Battery module, battery pack and automobile including the same

Abstract

The present invention provides a battery module, a battery pack, and a vehicle including the same, which are configured to ensure structural stability even when a thermal event occurs. The battery module according to one aspect of the present invention includes a cell assembly including a plurality of battery cells, and a compression pad assembly disposed between the plurality of battery cells and having a heat shield with at least one hollow portion formed therein.

Description

[Technical Field]

[0001] The present invention relates to a battery module, a battery pack, and a vehicle including the same, and more particularly to a battery module, a battery pack, and a vehicle including the same, configured to ensure structural stability even when a thermal event occurs.This application claims priority to Korean Patent Application No. 10-2022-0050987 filed on April 25, 2022, and Korean Patent Application No. 10-2023-0009762 filed on January 25, 2023, the entire contents of which are incorporated herein by reference in their entirety. [Background technology]

[0002] In recent years, as the demand for portable electronic products such as laptops, video cameras, and mobile phones has grown rapidly and the development of electric vehicles, energy storage batteries, robots, satellites, and other products has progressed in earnest, active research has been conducted into high-performance secondary batteries that can be repeatedly charged and discharged.

[0003] Currently, commercially available secondary batteries include nickel-cadmium batteries, nickel-metal hydride batteries, nickel-zinc batteries, and lithium secondary batteries. Of these, lithium secondary batteries are attracting attention due to their advantages of being free to charge and discharge because they have almost no memory effect compared to nickel-based secondary batteries, a very low self-discharge rate, and a high energy density.

[0004] This type of lithium secondary battery mainly uses a lithium-based oxide and a carbon material as the positive and negative electrode active materials, respectively, and includes an electrode assembly in which a separator is sandwiched between positive and negative electrode plates coated with the positive and negative electrode active materials, and an exterior material that encapsulates the electrode assembly together with an electrolyte.

[0005] Generally, lithium secondary batteries are classified according to the shape of their exterior packaging into can-type secondary batteries in which an electrode assembly is housed in a metal can, and pouch-type secondary batteries in which an electrode assembly is housed in a pouch made of an aluminum laminate sheet.

[0006] Meanwhile, lithium secondary batteries are classified into can-type secondary batteries, in which an electrode assembly is housed in a metal can, and pouch-type secondary batteries, in which an electrode assembly is housed in an aluminum laminated sheet pouch, depending on the shape of the battery case. Can-type secondary batteries can also be classified into cylindrical batteries and prismatic batteries depending on the shape of the metal can.

[0007] The pouch of a pouch-type secondary battery can be broadly divided into a lower sheet and an upper sheet covering the lower sheet. The pouch accommodates an electrode assembly formed by stacking and / or winding a positive electrode, a negative electrode, and a separator. After accommodating the electrode assembly, the edges of the upper and lower sheets are sealed by heat sealing or the like. Furthermore, electrode tabs extending from each electrode are connected to electrode leads, and an insulating film may be attached to the electrode leads at the portions in contact with the sealing portions.

[0008] In this way, pouch-type secondary batteries can be flexibly adapted to various shapes. Another advantage of pouch-type secondary batteries is that they can achieve the same capacity with a smaller volume and mass.

[0009] Such lithium secondary batteries are used as battery modules or battery packs in which a plurality of battery cells are stacked or laminated by themselves or in cartridges to form a dense structure, and then electrically connected to each other.

[0010] One of the major concerns with such battery pack configurations is safety. Specifically, if a thermal event occurs in one of the multiple battery cells within a battery pack, it is necessary to suppress the propagation of that event to other battery cells. If heat propagation between battery cells is not properly suppressed, a thermal event may occur in other battery cells within the battery pack, potentially causing larger problems such as a fire or explosion of the battery pack. Furthermore, a fire or explosion of the battery pack could cause significant damage to surrounding people and property. Therefore, such battery packs require a configuration that can properly suppress the aforementioned thermal events. Summary of the Invention [Problem to be solved by the invention]

[0011] The present invention has been made in view of the above problems, and an object of the present invention is to provide a battery module, a battery pack, and a vehicle including the same that can ensure structural stability even when a thermal event occurs.

[0012] However, the technical problems that the present invention aims to solve are not limited to the problems described above, and other problems not mentioned will be clearly understood by those skilled in the art to which the invention pertains from the detailed description of the invention described below. [Means for solving the problem]

[0013] To achieve the above-mentioned object, according to one aspect of the present invention, a battery module includes: a cell assembly including a plurality of battery cells; and a compression pad assembly disposed between the plurality of battery cells and having a heat shield having at least one hollow portion formed therein.

[0014] Preferably, the compression pad assembly may be configured to come into close contact with opposing battery cells in a stacking direction of the plurality of battery cells.

[0015] Preferably, an air layer can be formed inside the at least one hollow portion.

[0016] Preferably, the heat shield further includes a body portion having the at least one hollow portion formed therein and disposed between the plurality of battery cells, and the body portion may be made of a metal material.

[0017] Preferably, the heat shield may further include a coating portion provided on both sides of the body portion in the stacking direction of the plurality of battery cells and configured to block flames caused by thermal runaway of the cell assembly.

