Battery pack

Abstract

The battery pack of the present invention includes a lower pack housing having a bottom plate and a side wall frame surrounding an edge of the bottom plate, an upper lid covering the lower pack housing and coupled to an upper surface of the side wall frame, and a pack gasket installed between the upper surface of the side wall frame and the upper lid, and is characterized in that a first protrusion is provided along the upper surface of the side wall frame to isolate the inside of the battery pack from the pack gasket.

Description

[Technical field]

[0001] The present invention relates to a battery pack, and more particularly to a battery pack capable of effectively protecting a pack gasket installed between an upper lid and a side wall frame of the battery pack.

[0002] This application claims the benefit of priority based on Korean Patent Application No. 10-2022-0144331 dated November 2, 2022, and all contents disclosed in the documents of that Korean patent application are incorporated herein by reference. [Background technology]

[0003] A battery pack applied to an electric vehicle or the like contains a number of battery modules including a number of secondary batteries to obtain high output, and the battery modules are connected in series or parallel. The secondary battery can be repeatedly charged and discharged by electrochemical reactions between components including positive and negative electrode current collectors, separators, active materials, electrolytes, etc.

[0004] In addition, a pack gasket is installed between an upper lid covering an upper portion of the battery pack and an upper surface of a lower pack housing accommodating the battery module for sealing.

[0005] FIG. 1 is an exploded perspective view of a conventional battery pack, and FIG. 2 is a schematic diagram showing a state in which a flame occurs inside the conventional battery pack.

[0006] As shown in the figure, a conventional battery pack 1 includes a lower pack housing 10 in which a battery module M is accommodated, and an upper lid 20 that is coupled to cover the lower pack housing 10. The lower pack housing 10 includes a bottom plate 11 and a side wall frame 12 that surrounds an edge of the bottom plate. The bottom plate 11 may be provided with left and right partition walls 13 and a central partition wall 14 for separating and accommodating the battery modules.

[0007] A pack gasket 30 is installed on the upper surface of the side wall frame 12 for sealing. The pack gasket 30 has a plurality of fastening holes 30a. The upper lid 20 also has a plurality of fastening holes corresponding to the fastening holes 30a at its edge. Thus, the upper lid 20 and the pack gasket 30 are coupled to the side wall frame 12 by coupling fastening members to the corresponding fastening holes of the upper lid 20 and the pack gasket 30.

[0008] FIG. 2 shows how the top lid 20 is coupled onto the side wall frame 12 via the pack gasket 30. However, thermal runaway may occur in a battery module or battery cell housed inside the battery pack, causing high-temperature gas and flames inside the battery pack. Arrow F in FIG. 2 indicates the direction of propagation of gas and flames generated inside the battery pack. As shown in the figure, the high-temperature gas and flames move upward and come into contact with the inner surface of the top lid 20, the side of the pack gasket 30, and the inner surface of the side wall frame 12. The top lid 20 and the side wall frame 12 are made of metal materials such as steel and aluminum, and therefore can withstand high-temperature gas and flames up to a set heat-resistant temperature. However, the pack gasket 30 is usually made of a soft rubber (e.g., EPDM: ethylene propylene diene monomer) material for sealing, and such a rubber pack gasket easily melts when exposed to flames. Alternatively, the pack gasket may be pushed out by the pressure inside the pack due to thermal runaway, causing a leak. If this happens, the sealing of the battery pack may be destroyed, causing a leak and allowing high-temperature gases and flames to be discharged outside the battery pack, which may cause secondary damage.

[0009] Therefore, there is a need to develop technology that can protect the pack gasket in the event of a fire or other event inside the battery pack. [Prior art documents] [Patent documents]

[0010] [Patent Document 1] Korean Patent Publication No. 2022-0100465 Summary of the Invention [Problem to be solved by the invention]

[0011] The present invention has been devised to solve the above problems, and an object of the present invention is to provide a battery pack capable of protecting a pack gasket by installing an insulating structure on an upper surface of a side wall frame. [Means for solving the problem]

[0012] To solve the above problems, one embodiment of the present invention provides a battery pack comprising a lower pack housing having a bottom plate and a side wall frame surrounding an edge of the bottom plate, an upper lid covering the lower pack housing and coupled to an upper surface of the side wall frame, and a pack gasket installed between the upper surface of the side wall frame and the upper lid, wherein a first protrusion is provided along the upper surface of the side wall frame to isolate the inside of the battery pack from the pack gasket.

[0013] A gap of a predetermined width may be provided between the first protrusion and the pack gasket.

[0014] The height of the first protrusion is lower than the height of the pack gasket, and an upper surface of the pack gasket may be compressed by a bonding force of an upper lid that is bonded to the side wall frame, so that the upper surface of the pack gasket may be positioned at the same height as the upper surface of the first protrusion.

