Battery module, Battery pack and vehicle including the same

Abstract

The present invention relates to a battery module characterized by comprising: a cell assembly including a plurality of battery cells; a module case configured to accommodate the cell assembly; and a thermally conductive adhesive interposed between the cell assembly and the module case, configured such that a heat transfer inhibition section in which at least a portion undergoes thermal decomposition at a reference temperature is gradually expanded.

Description

Technology Field

[0001] The present invention relates to a battery module, a battery pack including the same, and an automobile. Background Technology

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

[0003] Currently, widely used types of rechargeable batteries include lithium-ion batteries, lithium-polymer batteries, nickel-cadmium batteries, nickel-hydrogen batteries, and nickel-zinc batteries. When high output voltage is required, multiple battery cells are connected in series to form a battery module or battery pack. Additionally, to increase charge / discharge capacity, multiple battery cells are connected in parallel to form a battery module or battery pack.

[0004] When configuring a battery pack by connecting multiple battery cells in series or parallel, it is common practice to first construct a battery module containing at least one battery cell, and then use this at least one battery module to add other components to form a battery pack or battery rack. Alternatively, recently, battery packs in the form of a "Cell-to-Pack," in which multiple battery cells are directly housed in a pack housing without modularization, are also being manufactured.

[0005] Meanwhile, in the case of a conventional battery module, a thermally conductive adhesive (such as thermal resin) for cooling the battery cells or fixing the cell assembly may be applied to one side of a cell assembly in which these battery cells are stacked. Additionally, in a battery pack containing multiple battery modules, a thermally conductive adhesive may be applied to the outer surface of each battery module.

[0006] In the case of such conventional battery modules or battery packs, various problems may arise when thermal events occur. For instance, if a thermal runway occurs within a battery module, heat generated from a trigger cell can be transferred to adjacent battery cells or modules through a thermally conductive adhesive. Consequently, there may be a problem in which thermal runway propagation is triggered between battery cells or modules.

[0007] Therefore, there is a need to develop a structure that can prevent the propagation of thermal runaway by suppressing the transfer of heat between battery cells or battery modules through a thermally conductive adhesive when thermal runaway occurs within a battery module. The problem to be solved

[0008] Accordingly, the present invention was devised to solve the above-mentioned problems and aims to provide a battery module that effectively prevents or delays the propagation of thermal runaway between modules by minimizing the direction of high-temperature gases or flames generated in battery cells toward adjacent battery modules in the event of an abnormal situation in the battery module.

[0009] However, the problems that the present invention aims to solve are not limited to those described above, and other unmentioned problems will be clearly understood by those skilled in the art from the description of the invention below. means of solving the problem

[0010] To solve the above problem, a battery module according to one embodiment of the present invention comprises: a cell assembly including a plurality of battery cells; a module case configured to accommodate the cell assembly; and a thermally conductive adhesive interposed between the cell assembly and the module case, configured such that a heat transfer inhibition section in which at least a portion undergoes thermal decomposition at a reference temperature is gradually expanded.

[0011] The battery cell is provided as a pouch-type battery cell and is configured to be stacked face-to-face such that the side portion where the electrode lead is not drawn faces downward, and the thermally conductive adhesive may be provided at the bottom of the cell assembly.

[0012] The above module case may be provided with a venting hole on its upper surface configured to allow venting gas generated from the battery cell to be discharged.

[0013] The above thermally conductive adhesive is used as a heat transfer path for cooling the battery cell in a normal state, and when a thermal event occurs, the heat transfer suppression section can be expanded to block the heat transfer path between adjacent battery cells.

[0014] The above heat transfer suppression section can be configured to gradually extend along the stacking direction of the plurality of battery cells.

[0015] The above heat transfer suppression section may be configured to gradually extend along the length direction of the battery cell.

[0016] Each of the above battery cells is equipped with an electrode lead, and the heat transfer suppression section may be configured to gradually expand along the direction in which the electrode lead is drawn out.

[0017] In addition, the present invention provides a battery pack characterized by including a battery module according to the present invention.