[0018] Preferably, the compression pad assembly may further include a compression pad provided on the coating portion in a stacking direction of the plurality of battery cells and configured to come into close contact with an opposing battery cell in the stacking direction of the plurality of battery cells.

[0019] Preferably, the hollow portion may be provided inside the body portion and extend in at least one of a vertical direction and a stacking direction of the plurality of battery cells.

[0020] Preferably, the hollow portion may be configured to extend inside the body portion in a stacking direction of the plurality of battery cells and to abut against the coating portion.

[0021] Preferably, the battery module may further include a heat shield disposed between the compression pad and a battery cell facing the compression pad in the stacking direction of the plurality of battery cells.

[0022] In one preferred example, the hollow portion is contained as a single layer within the compression pad assembly.

[0023] In another preferred example, the hollow portion extends along the longitudinal direction of the battery cell, there are a plurality of hollow portions, and the hollow portions are spaced apart from each other and included inside the compression pad assembly.

[0024] In yet another preferred example, the hollow portions have a regular arrangement with their sizes and intervals controlled.

[0025] In yet another preferred example, the coating portion includes a ceramic coating layer made of only inorganic materials and not containing any organic substances.

[0026] A battery pack according to another aspect of the present invention includes at least one battery module according to the above-described aspect of the present invention.

[0027] Furthermore, a vehicle according to yet another aspect of the present invention includes at least one battery pack according to the other aspect of the present invention described above. [Effects of the Invention]

[0028] According to this embodiment of the present invention, a compression pad assembly having a heat insulating material therein is disposed between the battery cells, which can delay the spread of fire to the battery cells adjacent to the battery cell where the thermal runaway phenomenon occurs, thereby enhancing the structural stability of the battery module.

[0029] Furthermore, by providing a hollow portion inside the compression pad assembly to prevent heat transfer, the compression pad assembly can be configured with a compact structure that can delay the spread of flames without increasing its size compared to conventional methods.

[0030] In accordance with the present invention, a compression pad assembly can be used to inhibit and slow the progression of thermal runaway transient events within or between unit modules.

[0031] According to the present invention, even if thermal runaway, fire, explosion, etc. occurs in some battery cells in one battery module, this does not spread to other adjacent battery modules. Therefore, a chain reaction of thermal runaway, fire, or explosion among multiple battery cells does not occur, and secondary thermal runaway, secondary fire, explosion, etc. does not occur.

[0032] Therefore, according to the present invention, even if thermal runaway, fire, or explosion occurs in one of the plurality of battery cells, the thermal runaway, fire, or explosion cannot spread to other adjacent battery cells. Therefore, it is possible to provide a battery module with improved safety against thermal runaway, fire, explosion, etc., i.e., improved thermal safety, and a battery pack and a vehicle including the same.

[0033] In addition to the above, various other effects can be achieved by various embodiments of the present invention. Such various effects of the present invention will be described in more detail in the sections of each embodiment, and explanations of effects that can be easily understood by those skilled in the art will be omitted.

[0034] The drawings attached to this specification illustrate preferred embodiments of the present invention and serve to further understand the technical concepts of the present invention as well as the content of the invention, and therefore the present invention should not be interpreted as being limited to only the matters depicted in the drawings. [Brief explanation of the drawings]

[0035] [Figure 1] 1 is a diagram illustrating a battery module according to an embodiment of the present invention. [Figure 2] FIG. 2 is a detailed side view of a portion of the battery module of FIG. 1. [Figure 3] 3 is a diagram showing the overall shape of a compression pad assembly provided in the battery module of FIG. 2. FIG. [Figure 4] FIG. 4 is a side view of the compression pad assembly of FIG. 3. [Figure 5]FIG. 5 is a partially exploded perspective view of the compression pad assembly of FIG. 4. [Figure 6] FIG. 5 illustrates the compression pad assembly of FIG. 4 blocking a flame caused by thermal runaway in the cell assembly. [Figure 7] FIG. 4 is a diagram showing a battery module according to a second embodiment of the present invention. [Figure 8] FIG. 10 is a diagram showing a battery module according to a third embodiment of the present invention. [Figure 9] FIG. 10 is a diagram showing a battery module according to a fourth embodiment of the present invention. [Figure 10] FIG. 10 is a diagram showing a battery module according to a fifth embodiment of the present invention. [Figure 11] FIG. 10 is a diagram showing a battery module according to a sixth embodiment of the present invention. [Figure 12] 1 is a schematic diagram illustrating a battery pack according to an embodiment of the present invention. [Figure 13] 1 is a schematic diagram illustrating a vehicle 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 words used in the specification and claims should not be construed as being limited to their ordinary or 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 explain the invention.

[0037] Therefore, it should be understood that the embodiments described in this specification and the configurations shown in the drawings are merely the most preferred 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 diagram showing a battery module 10 according to one embodiment of the present invention, FIG. 2 is a detailed side view of a portion of the battery module 10 of FIG. 1, FIG. 3 is a diagram showing the overall shape of a compression pad assembly 300 provided in the battery module 10 of FIG. 2, and FIG. 4 is a side view of the compression pad assembly 300 of FIG. 3.

