Battery assembly and battery pack including same

Abstract

The battery assembly according to an embodiment of the present invention comprises: a battery cell stack in which a plurality of battery cells are stacked; a first resin layer applied on a first surface of the battery cell stack; a second resin layer applied on a second surface which is opposite to the first surface of the battery cell stack; a frame covering at least a portion of the battery cell stack and including a venting hole through which a venting gas is discharged; and an inlet and an outlet for circulating a refrigerant inside a housing.

Description

Battery assembly and battery pack including the same

[0001] Cross-citation with related application(s)

[0002] This application claims the benefit of priority based on Korean Patent Application No. 10-2024-0199638 filed on December 30, 2024, and all contents disclosed in the document of said Korean patent application are incorporated herein as part of this specification.

[0003] The present invention relates to a battery assembly and a battery pack including the same, and more specifically, to a battery assembly with improved thermal management and airtightness and a battery pack including the same.

[0004] In modern society, as the use of portable devices such as mobile phones, laptops, camcorders, and digital cameras has become commonplace, the development of technologies related to such mobile devices is becoming active. Furthermore, rechargeable secondary batteries are being utilized as power sources for electric vehicles (EVs), hybrid electric vehicles (HEVs), and plug-in hybrid electric vehicles (P-HEVs) as a solution to address air pollution caused by conventional gasoline vehicles using fossil fuels; consequently, the need for the development of secondary batteries is increasing.

[0005] Currently commercialized rechargeable batteries include nickel-cadmium, nickel-hydrogen, nickel-zinc, and lithium-ion batteries. Among these, lithium-ion batteries are gaining attention for their advantages, such as the ability to charge and discharge freely with almost no memory effect compared to nickel-based batteries, a very low self-discharge rate, and high energy density.

[0006] These lithium secondary batteries primarily use lithium-based oxides and carbon materials as the positive and negative active materials, respectively. The lithium secondary battery comprises an electrode assembly in which a positive plate and a negative plate, each coated with the positive and negative active materials, are arranged with a separator in between, and a battery case that seals and houses the electrode assembly together with an electrolyte.

[0007] Generally, lithium secondary batteries can be classified according to the shape of the casing into can-type secondary batteries, in which the electrode assembly is embedded in a metal can, and pouch-type secondary batteries, in which the electrode assembly is embedded in a pouch of aluminum laminate sheet.

[0008] In the case of secondary batteries used in small devices, 2 to 3 battery cells are arranged, whereas in the case of secondary batteries used in medium to large devices such as automobiles, a battery assembly in which multiple battery cells are electrically connected is used. In such a battery assembly, capacity and output are improved by connecting multiple battery cells in series or parallel to form a battery cell stack. In addition, one or more battery assemblies can be mounted together with various control and protection systems, such as a Battery Disconnect Unit (BDU), a Battery Management System (BMS), and a cooling system, to form a battery pack.

[0009] Medium to large battery assemblies, which utilize multiple connected battery cells, face the challenge of effectively managing the heat generated during charging and discharging. Inadequate thermal management can lead to temperature imbalances between cells, resulting in performance degradation, shortened lifespan, and even dangerous situations such as explosions. Consequently, there is a growing technical demand for ensuring gas ventilation and airtightness, along with effective thermal management within the battery assembly.

[0010] Currently commercialized battery assemblies have limitations, such as unclear separation between cooling and gas exhaust paths, or the potential for structural damage due to external shocks and vibrations. To address these issues, a new design is required that maximizes thermal management performance and effectively separates the gas exhaust and cooling paths. At the same time, a technical approach is needed to enhance the durability of the battery assembly and increase efficiency by simplifying the manufacturing and assembly processes.

[0011] To solve these problems, the present invention aims to provide a battery assembly and a battery pack including the same, which improves the thermal management, gas evacuation, airtightness, and structural stability of a battery cell stack.

[0012] The problem that the present invention aims to solve is to provide a battery assembly and a battery pack including the same that effectively manage heat by clearly separating the gas exhaust path and preventing interference with the cooling path during a thermal runaway situation occurring inside the battery assembly.

[0013] However, the problems that the embodiments of the present invention aim to solve are not limited to the problems described above and can be expanded in various ways within the scope of the technical ideas included in the present invention.

[0014] A battery assembly according to one embodiment of the present invention comprises: a battery cell stack having a plurality of battery cells stacked thereon; a first resin layer applied to a first surface of the battery cell stack; a second resin layer applied to a second surface located opposite to the first surface of the battery cell stack; a frame covering at least a portion of the battery cell stack and including a venting hole through which venting gas is discharged; and an inlet and an outlet for circulating a refrigerant into the housing.

[0015] The portion of the above frame where the venting hole is located can cover the second surface of the battery cell stack.

[0016] The second resin layer can be applied while avoiding the portion corresponding to the venting hole.

[0017] At least a portion of the second resin layer may be applied along the edge of the second surface of the battery cell laminate.

[0018] Due to the second resin layer, the refrigerant may not flow into the area between the portion of the frame where the venting hole is located and the second surface of the battery cell laminate.

[0019] The battery cell includes a sealing portion, and at least a portion of the sealing portion may be positioned to face the second surface of the battery cell stack.

[0020] The battery assembly may further include a pad located between the battery cell stacks and having a cooling hole formed therein through which the refrigerant flows.

[0021] At least a portion of the second resin layer may be applied to an area corresponding to the pad.

[0022] The battery assembly may further include a housing in which the battery cell stack and the frame are housed. A first opening may be provided in the housing that overlaps at least partially with the venting hole.

[0023] The above housing includes a second opening and a third opening that are open in directions facing each other, and end covers may be located at each of the second opening and the third opening.

[0024] The end cover may include a main body portion covering the second opening or the third opening; and an extension portion extending from the main body portion to cover the outer surface of the housing.

[0025] A sealant may be applied between the extension and the outer surface of the housing.

[0026] The battery assembly may further include a housing cover that covers at least a portion of the frame where the venting hole is located.

[0027] The above housing cover may include a venting slot through which venting gas is discharged.

[0028] The above venting slot may overlap with the above venting hole in at least a portion.

[0029] An adhesive may be applied between the above frame and the above housing cover.

[0030] It may further include a third resin layer applied between the above frame and the above housing cover.

[0031] The third resin layer can be applied while avoiding the portion corresponding to the venting hole.

[0032] The above housing cover may include a housing cover flange.

[0033] The battery assembly may further include a housing in which the battery cell stack and the frame are housed, and the housing may include a housing flange that is coupled to the housing cover flange.

[0034] The above housing cover flange and the above housing flange can be bolted together.

[0035] According to another embodiment of the present invention, a battery pack comprising the battery assembly is provided.

[0036] According to embodiments of the present invention, the cooling path and the gas exhaust path within the battery assembly are physically separated so that gas can be rapidly discharged to the outside in the event of thermal runaway. This reduces the risk of explosion caused by an increase in internal pressure and significantly improves the stability of the battery system.

[0037] The effects of the present invention are not limited to those mentioned above, and other unmentioned effects will be clearly understood by those skilled in the art from the description in the claims.

[0038] FIG. 1 is a perspective view showing a battery assembly according to one embodiment of the present invention.

[0039] Figure 2 is a plan view showing the battery assembly of Figure 1.

[0040] Figure 3 is a plan view showing the battery assembly of Figure 1 viewed from a different angle than that of Figure 2.

[0041] Figure 4 is an exploded perspective view showing the coupling relationship between the battery cell stack and the frame in the battery assembly of Figure 1.

[0042] FIG. 5 is an exploded perspective view showing the coupling relationship between the battery cell stack and the frame and housing of FIG. 4.

[0043] FIG. 6 is a plan view showing a part of a battery cell laminate having a second resin layer according to one embodiment of the present invention.

[0044] FIG. 7 is a plan view showing a part of a battery cell laminate having a first resin layer according to one embodiment of the present invention.

[0045] FIG. 8 is a perspective view showing a battery cell according to one embodiment of the present invention.

[0046] FIG. 9 is a partial perspective view showing a part of the battery cell of FIG. 8.

[0047] FIG. 10 is a cross-sectional view showing a cross-section cut along the cutting line A-A' of FIG. 3.

[0048] FIG. 11 is an exploded perspective view showing the coupling relationship between the housing and the end cover of FIG. 1.