[0018] A battery pack according to one embodiment of the present invention may further include a pack case configured to accommodate a plurality of battery modules, and a pack thermally conductive adhesive interposed between the module case and the pack case, configured such that a heat transfer inhibition section in which at least a portion undergoes thermal decomposition at a reference temperature is gradually expanded.

[0019] The above heat transfer suppression section may be configured to gradually expand along the arrangement direction of a plurality of battery modules.

[0020] The above-described pack case has a plurality of receiving spaces configured to accommodate a plurality of the battery modules, and the pack thermally conductive adhesive may be provided within each of the receiving spaces.

[0021] The heat transfer inhibition section within any of the above-mentioned receiving spaces may be configured to extend to an adjacent other receiving space.

[0022] And, the present invention provides an automobile characterized by including a battery pack according to the present invention. Effects of the invention

[0023] According to one embodiment of the present invention, in a battery module or battery pack containing a plurality of battery cells in a stacked form, cooling of the battery cells or battery modules can be smoothly performed under normal conditions. In addition, when thermal runaway occurs in a battery module, the heat transfer path to adjacent battery cells or battery modules can be blocked.

[0024] In particular, according to one embodiment of the present invention, the propagation of thermal runaway between modules can be effectively prevented or delayed by minimizing the direction of high-temperature gases or flames generated in battery cells toward adjacent battery modules in the event of an abnormal situation of a battery module. This ensures the safety and reliability of the battery module.

[0025] Accordingly, according to these aspects of the present invention, events such as fire or explosion caused by thermal runaway phenomena in a battery pack including a plurality of battery modules or a device equipped with them can be prevented or delayed.

[0026] In addition to the above, the present invention may have various other effects, which are described in each embodiment, or effects that can be easily inferred by those skilled in the art, etc., will be omitted. Brief explanation of the drawing

[0027] The following drawings attached to this specification illustrate preferred embodiments of the present invention and serve to further enhance understanding of the technical concept of the present invention together with the detailed description of the invention provided below; therefore, the present invention should not be interpreted as being limited only to the matters described in such drawings. FIG. 1 is an overall perspective view of a battery module according to one embodiment of the present invention. FIG. 2 is an exploded perspective view of a battery module according to one embodiment of the present invention. FIG. 3 is a cross-sectional view of a battery module according to an embodiment of the present invention. For example, FIG. 3 may be a drawing showing the cross-section I-I' of FIG. 1. FIG. 4 is a diagram illustrating a thermally conductive adhesive that undergoes thermal decomposition in at least a portion when a thermal event occurs in a battery module according to one embodiment of the present invention. FIG. 5 is a diagram illustrating a heat transfer suppression section that gradually expands when a thermal event occurs in a battery module according to an embodiment of the present invention. FIG. 6 is a diagram illustrating a thermally conductive adhesive that undergoes thermal decomposition in at least a portion when a thermal event occurs in a battery module according to another embodiment of the present invention. FIG. 7 is a diagram illustrating a heat transfer suppression section that gradually expands when a thermal event occurs in a battery module according to another embodiment of the present invention. FIG. 8 is an exploded perspective view schematically showing the configuration of a battery pack according to one embodiment of the present invention. FIG. 9 is a cross-sectional view of a battery pack according to one embodiment of the present invention. FIG. 10 is a diagram illustrating a heat transfer suppression section that gradually expands when a thermal event occurs in a battery pack according to one embodiment of the present invention. FIG. 11 is a schematic perspective view of an automobile according to one embodiment of the present invention. Specific details for implementing the invention

[0028] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. Prior to this, terms and words used in this specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings, but should be interpreted in a meaning and concept consistent with the technical spirit of the present invention, based on the principle that the inventor can appropriately define the concept of the terms to best describe his invention.

[0029] Therefore, the embodiments described in this specification and the configurations illustrated in the drawings are merely the most preferred embodiments of the present invention and do not represent all of the technical ideas of the present invention; thus, it should be understood that various equivalents and modifications that can replace them may exist at the time of filing this application.

[0030] In addition, the present invention includes various embodiments. For each embodiment, redundant descriptions of substantially identical or similar configurations are omitted, and the focus is on the differences.

