Battery module and battery pack including same

Abstract

A battery module of the present invention comprises: a battery cell stack comprising a plurality of battery cells; a module frame including a bottom portion and two side portions opposite to each other, and accommodating the battery cell stack therein; a thermally conductive resin layer disposed between one surface of the module frame and the battery cell stack; a pad disposed at at least one end of the one surface of the module frame; and a complementary material disposed between the battery cell stack and the pad, wherein the space between the battery cell stack and the pad is filled with the complementary material.

Description

Battery module and battery pack including same

[0001] Cross-citation with related application(s)

[0002] This application claims the benefit of priority to Korean Patent Application No. 10-2023-0107114, filed August 16, 2023, and Korean Patent Application No. 10-2024-0097888, filed July 24, 2024, the entire contents of which are incorporated herein by reference.

[0003] The present invention relates to a battery module and a battery pack including the same, and more particularly, to a battery module that prevents overflow of a thermally conductive resin and a battery pack including the same.

[0004] Secondary batteries, which boast high electrical properties such as high energy density and easy applicability across a wide range of product groups, are widely used not only in portable devices but also in electric or hybrid vehicles powered by electrical power sources, as well as in power storage devices. These batteries are attracting attention as a new energy source for environmental friendliness and energy efficiency, not only because they can dramatically reduce fossil fuel use, but also because they produce no byproducts from energy use.

[0005] While small mobile devices typically use one, two, or three battery cells per device, medium- to large-sized devices, such as automobiles, require high output and large capacity. Therefore, medium- to large-sized battery modules, which electrically connect multiple battery cells, are used.

[0006] Since it is desirable for medium- to large-sized battery modules to be manufactured with as small a size and weight as possible, square batteries and pouch-type batteries that can be stacked with a high degree of integration and have a small weight per capacity are mainly used as battery cells for medium- to large-sized battery modules. Meanwhile, the battery module may include a frame member that is open at the front and back to accommodate the battery cell stack in an internal space in order to protect the cell stack from external shock, heat, or vibration.

[0007] Figure 1 is an exploded perspective view showing a conventional battery module.

[0008] Figure 2 is a perspective view of a conventional battery cell stack viewed from below.

[0009] Fig. 3 is a cross-sectional view showing a cross-section of the battery module of Fig. 1 cut along the YZ plane.

[0010] Figure 4 is an enlarged cross-sectional view of a portion of Figure 3.

[0011] Referring to FIGS. 1 and 2 together, a conventional battery module (100c) includes a battery cell stack (12) including a plurality of battery cells (11) and a module frame (30) accommodating the battery cell stack (12) therein. The battery cell stack (12) may further include a compression pad (10) disposed between the plurality of battery cells (11), as illustrated in FIG. 3.

[0012] The battery module (100c) may further include an upper plate (not shown) that covers the upper portion of the battery cell stack (120) in combination with the module frame (30), end plates (not shown) positioned respectively on the front and rear sides of the battery cell stack (12), and a busbar frame (13) positioned between the battery cell stack (12) and the end plate (not shown).

[0013] A conventional module frame (30) includes a bottom portion (30a) and two side portions (30b) facing each other. The bottom portion (30a) may have a shape in which the front and back are open along the X-axis direction and the top is open along the Z-axis direction. The side portions (30b) may extend in the Z-axis direction from both sides of the bottom portion (30a). The bottom portion (30a) and the side portions (30b) form a space for storing a battery cell stack (12).

[0014] Meanwhile, before the battery cell stack (12) is mounted on the module frame (30), a thermally conductive resin layer (31) can be formed between the module frame (30) and the battery cell stack (12). The thermally conductive resin layer (31) can transfer heat generated from the battery cell stack (12) to the outside of the battery module and serve to fix the battery cell stack within the battery module.

[0015] The thermally conductive resin layer (31) can be formed by applying and curing thermally conductive resin to the bottom portion (30a) of the module frame (30). Meanwhile, when applying the thermally conductive resin, a pad (32) can be placed on the bottom portion (30a) to prevent the thermally conductive resin from overflowing beyond a required area. The pads (32) are placed at both ends of the bottom portion (30a) to control the application direction of the thermally conductive resin. However, in the process of spreading the thermally conductive resin, there are cases where it spreads beyond the application area beyond the pad (32).

