Battery module and battery pack including the same

Abstract

The present disclosure provides a battery module and a battery pack including the battery module. A battery module according to an embodiment of the present disclosure includes: a battery cell stack having a plurality of battery cells stacked in a first direction; a module frame for accommodating the battery cell stack; a first thermally conductive resin layer positioned between the battery cell stack and a lower portion of the module frame; and a second thermally conductive resin layer positioned between the battery cell stack and an upper portion of the module frame, wherein at least one liquid injection hole for injecting thermally conductive resin is formed in the upper portion of the module frame, wherein at least one shielding pad is positioned on a lower surface of the upper portion of the module frame, and wherein the shielding pad is open in a central portion thereof and surrounds the liquid injection hole.

Description

Technical Field

[0001] The present disclosure relates to a battery module and a battery pack including the same, and more particularly, to a battery module with improved cooling performance and a battery pack including the same. Background Art

[0002] With the development of technology and the increasing demand for mobile devices, the demand for batteries as energy sources is rapidly increasing. In particular, secondary batteries are attracting attention as energy sources for power-driven devices such as electric bicycles, electric vehicles, and hybrid electric vehicles, as well as for mobile devices such as mobile phones, digital cameras, laptops, and wearable devices.

[0003] Small mobile devices use one or more battery cells per device, while medium or large devices such as vehicles require high power and large capacity. Therefore, medium or large battery modules with multiple battery cells electrically connected to each other are used.

[0004] Medium- and large-sized battery modules are preferably manufactured to be as small and light as possible. Therefore, prismatic batteries, pouch-shaped batteries, and other materials that can be stacked with high integration density and are relatively lightweight relative to their capacity are primarily used as battery cells for medium- and large-sized battery modules. Furthermore, to protect the battery cell stack from external shock, heat, or vibration, the battery module may include a module frame that houses the battery cell stack within its interior.

[0005] Figure 1 is an exploded perspective view showing a conventional battery module. Figure 2 It shows the composition Figure 1 A perspective view of a state in which components of a battery module are assembled.

[0006] Reference Figure 1 and Figure 2 A conventional battery module 10 includes: a battery cell stack 12 having a plurality of battery cells 11 stacked in one direction; a module frame for accommodating the battery cell stack 12; end plates 15 covering the front and rear surfaces of the battery cell stack; and a busbar frame 13 formed between the front and rear surfaces of the end plates 15 and the battery cell stack 12. The module frame includes a lower frame 30 covering the lower portion and both side surfaces of the battery stack 12, and an upper plate 40 covering the upper surface of the battery cell stack 12. The battery module 10 is configured so that a thermally conductive resin layer 31 can be applied to the lower surface of the battery cell stack 12 in the lower frame 30, thereby cooling the heat generated in the battery cell stack 12.

[0007] Figure 3 It is along Figure 2 Cross-sectional view of cutting line AA.

[0008] Reference Figure 1 and Figure 3 Conventional battery module 10 has a structure that cools the lower portion of battery cell stack 12. This structure allows heat generated in battery cells 11 to flow downward along a first cooling direction D1. However, because thermally conductive resin layer 31 is formed only at locations corresponding to the lower portion of battery cell stack 12, the temperature of battery cells 11 near thermally conductive resin layer 31 is low, while the temperature of battery cells 11 farther from thermally conductive resin layer 31 is high. This creates a temperature difference within battery cells 11. Specifically, the temperature increases toward the upper portion and both ends of battery cells 11, while the temperature decreases toward the lower portion and center of battery cells 11.

[0009] In particular, because the positive and negative electrodes are located at the ends of the battery cells 11, they generate relatively more heat than the center during the charge / discharge process of the battery module 10. However, from the perspective of cooling only the heat transferred to the lower portions of the battery cells 11 at the ends, the thermally conductive resin layer 31 located below the battery cells 11 cannot sufficiently and quickly cool the heat generated at the ends of the battery cells 11. In particular, considering that the temperature of the battery cells 11 is one of the factors that limit battery output, localized temperature increases in the battery cells 11 are likely to prematurely limit battery output, thus requiring improvement. Summary of the Invention

[0010] Technical issues

[0011] An object of the present disclosure is to provide a battery module having improved cooling performance of battery cells and a battery pack including the same.