[0015] A second protrusion may be provided along an upper surface of the sidewall frame covering a side of the pack gasket opposite the side of the pack gasket blocked by the first protrusion, and the pack gasket may be mounted on the upper surface of the sidewall frame between the first and second protrusions.

[0016] A gap of a predetermined width may be provided between at least one of the first projection and the pack gasket and the second projection and the pack gasket.

[0017] The first and second protrusions have the same height, which is lower than the height of the pack gasket, and the upper surface of the pack gasket is compressed by the bonding force of the upper lid which is bonded to the side wall frame, so that the upper surface of the pack gasket is positioned at the same height as the upper surfaces of the first and second protrusions.

[0018] The top lid and pack gasket each have corresponding through fastening holes, and fastening members can be passed through the through fastening holes and coupled to the sidewall frame, thereby coupling the top lid and pack gasket to an upper surface of the sidewall frame.

[0019] The side wall frame is assembled by welding vertically arranged side wall frame parts, and the first protrusion may not be provided on an upper surface of the side wall frame over a predetermined length range centered on a corner portion of the side wall frame to which the side wall frame part is welded.

[0020] In addition, the side wall frame is assembled by welding vertically arranged side wall frame parts, and the first and second protrusions may not be provided on the upper surface of the side wall frame over a predetermined length range centered on the corner portion of the side wall frame to which the side wall frame parts are welded.

[0021] A fire protection bracket may be coupled to a corner of the upper lid corresponding to the corner of the side wall frame, for isolating the corner of the side wall frame from the inside of the battery pack.

[0022] The flame breaker bracket may extend laterally from the corner portion of the upper lid along the inner surface of the corner portion of the side wall frame for a length equal to or greater than the predetermined length, and may extend downwardly along the inner surface of the corner portion of the side wall frame to cover the corner portion of the side wall frame.

[0023] The upper lid may be coupled to the side wall frame such that the fire protection bracket is in intimate contact with an inner surface of a corner of the side wall frame or is spaced apart from the inner surface by a predetermined distance.

[0024] The upper lid may include a flange portion coupled to an upper surface of the side wall frame and a cover portion bent upward from the flange portion, and the fire protection bracket may be installed at a corner of the cover portion.

[0025] The fire protection bracket may include an upper plate bracket coupled to the cover portion, and a corner bracket extending downward from the upper plate bracket and extending along an inner surface of a corner portion of the side wall frame. Effect of the Invention

[0026] According to the present invention, the upper surface of the side wall frame is provided with a first protrusion that isolates the pack gasket from the inside of the battery pack, so that the pack gasket can be stably protected even when high-temperature gas or flame occurs, thereby maintaining or improving the sealing performance of the battery pack.

[0027] Furthermore, according to one embodiment of the present invention, the pack gasket can be protected more completely by providing protrusions that completely cover both sides of the pack gasket.

[0028] Furthermore, according to one embodiment of the present invention, a gap of a predetermined width is provided between the pack gasket and the protrusion, and the pack gasket is spaced from the side wall frame, thereby preventing the pack gasket from melting due to heat transferred from the side wall frame.

[0029] In addition, according to one embodiment of the present invention, the above-mentioned protrusion is not formed at the corner portion of the side wall frame, so that the side wall frame part weld portion protrudingly formed at the corner portion can be easily flattened.

[0030] Furthermore, even if no protrusions are formed at the corners of the side wall frames, a flame blocking bracket can be installed to isolate the corners of the side wall frames from the inside of the battery pack, thereby preventing the pack gasket at the pack corners from being directly exposed to flames. [Brief description of the drawings]

[0031] [Figure 1] FIG. 1 is an exploded perspective view of a conventional battery pack. [Diagram 2] 1 is a schematic diagram showing a state in which a flame occurs inside a conventional battery pack. [Diagram 3] FIG. 1 is an exploded perspective view of a battery pack according to a first embodiment of the present invention. [Figure 4] FIG. 2 is a partially cutaway perspective view of the battery pack of the first embodiment. [Diagram 5] FIG. 2 is a side cross-sectional view of the battery pack of the first embodiment. [Figure 6] FIG. 11 is an exploded perspective view of a battery pack according to a second embodiment of the present invention. [Figure 7] FIG. 11 is a side cross-sectional view of a battery pack according to a second embodiment. [Figure 8] FIG. 11 is a partial perspective view of a battery pack according to a third embodiment of the present invention. [Figure 9] FIG. 11 is a perspective view of a battery pack according to a fourth embodiment of the present invention. [Figure 10] FIG. 13 is a perspective view showing a main part of a battery pack according to a fourth embodiment. [Figure 11] FIG. 13 is a partial perspective view of a battery pack according to a fourth embodiment. [Figure 12] FIG. 13 is a partially cutaway perspective view of a battery pack according to a fourth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0032] The present invention will be described in detail below. Before that, the terms and words used in the specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings, but should be interpreted as meanings and concepts that are consistent with the technical idea of ​​the present invention based on the principle that an inventor can appropriately define the concept of a term to best describe his own invention.