[0049] FIG. 12 is an exploded perspective view showing a housing according to another embodiment of the present invention.

[0050] FIG. 13 is a perspective view showing an end cover according to one embodiment of the present invention.

[0051] FIG. 14 is a cross-sectional view showing a cross-section cut along the cutting line B-B' of FIG. 3.

[0052] FIG. 15 is an exploded perspective view showing a housing cover according to one embodiment of the present invention.

[0053] FIG. 16 is a perspective view showing a battery assembly according to another embodiment of the present invention.

[0054] FIG. 17 is a plan view showing the battery assembly of FIG. 16.

[0055] FIG. 18 is a plan view showing a battery assembly provided with an adhesive according to one embodiment of the present invention.

[0056] FIG. 19 is a plan view showing a battery assembly having a third resin layer according to one embodiment of the present invention.

[0057] FIG. 20 is a partially exploded perspective view showing a part of FIG. 15.

[0058] Hereinafter, various embodiments of the present invention will be described in detail with reference to the attached drawings so that those skilled in the art can easily implement the present invention. The present invention may be embodied in various different forms and is not limited to the embodiments described herein.

[0059] To clearly explain the present invention, parts unrelated to the explanation have been omitted, and the same reference numerals are used for identical or similar components throughout the specification.

[0060] Furthermore, the size and thickness of each component shown in the drawings are depicted arbitrarily for convenience of explanation, and thus the present invention is not necessarily limited to what is illustrated. Thicknesses have been enlarged in the drawings to clearly represent various layers and regions. Additionally, for convenience of explanation, the thickness of some layers and regions has been exaggerated in the drawings.

[0061] Furthermore, when a part such as a layer, membrane, region, or plate is said to be "on" or "on" another part, this includes not only the case where it is "directly above" the other part, but also the case where there is another part in between. Conversely, when a part is said to be "directly above" another part, it means that there is no other part in between. Also, saying that a part is "on" or "on" a reference part means that it is located above or below the reference part, and does not necessarily mean that it is located "on" or "on" facing the opposite direction of gravity.

[0062] Furthermore, throughout the specification, when a part is described as "including" a certain component, this means that, unless specifically stated otherwise, it does not exclude other components but may include additional components.

[0063] Additionally, throughout the specification, "planar" means when the subject part is viewed from above, and "cross-sectional" means when the cross-section obtained by vertically cutting the subject part is viewed from the side.

[0064] FIG. 1 is a perspective view showing a battery assembly (100) according to an embodiment of the present invention. FIG. 2 is a plan view showing the battery assembly (100) of FIG. 1. FIG. 3 is a plan view showing the battery assembly (100) of FIG. 1 viewed from an angle different from that of FIG. 2. FIG. 4 is an exploded perspective view showing the coupling relationship between the battery cell stack (120) and the frame (150) in the battery assembly (100) of FIG. 1. FIG. 5 is an exploded perspective view showing the coupling relationship between the battery cell stack (120) and the frame (150) of FIG. 4 and the housing (160). FIG. 6 is a plan view showing a part of a battery cell stack provided with a second resin layer (140) according to an embodiment of the present invention. FIG. 7 is a plan view showing a part of a battery cell stack provided with a first resin layer (130) according to an embodiment of the present invention.

[0065] Referring to FIGS. 1 to 7, a battery assembly (100) according to one embodiment of the present invention comprises: a battery cell stack (120) in which a plurality of battery cells (110) are stacked; a first resin layer (130) applied to a first surface (120a) of the battery cell stack (120); a second resin layer (140) applied to a second surface (120b) located opposite the first surface of the battery cell stack (120); a frame (150) covering at least a portion of the battery cell stack (120) and including a venting hole (151) through which venting gas is discharged; and an inlet (170) and an outlet (180) for circulating a refrigerant into a housing (160).

[0066] The battery cell (110) according to the present embodiment may be a battery cell of various shapes, for example, a pouch-type battery cell, a prismatic battery cell, or a cylindrical battery cell. For example, as shown in FIG. 4, the battery cell (110) according to the present embodiment may be a pouch-type battery cell (110). Although the following description describes a pouch-type battery cell (110), the battery cell according to the present embodiment is not limited thereto, and various types of battery cells may be applied.

[0067] In the battery assembly (100), multiple battery cells (110) may be provided. For example, multiple battery cells (110) may be stacked along one direction to form a battery cell stack (120) so that they can be electrically connected to each other. For example, multiple battery cells (110) may be stacked upright along a direction parallel to the X-axis of FIG. 4. The battery cells (110) may be stacked from one side of the frame (150) to another side of the frame (150) with one side of the battery cells (110) parallel to some of the side portions of the frame (150). Accordingly, electrode leads may protrude in a direction perpendicular to the direction in which the battery cells (110) are stacked. In the battery cell (110), one electrode lead may protrude toward the Y-axis direction of FIG. 4, and another electrode lead may protrude toward the -Y-axis direction of FIG. 4. If the battery cell (110) has electrode leads protruding in only one direction, the electrode leads may protrude in the Y-axis direction of FIG. 4 or the -Y-axis direction of FIG. 4.

[0068] Meanwhile, the battery assembly (100) according to the present embodiment may further include a housing (160) in which a battery cell stack (120) and a frame (150) are housed. The housing (160) is structured to cover the sides and bottom of the battery cell stack (120), thereby protecting the battery cell stack (120) from external impact and the environment. The side and bottom portions of the housing (160) may be integral as a single structure. Through this, the assembly and manufacturing process of the battery assembly (100) can be simplified, and the structural strength of the battery assembly (100) can be improved.

[0069] A first resin layer (130) is applied to a first surface (120a) of a battery cell stack (120) according to the present embodiment. For example, the first surface (120a) may be the lower surface of the battery cell stack (120). The first resin layer (130) may be applied between the first surface (120a) of the battery cell stack (120) and one surface of the frame (150). The first resin layer (130) may be in contact with the first surface (120a) of the battery cell stack (120) and one surface of the frame (150), respectively. The first resin layer (130) may serve to prevent a refrigerant from penetrating into the lower part of the battery cell stack (120). The first resin layer (130) may include silicone or a similar high-temperature resistant resin with excellent heat resistance and chemical resistance, and may be uniformly applied with a thickness of 0.1 mm or more and 0.5 mm or less.

[0070] A second resin layer (140) may be applied to a second surface (120b) located opposite to the first surface (120a) of the battery cell stack (120) according to the present embodiment. For example, the second surface (120b) may be the upper surface of the battery cell stack (120). The second resin layer (140) may be applied between the second surface (120b) of the battery cell stack (120) and the other surface of the frame (150). Additionally, the second resin layer (140) may be applied between the second surface (120b) of the battery cell stack (120) and the surface of the frame (150) where the venting hole (151) is provided. The second resin layer (140) may be in contact with the second surface (120b) of the battery cell stack (120) and the surface of the frame (150), respectively.

[0071] The second resin layer (140) can function to block the refrigerant from penetrating the venting gas discharge path from the top of the battery cell laminate (120). The second resin layer (140) can protect the gas discharge path by applying it only to the portion that does not directly overlap with the venting hole (151). The application method of the second resin layer (140) can form a pattern as needed to cover only specific portions, and can be designed to prevent the refrigerant from flowing into the venting gas discharge path while maintaining thermal resistance.

[0072] The frame (150) according to the present embodiment covers at least a portion of the battery cell stack (120) including a venting hole (151) and can provide a discharge path so that venting gas can be discharged to the outside. The frame (150) may be made of an aluminum alloy or a highly durable composite material, and the venting hole (151) may be located in the center of the frame (150) to facilitate gas discharge. The venting hole (151) may be designed with optimized location and size to rapidly discharge high-temperature gas generated during thermal runaway inside the battery assembly (100).

[0073] The housing (160) according to the present embodiment may be made of high-strength metal or high-strength plastic to withstand external impacts on the battery and provide a cooling path. Meanwhile, the housing (160) according to the present embodiment may be provided with a first opening (161). The first opening (161) may overlap at least partially with the venting hole (151). By providing the first opening (161) in the housing (160) and configuring it to overlap at least partially with the venting hole (151), the pressure inside the battery assembly (100) can be efficiently relieved. Venting gas generated from the battery cells (110) can pass through the venting hole (151) of the frame (150) and the first opening (161) of the housing (160) and be discharged to the outside of the battery assembly (100). This can provide a path through which high-temperature venting gas generated in a thermal runaway situation can be rapidly discharged to the outside without accumulating inside the housing (160). This structure can minimize the risk of explosion due to increased internal pressure and improve the stability of the battery system.

