Battery pack and device including the same

Abstract

A battery pack according to one embodiment of the present application includes a battery module including a plurality of battery cells, a battery pack frame for accommodating the battery module, and a holding bracket for fixing the battery module to the battery pack frame. The holding bracket includes a first fastening portion fastened to the battery module, a second fastening portion fastened to the battery pack frame, a connecting portion for connecting the first fastening portion and the second fastening portion, and a reinforcing member coupled to the connecting portion. The connecting portion and the reinforcing member coupled together have a closed structure.

Description

Technical Field

[0001] Cross-reference to related applications

[0002] This application claims the benefit of Korean Patent Application 10-2021-0004508, filed with the Korean Intellectual Property Office on January 13, 2021, the entire contents of which are incorporated herein by reference.

[0003] The present invention relates to a battery pack and an apparatus including the battery pack, and more particularly to a battery pack having improved structural safety and an apparatus including the battery pack. Background Technology

[0004] In modern society, the widespread use of portable devices such as mobile phones, laptops, portable camcorders, and digital cameras has spurred technological development in areas related to these mobile devices. Furthermore, rechargeable / dischargeable secondary batteries are being used as power sources for electric vehicles (EVs), hybrid electric vehicles (HEVs), and plug-in hybrid electric vehicles (P-HEVs) in an attempt to address issues such as air pollution caused by existing gasoline vehicles using fossil fuels. Therefore, there is a growing demand for the development of secondary batteries.

[0005] Currently commercially available rechargeable batteries include nickel-cadmium (NiCd), nickel-metal hydride (NiMH), nickel-zinc (NiZn), and lithium-ion batteries. Among these, lithium-ion batteries have attracted attention because they offer advantages such as exhibiting almost no memory effect compared to nickel-based batteries, allowing for free charging and discharging, and possessing very low self-discharge rates and high energy density.

[0006] This type of lithium secondary battery mainly uses lithium-based oxide and carbonaceous materials as positive and negative electrode active materials, respectively. The lithium secondary battery includes an electrode assembly and a battery casing. In the electrode assembly, positive and negative electrode plates, respectively coated with positive and negative electrode active materials, are provided with a separator inserted between them. The battery casing seals and contains the electrode assembly together with the electrolyte solution.

[0007] Generally, based on the shape of the external material, lithium secondary batteries can be divided into can-type secondary batteries with electrode components built into a metal can and bag-type secondary batteries with electrode components built into a bag made of aluminum laminate.

[0008] In the case of secondary batteries for small devices, two to three battery cells are used. However, in the case of secondary batteries for medium or large devices such as automobiles, battery modules in which a large number of battery cells are electrically connected are used. In such battery modules, a large number of battery cells are connected in series or parallel to form battery packs, thereby increasing capacity and output. In addition, one or more battery modules can be installed together with various control and protection systems such as battery management systems (BMS) and cooling systems to form battery packs.

[0009] Because the battery pack is internally integrated and houses various internal components, space constraints arise within the pack, making it difficult to ensure the rigidity of the structure used to secure the battery modules within. A technical solution is needed to improve the structural safety of the battery pack within its confined space. Summary of the Invention

[0010] Technical issues

[0011] One object of the present invention is to provide a battery pack equipped with a battery module fastening structure, which can be used in the confined space of the battery pack and is also durable.

[0012] However, the problems to be solved by the embodiments of the present invention are not limited to the above-mentioned problems, and various extensions can be made within the scope of the technical ideas included in the present invention.

[0013] Technical solution

[0014] According to an embodiment of the present invention, a battery pack is provided, comprising: a battery module including a plurality of battery cells; a battery pack frame for accommodating the battery module; and a retaining bracket for securing the battery module to the battery pack frame, wherein the retaining bracket includes: a first fastening portion fastened to the battery module; a second fastening portion fastened to the battery pack frame; a connecting portion for connecting the first fastening portion and the second fastening portion; and a reinforcing member connected to the connecting portion, wherein the connecting portion and the reinforcing member connected to each other have a closed structure.

