Battery assembly and battery pack including the same

Abstract

A battery assembly according to one embodiment of the present invention comprises: a plurality of battery cells; and a cell frame in which the battery cells are housed. The cell frame comprises a bottom cell frame on which the battery cells are seated and a cover cell frame located on the bottom cell frame. A refrigerant circulates inside the cell frame while in direct contact with the battery cells. Between the bottom cell frame and the cover cell frame, a spacer is formed on at least one of one surface of the bottom cell frame or one surface of the cover cell frame facing each other. The spacer protrudes along a direction perpendicular to the one surface of the bottom cell frame or the one surface of the cover cell frame.

Description

Technology Field

[0001] The present invention relates to a battery assembly and a battery pack including the same, and more specifically, to an immersion cooling type battery assembly and a battery pack including the same. Background Technology

[0002] Secondary batteries, which have high applicability across product groups and electrical characteristics such as high energy density, are widely applied not only to portable devices but also to electric vehicles (EVs) or hybrid electric vehicles (HEVs) driven by electric power sources. These secondary batteries are widely used as an energy source for enhancing eco-friendliness and energy efficiency, not only because of the primary advantage of being able to drastically reduce the use of fossil fuels, but also because they do not generate any by-products from energy use.

[0003] Types of secondary batteries include lithium-ion batteries, lithium-polymer batteries, nickel-cadmium batteries, nickel-hydrogen batteries, and nickel-zinc batteries. The operating voltage of these unit secondary battery cells, that is, unit battery cells, is approximately 2.5V to 4.5V. Therefore, if a higher output voltage is required, a battery pack may be formed by connecting multiple battery cells in series. Additionally, a battery pack may be formed by connecting multiple battery cells in parallel depending on the charge / discharge capacity required for the battery pack. Accordingly, the number of battery cells included in the battery pack can be set in various ways depending on the required output voltage or charge / discharge capacity.

[0004] Meanwhile, when configuring a battery pack by connecting multiple battery cells in series or parallel, it is common to first form a battery module by creating a battery cell assembly containing multiple battery cells and housing it in a module case, and then configuring a battery pack by assembling one or more of these battery modules and adding other components, or by arranging multiple battery cells within a pack frame and adding other components.

[0005] Since these battery cells consist of rechargeable secondary batteries, such high-output, high-capacity secondary batteries generate a significant amount of heat during the charging and discharging process. In this case, the heat emitted from multiple battery cells is aggregated within a confined space, causing the temperature to rise rapidly and severely. In other words, while battery packs containing multiple cells can achieve high output, it is not easy to dissipate the heat generated by the cells during charging and discharging. If heat dissipation from the battery cells is not properly carried out, the cells degrade rapidly, shortening their lifespan and increasing the risk of explosion or ignition.

[0006] Furthermore, automotive battery packs are frequently exposed to direct sunlight and may be subjected to high-temperature conditions, such as during the summer or in desert regions. Additionally, because multiple battery cells are densely packed to extend a vehicle's driving range, flames or heat generated in a single battery cell can easily spread to neighboring cells, ultimately leading to the ignition or explosion of the battery pack itself.

[0007] In conventional battery modules, bottom cooling or side cooling methods have been used, in which a heat sink is mounted on the module case of the battery module to cool it.

[0008] However, in the case of battery modules using this cooling method, heat generated from the battery cells is transferred to a heat sink on one side of the module case for cooling, making it difficult to establish a heat transfer path to the other side of the module case. Consequently, there are limitations, such as intensified temperature differences between one end and the other of the battery cell assembly, or unsatisfactory overall cooling efficiency. If these temperature differences are not resolved, issues regarding the safety and durability of the battery module arise. Poor cooling efficiency can accelerate the degradation of battery cells or lead to the spread of thermal runaway if a rapid response is not possible when it occurs in some cells. This can result in disasters such as ignition and explosion of the battery module or the battery pack containing it, causing not only property damage but also safety issues.

[0009] To solve this problem, it has been proposed to use a method of directly cooling the battery cells by filling the inside of the battery pack with coolant or insulating oil, rather than relying on bottom cooling or side cooling. That is, to effectively cool high-capacity battery packs, an immersion cooling method is used in which a refrigerant directly cools the battery cells inside the battery pack.

[0010] However, implementing this immersion cooling method requires a stable waterproof structure. Since the refrigerant circulates within the battery pack, conventional immersion cooling methods employ various components, such as gaskets or waterproof foam tape, to create a waterproof structure. Because this waterproof structure achieves waterproof performance by inserting separate components between parts requiring sealing and applying pressure through separate fixing members, it presents the problem of requiring various materials, including waterproof foam tape, sealants, silicone rubber parts such as O-rings, and bolting structures. The application of such diverse components increases the number of parts, making the assembly and manufacturing processes complex, and increases costs due to the need for separate fixing structures. Furthermore, there is a problem where the assembly and manufacturing processes become sensitive to foreign matter, leading to a high risk of defects. The problem to be solved

[0011] The problem that the present invention aims to solve is to provide an immersion cooling type battery assembly having a stable waterproof structure while simplifying the assembly and manufacturing processes, and a battery pack including the same.

[0012] 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. means of solving the problem

[0013] A battery assembly according to one embodiment of the present invention comprises: a plurality of battery cells; and a cell frame in which the battery cells are housed. The cell frame comprises a bottom cell frame on which the battery cells are seated and a cover cell frame located on the bottom cell frame. A refrigerant circulates inside the cell frame while in direct contact with the battery cells. Between the bottom cell frame and the cover cell frame, a spacer is formed on at least one of one surface of the bottom cell frame or one surface of the cover cell frame facing each other. The spacer protrudes along a direction perpendicular to the one surface of the bottom cell frame or the one surface of the cover cell frame.

[0014] The above spacer may be in a shape that protrudes along the height direction.

[0015] The spacer formed on one surface of the bottom cell frame can protrude toward the cover cell frame.

[0016] The spacer formed on one surface of the cover cell frame can protrude toward the bottom cell frame.

[0017] The spacer may be pressed by the force with which the bottom cell frame and the cover cell frame are assembled.

[0018] The gap between the bottom cell frame and the cover cell frame can be sealed by the spacer.

[0019] The spacer may be positioned on the outer perimeter of the area where the battery cells are seated in the cell frame.

[0020] The spacer may extend along the outer perimeter of the area where the battery cells are seated in the cell frame.

[0021] The bottom cell frame and the cover cell frame can be joined by a bolt member.

[0022] A groove may be formed on the outer perimeter of the area where the battery cells are seated in the bottom cell frame.

[0023] The above cover cell frame can be assembled into the groove of the above bottom cell frame.

[0024] A waterproof adhesive may be applied to the bottom cell frame, and at least a portion of the waterproof adhesive may be applied to the portion where the cover cell frame is assembled in the groove of the bottom cell frame.

[0025] The above cover cell frame may include a rib that is engaged with the bottom cell frame.

[0026] The cell frame may include an inlet port through which the refrigerant flows into the cell frame and an outlet port through which the refrigerant is discharged to the outside of the cell frame.

[0027] The above battery cells may be fitted inside the cell frame.

[0028] The above refrigerant may be insulating oil or cooling water.

[0029] The above battery cells can be directly mounted on a vehicle or chassis while housed in the cell frame.

[0030] A battery pack according to one embodiment of the present invention comprises: the battery assembly; a pack frame housing the battery assembly and having one side open; and a pack cover covering the open side of the pack frame. Effects of the invention

[0031] According to embodiments of the present invention, by providing a spacer that protrudes at the interface of a cell frame in which battery cells are housed, the waterproof performance in an immersion cooling method can be increased.

[0032] 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. Brief explanation of the drawing

[0033] FIG. 1 is a perspective view showing a battery assembly according to one embodiment of the present invention. Figure 2 is a plan view showing the battery assembly of Figure 1 as viewed along the -z axis direction in the xy plane. Figure 3 is an exploded perspective view of the battery assembly of Figure 1. FIG. 4 (a) and (b) are a perspective view and a side view, respectively, of a battery cell according to one embodiment of the present invention. Figure 5 is a cross-sectional view showing the cross-section cut along the cutting line C-C' in Figure 4 (a). FIG. 6 is a cross-sectional view of a battery cell according to one embodiment of the present invention. FIG. 7 is a partial perspective view of the battery assembly of FIG. 1. Figure 8 is a cross-sectional view showing a cross-section cut along the cutting line A-A' of Figure 2. Figure 9 is a partial cross-sectional view showing an enlarged view of section “D” of Figure 8. Figure 10 is a partial cross-sectional view showing an enlarged view of section “E” of Figure 8. Figure 11 is a cross-sectional view showing a cross-section cut along the cutting line B-B' of Figure 2. FIG. 12 is a partial cross-sectional view showing an enlarged view of the “F” portion of FIG. 9. FIG. 13 is a partial cross-sectional view showing an enlarged view of the “G” portion of FIG. 10. FIG. 14 is a perspective view showing a bottom cell frame and battery cells according to one embodiment of the present invention. FIG. 15 is a plan view showing a bottom cell frame according to one embodiment of the present invention as viewed along the -z axis direction in the xy plane. FIGS. 16 and FIGS. 17 are cross-sectional perspective views of a bottom cell frame according to one embodiment of the present invention. FIG. 18 is a cross-sectional view showing a cross-section cut along the cutting line H-H' of FIG. 2. FIG. 19 is a partial cross-sectional view showing an enlarged view of section “I” of FIG. 19. FIG. 20 is a perspective view of a cover cell frame according to one embodiment of the present invention. FIG. 21 is a plan view showing the cover cell frame of FIG. 20 as viewed along the +z-axis direction in the xy-plane. FIG. 22 is a cross-sectional view showing a cross section according to another embodiment of the present invention. FIG. 23 is a cross-sectional view showing a cross section according to another embodiment of the present invention. FIG. 24 is a cross-sectional perspective view of a middle cell frame according to one embodiment of the present invention. FIG. 25 is an exploded perspective view showing a third waterproof adhesive and a bottom cell frame according to one embodiment of the present invention. FIG. 26 is an exploded perspective view showing a second waterproof adhesive and a middle cell frame according to one embodiment of the present invention. FIG. 27 is an exploded perspective view showing a first waterproof adhesive and a top cell frame according to one embodiment of the present invention. FIGS. 28 and FIGS. 29 are exploded perspective views of a battery pack according to one embodiment of the present invention. Specific details for implementing the invention

[0034] 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.