[0039] In an embodiment of the present invention, the X-axis direction in the drawing may refer to the stacking direction of the battery cells 110 described later, the Y-axis direction may refer to the longitudinal direction of the battery cells 110 that is perpendicular to the X-axis direction on a horizontal plane (XY plane), and the Z-axis direction may refer to the up-down direction of the battery cells 110 that is perpendicular to both the X-axis direction and the Y-axis direction.

[0040] 1 to 4, a battery module 10 according to one embodiment of the present invention may include a cell assembly 100 and a compression pad assembly 300.

[0041] The cell assembly 100 may include a plurality of battery cells 110. Here, each battery cell 110 may refer to a secondary battery. Each of the battery cells 110 may be provided as a pouch-type battery cell, a cylindrical battery cell, or a prismatic battery cell. For example, each of the battery cells 110 may be a pouch-type battery cell. The battery cells 110 may be arranged to be stacked in one direction (X-axis direction).

[0042] The battery cells 110 may be plate-shaped battery cells having a large area in the YZ plane. In such a case, the cell assembly 100 may be an assembly of battery cells 110, which are pouch-shaped battery cells stacked with their wide surfaces facing each other. The cell assembly 100 may be an assembly in which the battery cells 110 are arranged vertically (along the Z-axis direction) and stacked horizontally (along the X-axis direction). Pouch-shaped battery cells have the advantages of high energy density relative to their size and weight and ease of stacking. However, the battery cells 110 included in the battery module 10 according to the present invention are not limited to pouch-shaped battery cells, and various types of secondary batteries known at the time of filing may be used.

[0043] When the battery cell 110 is a pouch-type battery cell, the battery cell 110 may be realized in a form including an electrode assembly, a pouch, an electrode lead, and an insulating film (sealing tape).

[0044] Although not shown, the electrode assembly has a structure in which separators are interposed between positive and negative electrode plates that are alternately stacked, and preferably, separators are located on both outermost sides for insulation.

[0045] The positive electrode plate includes a positive electrode current collector and a positive electrode active material layer coated on one side thereof, and a positive electrode uncoated region where the positive electrode active material is not coated is formed at one end, and this positive electrode uncoated region functions as a positive electrode tab.

[0046] The negative electrode plate includes a negative electrode current collector and a negative electrode active material layer coated on one or both sides of the negative electrode current collector. One end of the negative electrode current collector has a negative electrode uncoated region where the negative electrode active material is not coated. This negative electrode uncoated region functions as a negative electrode tab.

[0047] In addition, the separator may be made of a porous material to be interposed between the positive electrode plate and the negative electrode plate to prevent direct contact between the electrode plates having different polarities and to allow ions to move between the positive electrode plate and the negative electrode plate via an electrolyte.

[0048] The pouch may include two regions: a housing portion that houses the electrode assembly; and a sealing portion that extends circumferentially around the housing portion and seals the pouch by being heat-sealed with the electrode lead pulled out to the outside.

[0049] The electrode leads are a pair, and are connected to the positive and negative electrode tabs of the electrode assembly, respectively, and are drawn out to the outside of the pouch. The pair of electrode leads may face each other and have a structure in which they protrude from one end and the other end of the battery cell 110, respectively. For example, the electrode leads may protrude from both ends of the battery cell 110 in the longitudinal direction.

[0050] The compression pad assembly 300 may be disposed between a plurality of battery cells 110. Such a compression pad assembly 300 may be disposed between all of the battery cells 110, or may be disposed only between some of the battery cells 110. For example, the compression pad assembly 300 may be a plate-shaped member that stands vertically (along the Z-axis direction) and has a wide surface in the YZ plane, and may be disposed between the battery cells 110 facing the wide surface of the battery cells 110.

[0051] In one embodiment, the compression pad assembly 300 may be configured to be disposed between a plurality of battery cells 110 to suppress swelling that may occur in the cell assembly 100. To this end, the compression pad assembly 300 may partially include an elastic material such as a contractible sponge.

[0052] Meanwhile, in the battery module 10 of the present invention, an event such as a thermal runaway phenomenon may occur in a specific battery cell 110 in the cell assembly 100. In this case, if a flame or spark occurs due to the thermal runaway phenomenon occurring in a specific battery cell 110, there is a risk that the flame or spark may spread to other battery cells 110 adjacent to the specific battery cell 110.

[0053] To solve this problem, the compression pad assembly 300 of the present invention may include a heat shield 310 having at least one hollow portion S formed therein. In this case, the hollow portion S may be provided with a heat insulating material to prevent heat transfer to the battery cells 110 arranged on both sides of the compression pad assembly 300. With this configuration, the compression pad assembly 300 can delay the spread of a fire that occurs in a specific battery cell 110. Meanwhile, the heat insulating material will be described in more detail in the related description below.

[0054] According to this embodiment of the present invention, the compression pad assembly 300 having a heat insulating material therein is disposed between the battery cells 110, which can delay the spread of fire from the battery cell 110 where a thermal runaway phenomenon occurs to the adjacent battery cells 110. This can enhance the structural stability of the battery module 10.

[0055] Furthermore, by providing a hollow portion S inside the compression pad assembly 300 to prevent heat transfer, the compression pad assembly 300 can be configured with a compact structure that can delay the spread of flames without increasing its size compared to conventional methods.

