Battery module

Abstract

There is provided a battery module including: a plurality of battery cells arranged side by side in a first direction and having main surfaces facing each other, each battery cell including a lower exhaust port; a thermal insulation layer covering the lower exhaust ports of the plurality of battery cells; and a lower sheet under the thermal insulation layer, where the lower sheet includes a first adhesive layer attached to the thermal insulation layer and a second adhesive layer on each of opposite sides of the first adhesive layer and attached to a lower surface of the plurality of battery cells, where the second adhesive layer is spaced apart from the first adhesive layer.

Description

[0001] This application claims priority and benefit to Korean Patent Application No. 10-2024-0139363, filed on October 14, 2024, with the Korean Intellectual Property Office, the entire disclosure of which is incorporated herein by reference. Technical Field

[0002] This disclosure relates to a battery module. Background Technology

[0003] Unlike primary batteries, which cannot be recharged, secondary batteries are batteries that can be repeatedly charged and discharged. Low-capacity batteries can be used in small, portable electronic devices such as smartphones, feature phones, laptops, digital cameras, and camcorders, while high-capacity batteries are widely used as power sources for motor drives in hybrid vehicles, electric vehicles, and as energy storage batteries. These batteries may include electrode assemblies containing positive and negative electrodes, a housing for accommodating the electrode assemblies, and electrode terminals connected to the electrode assemblies.

[0004] The information disclosed in the background section of this invention is intended only to enhance the understanding of the background of this disclosure, and therefore may include information that does not constitute conventional technology. Summary of the Invention

[0005] The embodiment provides a battery module with improved stability.

[0006] However, the problems to be solved by this disclosure are not limited to those mentioned above, and other problems and advantages not mentioned in this disclosure can be understood from the following description and will become clearer through embodiments of this disclosure. In some embodiments, it will be understood that the problems and advantages to be solved by this disclosure can be achieved by the means set forth in the claims and combinations thereof.

[0007] The battery module according to aspects of this disclosure includes: a plurality of battery cells arranged side by side along a first direction with their main surfaces facing each other, each battery cell including a lower vent; a heat insulation layer covering the lower vents of the plurality of battery cells; and a lower sheet located at the bottom of the heat insulation layer, wherein the lower sheet includes a first adhesive layer attached to the heat insulation layer and a second adhesive layer located on each of opposite sides of the first adhesive layer and attached to the lower surfaces of the plurality of battery cells, wherein the second adhesive layer may be spaced apart from the first adhesive layer.

[0008] In one embodiment, the insulation layer may extend in a direction substantially parallel to the first direction.

[0009] In an embodiment, the width of the insulation layer along a second direction perpendicular to the first direction may be greater than the width of the lower exhaust port along the second direction.

[0010] In one embodiment, the first adhesive layer may be thinner than the second adhesive layer.

[0011] In this embodiment, the thickness of the first adhesive layer can be from 0.01 mm to 0.03 mm.

[0012] In this embodiment, the thickness of the second adhesive layer can be from 0.3 mm to 0.7 mm.

[0013] In one embodiment, the insulation layer may include air foam.

[0014] In this embodiment, the air foam may be in a compressed state.

[0015] In this embodiment, the compressibility of the air foam can be 20% to 30%.

[0016] In an embodiment, the sum of the thickness of the compressed air foam and the thickness of the first adhesive layer can be approximately equal to the thickness of the second adhesive layer.

[0017] According to another aspect of this disclosure, a battery module includes: a plurality of battery cells arranged side-by-side along a first direction with their main surfaces facing each other, each battery cell including a lower vent; a heat insulation layer covering the lower vents of the plurality of battery cells; and a lower sheet located at the bottom of the heat insulation layer, wherein the lower sheet includes a first adhesive layer attached to the heat insulation layer and a second adhesive layer located on each of opposite sides of the first adhesive layer and attached to the lower surfaces of the plurality of battery cells, the heat insulation layer having a compressibility of 20% to 30% and being compressible.

[0018] In one embodiment, the insulation layer may extend in a direction substantially parallel to the first direction.

[0019] In an embodiment, the width of the insulation layer along a second direction perpendicular to the first direction may be greater than the width of the lower exhaust port along the second direction.

[0020] In one embodiment, the first adhesive layer may be thinner than the second adhesive layer.

[0021] In this embodiment, the thickness of the first adhesive layer can be from 0.01 mm to 0.03 mm.