[0035] 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.

[0036] 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.

[0037] 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.

[0038] 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.

[0039] 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.

[0040] FIG. 1 is a perspective view showing a battery assembly according to an embodiment of the present invention. FIG. 2 is a plan view showing the battery assembly of FIG. 1 viewed along the -z axis direction in the xy plane. FIG. 3 is an exploded perspective view of the battery assembly of FIG. 1.

[0041] Referring to FIGS. 1 to 3, a battery assembly (100) according to one embodiment of the present invention comprises a plurality of battery cells (110); and a cell frame (120) in which the battery cells (110) are housed. The cell frame (120) comprises a bottom cell frame (120c) on which the battery cells (110) are seated and a cover cell frame (120ab) located on the bottom cell frame (120c). In the battery assembly (100), a coolant circulates inside the cell frame (120) while in direct contact with the battery cells (110). That is, in the battery assembly (100) according to the present embodiment, an immersion cooling method is applied in which the coolant directly cools the battery cells. In the present invention, at least a portion of the battery cells (110) may be cooled by contacting the coolant. That is, in one embodiment, a portion of the outer surface of the battery cell (110) may be in contact with the refrigerant, and in another embodiment, the entire outer surface of the battery cell (110) may be in contact with the refrigerant.

[0042] Between the bottom cell frame (120c) and the cover cell frame (120ab), a spacer is formed on at least one of the sides of the bottom cell frame (120c) or the cover cell frame (120ab) facing each other. The structure of the spacer will be described later.

[0043] Hereinafter, the battery cell (110) according to the present embodiment will be described in detail. The battery cell (110) according to the present embodiment can be any type of secondary battery, such as a prismatic, cylindrical, or pouch-type battery cell. However, below, as an example, the battery cell (110) which is a cylindrical cell will be described.

[0044] FIG. 4(a) and FIG. 4(b) are a perspective view and a side view, respectively, of a battery cell according to an embodiment of the present invention. FIG. 5 is a cross-sectional view showing a cross section cut along the cutting line C-C' in FIG. 4(a). FIG. 6 is a cross-sectional view of a battery cell according to an embodiment of the present invention.

[0045] Referring to FIGS. 4 to 6, the battery cell (110) according to the embodiments may be a cylindrical cell and may have a vent portion (110V). The vent portion (110V) is a general term for a component or mechanism provided in the battery cell (110) to discharge venting gas, etc., inside the battery cell (110). In addition, each battery cell (110) may be provided with a first electrode terminal (111) and a second electrode terminal (112) as positive and negative electrode terminals.

[0046] For example, the battery cell (110) according to the present embodiment may be a cylindrical battery cell. Specifically, the battery cell (110) may include an electrode assembly (10); a battery can (20) that houses the electrode assembly (10) and has an open top; and a cap assembly (30) that is coupled to the open top of the battery can (20). A gasket (50) may be interposed between the battery can (20) and the cap assembly (30). An exemplary structure of the battery cell (110) is described below, but the battery cell of the present invention is not limited to such a structure.

[0047] The battery can (20) according to the present embodiment may be a cylindrical case with an open top, and may contain an electrode assembly (10) and an electrolyte (not shown) in an internal storage space, and may include a metal material such as aluminum (Al).

[0048] The cap assembly (30) according to the present embodiment may include a top cap (31) having a plate shape and a connecting plate (32) electrically and mechanically coupled to the top cap (31). The top cap (31) may include an electrically conductive metal material and may cover the open top of the battery can (20). The top cap (31) may be electrically connected to a first segment (11) connected to a first electrode of the electrode assembly (10), and at the same time may be electrically insulated from the battery can (20) by a gasket (50). Accordingly, the cap assembly (30) according to the present embodiment including the top cap (31) may function as a first electrode terminal (111), which is an external terminal of the first electrode included in the electrode assembly (10).

[0049] To specifically describe the electrical connection between the top cap (31) and the first segments (11), the battery cell (110) according to the present embodiment may further include a first current collector plate (41) located on the upper part of the electrode assembly (10). The first current collector plate (41) may include a conductive metal material such as aluminum, copper, steel, nickel, etc., and may be electrically connected to the first segments (11) of the electrode assembly (10). The electrical connection may be made through welding. A lead (60) may be connected to this first current collector plate (41). The lead (60) may extend in the upward direction of the electrode assembly (10) and be connected to the connecting plate (32). In another embodiment, the lead (60) may be directly connected to the lower surface of the top cap (31). The connection between the lead (60) and other parts may be made through welding. Additionally, the first collector plate (41) may be formed integrally with the lead (60). In this case, the lead (60) may have an elongated plate shape extending outward from near the center of the first collector plate (41).

[0050] The first collector plate (41) may have a plurality of irregularities (not shown) formed radially on its lower surface. When radial irregularities are provided, the first collector plate (41) can be pressed to press the irregularities into the bent first segments (11). The connection between the first collector plate (41) and the first segments (11) can be achieved, for example, by laser welding. Laser welding can be performed by partially melting the base material of the first collector plate (41). In a modified example, welding between the first collector plate (41) and the first segments (11) can be performed with solder interposed. In this case, the solder may have a lower melting point compared to the first collector plate (41) and the first segments (11). Laser welding can be replaced by resistance welding, ultrasonic welding, spot welding, etc.

[0051] Meanwhile, the battery cell (110) according to the present embodiment may further include a second current collector plate (42) located at the bottom of the electrode assembly (10). Specifically, the second current collector plate (42) may be located between the electrode assembly (10) and the bottom portion (20F) of the battery can (20). The second current collector plate (42) may include a conductive metal material such as aluminum, copper, steel, nickel, etc., and may be electrically connected to the second segments (12) of the electrode assembly (10). One side of the second current collector plate (42) may be connected to the second segments (12), and the opposite side of the second current collector plate (42) may be connected to the bottom portion (20F) of the battery can (20). Welding may be applied to the connection of the second current collector plate (42). Accordingly, the battery can (20) according to the present embodiment can function as a second electrode terminal (112), which is an external terminal of the second electrode included in the electrode assembly (10).

[0052] Meanwhile, the secondary battery according to the present embodiment may include an insulating plate (70). The insulating plate (70) may cover the first current collector plate (41). By covering the first current collector plate (41) on the upper surface of the first current collector plate (41), the insulating plate (70) can block the first current collector plate (41) from contacting the battery can (20), particularly the beading part (20B) of the battery can (20) described later. Additionally, the insulating plate (70) may be provided with a separate lead hole so that a lead (60) extending upward from the first current collector plate (41) can be drawn out. The lead (60) can be drawn out upward through the lead hole of the insulating plate (70) and coupled to the lower surface of the connecting plate (32) or the lower surface of the top cap (31).

[0053] The perimeter area of ​​the insulating plate (70) is interposed between the first current collector plate (41) and the beading portion (20B) of the battery can (20) to fix the combination of the electrode assembly (10) and the first current collector plate (41). Accordingly, the movement of the combination of the electrode assembly (10) and the first current collector plate (41) in the axial direction of the electrode assembly (10) is restricted, thereby improving the assembly stability of the secondary battery. The insulating plate (70) may be made of an insulating polymer resin. In one example, the insulating plate (70) may include one or more materials selected from the group consisting of polyethylene, polypropylene, polyimide, or polybutylene terephthalate.

[0054] Meanwhile, the battery can (20) according to the present embodiment may include a crimping part (20C) and a beading part (20B). The crimping part (20C) is a part of the battery can (20) that surrounds the cap assembly (30) and the gasket (50). Specifically, the battery can (20) and the cap assembly (30) may be crimped together with the gasket (50) in between. That is, a crimping connection may be applied to the connection between the battery can (20) and the cap assembly (30). Accordingly, the crimping part (20C) may be formed on the battery can (20). More specifically, the crimping connection is achieved by placing the gasket (50) between the battery can (20) and the cap assembly (30), and then bending the upper end of the battery can (20) in the direction where the cap assembly (30) is located.

[0055] The beading portion (20B) refers to a portion of the battery can (20) that is indented towards the center in an area above the electrode assembly (10) among the side portions of the battery can (20), and is intended for stable placement of the cap assembly (30) and prevention of movement of the electrode assembly (10). That is, the cap assembly (30) and the gasket (50) surrounding it according to the present embodiment can be seated on the beading portion (20B) of the battery can (20). With the cap assembly (30) and the gasket (50) surrounding it seated on the beading portion (20B), the crimping coupling described above can be performed.

[0056] The gasket (50) according to the present embodiment is positioned between the battery can (20) and the cap assembly (30) to improve the sealing performance of the secondary battery. Additionally, the gasket (50) may include an electrically insulating material and can block a short circuit from occurring between the battery can (20), which functions as a second electrode terminal (112), and the cap assembly (30), which functions as a first electrode terminal (111). This gasket (50) may include one or more materials selected from the group consisting of polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), and perfluoroalkoxyalkane (PFA).

[0057] The vent portion (110V) according to the present embodiment may be formed on the lower surface of the battery cell (110). That is, it may be formed on the bottom portion (20F, see FIG. 6) of the battery can (20).

[0058] If a thermal event or thermal runaway occurs inside a battery cell (110), high-temperature venting gas or particles may be generated. The vent section (110V) is a general term for a component or mechanism capable of discharging such high-temperature venting gas or particles. For example, a notch section (110N) with a thickness relatively thinner than the adjacent area may be formed on the bottom of the battery cell (110), specifically on the bottom of the battery can. The notch section (110N) may form a certain circumference. If the internal pressure of the battery cell (110) increases due to high-temperature venting gas generated inside the battery cell (110), the notch section (110N), which has weak rigidity due to its thin thickness, may rupture first. Due to the rupture of the notch (110N), the vent (110V) is opened, and high-temperature venting gas or particles can be discharged through the vent (110V) thus opened.

