Battery module

Abstract

The invention provides a battery module. The battery module comprises a plurality of battery cells; a bus bar electrically connecting the plurality of battery cells; a holder on the plurality of battery cells and accommodating the bus bar; and a cover portion on the holder and covering the bus bar, in which the cover portion includes a first layer, a second layer on the first layer, and a third layer on the second layer, and the second layer includes a material different from materials of the first layer and the third layer.

Description

Technical Field

[0001] This disclosure relates to a battery module. Background Technology

[0002] Unlike primary batteries, which are non-rechargeable, secondary batteries are rechargeable and dischargeable. Low-capacity battery cells are already used in small portable electronic devices (such as smartphones, feature phones, laptops, digital cameras, and camcorders), while high-capacity battery cells are widely used as power sources for motors in hybrid vehicles, electric vehicles, etc., and as batteries for energy storage. A battery cell includes an electrode assembly containing positive and negative electrodes, a housing that houses the electrode assembly, and electrode terminals connected to the electrode assembly.

[0003] On the other hand, large-capacity battery cells can be used as battery modules in which a large number of battery cells are connected in series and / or in parallel to provide high energy density (e.g., for driving motors in hybrid vehicles). Summary of the Invention

[0004] The embodiments of this disclosure provide a battery module with improved stability.

[0005] However, the technical problems to be solved by this disclosure are not limited to those described herein, and those skilled in the art can clearly understand other problems not mentioned from the description of the disclosure herein.

[0006] According to the disclosed aspects, a battery module is provided, the battery module comprising: a plurality of battery cells; a busbar electrically connected to the plurality of battery cells; a retainer located on the plurality of battery cells and housing the busbar; and a cover located on the retainer and covering the busbar, wherein the cover comprises a first layer, a second layer located on the first layer and a third layer located on the second layer, and the second layer comprises a material different from the materials of the first layer and the third layer.

[0007] The first and third layers may include at least one of mica, ceramic fiber, glass fiber, and silica fiber.

[0008] The second layer may include at least one of aerogel, polyurethane foam, and phenolic foam.

[0009] At least one of aerogel, polyurethane foam and phenolic foam may be included in the second layer in an amount of 60% to 90% by weight.

[0010] The battery module may also include a cover that covers the upper part, wherein the cover is attached to the upper cover.

[0011] The upper surface of the manifold can be spaced a certain distance from the lower surface of the cover.

[0012] The cover may also include protrusions that are positioned to protrude toward multiple battery cells.

[0013] Each of the protrusions can be located between adjacent busbars within the busbar.

[0014] The length of the protrusion can be 2mm to 4mm.

[0015] The thickness of the first and third layers can be from 0.1 mm to 0.3 mm, and the thickness of the second layer can be from 0.5 mm to 2 mm.

[0016] According to another aspect of the disclosure, a battery module is provided, the battery module comprising: a plurality of battery cells; a busbar electrically connected to the plurality of battery cells; and a cover covering the busbar, wherein the cover includes a first layer, a second layer on the first layer and a third layer on the second layer, and the cover includes a protrusion positioned to protrude toward the plurality of battery cells and located between the busbar.

[0017] The raised lower surface can be positioned below the upper surface of the busbar.

[0018] The length of each of the protrusions can be 2mm to 4mm.

[0019] The protrusion may include at least one of flame-retardant silicone resin, ethylene propylene diene monomer (EPDM), fluorosilicone resin, polytetrafluoroethylene (PTFE), para-aramid fiber, fluororubber (FKM), polyvinyl chloride (PVC), and polyurethane.

[0020] The thickness of the first and third layers is 0.1 mm to 0.3 mm, and the thickness of the second layer can be 0.5 mm to 2 mm.

[0021] The first and third layers include at least one of mica, ceramic fiber, glass fiber, and silica fiber.

[0022] The second layer may include at least one of aerogel, polyurethane foam, and phenolic foam.

[0023] At least one of aerogel, polyurethane foam and phenolic foam may be included in the second layer in an amount of 60% to 90% by weight.