[0015] The connecting portion may have a downwardly curved structure with an open upper portion, and the reinforcing member may be connected to the connecting portion to form a double-plate structure with a closed shape.

[0016] The reinforcing member may have a structure that bends upward and has an open lower part.

[0017] The side surface of the connecting part and the side surface of the reinforcing member can be welded together in an overlapping manner.

[0018] The battery module may include an upper battery module and a lower battery module, and the upper battery module may be stacked on the lower battery module.

[0019] The first fastening part of the retaining bracket can be fastened to the upper battery module.

[0020] The connecting portion may include an upwardly bent section.

[0021] The width of the first fastening part can be wider than the width of the second fastening part.

[0022] The connecting portion can narrow as it moves from the first fastening portion toward the second fastening portion.

[0023] Beneficial effects

[0024] According to an embodiment of the present invention, the battery module fastening structure is made into a closed structure, thereby ensuring the rigidity of the battery module fastening structure even in the confined space inside the battery pack.

[0025] The effects of the present invention are not limited to those described above, and those skilled in the art will clearly understand from the description of the appended claims other effects not described above. Attached Figure Description

[0026] Figure 1 This is a partial perspective view showing a battery pack according to an embodiment of the present invention;

[0027] Figure 2 It is shown that it includes Figure 1 A 3D view of the battery modules in the battery pack;

[0028] Figure 3 It is shown that it includes Figure 2 A 3D view of the battery cells in the battery module;

[0029] Figure 4 It is shown that it includes Figure 1 A 3D view of the retaining bracket in the battery pack;

[0030] Figure 5 yes Figure 4 An exploded 3D view of the retainer;

[0031] Figure 6 It shows along Figure 4 A cross-sectional view of the section cut by the cutting line AA;

[0032] Figure 7 It is shown Figure 1 A cross-sectional view of the battery pack in the xz plane;

[0033] Figure 8 This is a perspective view showing a retaining bracket according to a comparative example of the present invention; and

[0034] Figure 9 It shows that it is equipped with Figure 8 A cross-sectional view of the battery pack holding the support in the xz plane. Detailed Implementation

[0035] In the following description, various embodiments of the invention will be detailed with reference to the accompanying drawings, enabling those skilled in the art to readily implement them. The invention can be modified in various different ways and is not limited to the embodiments set forth herein.

[0036] For clarity, descriptions of parts irrelevant to the description will be omitted here, and the same reference numerals will denote the same elements throughout the description.

[0037] Furthermore, for ease of explanation, the dimensions and thicknesses of each element are arbitrarily shown in the accompanying drawings, and the invention is not necessarily limited to those shown in the drawings. For clarity, the thicknesses of layers, regions, etc., are exaggerated in the accompanying drawings. For ease of description, the thicknesses of certain layers and regions are magnified in the accompanying drawings.

[0038] Furthermore, it should be understood that when an element such as a layer, membrane, region, or plate is referred to as being "on" or "above" another element, it can be directly on the other element, or there may be intermediate elements present. Conversely, when an element is referred to as being "directly on another element," it means that there are no other intermediate elements present. Additionally, the terms "on" or "above" imply that it is positioned above or below a reference portion, and do not necessarily mean that it is positioned at the upper end of the reference portion facing the opposite direction of gravity.

[0039] Furthermore, throughout the specification, when a section is referred to as "including" a component, it means that the section may further include other components, but does not exclude other components, unless otherwise stated.

[0040] Furthermore, throughout the instruction manual, when referred to as a "plane," it means when the target portion is viewed from above, and when referred to as a "cross section," it means when the target portion is viewed from the side of a vertically cut cross section.

[0041] Figure 1 This is a partial perspective view showing a battery pack according to an embodiment of the present invention. Figure 2 It is shown that it includes Figure 1 A 3D view of the battery modules in the battery pack. Figure 3 It is shown that it includes Figure 2 A 3D view of the battery cells in the battery module.

[0042] Reference Figures 1 to 3 According to an embodiment of the present invention, a battery pack includes: a battery module 100, the battery module 100 including a plurality of battery cells 110; a battery pack frame 200 for housing the battery module 100; and a retaining bracket 300 for fixing the battery module 100 to the battery pack frame 200.

