Battery assembly and device including same

Abstract

A battery assembly according to one embodiment of the present invention includes a battery cell stack in which a plurality of battery cells are stacked, a frame in which the battery cell stack is housed and which includes a first side portion, a second side portion, a ceiling portion, and a bottom portion, and an inlet and an outlet for circulating a coolant within the frame. The coolant flows into the frame through the inlet and is discharged through the outlet. A pad member is disposed at at least one location between the plurality of battery cells, and at least one of the pad members extends from the ceiling portion to the bottom portion of the frame.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of priority based on Korean Patent Application No. 10-2023-0159673 filed on November 17, 2023 and Korean Patent Application No. 10-2024-0161140 filed on November 13, 2024, and all contents disclosed in the documents of these Korean patent applications are incorporated herein by reference.

[0002] The present invention relates to a battery assembly and a device including the same, and more particularly to a battery assembly and a device including the same with improved cooling efficiency and safety. [Background technology]

[0003] With technological development and increasing demand for mobile devices, the demand for secondary batteries as an energy source is rapidly increasing. As a result, much research is being conducted on secondary batteries that can meet various requirements.

[0004] Secondary batteries have attracted much attention as energy sources for power plants such as electric bicycles, electric vehicles, and hybrid electric vehicles, as well as for mobile devices such as mobile phones, digital cameras, and laptop computers.

[0005] Recently, as the need for large-capacity secondary battery structures has increased, including the use of secondary batteries as energy storage sources, there has been an increasing demand for battery packs with medium to large modular structures that assemble battery modules in which multiple secondary batteries are connected in series / parallel.

[0006] On the other hand, when connecting multiple battery cells in series / parallel to form a battery pack, a common method is to form a battery module consisting of at least one battery cell, and then use the at least one battery module to add other components to form a battery pack.

[0007] Because the battery cells that make up such medium- to large-sized battery modules are composed of rechargeable secondary batteries, such high-power, large-capacity secondary batteries generate a large amount of heat during the charging and discharging process. In this case, the heat generated from the multiple battery cells may be combined in a small space, causing a rapid and intense rise in temperature. In other words, a battery module in which multiple battery cells are stacked and a battery pack equipped with such a battery module can produce high power output, but it is difficult to remove the heat generated by the battery cells during charging and discharging. If the battery cells do not properly dissipate heat, the battery cells will deteriorate more quickly, their lifespan will be shortened, and the risk of explosion or fire will increase.

[0008] Furthermore, battery modules included in vehicle battery packs are often exposed to direct sunlight and high temperatures, such as in summer or desert regions. Furthermore, because multiple battery modules are closely packed together to increase a vehicle's driving range, flames or heat generated in one battery module can easily spread to adjacent battery modules, ultimately leading to the battery pack itself catching fire or exploding.

[0009] Furthermore, battery packs are heavy because they are made up of a combination of multiple battery modules, making them unsuitable for loading multiple batteries onto vehicles such as automobiles, and there is a need to improve the energy density.

[0010] FIG. 1 is a cross-sectional view showing a cross section of a battery pack including a conventional battery module.

[0011] 1, a conventional battery module 1 includes a battery cell stack 3 including battery cells 2 stacked in a predetermined direction, and a module frame 4 that houses the battery cell stack 3. A thermally conductive resin layer 5 may be provided between the battery cell stack 3 and the bottom of the module frame 4. The battery cell stack 3 is fixed and positioned on the thermally conductive resin layer 5. In this case, a heat sink 6 may be provided below the bottom of the module frame 4 to cool heat generated by the battery cell stack 3. A cooling channel through which a refrigerant such as cooling water flows may be formed inside the heat sink 6.

[0012] However, the heat sink 6 has the disadvantage of not being very efficient at cooling because it does not receive heat from direct contact with the battery cell stack 3. In particular, air gaps are formed between the bottom of the module frame 4 and the thermally conductive resin layer 5, and between the bottom of the module frame 4 and the heat sink 6, and these air gaps hinder heat transfer.

[0013] Furthermore, in the case of the conventional battery module 1, only the lower edge portions of the battery cells 2 are in contact with the thermally conductive resin layer 5. Heat generated in the battery cells 2 is dissipated at the lower edge portions of the battery cells 2 by passing through the thermally conductive resin layer 5 and the heat sink 6 in that order. In other words, the conventional battery module 1 is a type of edge cooling method that dissipates heat through the lower edge portions of the battery cells 2. This edge cooling method has a simplified structure, but suffers from the problem of poor cooling efficiency, as heat generated in the battery cells 2 is dissipated only through the narrow lower edge portions.