[0059] However, the structure of such a vent section (110V) is merely one example, and there are no special restrictions on the shape of the vent section (110V) as long as it is a component or mechanism capable of discharging internal venting gas during a thermal event or thermal runaway.

[0060] Meanwhile, although not specifically illustrated, the battery cell according to the present invention may be a prismatic battery cell in which an electrode assembly is housed in a prismatic can. That is, although the battery cell according to the present embodiment is depicted in the drawings as a cylindrical battery cell, this is merely one example of the structure of the battery cell of the present invention, and the battery cell according to other embodiments of the present invention may be a prismatic battery cell.

[0061] Battery cells (110) can be arranged in columns and rows within a cell frame (120), and the battery cells (110) can be electrically connected to each other via a busbar, etc., described later.

[0062] FIG. 7 is a partial perspective view of the battery assembly of FIG. 1. FIG. 8 is a cross-sectional view showing a section cut along the cutting line A-A' of FIG. 2. FIG. 9 is an enlarged partial cross-sectional view showing section “D” of FIG. 8. FIG. 10 is an enlarged partial cross-sectional view showing section “E” of FIG. 8. FIG. 11 is a cross-sectional view showing a section cut along the cutting line B-B' of FIG. 2.

[0063] Referring together to FIGS. 1 to 3 and FIGS. 7 to 11, as described above, the battery assembly (100) includes a cell frame (120) in which battery cells (110) are housed, and the cell frame (120) includes a bottom cell frame (120c) on which battery cells (110) are seated and a cover cell frame (120ab) located on the bottom cell frame (120c).

[0064] A bottom cell frame (120c) and a cover cell frame (120ab) are assembled to form an internal space, and battery cells (110) can be positioned in the internal space formed by the bottom cell frame (120c) and the cover cell frame (120ab), and a coolant (CL) can also circulate along the internal space to directly cool the battery cells (110).

[0065] The refrigerant (CL) circulates inside the cell frame (120) while in direct contact with the battery cells (110). The cell frame (120) may include an inlet port (121) through which the refrigerant (CL) flows into the interior of the cell frame (120) and an outlet port (122) through which the refrigerant is discharged to the outside of the cell frame (120). That is, the refrigerant (CL) flows into the interior of the cell frame (120) through the inlet port (121), and the refrigerant (CL) flows along the interior space of the cell frame (120) and comes into direct contact with the battery cells (110). Subsequently, the refrigerant (CL) circulating in the interior space of the cell frame (120) can be discharged to the outside of the cell frame (120) through the outlet port (122). That is, a cooling channel (300) through which the refrigerant (CL) flows may be provided inside the cell frame (120). These cooling channels (300) may have a multi-layer cooling structure, which will be described later.

[0066] The inlet port (121) and the outlet port (122) may be located on the same side of the cell frame (120) or on opposite sides. That is, there is no particular restriction on the location of the inlet port (121) and the outlet port (122) in the cell frame (120). The inlet port (121) and the outlet port (122) may be formed in the cover cell frame (120ab) of the cell frame (120).

[0067] Meanwhile, the refrigerant (CL) according to the present embodiment may be a fluid as a cooling medium. Since the refrigerant (CL) comes into direct contact with the battery cells (110) within the battery assembly (100), the refrigerant (CL) may be electrically insulated. The refrigerant (CL) may be a material having insulating properties. For example, the refrigerant (CL) may be insulating oil. However, in the case of the battery assembly (100) according to the present embodiment, general cooling water may also be used as the refrigerant (CL) because leakage of the refrigerant (CL) to the outside of the top cell frame (120a) is prevented.

[0068] FIG. 12 is a partial cross-sectional view showing an enlarged portion of “F” in FIG. 9. FIG. 13 is a partial cross-sectional view showing an enlarged portion of “G” in FIG. 10. FIG. 14 is a perspective view showing a bottom cell frame and battery cells according to an embodiment of the present invention. FIG. 15 is a plan view showing a bottom cell frame according to an embodiment of the present invention as viewed along the -z axis direction in the xy plane. FIG. 16 and FIG. 17 are cross-sectional perspective views of a bottom cell frame according to an embodiment of the present invention. In particular, FIG. 16 shows the bottom cell frame cut along the xz plane, and FIG. 17 shows the bottom cell frame cut along the yz plane.

[0069] Referring to FIGS. 8 through 17, a groove (120G) may be formed on the outer perimeter of the area where the battery cells (110) are seated in the bottom cell frame (120c). Specifically, the groove (120G) may be formed on the outer perimeter of the area where the battery cells (110) are seated when viewed along a direction perpendicular to one side of the bottom cell frame (120c). Here, viewing along a direction perpendicular to one side of the bottom cell frame (120c) means viewing the bottom cell frame (120c) along the z-axis direction or the -z-axis direction on the xy plane as in FIGS. 14 and 15, etc.

[0070] In the case of the battery assembly (100) according to the present embodiment, since an immersion cooling method using a refrigerant (CL) for direct cooling is applied, a stable waterproof sealing structure is essential to prevent the refrigerant (CL) from leaking to the outside. If the refrigerant (CL) leaks to the outside of the cell frame (120) of the battery assembly (100), the amount of refrigerant (CL) inside the cell frame (120) becomes insufficient and the circulation of the refrigerant (CL) is not properly carried out, which may lead to a decrease in cooling performance. In addition, the leaked refrigerant (CL) may have an adverse effect on other electrical components other than the battery assembly (100). The cell frame (120) is formed by assembling a bottom cell frame (120c) and a cover cell frame (120ab), and there is a risk that the refrigerant (CL) may leak through the gap between the bottom cell frame (120c) and the cover cell frame (120ab).

[0071] In the battery assembly (100) according to the present embodiment, by forming a groove (120G) on the outer perimeter of the area where the battery cells (110) are seated in the bottom cell frame (120c), the length of the waterproof interface is extended, thereby preventing the leakage of refrigerant (CL) from the gap between the bottom cell frame (120c) and the cover cell frame (120ab). The groove (120G) of the bottom cell frame (120c) can function as a primary waterproof structure.

[0072] According to the present embodiment, the cover cell frame (120ab) can be assembled into the groove (120G) of the bottom cell frame (120c). The cover cell frame (120ab) may include a rib (120R) that is engaged with the bottom cell frame (120c). FIGS. 12 and 13 illustrate that a rib (120R) is formed in the middle cell frame (120b), which is described later, among the cover cell frame (120ab). By forming the rib (120R) in the cover cell frame (120ab), leakage of refrigerant (CL) from the gap between the bottom cell frame (120c) and the cover cell frame (120ab) can be prevented. The rib (120R) of the cover cell frame (120ab) can function as an additional waterproof structure.

[0073] A rib (120R) may be formed on the outer perimeter of the area where the battery cells (110) are located within the cover cell frame (120ab). Specifically, a rib (120R) may be formed on the outer perimeter of the area where the battery cells (110) are located when viewed along a direction perpendicular to one side of the cover cell frame (120ab). Here, viewing along a direction perpendicular to one side of the cover cell frame (120ab) means viewing the cover cell frame (120ab) along the z-axis direction or the -z-axis direction on the xy plane. The rib (120R) may be provided at a position corresponding to the groove (120G).

[0074] The rib (120R) of the cover cell frame (120ab) can be engaged with the groove (120G) of the bottom cell frame (120c). Here, engaging means that the protruding shape of the rib (120R) is assembled into the recessed shape of the groove (120G). With this engaging connection, an anti-slip assembly structure can be implemented between the cover cell frame (120ab) and the bottom cell frame (120c). Through the engaging connection of the rib (120R) and the groove (120G), the assembly between the cover cell frame (120ab) and the bottom cell frame (120c) can be improved, and the length of the waterproof interface between the cover cell frame (120ab) and the bottom cell frame (120c) can be increased, thereby improving waterproof sealing performance.

[0075] In the case of the battery assembly (100) according to the present embodiment, the cell frame (120) must be able to withstand the internal pressure resulting from the circulation of the refrigerant (CL) inside. The internal pressure resulting from the circulation of the refrigerant (CL) can increase to a significant level due to the pressure required for the refrigerant (CL) to move from the inlet port (121) to the outlet port (122). If the cell frame (120) deforms and fails to withstand the internal pressure resulting from the circulation of the refrigerant (CL), the refrigerant (CL) may easily leak. Therefore, it is an important issue that the cell frame (120) withstands the internal pressure resulting from the circulation of the refrigerant (CL). In particular, the interface between the bottom cell frame (120c) and the cover cell frame (120ab) must be able to withstand this internal pressure resulting from the circulation of the refrigerant (CL). In this embodiment, an anti-slip assembly structure can be implemented by a locking connection in which the rib (120R) and the groove (120G) are joined in an alternating manner. Accordingly, the cell frame (120) can stably withstand the internal pressure resulting from the circulation of the refrigerant (CL). In particular, the internal pressure resulting from the circulation of the refrigerant (CL) can be well withstood even at the interface between the bottom cell frame (120c) and the cover cell frame (120ab).

[0076] Referring again to FIGS. 9 through 14, a waterproof adhesive (500) may be applied to the bottom cell frame (120c). At least a portion of the waterproof adhesive (500) may be located on the groove (120G). At least a portion of the waterproof adhesive (500) may be located between the bottom cell frame (120c) and the cover cell frame (120ab). There are no special restrictions on the material of the waterproof adhesive (500) as long as it exhibits waterproof performance and possesses impact resistance, adhesion, electrical insulation, etc. For example, the waterproof adhesive (500) may include a two-component epoxy-based material in which a curing agent is mixed into the main component.