[0031] Meanwhile, although terms indicating directions such as up, down, left, right, front, and back may be used in the present invention, these terms are used merely for convenience of explanation and may vary depending on the position of the object or the position of the observer, as is obvious to those skilled in the art of the present invention.

[0032] For example, in an embodiment of the present invention, the X-axis direction shown in the drawing may mean the left-right direction, i.e., the stacking direction of the battery cell; the Y-axis direction may mean the front-back direction perpendicular to the X-axis direction on the horizontal plane (XY plane), i.e., the length direction of the battery cell; and the Z-axis direction may mean the up-down direction (vertical direction) perpendicular to both the X-axis direction and the Y-axis direction, i.e., the height direction of the battery cell.

[0034] FIG. 1 is an overall perspective view of a battery module according to an embodiment of the present invention, FIG. 2 is an exploded perspective view of a battery module according to an embodiment of the present invention, and FIG. 3 is a cross-sectional view of a battery module according to an embodiment of the present invention. For example, FIG. 3 may be a diagram showing the cross-section I-I' of FIG. 1. In addition, FIG. 4 is a diagram illustrating a thermally conductive adhesive in which at least a portion is thermally decomposed when a thermal event occurs in a battery module according to an embodiment of the present invention. And FIG. 5 is a diagram illustrating a heat transfer suppression section that gradually expands when a thermal event occurs in a battery module according to an embodiment of the present invention.

[0035] Referring to FIGS. 1 to 5, the battery module (10) according to the present invention comprises a cell assembly (100), a module case (200), and a thermally conductive adhesive (300).

[0036] A cell assembly (100) may comprise one or more battery cells (110), particularly a plurality of battery cells (110). Here, each battery cell (110) may refer to a single secondary battery itself or may refer to a battery group in which multiple secondary batteries are assembled. In this specification, the description is based on the assumption that the battery cell (110) represents a single secondary battery.

[0037] A plurality of battery cells (110) may include an electrode assembly, a cell case that accommodates the electrode assembly, and an electrode lead (111) that is connected to the electrode assembly and extends outward from the cell case to function as an electrode terminal.

[0038] The electrode leads (111) may be provided as a pair, and the pair of electrode leads (111) may be drawn out at both ends of the battery cell (110), that is, in the longitudinal direction (±Y direction). At this time, the pair of electrode leads (111) may be a positive lead and a negative lead. If necessary, the battery cell (110) may have a form in which the two electrode leads (111) are located only at one end in the Y-axis direction, for example, at the end in the +Y-axis direction.

[0039] At this time, the shape of the battery case can be configured in various ways, and depending on the shape of the battery case, the battery cell (110) can be classified into pouch-type cells, cylindrical-type cells, prismatic-type cells, etc. Since the types of such battery cells (110) are widely known at the time of filing the present invention, a detailed description is omitted. The present invention is applicable to all types of secondary batteries known at the time of filing the present invention and is not limited to a specific type of secondary battery.

[0040] In the cell assembly (100), a plurality of battery cells (110) may be configured in a stacked form in at least one direction. For example, as shown in FIG. 2, a plurality of battery cells (110) may be stacked in a horizontal direction, particularly in the left-right direction (X-axis direction). And, a plurality of battery cells (110) provided in the cell assembly (100) may be electrically connected to each other in series and / or parallel through a bus bar (not shown), etc.

[0041] Meanwhile, referring to FIG. 2, the module case (200) may be configured to accommodate a cell assembly (100). Specifically, the module case (200) may be configured to have a receiving space formed therein and to accommodate a cell assembly (100) in the receiving space.

[0042] For example, the module case (200) may have a case body (210), a top plate (220), and an end plate (230) to define a receiving space. Then, a cell assembly (100) may be positioned in such a defined receiving space. The module case (200) may be composed of at least partially metal and / or plastic material.

[0043] At least some of the plate-like members constituting the module case (200) may be configured in a form that is integrated with one another. For example, the module case (200) may have a case body (210) in the form of a U-frame in which a bottom plate (210a), a left plate, and a right plate (210b) are integrated with one another, as shown in FIG. 2, and the top plate (220) and end plate (230) may be configured to cover or seal the top, front, and rear of the case body (210).

