Safety-enhanced battery modules and battery packs

Abstract

A battery module according to the present invention includes a cell assembly including a plurality of stacked battery cells; a module case that houses the cell assembly in an internal space; and a cover unit coupled to an outer surface of the module case and having a barrier layer disposed between the module case and the cover unit to block the entry and exit of flames and reduce heat transfer, wherein the barrier layer may be foamed and coupled to the cover unit, and may be provided integrally with the cover unit.

Description

[Technical Field]

[0001] The present invention relates to a battery module and a battery pack, and more particularly, to a battery module and a battery pack that, when a thermal event occurs, can delay heat transfer as much as possible by blocking the entry and exit of flames and minimizing heat transfer such as heat conduction and heat radiation.This application claims priority to Korean Patent Application No. 10-2023-0123386, filed on September 15, 2023, the entire contents of which are incorporated herein by reference in their entirety. [Background technology]

[0002] Semi-permanent batteries that convert electrical energy into chemical energy and can be repeatedly charged and discharged are called secondary batteries, in distinction from primary batteries, which cannot be reused once used.

[0003] Secondary batteries include lithium-ion secondary batteries, nickel-cadmium (Ni-Cd) batteries, lead-acid batteries, nickel-metal hydride (Ni-MH) batteries, zinc-air batteries, alkaline manganese batteries, etc. Of these, lead-acid batteries and lithium-ion secondary batteries are considered to be the most actively commercialized secondary batteries.

[0004] In particular, lithium-ion secondary batteries have recently been actively used as batteries for electric vehicles because they have advantages such as high energy storage density, lightweight and compact size, excellent safety, low discharge rate, and long life.For reference, lithium-ion secondary batteries are generally classified into cylindrical, prismatic, and pouch types depending on the manufacturing format, and their uses include not only electric vehicle batteries but also ESS batteries and other electrical devices.

[0005] Currently, the operating voltage of one lithium-ion secondary battery cell is approximately 2.5 V to 4.5 V. Therefore, in order to use a secondary battery as an energy source for an electric vehicle, a battery module is constructed by connecting multiple lithium-ion battery cells in series and / or in parallel, and a battery pack is constructed by connecting the battery modules in series and / or in parallel.

[0006] On the other hand, secondary batteries undergo chemical reactions during charging and discharging, so their performance may decrease if they are used in an environment that is higher than the appropriate temperature, and if they are not thermally controlled to the appropriate temperature, they may unexpectedly catch fire or explode.In addition, battery modules are constructed with such secondary batteries housed together inside a module housing, and if one of the secondary batteries experiences thermal runaway and becomes a trigger cell, the heat and flames will rapidly spread to the surrounding secondary batteries (thermal propagation), making the secondary batteries more susceptible to chain fires.

[0007] Therefore, a cover part is provided on the outer surface of the battery module to prevent chain ignition and heat transfer to adjacent battery modules, and such a cover part may typically be composed of multiple layers. For example, the cover part may have a layered structure in which a frame cover corresponding to the shape of the outer surface of the battery module and at least one inner skin layer are bonded within the frame cover.

[0008] Such covers are typically made of fire-resistant materials and can meet fire resistance requirements for heat resistance, but may have limitations in effectively blocking and delaying the transfer of flames between modules or heat conduction and heat radiation when a thermal event occurs. Therefore, there is a need for structural improvements to the cover that can block the ingress and egress of flames and minimize heat transfer, such as heat conduction and heat radiation.

[0009] Furthermore, an additional adhesive layer is interposed during the bonding process between the frame cover and the inner skin layer, and the inner skin layer may peel off due to flame or high heat, so there is a need to improve the durability of the cover portion.

[0010] Furthermore, in the existing manufacturing process of the cover, the frame cover and the inner skin layer are provided for each part, and separate bonding and punching processes are required, which increases the takt time and manufacturing costs of the module manufacturing process and reduces productivity. Summary of the Invention [Problem to be solved by the invention]

[0011] The present invention has been made in consideration of the above problems, and the problem to be solved by the present invention is to provide a battery module that, when a thermal event occurs, can block the entry and exit of flames and minimize heat transfer such as thermal conduction and thermal radiation, thereby suppressing flame propagation between modules and delaying chain heat transfer as much as possible, and can reduce takt time in the module manufacturing process and reduce manufacturing costs by eliminating the additional bonding and punching processes for each part required in the manufacturing process of the existing cover part for flame protection.

