Battery pack

Abstract

The technical idea of the present invention provides a battery pack comprising: a pack housing; a cell assembly including a frame provided on the pack housing and battery cells accommodated in the frame; a mounting block provided between the frame and the pack housing; and a first bolt fastening the frame to the mounting block and spaced apart from the pack housing, wherein the mounting block includes insulating layers provided in a portion in contact with the frame and a portion in contact with the pack housing.

Description

battery pack

[0001] The present invention relates to a battery pack.

[0002] This application claims the benefit of priority based on Korean Patent Application No. 10-2024-0155889 dated November 6, 2024, and all contents disclosed in the documents of said Korean patent applications are incorporated herein as part of this specification.

[0003] Unlike primary batteries, secondary batteries can be charged and discharged multiple times. Secondary batteries are widely used as energy sources for various wireless devices such as handsets, laptops, and cordless vacuum cleaners. Recently, as the manufacturing cost per unit capacity of secondary batteries has decreased dramatically due to improved energy density and economies of scale, and as the driving range of BEVs (battery electric vehicles) has increased to a level equivalent to that of fuel vehicles, the primary use of secondary batteries is shifting from mobile devices to mobility.

[0004] As rechargeable batteries are increasingly used in mobility, demands for their safety are rising. Given that accidents such as fires involving rechargeable batteries in mobility applications can endanger the lives of drivers, research into technologies to enhance battery safety is indispensable.

[0005] The problem that the technical concept of the present invention aims to solve is to provide a battery pack.

[0006] To solve the above-mentioned problem, the technical concept of the present invention provides a battery pack comprising: a pack housing; a cell assembly including a frame provided on the pack housing and battery cells accommodated in the frame; a mounting block provided between the frame and the pack housing; and a first bolt that fastens the frame to the mounting block and is spaced apart from the pack housing, wherein the mounting block includes an insulating layer provided in a portion contacting the frame and a portion contacting the pack housing.

[0007] In exemplary embodiments, the mounting block further comprises a core block, and the insulating layer is characterized by extending along the outer surface of the core block.

[0008] In exemplary embodiments, the first bolt is characterized by being fastened to the core block.

[0009] In exemplary embodiments, the insulating layer is configured to electrically insulate the pack housing from the frame and the first bolt.

[0010] In exemplary embodiments, the mounting block is further characterized by including a second bolt for fastening to the pack housing.

[0011] In exemplary embodiments, the mounting block further comprises a core block to which the first bolt is fastened, and the second bolt is spaced apart from the core block with the insulating layer in between.

[0012] In exemplary embodiments, the mounting block further comprises a core block to which the first bolt is fastened, and the insulating layer comprises: an outer insulating layer extending along the outer surface of the core block and in contact with the frame and the pack housing; and an inner insulating layer extending along a hole in the core block into which the second bolt is inserted.

[0013] In exemplary embodiments, the insulating layer is configured to electrically insulate the second bolt from the core block and the first bolt.

[0014] In exemplary embodiments, the mounting block comprises a hollow portion, and the end of the first bolt is received in the hollow portion of the mounting block.

[0015] In exemplary embodiments, it is characterized by further including a nut coupled to the end of the first bolt received in the hollow portion of the mounting block.

[0016] In exemplary embodiments, the mounting block is further included with a second bolt for fastening to the pack housing, wherein a portion of the second bolt is received in the hollow portion of the mounting block.

[0017] In exemplary embodiments, the mounting block comprises a hollow portion that accommodates the end of the first bolt, and further comprises a nut coupled to the end of the first bolt accommodated in the hollow portion of the mounting block; and a second bolt that fastens the mounting block to the pack housing, with a portion thereof accommodated in the hollow portion of the mounting block.

[0018] According to exemplary embodiments, electrical insulation between the pack housing and the frame of the cell assembly can be maintained by an insulating layer of a mounting block, thereby suppressing the occurrence of electrical short circuits and arcs caused by the frame of the cell assembly being electrically connected to the pack housing. Since thermal transfer between cell assemblies and simultaneous thermal runaway of cell assemblies caused by electrical short circuits and arcs between the frame of the cell assembly and the pack housing can be suppressed, the safety and reliability of the battery pack can be improved.