[0033] In this application, the terms "comprise" and "have" are intended to specify the presence of a feature, number, step, operation, component, part, or combination thereof described in the specification, and may be understood as not precluding the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof. In addition, when a part such as a layer, film, region, or plate is described as being "on" another part, this includes not only the case where it is "directly on" the other part, but also the case where there is another part in between. Conversely, when a part such as a layer, film, region, or plate is described as being "under" another part, this includes not only the case where it is "directly under" the other part, but also the case where there is another part in between. In addition, in this application, being "on" may include not only the case where it is located on the top, but also the case where it is located on the bottom.

[0034] A battery pack according to one embodiment of the present invention includes a lower pack housing having a bottom plate and a side wall frame surrounding an edge of the bottom plate, an upper lid covering the lower pack housing and coupled to an upper surface of the side wall frame, and a pack gasket installed between the upper surface of the side wall frame and the upper lid, and is characterized in that a first protrusion is provided along the upper surface of the side wall frame to isolate the inside of the battery pack from the pack gasket.

[0035] Hereinafter, specific embodiments of the present invention will be described with reference to the drawings.

[0036] (First embodiment) FIG. 3 is an exploded perspective view of a battery pack according to a first embodiment of the present invention, FIG. 4 is a partially cutaway perspective view of the battery pack according to the first embodiment, and FIG. 5 is a side cross-sectional view of the battery pack according to the first embodiment.

[0037] The battery pack 100 of the first embodiment includes a lower pack housing 110 having a bottom plate 111 and a sidewall frame 112 surrounding the edges of the bottom plate 111, an upper lid 120 covering the lower pack housing 110 and coupled to an upper surface 112a of the sidewall frame, and a pack gasket 130 installed between the upper surface 112a of the sidewall frame and the upper lid 120.

[0038] The lower pack housing 110 accommodates a plurality of battery modules M. The lower pack housing 110 includes a bottom plate 111 on which the battery modules M are seated. A cooling channel may be incorporated in the bottom plate 111, or a separate cooling panel (not shown) incorporating a cooling channel may be attached. A thermally conductive resin layer (not shown) may be applied to the bottom plate 111. A partition may be provided on the bottom plate 111 to accommodate the battery modules M in a divided manner. In the illustrated example, left and right partitions 113 and a central partition 114 are provided on the bottom plate 111. However, the battery pack structure of the present invention may also be applied to a battery pack not including a partition. In addition, the shape of the partition is not limited to the shape shown in FIG. 3, and of course, other shapes of partitions may also be applied.

[0039] The lower pack housing 110 includes a sidewall frame 112 that surrounds the edge of the bottom plate. The sidewall frame 112 can be assembled by connecting four panels (sidewall frame parts) to each other on the front, back, left and right sides. Adjacent sidewall frame parts are arranged perpendicular to each other, and ends of each vertically arranged part are connected to each other. The ends of each part can be connected by fastening members or by welding contact surfaces of each end to each other.

[0040] The side wall frame part may be manufactured by an extrusion process. According to the extrusion process, a hollow channel H as shown in FIG. 4 may be formed in the side wall frame part according to the extrusion direction. Therefore, the weight of the side wall frame part may be reduced by the volume corresponding to the hollow channel H, so that the weight of the side wall frame 112 may be reduced. In addition, the hollow channel H may be used as a venting flow path for gas generated in the battery pack 100 or as a coolant flow path.

[0041] The upper lid 120 covers the lower pack housing 110 and is coupled to the upper surface 112a of the side wall frame. That is, the upper lid 120 is a portion that covers the open upper surface of the lower pack housing 110. The edge of the upper lid 120 is coupled to the upper surface 112a of the side wall frame. The upper lid 120 may be configured in a flat plate shape. Alternatively, as shown in FIG. 4, the edge of the upper lid 120 may be formed as a flange portion 122, and the inner portion of the edge of the upper lid 120 may be configured as a cover portion 121 that is bent upward from the flange portion 122. In this case, the height of the cover portion 121 is formed higher than the height of the flange portion 122. When the upper lid 120 is configured with the flange portion 122 and the cover portion 121, the bending rigidity is stronger than that of the flat upper lid 120, and the upper lid 120 becomes more sturdy overall. In addition, since the gap between the upper lid 120 and the battery module M becomes larger, this gap makes it easier to vent gas generated within the battery pack 100.

[0042] A pack gasket 130 is installed between the upper surface 112 a of the side wall frame and the upper lid 120 .

[0043] The pack gasket 130 is formed in a rectangular shape corresponding to the shape of the side wall frame 112 and is installed along the upper surface 112a of the side wall frame. A plurality of through fastening holes 130a are provided at predetermined intervals in the pack gasket 130. The pack gasket 130 is generally made of a soft rubber (e.g., EPDM: ethylene propylene diene monomer) material for sealing.