[0012] Another problem to be solved by the present invention is to provide a battery pack including such a battery module.

[0013] The technical problems that the present invention aims to solve are not limited to the above problems, and other problems not mentioned will be clearly understood by those skilled in the art from the description of the invention given below. [Means for solving the problem]

[0014] A battery module according to the present invention for solving the above problems includes a cell assembly having a plurality of stacked battery cells; a module case that houses the cell assembly in an internal space; and a cover unit coupled to an outer surface of the module case and having a barrier layer disposed between the module case and the cover unit to block the entry and exit of flames and reduce heat transfer, wherein the barrier layer is foamed and coupled to the cover unit and is provided integrally with the cover unit.

[0015] The barrier layer may be provided on an inner wall of the cover portion on the side facing the cell assembly.

[0016] The barrier layer may be a foam layer that is foamed to a predetermined thickness and attached to the inner wall of the cover portion.

[0017] The cover may be provided to cover an upper surface of the module case, or to cover the upper surface of the module case and both side surfaces in the length direction of the module case.

[0018] The cover portion may include a first cover member that covers an upper surface of the module case, and a pair of second cover members that cover both side surfaces in the length direction of the module case.

[0019] The barrier layer may be provided on the inner wall of the first cover member, or on the inner walls of the first cover member and the second cover member.

[0020] The module case has one or more vent holes formed therein, and the cover portion and the insulating layer have exhaust slits communicating with the vent holes, and the exhaust slits can be formed simultaneously by pressing the cover portion and the insulating layer.

[0021] An adhesive layer may be interposed between the barrier layer and the module case.

[0022] The barrier layer may include a polyurethane or silicone material.

[0023] The second cover member may have at least one recessed portion formed at regular intervals.

[0024] The second cover member may have a connecting sleeve formed thereon, the connecting sleeve being spaced apart by the thickness of the barrier layer and arranged along the length of the cover portion, to which a jig that guides the shape of the barrier layer when the barrier layer is foamed can be detachably connected.

[0025] The cell assembly may be provided with a second insulating layer disposed between each of the battery cells and attached by foaming.

[0026] The module case may be provided with a third barrier layer that is foamed and attached to the upper surface of the cell assembly and the interior space of the module case.

[0027] Furthermore, according to the present invention, a battery pack including the above-mentioned battery module can be provided.

[0028] Furthermore, according to the present invention, it is possible to provide a vehicle including the above-described battery pack. [Effects of the Invention]

[0029] According to one aspect of the present invention, a blocking layer is foamed and bonded to the cover portion, thereby blocking the entry and exit of flames when a thermal event occurs, and minimizing heat transfer such as thermal conduction and thermal radiation, thereby suppressing flame propagation between modules and delaying cascading heat transfer as much as possible.

[0030] Furthermore, according to one aspect of the present invention, the barrier layer is integrally bonded to the cover portion, thereby eliminating the adhesive layer between the existing cover portion and the barrier layer, simplifying the layered structure of the cover portion, and improving durability by making it relatively resistant to flames or high temperatures.

[0031] Furthermore, according to one aspect of the present invention, it is possible to eliminate the additional bonding and punching steps that were previously required in the manufacturing process of the flame-blocking cover for each component, thereby shortening the takt time in the module manufacturing process and reducing manufacturing costs, thereby improving productivity.

[0032] As described above, according to the present invention, the entry and exit of flames from a trigger module including a trigger cell to an adjacent battery module is blocked, heat transfer such as heat conduction and heat radiation can be minimized, and heat propagation between battery modules can be delayed, thereby enhancing the safety of the battery modules.

[0033] Furthermore, the battery pack of the present invention can enhance safety by including such a battery module.