[0016] Referring to FIGS. 3 and 4 together, after the battery cell stack (12) is mounted on the module frame (30), there is a space (SP) that is not completely filled between the pad (32) and the battery cell stack (12). The thermally conductive resin may overflow out of the pad (32) through this space (SP) during the application process. In this case, the battery cell stack (12) may be damaged, and the performance of the battery cell stack (12) may deteriorate and safety issues may occur.

[0017] Therefore, it is necessary to develop a structure that can control the overflow of the thermally conductive resin during the formation process of the thermally conductive resin layer.

[0018] The problem to be solved by the present invention is to provide a battery module that prevents overflow of a thermally conductive resin and a battery pack including the same.

[0019] However, the problems to be solved by the embodiments of the present invention are not limited to the problems described above and can be expanded in various ways within the scope of the technical ideas included in the present invention.

[0020] The battery module of the present invention comprises: a battery cell stack including a plurality of battery cells; a module frame including a bottom portion and two side portions facing each other and accommodating the battery cell stack therein; a thermally conductive resin layer disposed between one surface of the module frame and the battery cell stack; a pad disposed on at least one end of the one surface of the module frame; and a supplementary material disposed between the battery cell stack and the pad; wherein the supplementary material fills a space between the battery cell stack and the pad.

[0021] In one embodiment, the surface may be an upper surface of the bottom portion.

[0022] In one embodiment, the one surface may be an inner surface of the side surface.

[0023] In one embodiment, the complementary material may comprise a resin.

[0024] In one embodiment, the thermally conductive resin layer may not overflow outside the pad and the complementary material.

[0025] In one embodiment, the complementary material may be first provided on one surface of the battery cell stack in an uncured state, and then formed by being compressed and cured between the battery cell stack and the pad when the battery cell stack is housed in the module frame.

[0026] In one embodiment, the supplementary material may be polyurethane foam (PU foam).

[0027] In one embodiment, the complementary material may be silicone.

[0028] In one embodiment, the pads may be arranged in multiple numbers on both ends of the one side of the module frame, and the thermally conductive resin layer may be arranged between the pads.

[0029] The battery pack of the present invention includes the battery module described above.

[0030] The battery module of the present invention includes a supplementary material that fills the space between the battery cell stack and the pad, thereby preventing the thermally conductive resin from flowing into an unintended space when the battery cell stack is inserted into the module frame.

[0031] Figure 1 is an exploded perspective view showing a conventional battery module.

[0032] Figure 2 is a perspective view of a conventional battery cell stack viewed from below.

[0033] Fig. 3 is a cross-sectional view showing a cross-section of the battery module of Fig. 1 cut along the YZ plane.

[0034] Figure 4 is an enlarged cross-sectional view of a portion of Figure 3.

[0035] Figure 5 is a plan view showing a battery pack of one embodiment.

[0036] Figure 6 is an exploded perspective view showing a battery module according to one embodiment.

[0037] Fig. 7 is a perspective view showing a combined battery module in which the components illustrated in Fig. 6 are combined.

[0038] Figure 8 is a perspective view of the battery module of Figure 6 viewed from below.

[0039] Fig. 9 is a cross-sectional view showing a cross-section of the battery module of Fig. 7 taken along the YZ plane.

[0040] Fig. 10 is an enlarged cross-sectional view of a portion of Fig. 9.

[0041] Hereinafter, various embodiments of the present invention will be described in detail with reference to the attached drawings so that those skilled in the art can easily implement the invention. The present invention may be implemented in various different forms and is not limited to the embodiments described herein.

[0042] In order to clearly explain the present invention, parts that are not related to the description are omitted, and the same reference numerals are used for identical or similar components throughout the specification.

[0043] Furthermore, the sizes and thicknesses of each component shown in the drawings are arbitrarily indicated for convenience of explanation, and thus the present invention is not necessarily limited to the illustrated components. In the drawings, the thicknesses are enlarged to clearly represent various layers and regions. Furthermore, in the drawings, the thicknesses of some layers and regions are exaggerated for convenience of explanation.

[0044] Furthermore, when we say that a layer, membrane, region, plate, or other part is "on" or "over" another part, this includes not only cases where it is "directly on" the other part, but also cases where there are other parts in between. Conversely, when we say that a part is "directly on" another part, we mean that there are no other parts in between. Furthermore, saying that a part is "on" or "over" a reference part means that it is located above or below the reference part, and does not necessarily mean that it is located "above" or "over" the reference part in the opposite direction of gravity.

[0045] Additionally, throughout the specification, whenever a part is said to "include" a component, this does not mean that it excludes other components, but rather that it may include other components, unless otherwise specifically stated.