[0014] In summary, there is a need for a more effective method for improving the cooling efficiency of a battery cell cluster. Summary of the Invention [Problem to be solved by the invention]

[0015] An object of the present invention is to provide a battery assembly and a device including the same that have improved cooling efficiency and improved cooling performance.

[0016] However, the problems to be solved by the embodiments of the present invention are not limited to the above problems, and can be variously expanded within the scope of the technical ideas included in the present invention. [Means for solving the problem]

[0017] A battery assembly according to one embodiment of the present invention includes a battery cell stack in which a plurality of battery cells are stacked, a frame that houses the battery cell stack and includes a first side portion, a second side portion, a ceiling portion, and a bottom portion, and an inlet and an outlet for circulating a coolant within the frame. The coolant flows into the frame through the inlet and is discharged through the outlet. A pad member is disposed at at least one location between the plurality of battery cells, and at least one of the pad members extends from the ceiling portion to the bottom portion of the frame.

[0018] Separate flow paths for the coolant may be formed between the pad members.

[0019] At least one upper end of the pad member can be in close contact with the ceiling portion, and at least one lower end of the pad member can be in close contact with the bottom portion.

[0020] The pad member may be in the form of a single pad extending from the ceiling to the bottom of the frame.

[0021] The pad member may include a main pad facing one side of the battery cell, a first vane fitted between the main pad and the ceiling portion of the frame, and a second vane fitted between the main pad and the bottom portion of the frame.

[0022] The inlet and the outlet may be located on opposite sides of the battery cell stack.

[0023] The battery assembly may further include a first end plate and a second end plate covering the open sides of the frame, respectively.

[0024] The inlet may be provided in the first end plate and the outlet may be provided in the second end plate.

[0025] The inlet may be located below a center of the height of the battery cell stack, and the outlet may be located above the center of the height of the battery cell stack.

[0026] In a first direction and a second direction that are parallel to the direction in which the plurality of battery cells are stacked and opposite to each other, the inlet may be positioned offset in the first direction from a center of the battery cell stack in the direction in which the plurality of battery cells are stacked, and the outlet may be positioned offset in the second direction from a center of the battery cell stack in the direction in which the plurality of battery cells are stacked.

[0027] In the battery cell stack, the plurality of battery cells can be stacked along a direction from the first side surface portion of the frame to the second side surface portion of the frame.

[0028] The plurality of battery cells may be stacked with one surface of each battery cell parallel to the first side surface portion and the second side surface portion.

[0029] The refrigerant may be insulating oil.

[0030] The coolant can be in direct contact with and cool the battery cell stack housed inside the frame.

[0031] A plurality of the pad members may be provided, and the plurality of pad members may be arranged at predetermined intervals along the stacking direction of the plurality of battery cells.

[0032] The pad member may further be disposed between the battery cell stack and the first side surface portion.

[0033] The pad member may further be disposed between the battery cell stack and the second side surface portion.

[0034] The battery assembly may further include cooling fins positioned between the plurality of battery cells, the cooling fins extending to the top or bottom and contacting the top or bottom.

[0035] A device according to one embodiment of the present invention includes the battery assembly. [Effects of the Invention]

[0036] According to an embodiment of the present invention, a refrigerant can be directly injected into the battery assembly to directly cool the battery cells. This direct cooling of the battery cells with the refrigerant can improve the cooling efficiency of the battery assembly and a device including the battery assembly.

[0037] In addition, the pad members disposed between the battery cells in the battery assembly allow the coolant to flow uniformly, thereby reducing areas where the coolant flow is stagnant in the battery assembly and ultimately enabling uniform and excellent cooling of each battery cell.