[0024] The width of each in the cover can be greater than the width of each in the busbar.

[0025] The upper surface of each of the manifolds can be spaced apart from the lower surface of the cover by a certain distance, and the distance between the upper surface of each of the manifolds and the lower surface of the cover can be from 0.1 mm to 5 mm. Attached Figure Description

[0026] The following figures accompanying the specification illustrate embodiments of the present disclosure to facilitate an understanding of the technical concept of the disclosure in conjunction with the detailed description thereof, and therefore the disclosure should not be construed as limited to the matters shown in the figures.

[0027] Figure 1 This is an exploded perspective view schematically illustrating an example of a battery module according to an embodiment of the present disclosure.

[0028] Figure 2 It is shown schematically. Figure 1 A perspective view of an example battery cell in a battery module.

[0029] Figure 3 It is schematically shown along Figure 2 An example sectional view of the section cut by line III-III'.

[0030] Figure 4 It is shown schematically. Figure 1 A cross-sectional view of an example of the arrangement of the cover and busbars of a battery module.

[0031] Figure 5 It is shown schematically. Figure 1 A cross-sectional view of an example of the cover of a battery module.

[0032] Figure 6 It is shown schematically. Figure 1 A cross-sectional view of another example of the arrangement of the cover and busbars of the battery module. Detailed Implementation

[0033] Figure 1 This is an exploded perspective view schematically illustrating an example of a battery module according to an embodiment of the present disclosure.

[0034] Reference Figure 1 According to embodiments of the present disclosure, a battery module 100 may include: a plurality of battery cells 10 arranged in a direction X; and a busbar 120 that electrically connects one of the plurality of battery cells 10 to another battery cell adjacent to it in the plurality of battery cells 10.

[0035] Each of the battery cells 10 may include a first terminal 11 and a second terminal 12 electrically connected via a busbar 120 on one side, and an exhaust port 13 for discharging gas generated inside the battery cell 10.

[0036] The first terminal 11 can be either a positive terminal or a negative terminal. If the first terminal 11 is a positive terminal, then the second terminal 12 can be a negative terminal, and conversely, if the first terminal 11 is a negative terminal, then the second terminal 12 can be a positive terminal. That is, the first terminal 11 and the second terminal 12 are formed to have different polarities, and are not limited to any particular polarity.

[0037] A first terminal 11 of a battery cell 10 can be electrically connected to a second terminal 12 of another adjacent battery cell 10 via a busbar 120, and a second terminal 12 of a battery cell 10 can be electrically connected to a first terminal 11 of another adjacent battery cell 10 via another busbar 120. On the other hand, although Figure 1 A series connection is shown, but this disclosure is not limited to this structure; of course, various connection structures can be used as needed. Furthermore, the number and arrangement of the battery cells 10 are not limited to this. Figure 1 The structure shown can be modified as needed.

[0038] On the other hand, the arranged battery cells 10 can be housed in a housing. The housing may include: a pair of end plates 61, 62 facing the large surface of the battery cell 10; a side plate 63 connected to the pair of end plates 61, 62; and a bottom plate (not shown).

[0039] Side plate 63 can support the side surface of battery cell 10, and bottom plate (not shown) can support the bottom surface of battery cell 10. In addition, a pair of end plates 61, 62, side plate 63 and bottom plate can be joined by means of components such as bolts, but not limited thereto, and any method that can be used for fastening can be used.

[0040] On the other hand, the battery module 100 may also include a retainer 110 located on the battery cell 10 and accommodating the busbar 120, a cover 130 located on the retainer 110 and covering the busbar 120, and an upper cover 150 coupled to the housing to accommodate the battery cell 10, the retainer 110 and the cover 130.

[0041] The housing can be attached to the top cover 150 using fastening components such as bolts, but is not limited to this, and any method that can be used for fastening can be used. That is, the housing can be attached to the top cover 150 to form an internal space, and the battery cell 10, the retainer 110 and the cover 130 can be accommodated in the internal space.

