Battery pack

Abstract

A battery pack including a lower case and an upper case that define an internal space, a plurality of battery cells provided within the internal space, and a pack gasket provided between the lower case and the upper case, the pack gasket including a first surface facing the upper case, a second surface opposite the first surface and facing the lower case, a first side portion facing the internal space, and a second side portion facing the outside of the battery pack, and a battery pack provided with a heat-resistant plastic member at least partially between the first side portion and the second side portion in any cross-section in the width direction is provided.

Description

Technical Field

[0001] The present invention relates to a battery pack, and more specifically, to a battery pack in which safety can be improved by maintaining the sealing performance of a pack gasket even when a flame occurs inside.

[0002] This application claims the benefit of priority based on Korean Patent Application No. 10-2022-0097560 filed on August 4, 2022, and Korean Patent Application No. 10-2023-0043322 filed on April 3, 2023, and all the contents disclosed in the documents of the Korean patent applications are included as part of this specification.

Background Art

[0003] Unlike primary batteries, secondary batteries can be charged and discharged multiple times. Secondary batteries are widely used as an energy source for various wireless devices such as handsets, notebook computers, and wireless vacuum cleaners. In recent years, due to improvements in energy density and economies of scale, the manufacturing cost per unit capacity of secondary batteries has decreased dramatically, and as the driving range of battery electric vehicles (BEVs) has increased to a level equivalent to that of fuel vehicles, the main use of secondary batteries has shifted from mobile devices to mobility.

[0004] The latest trend in the technological development of secondary batteries for mobility is the improvement of energy density and safety. Here, the energy density of a secondary battery is the value obtained by dividing the maximum electrical energy that the secondary battery can store by the mass of the secondary battery. Since the high energy density of a secondary battery directly affects the driving efficiency and driving range of mobility, various studies have been conducted to improve the energy density of secondary batteries.

Summary of the Invention

Problems to be Solved by the Invention

[0005] The technical problem that this invention aims to solve is to provide a battery pack that can improve safety by maintaining the sealing performance of the pack gasket even if a flame occurs inside. [Means for solving the problem]

[0006] To achieve the above technical objectives, the present invention provides a battery pack comprising: a pack case including a lower case and an upper case defining an internal space; a plurality of battery cells provided within the internal space; and a pack gasket provided between the lower case and the upper case, wherein the pack gasket includes a first surface facing the upper case; a second surface opposite the first surface and facing the lower case; a first side facing the internal space; and a second side facing the outside of the pack case, wherein the pack gasket includes at least a portion of a heat-resistant plastic member between the first side and the second side in any cross-section in the width direction.

[0007] In some embodiments, the heat-resistant plastic member extends at least partially along the joint surface between the upper case and the lower case, and the heat-resistant plastic member may be positioned closer to the internal space than the center between the first side and the second side.

[0008] In some embodiments, the pack gasket includes a gasket body and a heat-resistant plastic member, the gasket body includes a storage section, and the heat-resistant plastic member may be placed inside the storage section.

[0009] In some embodiments, the gasket body may include a first portion interposed between the upper case and the lower case, and a second portion extending from the first portion into the internal space and extending along the side walls of the upper case and / or the lower case.

[0010] In some embodiments, the dimensions of the heat-resistant plastic member in the thickness direction of the first portion may be even greater than the thickness of the first portion.

[0011] In some embodiments, the heat-resistant plastic member may be positioned to overlap the first portion over the entire thickness of the first portion.

[0012] In some embodiments, the heat-resistant plastic member may be formed integrally with or integrated with the gasket body. In some embodiments, the heat-resistant plastic member may be integrated with the gasket body using an insert mold method.

[0013] In some embodiments, the heat-resistant plastic member may contain one or more of the following: acrylonitrile resin, acrylic resin, benzimidazole resin, indoline resin, imide resin, amide resin, phenylene oxide resin, butylene terephthalate resin, fluororesin, or copolymers thereof.

[0014] Another aspect of the present invention includes a pack case comprising a lower case and an upper case defining an internal space, a plurality of battery cells provided within the internal space, and a pack gasket provided between the lower case and the upper case, wherein the pack gasket comprises a heat-resistant plastic member and a gasket body extending along the joint surface between the upper case and the lower case, and the heat-resistant plastic member is integrated with the gasket body to provide a battery pack.

[0015] In some embodiments, the gasket body includes a storage section, and the heat-resistant plastic member can be inserted into the storage section.

[0016] In some embodiments, the heat-resistant plastic member may extend at least over the distance between the upper case and the lower case.

[0017] In some embodiments, the heat-resistant plastic member may be interposed at least partially between the upper case and the lower case.

[0018] In some embodiments, at least a portion of the heat-resistant plastic member may protrude from between the upper case and the lower case toward the internal space.

[0019] In some embodiments, the heat-resistant plastic member may not be interposed between the upper case and the lower case. [Effects of the Invention]

[0020] The battery pack of the present invention has the effect of improving safety by maintaining the sealing performance of the pack gasket even if a flame occurs inside.