[0074] Additionally, the efficiency of the gas exhaust path can be increased by overlapping the first opening (161) and the venting hole (151). This can help shorten the gas exhaust time and restore the temperature balance inside the battery assembly (100) more quickly. In particular, the durability of the housing (160) is maintained and resistance to external shocks or vibrations can be increased by designing the periphery of the first opening (161) as a reinforced structure.

[0075] The first opening (161) according to the present embodiment may be located on the upper or side of the housing (160) and may be formed at a position overlapping with the venting hole (151) of the frame (150). The first opening (161) may have an appropriate thickness and shape so as not to reduce the structural strength inside the battery assembly (100). This allows for smooth gas discharge without deformation of the housing (160) even in a thermal runaway situation.

[0076] The battery cell stack (120) according to the present embodiment can be fixed inside the housing (160) and maintained stably. By stably fixing the battery cell stack (120) to the housing (160), positional changes of the battery cell (110) can be minimized. This protects the battery cell (110) from external shocks or vibrations, thereby preventing performance degradation of the battery assembly (100) and extending the lifespan of the battery cell (110). In addition, the fixing structure of the battery cell stack (120) is simple, which can reduce manufacturing costs and facilitate maintenance of the battery assembly (100).

[0077] For example, as described above, the first resin layer (130) may be in contact with the first surface (120a) of the battery cell stack (120) and one surface of the frame (150), respectively, and the second resin layer (140) may be in contact with the second surface (120b) of the battery cell stack (120) and the other surface of the frame (150), respectively. The battery cell stack (120) may be fixed to the frame (150) and stably maintained by the first resin layer (130) and the second resin layer (140). As described below, the battery assembly (100) according to the present embodiment may have a structure in which the battery cells (110) are directly cooled by a refrigerant. Therefore, a space is required for the refrigerant that directly cools the battery cells (110) to flow inside the housing (160). However, if the battery cells (110) are not fixed inside the housing (160) due to the space where the refrigerant flows, damage to the battery cells (110) may occur due to external impact or vibration. In this embodiment, the battery cell stack (120) can be fixed to the frame (150) by the first resin layer (130) and the second resin layer (140). Accordingly, the battery cells (110) can maintain their state even against external impact or vibration, thereby ensuring the structural safety of the battery assembly (100).

[0078] The refrigerant according to the present embodiment may be introduced into the housing (160) through the inlet (170) and then discharged outside the battery assembly (100) through the outlet (180). At this time, the refrigerant may be a fluid. For example, the refrigerant may be insulating oil or cooling water. However, since the refrigerant comes into direct contact with the battery cell stack (120), other electrical components, and terminal assembly, etc., within the battery assembly (100), it needs to be electrically insulated. Therefore, the refrigerant may be insulating oil as a material having insulating properties.

[0079] Specifically, the heat of the battery cell stack (120) can be effectively managed by circulating a refrigerant inside the housing (160). By circulating the refrigerant in direct contact with the battery cell stack (120), the heat of the battery cell (110) can be efficiently released.

[0080] In the first and second directions, which are opposite to and parallel to the direction in which the battery cells (110) are stacked, the inlet (170) may be positioned offset in the first direction from the center of the battery cell stack (120) in the direction in which the battery cells (110) are stacked. The outlet (180) may be positioned offset in the second direction from the center of the battery cell stack (120) in the direction in which the battery cells (110) are stacked. That is, it is preferable for the inlet (170) and the outlet (180) to be located on opposite sides of each other with respect to the direction in which the battery cells (110) are stacked. When the inlet (170) and the outlet (180) are arranged in this way, the refrigerant can flow through the entire space inside the housing (160) and evenly cool all the battery cells (110). If the inlet (170) and the outlet (180) are located together at the center of the battery cell stack (120) in the direction in which the battery cells (110) are stacked, the refrigerant will flow only to the central part, which has the least flow resistance, so the refrigerant will not flow well to the battery cells (110) located at the outer part of the battery cell stack (120). Consequently, this can lead to an imbalance in cooling within the battery assembly (100). For example, as shown in FIG. 4, the battery cells (110) can be stacked along a direction parallel to the X-axis. In this case, the first and second directions described above may be directions parallel to the X-axis. The inlet (170) may be positioned in the -X-axis direction relative to the center of the battery cell stack (120) in the direction in which the battery cells (110) are stacked, and the outlet (180) may be positioned in the X-axis direction relative to the center of the battery cell stack (120) along the axial direction.

[0081] By providing a first resin layer (130) and a second resin layer (140), the battery cell stack (120) can be designed to effectively manage heat and safely discharge gases generated under high-temperature conditions. That is, by using the first resin layer (130) and the second resin layer (140), the cooling path and the venting gas discharge path can be separated so that refrigerant does not penetrate the upper and lower surfaces of the battery cell stack (120). The first resin layer (130) and the second resin layer (140) are composed of a high-temperature resistant material so that they can maintain a stable physical structure even during a long-term thermal cycle, and the stability of the battery system can be ensured by blocking the inflow of refrigerant.

[0082] The venting hole (151) of the frame (150) according to the present embodiment can suppress the rise in internal pressure and reduce the risk of explosion by rapidly discharging high-temperature gas to the outside during thermal runaway. This prevents the thermal runaway from spreading to other battery cells (110), thereby increasing the safety of the entire battery assembly (100). The first opening (161) of the housing (160) overlaps with the venting hole (151) to provide a path for the discharged gas to be rapidly released to the outside, and a cooling path is maintained through the inlet (170) and outlet (180) to enable continuous cooling. The cooling fluid circulates around the battery cell stack (120) and lowers the temperature of the battery cell (110), thereby preventing performance degradation and shortening of lifespan due to high temperature.

[0083] As a result, the thermal management efficiency can be maximized through the clear separation of the cooling path and the venting gas exhaust path, and the stability and durability of the battery assembly (100) can be greatly improved.

[0084] Referring again to FIGS. 4 and FIGS. 5, the portion of the frame (150) where the venting hole (151) is located can cover the second surface (120b) of the battery cell stack (120).

[0085] Venting gas generated from the battery cell (110) can be discharged to the outside through the venting hole (151) of the frame (150). The battery assembly (100) may have a directional venting structure that induces the discharge of venting gas in the direction in which the venting hole (151) of the frame (150) is provided.

[0086] As described above, the first resin layer (130) according to the present embodiment may be applied to the first surface (120a) located opposite the second surface (120b) of the battery cell laminate (120). When the portion of the frame (150) where the venting hole (151) is located covers the second surface (120b), the first resin layer (130) and the portion of the frame (150) where the venting hole (151) is located may be located opposite each other with respect to the battery cell laminate (120). In the case of the first surface (120a), it is difficult for venting gas to be discharged from the battery cell (110) because the first resin layer (130) is present. The venting gas can be discharged in the direction where the second surface (120b) and the venting hole (151) of the frame (150) covering it are located, rather than the first surface (120a) which is blocked by the first resin layer (130). The first resin layer (130) according to the present embodiment can help implement a directional venting structure that induces the discharge of venting gas in the direction where the venting hole (151) of the frame (150) is provided.

[0087] The frame (150) according to the present embodiment stably supports the stacked structure of the battery cell stack (120) and, at the same time, can provide a venting gas discharge path capable of rapidly discharging gas generated in high-temperature situations such as thermal runaway. The frame (150) may be formed in a structure that covers a second surface (120b) of the battery cell stack (120), for example, a part of the upper surface of the battery cell stack (120), and a venting hole (151) is located in this cover portion so that gas can be rapidly discharged to the outside. The frame (150) may be made of a high-strength metal material, for example, aluminum alloy or high-strength stainless steel, so that it can be firmly maintained even against the expansion or impact of the battery cell (110). The venting hole (151) located in the frame is positioned to be in close contact with the second surface (120b) of the battery cell stack (120), and may be designed at an optimal position and size to smoothly discharge high-pressure gas when thermal runaway occurs.