[0042] Therefore, the inventors have recognized that it is advantageous for the casing and top cover 150 to be made of materials that can protect the battery cell 10, the retainer 110, and the cover 130 from mechanical or thermal shock. The materials of the casing and top cover 150 may include, but are not limited to, at least one of acrylonitrile butadiene styrene (ABS), polycarbonate (PC), polypropylene (PP), aluminum, and stainless steel.

[0043] On the other hand, the retainer 110 may be located on the battery cell 10 and accommodate the busbar 120. Additionally, the retainer 110 may include sensing units that perform various protection functions to improve the stability and lifespan of the battery module 100. For example, the sensing units may be connected to the battery management system (BMS).

[0044] Each of the busbars 120 may be equipped with a terminal for temperature measurement and / or a terminal for voltage measurement. The measured information can be transmitted to the sensing unit via wiring and managed in an integrated manner.

[0045] On the other hand, each of the plurality of battery cells 10 may include an exhaust port 13 at its top as a gas exhaust passage, and the retainer 110 may also include a hole 113 superimposed on the exhaust port 13. The hole 113 may be an exhaust passage for high-temperature gas released when the temperature of the battery cell 10 rises and high-temperature gas is released through the exhaust port 13.

[0046] On the other hand, the cover 130 can be located on the retainer 110 and can cover the busbar 120. For example... Figure 1 As shown, the cover 130 can cover the spaced-apart busbars 120 as a whole.

[0047] When the battery module 100 includes a cover 130, the cover 130 can protect the busbar 120 from mechanical impact and prevent the busbar 120 from short-circuiting, thereby improving the stability of the battery module.

[0048] More specifically, when the battery module 100 experiences thermal runaway, foreign objects may be present inside the battery module 100. For example, the foreign object may be fragments of a damaged battery cell 10, and the fragments may be conductive material included in the battery cell 10. Additionally, the cover 150 may be damaged during thermal runaway, and fragments of the cover 150 may also include conductive material. In the event of thermal runaway of the battery module 100, the cover 130 may cover the busbar 120 to prevent the busbar 120 from contacting the fragments described herein, thereby preventing the busbar 120 from short-circuiting and causing additional secondary thermal runaway.

[0049] On the other hand, the cover 130 may include a plurality of cover portions 130a, 130b spaced apart from each other. The hole 113 of the retainer 110 may be exposed between the spaced-apart cover portions 130a, 130b. When the cover portions 130a, 130b expose the hole 113, a channel for venting high-temperature gases can be formed when the temperature of the battery cell 10 rises and high-temperature gases are discharged to the vent hole 13, thereby improving the stability of the battery module 100. Figure 1 In the diagram, the cover 130 is shown as two covers 130a and 130b, but the number of covers 130 is not limited to two and can be changed as needed.

[0050] Figure 2 It is shown schematically. Figure 1 A perspective view of an example of a battery cell 10 of a battery module 100, and Figure 3 It is schematically shown along Figure 2 An example sectional view of the section cut by line III-III'.

[0051] Refer to together Figure 2 and Figure 3 According to this embodiment, the battery cell 10 may include a housing 15 and at least one electrode assembly 210. The at least one electrode assembly 210 is formed by winding a positive electrode 211 and a negative electrode 212 together with a separator 213 that serves as an insulator therebetween. The electrode assembly 210 is housed in the housing 15.

[0052] The battery cell 10 according to this embodiment is described as a prismatic lithium-ion battery cell as an example. However, this disclosure is not limited thereto, and this disclosure can be applied to various types of battery cells (such as lithium polymer battery cells or cylindrical battery cells).

[0053] The positive electrode 211 and the negative electrode 212 may include a coated portion and an uncoated portion 211a of the positive electrode and an uncoated portion 212a of the negative electrode. The coated portion is the area in which an active material is applied to a current collector formed by a metal foil of a thin plate, and the uncoated portions 211a of the positive electrode and 212a of the negative electrode are the areas in which no active material is applied.