[0021] The effects that can be obtained from exemplary embodiments of the present invention are not limited to those mentioned above, and other effects not mentioned can be clearly derived and understood by a person of ordinary skill in the art to which the exemplary embodiments of this disclosure belong, from the following description. That is, unintended effects associated with carrying out exemplary embodiments of this disclosure can also be derived by a person of ordinary skill in the art from exemplary embodiments of this disclosure. [Brief explanation of the drawing]

[0022] [Figure 1] This is a perspective view of a battery pack according to an exemplary embodiment. [Figure 2] This is a perspective view showing some elements of a battery pack according to an exemplary embodiment. [Figure 3] Figure 2 is a partial perspective view showing a cross-section of the battery pack in Figure 1, cut along the line III-III'. [Figure 4] This is a cross-sectional perspective view showing the main part of a pack gasket according to one embodiment of the present invention. [Figure 5]FIG. 0 is a partial cross-sectional perspective view showing a cross-section of a battery pack according to another embodiment of the present invention cut along line III-III' of FIG. 2. [Figure 6] FIG. 0 is a partial cross-sectional perspective view showing a cross-section of a battery pack according to another embodiment of the present invention cut along line III-III' of FIG. 2. [Figure 7] FIG. 0 is a partial cross-sectional perspective view showing a cross-section of a battery pack according to another embodiment of the present invention cut along line III-III' of FIG. 2. [Figure 8] FIG. 0 is a partial cross-sectional perspective view showing a cross-section of a battery pack according to another embodiment of the present invention cut along line III-III' of FIG. 2. [Figure 9] FIG. 12 is a partial perspective view of the battery pack 100 of the present embodiment. [Figure 10] FIG. 15 is a partial perspective view of a lower case with a pack gasket having a reinforced corner portion attached thereto.

BEST MODE FOR CARRYING OUT THE INVENTION

[0023] Hereinafter, preferred embodiments of the concept of the present invention will be described in detail with reference to the accompanying drawings. However, embodiments of the concept of the present invention can be deformed into various different forms, and the scope of the concept of the present invention should not be construed as being limited by the embodiments described above. Embodiments of the concept of the present invention are preferably construed as being provided to more fully explain the concept of the present invention to those having average knowledge in the art. The same reference numerals mean the same elements throughout. Further, various elements and regions in the drawings are schematically drawn. Therefore, the concept of the present invention is not limited by the relative sizes or intervals depicted in the attached drawings.

[0024] Terms such as "first," "second," etc., may be used to describe a variety of components, but the components are not limited by these terms. The terms are used solely for the purpose of distinguishing one component from another. For example, without departing from the scope of the concept of the present invention, the first component may be named the second component, and conversely, the second component may be named the first component.

[0025] The terms used in this application are used solely to describe specific embodiments and are not intended to limit the concepts of the invention. A singular expression includes plural expressions unless the context clearly indicates otherwise. In this application, expressions such as “includes” or “having” are intended to specify the presence of features, quantities, steps, operations, components, parts, or combinations thereof described in the specification, and are understood not to preemptively exclude the presence or possibility of adding one or more other features, quantities, steps, operations, components, parts, or combinations thereof.

[0026] Unless otherwise defined, all terms used herein, including technical and scientific terms, have the same meaning as those commonly understood by those with ordinary skill in the art to which the concepts of this invention pertain. Furthermore, commonly used predefined terms may be interpreted as having a meaning consistent with their meaning in the context of the relevant art, and should not be interpreted in an overly formal sense unless explicitly defined herein.

[0027] Where a particular embodiment can be otherwise realized, a specific sequence of steps may be performed in a different order than that described. For example, two steps described consecutively may be performed substantially simultaneously, or in the reverse order of the description.

[0028] In the accompanying drawings, deformation of the illustrated shapes may be expected, for example, due to manufacturing techniques and / or tolerances. Therefore, embodiments of the present invention should not be construed as being limited to specific shapes of the regions illustrated herein, and may include, for example, changes in shape resulting from the manufacturing process. All terms used herein, "and / or," include each of the components mentioned and all combinations of one or more of them. The term "substrate" as used herein may mean the substrate itself or a laminated structure including a substrate and a predetermined layer or film formed on its surface. The term "surface of the substrate" as used herein may mean the exposed surface of the substrate itself or an outer surface such as a predetermined layer or film formed on the substrate.

[0029] (First Embodiment) Figure 1 is a perspective view of a battery pack 100 according to an exemplary embodiment.

[0030] Figure 2 is a perspective view showing some elements of a battery pack 100 according to an exemplary embodiment.

[0031] Referring to Figures 1 and 2, the battery pack 100 may include a lower case 110, a plurality of battery assemblies 120 containing battery cells, a center beam 130, a plurality of exhaust devices 140, a plurality of first embedded guides 151, a plurality of second embedded guides 153, a pack gasket 160, and an upper case 170. The battery pack 100 is the final form of a battery system to be installed in a mobility device or the like.

[0032] The pack case 101, which corresponds to the housing of the battery pack 100, may include the lower case 110 and the upper case 170.