[0043] The battery module 100 can be formed by housing a plurality of battery cells 110 within a module frame 120. The battery cells 110 are preferably pouch-type battery cells. For example, the battery cell 110 according to this embodiment has a structure in which two electrode leads 111 and 112 face each other and protrude from one end 114a and the other end 114b of the cell body 113, respectively. More specifically, the electrode leads 111 and 112 are connected to an electrode assembly (not shown) and protrude from the electrode assembly (not shown) to the outside of the battery cell 110.

[0044] Simultaneously, the battery cell 110 can be manufactured by joining the two ends 114a and 114b of the battery cell housing 114 and a side portion 114c connecting the two ends 114a and 114b, with the electrode assembly (not shown) housed in the battery cell housing 114. In other words, the battery cell 110 according to this embodiment has a total of three sealing portions 114sa, 114sb, and 114sc, which have a structure sealed by a method such as thermal welding, and the remaining side portion can be formed by a bending portion 115. The battery cell housing 114 can be formed from a laminate including a resin layer and a metal layer.

[0045] Furthermore, the bend 115 may extend along one edge of the battery cell 110, and a protrusion 110p, referred to as a "batwing ear," may be formed at the end of the bend 115. Multiple battery cells 110 may be constructed, and these cells may be stacked to be electrically connected to each other.

[0046] Meanwhile, in the battery pack according to this embodiment, multiple battery modules 100 are configured and can be housed within the battery pack frame 200. Furthermore, when multiple battery modules 100 are housed within the battery pack frame 200, a two-layer structure can be formed. In other words, the battery module 100 can include an upper battery module 100a and a lower battery module 100b, wherein the upper battery module 100a can be stacked on top of the lower battery module 100b. The lower battery module 100b can be stacked on the battery pack frame 200.

[0047] Meanwhile, the battery module 100 may include mounting portions 100Ma and 100Mb. Specifically, the upper battery module 100a may include the mounting portion 100Ma, and the lower battery module 100b may also include the mounting portion 100Mb. Bolts or the like can be inserted into the mounting portion 100Mb of the lower battery module 100b and fastened to the battery pack frame 200. Because the upper battery module 100a is located on the lower battery module 100b, the upper battery module 100a can be fastened by a retaining bracket 300 as a separate fastening member, rather than being directly fastened to the battery pack frame 200.

[0048] Next, the retaining bracket 300 according to this embodiment will be described in detail.

[0049] Figure 4 It is shown that it includes Figure 1 A three-dimensional view of the retaining bracket in the battery pack. Figure 5 yes Figure 4 An exploded 3D view of the support structure. Figure 6 It shows along Figure 4 The cross-sectional view of the section cut by the cutting line AA. Figure 7 It is shown Figure 1 A cross-sectional view of the battery pack taken along the xz plane.

[0050] See Figure 1 as well as Figures 4 to 7 The retaining bracket 300 according to this embodiment includes: a first fastening portion 310 fastened to the battery module 100; a second fastening portion 320 fastened to the battery pack frame 200; a connecting portion 330 for connecting the first fastening portion 310 and the second fastening portion 320; and a reinforcing member 400 connected to the connecting portion 330. At this time, the connecting portion 330 and the reinforcing member 400, which are connected to each other, have a closed structure.

[0051] At least one first through hole 310H can be formed in the first fastening part 310 for inserting a bolt B1. The first fastening part 310 can be fastened to the battery module 100 by means of a bolt B1 passing through the first through hole 310H. At this time, the first fastening part 310 can be fastened to the upper battery module 100a of the battery module 100, and the bolt B1 passing through the first through hole 310H can be connected to the mounting part 100Ma of the upper battery module 100a. That is, the upper battery module 100a located at the upper part of the battery module 100 forming a two-layer structure can be fastened to the battery pack frame 200 by means of a retaining bracket 300.

[0052] At least one second through hole 320H can be formed in the second fastening part 320, into which a bolt can be inserted. The second fastening part 320 can be fastened to the battery pack frame 200 by means of a bolt B2 passing through the second through hole 320H.