[0034] The following drawings attached to this specification illustrate preferred embodiments of the present invention and, together with the detailed description of the invention, serve to further understand the technical concepts of the present invention. Therefore, the present invention should not be interpreted as being limited to only the matters described in the drawings. [Brief explanation of the drawings]

[0035] [Figure 1] 1 is a schematic perspective view of a battery module according to an embodiment of the present invention; [Figure 2] FIG. 2 is an exploded perspective view of the main components of the battery module of FIG. 1. [Figure 3] 2 is a vertical cross-sectional view of the battery module of FIG. 1 taken along line AA'. FIG. [Figure 4] FIG. 4 is an enlarged view of part B in FIG. [Figure 5] 3 is an exploded perspective view of a cover of a battery module according to an embodiment of the present invention; FIG. [Figure 6] 5 is a diagram showing a modified example of the cover part of FIG. 4, which is provided so as to cover the upper surface of the module case. FIG. [Figure 7] 5 is a diagram showing a modified example of the cover portion of FIG. 4. FIG. [Figure 8] 10A and 10B are views showing a cover part of a battery module according to a second embodiment of the present invention. [Figure 9] 10A and 10B are views showing a cover part of a battery module according to a third embodiment of the present invention. [Figure 10] FIG. 10 is a longitudinal sectional view of a battery module according to a fourth embodiment of the present invention. [Figure 11] 1 is a diagram illustrating a battery pack according to an embodiment of the present invention; [Figure 12] 1 is a diagram for explaining an automobile according to an embodiment of the present invention; DETAILED DESCRIPTION OF THE INVENTION

[0036] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, the terms and phrases used in the specification and claims should not be construed as being limited to their ordinary and dictionary meanings, but should be construed as having meanings and concepts corresponding to the technical ideas of the present invention, in accordance with the principle that the inventors themselves can appropriately define the concepts of terms in order to best describe the invention.

[0037] Therefore, it should be understood that the configurations shown in the embodiments described in this specification are merely the most desirable embodiments of the present invention and do not represent the entire technical idea of ​​the present invention, and that there may be various equivalents and modifications that can be substituted therefor at the time of this application.

[0038] FIG. 1 is a schematic perspective view of a battery module according to one embodiment of the present invention, and FIG. 2 is an exploded perspective view of the main components of the battery module of FIG.

[0039] 1 and 2, a battery module 10 according to the present invention includes a cell assembly 100, a module case 200, and a cover part 300.

[0040] The cell assembly 100 may include one or more battery cells 110. Here, each battery cell 110 may refer to a secondary battery. The battery cell 110 refers to a secondary battery including an electrode assembly, an electrolyte, and a pouch case that houses the electrode assembly. In the present embodiment, a pouch-type battery cell 110 that has high energy density and is easy to stack is targeted, but it goes without saying that a cylindrical or prismatic secondary battery can also be used as the battery cell 110.

[0041] 2, the pouch-type battery cell 110 includes an electrode assembly, a case that houses the electrode assembly, and a pair of electrode leads 112 that are connected to the electrode assembly and extend outside the case to function as electrode terminals. The pair of electrode leads 112 may extend forward and backward along the length of the battery cell 110 (±Y directions). Alternatively, if necessary, the electrode leads 112 may be located only at one end in the Y-axis direction, for example, at the end in the −Y-axis direction. Electrical components such as a bus bar 113 and a bus bar frame 114, as well as a cell case 111, may be provided adjacent to the pair of electrode leads 112 of the battery cell 110.

[0042] Such battery cells 110 may be stacked and arranged in at least one direction. In the present embodiment, referring mainly to FIG. 2, the battery cells 110 may be stacked and arranged in a horizontal direction (the width direction of the battery module 10, the X-axis direction) while standing upright in the vertical direction (the Z-axis direction).

[0043] The cell assembly 100 is an assembly of battery cells 110 formed by stacking a plurality of battery cells 110. That is, as shown in Fig. 2, the cell assembly 100 may be an assembly of a plurality of pouch-type battery cells 110 stacked in one direction (X-axis direction) with the wide surfaces of the battery cells 110 standing upright.

[0044] The module case 200 may have an internal space formed therein and may be configured to accommodate a plurality of battery cells 110. The module case 200 is a component for protecting the cell assembly 100 from external impacts, and may be preferably manufactured from a material with excellent mechanical rigidity. The module case 200 of the present embodiment may include a case body 210 and end plates 220 disposed on the front and rear surfaces of the case body 210.

[0045] The case body 210 may have open ends O at both ends in the length direction (Y-axis direction) and may be configured in a rectangular tube shape having a hollow structure. For example, the case body 210 may have an upper surface, a lower surface, a left side surface, and a right side surface, and may be configured in a tube shape with openings formed at the front and rear ends.