[0088] The cover portion of the frame (150) covering the second side (120b) is open toward the top where gas is discharged, thereby allowing the venting hole (151) to align precisely with the gas discharge hole, making it easy to discharge gas. Additionally, the frame (150) stably covers the second side (120b), so that even if the battery cell stack (120) expands due to heat or pressure, the gas discharge path remains unobstructed and the frame remains fixed.

[0089] By positioning the venting hole (151) of the frame (150) to cover the second surface (120b) of the battery cell stack (120), high-temperature gas generated inside the battery cell (110) can be rapidly discharged to the outside. This ensures that a clear gas discharge path is secured even if thermal runaway occurs, and prevents a rapid increase in internal pressure, thereby improving the safety of the battery assembly (100). By having the frame (150) cover the upper surface of the battery cell stack (120), strong durability against deformation caused by the expansion of the battery cell (110) can be provided, and stable gas discharge can be guaranteed. Additionally, the venting hole (151) forms an optimal path for gas discharge, thereby increasing the overall thermal stability and durability of the battery assembly (100).

[0090] Referring again to FIGS. 4 to 6, the second resin layer (140) can be applied while avoiding the portion corresponding to the venting hole (151).

[0091] As described above, due to the presence of the first resin layer (130), the venting gas can be induced to be discharged to the second surface (120b) rather than the first surface (120a) of the battery cell stack (120). Additionally, the second resin layer (140) applied to the second surface (120b) is applied while avoiding the portion corresponding to the venting hole (151), so that the second resin layer (140) does not obstruct the discharge of the venting gas. The second resin layer (140) can help implement a directional venting structure that induces the discharge of the venting gas in the direction where the venting hole (151) of the frame (150) is provided.

[0092] By applying the second resin layer (140) so as to avoid the portion corresponding to the venting hole (151), gas generated inside the battery cell (110) during thermal runaway can be rapidly discharged to the outside through the venting hole (151). This prevents the venting gas discharge path from being blocked by the second resin layer (140), ensuring that gas discharge is not obstructed and that the increase in internal pressure of the battery cell stack (120) is minimized, thereby guaranteeing the safety of the battery assembly (100). Additionally, since the second resin layer (140) is not applied around the venting hole (151), a path for the gas to flow freely is secured, thereby improving the gas discharge performance during thermal runaway.

[0093] The second resin layer (140) may mainly comprise a silicone-based resin with high heat resistance or a heat-resistant polymer material, and the second resin layer (140) may be positioned to avoid a certain portion centered on the venting hole (151) to prevent mutual interference between the cooling path and the venting gas discharge path. The second resin layer (140) may be applied thinly and uniformly over the entire upper surface excluding the area around the venting hole (151), thereby functioning to block the refrigerant from penetrating other areas of the battery cell stack (120).

[0094] The area where the second resin layer (140) is not applied so as not to overlap with the venting hole (151) can form a path through which the venting gas can be smoothly discharged to the outside. The method of applying the second resin layer (140) can use precise masking technology to accurately apply the resin only to the area excluding the area around the venting hole (151), and can be quickly fixed through UV curing or heat curing methods as needed.

[0095] By physically separating the refrigerant path and the venting gas path, cooling effect and safety can be achieved simultaneously. The second resin layer (140), which is applied while avoiding the part corresponding to the venting hole (151), can secure the venting gas path while preventing the refrigerant from entering the venting gas path and obstructing the venting gas discharge. The method of applying the second resin layer (140) can increase the long-term thermal stability of the battery assembly (100) by blocking the refrigerant from spreading to the upper part of the battery cell stack (120) while maintaining the gas discharge path.

[0096] Referring again to FIGS. 4 to 6, at least a portion of the second resin layer (140) may be applied along the edge of the second surface (120b) of the battery cell laminate (120).

[0097] The portion applied to the edge of the second resin layer (140) can serve to reinforce the sealing structure separating the inside and outside of the battery cell stack (120) and to block the refrigerant from flowing into the second surface (120b) of the battery cell stack (120). The second resin layer (140) can be made of a silicone-based resin or a similar material with excellent high temperature and chemical stability, and the application thickness can be uniformly maintained at 0.5 mm or more and 1 mm or less.

[0098] The second resin layer (140) according to the present embodiment is precisely applied along the edge of the second surface (120b) of the battery cell stack (120), and the area around the venting hole (151) may be designed to avoid application. This allows the refrigerant and the venting gas to maintain their respective paths and act independently without mutual interference. As a method of applying the second resin layer (140), a precise spray coating or a patterned application method using a dispenser device may be used. This method allows the second resin layer (140) to uniformly fill the space between the second surface (120b) of the battery cell stack (120) and the frame (150), while ensuring that the venting gas discharge path is not blocked.

[0099] Additionally, the second resin layer (140) can be designed to remain stable without deformation even during repeated thermal and cooling cycles, and to function properly without cracking even under external impact or battery cell (110) expansion conditions. This prevents refrigerant leakage at the edges of the battery cell stack (120) and maximizes the efficiency of the cooling system.

[0100] By applying a second resin layer (140) to the edge of the second surface (120b) of the battery cell stack (120), it is possible to prevent the refrigerant from flowing into the edge and encroaching upon the internal structure and the venting gas discharge path. Additionally, by blocking mutual interference between the refrigerant path and the gas discharge path, the venting gas can be rapidly discharged even in situations such as thermal runaway. In other words, this structure prevents the refrigerant from flowing into the battery cell stack (120), thereby maintaining the chemical stability of the battery assembly (100) and enhancing the safety of the battery system.

[0101] The edge application method of the second resin layer (140) can also contribute to increasing cooling efficiency. The second resin layer (140) can restrict the diffusion of the refrigerant into a specific area, thereby optimizing the cooling path. This improves the overall thermal management performance of the battery cell stack (120) and ensures the long-term reliability of the battery assembly (100).

[0102] Referring again to FIGS. 1 to 6, by means of the second resin layer (140), the refrigerant may not flow into the area between the part of the frame (150) where the venting hole (151) is located and the second surface (120b) of the battery cell stack (120).

[0103] The second resin layer (140) according to the present embodiment can serve to block the refrigerant from flowing into the second surface (120b) of the battery cell stack (120). To this end, the second resin layer (140) can be uniformly applied to the space between the second surface (120b) of the battery cell stack (120) and the frame (150), thereby preventing the refrigerant from flowing into the gas discharge path through the venting hole (151). The second resin layer (140) may include a silicone-based high-temperature resistant resin with excellent thermal resistance and chemical resistance that can maintain its physical shape even under high temperature and high pressure conditions, and can be applied with a thickness of 0.5 mm or more and 1 mm or less to maximize the refrigerant blocking performance.

[0104] The second resin layer (140) can be uniformly distributed along the edge of the second surface (120b) of the battery cell stack (120) to prevent the refrigerant from leaking into other areas. This allows a certain distance to be maintained from the periphery of the venting hole (151) so that there is no physical interference with the venting gas discharge path. That is, when the cooling system is in operation, the second resin layer (140) can be designed to block the refrigerant from flowing in through the venting hole (151), thereby preventing any obstruction during venting gas discharge.

[0105] By blocking the refrigerant from flowing between the portion where the venting hole (151) of the frame (150) is located and the second surface (120b) of the battery cell laminate (120) by the second resin layer (140), the venting gas discharge path can be maintained stably. That is, it is possible to prevent a situation where the refrigerant intrudes into the venting gas discharge path and obstructs gas discharge, or where the discharge efficiency decreases due to the mixing of gas and refrigerant. Therefore, even in high-temperature situations such as thermal runaway, the venting gas is quickly discharged to the outside, thereby minimizing the pressure rise inside the battery assembly (100) and reducing the risk of explosion.

[0106] In addition, the second resin layer (140) prevents leakage of the refrigerant, thereby blocking the refrigerant from diffusing to other parts of the battery cell stack (120), so that the cooling performance of the battery system can be maintained more effectively. Through this, the battery assembly (100) can have more stable thermal management, and long-term reliability and safety can be improved.

[0107] FIG. 8 is a perspective view showing a battery cell (110) according to one embodiment of the present invention. FIG. 9 is a partial perspective view showing a part of the battery cell (110) of FIG. 8. FIG. 10 is a cross-sectional view showing a cross section cut along the cutting line A-A' of FIG. 3.