[0053] At the same time, such as Figure 4 and Figure 5 As shown, the connecting portion 330 according to this embodiment can have a downwardly curved structure with an open upper portion, or it can be composed of a single layer. That is, since the connecting portion is composed of a single layer, it has an open shape at both the upper and lower parts. Meanwhile, the reinforcing member 400 can have a structure that is upwardly curved with an open lower portion. The reinforcing member 400 can be attached to the connecting portion 330 to form a closed double-plate structure.

[0054] In the connection between the connecting part 330 and the reinforcing member 400, the side surface of the connecting part 330 and the side surface of the reinforcing member 400 can be welded together in an overlapping manner, such as... Figure 6 As shown.

[0055] Meanwhile, as described above, the first fastening portion 310 and the second fastening portion 320 of the retaining bracket 300 can be fastened to the upper battery module 100a and the battery pack frame 200, respectively, thereby the connecting portion 330 for connecting the first fastening portion 310 and the second fastening portion 320 may include a portion bent in the upward direction. The reinforcing member 400 can be connected to this portion bent in the upward direction.

[0056] Meanwhile, the width of the first fastening part 310 can be wider than the width of the second fastening part 320. In one example, such as Figure 4 As shown, the first fastening portion 310 has a relatively wide width, wide enough to form four first through holes 310H, while the second fastening portion 320 has a relatively narrow width, narrow enough to form only one second through hole 320H. The width of the fastening portion or the number of through holes is not particularly limited and can vary according to the design; however, as mentioned above, the width of the first fastening portion 310 can be wider than the width of the second fastening portion 320. Therefore, the connecting portion 330 according to this embodiment can have a shape in which the width narrows from the first fastening portion 310 toward the second fastening portion 320.

[0057] To meet the needs of miniaturization and increased energy density of battery packs, multiple components must be centrally arranged within the battery pack, and the utilization of space within the battery pack has become a factor directly related to its performance. In this context, the utilization rate of internal space can be improved by reducing the width of the second fastening portion 320 fixed to the battery pack frame 200. On the other hand, for stable mounting of the battery module 100, the first fastening portion 310 directly fastened to the battery module 100 preferably has a width that corresponds to a certain extent to the width of the battery module 100. Therefore, the retaining bracket 300 according to this embodiment can have a shape where the width of the first fastening portion 310 is wider than the width of the second fastening portion 320, in order to balance the space utilization requirements within the battery pack and the stable fixing requirements of the battery module 100.

[0058] Next, the function of the reinforcing member 400 according to this embodiment will be described in detail by comparison with the retaining bracket 30 of the comparative example according to the present invention.

[0059] Figure 8 This is a perspective view showing a retaining bracket according to a comparative example of the present invention. Figure 9 It shows a device equipped with cutting along the xz plane. Figure 8 A cross-sectional view of the battery pack holding the support.

[0060] First, see Figure 8 The retaining bracket 30 according to a comparative example of the present invention includes a first fastening portion 31, a second fastening portion 32, and a connecting portion 33. It has a structure similar to that of the retaining bracket 300 according to this embodiment, except that the reinforcing member is not connected to the connecting portion 33.

[0061] Let's refer to each other. Figure 8 and Figure 9 By using the retaining bracket 30 according to this comparative example, the battery module 100 can be secured to the battery pack frame 200. Specifically, the battery module 100 may include an upper battery module 100a and a lower battery module 100b having a two-layer structure, and the first fastening portion 31 of the retaining bracket 30 can be connected to the mounting portion 100Ma of the upper battery module 100a by bolt B1. The second fastening portion 32 of the retaining bracket 30 can be connected to the battery pack frame 200 by bolt B2.

[0062] The battery module 100 located inside the battery pack may exhibit vertical displacement due to external impacts or vibrations. Based on this displacement, the load may concentrate on the connecting portion 33 that connects the first fastener 31 and the second fastener 32. At this time, because the connecting portion 33, which bends downwards and has an open upper portion, is particularly weak, the connecting portion 33 may be damaged due to the concentrated load.