[0077] In the present invention, the waterproof adhesive (500) applied on the bottom cell frame (120c) is referred to as the third waterproof adhesive (500c). The first and second waterproof adhesives (500a, 500b) will be described later. At least a portion of the third waterproof adhesive (500c) may be located on the groove (120G). Additionally, at least a portion of the third waterproof adhesive (500c) may be located between the bottom cell frame (120c) and the cover cell frame (120ab). The third waterproof adhesive (500c) can bond the bottom cell frame (120c) and the cover cell frame (120ab) to each other. Furthermore, at least a portion of the third waterproof adhesive (500c) can prevent the refrigerant (CL) from leaking through the gap between the bottom cell frame (120c) and the cover cell frame (120ab). The groove (120G) and the third waterproof adhesive (500c) can improve the sealing performance between the bottom cell frame (120c) and the cover cell frame (120ab). In particular, to maintain the sealing between the bottom cell frame (120c) and the cover cell frame (120ab), a predetermined amount of the third waterproof adhesive (500c) must be secured between the bottom cell frame (120c) and the cover cell frame (120ab). Since the groove (120G) according to the present embodiment provides a space for the third waterproof adhesive (500c) to be contained, it can help maintain the sealing between the bottom cell frame (120c) and the cover cell frame (120ab). Additionally, since the third waterproof adhesive (500c) is contained in the groove (120G), it can prevent the third waterproof adhesive (500c) from overflowing. In addition, the degree of bonding between the bottom cell frame (120c) and the cover cell frame (120ab) is improved due to the third waterproof adhesive (500c), so that the cell frame (120) can better withstand the internal pressure resulting from the circulation of the refrigerant (CL).

[0078] At least a portion of the waterproof adhesive (500) may be applied to the portion where the cover cell frame (120ab) is assembled to the groove (120G) of the bottom cell frame (120c). Additionally, at least a portion of the waterproof adhesive (500) may be applied to the portion where the rib (120R) and the groove (120G) are interlocked. In other words, at least a portion of the third waterproof adhesive (500c) may be applied to the portion where the rib (120R) of the cover cell frame (120ab) and the groove (120G) of the bottom cell frame (120c) are interlocked. Due to the interlocking of the rib (120R) and the groove (120G), the length of the waterproof interface between the cover cell frame (120ab) and the bottom cell frame (120c) is increased, and the area of ​​the region where the third waterproof adhesive (500c) is applied is increased by the length of the increased waterproof interface. That is, the third waterproof adhesive (500c) applied to the interlocking joint portion of the groove (120G) and the rib (120R) can improve the sealing performance between the bottom cell frame (120c) and the cover cell frame (120ab).

[0079] As described above, the groove (120G) itself can provide a space for the third waterproof adhesive (500c), and the rib (120R) that engages with the groove (120G) can increase the area of ​​the region where the third waterproof adhesive (500c) is applied between the cover cell frame (120ab) and the bottom cell frame (120c). Ultimately, the sealing performance between the bottom cell frame (120c) and the cover cell frame (120ab) can be increased.

[0080] Meanwhile, according to the present embodiment, a waterproof sealing structure can be achieved by providing a groove (120G) and a rib (120R) and applying a waterproof adhesive (500). Therefore, silicone rubber material components such as waterproof foam tape, sealant, and O-rings may not be required. Consequently, the manufacturing process of the battery assembly (100) is very simple and cost is reduced. However, this is an explanation of one example, and additional sealing components such as the aforementioned foam tape, sealant, and O-rings may be provided in the battery assembly as needed.

[0081] In addition, the third waterproof adhesive (500c) can securely fix the battery cells (110) on the bottom cell frame (120c).

[0082] Referring to FIGS. 4, FIGS. 5 and FIGS. 9 through 14, the third waterproof adhesive (500c) can cover the vent portion (110V) of the battery cell (110). As described above, the vent portion (110V) corresponds to a member or mechanism provided in the battery cell (110) to discharge venting gas, etc., inside the battery cell (110). The vent portion (110V) can be formed on the lower surface of the battery cell (110), and the third waterproof adhesive (500c) applied on the bottom cell frame (120c) can cover this vent portion (110V). Additionally, the third waterproof adhesive (500c) can cover a portion of the side of the battery cell (110) adjacent to the lower surface of the battery cell (110).

[0083] If a thermal event or thermal runaway occurs inside the battery cell (110), high-temperature venting gas or particles may be discharged through the open vent section (110V). Generally, when gas is ejected from the battery cell (110), pieces of electrode plates or active materials inside the battery cell (110) may be discharged to the outside while heated to a high temperature, and these high-temperature particles may appear in the form of sparks. The high-temperature venting gas or particles discharged through the vent section (110V) may tear through the bottom cell frame (120c) and be discharged to the outside of the bottom cell frame (120c). Although not specifically illustrated, the high-temperature venting gas or particles may be discharged to the outside through a separate venting channel provided below the bottom cell frame (120c).

[0084] Since the third waterproof adhesive (500c) covers the vent portion (110V) of the battery cell (110) and a portion of the side of the battery cell (110) adjacent to the bottom surface of the battery cell (110), the vent portion (110V) is not exposed. Accordingly, even if there is a thermal runaway due to an abnormality in one of the battery cells (110), high-temperature venting gas or particles are not transmitted to surrounding battery cells (110), so it is not vulnerable to chain ignition.

[0085] Additionally, the venting path of the battery cell (110) and the refrigerant (CL) can be separated from each other by the third waterproof adhesive (500c). As described above, insulating oil may be applied to the refrigerant (CL). Since insulating oil is an oil component, it can cause additional thermal runaway, ignition, and explosion when it comes into contact with venting gas or particles. The third waterproof adhesive (500c) can cover the vent section (110V) so that the vent section (110V) is not exposed to the refrigerant (CL). The third waterproof adhesive (500c) blocks high-temperature venting gas and particles discharged from the vent section (110V) of the battery cell (110) from coming into contact with the refrigerant (CL), thereby preventing thermal runaway of the battery cell (110) from leading to ignition or explosion of the entire battery assembly (100).

[0086] Referring again to FIGS. 12, 13 and FIGS. 15 through 17, the groove (120G) according to the present embodiment may extend along the outer perimeter of the area where the battery cells (110) are seated in the bottom cell frame (120c). In one embodiment, the groove (120G) may extend along the outer perimeter of the area where the battery cells (110) are seated, having a zigzag shape. When viewed along a direction perpendicular to one side of the bottom cell frame (120c), the groove (120G) may extend with a zigzag shape. Here, viewing along a direction perpendicular to one side of the bottom cell frame (120c) means viewing the bottom cell frame (120c) along the z-axis direction or the -z-axis direction on the xy plane. The rib (120R) assembled into the groove (120G) can also be connected with a zigzag shape corresponding to the shape of the groove (120G).

[0087] When the groove (120G) and the rib (120R) are interlocked, the groove (120G) and the rib (120R) are connected in a zigzag shape rather than simply in a straight line, so the anti-slip properties resulting from the interlocking connection between the groove (120G) and the rib (120R) can be further enhanced. In the parts having different slopes in the zigzag shape, the direction in which the internal pressure due to the circulation of the refrigerant (CL) acts is different from each other, so the internal pressure can be dispersed. Therefore, the groove (120G) and the rib (120R) connected in a zigzag shape can help the cell frame (120) withstand the internal pressure due to the circulation of the refrigerant (CL). However, it goes without saying that in the present invention, a structure of the groove (120G) and the rib (120R) connected in a straight line can also be applied.

[0088] Referring again to FIGS. 3, FIGS. 4, FIGS. 9 through 11, the battery assembly (100) according to the present embodiment may include a busbar frame assembly (130). The busbar frame assembly may include a busbar frame on which busbars (131) are arranged. The busbar frame assembly may include at least one busbar (131) connected to an electrode terminal. Additionally, the busbar frame assembly may include a printed circuit board. The printed circuit board is provided to sense voltage data or thermal data of the battery cells (110). For example, the printed circuit board may be connected to the electrode terminals (111, 112) of the battery cells (110) or to the busbar (131). Accordingly, voltage data of each battery cell (110) can be sensed and transmitted externally. The busbar frame assembly (130) may electrically connect the battery cells (110) in a series or parallel form.

[0089] A battery cell (110) may be provided with a first electrode terminal (111) and a second electrode terminal (112) as positive and negative electrode terminals. These first electrode terminal (111) and second electrode terminal (112) of the battery cell (110) may be provided on the upper surface of the battery cell (110). However, the location of the first electrode terminal (111) and the second electrode terminal (112) in the battery cell (110) may vary depending on the design and is not necessarily limited to the upper surface of the battery cell (110). Electrical connection between the battery cells (110) may be made by a bus bar (131) connecting the first electrode terminal (111) and the second electrode terminal (112). For example, a busbar (131) can electrically connect the first electrode terminal (111) of one battery cell (110) and the second electrode terminal (112) of another battery cell (110). In this form, a high voltage (HV) connection between battery cells (110) can be implemented. An HV connection is a connection that serves as a power source to supply power requiring high voltage, and refers to an electrical connection between battery cells or an electrical connection between a battery pack and a device.

[0091] Hereinafter, as an embodiment of the present invention, a multi-layer cooling structure of a battery assembly will be described in detail.

[0092] Referring to FIGS. 3, 8 to 13, as described above, a refrigerant (CL) is introduced into the interior of the cell frame (120) through an inlet port (121) and then discharged to the outside of the cell frame (120) through an outlet port (122). A cooling channel (300) through which the refrigerant (CL) flows is provided inside the cell frame (120). At this time, the cooling channel (300) may be a multi-layer cooling structure.

[0093] Specifically, the cooling channel (300) through which the refrigerant (CL) flows may include a first cooling channel (300a) and a second cooling channel (300b). The first cooling channel (300a) and the second cooling channel (300b) may be positioned sequentially along the height direction of the battery cell (110). Here, the height direction of the battery cell (110) refers to the direction between the upper surface and the lower surface of the battery cell (110), meaning a direction parallel to the z-axis. For example, the first cooling channel (300a) may be located above the second cooling channel (300b). The multilayer cooling structure of the cooling channel (300) mentioned in the present invention means that layered cooling channels are implemented that are distinct from each other based on the upper and lower directions of the battery cell (110).

[0094] Based on the midpoint of the battery cell (110) along the height direction of the battery cell (110), the portion of the battery cell (110) below the midpoint may be immersed in the second cooling channel (300b), and the portion of the battery cell (110) above the midpoint may be immersed in the first cooling channel (300a).