[0019] The effects obtainable from the exemplary embodiments of the present invention are not limited to those mentioned above, and other unmentioned effects can be clearly derived and understood by those skilled in the art to which the exemplary embodiments of the present disclosure belong from the following description. That is, unintended effects resulting from the implementation of the exemplary embodiments of the present disclosure can also be derived by those skilled in the art from the exemplary embodiments of the present disclosure.

[0020] FIG. 1 is a plan view showing a battery pack according to exemplary embodiments.

[0021] FIG. 2 is a perspective view showing a cell assembly provided in a battery pack according to exemplary embodiments mounted in a pack housing.

[0022] FIG. 3 is a side view showing a cell assembly provided in a battery pack according to exemplary embodiments mounted in a pack housing.

[0023] FIG. 4 is a cross-sectional view showing a cell assembly provided in a battery pack according to exemplary embodiments mounted in a pack housing.

[0024] FIG. 5 is a cross-sectional view showing a cell assembly provided in a battery pack according to exemplary embodiments mounted in a pack housing.

[0025] FIG. 6 is a cross-sectional view showing a cell assembly provided in a battery pack according to exemplary embodiments mounted in a pack housing.

[0026] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. Prior to this, terms and words used in this specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings. Instead, based on the principle that the inventor can appropriately define the concepts of terms to best describe his invention, they should be interpreted in a meaning and concept consistent with the technical spirit of the present invention.

[0027] Therefore, the embodiments described in this specification and the configurations illustrated in the drawings are merely the most preferred embodiments of the present invention and do not represent all of the technical ideas of the present invention; thus, it should be understood that various equivalents and modifications that can replace them may exist at the time of filing this application.

[0028] In addition, in describing the present invention, if it is determined that a detailed description of related known components or functions may obscure the essence of the invention, such detailed description is omitted.

[0029] Since embodiments of the present invention are provided to more fully explain the invention to those skilled in the art, the shapes and sizes of the components in the drawings may be exaggerated, omitted, or schematically depicted for clearer explanation. Accordingly, the size or proportion of each component does not entirely reflect the actual size or proportion.

[0030]

[0031] (1st embodiment)

[0032] FIG. 1 is a plan view showing a battery pack (10) according to exemplary embodiments. FIG. 2 is a perspective view showing a cell assembly (100) provided in a battery pack (10) according to exemplary embodiments mounted in a pack housing (310). FIG. 3 is a side view showing a cell assembly (100) provided in a battery pack (10) according to exemplary embodiments mounted in a pack housing (310). FIG. 4 is a cross-sectional view showing a cell assembly (100) provided in a battery pack (10) according to exemplary embodiments mounted in a pack housing (310).

[0033] Referring to FIGS. 1 to 4, the battery pack (10) may include a cell assembly (100), a pack housing (310), a mounting block (210), and a first bolt (230).

[0034] A cell assembly (100) can be mounted in a pack housing (310). A plurality of cell assemblies (100) may be provided in the pack housing (310), and the plurality of cell assemblies (100) may be arranged in a first horizontal direction (e.g., X-axis direction) and a second horizontal direction (e.g., Y-axis direction).

[0035] The cell assembly (100) may include a cell block (110) comprising a plurality of battery cells (111) and a frame (120).

[0036] An individual battery cell (111) is a basic unit of a lithium-ion battery, i.e., a secondary battery. An individual battery cell (111) may include an electrode assembly, an electrolyte, and a cell case. The electrode assembly embedded in the cell case may include a positive electrode, a negative electrode, and a separator interposed between the positive and negative electrodes. Depending on the assembly form, the electrode assembly may be either a jelly-roll type or a stack type. A jelly-roll type electrode assembly may include a wound structure of a positive electrode, a negative electrode, and a separator interposed between them. A stack type electrode assembly may include a plurality of positive electrodes, a plurality of negative electrodes, and a plurality of separators interposed between them, which are stacked sequentially. The positive electrode may include a positive current collector and a positive active material. The negative electrode may include a negative current collector and a negative active material.