[0108] Referring to FIGS. 8 to 10, the battery cell (110) includes a sealing portion (111), and at least a portion of the sealing portion may be positioned to face a second surface (120b) of the battery cell stack (120).

[0109] The sealing portion (111) according to the present embodiment can block the electrolyte inside the battery cell (110) from leaking out and protect the battery cell (110) from the external environment. In particular, at least a portion of the sealing portion (111) is positioned to face the second surface (120b) of the battery cell stack (120), thereby allowing the gas to be guided in a direction desired by the user when the internal pressure of the battery cell (110) increases even in a thermal runaway situation.

[0110] The sealing portion (111) can be made of a material capable of withstanding high temperature and pressure, for example, a high heat-resistant polymer material or a metal-coated polymer, and can be formed in a multilayer structure to increase durability.

[0111] The sealing portion (111) can be released by the venting gas generated when thermal runaway occurs in the battery cell (110). That is, the venting gas generated from the battery cell (110) is likely to be discharged in the direction where the sealing portion (111) is located. As previously described, the battery assembly (100) may have a directional venting structure that induces the discharge of venting gas in the direction where the venting hole (151) of the frame (150) is provided. The directional venting structure can be more clearly implemented by positioning at least a portion of the sealing portion (111) to face the second surface (120b) of the battery cell stack (120).

[0112] The arrangement of the sealing portion (111) can be optimized to align with the second surface (120b) of the battery cell stack (120) so that gas can be smoothly discharged in a direction toward the second surface (120b). In this way, the arrangement of the sealing portion (111) toward the second surface (120b) of the battery cell stack (120) is linked with the venting hole (151) of the frame (150) and can contribute to ensuring smooth gas discharge.

[0113] By positioning the sealing portion (111) of the battery cell (110) so as to face the upper surface of the battery cell stack (120), i.e., the second surface (120b), high-temperature gas generated inside the battery assembly (100) during a thermal runaway situation can be guided upward and safely discharged to the outside. This arrangement can help the gas to be quickly discharged through the upper venting hole (151) and can rapidly relieve the rise in internal pressure, thereby reducing the risk of explosion of the battery assembly (100).

[0114] Additionally, a configuration in which the sealing portion (111) is positioned to face the second surface (120b) of the battery cell stack (120) can prevent leakage of the internal material of the battery cell (110) even under thermal expansion or impact, thereby ensuring the long-term reliability of the battery assembly (100). By maintaining sealing performance even when the battery cell stack (120) expands, the sealing portion (111) can maintain the chemical stability of the battery assembly (100) and block electrolyte leakage. This allows the battery cell (110) to operate stably even in high temperature and high pressure environments, and improves the overall safety and durability of the battery assembly (100).

[0115] Referring again to FIG. 3 and FIG. 10, the battery assembly (100) may further include a pad (190) that is positioned between battery cell stacks (120) and has cooling holes (191) through which a refrigerant flows.

[0116] The pad (190) according to the present embodiment is inserted between the battery cell stacks (120) and can effectively remove heat generated from the battery cell (110) through a refrigerant. The cooling hole (191) is formed in a structure that penetrates the interior of the pad (190), and heat exchange with the battery cell (110) can occur as the refrigerant flows through the cooling hole (191).

[0117] The pad (190) may be made of a high thermal conductivity material, for example, an aluminum alloy, a copper-based metal material, or a polymer material with excellent thermal conductivity. Additionally, the surface may include a waterproof coating or an insulating layer to prevent chemical reactions with the refrigerant. The cooling holes (191) may be formed continuously along the length of the pad (190) or arranged in a grid shape to maximize the contact area with the battery cell (110).

[0118] The refrigerant passes through the cooling holes (191) inside the pad (190) and can rapidly absorb and remove heat generated from the battery cell (110). The diameter and spacing of the cooling holes (191) can be optimized according to the flow rate of the refrigerant and the amount of heat generated by the battery cell (110), for example, the diameter can be designed to be 1 mm or more and 5 mm or less. As the refrigerant passes through the pad (190), it can uniformly remove heat from the battery cell stack (120) to maintain a constant temperature distribution. Additionally, the pad (190) can maintain the spacing between the battery cell stacks (120) to also serve as a structural buffer against expansion or pressure of the battery cell (110).

[0119] The thermal management performance of the battery assembly (100) can be significantly improved by placing a pad (190) between the battery cell stacks (120) and forming a cooling hole (191) through which a refrigerant flows. By circulating the refrigerant through the cooling hole (191) and rapidly absorbing the heat generated in the battery cell (110), the battery cell (110) can be prevented from overheating. This prevents performance degradation and shortening of the lifespan of the battery assembly (100), and can suppress dangerous situations such as thermal runaway in advance.

[0120] The introduction of a pad (190) having cooling holes (191) can increase the efficiency and stability of the battery assembly (100) by maintaining a uniform temperature distribution within the battery cell stack (120). This allows for efficient thermal management of individual battery cells (110), thereby minimizing performance degradation and damage to the battery assembly (100) caused by high temperatures. Additionally, the pad (190) can improve the durability and shock resistance of the battery assembly (100) by maintaining the spacing between the battery cells (110) and providing structural stability.

[0121] Meanwhile, in one embodiment of the present invention, at least a portion of the second resin layer (140) may be applied to an area corresponding to the pad (190).

[0122] The second resin layer (140) according to the present embodiment is applied to the second surface (120b) of the battery cell stack (120), and a portion thereof may be applied to an area corresponding to the pad (190) located between the battery cell stacks (120). By applying the second resin layer (140) to the area corresponding to the pad (190), it is possible to prevent the refrigerant flowing through the cooling hole (191) inside the pad (190) from diffusing to the outside of the pad (190). That is, the situation in which a portion of the refrigerant is absorbed by the pad (190), then penetrates into the second surface (120b) of the battery cell stack (120) and enters the gas discharge path can be effectively blocked. Since the refrigerant does not leak to the outside of the pad (190), the cooling path is maintained efficiently, and the thermal management performance of the battery assembly (100) can be optimized.

[0123] Additionally, by applying the second resin layer (140) to the area corresponding to the pad (190), the refrigerant and venting gas paths can be clearly separated. Through this, the safety of the battery system can be significantly improved by simultaneously improving cooling performance and gas exhaust performance. That is, since it supports the efficient operation of the cooling hole (191) while preventing refrigerant leakage, the internal heat distribution of the battery assembly (100) can be maintained uniformly.

[0124] The material of the second resin layer (140) may be a silicone-based material with excellent heat resistance and chemical resistance, and the coating thickness may be uniformly maintained at 0.5 mm or more and 1 mm or less. In addition, the second resin layer (140) may be applied only to the contact area between the pad (190) and the battery cell laminate (120) using a precision coating device, and may be fixed by a heat curing or UV curing method to form a stable physical structure.

[0125] FIG. 11 is an exploded perspective view showing the connection relationship between the housing (160) and the end cover (200) of FIG. 1. FIG. 12 is an exploded perspective view showing a housing according to another embodiment of the present invention. FIG. 13 is a perspective view showing an end cover (200) according to an embodiment of the present invention. FIG. 14 is a cross-sectional view showing a cross-section cut along the cutting line B-B' of FIG. 3.

[0126] Referring to FIGS. 1 to 3 and FIGS. 11 to 14, the housing (160) includes a second opening (162) and a third opening (163) that are open in directions facing each other, and end covers (200) may be positioned at each of the second opening (162) and the third opening (163).

[0127] In particular, when comparing FIG. 11 and FIG. 12, in FIG. 11 the upper part of the housing (160) is not covered, so the first opening (161) may refer to the entire open upper part of the housing (160). That is, the first opening (161) may include the entire upper part of the housing (160).

[0128] On the other hand, as illustrated in FIG. 12, the housing (160) may include an upper cover (160a). In this case, a first opening (161) may be provided in the upper cover (160a). The upper cover (160a) may be designed to cover the open upper portion of the housing (160) to protect internal components from the external environment, while allowing venting gas to be discharged to the outside through the first opening (161). This configuration can enhance the airtightness of the housing (160) and establish a path for gas discharge to the outside.

