can maintain a constant temperature difference between one side and the other side when a constant DC voltage is applied.

[0096] The thermoelectric element 33 can maintain a constant temperature difference between the heat-radiating seal tool 31 and the heat-absorbing seal tool 32 by emitting thermal energy absorbed from the heat-absorbing seal tool 32 to the heat-dissipating seal tool 31. When the heat-radiating seal tool 31 and the heat-absorbing seal tool 32 are both at room temperature, if a DC voltage is applied to the thermoelectric element 33, the heat-radiating seal tool 31 may be heated to a temperature above room temperature, and the heat-absorbing seal tool 32 may be heated to a temperature below room temperature. In this case, when the heat-absorbing seal tools 32 are installed on both sides of the heat-radiating seal tool 31, the thermal energy gained by the heat-radiating seal tool 31 may be twice the thermal energy lost by each of the heat-absorbing seal tools 32.

[0097] FIG. 11 shows a sealing tool assembly accommodated in an insulating frame according to a first embodiment of the present invention. Referring to this figure, the sealing device may include a pair of insulating frames 35, each accommodating a pair of the sealing tool assemblies. The insulating frame 35 may be entirely made of an insulating material, or each of its surfaces, particularly its vertical surfaces, may be provided with an insulating layer covering it internally or externally. Preferably, the insulating frame 35 covers all five sides of the sealing tool assembly, excluding one or both sides in the height direction toward the first sealing portion of the sealing tool assembly. Compared to a typical sealing device in which a sealing tool is fixed to a seal block and an insulating frame covers only the seal block, the sealing device according to this embodiment is configured to cover the sealing tool assembly itself, thereby more effectively reducing heat loss due to radiant heat and convective heat generated horizontally from the sealing tool assembly, thereby achieving excellent energy efficiency.

[0098] 12 shows the arrangement of a sealing device according to a first embodiment of the present invention. Referring to this, the sealing device is formed as a pair including a pair of the sealing tool assemblies and a pair of the insulating frames 35 that respectively accommodate the pair of sealing tool assemblies, and the pair of sealing devices may be located on opposite sides of the first sealing portion 143a in the height direction. When the first groove portion 311 and / or the second groove portion 321 are provided in the heat-dissipating sealing tool 31 and / or the heat-absorbing sealing tool 32, each of the sealing tool assemblies may be arranged such that the first groove portion 311 and / or the second groove portion 321 faces inward in the height direction where the first sealing portion 143a is provided.

[0099] 13 is a cross-sectional view showing a state in which the sealing device according to the first embodiment of the present invention seals a pouch. Referring to this figure, the heat-dissipating sealing tool 31 applies pressure and heat to the first sealing portion 143a from both sides in the height direction, thereby fusing the inner insulating layer 142a and the lead film 131 and sealing the first sealing portion 143a. At this time, the heat-absorbing sealing tool 32 contacts the pouch 14 on both sides in the length direction of the first sealing portion 143a, thereby cooling the contacting portions and preventing damage to the insulating layer 142 other than the first sealing portion 143a.

[0100] 14 shows heat transfer when the sealing apparatus according to the first embodiment of the present invention seals a pouch. When a predetermined DC voltage is applied to the thermoelectric element 33, the thermoelectric element 33 absorbs heat energy from the heat-absorbing seal tool 32 and dissipates it to the heat-dissipating seal tool 31, thereby maintaining a constant temperature difference between the heat-absorbing seal tool 32 and the heat-dissipating seal tool 31. As a result, the heat-dissipating seal tool 31 is heated to a temperature above room temperature, and the heat-absorbing seal tool 32 is cooled to a temperature below room temperature. Because heat transfer from the heat-dissipating seal tool 31 to the heat-absorbing seal tool 32 by conduction, radiation, and convection is blocked by the insulating plate 34, only one-way heat transfer from the heat-absorbing seal tool 32 to the heat-dissipating seal tool 31 occurs between the heat-dissipating seal tool 31 and the heat-absorbing seal tool 32. For example, even if there is heat energy transferred from the heat-dissipating seal tool 31 to the heat-absorbing seal tool 32, this can be further transferred back to the heat-dissipating seal tool 31 via the thermoelectric element 33. In addition, the heat insulating plate 34 and the heat-absorbing seal tool 32 can also block heat loss from the heat-dissipating seal tool 31 to the outside due to conduction, radiation, and convection.