[0095] The cell frame (120) may include an inlet port (121) and an outlet port (122). The second cooling channel (300b) may be connected to the inlet port (121), and the first cooling channel (300a) may be connected to the outlet port (122). Additionally, as shown in FIG. 10, the cell frame (120) may include a connecting hole (123) connecting the first cooling channel (300a) and the second cooling channel (300b). The refrigerant (CL) may flow along the second cooling channel (300b) after being introduced through the inlet port (121). The refrigerant (CL) flowing along the second cooling channel (300b) may be introduced into the first cooling channel (300a) through the connecting hole (123). The refrigerant (CL) flowing along the first cooling channel (300a) can be discharged to the outside of the cell frame (120) through the outlet port (122). It is preferable that the first cooling channel (300a) and the second cooling channel (300b) are not connected to each other until the refrigerant (CL) reaches the connection hole (123). That is, the first cooling channel (300a) and the second cooling channel (300b) can be connected to each other only through the connection hole (123). The direction in which the refrigerant (CL) flows in the first cooling channel (300a) and the direction in which the refrigerant (CL) flows in the second cooling channel (300b) may be opposite to each other. For example, in the second cooling channel (300b) connected to the inlet port (121), the refrigerant (CL) may flow along the +y-axis direction, and in the first cooling channel (300a) connected to the outlet port (122), the refrigerant (CL) may flow along the -y-axis direction.

[0096] There is no special limitation on the number of connection holes (123), and connection holes (123) may be provided as one or multiple. Based on the location of the battery cells (110), the inlet port (121) and the outlet port (122) may be located on the same side, and the connection hole (123) may be located on the opposite side from where the inlet port (121) and the outlet port (122) are located. However, this is an exemplary structure, and the locations of the inlet port (121), the outlet port (122), and the connection hole (123) are not specifically limited.

[0097] Meanwhile, in the drawing, the cooling channel (300) is depicted as a two-layer cooling structure including a first cooling channel (300a) and a second cooling channel (300b), but there is no particular limitation on the number of cooling channels, and a cooling structure of three or more layers is also possible. That is, the cooling channel according to another embodiment of the present invention may further include a third cooling channel in addition to the first and second cooling channels along the height direction of the battery cell (110). In addition, the cooling channel may include a fourth cooling channel as needed.

[0098] Below, we will explain why the cooling channel (300) according to the present embodiment has a multi-layer cooling structure.

[0099] If the cooling channel is formed as a single layer and the refrigerant (CL) flows in only one direction, there will be a difference in the performance of the refrigerant (CL) acting on multiple battery cells (110), and cooling imbalance may occur among the battery cells (110). As a comparative example of the present invention, a single-layer cooling channel can be considered in which the inlet port and the outlet port are located on opposite sides and the refrigerant (CL) flows in only one direction. In this comparative example, the battery cell adjacent to the inlet port comes into direct contact with the refrigerant (CL), so heat dissipation occurs well, but the battery cell adjacent to the outlet port comes into contact with the refrigerant (CL) that has already been heated by the battery cells, so heat dissipation does not occur well. Therefore, cooling imbalance occurs among the battery cells (110), which may lead to a decrease in the performance of the entire battery assembly.

[0100] On the other hand, the present embodiment having a cooling channel (300) of a multi-layer cooling structure can significantly reduce the cooling variation between these battery cells (110). The key to the multi-layer cooling structure is to create a time difference in the parts of each battery cell (110) that come into contact with the refrigerant (CL) through the multi-layer cooling structure. Referring again to FIGS. 9 and 11, in the case of the battery cell (110, the leftmost battery cell in FIGS. 9 and 11) closest to the inlet port (121) and outlet port (122), the part of the battery cell (110) located in the second cooling channel (300b) comes into contact with the refrigerant (CL) first, and the part of the battery cell (110) located in the first cooling channel (300a) comes into contact with the refrigerant (CL) last. That is, in the case of the battery cell (110) closest to the inlet port (121) and outlet port (122), one part of the battery cell (110) may come into contact with the coldest refrigerant (CL) and another part of the battery cell (110) may come into contact with the hottest refrigerant (CL). On the other hand, in the case of the battery cell (110, the battery cell located furthest to the right in FIG. 10) located furthest from the inlet port (121) and outlet port (122) and closest to the connection hole (123), the part of the battery cell (110) located in the second cooling path (300b) comes into contact with the refrigerant (CL) relatively late, but this refrigerant (CL) may pass through the connection hole (123) immediately and come into contact with the part of the battery cell (110) located in the first cooling path (300a). That is, in the case of the battery cell (110) located closest to the connection hole (123), it can be interpreted that all parts of the battery cell (110) come into contact with a medium temperature refrigerant (CL). In this way, by implementing a cooling channel (300) of a multi-layer cooling structure, a difference in the order of contact with the refrigerant (CL) can be created for each part of the multiple battery cells (110).Therefore, the problem of cooling imbalance between battery cells can be resolved, thereby minimizing the cooling variation of the battery cells. As described above, in order to resolve the cooling variation between battery cells (110), in another embodiment of the present invention, a multi-layer cooling structure such as three layers, four layers, etc., beyond a two-layer cooling structure may be provided.

[0101] The cover cell frame (120ab) according to the present embodiment may include a top cell frame (120a) and a middle cell frame (120b). As one example for forming a cooling channel (300) of a multilayer cooling structure, a top cell frame (120a) and a middle cell frame (120b) may be provided. Each of the top cell frame (120a) and the middle cell frame (120b) may be a member including an upper surface and a side portion extending downward from the edge of the upper surface, and the top cell frame (120a) may be located on top of the middle cell frame (120b).

[0102] The space between the middle cell frame (120b) and the bottom cell frame (120c) can be a second cooling channel (300b), and the space between the top cell frame (120a) and the middle cell frame (120b) can be a first cooling channel (300a). An inlet port (121) can be provided in the middle cell frame (120b), and an outlet port (122) can be provided in the top cell frame (120a).

[0103] Although not specifically illustrated, it is also possible for the top cell frame (120a) and the middle cell frame (120b) to be integrated so that the cover cell frame is made of only one component.

[0104] Meanwhile, the battery cells (110) according to the present embodiment may be fitted inside the cell frame (120). For example, a plurality of holes (120h) may be formed inside the cell frame, and each of the battery cells (110) may be fixed inside the cell frame (120) by being fitted into the holes (120h).

[0105] For example, a plurality of holes (120h) of the cell frame (120) may include a top cell frame hole (120ah), a middle cell frame hole (120bh), and a bottom cell frame hole (120ch). The top cell frame hole (120ah) may be formed in the top cell frame (120a), the middle cell frame hole (120bh) may be formed in the middle cell frame (120b), and the bottom cell frame hole (120ch) may be formed in the bottom cell frame (120c).

[0106] The battery cell (110) can be mounted in the bottom cell frame hole (120ch, see FIG. 3) and seated on the bottom cell frame (120c). However, in another embodiment of the present invention, there is no separate bottom cell frame hole, and the battery cell can be seated and fixed on the bottom cell frame (120c) by a third waterproof adhesive (500c, see FIG. 14) applied to the bottom cell frame (120c).

[0107] The battery cell (110) can be mounted and secured to the middle cell frame (120b) by being inserted into the middle cell frame hole (120bh). Additionally, the battery cells (110) can be mounted and secured to the top cell frame (120a) by being inserted into the top cell frame hole (120ah).

[0108] Meanwhile, as described above, the waterproof adhesive (500) according to the present embodiment may include a third waterproof adhesive (500c) applied on the bottom cell frame (120c). Additionally, the waterproof adhesive (500) may include a first waterproof adhesive (500a) applied on the cover cell frame (120ab). Due to the first waterproof adhesive (500a) applied on the cover cell frame (120ab), the refrigerant (CL) may be prevented from leaking beyond the cover cell frame (120ab) to the upper region of the cover cell frame (120ab). With the battery cell (110) mounted in the top cell frame hole (120ah) of the cover cell frame (120ab), the first waterproof adhesive (500a) may be applied to the upper surface of the cover cell frame (120ab) and the upper region of the battery cell (110).

[0109] As previously explained, electrical connection between battery cells (110) can be made by a bus bar (131) connecting the first electrode terminal (111) and the second electrode terminal (112). Electrical connection by the bus bar (131) can be made at the top of the cover cell frame (120ab). The bus bar (131) can be located at the top of the cover cell frame (120ab) and also at the top of the top cell frame (120a) of the cover cell frame (120ab).

[0110] At least a portion of the busbar (131) may be surrounded by the first waterproof adhesive (500a). Additionally, the surrounding space of the busbar (131) may be filled with the first waterproof adhesive (500a). Additionally, the first electrode terminal (111) and the second electrode terminal (112) of the battery cell (110) may be surrounded by the first waterproof adhesive (500a). Additionally, the gap between the top cell frame hole (120ah) and the battery cell (110) fitted therein may be filled with the first waterproof adhesive (500a). Due to the first waterproof adhesive (500a), the refrigerant (CL) may be prevented from leaking into the upper region of the cover cell frame (120ab). In the battery assembly (100), the waterproof sealing structure at the top thereof may be implemented by the first waterproof adhesive (500a).

[0111] The refrigerant (CL) may be insulating oil or cooling water. If the refrigerant (CL), which is cooling water, comes into contact with the HV connection part, a short circuit may occur, causing serious safety issues. Furthermore, even if the refrigerant (CL) is insulating oil, if the refrigerant (CL) comes into contact with the part where the electrical connections of the battery cells (110) are made, it may adversely affect the electrical connections of the battery cells (110). Accordingly, in this embodiment, the influence of the refrigerant (CL) on the electrical connections of the battery cells (110) can be minimized by the first waterproof adhesive (500a) applied to the upper part of the cover cell frame (120ab).