[0044] At this time, various fastening methods such as welding, bonding, bolting, and hooks may be used to secure the connection between the top plate (220) and the end plate (230) and the case body (210).

[0045] Alternatively, the module case (200) may be manufactured in a monoframe form in which the top plate (220) and the case body (210) are integrated with each other. Alternatively, the module case (200) may be configured in a form in which each plate is manufactured separately and then joined and fixed through welding or the like. However, the present invention is not limited to a specific material or form of such module case (200).

[0046] The above thermally conductive adhesive (300) may be interposed between the cell assembly (100) and the module case (200). For example, referring to the illustration in FIG. 2, the thermally conductive adhesive (300) may be provided on one side of the cell assembly (100), such as between the bottom of the cell assembly (100) and the bottom surface (210a) of the module case (200).

[0047] Meanwhile, in the various drawings of this specification, the configuration in which the thermally conductive adhesive (300) is located on the lower side of the battery module (10) has been described primarily, but the thermally conductive adhesive (300) may be located on other sides, such as the upper side of the battery module (10). Additionally, the thermally conductive adhesive (300) may be located on two or more sides of the battery module (10). For example, the thermally conductive adhesive (300) may be applied to the upper side and the lower side of the cell assembly (100), respectively.

[0048] The thermally conductive adhesive (300) can be configured to transfer heat between the cell assembly (100) and the module case (200). The battery cell (110) may generate heat during use, and if this heat is not properly discharged, the performance of the battery cell (110) cannot be reliably guaranteed, and in severe cases, it may lead to thermal runaway, ignition, explosion, etc. of the battery cell. In this regard, the heat generated from the battery cell (110) needs to be properly discharged to the outside through the module case (200). At this time, the thermally conductive adhesive (300) can ensure stable cooling performance for the battery module (10) by ensuring good heat transfer between the battery cell (110) and the module case (200).

[0049] The thermally conductive adhesive (300) may be provided with a material capable of transferring heat. In particular, the thermally conductive adhesive (300) may be made of a resin material, and in this case, the thermally conductive adhesive (300) may be referred to as a thermal resin. The thermally conductive adhesive (300) may include at least one material among various materials, such as urethane, silicone, and epoxy. The thermally conductive adhesive (300) may be expressed by other terms such as TIM (Thermal Interface Material) or potting resin, and as the material of the thermally conductive adhesive (300) of the battery module (10) according to the present invention, various thermally conductive adhesives or TIMs known at the time of filing the present invention may be used.

[0050] A thermally conductive adhesive (300) may be interposed between the entire battery cell (110) provided in the cell assembly (100) and the module case (200). That is, the thermally conductive adhesive (300) may be configured to be in direct contact with all the battery cells (110) included in the cell assembly (100). According to this embodiment of the present invention, heat dissipation through the thermally conductive adhesive (300) can be achieved for all the battery cells (110) included in the battery module (10). Accordingly, the overall cooling performance of the battery module (10) can be further improved.

[0051] And, the thermally conductive adhesive (300) may be configured to fix the cell assembly (100) to the module case (200). To this end, the thermally conductive adhesive (300) may have an adhesive component. For example, as shown in FIG. 3, when the thermally conductive adhesive (300) is located at the bottom of the cell assembly (100), the thermally conductive adhesive (300) may adhesively fix the bottom side of the cell assembly (100) to the bottom surface (210a) of the module case (200).

[0052] This thermally conductive adhesive (300) can be applied to the lower surface (210a) of the module case (200) before the cell assembly (100) is accommodated in the module case (200), and then cured over time.

[0053] Meanwhile, referring to FIGS. 4 and 5, the thermally conductive adhesive (300) may be configured such that at least a portion of it decomposes by heat at a reference temperature. That is, the thermally conductive adhesive (300) may decompose by heat when a thermal event occurs in a battery cell (110). Thermal decomposition refers to a reaction in which weak bonds are broken when molecules are activated by applying heat to a material. When the thermally conductive adhesive (300), which is made of an organic compound such as thermal resin, decomposes by heat, the thermal conductivity may be reduced.