[0129] The above two housing (160) configurations can be selectively implemented depending on the application environment and requirements of the battery assembly (100), and each design can contribute to optimizing the stability and thermal management performance of the battery assembly.

[0130] End covers (200) located at the second opening (162) and the third opening (163) may be designed to protect components inside the housing (160) and provide sealing. The end covers (200) may be made of a highly durable metal (e.g., aluminum alloy) or a polymer material resistant to heat and chemical changes. Additionally, the end covers (200) may be in close contact with the outer surface of the housing (160) to prevent refrigerant or gas from leaking out. The end covers (200) may be designed to fit precisely to the edges of the openings of the housing (160) and may be secured by mechanical fastening means such as bolts, screws, or clamps.

[0131] By sealing the second opening (162) and the third opening (163) of the housing (160) by end covers (200), the structural stability and sealing of the battery assembly (100) can be improved. This configuration can prevent the refrigerant from leaking out or dust, moisture, etc. from the external environment from entering the housing (160), thereby increasing the reliability and lifespan of the battery assembly (100).

[0132] Additionally, by installing end covers (200) at the openings at both ends of the housing (160), assembly and maintenance of the battery assembly (100) can be facilitated. The end covers (200) can also be utilized as interfaces forming the inlet / outlet of cooling fluid and the gas discharge path, thereby increasing the thermal management efficiency of the entire system.

[0133] In one embodiment of the present invention, the previously described inlet (170) and outlet (180) may be provided in end covers (200). For example, as illustrated, the inlet (170) may be provided in one end cover (200) and the outlet (180) may be provided in another end cover (200). Additionally, although not specifically illustrated, as another example, both the inlet and the outlet may be provided in one end cover (200). Also, although not specifically illustrated, as another example, it is possible for at least one of the inlet or the outlet to be provided in a housing (160) rather than an end cover. That is, in the present invention, as long as the refrigerant can be circulated inside the housing (160), the inlet (170) and the outlet (180) may be provided in the battery assembly (100) without any specific location restrictions.

[0134] Referring again to FIGS. 11 to 14, the end cover (200) may include a main body portion (201) covering a second opening (162) or a third opening (163); and an extension portion (202) extending from the main body portion (201) to cover the outer surface of the housing (160).

[0135] The main body (201) according to the present embodiment is precisely designed to fit the edge of the opening of the housing (160) and can completely cover the opening (162, 163) of the housing (160). The main body (201) may be made of aluminum alloy, high-strength stainless steel, or a polymer material with excellent chemical resistance and heat resistance for durability and sealing. The main body (201) may be used with mechanical fastening means such as bolts or screws to be firmly fixed to the opening (162, 163) of the housing (160), or with a high-strength adhesive (230).

[0136] The extension part (202) extends outward from the main body part (201) and can cover a certain portion of the outer surface of the housing (160). The extension part (202) can serve to mitigate environmental effects such as shock, vibration, dust, and water from outside the housing (160).

[0137] By including the main body (201) and the extension (202) of the end cover (200), the opening (162, 163) of the housing (160) can be completely sealed while the protection function from the external environment can be enhanced. The main body (201) effectively covers the opening (162, 163) of the housing (160), thereby preventing the leakage of refrigerant and venting gas generated inside the battery assembly (100). Through this, the cooling path and the venting gas discharge path can be stably maintained, thereby increasing the thermal management performance and safety of the battery system.

[0138] The extension (202) can reinforce the sealing performance of the housing (160) and block physical and chemical effects from the external environment by additionally covering the outer surface of the housing (160). In addition, a structure in which the extension (202) overlaps with the outer surface of the housing (160) can significantly improve the durability and stability of the battery assembly (100).

[0139] Referring again to FIGS. 11 to 14, a sealant (210) can be applied between the extension part (202) and the outer surface of the housing (160).

[0140] The sealant (210) according to the present embodiment may be selected from a material having excellent chemical stability and heat resistance, for example, a silicone-based, polyurethane-based, or epoxy-based sealant (210) may be used. Such a material does not deform even in high temperature and high pressure environments and can maintain sealing performance even under repeated thermal cycles. The sealant (210) completely fills the space between the extension (202) and the outer surface of the housing (160) through a curing process after application, and can enhance the sealing performance of the entire structure of the housing (160).

[0141] The sealant (210) can be applied uniformly to a constant thickness using precision equipment, and the curing time after application can be adjusted according to the characteristics of the material used. The joint between the extension (202) and the housing (160) to which the sealant (210) is applied may be used with mechanical fastening means (e.g., bolts or clamps). Through a double sealing structure, stable sealing can be achieved even against external impact, vibration, or thermal expansion.

[0142] By applying a sealant (210) between the extension (202) and the outer surface of the housing (160), the internal components of the housing (160) and the external environment are blocked, thereby significantly improving the sealability of the battery assembly (100). In addition, the sealant (210) prevents leakage of refrigerant and venting gas, and blocks external moisture, dust, and chemicals from entering the housing (160), thereby improving the reliability and durability of the battery assembly (100).

[0143] Additionally, the sealant (210) can reinforce structural stability by supplementing the mechanical connection between the housing (160) and the extension (202). That is, by ensuring that the housing (160) remains sealed even when exposed to external shocks, vibrations, thermal expansion, etc., the safety and durability of the battery assembly (100) can be secured in the long term.

[0144] FIG. 15 is an exploded perspective view showing a housing cover (220) according to one embodiment of the present invention. FIG. 16 is a perspective view showing a battery assembly (100) according to another embodiment of the present invention. FIG. 17 is a plan view showing the battery assembly (100) of FIG. 16.

[0145] Referring to FIGS. 15 to 17, the battery assembly (100) may further include a housing cover (220) that covers at least a portion of the frame (150) where the venting hole (151) is located.

[0146] The housing cover (220) according to the present embodiment can effectively protect internal components of the battery assembly (100) from the external environment. The housing cover (220) can prevent damage caused by external impact, vibration, or the ingress of foreign substances, and can improve the durability of the battery system. In particular, the housing cover (220) can reinforce physical strength to strengthen the mechanical stability of the housing (160) itself and prevent performance degradation of the battery assembly (100) due to external environmental factors. A part of the housing cover (220) can be combined with the housing (160).

[0147] Additionally, the housing cover (220) can provide a path through which venting gas can be rapidly discharged to the outside. This can help mitigate the rise in internal pressure in high-temperature situations, such as thermal runaway, and contribute to reducing the risk of explosion of the battery assembly (100). At the same time, the refrigerant circulation path and the gas discharge path can be maintained independently without interference, thereby increasing thermal management efficiency and maximizing the stability and performance of the battery.

[0148] The housing cover (220) may be made of a metal material with excellent durability and heat resistance (e.g., aluminum alloy, stainless steel) or a polymer material with chemical resistance and insulation properties (e.g., polycarbonate, epoxy-based material). The housing cover (220) is machined to precise dimensions to ensure a tight seal with the outer surface of the housing (160) and may be manufactured to wrap around the outer surface of the housing (160). The housing cover (220) is attached to the outer surface of the frame (150) using fixing bolts, clamps, or high-strength adhesive, and if necessary, a sealant may be additionally applied between the housing cover (220) and the housing (160) to enhance sealing performance.

[0149] Referring again to FIGS. 15 to 17, the housing cover (220) may include a venting slot (221) through which venting gas is discharged.

[0150] By including a venting slot (221) in the housing cover (220) according to the present embodiment, venting gas generated inside the battery assembly (100) can be safely and efficiently discharged to the outside. This can rapidly relieve the internal pressure of the housing (160) in high-temperature situations, such as thermal runaway, thereby reducing the risk of explosion and ensuring the safety of the battery system. In particular, by designing the venting slot (221) to be aligned with the venting hole (151) of the frame (150), the consistency and efficiency of the gas discharge path can be maximized.

[0151] Additionally, the venting slot (221) allows the gas to travel along a clear path as it is discharged to the outside through the housing cover (220), thereby minimizing gas diffusion into the external environment and reducing the impact on surrounding devices. This can contribute to protecting the vehicle or other components of the energy storage system in which the battery assembly (100) is installed.