[0033] The lower case 110 may provide internal space 119 for mounting multiple battery assemblies 120. In some embodiments, the lower case 110 may include a plate portion 110P and a side wall 110S. Two directions substantially parallel to the plate portion 110P are defined as the X and Y directions, and the direction substantially perpendicular to the plate portion 110P of the lower case 110 is defined as the Z direction. Each of the X, Y, and Z directions may be substantially perpendicular to one another. Unless otherwise stated, the definitions of directions are the same for the drawings below.

[0034] Multiple battery assemblies 120 may be arranged on a plate portion 110P of the lower case 110. The plate portion 110P can support the multiple battery assemblies 120. The plate portion 110P may include substantially parallel upper and lower surfaces. The upper surface of the plate portion 110P may face the multiple battery assemblies 120. The lower surface of the plate portion 110P is the opposite surface of the upper surface of the plate portion 110P.

[0035] The side wall 110S can horizontally enclose multiple battery assemblies 120. The side wall 110S can protect multiple battery assemblies 120 from the side. The side wall 110S may include a first side wall 111, a second side wall 112, a third side wall 113, and a fourth side wall 114. The first to fourth side walls 111, 112, 113, and 114 may be fixed to each other by methods such as friction stir welding or spot welding, and are not particularly limited.

[0036] The first side wall 111 and the second side wall 112 may be substantially perpendicular to the Y direction. The third side wall 113 and the fourth side wall 114 may each be substantially perpendicular to the X direction. In some embodiments, the first side wall 111 and the second side wall 112 may cover the sides of the plate portion 110P. In some embodiments, the third side wall 113 and the fourth side wall 114 may be positioned on the plate portion 110P.

[0037] In some embodiments, the first to fourth side walls 111, 112, 113, and 114 may be provided by an extrusion process. According to exemplary embodiments, the first to fourth side walls 111, 112, 113, and 114 may include internal voids, thereby reducing the weight of the side wall 110S. According to exemplary embodiments, the voids in the first to fourth side walls 111, 112, 113, and 114 may be either gas venting paths or coolant channels.

[0038] The technical idea of ​​the present invention will be described below with reference to embodiments in which each of the multiple battery assemblies 120 does not include a module frame. However, this is a non-limiting example and does not limit the technical idea of ​​the present invention in any sense. Based on what is described herein, ordinary articulators of the art will readily arrive at battery packs employing multiple battery assemblies including a module frame, as well as embodiments in which the battery cells are directly mounted within the pack case.

[0039] The center beam 130 can isolate the elements mounted on the lower case 110 from each other. This allows the center beam 130 to protect the multiple battery assemblies 120 while simultaneously preventing unwanted short circuits between them.

[0040] The center beam 130 may extend between the third side wall 113 and the fourth side wall 114. The center beam 130 may extend in the X direction. The center beam 130 may be in contact with the third side wall 113 and the fourth side wall 114. The center beam 130 may isolate multiple battery assemblies 120 from each other. The center beam 130 may be interposed between multiple battery assemblies 120.

[0041] The arrangement of the center beam 130 and the plurality of battery assemblies 120 disclosed in Figure 1 is a non-limiting example and does not limit the technical idea of ​​the present invention in any way. Based on what has been described herein, ordinary articulators of the art can easily arrive at battery packs including a variety of arrangements and numbers of center beams and battery assemblies.

[0042] Multiple exhaust devices 140 may be coupled to the fourth side wall 114. The fourth side wall 114 may include multiple exhaust holes connected to the multiple exhaust devices 140. The multiple exhaust holes may be configured to provide a path for exhausting gases and heat from inside the battery pack 100.

[0043] Multiple exhaust devices 140 may be configured to slow down thermal propagation by releasing hot gas from inside the battery pack 100 to the outside when at least one of the multiple battery assemblies 120 is in a thermal runway state.

[0044] Here, thermal runaway of multiple battery assemblies 120 is a state in which the temperature change of the multiple battery assemblies 120 is further accelerated, resulting in an uncontrollable positive feedback loop. Multiple battery assemblies 120 in a thermal runaway state exhibit a rapid temperature increase and may emit large amounts of high-pressure gas and combustion residue.

[0045] Multiple first embedded guides 151 may be positioned on the side wall 110S. Multiple first embedded guides 151 may be positioned on the corners 110C of the upper surface 110a (see Figure 3) of the side wall 110S. Multiple first embedded guides 151 may be coupled to the corners 110C of the upper surface 110a (see Figure 3) of the side wall 110S. Multiple first embedded guides 151 may be partially embedded in the side wall 110S. Multiple first embedded guides 151 may partially protrude from the side wall 110S.

[0046] Multiple second embedded guides 153 may be positioned on the side wall 110S. Multiple second embedded guides 153 may be positioned on the upper surface 110a (see Figure 3) of the side wall 110S. Multiple second embedded guides 153 may be interposed between the corners 110C of the side wall 110S. Multiple second embedded guides 153 may be interposed between multiple first embedded guides 151. Multiple second embedded guides 153 may be coupled to the upper surface 110a (see Figure 3) of the side wall 110S. Multiple second embedded guides 153 may be partially embedded in the side wall 110S. Multiple second embedded guides 153 may partially protrude from the side wall 110S.