[0112] The waterproof adhesive (500) may include a second waterproof adhesive (500b) applied to the middle cell frame (120b) among the cover cell frames (120ab). As described above, in the cooling channel (300) of the multi-layer cooling structure, it is preferable that the first cooling channel (300a) and the second cooling channel (300b) are not connected to each other until the refrigerant (CL) reaches the connection hole (123). That is, the first cooling channel (300a) and the second cooling channel (300b) can be connected to each other only through the connection hole (123). This is because it creates a difference in the order of contact with the refrigerant (CL) for each part of the multiple battery cells (110) and reduces the cooling variation of the battery cells. The second waterproof adhesive (500b) can prevent the refrigerant (CL) of the first cooling channel (300a) from moving to the second cooling channel (300b) or the refrigerant (CL) of the second cooling channel (300b) from moving to the first cooling channel (300a) in the portion excluding the connection hole (123). A waterproof airtight structure between the first cooling channel (300a) and the second cooling channel (300b), excluding the connection hole (123), can be formed by the second waterproof adhesive (500b). The gap between the middle cell frame hole (120bh) and the battery cell (110) fitted therein can be filled with the second waterproof adhesive (500b).

[0114] Meanwhile, the middle cell frame (120b) and the top cell frame (120a) may have a structure of grooves and ribs. This may be a structure similar to the groove (120G) formed in the bottom cell frame (120c) described earlier and the rib (120R) that engages with it. This will be explained in detail below.

[0115] A groove (120G) may be formed on the outer perimeter of the area where the battery cells (110) are located within the middle cell frame (120b). Specifically, when viewed along a direction perpendicular to one side of the middle cell frame (120b), a groove (120G) may be formed on the outer perimeter of the area where the battery cells (110) are located.

[0116] By forming a groove (120G) on the outer perimeter of the area where the battery cells (110) are located in the middle cell frame (120b), it is possible to prevent the refrigerant (CL) from leaking from the gap between the middle cell frame (120b) and the top cell frame (120a). The groove (120G) of the middle cell frame (120b) can function as a primary waterproof structure.

[0117] The top cell frame (120a) can be assembled into the groove (120G) of the middle cell frame (120b). Additionally, the top cell frame (120a) may include a rib (120R) that engages with the middle cell frame (120b). FIGS. 12 and 13 illustrate the formation of a rib (120R) on the top cell frame (120a). By forming a rib (120R) on the top cell frame (120a), leakage of refrigerant (CL) from the gap between the middle cell frame (120b) and the top cell frame (120a) can be prevented. The rib (120R) of the top cell frame (120a) can function as an additional waterproof structure.

[0118] The rib (120R) can be formed on the outer perimeter of the area where the battery cells (110) are located in the top cell frame (120a). Specifically, the rib (120R) can be formed on the outer perimeter of the area where the battery cells (110) are located when viewed along a direction perpendicular to one side of the top cell frame (120a).

[0119] The rib (120R) of the top cell frame (120a) can be engaged with the groove (120G) of the middle cell frame (120b). As described above, engaging means that the protruding shape of the rib (120R) is assembled to the recessed shape of the groove (120G). With this engaging connection, an anti-slip assembly structure can be implemented between the top cell frame (120a) and the middle cell frame (120b). Through the engaging connection of the rib (120R) and the groove (120G), the length of the waterproof interface between the top cell frame (120a) and the middle cell frame (120b) is increased, thereby improving waterproof sealing performance.

[0120] An anti-slip assembly structure can be implemented by an interlocking connection in which the ribs (120R) and grooves (120G) are joined in an alternating manner, not only between the bottom cell frame (120c) and the cover cell frame (120ab), but also between the top cell frame (120a) and the middle cell frame (120b) of the cover cell frame (120ab). Accordingly, the internal pressure resulting from the circulation of the refrigerant (CL) at the interface between the top cell frame (120a) and the middle cell frame (120b) can be well withstood, and leakage of the refrigerant (CL) can be prevented.

[0121] Meanwhile, as previously explained, a second waterproof adhesive (500b) may be applied to the middle cell frame (120b). At least a portion of the second waterproof adhesive (500b) may be located on the groove (120G) of the middle cell frame (120b). At least a portion of the second waterproof adhesive (500b) may be located between the middle cell frame (120b) and the top cell frame (120a). The second waterproof adhesive (500b) can bond the middle cell frame (120b) and the top cell frame (120a) together. Additionally, at least a portion of the second waterproof adhesive (500b) can prevent the refrigerant (CL) from leaking through the gap between the middle cell frame (120b) and the top cell frame (120a). The groove (120G) and the second waterproof adhesive (500b) can improve the sealing performance between the middle cell frame (120b) and the top cell frame (120a). In particular, to maintain the sealing between the middle cell frame (120b) and the top cell frame (120a), a predetermined amount of the second waterproof adhesive (500b) must be secured between the middle cell frame (120b) and the top cell frame (120a). According to the present embodiment, the groove (120G) formed in the middle cell frame (120b) provides a space for the second waterproof adhesive (500b) to be contained, and thus can help maintain the sealing between the middle cell frame (120b) and the top cell frame (120a). In addition, the degree of bonding between the middle cell frame (120b) and the top cell frame (120a) is improved due to the second waterproof adhesive (500b), so that the cell frame (120) can better withstand the internal pressure resulting from the circulation of the refrigerant (CL).

[0122] At least a portion of the second waterproof adhesive (500b) can be applied to the portion where the rib (120R) of the top cell frame (120a) and the groove (120G) of the middle cell frame (120b) are joined. Due to the joining of the rib (120R) and the groove (120G), the length of the waterproof interface between the top cell frame (120a) and the middle cell frame (120b) is increased, and the area of ​​the region where the second waterproof adhesive (500b) is applied is increased by the length of the increased waterproof interface. That is, the second waterproof adhesive (500b) applied to the joined portion of the groove (120G) and the rib (120R) can improve the sealing performance between the top cell frame (120a) and the middle cell frame (120b).

[0123] As described above, the groove (120G) of the middle cell frame (120b) itself can provide a space for the second waterproof adhesive (500b), and the rib (120R) of the top cell frame (120a) which is engaged with the groove (120G) can increase the area of ​​the region where the second waterproof adhesive (500b) is applied between the middle cell frame (120b) and the top cell frame (120a). Ultimately, the sealing performance between the middle cell frame (120b) and the top cell frame (120a) can be increased.

[0124] FIG. 18 is a cross-sectional view showing a cross section cut along the cutting line H-H' of FIG. 2. FIG. 19 is a partial cross-sectional view showing an enlarged view of the “I” portion of FIG. 19. FIG. 20 is a perspective view of a cover cell frame according to an embodiment of the present invention. FIG. 21 is a plan view showing the cover cell frame of FIG. 20 viewed along the +z-axis direction in the xy-plane.

[0125] Referring to FIGS. 2, FIGS. 11, and FIGS. 18 through 21, in one embodiment of the present invention, a spacer (600a) is formed on at least one side of the bottom cell frame (120c) or one side of the cover cell frame (120ab) facing each other between the bottom cell frame (120c) and the cover cell frame (120ab). The spacer (600a) protrudes along a direction perpendicular to the said side of the bottom cell frame (120c) or the said side of the cover cell frame (120ab). That is, in one embodiment, a spacer may be formed on either one side of the bottom cell frame (120c) or one side of the cover cell frame (120ab) facing each other. In addition, in another embodiment, spacers may be formed on both the side of the bottom cell frame (120c) and the side of the cover cell frame (120ab) facing each other.

[0126] One side of the bottom cell frame (120c) and one side of the cover cell frame (120ab) facing each other may refer to parts corresponding to the gap between the bottom cell frame (120c) and the cover cell frame (120ab). Meanwhile, the spacer (600a) may be in a shape that protrudes along the height direction. Here, the height direction of the battery cell (110) refers to the direction between the upper surface and the lower surface of the battery cell (110), as described above, and means a direction parallel to the z-axis.

[0127] FIGS. 19 to 21 illustrate, as an embodiment of the present invention, a spacer (600a) is formed on one side of the cover cell frame (120ab) that faces each other between the bottom cell frame (120c) and the cover cell frame (120ab). The spacer (600a) formed on the one side of the cover cell frame (120ab) may protrude toward the bottom cell frame (120c). The spacer (600a) formed on the one side of the cover cell frame (120ab) may be formed on the middle cell frame (120b) of the cover cell frame (120ab). The spacer (600a) may be provided on one side of the middle cell frame (120b) that faces the bottom cell frame (120c).

[0128] During the process of assembling the bottom cell frame (120c) and the cover cell frame (120ab), the gap between the bottom cell frame (120c) and the cover cell frame (120ab) can be sealed by the spacer (600a). That is, the spacer (600a) according to the present embodiment blocks the gap between the cover cell frame (120ab) and the bottom cell frame (120c), thereby preventing the refrigerant (CL) from leaking from the gap between the bottom cell frame (120c) and the cover cell frame (120ab).

[0129] The spacer (600a) may be compressed by the force with which the bottom cell frame (120c) and the cover cell frame (120ab) are assembled. Due to the force with which the bottom cell frame (120c) and the cover cell frame (120ab) are assembled, the spacer (600a) is compressed along the height direction, and its shape may collapse. During the molding process, there may be differences in flatness in some areas of each bottom cell frame (120c) and the cover cell frame (120ab). Depending on the flatness of each bottom cell frame (120c) and the cover cell frame (120ab), there may be areas where a large gap occurs between the bottom cell frame (120c) and the cover cell frame (120ab), and there is a risk of refrigerant (CL) leaking through the gap. In this embodiment, the spacer (600a) is designed to be pressed along the height direction and collapse in shape as the bottom cell frame (120c) and the cover cell frame (120ab) are assembled. Through this spacer (600a), gaps that occur according to the flatness of each of the bottom cell frame (120c) and the cover cell frame (120ab) can be corrected and sealed, thereby ultimately preventing the risk of refrigerant (CL) leakage. Even without a separate gasket member being interposed, the spacer (600a) according to this embodiment can perform a function similar to a gasket. Furthermore, if the interlocking connection of the rib (120R) and groove (120G) described above is additionally applied to the structure of the spacer (600a), uniformity of the sealing to prevent refrigerant leakage can be secured.

