Battery module and battery pack including the same

Abstract

The battery module of the present invention comprises a battery cell stack including a plurality of battery cells, a bottom portion and two side portions facing each other, a module frame that accommodates the battery cell stack inside, a thermally conductive resin layer disposed between one side of the module frame and the battery cell stack, a pad disposed at least one end of one side of the module frame, and a complementary material disposed between the battery cell stack and the pad, wherein the complementary material fills the space between the battery cell stack and the pad.

Description

Technology Field

[0001] The present invention relates to a battery module and a battery pack including the same, and more specifically, to a battery module that prevents overflow of a thermally conductive resin and a battery pack including the same. Background Technology

[0002] Secondary batteries, which possess electrical characteristics such as high energy density and high applicability across product categories, are widely applied not only to portable devices but also to electric vehicles or hybrid vehicles powered by electric sources, and power storage devices. These secondary batteries are attracting attention as a new energy source for enhancing eco-friendliness and energy efficiency, not only for the primary advantage of drastically reducing the use of fossil fuels but also because they generate no by-products from energy use.

[0003] While small mobile devices use one or two or three battery cells per device, medium-to-large devices such as automobiles require high output and large capacity. Therefore, medium-to-large battery modules in which multiple battery cells are electrically connected are used.

[0004] Since it is desirable for medium-to-large battery modules to be manufactured with the smallest possible size and weight, prismatic batteries, pouch-type batteries, etc., which can be stacked with high integration density and have a low weight-to-capacity ratio, are mainly used as battery cells for medium-to-large battery modules. Meanwhile, the battery module may include a frame member that houses the battery cell stack in an internal space, with the front and rear sides open, to protect the cell stack from external shock, heat, or vibration.

[0005] FIG. 1 is an exploded perspective view showing a conventional battery module.

[0006] FIG. 2 is a perspective view of a conventional battery cell stack viewed from below.

[0007] Figure 3 is a cross-sectional view showing a cross-section of the battery module of Figure 1 cut along the YZ plane.

[0008] Figure 4 is a cross-sectional view showing an enlarged portion of Figure 3.

[0009] Referring to FIG. 1 and FIG. 2 together, a conventional battery module (100c) includes a battery cell stack (12) comprising a plurality of battery cells (11) and a module frame (30) that accommodates the battery cell stack (12) inside. The battery cell stack (12) may further include a compression pad (10) disposed between the plurality of battery cells (11), as shown in FIG. 3.

[0010] The battery module (100c) may further include an upper plate (not shown) that covers the upper part of the battery cell stack (120) in combination with the module frame (30), end plates (not shown) located on the front and rear of the battery cell stack (12), respectively, and a busbar frame (13) located between the battery cell stack (12) and the end plates (not shown).

[0011] 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 rear 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 accommodating a battery cell stack (12).

[0012] 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.

[0013] A thermally conductive resin layer (31) can be formed by applying and curing a thermally conductive resin on the bottom portion (30a) of the module frame (30). Meanwhile, when applying the thermally conductive resin, a pad (32) may be placed on the bottom portion (30a) to prevent the thermally conductive resin from overflowing outside the required area. The pad (32) is placed at both ends of the bottom portion (30a) to control the direction of application of the thermally conductive resin. However, during the process of spreading the thermally conductive resin, it may spread beyond the pad (32) to areas outside the application area.

[0014] Referring to FIGS. 3 and FIGS. 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). During the application process, the thermally conductive resin may overflow out of the pad (32) through this space (SP). In this case, the battery cell stack (12) may be damaged, and performance degradation and safety issues may occur.

[0015] Therefore, it is necessary to develop a structure capable of controlling the overflow of the thermally conductive resin during the formation process of the thermally conductive resin layer. The problem to be solved

[0016] The problem that the present invention aims to solve is to provide a battery module in which the overflow of a thermally conductive resin is prevented and a battery pack including the same.

[0017] However, the problems that the embodiments of the present invention aim to solve 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. means of solving the problem

[0018] 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 inside; a thermally conductive resin layer disposed between one side of the module frame and the battery cell stack; a pad disposed at least at one end of the one side of the module frame; and a complementary material disposed between the battery cell stack and the pad; wherein the complementary material fills the space between the battery cell stack and the pad.

[0019] In one embodiment, the one surface may be the upper surface of the bottom portion.

[0020] In one embodiment, the one surface may be the inner surface of the side portion.

[0021] In one embodiment, the complement may include a resin.

[0022] In one embodiment, the thermally conductive resin layer may not overflow to the outside of the pad and the complement.