[0054] Positive electrode 211 and negative electrode 212 are wound together, and a diaphragm 213, which serves as an insulator, is located between positive electrode 211 and negative electrode 212. However, this disclosure is not limited thereto, and the electrode assembly 210 described herein may have a structure in which positive and negative electrodes formed of a plurality of sheets are alternately stacked and a diaphragm is located between the positive and negative electrodes.

[0055] The housing 15 forms the overall appearance of the battery cell 10 and may include a conductive metal (such as aluminum, aluminum alloy, or nickel-plated steel). Additionally, the housing 15 can provide space for accommodating the electrode assembly 210.

[0056] The battery cell 10 may include a cover 17 that covers an opening in the housing 15, and the housing 15 and the cover 17 may include conductive materials. Here, the first terminal 11 electrically connected to the positive electrode 211 and the second terminal 12 electrically connected to the negative electrode 212 may be mounted to protrude outwards through the cover 17.

[0057] In addition, the outer peripheral surfaces of the upper posts of the first terminal 11 and the second terminal 12 protruding outward from the cover plate 17 may be threaded and fixed to the cover plate 17 with nuts.

[0058] However, this disclosure is not limited thereto, and the first terminal 11 and the second terminal 12 may be formed by a rivet structure and may be riveted or welded to the cover plate 17.

[0059] Additionally, the cover plate 17 can be formed from a thin plate and can be attached to the opening of the housing 15. An electrolyte injection port 14, into which a sealing plug can be installed, can be formed in the cover plate 17, and a vent hole 13 with a notch can be installed in the cover plate 17.

[0060] The first terminal 11 and the second terminal 12 can be electrically connected to the current collector, which includes a first current collector 240 welded to the uncoated positive electrode portion 211a and a second current collector 250 welded to the uncoated negative electrode portion 212a (hereinafter referred to as the positive current collector and the negative current collector, respectively).

[0061] For example, the first terminal 11 and the second terminal 12 can be soldered to the positive current collector 240 and the negative current collector 250, respectively. However, this disclosure is not limited thereto; the first terminal 11 and the positive current collector 240 can be integrally formed, and the second terminal 12 and the negative current collector 250 can be integrally formed.

[0062] Additionally, an insulating member formed of insulating material can be installed between the electrode assembly 210 and the cover plate 17. Here, the insulating member may include a first lower insulating member 260 and a second lower insulating member 270, and each of the first lower insulating member 260 and the second lower insulating member 270 may be installed between the electrode assembly 210 and the cover plate 17.

[0063] Additionally, according to this embodiment, one end of a separator member that can be mounted to face one surface of the electrode assembly 210 can be mounted between the insulating member and the first terminal 11 and the second terminal 12.

[0064] Here, the separating member may include a first separating member 280 and a second separating member 290.

[0065] Therefore, one end of each of the first partition member 280 and the second partition member 290, which can be mounted to face one surface of the electrode assembly 210, can be mounted between the first lower insulating member 260 and the first terminal 11 or between the second lower insulating member 270 and the second terminal 12.

[0066] Finally, the first terminal 11 soldered to the positive current collector 240 and the second terminal 12 soldered to the negative current collector 250 can be coupled to one end of each of the first lower insulating member 260 and the second lower insulating member 270, as well as the first separating member 280 and the second separating member 290.

[0067] Figure 4 It is shown schematically. Figure 1 A cross-sectional view of an example arrangement of the cover 130 and busbar 120 of the battery module 100, and Figure 5 It is shown schematically. Figure 1 A cross-sectional view of an example of the cover 130 of the battery module 100.

[0068] and Figure 1 Refer to together Figure 4 and Figure 5 The cover portion 130 may include a material with excellent insulating properties. Specifically, the cover portion 130 may include a first layer 131, a second layer 132, and a third layer 133, wherein the first layer 131 includes a material with excellent insulating properties, the second layer 132 is located on the first layer 131, and the third layer 133 is located on the second layer 132.