[0044] 2, when high-temperature gas or flame F occurs inside the battery pack 100, the upper lid 120 and the side wall frame 112 are made of metal materials such as steel or aluminum, and therefore can withstand up to a set heat-resistant temperature even when in contact with the high-temperature gas and flame F. However, the pack gasket 130 made of rubber may be exposed to the flame F and melt.

[0045] In the present invention, in order to protect the pack gasket 130, a first protrusion P1 is provided on the upper surface 112a of the side wall frame to isolate the pack gasket 130 from the inside of the battery pack 100. That is, as shown in Fig. 4, even if a flame F occurs inside the battery pack 100 and reaches the inner surfaces of the upper lid 120 and the side wall frame 112, the first protrusion P1 isolates the pack gasket 130, so that the flame F cannot reach the pack gasket 130. In this way, in the present invention, the first protrusion P1 is located on the side of the pack gasket 130 facing the inside of the battery pack 100 to protect the pack gasket 130 from the flame F, so that the sealing performance of the pack gasket 130 can be maintained.

[0046] The first protrusion P1 is provided on the upper surface 112a of the side wall frame along a side surface of the pack gasket 130. The first protrusion P1 may be rectangular in shape to correspond to the shape of the pack gasket 130.

[0047] Meanwhile, the first protrusion P1 may be molded integrally with the side wall frame 112. Alternatively, the first protrusion P1 may be manufactured separately and coupled to the upper surface 112a of the side wall frame by welding or the like. In this case, the first protrusion P1 may be made of a metal material having a high melting point, such as steel or aluminum, so as to protect the pack gasket 130 from the flame F.

[0048] Even when the first protrusion P1 blocks the pack gasket 130 to prevent the pack gasket 130 from being directly exposed to the flame F, the pack gasket 130 may be partially melted by the heat transferred from the side wall frame 112. That is, since the side wall frame 112 is made of a metal material with good thermal conductivity, heat from the side wall frame 112 heated by the flame F may be transferred to the pack gasket 130. In particular, heat may be transferred from the first protrusion P1 adjacent to the flame F to the pack gasket 130 in close contact with the first protrusion P1.

[0049] Considering this, in the modified example of FIG. 5, a gap G1 of a predetermined width is provided between the first protrusion P1 and the pack gasket 130. That is, in FIG. 5, the first protrusion P1 and the pack gasket 130 are not completely in contact with each other, but a small gap is provided to separate the first protrusion P1 and the pack gasket 130. This can prevent heat from the first protrusion P1 from being conducted to the pack gasket 130. In addition, since air can flow through the gap G1, the gap G1 becomes a kind of air cooling flow path in a thermal runaway situation. Therefore, the pack gasket 130 can be more effectively protected from high temperature heat.

[0050] 4 and 5 show how the flange portion 122 of the top lid 120 is coupled to the side wall frame 112 while applying pressure to the pack gasket 130. For ease of explanation, fastening members are not shown in FIG. 4. In FIG. 4 and 5, the height of the first protrusion P1 is shown to be the same as the height of the pack gasket 130.

[0051] However, in a state where the pack gasket 130 is seated on the upper surface 112a of the sidewall frame before fastening the upper lid 120, the height of the pack gasket 130 is preferably higher than the height of the first protrusion P1. That is, the pack gasket 130 is preferably formed to be slightly thicker than the first protrusion P1. In this state, the upper lid 120 covers the upper part of the pack gasket 130 and is coupled to the sidewall frame 112. The upper lid 120 also has a through fastening hole 122a at a position corresponding to the through fastening hole 130a of the pack gasket 130. In addition, the sidewall frame 112 also has a fastening hole at a position corresponding to the through fastening hole 130a of the upper lid 120 and the pack gasket 130. Therefore, the upper lid 120 and the pack gasket 130 are coupled to the upper surface 112a of the sidewall frame by coupling a fastening member B such as a bolt to the through fastening hole 130a and the fastening hole (see FIG. 5). At this time, the upper surface of the pack gasket 130 is pressurized by the joining force of the upper lid 120 joined to the sidewall frame 112. Therefore, before fastening the upper lid 120, the upper surface of the pack gasket 130, which is higher than the height of the first protrusion P1, is pressed and positioned at the same height as the upper surface of the first protrusion. As a result, the pack gasket 130 is compressed between the upper lid 120 and the upper surface of the sidewall frame, filling the space between the upper lid 120 and the sidewall frame 112, thereby exhibiting sealing performance such as watertightness.

[0052] As described above, pack gasket 130 is designed such that gap G1 is formed between first protrusion P1 and the side surface of pack gasket 130 even when pack gasket 130 is compressed.