[0047] Each of the multiple first embedded guides 151 and second embedded guides 153 may contain a metallic material. Each of the multiple first embedded guides 151 and second embedded guides 153 may contain, for example, aluminum. Each of the multiple first embedded guides 151 and second embedded guides 153 may also contain, for example, steel such as carbon steel, nickel steel, chromium steel, nickel-chromium steel, and manganese steel.

[0048] The battery pack 100 may further include electrical components. In some embodiments, the electrical components may be mounted on the lower case 110. In some embodiments, the electrical components may be located between the fourth side wall 114, on which the exhaust device 140 is installed, and the multiple battery assemblies 120. In some embodiments, the electrical components may include any electronic elements necessary to power the battery pack.

[0049] In some embodiments, the electrical components may include, for example, a battery management system (BMS). The BMS may be configured to perform tasks such as monitoring, balancing, and controlling the battery pack. In some embodiments, monitoring of the battery pack 100 may include measuring the voltage and current at specific nodes within a plurality of battery assemblies 120, and measuring the temperature at a set location within the battery pack 100. In some embodiments, the battery pack 100 may include measuring instruments for measuring the aforementioned voltage, current, and temperature.

[0050] The balancing of the battery pack 100 is an operation that reduces deviations between multiple battery assemblies 120. The control of the battery pack 100 includes preventing overcharging, over-discharging, and overcurrent. Through monitoring, balancing, and control, the battery pack 100 can operate under optimal conditions, thereby preventing or reducing shortening of the lifespan of each of the multiple battery assemblies 120.

[0051] The above electrical components may further include a cooling system, a power relay assembly (PRA), a safety plug, and the like. The cooling system may include a cooling fan. The cooling fan can prevent each of the multiple battery assemblies 120 from overheating by circulating air inside the battery pack 100. The PRA may be configured to supply or cut off power from the high-voltage battery to an external load (e.g., the vehicle's motor). The PRA can protect the multiple battery assemblies 120 and the external load (e.g., the vehicle's motor) by cutting off the power supply to the external load (e.g., the vehicle's motor) in situations where abnormal voltages occur, such as a voltage surge.

[0052] The battery pack 100 may further include a plurality of busbars configured to electrically connect a plurality of battery assemblies 120. The plurality of battery assemblies 120 may be connected in series and / or parallel by the plurality of busbars. This may configure the battery pack 100 to output a high voltage to an external load (e.g., a vehicle motor).

[0053] The pack gasket 160 may contain a material that is elastic in response to applied pressure. The pack gasket 160 may contain rubber synthesized from a material such as EPDM (ethylene-propylene diene monomer). When the lower case 110 and the upper case 170 are joined, the pack gasket 160 may be interposed between the lower case 110 and the upper case 170. The lower case 110 and the upper case 170 may pressurize the pack gasket 160 so that it deforms slightly. This allows the battery pack 100 to be sealed and external fluids to be isolated from the internal space of the battery pack 100.

[0054] The upper case 170 may be coupled to the lower case 110. In some embodiments, the upper case 170 may include a main surface and an edge. The main surface may cover elements mounted on the battery pack 100, such as a plurality of battery assemblies 120 and electrical components. The edge is the surface in contact with the lower case 110. In some embodiments, the upper case 170 may be flat, in which case the edge may horizontally surround the main surface. In some embodiments, the main surface may be elevated compared to the edge, and the edge and the main surface may be connected by a curved portion.

[0055] The upper case 170 may be coupled to the side wall 110S of the lower case 110 by a plurality of first embedding guides 151 and second embedding guides 153. According to an exemplary embodiment, the battery pack 100 may further include elements coupled to the plurality of first embedding guides 151 and second embedding guides 153 for securing the upper case 170 to the side wall 110S of the lower case 110. These elements may include, but are not limited to, bolts and nuts.

[0056] Figure 3 is a partial cross-sectional perspective view showing a cross-section of the battery pack 100 from Figure 1, cut along the line III-III' in Figure 2.

[0057] Referring to Figure 3, the first side wall 111 may include a hollow channel H. The first side wall 111 including the hollow channel H can have its weight reduced by a proportion corresponding to the volume of the hollow channel H. Furthermore, the hollow channel H may be used as a venting channel for gases generated within the battery pack 100, or as a channel for a cooling medium.

[0058] The upper case 170 covers the lower case 110 and is coupled to the upper surface 110a of the lower case. In some embodiments, the edge of the upper case 170 is coupled to the upper surface 110a of the lower case. In some embodiments, the upper case 170 may be configured as a flat plate. Alternatively, as shown in Figure 3, the edge of the upper case 170 may be formed by a flange portion 172, and the inner portion of the edge of the upper case 170 may be composed of a cover portion 171 that is bent upward from the flange portion 172. In this case, the height of the cover portion 171 is formed to be greater than the height of the flange portion 172. By configuring the upper case 170 with a flange portion 172 and a cover portion 171 in this way, the bending rigidity becomes even stronger than that of a flat plate upper case 170, and the upper case 170 as a whole may become more rigid. In addition, the gap between the upper case 170 and the battery assembly 120 becomes larger, which may make it easier to vent the gas generated in the battery pack 100 through this gap.