[0038] The effects of the present invention are not limited to those mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the claims. [Brief explanation of the drawings]

[0039] [Figure 1]1 is a cross-sectional view showing a cross section of a battery pack including a conventional battery module. [Figure 2] 1 is a perspective view showing a battery assembly according to an embodiment of the present invention; [Figure 3] FIG. 3 is an exploded perspective view of the battery assembly of FIG. 2. [Figure 4] 4 is a perspective view showing a frame included in the battery assembly of FIG. 3. FIG. [Figure 5] 4 is a perspective view showing a battery cell stack, a first bus bar assembly, and a second bus bar assembly included in the battery assembly of FIG. 3. FIG. [Figure 6] FIG. 6 is an exploded perspective view of the battery cell stack, the first bus bar assembly, and the second bus bar assembly of FIG. 5. [Figure 7] FIG. 7 is a plan view showing one of the battery cells included in the battery cell stacks of FIGS. 5 and 6. [Figure 8] 1 is a plan view showing a battery assembly according to an embodiment of the present invention in which a ceiling portion of a frame is omitted, as viewed from above. [Figure 9] FIG. 2 is a front view of a battery assembly according to an embodiment of the present invention, with a first end plate and a first bus bar frame removed; [Figure 10] FIG. 10 is an enlarged partial view of part "A" in FIG. 9. [Figure 11] 1 is a perspective view showing a first sealing assembly according to an embodiment of the present invention attached to one side of a frame. [Figure 12] 12(a), (b) and (c) are diagrams showing the process of assembling the first sealing assembly of FIG. 11. [Figure 13] 12(a), (b) and (c) are diagrams showing the process of mounting the first sealing assembly of FIG. 11 on one side of the frame. [Figure 14] 1 is an exploded perspective view showing a first end plate mounted to a first sealing assembly according to an embodiment of the present invention; FIG. [Figure 15]15 is a diagram showing the configuration in FIG. 14 excluding the first end plate, viewed in the −x-axis direction on the yz plane. [Figure 16] 16 is a partial cross-sectional view showing an enlarged view of a portion corresponding to "C" in the cross section taken along the cutting line BB' in FIG. 15. FIG. [Figure 17] 10 is a view showing a second sealing assembly according to an embodiment of the present invention mounted on another side of the frame. FIG. [Figure 18] 10 is an exploded perspective view showing a second end plate being attached to a second sealing assembly according to an embodiment of the present invention; FIG. [Figure 19] 19 is a diagram of the configuration in FIG. 18 excluding the second end plate, viewed in the x-axis direction on the yz plane. [Figure 20] 20 is a partial cross-sectional view showing an enlarged view of a portion corresponding to "E" in the cross section taken along the cutting line DD' in FIG. 19. FIG. [Figure 21] FIG. 10 is an exploded perspective view of a battery cell stack, a first bus bar assembly, and a second bus bar assembly according to a modified embodiment of the present invention. [Figure 22] FIG. 10 is a front view of a battery assembly according to a modified embodiment of the present invention, with a first end plate and a first bus bar frame removed. [Figure 23] FIG. 23 is an enlarged partial view of part "F" in FIG. 22. DETAILED DESCRIPTION OF THE INVENTION

[0040] The present invention may be embodied in various different forms and is not limited to the embodiments set forth herein.

[0041] In order to clearly explain the present invention, parts that are not necessary for the explanation will be omitted, and the same reference numerals will be used throughout the specification to refer to the same or similar components.

[0042] In addition, the size and thickness of each component shown in the drawings are arbitrarily shown for the convenience of explanation, and the present invention is not necessarily limited to the drawings. In the drawings, thicknesses are exaggerated to clearly show various layers and regions. In the drawings, thicknesses of some layers and regions are exaggerated for the convenience of explanation.

[0043] Furthermore, when a layer, film, region, plate, or other part is described as being "above" 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 between them. Conversely, when a part is described as being "directly above" another part, it means that there is no other part between them. Note that being "above" a reference part means being located above or below the reference part, and does not necessarily mean being located "above" in the opposite direction of gravity.

[0044] Also, throughout the specification, when a part is said to "comprise" a certain element, this does not mean that it excludes other elements, but that it can further include other elements, unless otherwise specified to the contrary.

[0045] Furthermore, throughout the specification, "in a plane" means the part being viewed from above, and "in cross section" means the part being viewed from the side across a vertical cross section.

[0046] Fig. 2 is a perspective view showing a battery assembly according to an embodiment of the present invention. Fig. 3 is an exploded perspective view of the battery assembly of Fig. 2. Fig. 4 is a perspective view showing a frame included in the battery assembly of Fig. 3. Fig. 5 is a perspective view showing a battery cell stack, a first bus bar assembly, and a second bus bar assembly included in the battery assembly of Fig. 3. Fig. 6 is an exploded perspective view of the battery cell stack, the first bus bar assembly, and the second bus bar assembly of Fig. 5. Fig. 7 is a plan view showing one of the battery cells included in the battery cell stacks of Figs. 5 and 6.