[0053] Meanwhile, in order to more securely fasten the upper lid 120 and the pack gasket 130, a corresponding screw fastening member N (e.g., a nut) may be fastened to the upper part of the fastening member B. By the fastening member B and the screw fastening member N being coupled, the upper lid 120 is more firmly coupled to the sidewall frame 112. As a result, the pack gasket 130 is also firmly maintained between the upper lid 120 and the upper surface 112a of the sidewall frame, and the sealing performance thereof may be ensured.

[0054] Second embodiment FIG. 6 is an exploded perspective view of a battery pack according to a second embodiment of the present invention, and FIG. 7 is a side sectional view of the battery pack according to the second embodiment.

[0055] In the battery pack 101 of the present embodiment, a second protrusion P2 is provided on an upper surface 112a of the sidewall frame opposite to the first protrusion P1. That is, the second protrusion P2 covering the side surface of the pack gasket 130 opposite to the side surface of the pack gasket 130 blocked by the first protrusion P1 is provided along the upper surface 112a of the sidewall frame. In this case, the pack gasket 130 is installed on the upper surface 112a of the sidewall frame between the first protrusion P1 and the second protrusion P2.

[0056] As described above, the first protrusion P1 protects the pack gasket 130 from the flame F inside the battery pack 100. In this embodiment, the pack gasket 130 is protected by the first protrusion P1 and the second protrusion P2, so that damage to the pack gasket 130 can be more reliably prevented. In addition, the pack gasket 130 is positioned between the first protrusion and the second protrusion, and the pack gasket 130 is restricted between the first protrusion and the second protrusion even after the pack gasket 130 is installed, so that the shape of the pack gasket 130 is stably maintained. In this case, the second protrusion P2 plays a role of restricting the outer surface of the pack gasket 130 from protruding from the side wall frame 112. Therefore, the sealing performance of the pack gasket 130 is guaranteed.

[0057] A second protrusion P2 is also provided on the upper surface 112a of the side wall frame along a side surface of the pack gasket 130. The second protrusion P2 may be rectangular in shape to correspond to the shape of the pack gasket 130.

[0058] Meanwhile, the second protrusion P2 may be molded integrally with the side wall frame 112. Alternatively, the second protrusion P2 may be manufactured separately and coupled to the upper surface 112a of the side wall frame by welding or the like. In this case, the second protrusion P2 may be made of a metal material having a high melting point, such as steel or aluminum, so as to protect the pack gasket 130 from the flame F.

[0059] Also in this embodiment, in order to prevent heat from being transferred from the first protruding portion P1 or the second protruding portion P2 to the pack gasket 130, gaps G1, G2 of a predetermined width can be provided in at least one of between the first protruding portion P1 and the pack gasket 130 and between the second protruding portion P2 and the pack gasket 130. In the example of FIG. 7, gaps G1, G2 are provided both between the first protruding portion P1 and the pack gasket 130 and between the second protruding portion P2 and the pack gasket 130.

[0060] The height of the first protrusion P1 is formed to be the same as the height of the second protrusion P2, so that the heights of the coupling surfaces between the inner surface of the flange portion 122 of the upper lid and the upper surfaces of the first protrusion and the second protrusion are uniform, improving the ease of assembly during fastening.

[0061] When the pack gasket 130 is seated on the upper surface of the sidewall frame before the upper lid 120 is fastened, the height of the pack gasket 130 is higher than the height of the first protrusion P1 and the second protrusion P2. When a fastening member B such as a bolt is coupled to the corresponding through fastening holes 130a of the upper lid 120 and the pack gasket 130 and the fastening hole of the sidewall frame, the upper lid 120 and the pack gasket 130 are coupled to the upper surface 112a of the sidewall frame (see FIG. 7). At this time, the upper surface of the pack gasket 130 is pressed by the coupling force of the upper lid 120 coupled to the sidewall frame 112. As a result, the upper surface of the pack gasket 130, which is higher than the height of the first protrusion P1 and the height of the second protrusion P2 before the upper lid 120 is fastened, is compressed and positioned at the same height as the upper surfaces of the first protrusion P1 and the second protrusion P2. Therefore, the pack gasket 130 is compressed between the upper lid 120 and the upper surface of the side wall frame, filling the space between the upper lid 120 and the side wall frame 112 without any gaps, thereby providing sealing performance such as watertightness.

[0062] In this embodiment, the first protrusion P1 and the second protrusion P2 are located at the same height on both sides of the pack gasket 130, so that the ease of assembly is greatly improved. Conventionally, in order to keep the height of the upper surface of the pack gasket 130 constant when the upper lid 120 presses the pack gasket 130, a bush (not shown) having a flange portion is installed in the fastening hole of the pack gasket 130. That is, when the upper lid 120 is pressed against the pack gasket 130, the flange portion supports the upper lid 120 and prevents the upper lid 120 from descending below the height of the flange portion. This makes it possible to keep the height of the pack gasket 130 compressed between the upper lid 120 and the side wall frame 112 constant.