[0059] A pack gasket 160 is interposed between the upper case 170 and the lower case 110.

[0060] The pack gasket 160 may have a shape corresponding to the shape of the side wall 110S of the lower case 110 and may be provided along the upper surface 110a of the lower case. In some embodiments, the pack gasket 160 may include a plurality of through fastening holes 160a formed at predetermined intervals.

[0061] The above-mentioned pack gasket 160 includes a gasket body 162 and a heat-resistant plastic member 164.

[0062] Figure 4 is a cross-sectional perspective view showing the main part of a pack gasket 160 according to one embodiment of the present invention.

[0063] Referring to Figures 3 and 4, the pack gasket 160 includes a first surface 160t facing the upper case 170 and a second surface 160b facing the lower case 110. The first surface 160t and the second surface 160b may be opposite surfaces. The pack gasket 160 also includes a first side portion 160sa facing the internal space 119 (see Figure 2) and a second side portion 160sb facing the outside of the pack case 101. The first side portion 160sa and the second side portion 160sb are located on opposite sides.

[0064] In some embodiments, the pack gasket 160 includes a heat-resistant plastic member 164 between the first side portion 160sa and the second side portion 160sb in any cross-section in the width direction. In any cross-section, the entire cross-section may be made of the heat-resistant plastic member 164, or only a portion of the cross-section may be made of the heat-resistant plastic member 164.

[0065] In some embodiments, the material of the heat-resistant plastic member 164 may be selected such that it does not deform at high temperatures, or only slightly, and does not undergo morphological changes due to melting or carbonization. Specifically, the material of the heat-resistant plastic member 164 may be selected such that it does not undergo morphological changes due to melting or carbonization at temperatures of 600°C or higher, 700°C or higher, 800°C or higher, or 800°C to 1,000°C for a predetermined time.

[0066] The heat-resistant plastic member 164 may include one or more of the following: acrylonitrile resins, acrylic resins, benzimidazole resins, indoline resins, imide resins, amide resins, phenylene oxide resins, butylene terephthalate resins, fluororesins, or copolymers thereof. More specifically, the heat-resistant plastic member 164 may be one or more selected from the group consisting of, for example, modified polyphenylene oxide (MPPO), modified polysulfone (MPSU), polycarbonate (PC), polyamide, polysulfone (PSU), polyethersulfone (PES), polyetherimide (PEI), polyphenylene sulfide, liquid crystal polymer, polyetheretherketone (PEEK), and mixtures thereof, but the present invention is not limited thereto.

[0067] In some embodiments, the heat-resistant plastic member 164 may include a phenylene oxide resin such as polyphenylene oxide (PPO), an amide resin such as nylon, a mixture thereof, or a copolymer thereof. In some embodiments, the phenylene oxide resin and the amide resin may be applied in a form in which some repeating units are modified.

[0068] In some embodiments, the heat-resistant plastic member 164 may further include an inorganic filler and / or a fibrous structure.

[0069] The inorganic fillers mentioned above may include, but are not limited to, silica, alumina, potassium titanate, urastonite, xonotlite, dawsonite, acicular MgO, acicular magnesium hydroxide, and aluminum borate.

[0070] The above-mentioned fibrous structures may be, but are not limited to, glass fibers, carbon fibers, slag fibers, phosphate fibers, gypsum fibers, aramid fibers, etc.

[0071] The gasket body portion 162 described above may include rubber synthesized from a substance such as EPDM (ethylene-propylene diene monomer).

[0072] Even if a flame is generated inside the battery pack 100 and reaches the inside of the upper case 170 and lower case 110, the heat-resistant plastic member 164 can protect at least a portion of the gasket body 162. In other words, the heat-resistant plastic member 164 can maintain the sealing performance of the pack gasket 160 by protecting at least a portion of the gasket body 162.

[0073] In some embodiments, the gasket body portion 162 may include a first portion P1 interposed between the upper case 170 and the lower case 110, and a second portion P2 extending from the first portion P1 toward the internal space 119 (see Figure 2).

[0074] The first portion P1 described above may extend between the upper case 170 and the lower case 110 along the joint surface between the upper case 170 and the lower case 110, for example, along the upper surface 110a of the lower case. The width of the first portion P1 does not have to be the same as the width of the upper surface 110a of the lower case, but may be about 50% or more, about 55% or more, about 60% or more, about 65% or more, about 70% or more, about 75% or more, about 80% or more, about 85% or more, about 90% or more, or about 95% or more of the width of the upper surface 110a of the lower case.

[0075] The second portion P2 is integral with the first portion P1 and is not interposed between the upper case 170 and the lower case 110. The second portion P2 may extend along the side of the first portion P1 along the side wall of the upper case 170 and / or the side wall of the lower case 110. Figure 3 illustrates an example in which the second portion P2 extends along the side wall of the lower case 110, but the present invention is not limited thereto.

[0076] The gasket body portion 162 includes a housing portion 162R, and the heat-resistant plastic member 164 can be housed within the housing portion 162R. In some embodiments, the heat-resistant plastic member 164 can be inserted into the housing portion 162R. In some embodiments, the heat-resistant plastic member 164 can be integrated with the gasket body portion 162 by an insert mold method.