[0130] A spacer (600a) may be positioned on the outer perimeter of the area where the battery cells (110) are seated in the cell frame (120). Additionally, the spacer (600a) may extend along the outer perimeter of the area where the battery cells (110) are seated in the cell frame (120). When viewed along a direction perpendicular to one side of the bottom cell frame (120c) or one side of the cover cell frame (120ab), the spacer (600a) may be formed on the outer perimeter of the area where the battery cells (110) are located. Here, viewing along a direction perpendicular to one side of the bottom cell frame (120c) or one side of the cover cell frame (120ab) means viewing the bottom cell frame (120c) or the cover cell frame (120ab) along the z-axis direction or the -z-axis direction on the xy plane. FIGS. 20 and 21 illustrate a form in which a spacer (600a) provided on one side of a cover cell frame (120ab) extends along the outer perimeter of the area where the battery cells (110) are seated. In particular, the spacer (600a) provided on one side of the cover cell frame (120ab) extends along the outer perimeter of the middle cell frame hole (120bh) into which the battery cells are fitted. As previously described, a structure to prevent refrigerant (CL) leakage in the cell frame (120) can be implemented by extending the spacer (600a) for correcting gaps caused by the flatness of the bottom cell frame (120c) and the cover cell frame (120ab) along the outer perimeter of the area where the battery cells (110) are located. However, in the present invention, a form in which the spacer (600a) extends partially along the outer perimeter of the area where the battery cells (110) are located is also possible.

[0131] The spacer (600a) may be connected in a zigzag shape along the outer perimeter of the area where the battery cells (110) are seated. Because the spacer (600a) is connected in a zigzag shape, it can better withstand the internal pressure of the refrigerant (CL) between the bottom cell frame (120c) and the cover cell frame (120ab). However, it goes without saying that in the present invention, a structure of the spacer (600a) connected in a straight line can also be applied.

[0132] Meanwhile, referring to FIGS. 7, 9, 11, 12, and 20 together, the bottom cell frame (120c) and the cover cell frame (120ab) according to the present embodiment can be joined by a bolt member (700). For example, each of the bottom cell frame (120c) and the cover cell frame (120ab) may include a protruding portion protruding in a direction parallel to the xy plane, and the bottom cell frame (120c) and the cover cell frame (120ab) can be joined to each other by a bolt member (700) that passes through all of each other's protruding portions. In one embodiment, it is possible for the bolt member (700) to be joined with a separate nut member, and in another embodiment, it is possible for the bolt member (700) to pass through either the bottom cell frame (120c) or the cover cell frame (120ab) and then be screw-coupled to a fastening hole formed in the other of the bottom cell frame (120c) and the cover cell frame (120ab). Since the bottom cell frame (120c) and the cover cell frame (120ab) are joined by a bolt member (700), the fixing force between the bottom cell frame (120c) and the cover cell frame (120ab) is increased, and the bottom cell frame (120c) and the cover cell frame (120ab) can be firmly assembled. In particular, the fastening force by the bolt member (700) between the bottom cell frame (120c) and the cover cell frame (120ab) can correspond to the force that assembles the bottom cell frame (120c) and the cover cell frame (120ab), that is, the force that presses the spacer (600a). As the spacer (600a) is pressed along the height direction, the gap between the bottom cell frame (120c) and the cover cell frame (120ab) can be corrected as described above, and refrigerant leakage between the bottom cell frame (120c) and the cover cell frame (120ab) can be prevented, thereby improving sealing performance.However, the bolt member (700) is merely an example structure for assembling the bottom cell frame (120c) and the cover cell frame (120ab), and it goes without saying that other methods may be applied to the assembly between the bottom cell frame (120c) and the cover cell frame (120ab).

[0133] Additionally, the middle cell frame (120b) and the top cell frame (120a) can also be joined by a bolt member (700). For example, each of the middle cell frame (120b) and the top cell frame (120a) may include a protruding portion protruding in a direction parallel to the xy plane, and the middle cell frame (120b) and the top cell frame (120a) can be joined by a bolt member (700) that passes through all of each other's protruding portions. In one embodiment, it is possible for the bolt member (700) to be joined with a separate nut member, and in another embodiment, it is possible for the bolt member (700) to pass through either the middle cell frame (120b) or the top cell frame (120a) and then be screw-fastened into a fastening hole formed in the other of the middle cell frame (120b) and the top cell frame (120a). Since the middle cell frame (120b) and the top cell frame (120a) are joined by a bolt member (700), the fixing force between the middle cell frame (120b) and the top cell frame (120a) is increased, and refrigerant leakage between the middle cell frame (120b) and the top cell frame (120a) is prevented, thereby improving sealing performance.

[0135] Meanwhile, the width of the spacer (600a) according to the present embodiment may be 0.3 mm or more and 2.0 mm or less. Here, the width of the spacer (600a) may correspond to the length of the spacer (600a) along a direction parallel to the one surface of the bottom cell frame (120c) or the one surface of the cover cell frame (120ab). That is, in FIG. 19, the width of the spacer (600a) may correspond to the length of the spacer (600a) along a direction parallel to the x-axis. If the width of the spacer (600a) is less than 0.3 mm, there is a problem that it is difficult to implement such a spacer (600a) during the process of forming the bottom cell frame (120c) or the cover cell frame (120ab) because the width of the spacer (600a) is too narrow. Additionally, if the width of the spacer (600a) exceeds 2.0 mm, the width of the spacer (600a) is excessively wide, and there may be difficulty in filling the gaps that occur according to the flatness of the bottom cell frame (120c) and the cover cell frame (120ab) respectively.

[0136] Meanwhile, the protrusion height of the spacer (600a) according to the present embodiment may be 0.03 mm or more and 0.15 mm or less. Here, the protrusion height of the spacer (600a) may correspond to the degree of protrusion of the spacer (600a) in a direction perpendicular to the one surface of the bottom cell frame (120c) or the one surface of the cover cell frame (120ab). That is, in FIG. 19, the protrusion height of the spacer (600a) may correspond to the protruding length of the spacer (600a) in a direction parallel to the z-axis. If the protrusion height of the spacer (600a) is less than 0.03 mm, it may be difficult for the spacer (600a) to fill the gap that occurs according to the flatness of the bottom cell frame (120c) and the cover cell frame (120ab), respectively. In addition, if the protrusion height of the spacer (600a) exceeds 0.15 mm, the spacer (600a) is excessively protruded, making it difficult to seal the gap between the bottom cell frame (120c) and the cover cell frame (120ab), and there may be a problem where the overall height of the battery assembly (100) increases, thereby reducing space utilization.

[0138] FIG. 22 is a cross-sectional view showing a cross-section according to another embodiment of the present invention. In a battery assembly according to another embodiment of the present invention, a cross-section at the same location as in FIG. 19 is shown in FIG. 22.

[0139] Referring to FIG. 22, as another embodiment of the present invention, a spacer (600b) is formed on one side of the bottom cell frame (120c) or one side of the cover cell frame (120ab) facing each other between the bottom cell frame (120c) and the cover cell frame (120ab). The spacer (600b) formed on the one side of the bottom cell frame (120c) may protrude toward the cover cell frame (120ab). The spacer (600b) formed on the one side of the bottom cell frame (120c) may protrude in a direction opposite to the direction in which the spacer (600a) formed on the cover cell frame (120ab) shown in FIG. 19 protrudes. The spacer (600b) formed on the above-mentioned surface of the bottom cell frame (120c) can perform the same or similar function as the spacer (600a) formed on the cover cell frame (120ab) described above, and a detailed explanation thereof is omitted as it would be redundant.

[0140] FIG. 23 is a cross-sectional view showing a cross section according to another embodiment of the present invention.

[0141] Referring to FIG. 23, as another embodiment of the present invention, a spacer (600a, 600b) may be formed on at least one side of the bottom cell frame (120c) or one side of the cover cell frame (120ab) facing each other between the bottom cell frame (120c) and the cover cell frame (120ab).

[0142] However, a bottom plate (120d) may be additionally positioned between the bottom cell frame (120c) and the cover cell frame (120ab). The bottom plate (120d) may be a component for forming a venting space through which venting gas or particles discharged from the vent portion (110V) of the battery cell (110) can move. A venting space, which is a predetermined space, may be provided between the bottom plate (120d) and the bottom cell frame (120c). Venting gas or particles discharged from the vent portion (110V) of the battery cell (110) may flow into the venting space while tearing a part of the bottom plate (120d). Venting gas or particles may flow along the venting space and be discharged to the outside of the battery pack through a venting device provided at the end of the venting space. The bottom plate (120d) may have a notch formed in a portion corresponding to the vent portion (110V) of the battery cell (110) so that it can be easily torn by venting gas or particles.

[0143] A spacer (600b) formed on one side of the bottom cell frame (120c) may protrude toward the cover cell frame (120ab), and a spacer (600a) formed on one side of the cover cell frame (120ab) may protrude toward the bottom cell frame (120c). At this time, each of the spacer (600b) formed on one side of the bottom cell frame (120c) and the spacer (600a) formed on one side of the cover cell frame (120ab) may face the bottom plate (120d) and come into contact with the bottom plate (120d).

[0145] FIG. 24 is a cross-sectional perspective view of a middle cell frame according to one embodiment of the present invention.

[0146] Referring together to FIGS. 16, 17, and 24, the groove (120G) formed in the bottom cell frame (120c) may extend along the outer perimeter of the area where the battery cells (110) are seated in the bottom cell frame (120c). As previously described, for example, the groove (120G) may extend in a zigzag shape along the outer perimeter of the area where the battery cells (110) are seated. The rib (120R) of the cover cell frame assembled to the groove (120G) of the bottom cell frame (120c) may also extend along the outer perimeter of the area where the battery cells (110) are seated. In particular, a rib (120R) may be formed on the middle cell frame (120b) among the cover cell frames, and this rib (120R) may also be connected in a zigzag shape corresponding to the shape of the groove (120G) of the bottom cell frame (120c). The effect regarding connecting in a zigzag shape is redundant with the previously explained content and is therefore omitted. Meanwhile, FIG. 24 shows that a middle cell frame hole (120bh) into which battery cells are fitted is formed in the middle cell frame (120b).

[0148] FIG. 25 is an exploded perspective view showing a third waterproof adhesive and a bottom cell frame according to one embodiment of the present invention.