[0152] The size and shape of the venting slot (221) can be designed considering the pressure and amount of venting gas that may occur in the battery assembly (100). For example, the venting slot (221) can be manufactured in a long elliptical or rectangular shape to allow for fast and efficient gas discharge. The size of the venting slot (221) can be formed with a width of about 5mm to 20mm and a length of 10mm to 50mm, and can be arranged in a multi-slot structure as needed to increase the discharge capacity.

[0153] A reinforced sealing structure is applied around the venting slot (221) to prevent refrigerant from leaking through a path other than the gas discharge or external contaminants from entering the housing (160). The housing cover (220) is in close contact with the outer surface of the housing (160) and can be secured using a sealant or a high-strength adhesive. This ensures that the venting gas discharge path is clearly maintained and guarantees the stability of the system.

[0154] Referring again to FIGS. 15 to 17, the venting slot (221) may overlap at least partially with the venting hole (151) of the frame (150).

[0155] According to the present embodiment, the venting slot (221) of the housing cover (220) is designed to overlap with the venting hole (151) of the frame (150), thereby allowing the venting gas to be efficiently and safely discharged to the outside. This overlapping structure maintains a clear gas discharge path, thereby rapidly mitigating the rise in internal pressure of the housing (160) even in high-temperature situations such as thermal runaway. This reduces the risk of explosion of the battery system and ensures the safety of the battery assembly (100).

[0156] In addition, the overlap of the venting slot (221) and the venting hole (151) maximizes the consistency and efficiency of the gas discharge path, allowing the gas flow to be rapidly discharged to the outside without obstruction during the discharge process. This enables effective control of the internal gas discharge time and pressure, and increases the long-term reliability of the battery assembly (100).

[0157] The overlapping structure prevents refrigerant leakage or contamination from entering the outside around the venting slot (221), thereby enabling the simultaneous realization of cooling performance of the battery system and protection of internal components.

[0158] FIG. 18 is a plan view showing a battery assembly provided with an adhesive (230) according to one embodiment of the present invention.

[0159] Referring to FIGS. 15 to 18, an adhesive (230) can be applied between the frame (150) and the housing cover (220).

[0160] The adhesive (230) according to the present embodiment can be used to firmly secure the housing cover (220) to the outer surface of the frame (150) and to ensure airtightness between the two components. The adhesive (230) applied can be selected from a material having heat resistance and chemical resistance that can maintain stability even in the high temperature and high pressure environment in which the battery assembly (100) operates. For example, silicone-based adhesives, epoxy-based adhesives, or polyurethane adhesives may be used. These materials maintain their physical properties even in an environment where thermal expansion and contraction are repeated and can provide long-term sealing performance.

[0161] Additionally, by applying the adhesive (230) between the housing cover (220) and the frame (150), movement of the housing cover (220) due to vibration or impact can be suppressed, thereby reinforcing the structural stability of the entire battery assembly (100). The adhesive (230) can also be used in conjunction with mechanical fastening means such as bolts or clamps to ensure double sealing.

[0162] By applying an adhesive (230) between the frame (150) and the housing cover (220), the airtightness and bonding strength between the two components can be significantly improved. This prevents refrigerant or venting gas from leaking out and blocks dust, moisture, contaminants, etc. from the external environment from entering the housing (160). As a result, the components inside the battery assembly (100) are protected from the external environment, thereby maintaining long-term stability and durability.

[0163] Additionally, the sealed structure using the adhesive (230) can optimize thermal management performance by maintaining the independence of the cooling path and the gas exhaust path. This prevents the refrigerant from leaking out while circulating inside the housing (160), and allows the venting gas to be efficiently discharged outward along a designated path. In particular, the adhesive (230) maintains its function even in high-temperature environments or thermal runaway situations, thereby increasing the safety of the battery system.

[0164] Consequently, the adhesive (230) can completely fill the micro-gap between the frame (150) and the housing cover (220), thereby preventing the leakage of refrigerant or venting gas. The adhesive (230) can be applied in a uniform thickness using precision equipment, and if necessary, it can be fixed by UV curing or heat curing to increase adhesive strength. This application method ensures that the adhesive (230) is not over-applied or insufficient in specific areas, thereby maximizing the performance of the adhesive (230). The adhesive (230) can be applied evenly to the entire contact surface where the frame (150) and the housing cover (220) are joined, thereby preventing the ingress of contaminants from the outside and blocking the leakage of internal refrigerant or venting gas.

[0165] FIG. 19 is a plan view showing a battery assembly having a third resin layer (240) provided according to one embodiment of the present invention.

[0166] Referring to FIGS. 15 to 17 and FIG. 19, a battery assembly (100) according to one embodiment of the present invention may further include a third resin layer (240) applied between a frame (150) and a housing cover (220).

[0167] The third resin layer (240) according to the present embodiment completely fills the gap between the frame (150) and the housing cover (220) to provide airtightness, and prevents the refrigerant from penetrating into the gap between the frame (150) and the housing (160), while also blocking external dust, moisture, and contaminants from penetrating into the interior.

[0168] The third resin layer (240) can also serve to assist in the structural bonding of the housing (160) and the housing cover (220). In particular, when the housing (160) and the housing cover (220) are mechanically fixed, the third resin layer (240) can relieve loads distributed along the contact area and improve resistance to shock or vibration. Additionally, the third resin layer (240), designed to maintain the cooling path and venting gas path inside the housing (160), can control the flow of refrigerant and gas by effectively sealing all gaps except for the venting hole (151) and the refrigerant inlet / outlet.

[0169] In particular, the third resin layer (240) has the characteristic of being able to withstand heat and pressure generated inside the housing (160) and can maintain stability without cracking even with repeated thermal expansion and contraction. This ensures the long-term reliability of the battery assembly (100) and can prevent refrigerant leakage or performance degradation due to external environmental factors. In addition, the third resin layer (240) can significantly improve the sealing properties of the battery assembly (100). The third resin layer (240) prevents external leakage of refrigerant and venting gas and effectively blocks external dust, moisture, and contaminants from entering the housing (160). As a result, the components inside the battery assembly (100) can operate stably, and the performance and lifespan of the battery system can be extended.

[0170] The third resin layer (240) may be composed of a material having excellent heat resistance and chemical resistance, and a silicone-based resin, epoxy resin, or polyurethane-based resin may be suitable. This resin is uniformly applied to the surface where the frame (150) and the housing cover (220) come into contact, and can be firmly fixed through a heat curing or UV curing method. The thickness of the third resin layer (240) may be set to be 0.1 mm or more and 1 mm or less. The third resin layer (240) may provide sufficient sealing power to completely fill the space between the housing (160) and the cover.

[0171] Referring to FIGS. 15 to 17 and FIG. 19, the third resin layer (240) can be applied while avoiding the portion corresponding to the venting hole (151).

[0172] A third resin layer (240) applied to an area not corresponding to the venting hole (151) can strengthen the bonding strength between the frame (150) and the housing cover (220) and prevent gaps that may occur due to external impact or vibration. The third resin layer (240), designed so that the venting gas discharge path is not obstructed, can block refrigerant from flowing into the gap between the frame (150) and the housing (160) or external contaminants from penetrating into the housing (160).

[0173] By applying the third resin layer (240) while avoiding the portion corresponding to the venting hole (151), the venting gas can be smoothly discharged to the outside through the venting hole (151) of the housing (160). This allows for the rapid alleviation of the increase in internal battery pressure even in high-temperature situations such as thermal runaway, and minimizes the risk of explosion. Since the venting gas discharge path and the cooling path are clearly separated, it is possible to prevent situations where the refrigerant interferes or the flow is blocked during venting gas discharge.

[0174] FIG. 20 is a partially exploded perspective view showing a part of FIG. 15.

[0175] Referring to FIGS. 15 to 17 and FIG. 20, the housing cover (220) may include a housing cover flange (222).

[0176] The housing cover flange (222) according to the present embodiment may be a structural element that extends from the outer edge of the housing cover (220) and is coupled to the flange of the housing (160). The housing cover flange (222) may contribute to firmly connecting the housing (160) and the housing cover (220) and enhancing the sealing of the battery assembly (100).

[0177] The housing cover flange (222) may be made of a highly durable material such as aluminum alloy, stainless steel, or high-strength plastic to ensure strength and durability. The width and thickness of the housing cover flange (222) may be designed according to the mechanical requirements of the housing (160) and the housing cover (220) and the size of the battery assembly (100), and a corrosion-resistant coating may be applied to the surface of the housing cover flange (222) to maintain stable performance even with long-term use.