[0077] In some embodiments, the heat-resistant plastic member 164 may be formed integrally with the gasket body portion 162. In some embodiments, the heat-resistant plastic member 164 may be integrated with the gasket body portion 162. Here, the integration of the heat-resistant plastic member 164 with the gasket body portion 162 means that the heat-resistant plastic member 164 and the gasket body portion 162 were formed separately and then integrated by a subsequent process.

[0078] The heat-resistant plastic member 164 may be positioned closer to the internal space 119 than the center CL of the first side portion 160sa and the second side portion 160sb. Because the heat-resistant plastic member 164 is positioned closer to the internal space 119 than the center CL, most of the gasket body portion 162 is positioned further away from the internal space 119 than the heat-resistant plastic member 164. Even if flames are generated and reach the inside of the upper case 170 and the lower case 110, most of the gasket body portion 162 is protected by the heat-resistant plastic member 164, so that the sealing performance of the pack gasket 160 can be maintained well.

[0079] In some embodiments, the dimensions of the heat-resistant plastic member 164 in the thickness direction (perpendicular direction in Figure 4) of the first portion P1 may be the same as or greater than the thickness of the first portion P1. Since the first portion P1 is interposed between the upper case 170 and the lower case 110, it can be said that sealing performance is ensured by the first portion P1. If the dimensions of the heat-resistant plastic member 164 in the thickness direction (perpendicular direction in Figure 4) of the first portion P1 are even greater than the thickness of the first portion P1, then the first portion P1 can be protected from flames at least over its entire thickness. Therefore, the sealing performance of the pack gasket 160 can be well maintained.

[0080] In some embodiments, when the upper case 170 and the lower case 110 are joined, they are separated from each other by at least the thickness of the first portion P1. At this time, the heat-resistant plastic member 164 can be extended at least over the separation distance in the thickness direction of the first portion P1 (the vertical direction in Figure 4). If the dimensions of the heat-resistant plastic member 164 in the thickness direction of the first portion P1 (the vertical direction in Figure 4) are greater than the separation distance, the first portion P1 interposed between the upper case 170 and the lower case 110 can be protected from flames. Thus, the sealing performance of the pack gasket 160 can be well maintained.

[0081] In some embodiments, the heat-resistant plastic member 164 may not be interposed between the upper case 170 and the lower case 110. In this case, the storage portion 162R may be provided in the second portion P2.

[0082] In some embodiments, the heat-resistant plastic member 164 may be positioned to overlap the first portion P1 in the lateral direction over the entire thickness of the first portion P1. Because it overlaps the first portion P1 over its entire thickness, the first portion P1 can be protected from flames over its entire thickness. Therefore, the sealing performance of the pack gasket 160 can be well maintained.

[0083] (Additional implementation) Figure 5 is a partial cross-sectional perspective view showing a cross-section of a battery pack 100 according to another embodiment of the present invention, obtained by cutting along the line III-III' in Figure 2. The embodiment shown in Figure 5 is substantially the same as the embodiment shown in Figure 3, except that the cross-sectional shape of the heat-resistant plastic member 164 is different. Therefore, the following description will focus on the differences between the two embodiments, and redundant explanations will be omitted.

[0084] Referring to Figure 5, the heat-resistant plastic member 164 is partially interposed between the upper case 170 and the lower case 110. In this case, the cross-section of the heat-resistant plastic member 164 may have an inverted L-shape. Furthermore, a portion of the heat-resistant plastic member 164 may protrude from between the upper case 170 and the lower case 110 toward the internal space 119 (see Figure 2).

[0085] Since the heat-resistant plastic member 164 of this embodiment is partially interposed between the upper case 170 and the lower case 110, it may be possible to more reliably protect the first portion P1 of the gasket body 162 from flames. Therefore, the sealing performance of the pack gasket 160 can be maintained more effectively.

[0086] Figure 6 is a partial cross-sectional perspective view showing a cross-section of a battery pack 100 according to another embodiment of the present invention, obtained by cutting along the line III-III' in Figure 2. The embodiment shown in Figure 6 is substantially the same as the embodiment shown in Figure 5, except that the cross-sectional shape of the heat-resistant plastic member 164 is different. Therefore, the following description will focus on the differences between the two embodiments, and redundant explanations will be omitted.

[0087] Referring to Figure 6, the dimensions of the heat-resistant plastic member 164 in the thickness direction of the first portion P1 are smaller than the thickness of the first portion P1. However, the heat-resistant plastic member 164 is partially interposed between the upper case 170 and the lower case 110. Furthermore, a portion of the heat-resistant plastic member 164 may have a form that protrudes from between the upper case 170 and the lower case 110 toward the internal space 119 (see Figure 2).

[0088] Since the dimension of the heat-resistant plastic member 164 in the thickness direction is reduced, it can be said that the performance of protecting the first part P1 from flames is somewhat reduced. However, since the heat-resistant plastic member 164 is partially interposed between the upper case 170 and the lower case 110, the overall performance of protecting the first part P1 from flames may not be impaired.