[0056] Meanwhile, the battery module 10 may further include a module case 500. The module case 500 may accommodate the cell assemblies 100 and the compression pad assemblies 300 therein. To this end, the module case 500 may be provided with an internal accommodation space for accommodating the cell assemblies 100 and the compression pad assemblies 300 therein. The module case 500 may include a monoframe, which is a rectangular tubular body having openings on both longitudinal sides of the battery cells 110, and end frames coupled to the openings of the monoframe. The monoframe has a very simple structure and has a suitable space and shape for accommodating the cell assemblies 100 therein. The monoframe is easy to handle because the cell assemblies 100 can be easily inserted through the openings. Furthermore, the battery module 10 can be easily assembled by simply closing the openings with the end frames. Therefore, a battery pack including the battery module 10 has a simple and compact structure without being complicated or occupying a large space. Furthermore, the battery module 10 can be easily assembled, resulting in excellent processability. As another example, the module case 500 may include a U-shaped frame having a bottom and two side walls surrounding the bottom and both sides of the cell assembly 100, end plates coupled to the front and rear of the U-shaped frame, and an upper plate coupled to the top of the U-shaped frame. Such a module case 500 reliably secures the battery cells 110 without using components such as a cell cartridge. Because the conventional cell cartridge does not have to sandwich the edges of the battery cells to secure them, the design flexibility of the entire battery module is increased, and the conventional problem of shocks and vibrations being transmitted to the edges of the battery cells when the edges of the battery cells are sandwiched inside the cell cartridge is resolved. A battery module including such a module case 500 and a battery pack including the same effectively protect the battery cells 110 from external vibrations, making them advantageous for use in automobiles and other vehicles that are frequently exposed to external vibrations.On the other hand, in a structure in which battery cells are stacked in a cell cartridge-type component, the presence of the cell cartridge-type component results in little cooling, or the cooling action occurs only in the surface direction of the battery cell, and cooling is not performed well in the height direction of the battery module. In the battery module 10 according to an embodiment of the present invention, cooling is performed smoothly even in the height direction of the battery module 10 (Z-axis direction).

[0057] The above-mentioned compression pad assembly 300 will now be described in more detail.

[0058] 1 to 4 again, the compression pad assembly 300 may be configured to closely contact the opposing battery cell 110 in the stacking direction of the plurality of battery cells. Therefore, the compression pad assembly 300 may be configured to be compressed when the opposing battery cell 110 expands, thereby effectively suppressing swelling that may occur in the cell assembly 100.

[0059] Furthermore, because the compression pad assembly 300 is in close contact with the opposing battery cell 110, a fire generated by a specific battery cell 110 does not spread to other parts of the battery module 10 (e.g., the internal space of the module case 500), and can be reliably blocked by the hollow portion S of the heat shield 310 provided in the compression pad assembly 300. In one embodiment, the size of the surface of the compression pad assembly 300 facing the battery cell 110 may be formed to correspond to the size of the side surface of the battery cell 110 in the stacking direction.

[0060] According to this embodiment of the present invention, the spread of flames within the battery module due to swelling and thermal runaway phenomena that may occur in the cell assembly 100 can be more effectively suppressed.

[0061] Furthermore, an air layer may be formed inside the at least one hollow portion S. This air layer can function as a heat insulating material that can prevent heat transfer to the battery cells 110 arranged on both sides of the compression pad assembly 300. That is, the hollow portion S is not filled with a separate refrigerant or additional components. The high heat insulating properties of the air layer are utilized without requiring a separate refrigerant circulation means or additional components. The hollow portion S is not intended for cooling, but rather to block thermal transfer. As a result, even if there is a temperature change in some battery cells 110 within the battery module 10, heat transfer to the outside is blocked, and as a result, heat transfer to adjacent battery cells 110 is blocked, preventing the occurrence of a chain reaction thermal event and improving the safety of the battery module 10.

[0062] According to this embodiment of the present invention, a hollow portion S is formed inside the compression pad assembly 300, and an air layer is formed inside the hollow portion S to prevent heat transfer, thereby eliminating the need for a liquid or solid insulating material, and reducing the manufacturing cost and overall weight of the compression pad assembly 300.

[0063] Referring again to FIGS. 1 to 4, the heat shield 310 may further include a body portion 312 .

[0064] The body portion 312 has at least one hollow portion S formed therein and can be disposed between a plurality of battery cells 110.

[0065] The body part 312 may also be made of a metal material. In this case, the body part 312 may function as a main frame to maintain the overall structure of the compression pad assembly 300. As an example, the body part 312 may be made of, but is not limited to, aluminum (Al) or an aluminum alloy. Furthermore, the body part 312 may be made of a flame-retardant metal. By making the body part 312 of aluminum (Al) or an aluminum alloy, it is possible to obtain a body part 312 that is strong, lightweight, heat-resistant, and can reliably block the propagation of flames.