[0046] Additionally, throughout the specification, when we say "in plan", we mean when the target portion is viewed from above, and when we say "in cross section", we mean when the target portion is viewed from the side in a cross-section cut vertically.

[0047] Figure 5 is a plan view showing a battery pack of one embodiment.

[0048] Referring to FIG. 5, a battery pack (1000) according to one embodiment includes battery modules (100), a pack frame (1100), a busbar assembly (1200), a BDU (battery disconnect unit) module (1300) for controlling electrical connection of the battery modules (100), and a BMS (battery management system) module (1400) for monitoring and controlling operation of the battery modules (100). At least one busbar assembly (1200) according to the present embodiment electrically connects at least one of battery modules (100), between a battery module (100) and a BDU module (1300), between a battery module (100) and a BMS module (1400), and between a BDU module (1300) and a BMS module (1400). Specifically, a plurality of battery modules (100) can be housed in a pack frame (1100), and electrical connections between the battery modules (100) or electrical connections between the battery modules (100) and the BDU module (1300) can be made by a busbar assembly (1200). That is, the busbar assembly (1200) according to the present embodiment can be responsible for HV (High voltage) connections. Here, the HV connection refers to a connection that serves as a power source for supplying power requiring high voltage, and refers to a connection between battery cells or a connection between battery modules.

[0049] Meanwhile, the BDU module (1300) is a member for controlling the electrical connection of the battery module (100) and can cut off power between the power conversion device and the battery module (100). The BDU module (1300) can cut off power to the battery pack (1000) when a condition occurs in which the current exceeds a set range, thereby ensuring the safety of the battery pack (1000).

[0050] Meanwhile, the LV connecting member (1200') according to the present embodiment can be responsible for the electrical connection between the battery module (100) and the BMS module (1400). The electrical connection here is a LV (Low voltage) connection, which means a sensing connection for detecting and controlling the voltage and temperature of the battery module (100). Specifically, sensors, etc. are arranged inside the battery module (100), and real-time temperature information or voltage information of the battery module (100) is transmitted to the BMS module (1400) through the LV connecting member (1200'). The real-time operating status of the battery module (100) can be monitored and controlled through the BMS module (1400). Although not specifically illustrated, there are cases where an HV current sensor is integrated into the BMS module (1400). In this case, the busbar assembly according to the present embodiment can be responsible for electrical connection between the battery module (100) and the BMS module (1400) or between the BDU module (1300) and the BMS module (1400).

[0051] Hereinafter, a battery module according to one embodiment will be described with reference to FIGS. 6 to 10. However, the battery module (100) described below is an exemplary structure of a battery module including a battery cell stack (120), and various types of battery modules including a battery cell stack (120) can be applied.

[0052] Figure 6 is an exploded perspective view showing a battery module according to one embodiment.

[0053] Fig. 7 is a perspective view showing a combined battery module in which the components illustrated in Fig. 6 are combined.

[0054] Figure 8 is a perspective view of the battery module of Figure 6 viewed from below.

[0055] Fig. 9 is a cross-sectional view showing a cross-section of the battery module of Fig. 7 taken along the YZ plane.

[0056] Fig. 10 is an enlarged cross-sectional view of a portion of Fig. 9.

[0057] Referring to FIGS. 6 and 7 together, a battery module (100) according to the present embodiment includes a battery cell stack (120) including a plurality of battery cells (110) and a module frame (300) accommodating the battery cell stack (120) therein. The battery cell stack (120) includes a plurality of battery cells (110) stacked in one direction, and for example, the plurality of battery cells (110) may be stacked in the Y-axis direction as illustrated in FIG. 6. The battery cells (110) may be pouch-type battery cells, but the embodiment of the present invention is not limited thereto. Meanwhile, the battery cell stack (120) may further include a compression pad (111) disposed between the plurality of battery cells (110), as illustrated in FIG. 9. The compression pad (111) may include a foam or the like to absorb swelling of the battery cells (110) and improve the structural stability of the battery module (100).

[0058] The battery module (100) may further include an upper plate (400) that covers the upper portion of the battery cell stack (120) by being combined with the module frame (300), an end plate (150) positioned on the front and rear sides of the battery cell stack (120), and a busbar frame (130) positioned between the battery cell stack (120) and the end plate (150).