[0047] 2 to 7, a battery assembly 100 according to an embodiment of the present invention includes a battery cell stack 120 in which a plurality of battery cells 110 are stacked, a frame 200 in which the battery cell stack 120 is housed and which includes a first side portion 210, a second side portion 220, a ceiling portion 230, and a bottom portion 240, and an inlet 421 and an outlet 461 for circulating a refrigerant within the frame 200. The refrigerant flows into the frame 200 through the inlet 421 and is discharged through the outlet 461. Details of the refrigerant, the inlet 421, and the outlet 461 will be described later.

[0048] The battery cell 110 according to this embodiment may be a battery cell of various shapes, such as a pouch-type battery cell, a prismatic battery cell, or a cylindrical battery cell. As an example, as shown in Fig. 7, the battery cell 110 according to this embodiment may be a pouch-type battery cell. While the following description will be given with reference to a pouch-type battery cell, the battery cell 110 according to this embodiment is not limited thereto, and various types of battery cells may be used.

[0049] The battery cell 110 according to this embodiment may have a configuration in which an electrode assembly having electrode leads 130 protruding in one or both directions is housed in a pouch case 114. Such a battery cell 110 may have a rectangular sheet shape. The battery cell 110 may be formed by housing an electrode assembly in a pouch case 114 made of a laminate sheet including a resin layer and a metal layer, and then bonding the outer periphery of the pouch case 114. As an example, the battery cell 110 may have a structure in which two electrode leads 130 face each other and protrude from one end 114a and the other end 114b of the cell body 113, respectively. As another example, the electrode leads 130 of the battery cell 110 may all protrude in one direction. One of the electrode leads 130 is a positive electrode lead, and the other is a negative electrode lead.

[0050] The battery cell 110 can be manufactured by bonding both ends 114a, 114b of the pouch case 114 to one side 114c connecting them while an electrode assembly (not shown) is housed in the pouch case 114. In other words, the battery cell 110 according to this embodiment of the present invention may have a total of three sealing portions, which are sealed by a method such as fusion, and the remaining side may be formed as a folding portion 115. In other words, the battery cell 110 according to this embodiment may be a pouch-type secondary battery in which an electrode assembly is housed inside the pouch case 114 and the outer periphery of the pouch case 114 is sealed to form a sealing portion. FIG. 7 only shows that sealing portions are formed at both ends 114a and 114b of the pouch case 114, and does not show a sealing portion on the side opposite the folding portion 115, but the sealing portion on the side opposite the folding portion 115 is folded to one side after sealing is completed to utilize space.

[0051] The laminate sheet pouch case 114 may include an inner resin layer for sealing, a metal layer for preventing penetration of substances, and an outermost resin layer. Based on the electrode assembly inside the pouch case 114, the inner resin layer may be located innermost, the outer resin layer may be located outermost, and the metal layer may be located between the inner and outer resin layers.

[0052] The outer resin layer has excellent tensile strength and weather resistance relative to its thickness and exhibits electrical insulation to protect the electrode assembly from the outside. This outer resin layer may include polyethylene terephthalate (PET) resin or nylon resin. The metal layer may prevent air, moisture, etc. from entering the pouch-type secondary battery. This metal layer may include aluminum (Al). The inner resin layers may be heat-sealed to each other by applying heat and / or pressure with the electrode assembly inside. This inner resin layer may include cast polypropylene (CPP) or polypropylene (PP).

[0053] The pouch case 114 may be divided into two sections, and a recessed storage section in which an electrode assembly can be placed may be formed in at least one of the two sections. A sealing section may be formed around the outer periphery of the storage section by joining the inner resin layers of the two sections of the pouch case 114 together. By sealing the pouch case in this manner, a battery cell 110, which is a pouch-type secondary battery, can be manufactured.