[0037] The individual battery cells (111) may correspond to pouch-type battery cells, cylindrical battery cells, or prismatic battery cells. The electrode assembly of a pouch-type battery cell is embedded in a pouch case containing an aluminum laminate sheet. The electrode assembly of a cylindrical battery cell is embedded in a cylindrical metal can. The electrode assembly of a prismatic battery cell is embedded in a prismatic metal can.

[0038] A plurality of battery cells (111) provided in a cell block (110) may be connected in series and / or in parallel. For example, a plurality of battery cells (111) may be connected in series with each other. For example, a plurality of battery cells (111) may be connected in parallel with each other. For example, when a set of two or more battery cells (111) connected in parallel is defined as a bank, one bank consisting of two or more battery cells (111) connected in parallel with each other and another bank consisting of two or more battery cells (111) connected in parallel with each other may be connected in series.

[0039] In exemplary embodiments, a plurality of battery cells (111) may be arranged in a first horizontal direction (e.g., X-axis direction), and individual battery cells (111) may be extended in a second horizontal direction (e.g., Y-axis direction). An electrode lead may be provided at at least one of the two ends of an individual battery cell (111) along the second horizontal direction (e.g., Y-axis direction). The electrode leads of adjacent battery cells (111) among the plurality of battery cells (111) may be electrically and physically connected to each other.

[0040] The cell block (110) may include a first side and a second side opposite in a first horizontal direction (e.g., X-axis direction), a front and a rear opposite in a second horizontal direction (e.g., Y-axis direction), and a bottom surface and a top surface opposite in a vertical direction (e.g., Z-axis direction). The front surface of the cell block (110) may include the front surfaces of a plurality of battery cells (111), and the rear surface of the cell block (110) may include the rear surfaces of a plurality of battery cells (111). The bottom surface of the cell block (110) may include the bottom surfaces of a plurality of battery cells (111), and the top surface of the cell block (110) may include the top surfaces of a plurality of battery cells (111).

[0041] The frame (120) can accommodate the cell block (110). The frame (120) may include a central frame (121) and a pair of end frames (123). The central frame (121) may surround the cell block (110) to cover the bottom surface, top surface, first side, and second side of the cell block (110). The pair of end frames (123) may be spaced apart in a second horizontal direction (e.g., the Y-axis direction) with the cell block (110) in between. One of the pair of end frames (123) may be attached to the central frame (121) to cover the front of the cell block (110), and the other of the pair of end frames (123) may be attached to the central frame (121) to cover the rear of the cell block (110).

[0042] The pack housing (310) may provide an internal space for accommodating a plurality of cell assemblies (100). The pack housing (310) may include a base plate (311) and a perimeter wall (313).

[0043] A base plate (311) can support a plurality of cell assemblies (100). The base plate (311) may have a flat plate shape extending in a first horizontal direction (e.g., X-axis direction) and a second horizontal direction (e.g., Y-axis direction) perpendicular to each other. A frame (120) of each cell assembly (100) may be attached to the base plate (311) by an adhesive layer (330). For example, the adhesive layer (330) may include a thermal interface material.

[0044] The perimeter wall (313) can be attached to the perimeter of the base plate (311). The perimeter wall (313) can be extended continuously along the perimeter of the base plate (311) to surround a plurality of cell assemblies (100).

[0045] The pack housing (310) may further include a center beam (315). The center beam (315) may be placed on a base plate (311) and may extend in a first horizontal direction (e.g., X-axis direction). Some of the plurality of cell assemblies (100) may be spaced apart in a second horizontal direction (e.g., Y-axis direction) with the center beam (315) in between.