[0178] Additionally, the housing cover flange (222) can also perform the function of mitigating external shocks or vibrations. The connection between the flange and the housing (160) ensures the structural stability of the battery assembly (100) and can strengthen the durability of the battery assembly (100) by maintaining the connection strength even with thermal expansion and contraction.

[0179] Referring again to FIGS. 15 to 17 and FIG. 20, the housing (160) may include a housing flange (223) that is coupled to a housing cover flange (222).

[0180] The housing flange (223) according to the present embodiment is a protruding structure formed on the outer surface of the housing (160) and can serve to firmly connect the two components by combining with the housing cover flange (222). The housing flange (223) can ensure the airtightness and structural stability of the battery assembly (100) while effectively maintaining the path of the refrigerant and venting gas.

[0181] The housing flange (223) is designed to interlock with the housing cover flange (222) and may be made of a material having a suitable thickness and strength so that it can be stably maintained against external shocks or vibrations when joined. For example, the housing flange (223) may be made of aluminum alloy, stainless steel, or a high-strength polymer material. The surface of the housing flange (223) may be coated to enhance corrosion resistance and durability, or surface processed to reduce friction with the housing cover flange (222).

[0182] The housing flange (223) and the housing cover flange (222) can be mechanically joined using bolts, screws, or clamps, and a sealant or gasket may be additionally applied to the joint. This sealed structure prevents refrigerant or venting gas from leaking out of the housing (160) and can block external dust, moisture, and contaminants from entering the housing (160).

[0183] By including a housing flange (223) that is coupled to the housing cover flange (222) in the housing (160), the coupling strength and sealing between the housing (160) and the housing cover (220) can be significantly improved. The housing flange (223) ensures airtightness between the two components through precise coupling with the housing cover flange (222) and can completely block the path of the refrigerant and venting gas from the external environment. As a result, the internal components of the battery assembly (100) can be reliably protected.

[0184] The housing cover flange (222) and the housing flange (223) can be bolted together.

[0185] The bolt connection method according to the present embodiment can contribute to strengthening the airtightness and structural stability of the battery assembly (100) by firmly connecting the housing cover (220) and the housing (160). The housing flange (223) and the housing cover flange (222) are designed to interlock with each other and are joined through a bolt passing through them to provide stable fastening force.

[0186] The bolt connection is made through threaded holes and bolt holes formed at appropriate locations on the housing cover flange (222) and the housing flange (223). The bolts used may be made of a material that is durable against external impact, vibration, thermal expansion and contraction, and, for example, stainless steel or high-strength alloy bolts may be used. Additionally, a gasket or sealing washer may be additionally inserted around the bolt holes to ensure sealing after bolt fastening.

[0187] Sealant or adhesive (230) may be applied to the joint between the housing flange (223) and the housing cover flange (222) to enhance airtightness. This prevents leakage of refrigerant and venting gas and blocks the ingress of dust or moisture from the outside. The bolt connection method allows for easy assembly and disassembly, which simplifies maintenance work on the battery assembly (100) and allows the housing cover (220) to be easily replaced or repaired if necessary.

[0188] By connecting the housing cover flange (222) and the housing flange (223) through a bolt connection, the structural strength and airtightness of the battery assembly (100) can be improved. Additionally, the bolt connection facilitates easy assembly and disassembly, allowing for efficient maintenance and replacement of the battery assembly (100). This can contribute to minimizing downtime of the battery assembly (100) and reducing maintenance costs for the entire system.

[0189] By additionally applying sealants, gaskets, or sealing washers to the joints, leakage of refrigerants and venting gases can be prevented, and the reliability and performance of the battery system can be maintained by blocking external contaminants from entering the interior. In particular, the safety of the system can be guaranteed by ensuring that the gas discharge path remains stable even in extreme situations such as thermal runaway.

[0190] According to another embodiment of the present invention, a battery pack including a battery assembly (100) may be provided.

[0191] One or more battery assemblies (100) according to the embodiment described above can be mounted together with various control and protection systems, such as a Battery Management System (BMS), a Battery Disconnect Unit (BDU), and a cooling system, to form a battery pack.

[0192] The battery assembly (100) or battery pack can be applied to various devices. Specifically, it can be applied to means of transportation such as electric bicycles, electric vehicles, and hybrids, but is not limited thereto and can be applied to various devices capable of using secondary batteries.

[0193] In this embodiment, terms indicating directions such as front, back, left, right, up, and down have been used; however, these terms are for convenience of explanation only and may vary depending on the location of the object or the observer.

[0194] Although preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements by those skilled in the art using the basic concept of the present invention as defined in the following claims also fall within the scope of the present invention.

[0195] Explanation of the symbols

[0196] 100: Battery assembly

[0197] 110: Battery cell

[0198] 120: Battery cell stack

[0199] 130: 1st resin layer

[0200] 140: Second resin layer

[0201] 150: Frame

[0202] 151: Benting Hall

[0203] 160: Housing

[0204] 170: Inlet

[0205] 180: Outlet

[0206] 190: Pad

[0207] 200: End cover

[0208] 220: Housing cover

[0209] 230: Adhesive

[0210] 240: Third resin layer

Claims

1. A battery cell stack comprising multiple stacked battery cells; A first resin layer applied to a first surface of the battery cell laminate; A second resin layer applied to a second surface located opposite the first surface of the battery cell laminate; A frame covering at least a portion of the battery cell stack and including a venting hole through which venting gas is discharged; and A battery assembly comprising an inlet and an outlet for circulating a refrigerant into the frame.

2. In Paragraph 1, A battery assembly in which the portion of the above frame where the venting hole is located covers the second surface of the battery cell stack.

3. In Paragraph 1, A battery assembly in which the second resin layer is applied while avoiding the portion corresponding to the venting hole.

4. In Paragraph 1, A battery assembly in which at least a portion of the second resin layer is applied along the edge of the second surface of the battery cell laminate.

5. In Paragraph 1, A battery assembly in which the refrigerant is not introduced into the region between the portion of the frame where the venting hole is located and the second surface of the battery cell laminate by means of the second resin layer.

6. In Paragraph 1, The above battery cell includes a sealing portion, and A battery assembly in which at least a portion of the sealing portion is positioned to face the second surface of the battery cell stack.

7. In Paragraph 1, A battery assembly further comprising a pad positioned between the battery cell stacks and having a cooling hole formed therein through which the refrigerant flows.

8. In Paragraph 7, A battery assembly in which at least a portion of the second resin layer is applied to an area corresponding to the pad.

9. In Paragraph 1, The above battery cell stack and the above frame are further included in a housing that accommodates them. A battery assembly having a first opening provided in the housing that overlaps at least a portion with the venting hole.

10. In Paragraph 9, The above housing includes a second opening and a third opening that are open in directions facing each other, and A battery assembly having end covers located at each of the second opening and the third opening.

11. In Paragraph 10, A battery assembly comprising: a main body portion covering the second opening or the third opening; and an extension portion extending from the main body portion and covering the outer surface of the housing.

12. In Paragraph 11, A battery assembly in which a sealant is applied between the extension and the outer surface of the housing.

13. In Paragraph 1, A battery assembly further comprising a housing cover that covers at least a portion of the part of the frame where the venting hole is located.

14. In Paragraph 13, The above housing cover is a battery assembly including a venting slot through which venting gas is discharged.

15. In Paragraph 14, A battery assembly in which the above-mentioned venting slot overlaps at least partially with the above-mentioned venting hole.

16. In Paragraph 13, A battery assembly in which an adhesive is applied between the above frame and the above housing cover.

17. In Paragraph 13, A battery assembly further comprising a third resin layer applied between the above frame and the above housing cover.

18. In Paragraph 17, A battery assembly in which the third resin layer is applied while avoiding the portion corresponding to the venting hole.

19. In Paragraph 13, The above housing cover is a battery assembly including a housing cover flange.

20. In Paragraph 19, The above battery cell stack and the above frame are further included in a housing that accommodates them. A battery assembly comprising a housing flange that is coupled to the housing cover flange.

21. In Paragraph 20, A battery assembly in which the housing cover flange and the housing flange are bolted together.

22. A battery pack comprising a battery assembly according to paragraph 1.

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