[0089] Furthermore, because the heat-resistant plastic member 164 is somewhat wider and inserted to a shallower depth, the pack gasket 160 according to this embodiment is easy to manufacture and may be advantageous for mass production.

[0090] Figure 7 is a partial cross-sectional perspective view showing a cross-section of a battery pack 100 according to another embodiment of the present invention, cut along the line III-III' in Figure 2. The embodiment shown in Figure 7 differs from the embodiments shown in Figures 3, 5, and 6 in that the entire heat-resistant plastic member 164 is interposed between the upper case 170 and the lower case 110. Below, the differences from the other embodiments will be explained in detail, and redundant explanations will be omitted.

[0091] Referring to Figure 7, the entire pack gasket 160 is interposed between the upper case 170 and the lower case 110. That is, not only the gasket body portion 162, but also the entire heat-resistant plastic member 164 is interposed between the upper case 170 and the lower case 110. The heat-resistant plastic member 164 may extend along the side surface of the gasket body portion 162. The heat-resistant plastic member 164 is located on the internal space side of the gasket body portion 162.

[0092] The gasket body 162 and the heat-resistant plastic member 164 can be joined in any manner. For example, the gasket body 162 and the heat-resistant plastic member 164 can be joined to each other by an insert mold. However, the present invention is not limited thereto.

[0093] Figure 8 is a partial cross-sectional perspective view showing a cross-section of a battery pack 100 according to another embodiment of the present invention, obtained by cutting along the line III-III' in Figure 2.

[0094] Referring to Figure 8, a protruding projection P is provided on the upper surface 110a of the lower case. Even if a flame is generated inside the battery pack 100 and reaches the inside of the upper case 170 and the lower case 110, the protruding projection P blocks the pack gasket 160, so the flame cannot reach the pack gasket 160. Furthermore, even if thermal energy from the flame is transferred to the pack gasket 160 by passing through the protruding projection P, the heat-resistant plastic member 164 protects the gasket body 162, so the gasket body 162 can maintain its sealing performance.

[0095] The protruding projection P may be located on the upper surface 110a of the lower case along the side surface of the pack gasket 160. In some embodiments, the protruding projection P may be formed integrally with the lower case 110. In some embodiments, the protruding projection P may be manufactured separately and then integrated with the upper surface 110a of the lower case by welding or other means.

[0096] Figure 9 is a partial perspective view of the battery pack 100 of this embodiment.

[0097] The top view of Figure 9 shows the state in which the pack gasket 160 is not installed on the lower case 110, while the bottom view of Figure 9 shows the state in which the pack gasket 160 is installed on the lower case 110.

[0098] As described above, the first to fourth side walls 111, 112, 113, and 114 can be fixed to each other by methods such as friction stir welding and spot welding. For example, the first side wall 111 and the fourth side wall 114 can be positioned perpendicular to each other, and their respective ends can be joined by welding. As a result, welded joints W1 and W2 are formed at the corner where the first side wall 111 and the fourth side wall 114 are joined. Specifically, welded joints W1 and W2 are formed on the upper surface and the side edge of the corner.

[0099] Due to the characteristics of welding, the welded portion W1 may protrude slightly from the upper surface 110a of the lower case. Such protrusion can prevent the pack gasket 160 from adhering tightly to the upper surface 110a of the lower case, so flattening is required. However, if the protruding projection P extends to the corner portion, it becomes extremely difficult to flatten the protrusion of the welded portion W1, reducing production efficiency.

[0100] In the battery pack 100 of this embodiment, in view of these points, it is possible that the protruding projection P may not be provided over a predetermined length range A near the corner portion. In this case, the pack gasket 160 at the corner portion may be vulnerable to flames. To prepare for such a case, it is necessary to reinforce the pack gasket 160 at the corner portion. Figure 10 is a partial perspective view of the lower case 110 with a pack gasket 160 with a reinforced corner portion attached.

[0101] Referring to Figure 10, the protruding projection P is omitted at the corner portion, and the pack gasket 160 can be extended toward the internal space in the portion where the protruding projection P is omitted. A heat-resistant plastic member 164 can be provided in the portion of the pack gasket 160 that is extended toward the internal space.

[0102] In some embodiments, the gasket body portion 162 belonging to the second portion P2 may extend horizontally from the gasket body portion 162 belonging to the first portion P1 toward the internal space. Furthermore, the gasket body portion 162 belonging to the second portion P2 may extend vertically along the first side wall 111 and the fourth side wall 114. A storage compartment is formed in the second portion P2 of the gasket body portion 162, and a heat-resistant plastic member 164 may be provided within the storage compartment.

[0103] A typical engineer would not consider the configuration of the pack gasket 160 at the corner to be limited to that shown in Figure 10, but rather that various embodiments described with reference to Figures 5 to 7 can be applied with suitable modifications. Furthermore, although Figure 10 describes the corner where the first side wall 111 and the fourth side wall 114 meet, a typical engineer would consider that the same can be applied to other corners.