[0046] A mounting block (210) may be provided between the frame (120) of the cell assembly (100) and the pack housing (310). The mounting block (210) may be used for fastening between the frame (120) of the cell assembly (100) and the pack housing (310). The mounting block (210) may be coupled to the base plate (311) of the pack housing (310), and the frame (120) of the cell assembly (100) may be seated on the mounting block (210). The mounting block (210) may be bolted to the base plate (311) of the pack housing (310) or attached to the base plate (311) of the pack housing (310) by an adhesive member such as an adhesive.

[0047] The first bolt (230) can fasten the frame (120) of the cell assembly (100) to the mounting block (210). The first bolt (230) may include a head portion seated on the frame (120) of the cell assembly (100) and a body portion inserted into a through hole of the frame (120) of the cell assembly (100). The first bolt (230) can be inserted into a through hole provided in the frame (120) of the cell assembly (100), and the end portion (231) of the first bolt (230) can be screw-fastened to the mounting block (210). The mounting block (210) may include a hole that accommodates the end (231) of the first bolt (230), and the surface of the mounting block (210) defining the hole of the mounting block (210) may be provided with a thread that engages with the thread provided on the outer circumference of the first bolt (230). The frame (120) of the cell assembly (100) may be fixed to the pack housing (310) via the mounting block (210), and the first bolt (230) may not physically contact the pack housing (310) and may be spaced apart from the pack housing (310). Since the first bolt (230) is not directly connected to the pack housing (310), it is possible to prevent the frame (120) of the cell assembly (100) and the pack housing (310) from being electrically connected through the first bolt (230).

[0048] In exemplary embodiments, a mounting block (210) may be provided between the end frame (123) of the cell assembly (100) and the pack housing (310). The end frame (123) of the cell assembly (100) may be seated on the mounting block (210), and a first bolt (230) may fasten the end frame (123) of the cell assembly (100) to the mounting block (210) coupled to the pack housing (310). The first bolt (230) may be inserted into a through hole (1231) provided in the end frame (123) of the cell assembly (100), and the end (231) of the first bolt (230) may be screwed into the mounting block (210).

[0049] The mounting block (210) may include a core block (211) and an insulating layer (213).

[0050] The core block (211) may include a hole for receiving the end (231) of the first bolt (230) and may be screw-fastened to the end (231) of the first bolt (230). The core block (211) may be formed of a metal such as aluminum or iron.

[0051] The insulating layer (213) may extend along the outer surface of the core block (211) and may cover the outer surface of the core block (211). The insulating layer (213) may be in direct contact with the frame (120) of the pack housing (310) and the cell assembly (100). The insulating layer (213) may cover the core block (211) so that the core block (211) does not come into contact with the frame (120) of the pack housing (310) and the cell assembly (100).

[0052] The insulating layer (213) may be configured to electrically insulate the pack housing (310) from the frame (120) and the first bolt (230) of the cell assembly (100). The insulating layer (213) may be an electrical non-conductor. The insulating layer (213) may comprise insulating plastic, insulating ceramic, an oxide thin film formed through anodizing treatment, or a combination thereof.

[0053] When a thermal event, such as ignition or thermal runaway of a battery cell, occurs in a cell assembly according to a comparative example, the insulation of the cell assembly frame is damaged, and an electrical short circuit and arc occur as the cell assembly frame becomes electrically connected to the pack housing. In particular, in the case of a structure where the cell assembly frame is directly fastened to the pack housing via bolts, an electrical short circuit and arc are likely to occur as the frame is electrically connected to the pack housing via bolts. The aforementioned electrical short circuit and arc accelerate heat transfer between cell assemblies and can cause simultaneous thermal runaway of the cell assemblies.

[0054] According to exemplary embodiments, electrical insulation between the pack housing (310) and the frame (120) of the cell assembly (100) can be maintained by the insulating layer (213) of the mounting block (210), thereby suppressing the occurrence of electrical short circuits and arcs caused by the frame (120) of the cell assembly (100) being electrically connected to the pack housing (310). Since the heat transfer between the cell assemblies (100) and the simultaneous thermal runaway of the cell assemblies (100) caused by the occurrence of electrical short circuits and arcs between the frame (120) of the cell assembly (100) and the pack housing (310) can be suppressed, the safety and reliability of the battery pack (10) can be improved.