[0046] Alternatively, the module case 200 may be formed in various other shapes. For example, the case body 210 may be formed by integrating a left side plate, a right side plate, and a bottom plate. In this case, the integrated case portion may be called a U-frame. The U-frame may be formed in a tubular shape by welding a top plate to the upper surface. Alternatively, the module case 200 may have a box-shaped lower case in which the left side plate, the right side plate, the front plate, and the rear plate are integrated, and an upper cover that closes the upper open end of the lower case.

[0047] The case body 210 may be configured to allow the cell assembly 100 to be inserted into the interior along the length direction. That is, the case body 210 may be configured to allow the multi-layered battery cells 110 to be inserted therein by sliding or interference fit. For the interference fit connection, there may be little gaps between the upper and lower surfaces of the case body 210 and between the upper and lower ends of the battery cells 110, and there may also be little gaps between both side surfaces of the case body 210 and both sides of the battery cells 110. The case body 210 may be made of a metal material having rigidity and heat resistance to physically and chemically protect the housed battery cells 110.

[0048] The end plates 220 may be disposed at both longitudinal ends of the cell assembly 100, i.e., at the front and rear ends, where the electrode leads of the battery cells 110 are located, and may be configured to be coupled to the open end O of the case body 210. The end plates 220 are configured to cover connection portions between the bus bar frame and the electrode leads when the electrode leads of the battery cells 110 are connected to the bus bar frame so as not to be exposed to the outside. For example, the inside of the end plates 220 may be formed of an insulating material and the outside of the end plates 220 may be formed of a metallic material, and may be configured to be fixedly coupled to the case body 210 by welding. Meanwhile, although not shown for convenience of illustration, the end plates 220 may have holes or slits partially formed therein to expose components that need to be exposed to the outside, such as the positive and negative terminals or connectors of the battery module 10.

[0049] The module case 200 configured as described above may have a vent hole H formed on at least one side thereof. The vent hole H may be configured to allow discharge of discharged materials such as vent gas from the interior space of the module case 200 to the outside when the discharged materials are generated and ejected from the cell assemblies 100 housed in the interior space. For example, the module case 200 may be configured in a sealed form except for the vent hole H. Alternatively, the vent hole H may be formed in a completely open form so as to penetrate the module case 200 inward and outward directions.

[0050] In this embodiment, the vent hole H may have a predetermined width in the width direction of the module case 200 and may be formed in the shape of a long hole extending in the length direction of the module case 200. Also, as shown by H in Fig. 2, a plurality of vent holes H may be formed on the upper side of the module case 200. Meanwhile, the number and shape of the vent holes H may vary, and the positions at which the vent holes H are disposed may also be changed as necessary.

[0051] The cover part 300 may be coupled to an outer surface of the module case 200. In this embodiment, the cover part 300 may be provided to cover an upper surface of the module case 200 and both side surfaces of the module case 200 in the length direction.

[0052] The cover part 300 may be provided to cover the upper surface of the module case 200. As a result, it may be configured to cover the vent hole H formed on the upper surface of the module case 200. In addition, the cover part 300 may be provided on both sides in the width direction (X-axis direction) (or both sides in the length direction (Y-axis direction)) of the module case 200 to cover both side surfaces of the module case 200. As a result, the cover part 300 may be coupled to the outer surfaces (upper surface and both side surfaces) of the module case 200.

[0053] The cover part 300 may be provided with a discharge slit 311. The discharge slit 311 may be provided to communicate with the vent hole H.

[0054] FIG. 3 is a partial cross-sectional view of the upper side of a battery module according to one embodiment of the present invention, and FIG. 4 is an exploded perspective view of a cover part of the battery module according to one embodiment of the present invention.

[0055] In addition, the cover 300 must effectively block, reduce, and delay the flames and intense heat generated by a thermal event.

[0056] Referring to FIGS. 3 and 4 and FIG. 2, the cover part 300 in this embodiment may include a blocking layer 400.

[0057] The barrier layer 400 may be provided on the inner wall of the cover portion 300 on the side facing the cell assembly 100. This allows the barrier layer 400 to be disposed between the cover portion 300 and the module case 200.

[0058] The barrier layer 400 may be foamed and bonded to the cover part 300, and may be provided integrally with the cover part 300. For example, the barrier layer 400 may be a foam layer foamed to a predetermined thickness and attached to the inner wall of the cover part 300. The barrier layer 400 is foamed directly onto the cover part 300, and no bonding means such as an adhesive layer for bonding the barrier layer 400 and the cover part 300 is required.