[0022] In this embodiment, the thickness of the second adhesive layer can be from 0.3 mm to 0.7 mm.

[0023] In one embodiment, the insulation layer may include air foam.

[0024] In an embodiment, the second adhesive layer may be positioned spaced apart from the first adhesive layer.

[0025] In one embodiment, each of the plurality of battery cells may include an electrode terminal on the side opposite to the lower exhaust port.

[0026] In an embodiment, the sum of the thickness of the compressed insulation layer and the thickness of the first adhesive layer can be approximately equal to the thickness of the second adhesive layer.

[0027] Other aspects, features, and advantages, in addition to those described above, will become apparent from the following drawings, claims, and detailed description of the invention. Attached Figure Description

[0028] These and / or other aspects will become apparent and more readily understood from the following description of embodiments, taken in conjunction with the accompanying drawings, in which: Figure 1 This is a perspective view schematically illustrating an example of a battery module according to an embodiment of the present disclosure; Figure 2 It is shown schematically. Figure 1 A perspective view of an example of a single cell in a battery module; Figure 3 It is shown schematically. Figure 2 A cross-sectional view of section I-I' (example); Figure 4 It is a schematic illustration of the setting. Figure 1 A perspective view of an example of the bottom sheet and heat insulation layer at the bottom of the battery module; and Figure 5 and Figure 6 They are shown separately. Figure 2 A cross-sectional view showing the bonding relationship between the battery cell, the lower cell, and the heat insulation layer. Detailed Implementation

[0029] This disclosure can be modified in various ways and has various embodiments. Specific embodiments are shown in the accompanying drawings and described in detail in the specific embodiments. However, this is not intended to limit this disclosure to the particular embodiments, but should be understood to include all variations, equivalents, or substitutions included within the spirit and technical scope of this disclosure. In the description of this disclosure, detailed descriptions are omitted where it is determined that detailed descriptions of relevant known art may obscure the gist of this disclosure.

[0030] The terms "first," "second," etc., can be used to describe various components, but these components should not be limited by these terms. These terms are only used to distinguish one component from another.

[0031] The terminology used in this application is for describing particular embodiments only and is not intended to limit this disclosure. Singular expressions include plural expressions unless the context clearly indicates otherwise. Furthermore, in each drawing, components are exaggerated, omitted, or shown schematically for convenience and clarity of description, and the dimensions of each component do not perfectly reflect actual dimensions.

[0032] In the description of each component, when it is described as forming on top or below, both top and below include cases where it is formed directly or through the intervention of other components, and the criteria for top and below are interpreted based on the accompanying drawings.

[0033] In the following description, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. When describing with reference to the drawings, the same or corresponding components are assigned the same reference numerals, and redundant descriptions are omitted.

[0034] Figure 1 This is a perspective view schematically illustrating an example of a battery module according to an embodiment of the present disclosure. Figure 2 It is shown schematically. Figure 1 A perspective view of an example of a single cell in a battery module. Figure 3 It is shown schematically. Figure 2 An example sectional view of section I-I'.

[0035] Reference Figures 1 to 3 According to embodiments of the present disclosure, a battery module 100 may include a plurality of battery cells 10, the main surfaces of the plurality of battery cells 10 facing each other and arranged side by side along a first direction x, and each battery cell including a lower exhaust port 11.

[0036] like Figure 1 As shown, the battery module 100 according to this disclosure includes electrode terminals 21, 22, a plurality of battery cells 10 arranged in one direction, a connecting tab 26 connecting battery cells 10a to adjacent battery cells 10b, and a protection circuit module 30 having one end connected to the connecting tab 26. The protection circuit module 30 may be a battery management system (BMS). In some embodiments, the connecting tab 26 may include a body portion that contacts the electrode terminals 21, 22 between adjacent battery cells 10a, 10b, and an extension portion extending from the body portion and connecting to the protection circuit module 30. The connecting tab 26 may be a busbar.

[0037] First, the battery cell 10 may include a battery casing and an electrode assembly and an electrolyte housed within the battery casing. The electrode assembly and electrolyte undergo an electrochemical reaction to generate energy. One side of the battery cell 10 may be provided with electrode terminals 21, 22 electrically connected to connecting tabs 26, and a lower exhaust port 11 serving as an exhaust channel for internally generated gases. In some embodiments, the above description is given as an example of a series connection, but is not limited to this structure, and various connection structures may be employed as needed. In some embodiments, the number and arrangement of battery cells are not limited to... Figure 1 The structure shown can be modified as needed.