[0055] According to exemplary embodiments, the mounting block (210) is coupled to the pack housing (310), and the frame (120) of the cell assembly (100) can be bolted to the mounting block (210). At this time, the frame (120) of the cell assembly (100) is fixed to the pack housing (310) through the mounting block (210), but the first bolt (230) for connecting the cell assembly (100) and the mounting block (210) is spaced apart from the pack housing (310), thereby preventing the frame (120) of the cell assembly (100) and the pack housing (310) from being electrically connected through the first bolt (230).

[0056]

[0057] (2nd Example)

[0058] FIG. 5 is a cross-sectional view showing a cell assembly (100) provided in a battery pack according to exemplary embodiments mounted in a pack housing (310).

[0059] Referring to FIG. 5 together with FIGS. 1 to 3, the mounting block (210A) can be bolted to the pack housing (310). The second bolt (250) can be inserted into a through hole provided in the mounting block (210A), and the end (251) of the second bolt (250) can be screwed to the pack housing (310). The second bolt (250) may include a head portion seated on the mounting block (210A) and a body portion inserted into the through hole of the mounting block (210A). The pack housing (310) may include a hole that accommodates the end (251) of the second bolt (250). The mounting block (210A) can be fixed to the pack housing (310) by engaging the threads provided on the outer surface of the end (251) of the second bolt (250) with the threads provided on the surface of the pack housing (310) that define the hole of the pack housing (310). When the frame (120) of the cell assembly (100) is fastened to the mounting block (210A) by the first bolt (230) and the mounting block (210A) is fastened to the pack housing (310) by the second bolt (250), the frame (120) of the cell assembly (100) can be fixed to the pack housing (310).

[0060] The insulating layer (213A) can electrically insulate the second bolt (250) from the core block (211) and the first bolt (230). The insulating layer (213A) may include an outer insulating layer (2131) extending along the outer surface of the core block (211) and an inner insulating layer (2133) extending along the through hole of the core block (211) into which the second bolt (250) is inserted. The outer insulating layer (2131) may be in direct contact with the frame (120) and pack housing (310) of the cell assembly (100), and may be interposed between the core block (211) and the frame (120) of the cell assembly (100), and between the core block (211) and the pack housing (310). The inner insulating layer (2133) may extend continuously along the surface of the core block (211) defining the through hole of the core block (211) into which the second bolt (250) is inserted. The inner insulating layer (2133) may be interposed between the second bolt (250) and the core block (211) to separate the second bolt (250) from the core block (211) and to electrically insulate the second bolt (250) from the core block (211). Since the second bolt (250) is electrically insulated from the core block (211) by the inner insulating layer (2133) and the outer insulating layer (2131), the second bolt (250) may be electrically insulated from the first bolt (230) and the frame (120).

[0061]

[0062] (3rd Example)

[0063] FIG. 6 is a cross-sectional view showing a cell assembly (100) provided in a battery pack according to exemplary embodiments mounted in a pack housing (310).

[0064] Referring to FIG. 6 together with FIGS. 1 to 3, the mounting block (210B) may include a hollow portion (219). The hollow portion (219) may extend in a second direction between the two portions along the second horizontal direction (e.g., the Y-axis direction) of the mounting block (210B).

[0065] The end (231) of the first bolt (230) can be received in the hollow (219) of the mounting block (210B), and a nut (240) can be screwed into the end (231) of the first bolt (230) received in the hollow (219) of the mounting block (210B). The nut (240) can be fastened to the first bolt (230) by engaging the threads provided on the inner surface of the nut (240) with the threads provided on the outer surface of the first bolt (230). When the nut (240) is coupled to the end (231) of the first bolt (230), the frame (120) of the cell assembly (100) can be fixed to the mounting block (210B). The hollow (219) of the mounting block (210B) can be defined by the surface of the insulating layer (213). In exemplary embodiments, the mounting block (210B) may be formed entirely of an insulating material.