[0054] At this time, the reference temperature may refer to the temperature at which a thermal event occurs in the battery cell (110) and the thermally conductive adhesive (300) begins to decompose. For example, the reference temperature may be set higher than the normal operating temperature of the battery cell (110). The normal operating temperature of the battery cell (110) may refer to the temperature when no thermal event occurs in the battery cell (110). Additionally, the normal operating temperature of the battery cell (110) may refer to the temperature at which the battery cell (110) is repeatedly charged and discharged under normal circumstances. For example, the normal operating temperature of the battery cell (110) may be approximately 60 degrees. Additionally, the reference temperature may be set lower than the self-heating temperature of the battery cell (110).

[0055] The portion where the thermally conductive adhesive (300) undergoes thermal decomposition can be defined as a heat transfer inhibition section (S). Referring to FIG. 5, this heat transfer inhibition section (S) can be configured to gradually expand. That is, the portion where the thermally conductive adhesive (300) undergoes thermal decomposition and its thermal conductivity decreases can be gradually expanded. The length or volume of the thermally decomposing thermally conductive adhesive (300) can gradually increase. The heat transfer inhibition section (S) can be configured to start at the portion in contact with the battery cell (110) where the thermal event occurred and gradually expand to adjacent portions as heat is conducted to adjacent battery cells (110). The heat transfer inhibition section (S) can be extended along the horizontal direction in which the thermally conductive adhesive (300) is applied.

[0056] That is, the thermally conductive adhesive (300) is used as a heat transfer path for cooling the battery cell (110) in a normal state, and when a thermal event occurs, the heat transfer suppression section (S) is expanded to block the heat transfer path between adjacent battery cells (110).

[0057] In particular, as in the embodiment illustrated in FIG. 5, the heat transfer suppression section (S) can be configured to gradually extend along the stacking direction (X-axis direction) of a plurality of battery cells (110).

[0058] According to the above embodiment of the present invention, cooling of the cell assembly (100) can be carried out smoothly under normal conditions. In addition, when thermal runaway occurs in the battery module (10), the transfer of heat to adjacent battery cells (110) or battery modules (10) can be blocked through the thermally conductive adhesive (300).

[0059] Accordingly, according to the above embodiment of the present invention, high-temperature gas or flames generated in the battery cell (110) in the event of an abnormal situation of the battery module (10) are minimized from moving toward adjacent battery modules (10), thereby effectively preventing or delaying the propagation of thermal runaway within the battery module (10). As a result, the safety and reliability of the battery module (10) can be guaranteed.

[0060] In particular, as in the embodiment illustrated in FIG. 2, the battery cell (110) is provided as a pouch-type battery cell and may be configured to be stacked face-to-face such that the side portion (the side without a sealing portion) where the electrode lead (111) is not drawn out faces downward. At this time, each battery cell (110) may have the sealing portion facing forward and backward (Y-axis direction) and upward (+Z-axis direction), and the storage portion facing left and right (X-axis direction).

[0061] The thermally conductive adhesive (300) may be provided at the bottom of the cell assembly (100). That is, as in the embodiment shown in FIGS. 2 to 5, the thermally conductive adhesive (300) may be configured to be interposed only at the bottom of the cell assembly (100) to fix the bottom of the cell assembly (100).

[0062] Meanwhile, the module case (200) may be provided with a venting hole (H). The venting hole (H) may be configured to allow venting gas generated in the battery cell (110) to be discharged to the outside. One-way directional venting may be possible through the venting hole (H). Multiple venting holes (H) may be provided and may be arranged at regular intervals from each other in the horizontal direction (X-axis, Y-axis direction).

[0063] For example, as illustrated in FIGS. 1 to 5, a venting hole (H) may be formed on the upper surface of the module case (200). Thus, directional venting of the battery module (10) upward through the venting hole (H) formed on the upper surface of the module case (200) may be possible.