[0023] In one embodiment, the supplementary material may first be provided on one side of the battery cell stack in an uncured state, and then formed by compression and curing between the battery cell stacks and the pads when the battery cell stack is housed in the module frame.

[0024] In one embodiment, the complementary material may be polyurethane foam (PU foam).

[0025] In one embodiment, the complementary material may be silicone.

[0026] In one embodiment, the pads are arranged in plurality at both ends of one side of the module frame, and the thermally conductive resin layer may be arranged between the pads.

[0027] The battery pack of the present invention includes the battery module described above. Effects of the invention

[0028] The battery module of the present invention includes a complementary 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. Brief explanation of the drawing

[0029] FIG. 1 is an exploded perspective view showing a conventional battery module. FIG. 2 is a perspective view of a conventional battery cell stack viewed from below. Figure 3 is a cross-sectional view showing a cross-section of the battery module of Figure 1 cut along the YZ plane. Figure 4 is a cross-sectional view showing an enlarged portion of Figure 3. FIG. 5 is a plan view showing a battery pack of one embodiment. FIG. 6 is an exploded perspective view showing a battery module according to one embodiment. FIG. 7 is a combined perspective view showing a battery module in which the components shown in FIG. 6 are combined. Fig. 8 is a perspective view of the battery module of Fig. 6 viewed from below. Figure 9 is a cross-sectional view showing a cross-section of the battery module of Figure 7 cut along the YZ plane. Figure 10 is a cross-sectional view showing an enlarged portion of Figure 9. Specific details for implementing the invention

[0030] 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 present invention. The present invention may be embodied in various different forms and is not limited to the embodiments described herein.

[0031] To clearly explain the present invention, parts unrelated to the explanation have been omitted, and the same reference numerals are used for identical or similar components throughout the specification.

[0032] Furthermore, the size and thickness of each component shown in the drawings are depicted arbitrarily for convenience of explanation, and thus the present invention is not necessarily limited to what is illustrated. Thicknesses have been enlarged in the drawings to clearly represent various layers and regions. Additionally, for convenience of explanation, the thickness of some layers and regions has been exaggerated in the drawings.

[0033] Furthermore, when a part such as a layer, membrane, region, or plate is said to be "on" or "on" another part, this includes not only the case where it is "directly above" the other part, but also the case where there is another part in between. Conversely, when a part is said to be "directly above" another part, it means that there is no other part in between. Also, saying that a part is "on" or "on" a reference part means that it is located above or below the reference part, and does not necessarily mean that it is located "on" or "on" facing the opposite direction of gravity.

[0034] Furthermore, throughout the specification, when a part is described as "including" a certain component, this means that, unless specifically stated otherwise, it does not exclude other components but may include additional components.

[0035] Additionally, throughout the specification, "planar" means when the subject part is viewed from above, and "cross-sectional" means when the cross-section obtained by vertically cutting the subject part is viewed from the side.

[0036] FIG. 5 is a plan view showing a battery pack of one embodiment.

[0037] 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 battery disconnect unit (BDU) module (1300) for controlling the electrical connection of the battery modules (100), and a battery management system (BMS) module (1400) for monitoring and controlling the operation of the battery modules (100). At least one busbar assembly (1200) according to this embodiment electrically connects at least one of the battery modules (100), the battery modules (100) and the BDU module (1300), the battery modules (100) and the BMS module (1400), and the BDU module (1300) and the 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 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, an HV connection refers to a connection that serves as a power source to supply power requiring high voltage, and refers to a connection between battery cells or between battery modules.

[0038] Meanwhile, the BDU module (1300) is a component for controlling the electrical connection of the battery module (100) and can cut off power between the power converter and the battery module (100). The BDU module (1300) can ensure the safety of the battery pack (1000) by cutting off power to the battery pack (1000) when a condition occurs where the current exceeds a set range.

[0039] Meanwhile, the LV connection member (1200') according to the present embodiment may be responsible for the electrical connection between the battery module (100) and the BMS module (1400). The electrical connection here refers to a LV (Low voltage) connection, meaning a sensing connection for detecting and controlling the voltage and temperature of the battery module (100). Specifically, sensors such as those inside the battery module (100) are placed, and real-time temperature information or voltage information of the battery module (100) is transmitted to the BMS module (1400) through the LV connection 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 the electrical connection between the battery module (100) and the BMS module (1400) or between the BDU module (1300) and the BMS module (1400).

[0040] 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) may be applied.

[0041] FIG. 6 is an exploded perspective view showing a battery module according to one embodiment.

[0042] FIG. 7 is a combined perspective view showing a battery module in which the components shown in FIG. 6 are combined.