[0012] The objects of the present disclosure are not limited to the above objects, and those skilled in the art will clearly understand other objects not described herein through the following detailed description and accompanying drawings.

[0013] Technical Solution

[0014] According to one embodiment of the present disclosure, a battery module is provided, comprising: a battery cell stack in which a plurality of battery cells are stacked along a first direction; a module frame for accommodating the battery cell stack; a first thermally conductive resin layer located between the battery cell stack and a lower portion of the module frame; and a second thermally conductive resin layer located between the battery cell stack and an upper portion of the module frame, wherein at least one liquid injection hole for injecting thermally conductive resin is formed in an upper portion of the module frame, wherein at least one shielding pad is located on a lower surface of the upper portion of the module frame, and wherein a central portion of the shielding pad is open and the shielding pad surrounds the liquid injection hole.

[0015] The second thermally conductive resin layer may be formed of a thermally conductive resin injected into the at least one liquid injection hole.

[0016] The second thermally conductive resin layer may be surrounded by a shielding pad.

[0017] The liquid injection hole and the shielding pad may be located at an upper portion of the module frame closer to one end portion than to a central portion.

[0018] The liquid injection hole and the shielding pad may be located at a corner of one side end portion at an upper portion of the module frame.

[0019] The battery module may further include bus bar frames respectively located on the front and rear surfaces of the battery cell stack, and end plates covering the bus bar frames, wherein the first bus bar is attached to a central portion of the bus bar frame and the second bus bars are respectively attached to both side portions of the bus bar frame.

[0020] The second bus bar may be a terminal bus bar.

[0021] The liquid injection hole and the shielding pad may be located adjacent to the second bus bar, respectively.

[0022] The module frame includes a U-shaped frame including a bottom surface and two side surfaces connected to both sides of the bottom surface; and an upper plate for covering the battery cell stack attached to the U-shaped frame, the upper portion of the module frame being the upper plate.

[0023] The first thermally conductive resin layer is formed by coating a thermally conductive resin on the bottom surface of the U-shaped frame or attaching a heat transfer pad.

[0024] According to one embodiment of the present disclosure, a battery pack is provided, comprising the above-mentioned battery module.

[0025] Beneficial effects

[0026] According to an embodiment of the present disclosure, a thermally conductive resin layer is formed in an upper portion of a battery cell stack, thereby making it possible to suppress a local temperature rise in the battery cells and reduce a temperature difference.

[0027] The effects of the present disclosure are not limited to the above-described effects, and additional other effects that are not described above will be clearly understood by those skilled in the art from the description of the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 is an exploded perspective view showing a conventional battery module;

[0029] Figure 2 It shows the composition Figure 1 A perspective view of a state in which components of a battery module are assembled;

[0030] Figure 3 It is along Figure 2 A cross-sectional view of the cutting line AA;

[0031] Figure 4 is an exploded perspective view of a battery module according to an embodiment of the present invention;

[0032] Figure 5 It shows the composition Figure 4 A perspective view of a state in which components of a battery module are assembled;

[0033] Figure 6 It shows Figure 4 A perspective view of a state in which the upper portion of the module frame of the battery module is turned upside down;

[0034] Figure 7 It shows Figure 4 FIG. 1 is a diagram of a busbar frame of a battery module;

[0035] Figure 8 It is shown from Figure 4 A perspective view of a battery module with the upper portion of the module frame removed; and

[0036] Figure 9 It is along Figure 5 Cross-sectional view of cutting line BB. DETAILED DESCRIPTION

[0037] Hereinafter, various embodiments of the present disclosure will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily implement these embodiments. The present disclosure can be modified in various ways and is not limited to the embodiments set forth herein.