[0101] The heat energy absorbed by the heat-dissipating sealing tool 31 can be conducted to the internal insulating layer 142a and the lead film 131 provided inside the first sealing portion 143a through the surface of the first sealing portion 143a that the heat-dissipating sealing tool 31 contacts. The heat energy remaining after melting the internal insulating layer 142a and the lead film 131 is conducted to both ends of the first sealing portion 143a in the longitudinal direction through the pouch 14, and the heat-absorbing sealing tool 32 can absorb the conducted heat energy. That is, the heat-absorbing sealing tool 32 can reabsorb the residual heat conducted from the heat-dissipating sealing tool 31 to the first sealing portion 143a and melting the lead film 131 and the internal insulating layer 142a, and resupply the reabsorbed heat to the heat-dissipating sealing tool 31 via the thermoelectric element 33. In this case, the heat-absorbing sealing tool 32 can absorb heat energy not only from the pouch 14 but also from the external air and resupply it to the thermoelectric element 33.

[0102] In short, the sealing device according to Example 1 of the present invention can reabsorb and utilize the remaining energy used to seal the first sealing portion 143a, and the insulating plate 34, the heat-absorbing sealing tool 32, and the insulating frame 35 block heat loss from the heat-dissipating sealing tool 31 to the outside due to conduction, radiation, and convection, resulting in high energy efficiency. At the same time, it can target and seal only the desired area, and the surrounding area can be cooled to below room temperature, thereby reducing the risk of damage to the surrounding area.

[0103] [Example 2] The sealing device according to the second embodiment of the present invention can be used to seal the second sealing portion 143b. In the following, the parts of this embodiment that are not specifically described are the same as those of the first embodiment.

[0104] 15 and 16 are exploded and perspective views showing the structure of a seal tool assembly according to a second embodiment of the present invention. Referring to these drawings, a seal device according to the present invention may include a pair of seal tool assemblies including a heat-dissipating seal tool 41, a heat-absorbing seal tool 42, and a heat-absorbing and dissipating device 43.

[0105] The heat-dissipating seal tool 41 may be made of a metal material and may be formed to extend in the length direction.

[0106] The heat-absorbing sealing tool 42 may be made of a metal material and may be formed to extend in the length direction.

[0107] The heat-absorbing seal tool 42 may be arranged next to the heat-radiating seal tool 41 in the width direction. In this case, one or two heat-absorbing seal tools 42 may be included in each seal tool assembly. When one heat-absorbing seal tool 42 is provided in each seal tool assembly, the heat-absorbing seal tool 42 may be located inside the heat-radiating seal tool 41 in the width direction. When two heat-absorbing seal tools 42 are provided in each seal tool assembly, the heat-absorbing seal tool 42 may be located on both sides of the heat-radiating seal tool 41 in the width direction.

[0108] The heat absorption and radiation device 43 may be interposed between the heat-radiating seal tool 41 and the heat-absorbing seal tool 42. The heat absorption and radiation device 43 may have one surface that radiates heat and the other surface that absorbs heat. The heat absorption and radiation device 43 may be provided so that one surface contacts the heat-radiating seal tool 41 and the other surface contacts the heat-absorbing seal tool 42. As a result, the heat absorption and radiation device 43 may heat the heat-radiating seal tool 41 and cool the heat-absorbing seal tool 42. Preferably, when a voltage is applied to the heat absorption and radiation device 43, one surface radiates heat and the other surface absorbs heat, thereby heating the heat-radiating seal tool 41 and cooling the heat-absorbing seal tool 42. The heat absorption and radiation device 43 may be a thermoelectric element (Peltier element).

[0109] A plurality of the heat absorbing and dissipating devices 33 may be provided in contact with each of the wide surfaces of the heat-dissipating sealing tool 31 and the heat-absorbing sealing tool 32. Specifically, a plurality of the heat absorbing and dissipating devices 33 may be provided in contact with the surfaces of the heat-dissipating sealing tool 31 and the heat-absorbing sealing tool 32 in a lattice pattern on the sides of the sealing tool 31 and the heat-absorbing sealing tool 32 in a direction intersecting the sealing direction. By providing a plurality of the heat absorbing and dissipating devices 33 in contact with the heat-dissipating sealing tool 31 and the heat-absorbing sealing tool 32, heating and cooling can occur quickly and at a high level, and the heating and cooling state can be easily maintained constant.