[0064] According to the above embodiment of the present invention, in a situation where one of the battery cells (110) undergoes thermal runaway and generates gas, etc., the gas, etc. can be rapidly vented in a specific direction. As a result, the venting gas or flame generated inside the battery module (10) can be smoothly discharged to the outside of the battery module (10), thereby effectively preventing or delaying the propagation of thermal runaway between battery modules (10).

[0066] FIG. 6 is a diagram illustrating a thermally conductive adhesive in which at least a portion is thermally decomposed when a thermal event occurs in a battery module according to another embodiment of the present invention, and FIG. 7 is a diagram illustrating a heat transfer suppression section that gradually expands when a thermal event occurs in a battery module according to another embodiment of the present invention.

[0067] Referring to FIGS. 6 and 7, the heat transfer suppression section (S) can be configured to gradually extend along the longitudinal direction (Y-axis direction) of the battery cell (110). The heat transfer suppression section (S) can extend along the longitudinal direction of the battery cell (110) as well as the stacking direction of the battery cell (110). In particular, the heat transfer suppression section (S) can be configured to gradually extend along the direction in which the electrode lead (111) is drawn out.

[0068] When a thermal event occurs in a battery cell (110) and a venting gas or flame is generated, it is highly likely to be ejected toward the sealing portion of the battery cell (110) where the electrode lead (111) is located. According to the above embodiment of the present invention, as shown in the embodiment illustrated in FIGS. 6 and 7, even if a thermal event occurs in the battery cell (110) and a flame or spark is generated in the electrode lead (111) provided on one side of the battery cell (110), the heat of the gas or flame can be suppressed or blocked from being transferred to the electrode lead (111) provided on the other side as the heat transfer suppression section (S) is extended along the direction in which the electrode lead (111) is drawn out.

[0069] Accordingly, it is possible to prevent thermal damage or structural collapse to components located at both ends of the battery module (10), such as end plates (230) or adjacent components of a busbar frame (not shown). Additionally, it is possible to minimize heat propagation to adjacent battery modules (10) caused by flames discharged to the outside through the end plates (230).

[0071] FIG. 8 is an exploded perspective view schematically showing the configuration of a battery pack according to one embodiment of the present invention, FIG. 9 is a cross-sectional view of a battery pack according to one embodiment of the present invention, and FIG. 10 is a drawing explaining a heat transfer suppression section that gradually expands when a thermal event occurs in a battery pack according to one embodiment of the present invention.

[0072] Referring to FIGS. 8 to 10, a battery pack (1) according to one embodiment of the present invention may include one or more battery modules (10) according to one embodiment of the present invention as described above.

[0073] Additionally, a battery pack (1) according to one embodiment of the present invention may further include a pack case (2). The pack case (2) may be configured to accommodate a plurality of battery modules (10). The pack case (2) may have a plurality of receiving spaces (PS) configured to accommodate each of the plurality of battery modules (10). The plurality of battery modules (10) may be arranged along a plurality of columns and rows inside the pack case (2). The pack case (2) may be configured to accommodate a plurality of battery modules (10).

[0074] The pack case (2) may be formed in the shape of a rectangular box. More specifically, the pack case (2) may include a base frame (21), a side frame (22), a cross beam (23), and a pack lid (24).

[0075] The base frame (21) can form the lower surface of the pack case (2) and can be provided in the shape of a roughly square plate. Additionally, the base frame (21) can be provided with a flat upper surface so that a plurality of battery modules (10) can be stably seated.

[0076] The above side frame (22) may extend upward from each corner of the base frame (21). The side frame (22) may be provided with a plurality of unit walls to surround the battery module (10). More specifically, the side frame (22) may form the side of the pack case (2) by including a rear wall located at the +Y direction side end of the base frame (21), a right wall located at the -X direction side end, a front wall located at the -Y direction side end, and a left wall located at the +X direction side end.

[0077] The cross beam (23) may be configured to partition between a plurality of battery modules (10). That is, the cross beam (23) may be configured to partition a plurality of receiving spaces (PS). For example, the cross beam (23) may be formed in the shape of a partition wall extending long in the left-right direction and interposed between battery modules (10) arranged adjacently in the front-rear direction. Additionally, the cross beam (23) may be formed in the shape of a partition wall extending long in the front-rear direction and interposed between battery modules (10) arranged adjacently in the left-right direction.