[0069] The first layer 131 and the third layer 133 of the cover 130 may comprise the same material, and the second layer 132 may comprise a material different from that of the first layer 131 and the third layer 133. Specifically, the first layer 131 and the third layer 133 may comprise at least one of mica, ceramic fiber, glass fiber, and silica fiber, and the second layer 132 may comprise at least one of aerogel, polyurethane foam, and phenolic foam.

[0070] On the other hand, if thermal runaway occurs in the battery module 100, foreign objects may be present inside the battery module 100. For example, the foreign object may be fragments of a damaged battery cell 10, and the fragments may be conductive materials included in the battery cell 10. Additionally, the cover 150 may be damaged during thermal runaway, and the fragments of the cover 150 may also include conductive materials. Such fragments may be at high temperatures.

[0071] The first layer 131 of the cover 130 is positioned adjacent to the busbar 120, and the third layer 133 is positioned adjacent to the top cover 150. Therefore, the first layer 131 and the third layer 133 can be exposed first to the thermal conductive debris generated during thermal runaway of the battery module 100.

[0072] Mica, ceramic fiber, glass fiber, and silica fiber are materials with excellent electrical insulation, durability, and low thermal conductivity. Therefore, when the first layer 131 and the third layer 133 include at least one of mica, ceramic fiber, glass fiber, and silica fiber, the excellent insulation properties prevent conductive fragments and the busbar 120 from contacting each other and causing a short circuit. Furthermore, the excellent durability increases the mechanical strength of the cover 130, thereby preventing damage to the cover 130. Additionally, the low thermal conductivity prevents the heat energy of hot fragments from dissipating into the surrounding environment.

[0073] Aerogel, polyurethane foam, and phenolic foam are materials with excellent thermal insulation properties. Therefore, when the second layer 132 located between the first layer 131 and the third layer 133 of the cover 130 includes at least one of aerogel, polyurethane foam, and phenolic foam, thermal diffusion to the surrounding environment during thermal runaway of the battery module can be effectively prevented.

[0074] In other words, when the cover 130 is formed to include multiple layers, such that the first layer 131 and the third layer, which may come into contact with debris generated during thermal runaway, include at least one of mica, ceramic fiber, glass fiber, and silica fiber with excellent electrical insulation, durability, and thermal insulation properties, and the second layer 132 located between the first layer 131 and the third layer 133 includes at least one of aerogel, polyurethane foam, and phenolic foam with excellent thermal insulation properties, it can prevent conductive debris and busbar 120 from coming into contact with each other and causing a short circuit, and can effectively prevent the thermal energy of hot debris from being transferred to the surrounding environment, thereby improving the stability of the battery module 100.

[0075] On the other hand, at least one of aerogel, polyurethane foam, and phenolic foam in the second layer 132 of the cover 130 may be included in the second layer at a concentration of 60 wt% to 90 wt%. If at least one of aerogel, polyurethane foam, and phenolic foam is included in the second layer at a concentration of less than 60 wt%, there is a concern that the thermal insulation performance of the cover 130 may be reduced, and if at least one of aerogel, polyurethane foam, and phenolic foam is included in the second layer at a concentration of more than 90 wt%, there is a concern that material may be wasted.

[0076] On the other hand, mica, ceramic fibers, glass fibers, and silica fibers, which can be included in the first layer 131 and the third layer 133, can exhibit excellent insulation properties and physical durability even when used in thin layers. Conversely, although aerogel, polyurethane foam, and phenolic foam, which can be included in the second layer 132, are more brittle than mica, ceramic fibers, glass fibers, and silica fibers, they can exhibit excellent thermal insulation properties. Therefore, in order to maximize the thermal insulation properties and durability of the cover 130 within a defined thickness range, the thickness of the second layer 132 can be greater than the thicknesses of the first layer 131 and the third layer 133.

[0077] Therefore, the thickness h2 of the first layer 131 and the thickness h1 of the third layer 133 of the cover portion 130 can be from 0.1 mm to 0.3 mm. In addition, the thickness h3 of the second layer of the cover portion 130 can be from 0.5 mm to 2 mm.