[0104] In Figure 10, the side surface of the heat-resistant plastic member 164 is not exposed and is shown to be surrounded by the gasket body portion 162, but the present invention is not limited thereto. In some embodiments, the side wall of the second portion P2, which extends vertically along the first side wall 111 and the fourth side wall 114, may include a hole that exposes the heat-resistant plastic member 164.

[0105] In the embodiment of the battery pack 100 described with reference to Figures 9 and 10, the pack gasket 160, and in particular the first portion P1 of the gasket body 162, can be protected by protruding projections P in the portions where the first to fourth side walls 111, 112, 113, and 114 extend horizontally. Furthermore, in the battery pack 100, the first portion P1 can be protected by a heat-resistant plastic member 164 provided on the gasket body 162 in the corner portions where the first to fourth side walls 111, 112, 113, and 114 meet each other. As a result, the entire first portion P1 interposed between the upper case 170 and the lower case 110 is protected, and the sealing performance of the pack gasket 160 can be maintained even when exposed to high temperatures and / or flames.

[0106] As described above, embodiments of the present invention have been described in detail, but a person with ordinary skill in the art to which the present invention pertains can modify and implement the present invention in various ways without departing from the spirit and scope of the invention as defined in the appended claims. Therefore, future modifications of embodiments of the present invention will not depart from the art of the present invention. [Explanation of Symbols]

[0107] 100 Battery Packs 101 Pack Case 110 Lower case 110C Corner 110P Plate Section 110S side wall 111 First side wall 112 Second side wall 113 Third side wall 114 Fourth side wall 119 Interior space 120 Battery Assembly 130 Center Beam 140 Exhaust system 151 First embedded guide 153 Second embedded guide 160 Pack Gaskets 160 Gasket 160a Through-hole fastening 160b 2nd surface 160sa First side 160sb Second side 160t 1st surface 162 Gasket body 162R Storage compartment 164 Heat-resistant plastic components 170 Top Case 171 Cover section 172 Flange section CL center H Hollow Channel MgO needle-shaped P protrusion P1 Part 1 P2 2nd part W1 Weld W2 weld

Claims

1. A pack case including a lower case and an upper case that define the internal space, Multiple battery cells provided within the aforementioned internal space, Includes a pack gasket provided between the lower case and the upper case, The aforementioned pack gasket is The first surface facing the upper case, A second surface opposite to the first surface, which faces the lower case, The first side facing the internal space, The pack case includes a second side portion facing the outside, The pack gasket includes, in any cross-section in the width direction, at least partially, a heat-resistant plastic member between the first side and the second side. The pack gasket includes a gasket body and a heat-resistant plastic member positioned to protect at least a portion of the gasket body. The gasket body portion includes a storage portion, The heat-resistant plastic member is placed inside the storage compartment. The gasket body portion is, A first portion interposed between the upper case and the lower case, A second portion extends from the first portion into the internal space and along the side walls of the upper case and / or the lower case, Includes, A battery pack in which the second portion is not interposed between the upper case and the lower case, the storage portion is formed in the second portion, and the heat-resistant plastic member is not interposed between the upper case and the lower case.

2. The heat-resistant plastic member extends at least partially along the joint surface between the upper case and the lower case, The battery pack according to claim 1, wherein the heat-resistant plastic member is positioned closer to the internal space than the center between the first side and the second side.

3. The battery pack according to claim 1, wherein in the thickness direction of the first portion, the dimensions of the heat-resistant plastic member are even greater than the thickness of the first portion.

4. The battery pack according to claim 1, wherein the heat-resistant plastic member is arranged to overlap the first portion with the first portion in the lateral direction over the entire thickness of the first portion.

5. The battery pack according to claim 1, wherein the heat-resistant plastic member is formed integrally with or integrated with the gasket body.

6. The battery pack according to claim 5, wherein the heat-resistant plastic member is integrated with the gasket body using an insert mold method.

7. The battery pack according to claim 5, wherein the heat-resistant plastic member comprises one or more of the following: acrylonitrile resin, acrylic resin, benzimidazole resin, indoline resin, imide resin, amide resin, phenylene oxide resin, butylene terephthalate resin, fluororesin, or copolymers thereof.

8. A pack case including a lower case and an upper case that define the internal space, Multiple battery cells provided within the aforementioned internal space, Includes a pack gasket provided between the lower case and the upper case, The pack gasket includes a heat-resistant plastic member that extends along the joint surface between the upper case and the lower case, and a gasket body portion. The heat-resistant plastic member is integrated with the gasket body, The pack gasket includes a gasket body and a heat-resistant plastic member positioned to protect at least a portion of the gasket body. The gasket body portion includes a storage portion, The heat-resistant plastic member is placed inside the storage compartment. The gasket body portion is, A first portion interposed between the upper case and the lower case, A second portion extends from the first portion into the internal space and along the side walls of the upper case and / or the lower case, Includes, A battery pack in which the second portion is not interposed between the upper case and the lower case, the storage portion is formed in the second portion, and the heat-resistant plastic member is not interposed between the upper case and the lower case.

9. The gasket body includes a storage section, The heat-resistant plastic member is inserted into the storage compartment, as described in claim 8.

10. The battery pack according to claim 8, wherein the heat-resistant plastic member extends at least over the distance between the upper case and the lower case.

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