[0063] In the battery pack 100 of the present embodiment, the first protrusion P1 and the second protrusion P2, which function as flanges of a conventional bush, are located on both sides of the pack gasket 130, and the upper surfaces of the protrusions P1 and P2 form the opposing pressure surfaces of the upper lid 120. The upper lid 120 cannot be lowered below the height of the upper surfaces of the first and second protrusions, and the pack gasket 130 is compressed to the same height as the upper surfaces of the first and second protrusions. As a result, the pack gasket 130 is compressed to a uniform height and has a uniform compression force, improving the sealing performance. As such, the present embodiment has an advantage in that the height of the pack gasket 130 can be maintained constant without a bush, improving the sealing performance.

[0064] Third embodiment FIG. 8 is a partial perspective view of a battery pack 102 according to a third embodiment of the present invention.

[0065] The upper drawing of FIG. 8 shows a state in which the pack gasket 130 is not installed, and the lower drawing of FIG. 8 shows a state in which the pack gasket 130 is installed on the upper surface of the side wall frame.

[0066] As described above, the side wall frame 112 may be assembled by connecting four panels (side wall frame parts) to each other in the front, rear, left and right directions. The adjacent side wall frame parts 112-1 and 112-2 may be arranged vertically to each other, and the ends of each vertically arranged part may be connected to each other by welding. That is, as shown in FIG. 8, the opposing contact surfaces of the vertically arranged side wall frame parts may be connected to each other by welding. Therefore, welds W1 and W2 are formed at the corners of the side wall frame 112 assembled by connecting the side wall frame parts 112-1 and 112-2. Specifically, the welds W1 and W2 may be formed on the upper surface of the corner part of the side wall frame 112 and the side edge of the corner part, respectively. Such welded seams protrude convexly from the upper surface of the side wall frame. If there is a protruding seam as described above, it is difficult to install the pack gasket 130 in close contact with the upper surface 112a of the side wall frame. If the pack gasket 130 is not tightly fitted to the side wall frame 112, a gap will be formed between the pack gasket 130 and the side wall frame 112, reducing watertightness. Therefore, it is necessary to remove the welded seam by surface processing to make the corners of the side wall frame flat.

[0067] The bottom view of FIG. 8 shows that pack gaskets 130 have been installed to remove seams located at the corners of the sidewall frames.

[0068] However, when the first protrusion P1 is located at the corner of the side wall frame as in Fig. 3, or when the first protrusion P1 and the second protrusion P2 are located at the corner of the side wall frame as in Fig. 6, it is very difficult to perform processing to remove the joint at the corner of the side wall frame. That is, when processing to remove the protruding joint, the first protrusion P1 or the first protrusion and the second protrusion P2 get in the way, making it difficult to process the upper surface 112a of the side wall frame flat as desired.

[0069] In consideration of these points, in the battery pack 100 of this embodiment, the upper surface of the side wall frame over a predetermined length range centered on the corner portion of the side wall frame to which the side wall frame parts 112-1, 112-2 are welded is provided with no first protrusion P1 (in the case of the first embodiment), or with no first protrusion P1 or second protrusion P2 (in the case of the second embodiment).

[0070] That is, if there is no protrusion on the upper surface of the side wall frame within a predetermined length range A, A' centered on the corner of the side wall frame as shown in Fig. 8, the protruding weld seam can be easily removed by a processing machine. As a result, the upper surface of the corner of the side wall frame can be processed into a flat surface like the other upper surfaces, and watertightness can be ensured by closely attaching and installing the pack gasket 130 on this flat surface.

[0071] The predetermined length may be determined in consideration of the space in which a processing machine (not shown) can enter the corner of the side wall frame to perform processing work, i.e., the range of the predetermined length may be determined in consideration of the size and working space of the processing machine.

[0072] This embodiment takes into consideration the ease of welding the sidewall frame and the installation of the pack gasket 130. Meanwhile, the corners of the sidewall frame are relatively far from the battery modules M inside the battery pack 100. Therefore, even if a flame F occurs inside the battery pack 100, the influence on the corners of the sidewall frame is small, and therefore the influence of the flame F on the pack gasket 130 installed at the corners of the sidewall frame is also limited.

[0073] (Fourth embodiment) FIG. 9 is a perspective view of a battery pack according to a fourth embodiment of the present invention, FIG. 10 is a perspective view showing a main portion of the battery pack according to the fourth embodiment, FIG. 11 is a partial perspective view of the battery pack according to the fourth embodiment, and FIG. 12 is a partially cut-away perspective view of the battery pack according to the fourth embodiment.

[0074] The battery pack 103 of the present embodiment is characterized in that in the battery pack 100 of the third embodiment, a flame blocking bracket 140 is attached to a corner portion of the upper lid 120 corresponding to a corner portion of the side wall frame, which blocks the corner portion of the side wall frame from the inside of the battery pack 100.