[0059] However, an adhesive layer 350 may be interposed between the cover part 300 including the barrier layer 400 and the module case 200. The adhesive layer 350 is used to attach the cover part 300 to the module case 200.

[0060] The barrier layer 400 may have an exhaust slit 411 that communicates with the vent hole H. As a result, vent gas generated in the battery module 10 can be easily exhausted to the outside of the battery module 10 through the exhaust slit 411 of the barrier layer 400 and the exhaust slit 311 of the cover part 300.

[0061] According to this embodiment, the blocking layer 400 is foamed and bonded to the cover part 300, so that when a thermal event occurs, the ingress and egress of flames is blocked and heat transfer such as heat conduction and heat radiation can be reduced and minimized.

[0062] Furthermore, according to this embodiment, the blocking layer 400 is integrally bonded to the cover portion 300 in a foamed state, thereby eliminating the adhesive layer between the layered structure of the existing cover portion 300 (between the cover portion 300 and the blocking layer 400), which will be described in more detail later.

[0063] FIG. 5 is an exploded perspective view of a cover portion of a battery module according to one embodiment of the present invention.

[0064] 5 and again with reference to FIGS. 2 to 4, the cover portion 300 and the blocking layer 400 will be described in detail.

[0065] The cover part 300 is a part that is coupled to the outer surfaces (top and side surfaces) of the module case 200 to retard heat transfer, and for this purpose, the cover part 300 may include a first cover member 310 and a pair of second cover members 320.

[0066] The first cover member 310 may be a part that covers an upper surface of the module case 200. An exhaust slit 311 may be formed on a plate surface of the first cover member 310. The exhaust slit 311 may be provided to communicate with the vent hole H and may be provided on the plate surface of the cover part 300 to correspond to the shape of the vent hole H. The exhaust slit 311 may be provided with one or more bridges 312.

[0067] The second cover member 320 may be a portion that covers both side surfaces in the length direction of the module case 200. The second cover member 320 may be provided by bending vertically downward from both side portions in the width direction (X-axis direction) of the module case 200 (or both side portions in the length direction (Y-axis direction)).

[0068] The cover 300 may be made of a material that is fire-resistant or heat-resistant. Preferably, the fire-resistant layer may be VO grade or higher in the UL 94 test. The fire-resistant layer may be made of an inorganic material (e.g., a fire retardant barrier (FRB) material), a MICA material, a fire-resistant plastic, or a combination thereof. This ensures that the battery module 10 is heat-resistant against high-temperature ejecta, such as vent gas, flames, or sparks, generated in an adjacent battery module during a thermal event. Furthermore, in the case of a battery module 10 including a trigger cell, the battery module 10 may delay the outflow of ejecta generated internally to the outside or the time for heat transfer to an adjacent module. Meanwhile, it goes without saying that the fire-resistant layer may be made of a material that is fire-resistant or heat-resistant in addition to the above-mentioned materials.

[0069] As described above, the blocking layer 400 may be an expanded foam layer that is foamed and bonded to the cover part 300, is integrally provided on the cover part 300, and is foamed to a predetermined thickness and attached to the inner wall of the cover part 300. Referring mainly to FIG. 5, the expanded foam layer may be bonded to the inner wall of the first cover member 310 of the cover part 300.

[0070] The barrier layer 400 may include polyurethane or silicone material, and the material of the barrier layer 400 may block the ingress and egress of flames and minimize heat transfer, such as heat conduction and heat radiation.

[0071] In addition, since the blocking layer 400 is made of an expanded foam layer, the particle structure of the expanded foam layer allows for the inclusion of fine air layers within the layer, thereby cushioning external impacts and absorbing external forces and impacts. In addition, since the blocking layer 400 is expanded to form a layer and occupies space, it can be made lighter than other materials.

[0072] The blocking layer 400 may be formed with a discharge slit 411 communicating with the vent hole H, similar to the cover part 300. The discharge slit 411 may be provided with a bridge 412.

[0073] The discharge slits 411 can be formed simultaneously by pressing the cover 300 and the blocking layer 400. In other words, in the conventional manufacturing process of the cover, additional bonding and punching processes are required for each component, and therefore, in the configuration of this embodiment, the bonding and punching processes for the cover 300 and the blocking layer 400 must be performed separately, which is a complicated process, increasing the takt time of the manufacturing process, raising manufacturing costs, and reducing productivity.