[0149] Referring to FIG. 25, a bottom cell frame (120c) and a third waterproof adhesive (500c) applied thereon are shown. By the third waterproof adhesive (500c) applied on the bottom cell frame (120c), the battery cells can be seated and fixed on the bottom cell frame (120c), the leakage of refrigerant in the downward direction of the battery cells can be prevented, and the high-temperature venting gas and particles discharged from the vent portion of the battery cell can be blocked from coming into contact with the refrigerant.

[0150] FIG. 26 is an exploded perspective view showing a second waterproof adhesive and a middle cell frame according to one embodiment of the present invention.

[0151] Referring to FIG. 26, a middle cell frame (120b) and a second waterproof adhesive (500b) applied thereon are illustrated. A middle cell frame hole (120bh) may be formed in the middle cell frame (120b), and a battery cell may be fitted into the middle cell frame hole (120bh) and mounted and fixed to the middle cell frame (120b). By the second waterproof adhesive (500b) applied on the middle cell frame (120b), the degree of bonding between the middle cell frame (120b) and the top cell frame (120a) may be improved, and leakage of refrigerant through the gap between the middle cell frame hole (120bh) and the battery cell fitted therein may be prevented.

[0152] FIG. 27 is an exploded perspective view showing a first waterproof adhesive and a top cell frame according to one embodiment of the present invention.

[0153] Referring to FIG. 27, a top cell frame (120a) and a first waterproof adhesive (500a) applied thereon are illustrated. A top cell frame hole (120ah) may be formed in the top cell frame (120a), and a battery cell may be fitted into the top cell frame hole (120ah) and mounted and fixed to the top cell frame (120a). By the first waterproof adhesive (500a) applied on the top cell frame (120a), leakage of refrigerant in the upward direction of the battery cells may be prevented.

[0154] Meanwhile, referring again to FIG. 11, the cell frame (120) according to the present embodiment may include a distribution mechanism (200), and the distribution mechanism (200) may include an inlet distribution mechanism (210) disposed adjacent to the inlet port (121). The inlet distribution mechanism (210) may be provided between the inlet port (121) and the battery cells (110).

[0155] The inlet distribution mechanism (210) may include a bulkhead and a plurality of distribution holes formed in the bulkhead. These distribution holes may be positioned to correspond to the rows in which the battery cells are arranged. The refrigerant (CL) introduced through the inlet port (121) may not enter the space where the battery cells are located directly, but may be introduced into the space where the battery cells are located after being distributed through the distribution holes. Accordingly, the refrigerant (CL) may not be concentrated on only some of the large number of battery cells (110), but may flow evenly distributed over all of the battery cells (110). Therefore, uniform cooling of all of the battery cells (110) becomes possible, which can lead to an improvement in the performance of the battery assembly.

[0156] Additionally, although not specifically illustrated, the distribution mechanism (200) may include an outlet distribution mechanism positioned adjacent to the outlet port (122). The outlet distribution mechanism may be provided between the outlet port (122) and the battery cells (110). The outlet distribution mechanism may also include a partition and a plurality of distribution holes formed in the partition. Similar to the inlet distribution mechanism (210), the outlet distribution mechanism may also be responsible for the function of inducing the refrigerant (CL) to flow evenly distributed across all the battery cells (110).

[0158] Meanwhile, referring again to FIG. 1, the battery assembly (100) according to one embodiment of the present invention illustrated in FIG. 1 can be mounted directly onto a vehicle or chassis. That is, in the case of the battery assembly (100) according to the present embodiment, the battery cells (110) can be mounted directly onto a vehicle or chassis with the battery cells housed in a cell frame (120). The inlet port (121) and outlet port (122) of the cell frame (120) can be connected to a refrigerant circulation system within the vehicle.

[0159] FIGS. 28 and FIGS. 29 are exploded perspective views of a battery pack according to one embodiment of the present invention.

[0160] Referring to FIGS. 1, 28 and 29, a battery pack (1000) according to another embodiment of the present invention may include at least one battery assembly (100); a pack frame (1100) that accommodates at least one battery assembly (100) and has one side open; and a pack cover (1200) that covers the open side of the pack frame (1100). FIGS. 22 and 23 illustrate, as an example, that three battery assemblies (100) are accommodated in the pack frame (1100).

[0161] The pack frame (1100) may include a bottom portion (1110) and a side beam (1120). At least one battery assembly (100) may be placed on the bottom portion (1110). The side beam (1120) may extend along the edge of the bottom portion (1110) and extend in a direction perpendicular to one side of the bottom portion (1110). By the bottom portion (1110) and the side beam (1120), an internal space with an open top may be provided, and the battery assembly (100) may be housed in this internal space. The pack cover (1200) may cover the upper surface of the battery assembly (100) mounted on the pack frame (1100).

[0162] Meanwhile, the battery pack (1000) according to the present embodiment may include a filling member (1300) foamed in the space within the pack frame (1100) and the pack cover (1200). The filling member (1300) according to the present embodiment may be a foamed member. The filling member (1300) may be a foamed member that is foamed after being filled in the space within the pack frame (1100) and the pack cover (1200).

[0163] The filling member (1300) according to the present embodiment may be formed of a resin. For example, the filling members (1300) may be formed of resin or the like. The filling member (1300) may include an air pocket, and an adhesive may be provided in the air pocket. The filling member (1300) may be foamed rubber, i.e., cellular or sponge. The filling member (1300) may include an air-filled matrix structure. The filling member (1300) may be based, for example, silicone, polyurethane, or other organic materials.

[0164] The filling member (1300) can be foamed into a plate shape by, for example, applying it onto a pack frame (1100) or by using a spray. The filling member (1300) may include a foaming promoter.

[0165] When the filling member (1300) comes into contact with other components, it subsequently hardens and combines with the other components to provide fixed support. Thus, the adhesive force between the components that the filling member (1300) comes into contact with can be strengthened. In this embodiment, the adhesive force between the pack frame (1100), the pack cover (1200), and the battery assembly (100) can be strengthened by the filling member (1300). Additionally, the filling member (1300) can absorb vibrations and shocks applied to the battery pack (1000), so that the components within the battery pack (1000) do not separate or detach, thereby improving the safety and mechanical reliability of the battery pack.

[0166] Meanwhile, the battery pack (1000) according to the present embodiment may include an inlet pipe (1400) connected to an inlet port (121) of the battery assembly (100) and an outlet pipe (1500) connected to an outlet port (122) of the battery assembly (100).

[0167] Each of the inlet pipe (1400) and the outlet pipe (1500) can pass through the side beam (1120) and be connected to the inlet port (121) and outlet port (122) of the battery assembly (100). Additionally, the inlet pipe (1400) and the outlet pipe (1500) can be connected to a refrigerant circulation system inside the vehicle. Refrigerant supplied by the refrigerant circulation system inside the vehicle passes through the inlet pipe (1400) and reaches the inlet port (121). Refrigerant that circulates inside the battery assembly (100) and is discharged through the outlet port (122) is returned to the refrigerant circulation system through the outlet pipe (1500).

[0168] 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 position of the observer.

[0169] One or more battery assemblies 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.

[0170] The above battery assembly 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, or to Energy Storage Systems (ESS), but is not limited thereto and can be applied to various devices capable of using secondary batteries.

[0171] 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. Explanation of the symbols

[0172] 100: Battery assembly 110: Battery cell 120: Cell Frame 120ab: Cover cell frame 120c: Bottom cell frame 120G: Groove 120R: Rib 600a, 600b: Spacers

Claims

Claim 1 A battery assembly comprising: a plurality of battery cells; and a cell frame in which the battery cells are housed; wherein the cell frame comprises a bottom cell frame on which the battery cells are seated and a cover cell frame located on the bottom cell frame, wherein a refrigerant circulates inside the cell frame while in direct contact with the battery cells, and between the bottom cell frame and the cover cell frame, a spacer is formed on at least one of one side of the bottom cell frame or one side of the cover cell frame facing each other, wherein the spacer protrudes along a direction perpendicular to the one side of the bottom cell frame or the one side of the cover cell frame, and wherein the spacer is located in an area outside the region in which the battery cells are seated in the cell frame. Claim 2 In claim 1, the battery assembly is in the form of a spacer protruding along the height direction. Claim 3 In claim 1, the spacer formed on one surface of the bottom cell frame is a battery assembly protruding toward the cover cell frame. Claim 4 In claim 1, the spacer formed on one surface of the cover cell frame is a battery assembly protruding toward the bottom cell frame. Claim 5 A battery assembly according to claim 1, wherein the spacer is pressed by the force with which the bottom cell frame and the cover cell frame are assembled. Claim 6 A battery assembly according to claim 1, wherein the gap between the bottom cell frame and the cover cell frame is sealed by the spacer. Claim 7 delete Claim 8 A battery assembly according to claim 1, wherein the spacer extends along the outer perimeter of the area where the battery cells are seated in the cell frame. Claim 9 In claim 1, the bottom cell frame and the cover cell frame are joined by a bolt member to form a battery assembly. Claim 10 A battery assembly according to claim 1, wherein a groove is formed on the outer perimeter of the area where the battery cells are seated in the bottom cell frame. Claim 11 A battery assembly in which the cover cell frame is assembled into the groove of the bottom cell frame in claim 10. Claim 12 In claim 11, a battery assembly wherein a waterproof adhesive is applied to the bottom cell frame, and at least a portion of the waterproof adhesive is applied to the portion where the cover cell frame is assembled to the groove of the bottom cell frame. Claim 13 In claim 1, the battery assembly comprises a cover cell frame having a rib that is engaged with the bottom cell frame. Claim 14 In claim 1, the cell frame comprises a battery assembly including an inlet port through which the refrigerant flows into the cell frame and an outlet port through which the refrigerant is discharged to the outside of the cell frame. Claim 15 In claim 1, the battery cells are in the form of a battery assembly fitted inside the cell frame. Claim 16 In paragraph 1, the battery assembly wherein the refrigerant is insulating oil or cooling water. Claim 17 A battery assembly according to claim 1, wherein the battery cells are housed in the cell frame and are mounted directly to a vehicle or chassis. Claim 18 A battery pack comprising: a battery assembly according to claim 1; a pack frame housing the battery assembly and having one side open; and a pack cover covering the open side of the pack frame.

Images