[0078] If the thickness of the first layer 131 and the third layer 133 is less than 0.1 mm and the thickness of the second layer 132 is less than 0.5 mm, there are concerns that the durability, insulation and thermal insulation performance of the cover 130 may be reduced. If the thickness of the first layer 131 and the third layer 133 is greater than 0.3 mm and the thickness of the second layer 132 is greater than 2 mm, the cover 130 may become too thick, which may reduce space efficiency and lead to material waste.

[0079] On the other hand, even if the cover 130 has excellent electrical insulation, it may deteriorate, absorb moisture, or become contaminated if used for a long period of time, creating a path through which current may flow. In this case, the cover 130 may come into electrical contact with the busbar 120, causing a short circuit and fire.

[0080] Therefore, the cover 130 can be provided separately from the busbar 120. Therefore, the cover 130 can be attached to the upper cover 150, and the distance d between the upper surface of the busbar 120 and the lower surface of the cover 130 can be 0.1 mm to 5 mm.

[0081] If the distance d between the upper surface of the busbar 120 and the lower surface of the cover 130 is less than 0.1 mm, current may flow through the cover 130 due to deterioration, moisture absorption, or contamination. Furthermore, if mechanical impact or similar forces are applied to the battery module 100, the distance d between the upper surface of the busbar 120 and the lower surface of the cover 130 may shorten, potentially causing the busbar 120 to contact the cover 130 and trigger a short circuit. Additionally, if the distance d between the upper surface of the busbar 120 and the lower surface of the cover 130 exceeds 5 mm, the integration density of the battery module 100 may decrease.

[0082] On the other hand, since the manifold 120 is spaced apart from the cover 130, an air layer including air can be formed in the space between the manifold 120 and the cover 130.

[0083] Because air has low thermal conductivity and low electrical conductivity, air layers can provide excellent thermal insulation and electrical insulation effects. For example, the thermal conductivity of air at room temperature is 0.024 W / (m·K), and the electrical conductivity of air is 10⁻⁶ W / (m·K). -14 (S / m). Therefore, when the battery module 100 includes an air layer, heat transfer can be prevented more effectively if thermal runaway of the battery module 100 occurs.

[0084] Additionally, as described herein, the cover 130 may deteriorate, absorb moisture, or become contaminated, creating a channel through which current can flow. However, because the air layer is an excellent electrical insulator, it prevents current from the busbar 120 from flowing to the cover 130, thereby improving the stability of the battery module 100.

[0085] As described herein, if thermal runaway occurs in battery module 100, foreign objects may be generated inside battery module 100. For example, the foreign object may be fragments of a damaged battery cell 10, and the fragments may be high-temperature conductive materials included in the battery cell 10. Additionally, the cover 150 may be damaged during thermal runaway, and fragments of the cover 150 may also include high-temperature conductive materials.

[0086] Because the cover 130 is configured to protect the busbar 120 from the aforementioned debris, the width W1 of the cover 130 can be greater than the width W2 of the busbar 120. Here, the width W1 of the cover 130 and the width W2 of the busbar 120 refer to the lengths measured in the direction Y, which is perpendicular to the arrangement direction X of the battery cells.

[0087] If the width W1 of the cover 130 is less than or equal to the width W2 of the busbar 120, the cover 130 may not be able to properly cover the busbar 120, and there is a concern that the aforementioned debris may come into contact with the busbar 120, causing a short circuit and additional thermal runaway.

[0088] Figure 6 It is shown schematically. Figure 1 A cross-sectional view of another example of the arrangement of the cover 630 and busbar 620 of the battery module.

[0089] and Figure 1 Refer to together Figure 6According to another embodiment of the present disclosure, the battery module 100 may include a retainer 110 located on the battery cell 10 and accommodating the busbar 620, a cover 630 located on the retainer 110 and covering the busbar 620, and an upper cover 150 coupled to the housing to accommodate the battery cell 10, the retainer 110 and the cover 630.