[0074] According to this embodiment, the blocking layer is foamed and bonded to the cover unit 300, and is thus integrally provided with the cover unit 300, eliminating the need for a separate bonding process. Since the adhesive layer between the layers of the existing cover unit can be omitted, the layer structure of the cover unit 300 is simplified, and the cover unit 300 is relatively resistant to flames or high temperatures, improving durability. The phenomenon of the adhesive layer melting due to flames or high heat causing the layer structure of the cover unit 300 itself to separate or peel off can be reduced.

[0075] Furthermore, since the cover part 300 is manufactured integrally with the cover part 300, the discharge slits 311, 411 of the cover part 300 and the blocking layer 400 can be simultaneously formed by a single integrated punching operation without a separate press process for forming the discharge slits 311, 411. This reduces the takt time in the module manufacturing process and reduces manufacturing costs, thereby improving productivity.

[0076] According to this embodiment, the cover 300 ensures fire resistance or heat resistance of the top and both side surfaces of the module case 200. In addition, the insulating layer 400 is foamed and attached to the cover 300, thereby blocking the entry and exit of flames when a thermal event occurs and minimizing heat transfer such as heat conduction and heat radiation, thereby suppressing flame propagation between modules and delaying cascading heat transfer as much as possible.

[0077] FIG. 6 is a diagram showing a modified example of the cover portion of FIG. 4, which is provided so as to cover the upper surface of the module case, and FIG. 7 is a diagram showing a modified example of the cover portion of FIG.

[0078] 6, as a modified example of the cover unit 300, the cover unit 300a may be provided to cover only the upper surface of the module case 200. The cover unit 300a may be provided as a flat plate type corresponding to the area of ​​the upper plate of the module case 200. Also, in this embodiment, the cover unit 300a does not have a second cover member 320 covering both side surfaces of the module case 200, and the cover unit 300a may be disposed only on the upper surface of the module case 200. Also, the barrier layer 400 may be provided on the bottom wall of the cover unit 300a.

[0079] 7, as a modified example of the barrier layer 400, the cover unit 300 includes a first cover member 310 and a second cover member 320. The barrier layer 400 may be provided not only on the first cover member 310 but also on the inner wall of the second cover member 320. That is, the barrier layer 400 may be coupled to both the inner wall of the first cover member 310 covering the top surface of the module case 200 and the inner wall of the cover unit 300 consisting of a pair of second cover members 320 covering both side surfaces in the length direction of the module case 200. According to this modified example, the flame barrier performance and heat transfer efficiency may be relatively improved compared to the above-described embodiment.

[0080] In this modified example, when the battery module 10 and the battery pack 1 (see FIG. 11) have different sizes, any one of the embodiments can be applied as needed.

[0081] In this way, the blocking layer 400 is foamed and bonded to the cover parts 300, 300a, so that when a thermal event occurs, the ingress and egress of flames is blocked and heat transfer such as heat conduction and heat radiation is minimized, thereby suppressing flame propagation between modules and delaying chain heat transfer as much as possible.

[0082] In addition, according to this embodiment, the blocking layer 400 is integrally bonded to the cover part 300a in a foamed state, so that the adhesive layer between the layered structure of the existing cover part 300 can be omitted, thereby simplifying the layered structure of the cover part 300a and improving its durability by being relatively resistant to flames or high temperatures.

[0083] In addition, it is possible to eliminate the additional bonding and punching processes required for each part in the manufacturing process of the existing flame-blocking cover, thereby shortening the takt time in the module manufacturing process and reducing manufacturing costs, thereby improving productivity.

[0084] Next, another embodiment of the battery module 10 of the present invention will be briefly described with reference to FIGS.

[0085] FIG. 8 is a diagram showing a cover portion of a battery module according to a second embodiment of the present invention, FIG. 9 is a diagram showing a cover portion of a battery module according to a third embodiment of the present invention, and FIG. 10 is a longitudinal cross-sectional view of a battery module according to a fourth embodiment of the present invention.

[0086] The same component numbers as in the previous drawings indicate the same components, and duplicated explanations of the same components will be omitted, with differences from the above-described embodiment being mainly explained.