[0110] The sealing tool assembly may include an insulating plate 44. The insulating plate 44 may be interposed in a portion of the space between the heat-radiating seal tool 41 and the heat-absorbing seal tool 42 where the heat-absorbing and dissipating device 43 is not provided. The insulating plate 44 may be made of an insulating material. The insulating plate 44 may be a plate made of an insulating material interposed between the heat-radiating seal tool 41 and the heat-absorbing seal tool 42 and may have a through-hole through which the heat-absorbing and dissipating device 43 can be attached. By providing the insulating plate 44, heat transfer between the heat-radiating seal tool 41 and the heat-absorbing seal tool 42 occurs only through the portion where the heat-radiating and dissipating device 43 is provided, and thermal energy from the heat-radiating seal tool 41 in other portions is prevented from being transferred to the heat-absorbing seal tool 42.

[0111] FIG. 17 shows a sealing tool assembly accommodated in an insulating frame according to a second embodiment of the present invention. Referring to this figure, the sealing device may include a pair of insulating frames 45, each accommodating a pair of the sealing tool assemblies. The insulating frame 45 may be entirely made of an insulating material, or each of its surfaces, particularly its vertical surfaces, may be provided with an insulating layer covering it internally or externally. Preferably, the insulating frame 45 covers all five sides of the sealing tool assembly, excluding one or both sides in the height direction toward the first sealing portion of the sealing tool assembly. Compared to a typical sealing device in which a sealing tool is fixed to a seal block and an insulating frame covers only the seal block, the sealing device according to this embodiment is configured to cover the sealing tool assembly itself. This effectively reduces heat loss due to radiant heat and convective heat generated horizontally from the sealing tool assembly, thereby improving energy efficiency.

[0112] 18 shows the arrangement of a sealing device according to a second embodiment of the present invention. Referring to this, the sealing device is formed as a pair including a pair of the sealing tool assemblies and a pair of the insulating frames 45 that respectively accommodate the sealing tool assemblies, and the pair of sealing devices may be located on both sides of the second sealing portion 143b in the height direction.

[0113] 19 is a cross-sectional view showing a state in which the sealing device according to Example 2 of the present invention seals a pouch. Referring to this, the sealing device allows the heat-dissipating sealing tool 41 to apply pressure and heat to the second sealed portion 143b from both sides in the height direction, thereby fusing the inner insulating layer 142a and sealing the second sealed portion 143b. At this time, the heat-absorbing sealing tool 42 contacts the pouch 14 on both sides in the width direction of the second sealed portion 143b, thereby cooling the contacting portions and preventing damage to the insulating layer 142 in the area other than the second sealed portion 143b.

[0114] It should be understood that the above-described embodiments are illustrative in all respects and are not limiting, and the scope of the present invention is defined by the following claims rather than the above detailed description. All modifications and variations within the meaning and scope of the following claims, as well as equivalent concepts, should be construed as being included within the scope of the present invention.

[0115] Although the present invention has been described above with reference to illustrative drawings, the present invention is not limited to the embodiments and drawings disclosed in this specification, and various modifications may be made by those skilled in the art within the scope of the technical concept of the present invention. Furthermore, even if the effects of the configuration of the present invention are not explicitly described in the above description of the embodiments of the present invention, it is natural that the effects that can be predicted by the configuration should also be recognized. [Explanation of symbols]

[0116] 1 battery cell 11 Electrode assembly 12 Electrode tab 13 Electrode Lead 131 Lead Film 14 pouches 141 Metal layer 142 Insulating layer 142a Inner insulating layer 142b Outer insulating layer 143 Seal part 143a First seal part 143b Second seal part 2 Sealing device 1 21 Sealing Tool 211 Groove 22 Seal Block 221 Hole 1 23 Heat Rod 24 Insulation Frame 241 Hole 2 3 Sealing device 2 31 Heat dissipation seal tool 311 First groove 32 Heat-absorbing sealing tool 321 Second groove 33 Heat absorption / dissipation device (Peltier element) 34 Heat insulating plate 35 Insulation Frame 4 Sealing device 3 41 Heat dissipation seal tool 42 Heat-absorbing sealing tool 43 Heat absorption / dissipation device (Peltier element) 44 Insulation Plate 45 Insulation Frame X length direction Y width direction Z height direction / thickness direction

Claims

1. A sealing device that fusion-seals first seal portions that are provided at both longitudinal ends of a pouch included in a pouch-type battery cell and extend along the width direction, a heat-dissipating seal tool formed to extend along the width direction; a heat-absorbing seal tool formed to extend along the width direction and juxtaposed with the heat-radiating seal tool along the length direction; and a heat absorbing / radiating device interposed between the heat-radiating seal tool and the heat-absorbing seal tool; and a pair of seal tool assemblies disposed one on each side in the height direction of the first seal part, the heat absorbing and dissipating device radiates heat to the heat-dissipating seal tool and absorbs heat to the heat-absorbing seal tool; Sealing device.