[0075] In the battery pack 100 of the third embodiment, the first protrusion P1 or the second protrusion P2 is not provided at the corner portion of the side wall frame, taking into consideration the welding workability of the side wall frame 112 and the installation of the pack gasket 130. In this case, although the effect of the flame F on the pack gasket 130 installed at the corner portion of the side wall frame is limited, the flame F may also reach the corner portion of the side wall frame.

[0076] In this embodiment, in consideration of the installation of the pack gasket 130, the first protrusion P1 or the second protrusion P2 is not provided at the corner portion of the sidewall frame, but instead, a fire protection bracket 140 that isolates the corner portion of the sidewall frame from the inside of the battery pack 100 is provided on the upper lid 120. That is, by providing the fire protection bracket 140 at the corner portion of the upper lid 120 corresponding to the corner portion of the sidewall frame, the protection of the pack gasket 130 is more reliable. According to this embodiment, the corner portion of the sidewall frame can be easily processed flat, and not only can the installation and watertightness of the pack gasket 130 be maintained, but the first protrusion P1, the second protrusion P2, and the fire protection bracket 140 isolate the pack gasket 130 from the flame F, so that the pack gasket 130 can be more reliably protected.

[0077] The fire protection bracket 140 extends beyond the predetermined length range A, A' where no protrusion is installed so as to block the pack gasket 130 exposed at the corners of the side wall frame where no protrusion is installed.

[0078] The fire protection bracket 140 may be connected to the top lid 120 by, for example, spot welding. The symbol S in Fig. 10 and Fig. 12 indicates a spot welding point or a filler metal part to be spot welded. The material of the fire protection bracket 140 may also be a metal material that can withstand fire. The fire protection bracket 140 may be made of the same or different metal material as the top lid 120.

[0079] As shown in FIG. 10, the fire protection bracket 140 may be composed of a portion coupled to a corner portion of the upper lid and a portion covering a corner portion of the side wall frame. For example, when the upper lid 120 is composed of a flange portion 122 coupled to an upper surface of the side wall frame and a cover portion 121 bent upward from the flange portion 122, the fire protection bracket 140 may be installed at a corner portion of the cover portion 121. Specifically, a portion of the fire protection bracket 140 installed at a corner portion of the upper lid (cover portion 121) may be referred to as an upper plate bracket 142. Also, a portion extending downward from the upper plate bracket 142 and extending along an inner surface of the corner portion of the side wall frame may be referred to as a corner bracket 141. In this embodiment, the fire protection bracket 140 is composed of the upper plate bracket 142 and the corner bracket 141. The corner bracket 141 includes a first bracket portion 141a and a second bracket portion 141b that are arranged perpendicular to each other in accordance with the shape of the corner portion of the side wall frame.

[0080] The corner bracket 141 extends laterally from the corner of the upper lid 120 along the inner surface of the corner of the side wall frame by at least the predetermined length ranges A, A', and extends downward along the inner surface of the corner of the side wall frame to cover the corner of the side wall frame. Therefore, the fire protection bracket 140 completely blocks the corner of the side wall frame where the protrusions P1, P2 are not formed, and effectively protects the pack gasket 130 seated on the corner from fire.

[0081] The fire protection bracket 140 may be installed to be in close contact with the inner surface of the corner of the side wall frame. In this case, the flange portion 122 of the upper lid 120 may be closely coupled to the upper surface 112a of the side wall frame, and the fire protection bracket 140 installed at the corner of the cover portion 121 of the upper lid 120 may be in close contact with the inner surface adjacent to the upper surface of the side wall frame. That is, as shown in Figs. 11 and 12, the upper lid 120 may be coupled to the side wall frame 112 such that the first bracket portion 141a and the second bracket portion 141b of the corner bracket are in close contact with the inner surfaces of the side wall frame parts 112-1 and 112-2 that are vertically arranged to each other.

[0082] However, the fire protection bracket 140 does not necessarily have to be in close contact with the corner of the side wall frame. If the fire protection bracket 140 is large enough, the pack gasket 130 of the side wall corner can be sufficiently protected even if the fire protection bracket 140 is spaced apart from the inner surface of the corner of the side wall frame by a predetermined distance. In addition, in consideration of a predetermined assembly tolerance, the upper lid 120 can be coupled to the side wall frame so that the fire protection bracket 140 is spaced apart from the corner of the side wall frame, thereby improving the ease of assembly of the upper lid and the side wall frame.