[0087] 8, the cover unit 300b includes a first cover member 310 that covers an upper surface of the module case 200 and a pair of second cover members 320b that cover both side surfaces in the length direction of the module case 200, and the blocking layer 400 may be provided on an inner wall of the first cover member 310. In addition, the second cover member 320b may be provided with at least one concave-convex portion 330 that is recessed at regular intervals.

[0088] The uneven portion 330 may be provided in an area where the blocking layer 400 faces the second cover member 320b, and may be recessed at regular intervals in the thickness direction of the second cover member 320b.

[0089] According to this embodiment, the bonding strength between the cover part 300b and the barrier layer 400 can be further improved. That is, the barrier layer 400 is integrally bonded to the cover part 300b in a foamed state, and the edges of the barrier layer 400 are filled and hardened according to the shape of the uneven part 330, thereby allowing the barrier layer 400 to be more firmly bonded to the cover part 300b. The barrier layer 400 can be more integrally bonded to the cover part 300b. As a result, even if a thermal event occurs and the cover part 300b is exposed to a flame or high temperature, the phenomenon of the barrier layer 400 peeling off from the cover part 300b can be minimized. The layered structure of the cover part 300b including the barrier layer 400 is relatively more resistant to a flame or high temperature, thereby improving durability.

[0090] 9, the cover unit 300c of the battery module 10 according to the third embodiment includes a first cover member 310 that covers an upper surface of the module case 200, and a pair of second cover members 320c that cover both longitudinal side surfaces of the module case 200, and the barrier layer 400 may be provided on an inner wall of the first cover member 310. In addition, the second cover member 320c may be formed with a coupling sleeve 340 to which a jig 70 is detachably coupled.

[0091] Specifically, the barrier layer 400 is a foam layer attached to the inner wall of the cover portion 300c, and the foam layer needs to be controlled to form a predetermined thickness. Therefore, a separate guide or jig 70 may be required to control the thickness of the foam layer. Accordingly, the second cover member 320c may be provided with a coupling sleeve 340 that is spaced apart by the thickness of the barrier layer 400 and extends along the length of the cover portion 300c. After the jig 70 is coupled to the coupling sleeve 340 that extends along the length of the cover portion, the barrier layer 400 can be foamed in the gap formed between the jig 70 and the first cover member 310. In this case, the shape of the barrier layer 400 is guided, allowing the barrier layer 400 to be easily formed to a predetermined thickness. After the barrier layer 400 is coupled, the jig 70 can be removed.

[0092] Referring to FIG. 10, in the battery module 10 according to the fourth embodiment, the cell assembly 100 may be provided with a second barrier layer 420 that is arranged between each of the plurality of battery cells 110 and is foamed and attached.

[0093] In addition, the module case 200 may be provided with a third barrier layer 430 that is foamed and attached to the upper surface of the cell assembly 100 and the internal space of the module case 200. As a result, a foam layer made of polyurethane or silicone material covers each battery cell 110 inside the battery module, blocking the ingress and egress of flames and further minimizing heat transfer such as heat conduction and heat radiation. This improves the efficiency of suppressing flame spread between modules when a thermal event occurs, and can delay chain heat transfer as much as possible.

[0094] FIG. 11 is a diagram illustrating a battery pack according to one embodiment of the present invention, and FIG. 12 is a diagram illustrating a vehicle according to one embodiment of the present invention.

[0095] Referring to FIG. 11 , a battery pack 1 according to the present invention may include one or more battery modules 10 according to the present invention. In particular, to increase capacity and / or output, a battery pack 1 according to the present invention may include a plurality of battery modules 10 according to the present invention. In this case, the various configurations described above may be applied to each battery module 10. For example, each battery module 10 may include a cell assembly 100, a module case 200, and a cover unit 300, and the cover unit 300 may include a barrier layer 400. The barrier layer 400 may be formed of a foam layer made of polyurethane or silicone material and may easily block flame and heat transfer. Furthermore, a plurality of such battery modules 10 may be housed inside a pack case 50. Furthermore, in the case of a battery module 10 according to an embodiment of the present invention, even if other battery modules 10 are located in front or behind the battery module 10, heat transfer between the modules can be effectively prevented.

[0096] In addition to the battery module 10 and the pack case, the battery pack 1 according to the present invention may further include various other components, for example, battery pack components known at the time of filing of the present invention, such as a BMS (Battery Management System), bus bars, relays, current sensors, and fuses, in the internal space of the pack case.