[0038] Multiple battery cells 10 can be arranged in one direction such that the wide surfaces of the battery cells 10 face each other, and the arranged battery cells 10 can be secured by housings 61, 62, and 63. Housings 61, 62, and 63 may include a pair of end plates 61 and 62 facing the wide surfaces of the battery cells 10, a side plate 63 connecting the pair of end plates 61 and 62, and a bottom plate. The side plate 63 supports the side surfaces of the battery cells 10, and the bottom plate supports the bottom surface of the battery cells 10. In some embodiments, the pair of end plates 61 and 62, the side plate 63, and the bottom plate can be connected by a component such as bolts 65.

[0039] The protection circuit module 30 is equipped with electronic components and protection circuits, and can be electrically connected to the connection piece 26 described below. The protection circuit module 30 includes a first protection circuit module 30a and a second protection circuit module 30b extending from different positions along the direction in which multiple battery cells 10 are arranged. In this case, the first protection circuit module 30a and the second protection circuit module 30b are spaced apart from each other but arranged parallel to each other to be electrically connected to the connection piece 26 adjacent to them.

[0040] In some embodiments, the first protection circuit module 30a is formed to extend on one upper side of the plurality of battery cells 10 along the direction in which the plurality of battery cells 10 are arranged, and the second protection circuit module 30b is formed to extend on the other upper side of the plurality of battery cells 10 along the direction in which the plurality of battery cells 10 are arranged. However, the second protection circuit module 30b is positioned at a certain distance from the first protection circuit module 30a, but can be arranged parallel to the first protection circuit module 30a, and the lower exhaust port 11 is placed between the second protection circuit module 30b and the first protection circuit module 30a.

[0041] In this way, the two protection circuit modules are arranged side by side and spaced apart from each other along the direction in which the multiple battery cells 10 are arranged, thereby minimizing the area of ​​the printed circuit board (PCB) constituting the protection circuit module.

[0042] Unnecessary PCB area is minimized by constructing the protection circuit module as two separate protection circuit modules. In an embodiment, the first protection circuit module 30a and the second protection circuit module 30b can be connected to each other via a conductive connecting member 55. In this case, one side of the connecting member 55 is connected to the first protection circuit module 30a, and the other side is connected to the second protection circuit module 30b, thereby enabling an electrical connection between the two protection circuit modules.

[0043] The connection can be made by any of the following methods: brazing, resistance welding, laser welding, or projection welding.

[0044] In some embodiments, the connecting member 55 may be, for example, an electrical wire. In some embodiments, the connecting member 55 may be made of a resilient or flexible material. Because of such a connecting member 55, the voltage, temperature, and current of multiple battery cells 10 can be checked and managed to ensure they are functioning correctly. That is, information regarding voltage, current, temperature, etc., received by the first protection circuit module from its adjacent connecting connector, and information regarding voltage, current, temperature, etc., received by the second protection circuit module from its adjacent connecting connector, can be integrated through the connecting member and managed by the protection circuit module.

[0045] In some embodiments, when the battery cell 10 expands, the impact can be absorbed by the elasticity or flexibility of the connecting member 55, thereby preventing damage to the first protection circuit module 30a and the second protection circuit module 30b.

[0046] In some embodiments, the shape and structure of the connecting member 55 are not limited to Figure 1 The shape shown.

[0047] In this way, because the protection circuit module 30 is provided with a first protection circuit module 30a and a second protection circuit module 30b, the area of ​​the PCB constituting the protection circuit module can be minimized, thereby ensuring space inside the battery module. This improves work efficiency by facilitating repairs when anomalies are detected in the battery module and the fastening of the connecting tabs 26 and the protection circuit module 30.

[0048] Reference Figure 2 and Figure 3 According to the embodiment, the battery cell 10 may include a housing 20 in which an electrode assembly 1000 is housed, a cover 31 engaged with an opening in the housing 20, and an electrolyte inlet 32.

[0049] like Figure 3 As shown, the battery cell 10 according to the embodiment may include: at least one electrode assembly 1000 wound between a positive electrode 1100 and a negative electrode 1200, a separator 1300 as an insulator placed between the positive electrode 1100 and the negative electrode 1200; a housing 20 in which the electrode assembly 1000 is housed; and cover assemblies 31, 32, and 33 engaged with openings in the housing 20.