[0078] The above pack lid (24) may be configured to cover the upper portion of a plurality of battery modules (10). The pack lid (24) may be provided to be coupled to the upper portion of the side frame (22) to form the upper surface of the pack case (2).

[0079] Additionally, although not shown in the drawing, the pack case (2) may be configured to accommodate components such as a Battery Management System (BMS), a current sensor, and a fuse for integrated control of charging and discharging of one or more battery cells (110) inside.

[0080] Meanwhile, a battery pack (1) according to one embodiment of the present invention may further include a pack thermal conductive adhesive (3). The pack thermal conductive adhesive (3) may have the same material as the thermal conductive adhesive (300), differing only in location. That is, the pack thermal conductive adhesive (3) may also be configured to transfer heat between the battery module (10) and the pack case (2) and to fix the battery module (10) to the pack case (2).

[0081] The pack thermal conductive adhesive (3) may be interposed between the module case (200) and the pack case (2). For example, referring to the illustration in FIGS. 8 to 10, the pack thermal conductive adhesive (3) may be provided between the lower surface (210a) of the battery module (10) and the base frame (21) of the pack case (2). That is, the thermal conductive adhesive (300) may be provided on the inside of the battery module (10), and the pack thermal conductive adhesive (3) may be provided on the outside of the battery module (10).

[0082] Additionally, the pack thermal conductive adhesive (3) may be provided within each receiving space (PS). That is, the pack thermal conductive adhesive (3) may be provided for each of the multiple battery modules (10). Accordingly, the pack thermal conductive adhesive (3) may be arranged along multiple columns and rows.

[0083] And, referring to FIG. 10, the pack thermally conductive adhesive (3) may be configured such that at least a portion of it decomposes at a reference temperature. Additionally, the pack thermally conductive adhesive (3) may be configured such that the heat transfer inhibition section (S) is gradually expanded. Accordingly, the section (S1, S2) may start at the battery module (10) where the thermal event occurred and gradually expand to the adjacent battery module (10) as heat is conducted to the adjacent battery module (10).

[0084] The heat transfer suppression sections (S1, S2) can be extended along the horizontal direction in which the pack thermally conductive adhesive (3) is applied. Additionally, the heat transfer suppression sections (S1, S2) can be configured to gradually extend along the arrangement direction of a plurality of battery modules (10). In particular, referring to the embodiment illustrated in FIG. 10, the heat transfer suppression sections (S1, S2) within a certain receiving space (PS1) can be configured to extend to an adjacent receiving space (PS2). That is, the heat transfer suppression sections (S1, S2) can extend beyond the cross beam (23) to another receiving space (PS).

[0085] More specifically, when a thermal event occurs in a battery cell (110) of a battery module (10A), heat can be sequentially transferred along a thermally conductive adhesive (300) interposed on the side of the battery cell (110), a pack thermally conductive adhesive (3) provided on the outside of the battery module (10A), a pack thermally conductive adhesive (3) provided on the outside of an adjacent battery module (10B), a thermally conductive adhesive (300) provided on the inside of an adjacent battery module (10B), and a battery cell (110) of the adjacent battery module (10B).

[0086] However, according to the above embodiment of the present invention, when a thermal event occurs in a battery cell (110) of a battery module (10A), a thermally conductive adhesive (300) interposed on the side of the battery cell (110) is thermally decomposed to form a heat transfer suppression section (S1, S2), and the heat transfer suppression section (S1, S2) can be gradually extended to the side of an adjacent battery module (10B).

[0087] Thus, according to the above embodiment of the present invention, cooling of the battery module (10) can be smoothly performed under normal conditions. In addition, when thermal runaway occurs in the battery module (10), the transfer of heat to an adjacent battery module (10) through the pack thermal conductive adhesive (3) can be blocked.