[0054] The battery cell stack 120 may include a plurality of battery cells 110. The plurality of battery cells 110 may be stacked so as to be electrically connectable to each other. For example, the plurality of battery cells 110 may be stacked upright in a direction parallel to the Y-axis. Specifically, in the battery cell stack 120, the battery cells 110 may be stacked in a direction from the first side surface 210 to the second side surface 220 of the frame 200. The battery cells 110 may be stacked with one surface of each battery cell 110 parallel to the first side surface 210 and the second side surface 220. Here, the one surface of each battery cell 110 may be one surface of the cell body 113 (see FIG. 7 ) of each battery cell 110. The electrode leads 130 may protrude in a direction perpendicular to the stacking direction of the battery cells 110. In each battery cell 110, one electrode lead 130 may protrude toward the X-axis direction, and the other electrode lead 130 may protrude toward the −X-axis direction. In the case of a battery cell in which the electrode lead 130 protrudes in only one direction, the electrode lead 130 can protrude in the X-axis direction or the −X-axis direction.

[0055] The frame 200 may protect the battery cell stack 120 and the electrical components connected thereto from external physical impact. The frame 200 is a member for forming a space in which the battery cells 110 are housed and may cover at least a portion of the battery cell stack 120. As described above, the frame 200 includes a first side portion 210, a second side portion 220, a ceiling portion 230, and a bottom portion 240. The battery cell stack 120 and the electrical components connected thereto may be housed in the internal space of the frame 200, i.e., the internal space formed by the first side portion 210, the second side portion 220, the ceiling portion 230, and the bottom portion 240. There are no particular limitations on the material of the frame 200, but as an example, the frame 200 may include a metal material.

[0056] The structure of the frame 200 may vary. According to one embodiment of the present invention, the frame 200 may have a mono-frame structure. Here, the mono-frame may be in the form of a metal plate material in which the top, bottom, and both side surfaces are integrated. The mono-frame may be manufactured by extrusion molding. In this example, the first side surface portion 210, the second side surface portion 220, the ceiling portion 230, and the bottom portion 240 may be in an integrated form.

[0057] However, the structure of the frame 200 is not limited thereto, and in another embodiment, the frame 200 may have a structure in which components are coupled to one another. For example, at least one of the first side surface portion 210, the second side surface portion 220, the ceiling portion 230, and the bottom portion 240 may be separate components that are separated from one another, and these separate components may be coupled to one another by a mechanical fastening method, welding, etc. In this example, the frame 200 may be formed by coupling at least one of the first side surface portion 210, the second side surface portion 220, the ceiling portion 230, and the bottom portion 240 by a mechanical fastening method, welding, etc.

[0058] For example, the frame 200 may include a U-shaped frame and an upper plate coupled to each other. In this case, the U-shaped frame may have a lower surface and two side surfaces extending upward from both corners of the lower surface, and the upper plate may be plate-shaped. Here, the U-shaped frame may be a component corresponding to the first side surface 210, the second side surface 220, and the bottom surface 240, and the upper plate may be a component corresponding to the ceiling surface 230. In this case, each frame or plate constituting the U-shaped frame may be manufactured by press molding. Furthermore, the frame 200 may be provided as a mono-frame, a U-shaped frame, or an L-shaped frame, or may be provided in various structures not described in the above examples.

[0059] In summary, the frame 200 of the present invention can be provided in various structures without any special restrictions on its shape, material, manufacturing method, and connection form between components, as long as it can form a space to accommodate the battery cells 110.

[0060] The frame 200 may have open sides. More specifically, the frame 200 may be provided in a form that is open along the longitudinal direction of the battery cells 110. Here, the longitudinal direction of the battery cells 110 is a direction perpendicular to the direction in which the battery cells 110 are stacked, and may correspond to the direction in which the electrode leads 130 protrude from the battery cells 110. The open sides of the frame 200 may be covered by first and second bus bar assemblies 300a and 300b, a sealing assembly 400, or an end plate 500, which will be described later. The battery cell stack 120 can be protected from external physical impacts by being housed in the internal space of the frame 200.

[0061] Meanwhile, the battery assembly 100 may include a first busbar assembly 300a and a second busbar assembly 300b located on one side and the other side of the battery cell stack 120. Specifically, the first busbar assembly 300a and the second busbar assembly 300b may be located in a direction in which the electrode leads 130 of the battery cells 110 included in the battery cell stack 120 protrude. The first busbar assembly 300a and the second busbar assembly 300b may each include a busbar frame, a busbar, and a terminal busbar, which will be described later.

[0062] Meanwhile, the battery assembly 100 may include a sealing assembly 400. The sealing assembly 400 may be formed to be located on both open sides of the frame 200 and cover the battery cell stack 120. The sealing assembly 400 located on one open side of the frame 200 may be a first sealing assembly 410, and the sealing assembly 400 located on the other open side of the frame 200 may be a second sealing assembly 450. That is, the battery assembly 100 according to this embodiment may further include a first sealing assembly 410 and a second sealing assembly 450, which respectively cover both open sides of the frame 200.