[0066] According to this embodiment of the present invention, the main frame of the compression pad assembly 300 is constructed using a body portion 312 made of a flame-retardant metal material. This allows the compression pad assembly 300 to maintain relatively stable structural stability even in the event of a fire caused by thermal runaway in a battery cell 110, compared to conventional structures made solely of PET, sponge, or the like. In other words, existing battery modules and battery packs have had a problem in which thermal runaway spreads between adjacent battery cells 110 or between adjacent battery modules due to heat conduction to the outside or inside. In other words, existing battery modules and battery packs have had a problem in which a fire spreads (transfers) to adjacent battery cells or battery modules in the event of an event such as thermal runaway propagation because they lack a structure to prevent heat conduction and radiation. The battery module 10 of the present invention includes a compression pad assembly 300 having a heat shield 310 between adjacent battery cells 110, thereby reliably preventing the transfer of a fire in the event of an event such as thermal runaway propagation.

[0067] Furthermore, the body part 312 of the present invention not only has a hollow part (S) inside for preventing heat transfer to the battery cells 110 arranged on both sides of the body part 312, but is also made of a flame-retardant metal material, so that it can more reliably delay the spread of a flame occurring in a specific battery cell 110 to other adjacent battery cells 110. In other words, the body part 312 of the present invention can minimize the risk of chain fires of the battery cells 110.

[0068] If the compression pad were made of only a material such as PET or sponge without the body 312, the compression pad would burn during heat transfer, causing a fire to spread within the battery module. According to the present invention, the flame-retardant body 312 is included, thereby preventing a fire from spreading within the battery module 10.

[0069] Furthermore, since the hollow portion S having an air layer is formed inside the metal body portion 312, the manufacturing cost and the overall weight of the compression pad assembly 300 can be reduced.

[0070] The hollow portion S may extend along the longitudinal direction of the battery cell 110. Therefore, the hollow portion S has a shape extending in a direction parallel to the pair of electrode leads. In this embodiment, the hollow portion S extends along the protruding direction of the electrode leads, which generate heat relatively more in each battery cell 110, and therefore has an excellent effect of blocking thermal transfer between each battery cell 110.

[0071] When there are multiple hollow portions S, the hollow portions S may be spaced apart from one another within the compression pad assembly 300. In particular, as shown in FIGS. 2 to 4, the hollow portions S may be included as a single layer within the compression pad assembly 300. To further increase the energy density of the battery module 10, it is necessary to reduce the thickness of the compression pad assembly 300. Since including multiple hollow portions S as multiple layers while maintaining the necessary strength of the compression pad assembly 300 requires increasing the thickness of the body portion 312, it is preferable to include the hollow portions S as a single layer.

[0072] In the illustrated example, the cross-sectional structure of the compression pad assembly 300 includes a single layer of rectangular hollow portions S in the middle of the body portion 312, with the shape and size of the hollow portions S and the spacing between the hollow portions S being constant. The shape, size, and spacing of the hollow portions S can be adjusted to suitably prevent heat transfer by making the volume occupied by the hollow portions S as large as possible while maintaining the rigidity of the body portion 312.

[0073] To include hollow portions S in the metal body portion 312, the body portion 312 can be extrusion-manufactured. By adding protrusions that allow the plate to be extruded while forming hollow portions to a mold (metal die) that extrudes a metal plate, the hollow portions S can be formed inside the body portion 312 while extruding it into a plate shape. The hollow portions S have an elongated shape along the extrusion direction, and adjacent hollow portions S are formed side by side along the extrusion direction. Unlike metal foams, which have disordered hollow structures, the body portion 312 used in the present invention has a regularly arranged hollow structure. This allows the hollow portions S to be formed while controlling the size of the hollow portions S and the spacing between them, enabling precise control and management of the insulation effect.

[0074] When the body portion 312 is extruded, the hollow portion S extends in one direction along the extrusion direction, and both ends are open, so that such a body portion 312 can be called a hollow metal material.

[0075] The size of the hollow portions S and the spacing between the hollow portions S can be on the order of several millimeters, which means that there are densely formed minute hollow portions S. For example, if the thickness D of the body portion 312 in the stacking direction of the battery cells 110 is 1.5 to 4 mm and the size of the hollow portions S and the spacing between the hollow portions S are 0.3 to 2 mm, the body portion 312 can be made thin and lightweight while still maintaining rigidity, and by including as many hollow portions S as possible in a given space, the heat insulating effect can be maximized.

[0076] To further increase the energy density of the battery module 10, it is necessary to reduce the thickness of the body portion 312. However, when extruding a thin hollow metal material, the amount of material drawn out is too small compared to the amount of material added. As the thickness of the hollow metal material decreases, the pressure applied to the extrusion increases, which can damage the extrusion mold. Furthermore, as the thickness of the hollow metal material decreases, the molded product may lose its shape or have an uneven thickness. Therefore, the size of the hollow portions S and the spacing between the hollow portions S can be determined by comprehensively considering these issues. By adjusting the parameters (variables) during extrusion manufacturing, the hollow portions S can be formed with extremely high density. This has the advantage of providing excellent thermal insulation.

[0077] Fig. 5 is a partially exploded perspective view of the compression pad assembly 300 of Fig. 4, and Fig. 6 is a diagram showing the compression pad assembly 300 of Fig. 4 blocking a flame caused by thermal runaway of the cell assembly 100. In this case, the flame caused by thermal runaway of the cell assembly 100 in Fig. 6 may be exemplarily indicated as "F."

[0078] 5 and 6, the heat shield 310 may further include a coating 314.