[0088] Accordingly, in the event of an abnormal situation in the battery module (10), the high-temperature gas or flame generated in the battery module (10) may be minimized from moving toward adjacent battery modules (10), thereby effectively preventing or delaying the propagation of thermal runaway within the battery pack (1). This ensures the safety and reliability of the battery pack (1).

[0090] FIG. 11 is a schematic perspective view of an automobile according to one embodiment of the present invention.

[0091] Referring to FIG. 11, a vehicle (V) according to one embodiment of the present invention may include one or more battery packs (1) according to one embodiment of the present invention. The vehicle (V) according to the present invention may be, for example, an electric vehicle, a hybrid vehicle, or a plug-in hybrid vehicle. The vehicle (V) may include a four-wheeled vehicle and a two-wheeled vehicle. The vehicle (V) may operate by receiving power from a battery pack (1) according to one embodiment of the present invention.

[0093] Although the present invention has been described above by limited embodiments and drawings, the present invention is not limited thereto, and it is obvious that various modifications and variations are possible within the scope of the technical spirit of the present invention and the equivalent scope of the claims described below by those skilled in the art to which the present invention belongs. Explanation of the symbols

[0094] V : Car 1 : Battery pack 2 : Pack Case 21 : Base frame 22 : Side frame 23: Cross Beam 24: Pack Lead PS: Accommodation space 3 : Pack thermally conductive adhesive 10: Battery Module 100 : Cell Assembly 110: Battery cell 111: Electrode Lead 200 : Module case H: Venting hole 210 : Case body 220 : Top Plate 230 : End plate 300: Thermally conductive adhesive S, S1, S2: Heat transfer inhibition zones

Claims

Claim 1 A battery module comprising: a cell assembly including a plurality of battery cells; a module case configured to accommodate the cell assembly; and a thermally conductive adhesive interposed between the cell assembly and the module case, configured such that a heat transfer inhibition section in which at least a portion undergoes thermal decomposition at a reference temperature is gradually expanded, wherein the thermally conductive adhesive is used as a heat transfer path for cooling the battery cells in a normal state, and is configured such that, upon the occurrence of a thermal event, the heat transfer inhibition section is expanded to block the heat transfer path between adjacent battery cells. Claim 2 A battery module according to claim 1, wherein the battery cell is provided as a pouch-type battery cell and is configured to be stacked face-to-face such that the side portion where the electrode lead is not drawn out faces downward, and the thermally conductive adhesive is provided at the bottom of the cell assembly. Claim 3 A battery module according to claim 1, wherein the module case is configured to have a venting hole on its upper surface to discharge venting gas generated from the battery cell. Claim 4 delete Claim 5 A battery module according to claim 1, characterized in that the heat transfer suppression section is configured to gradually expand along the stacking direction of the plurality of battery cells. Claim 6 A battery module according to claim 1, characterized in that the heat transfer suppression section is configured to gradually extend along the length direction of the battery cell. Claim 7 A battery module according to claim 1, wherein each battery cell is provided with an electrode lead, and the heat transfer suppression section is configured to gradually expand along the direction in which the electrode lead is drawn out. Claim 8 A battery pack comprising a battery module according to any one of paragraphs 1 through 3 and paragraphs 5 through 7. Claim 9 A battery pack according to claim 8, further comprising a pack case configured to accommodate a plurality of the above-mentioned battery modules, and a pack thermally conductive adhesive interposed between the module case and the pack case, configured such that a heat transfer inhibition section in which at least a portion undergoes thermal decomposition at a reference temperature is gradually expanded. Claim 10 A battery pack according to claim 9, characterized in that the heat transfer suppression section is configured to gradually expand along the arrangement direction of a plurality of battery modules. Claim 11 A battery pack according to claim 9, wherein the pack case has a plurality of receiving spaces configured to accommodate a plurality of battery modules, and the pack thermal conductive adhesive is provided within each of the receiving spaces. Claim 12 A battery pack according to claim 11, characterized in that the heat transfer inhibition section within any of the above-mentioned receiving spaces is configured to extend to an adjacent other of the above-mentioned receiving spaces. Claim 13 An automobile including a battery pack pursuant to paragraph 8.

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