[0038] Parts irrelevant to the description will be omitted to clearly describe the present disclosure, and the same reference numerals denote the same elements throughout the specification.

[0039] In addition, in the drawings, the size and thickness of each element are arbitrarily shown for the convenience of description, and the present disclosure is not necessarily limited to the size and thickness shown in the drawings. In the drawings, the thickness of layers, regions, etc. are exaggerated for clarity. In the drawings, the thickness of some layers and regions are exaggerated for the convenience of description.

[0040] Furthermore, it should be understood that when an element, such as a layer, film, region, or plate, is referred to as being "on" or "above" another element, it can be directly on the other element or intervening elements may be present. Conversely, when an element is referred to as being "directly on" another element, this means that no intervening elements are present. Furthermore, the terms "on" or "above" refer to being positioned above or below a reference portion and do not necessarily mean being positioned at the upper end of the reference portion facing opposite to the force of gravity.

[0041] Further, throughout the specification, when a part is referred to as “including” a certain component, unless otherwise specified, it means that the part may further include other components, rather than excluding other components.

[0042] Furthermore, throughout the specification, when referred to as a “plane”, it means when the target portion is viewed from the upper side, 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.

[0043] Hereinafter, a battery module according to an embodiment of the present disclosure will be described. However, the description here is based on the front surface of the front and rear surfaces of the battery module, but is not necessarily limited thereto. Even in the case of the rear surface, the description can be given with the same or similar content.

[0044] Figure 4 is an exploded perspective view of a battery module according to an embodiment of the present disclosure. Figure 5 It shows the composition Figure 4 A perspective view of a state in which components of a battery module are assembled.

[0045] According to an embodiment of the present disclosure, the battery module 100 includes: a battery cell stack 120, in which a plurality of battery cells are stacked along a first direction (y-axis); a module frame 200, which accommodates the battery cell stack 120; and a first thermally conductive resin layer 310, which is located between the battery cell stack 120 and the lower portion of the module frame 200.

[0046] Furthermore, the battery module 100 further includes: bus bar frames 130 respectively located on the front and rear surfaces of the battery cell stack 120; and end plates 150 for covering the bus bar frames 130. Here, bus bars 141 and 145 ( Figure 7 ) may be provided in the busbar frame 130 .

[0047] refer to Figure 4 In the battery cell stack 120 housed in the module frame 200, a plurality of battery cells 110 are stacked along a first direction (y-axis direction), wherein the battery cells 110 are preferably pouch-type battery cells. The battery cells 110 can be manufactured by housing an electrode assembly in a pouch case comprising a laminate of resin and metal layers, and then heat-sealing the sealing portion of the pouch case. Such battery cells 110 can be composed of a plurality of cells, and the plurality of battery cells 110 form a battery cell stack 120 stacked and electrically connected to each other.

[0048] The module frame 200 includes a U-shaped frame 300 including a bottom surface and two side surfaces connected to the bottom surface, and an upper plate 400 for covering the upper portion of the battery cell stack 120 attached to the U-shaped frame 300. That is, the lower portion of the module frame 200 may be the U-shaped frame 300, and the upper portion of the module frame 200 may be the upper plate 400. However, the module frame 200 may be replaced with an L-shaped frame or a U-shaped frame, as well as frames of other shapes such as an upper plate, but is not limited thereto.

[0049] Further, a first thermally conductive resin layer 310 may be formed on the bottom surface of the lower portion of the module frame 200. In other words, the first thermally conductive resin layer 310 may be formed by applying thermally conductive resin to the bottom surface of the U-shaped frame 300.

[0050] In one example, the first thermally conductive resin layer 310 may be formed by attaching a heat transfer pad. In another example, the first thermally conductive resin layer 310 may be formed by applying a thermally conductive resin to the bottom surface of the U-shaped frame 300 before attaching the battery cell stack 120 to the bottom surface of the U-shaped frame 300. Then, as the thermally conductive resin cures, the first thermally conductive resin layer 310 may be formed.