[0090] The cover 630 may include a first layer 631, a second layer 632 and a third layer 633, wherein the first layer 631 includes a material with excellent insulating properties, the second layer 632 is located on the first layer 631 and the third layer 633 is located on the second layer 632.

[0091] Additionally, the first layer 631 and the third layer 633 of the cover 630 may comprise the same material, while the second layer 632 may comprise a material different from that of the first layer 631 and the third layer 633. Specifically, the first layer 631 and the third layer 633 may comprise at least one of mica, ceramic fiber, glass fiber, and silica fiber, while the second layer 632 may comprise at least one of aerogel, polyurethane foam, and phenolic foam.

[0092] The cover 630 may also include a protrusion 635 projecting toward the battery cell 10. The protrusion 635 may be located individually between any two adjacent busbars 620. That is, the lower surface of the protrusion 635 may be lower than the upper surface of the busbar 620.

[0093] The protrusions 635 are located between the busbars 620 and therefore need to be formed of a durable, heat-resistant, insulating, and flexible material. Therefore, the protrusions 635 may include at least one of flame-retardant silicone resin, ethylene propylene diene monomer (EPDM), fluorosilicone resin, polytetrafluoroethylene (PTFE), para-aramid fiber, fluororubber (FKM), polyvinyl chloride (PVC), and polyurethane.

[0094] When the protrusion 635 is placed between the busbars 620, the busbars 620 can be fixed in place if they move within the battery module 100 due to external impacts or the like. Therefore, breakage of the welded area between the busbars 620 and the battery cell 10 can be prevented.

[0095] On the other hand, if thermal runaway occurs in the battery module 100, foreign objects may appear inside the battery module 100. For example, the foreign object may be fragments of a damaged battery cell 10, and the fragments may be high-temperature conductive materials included in the battery cell 10. In addition, the top cover 150 may be damaged during thermal runaway, and the fragments of the top cover 150 may also include high-temperature conductive materials.

[0096] When the cover 630 includes a protrusion 635 protruding toward the battery cell 10 and the protrusion 635 is located individually between any two adjacent busbars 620, the protrusion 635 can protect the side surface of the busbars 620 in the event of thermal runaway of the battery module 100, thereby preventing the aforementioned debris from contacting the busbars 620 and causing a short circuit, and preventing heat transfer between the busbars 620, thereby improving the stability of the battery module 100.

[0097] On the other hand, the cover 630 can be positioned separately from the manifold 620. Therefore, an air layer 640, including air, can be formed in the space between the manifold 620 and the cover 630.

[0098] When the battery module 100 includes an air layer 640, the degree of heat transfer and additional heating caused in the event of thermal runaway of the battery module 100 can be reduced. Additionally, as described herein, the cover 630 may deteriorate, absorb moisture, or become contaminated, creating pathways through which current could flow. However, because the air layer 640 is an excellent electrical insulator, it prevents current from the busbar 620 from flowing to the cover 630.

[0099] On the other hand, the length H of the protrusion 635 can be between 2 mm and 4 mm. Because the cover 630 is positioned separately from the busbar 620, if the length H of the protrusion 635 is less than 2 mm, the protrusion 635 may be too short to adequately cover the side surface of the busbar 620. Additionally, if the length H of the protrusion 635 exceeds 4 mm, the protrusion 635 may become excessively long, potentially leading to material waste.

[0100] On the other hand, Figure 6 In the diagram, protrusion 635 is shown protruding to the lower surface of busbar 620, but is not limited thereto; protrusion 635 can have any shape, as long as the lower surface of protrusion 635 is positioned below the upper surface of busbar 620. Additionally, in Figure 6 In the present embodiment, when the protrusion 635 is located between the busbars 620, there is no empty space between the protrusion 635 and the busbars 620. However, in some embodiments, there may be an empty space between the protrusion 635 and the busbars 620.