[0083] The above description is merely illustrative of the technical idea of ​​the present invention, and various modifications and variations are possible within the scope of the essential characteristics of the present invention if one has ordinary knowledge in the technical field to which the present invention belongs. Therefore, the drawings disclosed in the present invention are for the purpose of explanation, not for the purpose of limiting the technical idea of ​​the present invention, and the scope of the technical idea of ​​the present invention is not limited by such drawings. The scope of protection of the present invention should be interpreted by the claims, and all technical ideas within the scope equivalent thereto should be interpreted as being included in the scope of the present invention.

[0084] Meanwhile, although terms indicating directions such as up, down, left, right, front, and back are used in this specification, it is obvious that these terms are used for convenience of explanation and may change depending on the position of the target object, the position of the observer, etc. [Explanation of symbols]

[0085] 100, 101, 102, 103: Battery pack 110: Lower pack housing 111: Bottom plate 112: Side wall frame 112-1, 112-2: Side wall frame parts 112a: Upper surface of side wall frame 113: Left and right bulkheads 114: Central bulkhead 120: Top lid 121: Cover part 122: Flange part 122a: Through fastening hole M: Battery module 130: Pack gasket 130a: through fastening hole P1: 1st protrusion P2: Second protrusion H: Hollow channel F:Flame G1: Gap G2: Gap B: Fastening member N: Screw connection material W1, W2: Welded section 140: Fire protection bracket 141: Corner bracket 142: Upper plate bracket

Claims

1. a lower pack housing including a bottom plate and a side wall frame surrounding an edge of the bottom plate; an upper lid covering the lower pack housing and coupled to an upper surface of the side wall frame; and A battery pack including a pack gasket installed between an upper surface of the side wall frame and the upper lid, a first protrusion that isolates an interior of the battery pack from the pack gasket is provided along an upper surface of the side wall frame.

2. The battery pack according to claim 1 , wherein a gap of a predetermined width is provided between the first protrusion and the pack gasket.

3. The height of the first protrusion is lower than the height of the pack gasket, 3. The battery pack of claim 1, wherein an upper surface of the pack gasket is pressed by a coupling force of an upper lid coupled to the side wall frame, so that the upper surface of the pack gasket is positioned at the same height as an upper surface of the first protrusion.

4. a second protrusion is provided along an upper surface of the side wall frame for covering a side of the pack gasket opposite to the side of the pack gasket blocked by the first protrusion; The battery pack according to claim 1 , wherein the pack gasket is installed on the upper surface of the side wall frame between the first protrusion and the second protrusion.

5. 5. The battery pack according to claim 4, wherein a gap of a predetermined width is provided at least one of between the first protrusion and the pack gasket and between the second protrusion and the pack gasket.

6. the first protrusion and the second protrusion have the same height that is lower than a height of the pack gasket; 6. The battery pack of claim 4, wherein an upper surface of the pack gasket is pressed by a coupling force of an upper lid coupled to the side wall frame, so that the upper surface of the pack gasket is positioned at the same height as upper surfaces of the first protrusion and the second protrusion.

7. 3. The battery pack of claim 1, wherein the top lid and the pack gasket each have a corresponding through-fastening hole, and a fastening member passes through the through-fastening hole and is coupled to the side wall frame, thereby coupling the top lid and the pack gasket to an upper surface of the side wall frame.

8. The side wall frame is assembled by welding the vertically arranged side wall frame parts together, The battery pack of claim 1 , wherein the first protrusion is not provided on an upper surface of the side wall frame over a predetermined length range centered on a corner portion of the side wall frame to which the side wall frame part is welded.

9. The side wall frame is assembled by welding the vertically arranged side wall frame parts together, 5. The battery pack of claim 4, wherein the first protrusion and the second protrusion are not provided on an upper surface of the side wall frame over a predetermined length range centered on a corner portion of the side wall frame to which the side wall frame part is welded.

10. 10. The battery pack according to claim 8, wherein a fire protection bracket is coupled to a corner portion of the upper lid corresponding to the corner portion of the side wall frame, the fire protection bracket insulating the corner portion of the side wall frame from the inside of the battery pack.

11. The flame blocking bracket comprises: the upper lid extends laterally along an inner surface of the side wall frame from the corner of the upper lid by a length equal to or greater than the predetermined length; and The battery pack according to claim 10 , wherein the support member extends downward along an inner surface of the corner portion of the side wall frame so as to cover the corner portion of the side wall frame.

12. The battery pack according to claim 10 , wherein the upper lid is coupled to the side wall frame such that the fire protection bracket is in close contact with an inner surface of a corner portion of the side wall frame or is spaced apart from the inner surface by a predetermined distance.

13. the upper lid includes a flange portion coupled to an upper surface of the side wall frame, and a cover portion bent upward from the flange portion, The battery pack according to claim 10 , wherein the fire protection bracket is installed at a corner of the cover portion.

14. The flame blocking bracket comprises: an upper plate bracket coupled to the cover; The battery pack according to claim 13 , further comprising: a corner bracket extending downward from the upper plate bracket and extending along an inner surface of a corner portion of the side wall frame.

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