[0079] The coating portion 314 is provided on both sides of the body portion 312 in the stacking direction of the plurality of battery cells 110, and may be configured to block flames caused by thermal runaway of the cell assembly 100. As an example, the heat shield portion 310 may be provided in the form of a thermal barrier coating. For this purpose, a thermal barrier coating agent (e.g., an environmentally friendly coating agent) may be applied or attached to the heat shield portion 310.

[0080] As a preferred example, the coating portion 314 may be a ceramic coating layer made solely of inorganic materials, without including any organic substances. The ceramic coating layer is a fire-resistant coating. Conventional ceramic coatings are coatings made by adding ceramic as a partial additive to an organic material (e.g., fluororesin). In one embodiment of the present invention, an environmentally friendly, high-performance ceramic coating layer can be used because it is made primarily of ceramic and does not include any organic substances. The ceramic coating layer can be formed by applying a coating agent containing ceramic powder and then allowing it to harden naturally or at a low temperature of around 200°C. In other words, the heat shield 310 of the compression pad assembly 300 of the present invention includes a fire-resistant coating layer, which is an environmentally friendly ceramic coating layer that is applied and hardened.

[0081] The coating agent can be a slurry made by mixing fine ceramic powders such as alumina and silica with water and an inorganic dispersant. To enable the formation of a glassy substance, inorganic oxides (such as KO and BaO) can also be included. However, this slurry does not contain organic solvents or organic binders.

[0082] The inclusion of organic solvents and organic binders results in poor heat resistance and significant deterioration over time after coating formation. In the present invention, such a slurry-like coating agent can be applied to the surface of the body portion 312 and cured to form a ceramic coating layer. The application can be performed by any method, such as dip coating, spin coating, spray coating, or brushing. Such a slurry-like coating agent can be directly applied to metal to achieve low-temperature fusion, is environmentally friendly, harmless to humans, and has excellent corrosion resistance, wear resistance, and adhesion.

[0083] The ceramic coating layer can block flames of 1000°C or higher, thereby blocking the spread of flames to adjacent battery modules. Furthermore, the ceramic coating layer can further improve the durability of the compression pad assembly 300 and, ultimately, the battery module 10.

[0084] According to this embodiment of the present invention, the spread of the flame can be more effectively delayed by, first, the coating portion 314 for blocking the flame caused by thermal runaway of the cell assembly 100, and, second, the body portion 312 and the hollow portion S provided inside the body portion 312. Furthermore, this embodiment can further ensure the structural stability of the battery module 10.

[0085] Additionally, the compression pad assembly 300 may further include a compression pad 320 .

[0086] The compression pad 320 may be provided on the coating portion 314 in the stacking direction of the plurality of battery cells 110. For example, the compression pad 320 may be bonded to the surface of the coating portion 314 by an adhesive. For example, the compression pad 320 may be made of an elastic material such as a sponge.

[0087] Furthermore, the compression pad 320 may be configured to come into close contact with the opposing battery cell 110 in the stacking direction of the plurality of battery cells 110. As a result, the compression pad 320 may be configured to suppress a swelling phenomenon that may occur in the cell assembly 100.

[0088] Specifically, the compression pad 320 may include a first pad 322 and a second pad 324 .

[0089] The first pad 322 may be provided on a surface of the coating portion 314 provided on one side of the body portion 312 in the stacking direction of the plurality of battery cells 110. The first pad 322 may be configured to be in close contact with the battery cell 110 facing it in the stacking direction of the plurality of battery cells 110. In this case, the size of the surface of the first pad 322 facing the battery cell 110 may be formed to correspond to the size of the side of the battery cell 110 in the stacking direction. In addition, the first pad 322 may be compressed when the opposing battery cell 110 expands.

[0090] The second pad 324 may be provided on a surface of the coating portion 314 provided on the other side of the body portion 312 in the stacking direction of the plurality of battery cells 110. The second pad 324 may be configured to be in close contact with the battery cell 110 facing it in the stacking direction of the plurality of battery cells 110. In this case, the size of the surface of the second pad 324 facing the battery cell 110 may be formed to correspond to the size of the side of the battery cell 110 in the stacking direction. In addition, the second pad 324 may be compressed when the opposing battery cell 110 expands.

[0091] According to this embodiment of the present invention, the spread of flames due to thermal runaway of the cell assembly 100 can be delayed and swelling that may occur in the cell assembly 100 can be suppressed, thereby further ensuring the structural stability of the battery module 10.

[0092] While existing compression pads made solely of materials such as PET or sponge have a thickness of approximately 3-4 mm, the compression pad assembly 300 of the present invention maintains an overall thickness of approximately 3-4 mm while exhibiting superior effectiveness in preventing chain reactions of heat transfer compared to conventional methods. For example, the first pad 322 and the second pad 324 may each have a thickness of approximately 0.5 mm, and the heat shield 310, including the coating portion 314 and the body portion 312, may have a thickness of approximately 2-3 mm, resulting in an overall thickness of approximately 3-4 mm for the compression pad assembly 300. In this case, the size of the hollow portion S in the stacking direction of the battery cells 110 may be approximately 1 mm. Here, the thickness and size are variable. However, the size of the hollow portion S is very small compared to the external size of the battery module 10, which can reach several hundred mm by several hundred mm. It should be understood that this is a different dimension from the scale required when forming a flow path in the module case itself.