[0050] As an example, the battery cell 10 according to the embodiment is described as a square lithium-ion secondary battery. However, this disclosure is not limited thereto, and this disclosure can be applied to various types of batteries, such as lithium polymer batteries or cylindrical batteries.

[0051] The positive electrode 1100 and the negative electrode 1200 may include coated portions and uncoated portions 1100a and 1200a. The coated portions are areas where active material is applied to a current collector formed of a thin metal foil, and the uncoated portions 1100a and 1200a are areas where no active material is applied.

[0052] A diaphragm 1300, which is wound around the positive electrode 1100 and the negative electrode 1200 and serves as an insulator, is placed therebetween. However, this disclosure is not limited thereto, and the electrode assembly 1000 described above may be formed in a structure in which positive and negative electrodes made of a plurality of sheets are alternately stacked and a diaphragm is placed therebetween.

[0053] The housing 20 forms the overall appearance of the battery cell 10 and can be formed of a conductive metal such as aluminum, aluminum alloy, or nickel-plated steel. In some embodiments, the housing 20 may provide space for accommodating the electrode assembly 1000.

[0054] Cover assemblies 31, 32, and 33 may include a cover plate 31 covering the opening of the housing 20, and the housing 20 and cover plate 31 may be made of a conductive material. Here, the positive electrode terminal 21 electrically connected to the positive electrode 1100 and the negative electrode terminal 22 electrically connected to the negative electrode 1200 may be mounted to protrude outward through the cover plate 31.

[0055] In some embodiments, the outer peripheral surfaces of the upper posts of the positive electrode terminal 21 and the negative electrode terminal 22 protruding outward from the cover plate 31 can be threaded and fixed to the cover plate 31 with nuts.

[0056] However, this disclosure is not limited thereto. The positive electrode terminal 21 and the negative electrode terminal 22 may be formed with a riveted structure and may be riveted or welded to the cover plate 31.

[0057] In some embodiments, the cover plate 31 may be made of a thin plate and may be engaged with an opening in the housing 20, and an electrolyte inlet 32 ​​in which a sealing plug 33 may be installed may be formed in the cover plate 31.

[0058] The positive electrode terminal 21 and the negative electrode terminal 22 can be electrically connected to a current collector including a first current collector 40 welded to the uncoated portion 1100a of the positive electrode and a second current collector 50 welded to the uncoated portion 1200a of the negative electrode (hereinafter referred to as the positive electrode current collector and the negative electrode current collector).

[0059] In some embodiments, the positive electrode terminal 21 and the negative electrode terminal 22 may be soldered to the positive electrode current collector 40 and the negative electrode current collector 50. However, this disclosure is not limited thereto, and the positive electrode terminal 21 and the positive electrode current collector 40 may be integrally formed, and the negative electrode terminal 22 and the negative electrode current collector 50 may be integrally formed.

[0060] In some embodiments, an insulating member may be installed between the electrode assembly 1000 and the cover plate 31. Here, the insulating member may include a first lower insulating member 60 and a second lower insulating member 70, each of which may be installed between the electrode assembly 1000 and the cover plate 31.

[0061] In some embodiments, according to the embodiment, one end of the separator member that can be mounted on the side facing the electrode assembly 1000 can be mounted between the insulating member and the positive electrode terminal 21 or the negative electrode terminal 22.

[0062] Here, the separation components may include a first separation component 80 and a second separation component 90.

[0063] Therefore, one end of the first separating member 80 and one end of the second separating member 90, which can be installed on the side facing the electrode assembly 1000, can be installed between the first lower insulating member 60 and the positive electrode terminal 21 and between the second lower insulating member 70 and the negative electrode terminal 22.

[0064] Finally, the positive electrode terminal 21 welded to the positive electrode current collector 40 and the negative electrode terminal 22 welded to the negative electrode current collector 50 can be combined with one end of the first lower insulating member 60 and the first separating member 80, as well as one end of the second lower insulating member 70 and the second separating member 90.

[0065] The battery cell 10 may include a lower vent 11 opposite to the electrode terminals 21, 22. In some embodiments, when the electrode terminals 21, 22 are located at the top, the lower vent 11 may be located at the bottom of the battery cell 10. When the internal pressure of the battery cell 10 increases due to overcharging, the lower vent 11 can ensure the stability of the battery cell 10 by releasing internal gases, flames, and ash.