[0043] Fig. 8 is a perspective view of the battery module of Fig. 6 viewed from below.

[0044] Figure 9 is a cross-sectional view showing a cross-section of the battery module of Figure 7 cut along the YZ plane.

[0045] Figure 10 is a cross-sectional view showing an enlarged portion of Figure 9.

[0046] Referring to FIGS. 6 and FIGS. 7 together, a battery module (100) according to the present embodiment includes a battery cell stack (120) comprising a plurality of battery cells (110) and a module frame (300) that accommodates the battery cell stack (120) inside. 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 shown in FIG. 6. The battery cells (110) may be pouch-type battery cells, but the embodiments of the present invention are 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 shown in FIG. 9. The compression pad (111) may include foam, etc., to absorb swelling of the battery cells (110) and improve the structural stability of the battery module (100).

[0047] The battery module (100) may further include an upper plate (400) that covers the upper part of the battery cell stack (120) in combination with the module frame (300), end plates (150) located on the front and rear of the battery cell stack (120), respectively, and a busbar frame (130) located between the battery cell stack (120) and the end plates (150).

[0048] The battery module (100) includes a thermally conductive resin layer (310) located 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 thermally conductive epoxy adhesive, thermally conductive silicone adhesive, and thermally conductive urethane adhesive, may be used as the thermally conductive adhesive. This thermally conductive resin layer (310) can serve to fix the battery cell stack (120) within the battery module (100). Additionally, because the thermally conductive resin layer (310) has a higher thermal conductivity than a general adhesive, it can further increase the amount and speed of heat transfer between the battery cell stack (120) and the module frame (30), and 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 placed between one side of the battery cell stack (120) and the module frame (300).

[0049] The module frame (300) may have a shape in which the top surface, front surface, and rear surface are open. The module frame (300) may be a U-shaped frame. When the two open sides of the module frame (300) are referred to as the first side and the second side, the module frame (300) is formed as a plate-shaped structure that is folded to continuously wrap the adjacent front surface, bottom surface, and rear surface among the remaining outer surfaces, excluding the surfaces of the battery cell stack (120) corresponding to the first side and the second side. The top surface facing the bottom surface of the module frame (300) is open.

[0050] A pad (320) is disposed on one side of the module frame (300) to guide the application position of the thermally conductive resin during the formation process of the thermally conductive resin layer (310).

[0051] The module frame (300) includes a bottom portion (300a) and two side portions (300b) facing each other. As described above, a thermally conductive resin layer (310) is disposed between one side of the module frame (300) and the battery cell stack (120). One side 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 a surface facing the lower surface of the battery cell stack (120). The inner surface of the side portion (300b) may be a 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).

[0052] In the following description, as an example, a thermally conductive resin layer (310) is disposed on the upper surface of the bottom portion (300a) of the module frame (300). That is, a structure in which the thermally conductive resin layer (310), a pad (320), and a supplementary material (RS) to be described later are disposed on the bottom portion (300a) is described as an example.

[0053] However, embodiments of the present invention are not limited thereto, and the thermally conductive resin layer (310) may be disposed on the inner surface of the side portion (300b) rather than the bottom portion (300a). In this case as well, the description of the relationship between the thermally conductive resin layer (310), the pad (32), and the complementary material (RS) described below applies in the same way.

[0054] In one embodiment, referring to FIG. 6, a thermally conductive resin layer (310) is formed by being applied long in the X-axis direction, which is the extension direction of the bottom portion (300a), on the bottom portion (300a).

[0055] A pad (320) is placed at least one end of the bottom portion (300a). For example, the pad (320) is placed at both ends of the bottom portion (300a) to guide the application position of the thermal conductive resin during the formation process of the thermal conductive resin layer (310) or to prevent the thermal conductive resin from overflowing outside the pad (320). Although FIG. 6 shows one pad (320) formed at each end of the bottom portion (300a), the size, position, and number of pads (320) can be modified and designed considering the amount of thermal conductive resin applied. The pad (320) may have insulating properties. Additionally, when the battery cell stack (120) is inserted into the module frame (300), the pad (320) may be formed from a material such as polyurethane foam (PU foam) or rubber so that the pad (320) in contact with the bottom surface of the battery cell stack (120) can be compressed.

[0056] The upper plate (400) is formed as a single plate-shaped structure that covers the upper surface, excluding the front, bottom, and rear surfaces that are covered by the module frame (300). The module frame (300) and the upper plate (400) can form a structure that covers the battery cell stack (120) by joining them by welding or the like while their corresponding corner portions are in contact. That is, the module frame (300) and the upper plate (400) can have a joint portion (CP) formed by a joining method such as welding at their corresponding corner portions.