[0093] FIG. 7 is a diagram showing a battery module 11 according to a second embodiment of the present invention, FIG. 8 is a diagram showing a battery module 12 according to a third embodiment of the present invention, and FIG. 9 is a diagram showing a battery module 13 according to a fourth embodiment of the present invention.

[0094] The battery modules 11, 12, and 13 according to the second to fourth embodiments of the present invention, which will be described below with reference to Figures 7 to 9, are identical or similar to the battery module 10 of the above-mentioned embodiment. Therefore, redundant descriptions of configurations that are substantially identical or similar to the battery module 10 of the above-mentioned embodiment will be omitted, and the following description will focus on the differences from the above-mentioned embodiment.

[0095] 7 to 9, the hollow portion S provided inside the body portion 312 may extend inside the body portion 312 in at least one of the vertical direction and the stacking direction of the plurality of battery cells 110.

[0096] 7, the hollow portion S may be provided inside the body portion 312 and extend in the vertical direction of the plurality of battery cells 110. In other words, the size of the hollow portion S in the vertical direction may be larger than that of the hollow portion S shown in FIGS.

[0097] 8, the hollow portion S may extend in the stacking direction of the plurality of battery cells 110 inside the body portion 312. In other words, the size of the hollow portion S in the stacking direction of the battery cells 110 may be larger than that of the hollow portion S shown in FIGS.

[0098] 9, the hollow portion S may be provided inside the body portion 312 to extend in both the vertical direction and the stacking direction of the plurality of battery cells 110.

[0099] In the battery modules 11, 12, and 13 according to the second to fourth embodiments of the present invention, the volume of the hollow portion S having an air layer formed therein can be made larger, thereby more reliably diffusing a flame caused by thermal runaway of the cell assembly 100.

[0100] FIG. 10 is a diagram showing a battery module 14 according to a fifth embodiment of the present invention.

[0101] Since the battery module 14 according to this embodiment is similar to the battery module 10 according to the above-described embodiment, redundant descriptions of configurations that are substantially identical or similar to those of the above-described embodiment will be omitted, and the following description will focus on the differences from the above-described embodiment.

[0102] According to the battery module 14 shown in FIG. 10, the hollow portion S provided inside the body portion 312 can be configured to extend inside the body portion 312 in the stacking direction of the multiple battery cells 110 and abut against the coating portion 314.

[0103] In the battery module 14 according to this embodiment, the hollow portion S having an air layer formed therein is configured to abut against the coating portion 314, so that heat transfer to the metal body portion 312 can be minimized.

[0104] That is, although the body portion 312 has flame retardancy as described above, it is made of a metal material and may therefore transfer heat to adjacent battery cells 110. Therefore, in the battery module 14 according to this embodiment, the hollow portion S is configured to extend in the stacking direction of the multiple battery cells 110 and abut against the coating portion 314, thereby minimizing heat transfer to the body portion 312. Therefore, it is possible to more reliably delay the spread of a flame that occurs in a specific battery cell 110 to other adjacent battery cells 110.

[0105] FIG. 11 is a diagram showing a battery module 15 according to a sixth embodiment of the present invention.

[0106] Since the battery module 15 according to this embodiment is similar to the battery module 10 according to the above-described embodiment, redundant descriptions of configurations that are substantially identical or similar to those of the above-described embodiment will be omitted, and the following description will focus on the differences from the above-described embodiment.

[0107] The battery module 15 shown in FIG. 11 may further include a heat shield 700.

[0108] The heat shield 700 may be disposed between the compression pad 320 and the battery cell 110 facing the compression pad 320 in the stacking direction of the plurality of battery cells 110 .

[0109] Such a heat shield 700 may be configured to block flames caused by thermal runaway of the cell assembly 100. As an example, the heat shield 700 may be provided in the form of a thermal barrier coating. As in the above-described embodiment, a thermal barrier coating (e.g., an environmentally friendly coating) may be applied or deposited on the heat shield 700.

[0110] In the case of the battery module 15 according to this embodiment, the spread of the flame can be delayed more effectively by, first, the heat shield 700 for blocking the flame caused by thermal runaway of the cell assemblies 100, second, the coating portion 314, and third, the body portion 312 and the hollow portion S provided inside the body portion 312. Furthermore, this embodiment configuration can further stably maintain the structural stability of the battery module 10.

[0111] Furthermore, since the heat shield 700 is disposed between the compression pad 320, which is made of a material vulnerable to fire, and the battery cell 110, the heat shield 700 can further ensure the structural stability of the compression pad assembly 300 by delaying the spread of fire to the compression pad 320.

[0112] Meanwhile, a battery pack including the battery module 10 according to the present invention can be configured. That is, the battery pack according to the present invention can include at least one battery module according to the present invention.

[0113] Furthermore, the battery pack according to the present invention can be applied to automobiles such as electric vehicles, that is, an automobile according to the present invention can include at least one battery pack according to the present invention.

[0114] The above-described battery module and a battery pack including the same can be applied to various devices. Typical examples of such devices include transportation means such as electric bicycles, electric vehicles, and hybrid vehicles, but the present invention is not limited thereto. Such a battery pack is suitable for use as a battery pack for electric vehicles. It can also be used as an energy source for an energy storage system (ESS).