2. The heat absorption and dissipation device is When an electric current is applied, heat is released from one side and absorbed from the other side. One surface of the seal tool is in contact with the heat-radiating seal tool, and the other surface of the seal tool is in contact with the heat-absorbing seal tool, and the seal tool is interposed between the heat-radiating seal tool and the heat-absorbing seal tool. The sealing device according to claim 1 .

3. The heat absorption / dissipation device is a Peltier element that dissipates heat from one side and absorbs heat from the other side when an electric current is applied. The sealing device according to claim 2 .

4. the battery cell includes an electrode lead extending from inside the pouch and protruding through the first seal portion; The heat dissipation seal tool is provided with a first groove portion corresponding to the shape of the electrode lead. The sealing device according to claim 1 .

5. the heat-absorbing sealing tool is provided with a second groove portion corresponding to the shape of the electrode lead; The sealing device according to claim 4.

6. the heat-absorbing seal tool is provided for each of the seal tool assemblies and is positioned inward in the longitudinal direction relative to the heat-dissipating seal tool; The sealing device according to claim 1 .

7. Two heat-absorbing seal tools are provided for each seal tool assembly, one on the outer side and one on the inner side in the length direction of the heat-radiating seal tool. The sealing device according to claim 1 .

8. the seal tool assembly includes a heat insulating plate interposed in a portion of a space between the heat radiation seal tool and the heat absorption seal tool where the heat absorption / radiation device is not provided; The sealing device according to claim 1 .

9. a pair of insulating frames each housing the sealing tool assembly; A sealing device according to any one of claims 1 to 8.

10. the heat insulating frame covers five sides of the seal tool assembly except for one or the other in a height direction toward the first seal portion of each of the seal tool assemblies; The sealing device according to claim 9.

11. A sealing device that fusion-seals a second seal portion that is provided at one widthwise end of a pouch included in a pouch-type battery cell and that extends along the lengthwise direction, a heat dissipation seal tool formed extending along the length; a heat-absorbing seal tool formed to extend along the length direction and juxtaposed with the heat-radiating seal tool along the width direction; and a heat absorbing / radiating device interposed between the heat-radiating seal tool and the heat-absorbing seal tool; and a pair of seal tool assemblies disposed one on each side in the height direction of the second seal part, the heat absorbing and dissipating device radiates heat to the heat-dissipating seal tool and absorbs heat to the heat-absorbing seal tool; Sealing device.

12. The heat absorption and dissipation device is When an electric current is applied, heat is released from one side and absorbed from the other side. One surface of the seal tool is in contact with the heat-radiating seal tool, and the other surface of the seal tool is in contact with the heat-absorbing seal tool, and the seal tool is interposed between the heat-radiating seal tool and the heat-absorbing seal tool. The sealing device of claim 11.

13. The heat absorption / dissipation device is a Peltier element that dissipates heat from one side and absorbs heat from the other side when an electric current is applied. The sealing device of claim 12.

14. the heat-absorbing seal tool is provided for each of the seal tool assemblies and is positioned inward in the width direction relative to the heat-radiating seal tool; The sealing device of claim 11.

15. Two heat-absorbing seal tools are provided for each seal tool assembly, one on the outer side and one on the inner side in the width direction of the heat-radiating seal tool. The sealing device of claim 11.

16. the seal tool assembly includes a heat insulating plate interposed in a portion of a space between the heat radiation seal tool and the heat absorption seal tool where the heat absorption / radiation device is not provided; The sealing device of claim 11.

17. a pair of insulating frames each housing the sealing tool assembly; 17. A sealing device according to any one of claims 11 to 16.

18. the heat insulating frame covers five sides of the seal tool assembly except for one or the other in a height direction toward the second seal portion of each of the seal tool assemblies; 18. The sealing device of claim 17.

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