[0051] Therefore, the first thermally conductive resin layer 310 may transfer heat generated in the battery cells 110 to the bottom of the battery module 100 , and may fix the battery cell stack 120 by the adhesive force possessed by the first thermally conductive resin layer 310 itself.

[0052] Next, the liquid injection hole 450 and the shielding pad 470 included in the second thermally conductive resin layer 160 and the upper plate 400 will be described in detail.

[0053] Figure 6 It shows Figure 4 A perspective view of a battery module in which the upper plate of the module frame is turned upside down. Figure 7 It shows Figure 4 Figure 1 shows a diagram of the busbar frame of a battery module. Figure 8 It is shown from Figure 4 A perspective view of a battery module with the upper portion of the module frame removed.

[0054] refer to Figure 6 In the battery module 100 according to the present embodiment, at least one liquid injection hole 450 for injecting thermally conductive resin may be formed in the upper portion of the module frame 200 . In other words, at least one liquid injection hole 450 may be formed in the upper plate 400 .

[0055] Here, the liquid injection hole 450 penetrates the upper plate 400 and may be a hole having a predetermined size. More specifically, the liquid injection hole 450 may be sized so that the thermally conductive resin is easily injected and relatively less external air flows therethrough.

[0056] In addition, a thermally conductive resin may be injected into the liquid injection hole 450. Here, the thermally conductive resin injected into the liquid injection hole 450 may be in the form of a resin or a slurry, but is not limited thereto. Then, as the thermally conductive resin solidifies, a second thermally conductive resin layer 160 may be formed. That is, the second thermally conductive resin layer 160 may be formed from the thermally conductive resin injected into at least one liquid injection hole 450. Here, the second thermally conductive resin layer 160 may be located between the battery cell stack 120 and the upper portion of the module frame 200. In other words, the second thermally conductive resin layer 160 may be located between the battery cell stack 120 and the upper plate 400.

[0057] Therefore, the battery module 100 according to the present embodiment can cool the upper surface of the battery pack 120 through the second thermally conductive resin layer 160 , thereby further improving cooling performance together with the first thermally conductive resin layer 310 .

[0058] Reference Figure 6 In the battery module 100 according to the present embodiment, at least one shielding pad 470 is located on the lower surface of the upper portion of the module frame 200. In other words, at least one shielding pad 470 is located on the lower surface of the upper plate 400. Here, the shielding pad 470 is open at its central portion and surrounds the liquid injection hole 450. Further, the shielding pad 470 may protrude in a direction corresponding to the direction (z-axis) toward the battery cell stack 120. Preferably, the shielding pad 470 protrudes in a direction corresponding to the direction (z-axis) toward the battery cell stack and may be in contact with the upper portion of the battery cell stack.

[0059] Here, the shielding pad 470 may include a material having high insulation properties. In one example, it may include at least one of polyethylene terephthalate (PET), polycarbonate (PC), polyimide (PI), and polyamide (PA). However, any material may be applied without limitation as long as the material can prevent the thermally conductive resin from overflowing and does not react with the thermally conductive resin injected into the injection hole 450.

[0060] Reference Figure 6 and Figure 8 , the second thermally conductive resin layer 160 may be surrounded by the shielding pad 470. In other words, the second thermally conductive resin layer 160 may be formed at a position corresponding to the central portion of the shielding pad 470.

[0061] Therefore, the shielding pad 470 can regulate the area where the second thermally conductive resin layer 160 is formed and prevent the thermally conductive resin injected into the liquid injection hole 450 from being injected into an unnecessary area. That is, the shielding pad 470 can prevent the thermally conductive resin injected into the liquid injection hole 450 from being applied to an area deviated from the shielding pad 470.

[0062] Furthermore, the shielding mat 470 limits the area where the thermally conductive resin is applied, eliminating the need for additional disassembly and assembly of the battery module 100, and allowing the thermally conductive resin to be evenly applied to the desired location. Furthermore, the shielding mat 470 can reduce the cost of injecting thermally conductive resin into areas where it is not needed.