[0063] On the other hand, see Figure 1 and Figure 7 The retaining bracket 300 according to this embodiment includes a reinforcing member 400 coupled to the connecting portion 330. As described above, the load generated due to the displacement of the battery module 100 may be concentrated on the connecting portion 330, which is bent downwards and has an open upper portion, thus exhibiting relatively weak rigidity. To compensate for the lack of rigidity, simply increasing the thickness of the connecting portion could be considered, but increasing the thickness alone has limitations. Therefore, the reinforcing member 400, which bends upwards and has an open lower portion, can be coupled to the connecting portion 330 to form a closed double-plate structure, thereby ensuring the rigidity of the connecting portion 330.

[0064] Specifically, as described above, the connecting portion 330 according to this embodiment includes a portion bent in the upward direction and has a shape in which the width narrows from the first fastening portion 310 toward the second fastening portion 320. This could be a factor that weakens the rigidity of the connecting portion 330, but in this embodiment, the rigidity of the connecting portion 330 is compensated by the connecting reinforcing member 400. At this time, the reinforcing member 400 may include a portion bent in the upward direction, such as... Figure 5 As shown, it can have a shape in which the width narrows from the first fastening part 310 toward the second fastening part 320. That is, the shape of the reinforcing member 400 can be configured to correspond to the shape of the connecting part 330.

[0065] In addition to the battery module, the battery pack according to the present invention may include various control and protection systems, such as BDU (battery disconnect unit), BMS (battery management system) and cooling system.

[0066] The battery pack according to the present invention can be applied to various devices. Specifically, these devices can be applied to vehicle devices such as electric bicycles, electric vehicles, and hybrid vehicles, but the present invention is not limited thereto and can be applied to various devices that can use secondary batteries.

[0067] Although this embodiment uses terms such as front, back, left, right, up, and down to indicate direction, it will be apparent to those skilled in the art that these are merely for ease of explanation and may vary depending on the observer's position, the object's position, etc.

[0068] Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements made by those skilled in the art using the basic concepts of the present invention as defined in the appended claims are also within the scope of the present invention.

[0069] Explanation of reference numerals in the attached figures

[0070] 100: Battery Module

[0071] 200: Battery pack frame

[0072] 300: Maintain the support

[0073] 400: Reinforcing component

Claims

1. A battery pack, the battery pack comprising: The battery module includes multiple battery cells; Battery pack frame for housing the battery module; as well as A retaining bracket is provided for securing the battery module to the battery pack frame. The retaining bracket includes: a first fastening part fastened to the battery module; a second fastening part fastened to the battery pack frame; a connecting part for connecting the first fastening part and the second fastening part; and a reinforcing member connected to the connecting part. The connecting portion has a downwardly curved structure with an open upper portion, and the reinforcing member has an upwardly curved structure with an open lower portion, such that the connecting portion and the reinforcing member, which are connected to each other, have a closed shape in a cross-section taken along the width direction of the retaining bracket.

2. The battery pack according to claim 1, wherein, The reinforcing member is connected to the connecting part to form a double-plate structure with a closed shape.

3. The battery pack according to claim 1, wherein, The side surface of the connecting part and the side surface of the reinforcing member are welded together in an overlapping manner.

4. The battery pack according to claim 1, wherein, The battery module includes an upper battery module and a lower battery module, and The upper battery module is stacked on top of the lower battery module.

5. The battery pack according to claim 4, wherein, The first fastening part of the retaining bracket is fastened to the upper battery module.

6. The battery pack according to claim 5, wherein, In the cross-section, the connecting portion includes a portion that bends upwards.

7. The battery pack according to claim 1, wherein, The width of the first fastening part is wider than the width of the second fastening part.

8. The battery pack according to claim 7, wherein, The width of the connecting portion narrows as it moves from the first fastening portion toward the second fastening portion.

9. The battery pack according to claim 6, wherein, In the cross-section, the reinforcing member is connected to the portion of the connection that is bent in the upward direction.

10. An apparatus comprising a battery pack according to any one of claims 1 to 9.

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