[0066] When the internal pressure of the battery cell 10 is higher than the reference pressure, the lower vent 11 can open earlier than other areas. Therefore, the lower vent 11 can guide the internal gas of the battery cell 10 to be discharged to the outside earlier than the reference pressure, thereby preventing accidents such as explosions. In particular, when structures such as busbars for electrical connections of the battery module 100 are formed on the side or top of the battery module 100, these structures will not be affected even if the lower vent 11 of the battery cell 10 is opened, provided that the lower vent 11 is formed on the lower surface.

[0067] Figure 4 It is a schematic illustration of the setting. Figure 1 A perspective view of an example of the bottom sheet and heat insulation layer at the bottom of the battery module.

[0068] Reference Figure 4The heat insulation layer 110 and the lower sheet 130 can be attached to the bottom of the battery module 100 to cover the lower exhaust ports 11 of multiple battery cells 10.

[0069] The lower sheet 130 may include a first adhesive layer 131 attached to the heat insulation layer 110 and a second adhesive layer 132 located on each of the opposite sides of the first adhesive layer 131 and attached to the lower surface of the plurality of battery cells 10.

[0070] In some embodiments, the insulation layer 110 may extend in a direction parallel to the first direction x.

[0071] Therefore, the first adhesive layer 131 and the second adhesive layer 132, which are installed to overlap with the heat insulation layer 110, can also extend in a direction parallel to the first direction x and overlap with the lower surface of the battery module 100.

[0072] In some embodiments, the extension length of the lower sheet 130 and the heat insulation layer 110 may be equal to the length of the battery module 100.

[0073] The first adhesive layer 131 may be located in the lower central portion of the battery module 100. The second adhesive layer 132 is located on opposite sides of the first adhesive layer 131, and the total area of ​​the second adhesive layer 132 and the first adhesive layer 131 bonded to the bottom of the battery module 100 is determined to be no more than the area of ​​the length of the battery module 100 in the second direction y and the length of the battery module 100 in the first direction x.

[0074] Therefore, the width of the lower sheet 130 can be manufactured to be the same as the width of the battery module 100, so that the battery module 100 can be mounted on the lower sheet 130. This prevents the adhesive layers 131, 132 from protruding beyond the lower surface of the battery module 100 and from being contaminated by external pollutants such as dust.

[0075] In some embodiments, the first adhesive layer 131, the second adhesive layer 132, and the heat insulation layer 110 may have a rectangular shape for stacking with the battery module 100, but are not limited thereto.

[0076] The first adhesive layer 131 and the second adhesive layer 132 may include adhesives on both surfaces. In some embodiments, any method that can bond the two surfaces may be used.

[0077] In some embodiments, the first adhesive layer 131 and the second adhesive layer 132 may be double-sided tape, but are not limited thereto.

[0078] In some embodiments, since the second adhesive layer 132 is stacked on the bottom of the battery module 100 and the first adhesive layer 131 is bonded to the heat insulation layer 110, the required adhesive strength of each of the adhesive layers 131 and 132 may be different. Therefore, the first adhesive layer 131 and the second adhesive layer 132 may use different adhesives or different amounts of adhesive.

[0079] The first adhesive layer 131 and the second adhesive layer 132 can be attached to the battery module 100 at the same time as the guide 140. After the first adhesive layer 131 and the second adhesive layer 132 are attached to the battery module 100, the guide 140 can be removed.

[0080] In some embodiments, the first adhesive layer 131 may be located at the center of the top of the guide 140, the second adhesive layer 132 may be located on opposite sides of the first adhesive layer 131 and spaced apart from the first adhesive layer 131, and the heat insulation layer 110 may be located on top of the first adhesive layer 131.

[0081] In some embodiments, the guide 140 has a coated outer surface that allows it to be easily removed from the first adhesive layer 131 and the second adhesive layer 132. The coating material of the guide 140 may be PVC, PET, OPP, etc., but is not limited thereto.

[0082] Figure 5 and Figure 6 Each is shown Figure 2 A cross-sectional view showing the bonding relationship between the battery cell, the lower cell, and the heat insulation layer.