[0063] Reference Figure 4 and Figure 7 In the battery module 100 according to an embodiment of the present disclosure, the first bus bar 141 is attached to the central portion of the bus bar frame 130, and the second bus bars 145 may be attached to both side portions of the bus bar frame 130, respectively. Here, the second bus bar 145 may be a terminal bus bar. Here, the second bus bar 145 may be exposed to the outside of the battery module 100 so that an external device or circuit can be electrically connected to the battery cells 110. In one example, the second bus bar 145 may be connected to an external bus bar that is capable of being connected to another battery module adjacent to the battery module including the second bus bar 145.

[0064] More specifically, the first and second bus bars 141 and 145 are electrically connected to the electrode leads of the battery cells 110, and may generate increased heat during the charging and discharging of the battery module 100. In particular, during rapid charging of the battery module 100, the externally exposed portions of the second bus bars 145 may exhibit relatively significant heat generation. However, the externally exposed portions of the second bus bars 145 are located away from the first thermally conductive resin layer 310, which may result in a problem in which direct cooling by the first thermally conductive resin layer 310 is not possible.

[0065] Here, reference Figures 6 to 8 , the liquid injection hole 450 and the shielding pad 470 may be located adjacent to one end rather than the center of the upper portion of the module frame 200. In other words, the liquid injection hole 450 and the shielding pad 470 may be located adjacent to one end rather than the center of the upper plate 400.

[0066] More specifically, the liquid injection hole 450 and the shielding pad 470 may be located at a corner of one end portion in the upper portion of the module frame 200. In other words, the liquid injection hole 450 and the shielding pad 470 may be located at a corner of one end portion of the upper plate 400. In other words, the liquid injection hole 450 and the shielding pad 470 may be located adjacent to the second bus bar 145, respectively.

[0067] In one example, the liquid injection hole 450 includes a first liquid injection hole and a second liquid injection hole, and the shielding pad 470 includes a first shielding pad and a second shielding pad. Here, the first liquid injection hole is surrounded by a first shielding pad, and the second liquid injection hole can be surrounded by a second shielding pad. In addition, the first liquid injection hole and the first shielding pad can be located at the corner of one side end in the upper portion of the module frame 200. In addition, the second liquid injection hole and the second shielding pad can be located at the corner of the other side end in the upper portion of the module frame 200. In other words, the first liquid injection hole and the first shielding pad are respectively located at positions adjacent to the second bus bar 145 attached to one side of the bus bar frame 130, and the second liquid injection hole and the second shielding pad can be respectively located at positions adjacent to the second bus bar 145 attached to the other side of the bus bar frame 130.

[0068] Therefore, unlike conventional battery modules 10, in the battery module 100 according to this embodiment, the second thermally conductive resin layer 160 can be formed adjacent to the portion of the second bus bar 145 located at the upper portion of the battery cell stack 120 where the most heat is generated. Specifically, it can have a structure that dissipates heat concentratedly to the portion adjacent to the second thermally conductive resin layer 160, thereby effectively reducing temperature deviations within the battery module 100. In particular, the second thermally conductive resin layer 160 can effectively suppress localized temperature increases that occur in the portion adjacent to the second bus bar 145 during fast charging.

[0069] Hereinafter, a heat transfer path inside the battery module 100 will be described in detail.

[0070] Figure 9 It is along Figure 5 Cross-sectional view of cutting line BB.

[0071] Reference Figure 5 and Figure 9 , the first thermally conductive resin layer 310 is in contact with the lower portion of the battery cell stack 120 included in the battery module 100, and one end of the upper portion of the battery cell stack 120 may have a structure in contact with the second thermally conductive resin layer 160. In particular, even in the upper portion of the battery cell stack 120, the end portion of the upper surface of the battery cell 110 adjacent to the portion to which the second bus bar 145 is attached and the second thermally conductive resin layer 160 may be in contact with each other.