[0057] Referring together to FIGS. 6, FIGS. 8, FIGS. 9, and FIGS. 10, a complementary material (RS) is disposed between a battery cell stack (120) and a pad (320) of one embodiment. To explain the location where the complementary material (RS) is formed, the pad (320) is omitted in FIG. 8. The complementary material (RS) may be disposed along the Y-axis direction, which is the extension direction of the pad (320). The complementary material (RS) serves to fill the space (SP, see FIG. 3) between the battery cell stack (120) and the pad (320) when the battery cell stack (120) is housed in a module frame (300). The space (SP, see FIG. 3) refers to the gap between the battery cell stack (120) and the pad (320). By means of the complementary material (RS), the thermally conductive resin layer (310) can be prevented from overflowing out of the pad (320) through the space (SP, see FIG. 3).

[0058] The complementary material (RS) may include a resin. For example, the complementary material (RS) may be a polyurethane foam (PU foam) formed by spraying a polyurethane spray, etc., onto one side of the battery cell laminate (120), for example, the bottom surface. Alternatively, the complementary material (RS) may be silicone formed by using a silicone gun, etc., onto one side of the battery cell laminate (120), for example, the bottom surface. However, the material of the complementary material (RS) is not limited to the above, and any material having insulating properties and a certain compressibility is acceptable.

[0059] The complementary material (RS) can be formed by first being provided on one side, for example, the bottom side, of the battery cell stack (120) in an uncured state, and then 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). During the compression process, the complementary material (RS) can fill the space (SP, see FIG. 3) between the battery cell stack (120) and the pad (320).

[0061] The battery module (100) of the present invention includes a complementary material (RS) disposed between a battery cell stack (120) and a pad (320) disposed on the bottom portion (300a) of a module frame (300), thereby filling the space between the battery cell stack (120) and the pad (320) with the complementary material (RS) and effectively controlling the overflow of the thermally conductive resin. Accordingly, defects in the battery module (100) caused by the formation of a thermally conductive resin layer (310) in unintended areas can be prevented.

[0063] In this embodiment, terms indicating directions such as front, back, left, right, up, and down have been used; however, these terms are for convenience of explanation only and may vary depending on the location of the object or the position of the observer.

[0064] One or more battery modules according to the embodiment described above can be mounted together with various control and protection systems, such as a Battery Management System (BMS), a Battery Disconnect Unit (BDU), and a cooling system, to form a battery pack.

[0065] The above battery module or battery pack can be applied to various devices. Specifically, it can be applied to means of transportation such as electric bicycles, electric vehicles, and hybrids, or to Energy Storage Systems (ESS), but is not limited thereto and can be applied to various devices capable of using secondary batteries.

[0066] Although 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 by those skilled in the art using the basic concept of the present invention as defined in the following claims also fall within the scope of the present invention. Explanation of the symbols

[0067] 100: Battery module 120: Battery cell stack 110: Battery cell 111: Compression pad 300: Module Frame 300a: Bottom part 300b: Side 310: Thermally conductive resin layer 320: Pad 400: Upper plate RS: Complementary

Claims

Claim 1 A battery module comprising: 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 inside; a thermally conductive resin layer disposed between one side of the module frame and the battery cell stack; a pad disposed at least one end of the one side of the module frame; and a complementary material disposed between the battery cell stack and the pad at the at least one end, wherein the complementary material fills the space between the battery cell stack and the pad at a position corresponding to the pad. Claim 2 In claim 1, the above-mentioned surface is the upper surface of the bottom portion of the battery module. Claim 3 In claim 1, the above-mentioned one surface is the inner surface of the above-mentioned side portion of the battery module. Claim 4 In paragraph 1, the above-mentioned complement is a battery module comprising a resin. Claim 5 In claim 1, the thermally conductive resin layer does not overflow to the outside of the pad and the complementary material of the battery module. Claim 6 A battery module formed in claim 1, wherein the supplementary material is first provided to one side of the battery cell stack in an uncured state, and then compressed and cured between the battery cell stacks and between the pads when the battery cell stack is housed in the module frame. Claim 7 In paragraph 1, the battery module is a complementary material which is polyurethane foam (PU foam). Claim 8 In claim 1, the above-mentioned complement is a battery module made of silicon. Claim 9 A battery module according to claim 1, wherein the pads are arranged in plurality at both ends of one side of the module frame, and the thermally conductive resin layer is arranged between the pads. Claim 10 A battery pack comprising a battery module according to any one of claims 1 to 9.

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