[0083] like Figure 5 As shown, the lower sheet 130 can cover the lower surface of the battery cell 10.

[0084] Thus, the heat insulation layer 110 is attached to overlap with the lower exhaust port 11 of the battery cell 10 and can block flames, gases and ash coming out of the lower exhaust port 11.

[0085] In some embodiments, the heat insulation layer 110 superimposed on the lower exhaust port 11 is made of a material with low thermal conductivity and is selected as a material that is not easily damaged by flame.

[0086] In some embodiments, the insulation layer 110 may include air foam for high insulation.

[0087] Air bubbles can include aerogels, the main component of which is silicon dioxide (SiO2). Furthermore, the size of aerogel particles can range from 10 μm to 100 μm, and aerogel particles can have nanoscale dimensions.

[0088] In some embodiments, in a conventional battery module 100, when thermal runaway occurs in a battery cell 10, ash or gas may easily flow into the adjacent battery cell 10 due to the gap between the base plate and the lower exhaust port 11, which may cause heat transfer in the adjacent battery cell 10.

[0089] On the other hand, according to this disclosure, the heat insulation layer 110 and the first adhesive layer 131 and the second adhesive layer 132 included in the lower sheet 130 replace the conventional base plate to cover the entire lower surface of the battery module 100, and because the heat insulation layer 110, which has high heat insulation properties, is positioned to overlap with the lower vent 11, flames, gases, and ash from the lower vent 11 are less likely to diffuse to adjacent cells. In some embodiments, the second adhesive layer 132 can secure a plurality of battery cells 10 included in the battery module 100. Therefore, heat transfer to surrounding battery cells 10 due to thermal runaway of the battery cells 10 can be prevented.

[0090] In some embodiments, the second adhesive layer 132 may be positioned spaced apart from the first adhesive layer 131.

[0091] In some embodiments, the distance between the first adhesive layer 131 and the second adhesive layer 132 in the second direction y can be 0.5 mm to 1.5 mm on each side. The first adhesive layer 131 and the second adhesive layer 132 are spaced apart to minimize interference between the adhesive layers, and the spacing distance d can increase the accuracy of attaching the heat insulation layer 110 to the first adhesive layer 131.

[0092] When the spacing d is less than 0.5 mm, the heat insulation layer 110 attached to the top of the first adhesive layer 131 may extend beyond the area of ​​the second adhesive layer 132, thereby reducing the adhesive force to the battery module 100. Furthermore, when the spacing d exceeds 1.5 mm, the gas and flame from the lower exhaust port 11 may move within the spacing d. In some embodiments, the spacing d is considered to be slightly larger than the thickness of the second adhesive layer 132, thereby preventing the adhesive layers 131 and 132 from adhering to each other.

[0093] The width of the heat insulation layer 110 along the second direction y, which is perpendicular to the first direction x, can be greater than the width of the lower exhaust port 11 along the second direction y.

[0094] In some embodiments, the width of the insulation layer 110 may be approximately 10% to 20% wider than the width of the lower exhaust port 11. However, it is not limited thereto, and the size of the insulation layer 110 may be varied depending on the size of the lower exhaust port 11.

[0095] When the width of the heat insulation layer 110 is about 10% larger than the width of the lower vent 11, the lower vent 11 is not adequately covered, and flames may easily escape from the heat insulation layer 110. In some embodiments, when the width of the heat insulation layer 110 exceeds the width of the lower vent 11 by more than about 20%, the width of the second adhesive layer 132 attached to the bottom of the battery module 100 decreases, making it difficult to adequately secure the battery cell 10.

[0096] Therefore, the width of the insulation layer 110 is formed to be 10% to 20% larger than the width of the lower exhaust port 11.

[0097] In other words, since the heat insulation layer 110 has a width wider than the lower exhaust port 11, the gas, flame, ash, etc. discharged from the lower exhaust port 11 of the battery cell 10 will not escape, and heat transfer between battery cells 10 can be effectively prevented.

[0098] The first adhesive layer 131 may be thinner than the second adhesive layer 132. In some embodiments, the thickness of the first adhesive layer 131 may be from 0.01 mm to 0.03 mm, and the thickness of the second adhesive layer 132 may be from 0.3 mm to 0.7 mm.

[0099] When the first adhesive layer 131 is less than 0.01 mm, it is too thin and may be easily torn, or it may be easily damaged during the attachment of the sheet 130. On the other hand, when the first adhesive layer 131 is more than 0.03 mm, the height when it is added to the insulation layer 110 may be greater, resulting in a large space occupation.