[0101] Although this disclosure has been described herein with reference to limited embodiments and accompanying drawings, it is not limited thereto, and it will be apparent to those skilled in the art that various modifications and variations can be made within the scope of this disclosure and within the equivalents of the claims described herein.

[0102] According to embodiments of this disclosure, because the battery module includes a cover that covers the busbar, it can prevent the busbar from coming into contact with foreign objects present inside the battery module due to thermal runaway or the like, or from coming into contact with fragments generated when the cover is damaged due to thermal runaway or the like, thereby preventing short circuits and improving the stability of the battery module.

[0103] However, the effects that can be obtained through this disclosure are not limited to those described herein, and those skilled in the art will clearly understand from the description of the disclosure herein that other technical effects are not mentioned.

Claims

1. A battery module, the battery module comprising: Multiple battery cells; The busbar electrically connects the multiple battery cells; A retainer is located on the plurality of battery cells and accommodates the busbar; as well as The cover portion, located on the retainer and covering the busbar, The cover includes a first layer, a second layer located on the first layer, and a third layer located on the second layer. The second layer comprises a material different from that of the first and third layers.

2. The battery module according to claim 1, wherein, Both the first layer and the third layer include at least one of mica, ceramic fiber, glass fiber and silica fiber.

3. The battery module according to claim 1, wherein, The second layer includes at least one of aerogel, polyurethane foam and phenolic foam.

4. The battery module according to claim 3, wherein, At least one of the aerogel, the polyurethane foam, and the phenolic foam is included in the second layer in an amount of 60% to 90% by weight.

5. The battery module according to claim 1, wherein, The battery module also includes: The upper cover covers the lid portion; and The cover portion is attached to the upper cover.

6. The battery module according to claim 1, wherein, The upper surface of the manifold is spaced apart from the lower surface of the cover.

7. The battery module according to claim 1, wherein, The cover also includes a protrusion positioned to protrude toward the plurality of battery cells.

8. The battery module according to claim 7, wherein, Each of the protrusions is located between adjacent busbars within the busbar.

9. The battery module according to claim 7, wherein, Each of the protrusions has a length of 2mm to 4mm.

10. The battery module according to claim 1, wherein: The thickness of the first layer and the third layer is each between 0.1 mm and 0.3 mm; and The thickness of the second layer is 0.5 mm to 2 mm.

11. A battery module, the battery module comprising: Multiple battery cells; The busbar electrically connects the multiple battery cells; as well as Cover, covering the busbar, The cover includes a first layer, a second layer located on the first layer, and a third layer located on the second layer. The cover includes a protrusion positioned to protrude toward the plurality of battery cells and located between the busbars.

12. The battery module according to claim 11, wherein, The lower surface of each of the protrusions is positioned below the upper surface of the busbar.

13. The battery module according to claim 11, wherein, Each of the protrusions has a length of 2mm to 4mm.

14. The battery module according to claim 11, wherein, The protrusions include at least one of flame-retardant silicone resin, ethylene propylene diene monomer, fluorosilicone resin, polytetrafluoroethylene, para-aramid fiber, fluororubber, polyvinyl chloride, and polyurethane.

15. The battery module according to claim 11, wherein: The thickness of the first layer and the third layer is each between 0.1 mm and 0.3 mm; and The thickness of the second layer is 0.5 mm to 2 mm.

16. The battery module according to claim 11, wherein, Both the first layer and the third layer include at least one of mica, ceramic fiber, glass fiber and silica fiber.

17. The battery module according to claim 11, wherein, The second layer includes at least one of aerogel, polyurethane foam and phenolic foam.

18. The battery module according to claim 17, wherein, At least one of the aerogel, the polyurethane foam, and the phenolic foam is included in the second layer in an amount of 60% to 90% by weight.

19. The battery module according to claim 11, wherein, The width of each of the covers is greater than the width of each of the busbars.

20. The battery module according to claim 11, wherein: The upper surface of each of the manifolds is spaced apart from the lower surface of the cover; and The distance between the upper surface of each of the manifolds and the lower surface of the cover is 0.1 mm to 5 mm.

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