[0059] The battery module (100) includes a thermally conductive resin layer (310) positioned between the battery cell stack (120) and the module frame (300). The thermally conductive resin layer (310) may be a thermally conductive adhesive. Various organic and / or inorganic resins such as a thermally conductive epoxy adhesive, a thermally conductive silicone adhesive, and a thermally conductive urethane adhesive may be employed as the thermally conductive adhesive. The thermally conductive resin layer (310) may serve to adhesively fix the battery cell stack (120) within the battery module (100). In addition, since the thermally conductive resin layer (310) has a higher thermal conductivity than a general adhesive, it may further increase the amount and speed of heat transfer between the battery cell stack (120) and the module frame (30), and may serve as a heat dissipation layer that transfers heat generated from the battery cell stack (120) to the outside of the battery module (100). The thermally conductive resin layer (310) is positioned between one surface of the battery cell stack (120) and the module frame (300).

[0060] The module frame (300) may have an open shape on the upper surface, front surface, and rear surface. The module frame (300) may be a U-shaped frame. When the open sides of the module frame (300) are referred to as the first side and the second side, respectively, the module frame (300) is formed of a plate-like structure that is folded to continuously wrap the front, lower surface, and rear surface that are adjacent to each other among the remaining outer surfaces, excluding the surfaces of the battery cell stack (120) corresponding to the first side and the second side. The upper surface opposite the lower surface of the module frame (300) is open.

[0061] A pad (320) is arranged on the above surface of the module frame (300) to guide the position of application of the thermally conductive resin during the process of forming the thermally conductive resin layer (310).

[0062] The module frame (300) includes a bottom portion (300a) and two side portions (300b) facing each other. As described above, the thermally conductive resin layer (310) is disposed between one surface of the module frame (300) and the battery cell stack (120). The one surface of the module frame (300) may be either the upper surface of the bottom portion (300a) or the inner surface of the side portion (300b). The upper surface of the bottom portion (300a) may be the surface facing the lower surface of the battery cell stack (120). The inner surface of the side portion (300b) may be the surface facing the front and rear surfaces of the battery cell stack (120). In one embodiment, the thermally conductive resin layer (310) may be disposed between the upper surface of the bottom portion (300a) of the module frame (300) and the battery cell stack (120). Alternatively, in another embodiment, the thermally conductive resin layer (310) may be placed between the inner surface of the side portion (300b) of the module frame (300) and the battery cell stack (120).

[0063] Hereinafter, as an example, a thermally conductive resin layer (310) is described as being placed on the upper surface of the bottom portion (300a) of the module frame (300). That is, a structure in which a thermally conductive resin layer (310), a pad (320), and a supplementary material (RS) to be described later are placed on the bottom portion (300a) is described as an example.

[0064] However, the embodiment of the present invention is not limited thereto, and the thermally conductive resin layer (310) may be arranged on the inner surface of the side portion (300b) rather than the bottom portion (300a). In this case, the description of the relationship between the thermally conductive resin layer (310), the pad (32), and the complementary material (RS) described below applies equally.

[0065] In one embodiment, referring to FIG. 6, the thermal conductive resin layer (310) is formed by being applied lengthwise in the X-axis direction, which is the extension direction of the bottom portion (300a), on the bottom portion (300a).

[0066] The pad (320) is arranged on at least one end of the bottom portion (300a). For example, the pad (320) may be arranged on both ends of the bottom portion (300a) to guide the position of application of the thermally conductive resin during the formation of the thermally conductive resin layer (310) or to prevent the thermally conductive resin from overflowing to the outside of the pad (320). In FIG. 6, one pad (320) is illustrated as being formed on each end of the bottom portion (300a), but the size, position, number, etc. of the pads (320) may be designed to be modified in consideration of the amount of thermally conductive resin applied, etc. The pad (320) may have insulating properties. In addition, when the battery cell stack (120) is inserted into the module frame (300), the pad (320) may be formed of a material such as polyurethane foam (PU foam) or rubber so that the pad (320) that touches the bottom surface of the battery cell stack (120) can be compressed.

[0067] The upper plate (400) is formed as a single plate-like structure that surrounds the upper surface except for the front, lower, and rear surfaces that are surrounded by the module frame (300). The module frame (300) and the upper plate (400) can form a structure that surrounds the battery cell stack (120) by being joined by welding or the like while their corresponding corner portions are in contact with each other. That is, the module frame (300) and the upper plate (400) can form a joining portion (CP) formed by a joining method such as welding at their corresponding corner portions.