[0100] In some embodiments, with the second adhesive layer 132, when the thickness is less than 0.3 mm, the fixing force for fixing the bottom of the battery module 100 may be reduced, and when the thickness exceeds 0.7 mm, the overall height of the battery module 100 increases, which may reduce space efficiency and make it difficult to construct a compact battery module 100.

[0101] As described above, the lower sheet 130 with a first adhesive layer 131 and a second adhesive layer 132 of different thicknesses can create a step between the relatively thin first adhesive layer 131 and the relatively thick second adhesive layer 132. By using the step between the first adhesive layer 131 and the second adhesive layer 132 to fix the heat insulation layer 110, the mechanical stability of the battery module 100 can be improved.

[0102] In some embodiments, the relatively thick second adhesive layer 132 is less prone to tearing compared to the relatively thin first adhesive layer 131, and more adhesive can be applied to the relatively thick second adhesive layer 132 compared to the relatively thin first adhesive layer 131, thereby improving the adhesive strength.

[0103] In some embodiments, the adhesive may include, but is not limited to, rubber, terpene resin, silicone resin, and acrylate.

[0104] like Figure 6 As shown, the heat insulation layer 110 can be in a compressed state due to the weight of the battery module.

[0105] At this point, the compressibility of the insulation layer 110 can be 20% to 30%. Here, the compressibility of the insulation layer 110 refers to the degree of compression based on the maximum compressibility state of the insulation layer 110.

[0106] Generally, as the density of insulating materials increases, their thermal conductivity decreases, which is beneficial for improving insulation performance.

[0107] When the compressibility of the heat insulation layer 110 is less than 20%, the heat insulation layer 110 may not have sufficient insulation, making it difficult to block flames and other gases coming out through the lower exhaust port 11. When the compressibility exceeds 30%, it may be difficult to allow the gas coming out of the lower exhaust port 11 to be discharged smoothly, which may reduce the stability of the battery module 100.

[0108] In other words, when the compressibility is 20% to 30%, the defect rate can be steadily reduced during the process of attaching the battery module 100 to the lower sheet 130, and the heat transfer of the lower exhaust port 11 can be effectively blocked.

[0109] In this configuration, the step height of the lower sheet 130 formed by the first adhesive layer 131 and the second adhesive layer 132 is designed to be less than the height of the lower sheet 130 of the standard battery module 100, while the height of the compressed heat insulation layer 110 and the first adhesive layer 131 is designed to be the same as the height of the second adhesive layer 132, so that the surfaces of the heat insulation layer 110 and the second adhesive layer 132 are on the same plane, thereby ensuring that the lower surfaces of the battery module 100 are in close contact with each other.

[0110] In other words, the sum of the thickness of the compressed insulation layer 110 and the thickness of the first adhesive layer 131 can be equal to the thickness of the second adhesive layer 132.

[0111] After the attachment of the lower sheet 130, the final height d' of the lower sheet 130 is equal to the height of the second adhesive layer 132, and the height of the second adhesive layer 132 is equal to the sum of the heights of the first adhesive layer 131 and the heat insulation layer 110.

[0112] After compression, the thickness of the heat insulation layer 110 can be formed to be the same as the height difference between the first adhesive layer 131 and the second adhesive layer 132. This allows the surface of the heat insulation layer 110 and the surface of the second adhesive layer 132 to be on the same plane at the same time, thereby increasing the adhesion between the battery cell 10 and the lower sheet 130 and fixing the battery cell 10 and the lower sheet 130 so that they are not easy to fall off each other.

[0113] This effectively seals the lower sheet 130 and the insulation layer 110 to the lower vent 11, thereby effectively blocking flames, gases and ash from the lower vent 11 to prevent heat transfer.

[0114] Therefore, the high-density heat insulation layer 110 compressed by the battery module 100 has higher insulation than the heat insulation layer 110 before compression, and the height plane formed by the lower sheet 130 and the heat insulation layer 110 is the same, so that it is in close contact with the lower exhaust port 11 located at the bottom of the battery module 100, thereby reducing the degree of damage to the battery cell 10 caused by the flame from the lower exhaust port 11, and effectively reducing heat transfer compared with the use of a conventional base plate.