[0072] Therefore, unlike the conventional battery module 10 , the battery module 100 has a structure that cools the upper and lower portions of the battery cell stack 120 , so that heat generated in the battery cell stack 120 can be transferred in the second cooling direction D2 toward the upper and lower portions.

[0073] In particular, as described above, second thermally conductive resin layer 160 is located adjacent to second bus bar 145. Thus, the upper and lower portions of the portion where second bus bar 145 is located can be effectively cooled by first thermally conductive resin layer 310 and second thermally conductive resin layer 160, effectively reducing temperature differences within battery module 100. Furthermore, by more effectively suppressing the localized temperature increase of second bus bar 145 during rapid charging, the output of the battery including battery cell 110 can be prevented from being initially restricted.

[0074] On the other hand, one or more battery modules according to the present embodiment may be enclosed in a pack case to form a battery pack.

[0075] The battery module and the battery pack including the battery module can be applied to various devices. Such devices can be applied to vehicle devices such as electric bicycles, electric vehicles, or hybrid vehicles, but the present invention is not limited thereto and can be applied to various devices that can use battery modules, which also fall within the scope of the present disclosure.

[0076] Although the present invention has been shown and described above with reference to preferred embodiments, the scope of the present disclosure is not limited thereto, and those skilled in the art may use the principles of the invention as described in the appended claims to devise numerous other variations and modifications that will fall within the spirit and scope of the present disclosure.

[0077] [Explanation of Reference Signs]

[0078] 100: Battery module

[0079] 110: Battery cell

[0080] 120: Battery cell stack

[0081] 130: Busbar frame

[0082] 141: First bus

[0083] 145: Second busbar

[0084] 150: End plate

[0085] 300: U-shaped frame

[0086] 400: On the board

Claims

1. A battery module comprising: a battery cell stack in which a plurality of battery cells are stacked along a first direction; a module frame for accommodating the battery cell stack; a first thermally conductive resin layer positioned between the battery cell stack and a lower portion of the module frame; as well as a second thermally conductive resin layer located between the battery cell stack and an upper portion of the module frame, wherein at least one liquid injection hole for injecting thermally conductive resin is formed on the upper portion of the module frame, wherein at least one shielding pad is located on the lower surface of the upper portion of the module frame, and wherein the central portion of the shielding pad is open and the shielding pad surrounds the liquid injection hole, The liquid injection hole and the shielding pad are located at positions closer to one end portion than to a central portion of the upper portion of the module frame.

2. The battery module according to claim 1, wherein: The second thermally conductive resin layer is formed of the thermally conductive resin injected into the at least one liquid injection hole.

3. The battery module according to claim 2, wherein: The second thermally conductive resin layer is surrounded by the shielding pad.

4. The battery module according to claim 1, wherein: The liquid injection hole and the shielding pad are located at a corner of one side end portion at the upper portion of the module frame.

5. The battery module according to claim 1 , further comprising bus bar frames respectively located on the front and rear surfaces of the battery cell stack, and end plates covering the bus bar frames, in, A first bus bar is attached to a central portion of the bus bar frame, and Second bus bars are respectively attached to both side portions of the bus bar frame.

6. The battery module according to claim 5, wherein: The second bus bar is a terminal bus bar.

7. The battery module according to claim 5, wherein: The liquid injection hole and the shielding pad are respectively located adjacent to the second bus bar.

8. The battery module according to claim 1, wherein: The module frame includes: a U-shaped frame including a bottom surface and two side surfaces connected to both sides of the bottom surface; and an upper plate for covering the battery cell stack attached to the U-shaped frame. The upper portion of the module frame is the upper plate.

9. The battery module according to claim 2, wherein: The first thermally conductive resin layer is formed by applying a thermally conductive resin to the bottom surface of the U-shaped frame or attaching a heat transfer pad. 10 . A battery pack comprising the battery module according to claim 1 .

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