[0115] FIG. 12 is a schematic diagram showing a battery pack according to one embodiment of the present invention, and FIG. 13 is a schematic diagram showing a vehicle according to one embodiment of the present invention.

[0116] 12 and 13, a battery pack 800 according to an embodiment of the present invention may include at least one battery module 10 according to the above-described embodiments and a pack case 810 that packages the at least one battery module 10. The battery pack 800 may also include at least one of battery modules 11, 12, 13, 14, and 15 instead of the battery module 10.

[0117] In addition to the battery module 10 and pack case 810, the battery pack 800 according to the present invention may further include various devices for controlling the charging and discharging of the battery module 10, such as a battery management system (BMS), a current sensor, a fuse, etc. The BMS estimates the state of the cells in the battery pack 800 and manages the battery pack 800 using the estimated state information. For example, the BMS estimates and manages state information of the battery pack 800, such as the state of charge (SOC), state of health (SOH), maximum allowable input / output power, and output voltage of the battery pack 800. The state information can also be used to control the charging or discharging of the battery pack 800 and to estimate when the battery pack 800 should be replaced.

[0118] The battery modules 10 are substantially rectangular parallelepiped-shaped and are arranged in an orderly fashion inside a pack case 810, and each battery module 10 is connected so as to ensure the power required for the automobile 900 to run.

[0119] The pack case 810 is a rectangular box that is a container for fixing and accommodating the battery modules 10. The pack case 810 can be disposed at a predetermined position inside the automobile 900.

[0120] Preferably, the automobile 900 may be an electric automobile. The battery pack 800 can be used as an electric energy source that provides driving force to a motor of the electric automobile to drive the automobile 900. In this case, the battery pack 800 has a high nominal voltage of 100 V or more.

[0121] The battery pack 800 can be charged or discharged by an inverter in response to the driving of the motor and / or the internal combustion engine. The battery pack 800 can be charged by a regenerative charging device coupled to a brake. The battery pack 800 is electrically connected to the motor of the automobile 900 via an inverter. It goes without saying that the battery pack 800 may also be provided outside the automobile in other devices, equipment, and facilities such as an energy storage system (ESS) that uses a secondary battery.

[0122] Thus, the battery pack 800 according to this embodiment and devices, instruments, and equipment equipped with the battery pack 800, such as the automobile 900, include the battery module 10 described above, and it is possible to realize a battery pack 800 having all the advantages of the battery module 10 described above, and devices, instruments, and equipment, such as the automobile 900 equipped with this battery pack 800.

[0123] Although the present invention has been described above using limited embodiments and drawings, the present invention is not limited to these, and it goes without saying 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 scope of equivalents of the claims.

[0124] Meanwhile, although directional terms such as up, down, left, right, front, and back can be used in this specification, it will be obvious to those skilled in the art of the present invention that these terms are used merely 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]

[0125] 10, 11, 12, 13, 14, 15 Battery Module 100 Cell Assembly 110 battery cells 300 Compression Pad Assembly 310 Heat shielding section S Hollow part 312 Body 314 Coating Department 320 Compression Pad 700 Heat shielding material

Claims

1. a cell assembly including a plurality of battery cells; a compression pad assembly disposed between the plurality of battery cells and having a heat shield with a plurality of hollow portions formed therein; Including, the plurality of hollow portions extend in the longitudinal direction of the battery cell at intervals from one another, penetrate the heat shield, and are provided in a single layer inside the compression pad assembly; The compression pad assembly is configured to be in close contact with a battery cell that faces the battery cell in a stacking direction of the plurality of battery cells.

2. Inside the plurality of hollow portions, The battery module according to claim 1 , wherein an air layer is formed.

3. The heat shielding portion is a body portion having the plurality of hollow portions formed therein and disposed between the plurality of battery cells; The body portion is The battery module according to claim 1 , wherein the battery module is made of a metal material.

4. The heat shielding portion is 4. The battery module according to claim 3, further comprising a coating portion provided on both sides of the body portion in the stacking direction of the plurality of battery cells, the coating portion being configured to block a flame caused by thermal runaway of the cell assembly.

5. The compression pad assembly includes:

5. The battery module according to claim 4, further comprising a compression pad provided on the coating portion in a stacking direction of the plurality of battery cells and configured to come into close contact with an opposing battery cell in the stacking direction of the plurality of battery cells.

6. The plurality of hollow portions are The battery module according to claim 4 , wherein the coating portion is configured to extend in the stacking direction of the plurality of battery cells inside the body portion and to abut against the coating portion.

7. The battery module according to claim 5 , further comprising: a heat shielding member disposed between the compression pad and a battery cell facing the compression pad in a stacking direction of the plurality of battery cells.

8. The battery module according to claim 1 , wherein the plurality of hollow portions are regularly arranged with controlled sizes and intervals.

9. The battery module according to claim 4 , wherein the coating portion includes a ceramic coating layer made of only inorganic material and not containing organic material.

10. A battery pack comprising at least one battery module according to any one of claims 1 to 9.

11. A motor vehicle comprising at least one battery pack according to claim 10.

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