[0097] 12, the battery module 10 according to the present invention or the battery pack 1 according to the present invention can be applied to a vehicle V such as an electric vehicle or a hybrid vehicle. That is, the vehicle V according to the present invention can include the battery module 10 according to the present invention or the battery pack 1 according to the present invention. Furthermore, the vehicle V according to the present invention can further include various other components included in the vehicle V, in addition to the battery module 10 or the battery pack 1. For example, the vehicle V according to the present invention can further include a vehicle body, a motor, a control device such as an ECU (electronic control unit), etc., in addition to the battery module 10 according to the present invention.

[0098] Furthermore, the battery module 10 according to the present invention or the battery pack 1 according to the present invention can be applied to an energy storage system (ESS). That is, the energy storage system according to the present invention can include the battery module 10 according to the present invention or the battery pack 1 according to the present invention.

[0099] Although the present invention has been described above using limited embodiments and drawings, it goes without saying that the present invention is not limited thereto, and that various modifications and variations can be made by a person having ordinary knowledge in the technical field to which the present invention pertains within the technical spirit of the present invention and the equivalent scope of the claims set forth below.

[0100] Meanwhile, when terms indicating directions such as up, down, left, right, front, and back are used in this specification, it will be clear to those skilled in the art of the present invention that such terms are used for the convenience of explanation and may vary depending on the position of the object in question, the position of the observer, etc. [Explanation of symbols]

[0101] 1: Battery pack 10: Battery module 100: Cell assembly 110: Battery cell 200: Module case 210: Case body H: Vent hole 220: End plate 300, 300a, 300b, 300c: Cover part 310: First cover member 311: Discharge slit 320, 320b, 320c: second cover member 330: Uneven part 340: coupling sleeve 350: Adhesive layer 400:Isolation layer V: Automobile

Claims

1. a cell assembly including a plurality of battery cells stacked on one another; a module case that houses the cell assembly in its internal space; a cover portion coupled to an outer surface of the module case, the cover portion having a barrier layer disposed between the cover portion and the module case, the barrier layer blocking the entrance and exit of a flame to reduce heat transfer; Including, The battery module, wherein the barrier layer is foamed and bonded to the cover portion, and is integrally provided with the cover portion.

2. The battery module according to claim 1 , wherein the insulating layer is provided on an inner wall of the cover portion on a side facing the cell assembly.

3. The battery module according to claim 2 , wherein the barrier layer is a foam layer foamed to a predetermined thickness and attached to the inner wall of the cover portion.

4. The battery module according to claim 2 , wherein the cover is provided to cover an upper surface of the module case, or to cover the upper surface of the module case and both side surfaces in a length direction of the module case.

5. The cover portion is a first cover member that covers an upper surface of the module case; The battery module according to claim 4 , further comprising: a pair of second cover members covering both side surfaces in the longitudinal direction of the module case.

6. The battery module according to claim 5 , wherein the barrier layer is provided on an inner wall of the first cover member or on inner walls of the first cover member and the second cover member.

7. The module case has one or more vent holes formed therein, The cover and the blocking layer are formed with exhaust slits communicating with the vent holes, The battery module according to claim 3 , wherein the discharge slit is formed simultaneously by pressing the cover portion and the blocking layer.

8. The battery module of claim 3 , wherein an adhesive layer is interposed between the barrier layer and the module case.

9. The battery module according to claim 3 , wherein the barrier layer comprises a polyurethane or silicone material.

10. The battery module according to claim 5 , wherein the second cover member is provided with at least one recessed portion formed at regular intervals.

11. 6. The battery module of claim 5, wherein the second cover member is provided with a connecting sleeve that is spaced apart by the thickness of the barrier layer, is provided along the length of the cover portion, and is detachably connected to a jig that guides the shape of the barrier layer when the barrier layer is foamed.

12. The battery module according to claim 3 , wherein the cell assembly is provided with a second insulating layer disposed between each of the plurality of battery cells and attached by foaming.

13. The battery module according to claim 12 , wherein the module case is provided with a third barrier layer that is foamed and attached to the upper surface of the cell assembly and the inner space of the module case.

14. A battery pack comprising the battery module according to any one of claims 1 to 13.

15. A motor vehicle comprising the battery pack of claim 14.

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