[0068] Referring to FIGS. 6, 8, 9, and 10 together, a supplementary material (RS) is disposed between the battery cell stack (120) and the pad (320) of one embodiment. In order to explain the position where the supplementary material (RS) is formed, the pad (320) is omitted in FIG. 8. The supplementary material (RS) may be disposed along the Y-axis direction, which is the extension direction of the pad (320). The supplementary material (RS) fills the space (SP, see FIG. 3) between the battery cell stack (120) and the pad (320) when the battery cell stack (120) is accommodated in the module frame (300). The space (SP, see FIG. 3) refers to a gap between the battery cell stack (120) and the pad (320). The supplementary material (RS) can prevent the thermally conductive resin layer (310) from overflowing out of the pad (320) through the space (SP, see FIG. 3).

[0069] The supplementary material (RS) may include a resin. For example, the supplementary material (RS) may be polyurethane foam (PU foam) formed by spraying polyurethane on one side, for example, the lower surface, of the battery cell laminate (120). Alternatively, the supplementary material (RS) may be silicone formed by using a silicone gun on one side, for example, the lower surface, of the battery cell laminate (120). However, the material of the supplementary material (RS) is not limited to the above, and any material having insulating properties and a predetermined compressibility may be used.

[0070] The supplementary material (RS) may be first provided on one side, for example, the lower side, of the battery cell stack (120) in an uncured state, and then formed by being compressed and cured between the battery cell stack (120) and the pad (320) when the battery cell stack (120) is housed in the module frame (300). The supplementary material (RS) may fill the space (SP, see FIG. 3) between the battery cell stack (120) and the pad (320) during the compression process.

[0071]

[0072] The battery module (100) of the present invention includes a supplementary material (RS) disposed between a battery cell stack (120) and a pad (320) disposed on a bottom portion (300a) of a module frame (300), thereby filling the space between the battery cell stack (120) and the pad (320) with the supplementary material (RS) and effectively controlling overflow of a thermally conductive resin. Accordingly, it is possible to prevent defects in the battery module (100) caused by formation of a thermally conductive resin layer (310) in an unintended portion.

[0073]

[0074] In this example, terms indicating directions such as front, back, left, right, up, and down are used, but these terms are only for convenience of explanation and may vary depending on the location of the target object or the location of the observer.

[0075] One or more battery modules according to the above-described embodiment can be mounted together with various control and protection systems such as a BMS (Battery Management System), a BDU (Battery Disconnect Unit), and a cooling system to form a battery pack.

[0076] The above battery module or battery pack can be applied to various devices. Specifically, it can be applied to transportation vehicles such as electric bicycles, electric vehicles, and hybrid vehicles, as well as ESS (Energy Storage Systems), but is not limited thereto. It can also be applied to various devices that can use secondary batteries.

[0077] 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 concept of the present invention defined in the following claims also fall within the scope of the present invention.

[0078] [Explanation of symbols]

[0079] 100: Battery module

[0080] 120: Battery cell stack

[0081] 110: Battery cell

[0082] 111: Compression pad

[0083] 300: Module Frame

[0084] 300a: Bottom

[0085] 300b: Side

[0086] 310: Thermally conductive resin layer

[0087] 320: Pad

[0088] 400: Top plate

[0089] RS: Complementary goods

Claims

1. A battery cell stack comprising a plurality of battery cells; A module frame comprising a bottom portion and two side portions facing each other and accommodating the battery cell stack therein; A thermally conductive resin layer disposed between one side of the module frame and the battery cell laminate; a pad arranged on at least one side of the above module frame; and Complementary material disposed between the battery cell stack and the pad; The above complementary material is a battery module that fills the space between the battery cell stack and the pad.

2. In paragraph 1, The above one side is the upper surface of the above bottom part, the battery module.

3. In paragraph 1, The above one side is the inner surface of the side surface of the battery module.

4. In paragraph 1, The above complementary material is a battery module containing a resin.

5. In paragraph 1, A battery module in which the thermally conductive resin layer does not overflow beyond the outside of the pad and the complementary material.

6. In paragraph 1, A battery module formed by first providing the supplementary material on one side of the battery cell laminate in an uncured state, and then compressing and curing between the battery cell laminate and the pad when the battery cell laminate is accommodated in the module frame.

7. In paragraph 1, The above-mentioned supplementary material is a battery module made of polyurethane foam (PU foam).

8. In paragraph 1, The above supplementary material is a battery module made of silicone.

9. In paragraph 1, The above pads are arranged in multiples on both ends of the above one side of the above module frame, The above thermally conductive resin layer is a battery module disposed between the pads.

10. A battery pack comprising a battery module according to paragraph 1.

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