[0066] The mounting block (210B) can be fastened to the pack housing (310) by the second block. The second bolt (250) may include a head portion received in the hollow portion (219) of the mounting block (210B) and a body portion inserted into the hole of the mounting block (210B) and the hole of the pack housing (310). The mounting block (210B) can be fixed to the pack housing (310) by engaging the threads provided on the outer circumference of the end portion (251) of the second bolt (250) with the threads provided on the surface of the pack housing (310) that define the hole of the pack housing (310). When the frame (120) of the cell assembly (100) is fastened to the mounting block (210B) by the first bolt (230) and the mounting block (210B) is fastened to the pack housing (310) by the second bolt (250), the frame (120) of the cell assembly (100) can be fixed to the pack housing (310).

[0067]

[0068] The present invention has been described in more detail above through drawings and embodiments. However, the configurations described in the drawings or embodiments described in this specification are merely one embodiment of the present invention and do not represent all technical concepts of the present invention; therefore, it should be understood that various equivalents and modifications that can replace them may exist at the time of filing this application.

[0069]

[0070] [Explanation of the symbol]

[0071] 10: Battery pack

[0072] 100: Cell assembly

[0073] 110: Cell Block

[0074] 111: Battery cell

[0075] 120: Frame

[0076] 121: Center Frame

[0077] 123: End Frame

[0078] 210, 210A, 210B: Mounting Block

[0079] 211: Core Block

[0080] 213, 213A: Insulation layer

[0081] 219: Ministry of Justice

[0082] 230: 1st Bolt

[0083] 240: Nut

[0084] 250: Second Bolt

[0085] 310: Pack Housing

[0086] 330: Adhesive layer

Claims

1. Pack Housing; A cell assembly comprising a frame provided on the pack housing and battery cells accommodated in the frame; A mounting block provided between the above frame and the above pack housing; and A first bolt spaced apart from the pack housing, which fastens the above frame to the above mounting block; Includes, A battery pack comprising an insulating layer provided on a portion of the mounting block in contact with the frame and a portion in contact with the pack housing.

2. In Paragraph 1, The above mounting block further includes a core block, and A battery pack characterized in that the insulating layer extends along the outer surface of the core block.

3. In Paragraph 2, A battery pack characterized in that the first bolt is fastened to the core block.

4. In Paragraph 1, A battery pack characterized in that the insulating layer is configured to electrically insulate the pack housing from the frame and the first bolt.

5. In Paragraph 1, A battery pack characterized by further including a second bolt for fastening the mounting block to the pack housing.

6. In Paragraph 5, The above mounting block further includes a core block that is fastened to the first bolt, and A battery pack characterized in that the second bolt is spaced apart from the core block with the insulating layer in between.

7. In Paragraph 5, The above mounting block further includes a core block that is fastened to the first bolt, and The above insulating layer is, An outer insulating layer extending along the outer surface of the core block and in contact with the frame and the pack housing; and An internal insulating layer extending along the hole of the core block into which the second bolt is inserted; A battery pack characterized by including 8. In Paragraph 7, A battery pack characterized in that the insulating layer is configured to electrically insulate the second bolt from the core block and the first bolt.

9. In Paragraph 1, The above mounting block includes a hollow portion, and A battery pack characterized in that the end of the first bolt is received in the hollow portion of the mounting block.

10. In Paragraph 9, A nut coupled to the end of the first bolt accommodated in the hollow portion of the mounting block; A battery pack characterized by further including 11. In Paragraph 9, It further includes a second bolt for fastening the above mounting block to the above pack housing, and A battery pack characterized in that a portion of the second bolt is received in the hollow portion of the mounting block.

12. In Paragraph 1, The above mounting block includes a hollow portion that accommodates the end of the first bolt, and A nut coupled to the end of the first bolt received in the hollow portion of the mounting block; and A second bolt that fastens the above mounting block to the above pack housing, with a portion thereof received in the above hollow portion of the above mounting block; A battery pack characterized by further including

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