[0115] In some embodiments, as described above, the first adhesive layer 131, the second adhesive layer 132, and the heat insulation layer 110 can be used to fix the battery cell 10 by replacing the base plate. Since the height of the lower sheet 130 and the heat insulation layer 110 after assembly is 0.3 mm to 0.7 mm, the space occupied by the existing base plate can be saved, thereby making the battery module 100 designed to be compact.

[0116] In some embodiments, the base plate made of existing metal can be replaced by the heat insulation layer 110 and the adhesive layers 131, 132 to reduce the conduction between the battery cell 10 and the casing 61, 62, 63.

[0117] Even if thermal runaway occurs in a single battery cell, the battery module according to this disclosure can improve stability by preventing the spread of flames or the like to adjacent battery cells.

[0118] Although the embodiments described above have been illustrated with reference to the accompanying drawings, these are merely exemplary, and those skilled in the art will understand that various modifications and equivalent embodiments are possible. Therefore, the true scope of protection of this disclosure should be determined by the technical concept of the appended claims.

Claims

1. A battery module, the battery module comprising: Multiple battery cells are arranged side-by-side along a first direction, with their main surfaces facing each other. Each battery cell includes a lower exhaust port. A heat insulation layer covering the lower exhaust ports of the plurality of battery cells, and The lower sheet is located below the heat insulation layer, wherein, The lower sheet includes: a first adhesive layer attached to the heat insulation layer; and a second adhesive layer located on each of the opposite sides of the first adhesive layer and attached to the lower surface of the plurality of battery cells. The second adhesive layer is positioned to be spaced apart from the first adhesive layer.

2. The battery module as described in claim 1, wherein, The insulation layer extends in a direction parallel to the first direction.

3. The battery module as described in claim 1, wherein, The width of the insulation layer along a second direction perpendicular to the first direction is greater than the width of the lower exhaust port along the second direction.

4. The battery module as described in claim 1, wherein, The first adhesive layer is thinner than each of the second adhesive layers.

5. The battery module as described in claim 1, wherein, The thickness of the first adhesive layer is 0.01 mm to 0.03 mm.

6. The battery module as described in claim 1, wherein, The thickness of the second adhesive layer is 0.3 mm to 0.7 mm.

7. The battery module as described in claim 1, wherein, The insulation layer includes air foam.

8. The battery module as described in claim 7, wherein, The air foam is in a compressed state.

9. The battery module as described in claim 8, wherein, The compressibility of the air foam is 20% to 30%.

10. The battery module as described in claim 9, wherein, The sum of the thickness of the compressed air foam and the thickness of the first adhesive layer is equal to the thickness of each of the second adhesive layers.

11. A battery module, the battery module comprising: Multiple battery cells are arranged side-by-side along a first direction, with their main surfaces facing each other. Each battery cell includes a lower exhaust port. A heat insulation layer covering the lower exhaust ports of the plurality of battery cells, and The lower sheet is located below the heat insulation layer, wherein, The lower sheet includes: a first adhesive layer attached to the heat insulation layer; and a second adhesive layer located on each of the opposite sides of the first adhesive layer and attached to the lower surface of the plurality of battery cells. The insulation layer has 20% to 30% compressibility and is compressed.

12. The battery module as described in claim 11, wherein, The insulation layer extends in a direction parallel to the first direction.

13. The battery module as described in claim 11, wherein, The width of the insulation layer along a second direction perpendicular to the first direction is greater than the width of the lower exhaust port along the second direction.

14. The battery module as described in claim 11, wherein, The first adhesive layer is thinner than each of the second adhesive layers.

15. The battery module as described in claim 11, wherein, The thickness of the first adhesive layer is 0.01 mm to 0.03 mm.

16. The battery module as described in claim 11, wherein, The thickness of each of the second adhesive layers is 0.3 mm to 0.7 mm.

17. The battery module as claimed in claim 11, wherein, The insulation layer includes air foam.

18. The battery module as described in claim 11, wherein, The second adhesive layer is positioned to be spaced apart from the first adhesive layer.

19. The battery module as described in claim 11, wherein, Each of the plurality of battery cells includes an electrode terminal on the opposite side of the lower exhaust port.

20. The battery module as described in claim 11, wherein, The sum of the thickness of the compressed insulation layer and the thickness of the first adhesive layer is equal to the thickness of each of the second adhesive layers.

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