[0063] The sealing assembly 400 can separate the open sides of the frame 200 from the external environment. Specifically, when a refrigerant is injected into the frame 200 (described later), the sealing assembly 400 can seal the refrigerant to prevent it from leaking to the outside.

[0064] The battery assembly 100 according to this embodiment may include end plates 500 located on both open sides of the frame 200. Specifically, the end plates 500 may be located on both open sides of the frame 200 and configured to cover the sealing assembly 400. The battery assembly 100 may include a first end plate 510 and a second end plate 550 covering one open side and the other open side of the frame 200, respectively. That is, the end plate 500 located on one open side of the frame 200 may be the first end plate 510, and the end plate 500 located on the other open side of the frame 200 may be the second end plate 550. The first end plate 510 may cover the first sealing assembly 410 from the outside, and the second end plate 550 may cover the second sealing assembly 450 from the outside. In other words, the first sealing assembly 410 can be positioned between the battery cell stack 120 and the first end plate 510, and the second sealing assembly 450 can be positioned between the battery cell stack 120 and the second end plate 550. There are no particular limitations on the material of the end plate 500, but as an example, the end plate 500 can include a metal material and be joined to the frame 200 by welding. The end plate 500 can physically protect the battery cell stack 120 and other electrical components from external impacts.

[0065] Hereinafter, the structures of the pad member 700a and the cooling fins 800 according to an embodiment of the present invention will be described in detail.

[0066] Fig. 8 is a plan view of a battery assembly according to an embodiment of the present invention, in which the ceiling of the frame is omitted, as viewed from above. Fig. 9 is a front view of a battery assembly according to an embodiment of the present invention, in which the first end plate and the first bus bar frame are removed, as viewed from the front. Fig. 10 is a partial view showing an enlarged view of part "A" in Fig. 9.

[0067] 3, 6, 8, 9, and 10, in the battery assembly 100 according to this embodiment, a pad member 700a is disposed at at least one location between the battery cells 110. A plurality of pad members 700a may be provided, and the plurality of pad members 700a may be disposed at predetermined intervals along the stacking direction of the battery cells 110. A separate pad member 700a may be further disposed between the battery cell stack 120 and the first side surface portion 210. A separate pad member 700a may be further disposed between the battery cell stack 120 and the second side surface portion 220.

[0068] The pad member 700a according to this embodiment may be a plate-shaped member made of foam. The pad member 700a can absorb swelling of the battery cells 110 caused by charging and discharging. Specifically, the battery cells 110 may generate gas internally due to degradation as they are repeatedly charged and discharged. When gas is generated internally, the internal pressure increases, causing swelling, in which at least a portion of the exterior material expands. In particular, in the case of a pouch-type secondary battery, the structural rigidity of the exterior material is weaker than in a can-type secondary battery, and the swelling phenomenon may occur more severely. If the swelling of the battery cells 110 cannot be absorbed and controlled, structural deformation may occur in the battery assembly 100, which has a stacked structure of multiple battery cells 110, and the durability and performance of the battery assembly 100 may be adversely affected. The pad member 700a according to this embodiment is compressed in correspondence with the battery cell 110 in which swelling has occurred, and can absorb the swelling of the battery cell 110, ultimately minimizing structural deformation of the battery assembly 100. There are no particular limitations on the material of the pad member 700a as long as it can absorb the swelling of the battery cell 110 when compressed, and one example of the material may include polyurethane.

[0069] Meanwhile, the battery assembly 100 according to this embodiment may further include cooling fins 800 positioned between the battery cells 110. The cooling fins 800 may be positioned between two battery cells 110. For example, as shown in Fig. 9, one cooling fin 800 adjacent to another cooling fin 800 may be positioned with the two battery cells 110 sandwiched between them.

[0070] The cooling fin 800 according to this embodiment may extend to the ceiling portion 230 or the bottom portion 240 of the frame 200 and come into contact with the ceiling portion 230 or the bottom portion 240. Specifically, the cooling fin 800 may include a body portion 810 that comes into contact with one surface of the battery cell 110. Here, the one surface of the battery cell 110 may be one surface of the cell body 113 (see FIG. 7 ) of the battery cell 110, and may be one surface of the battery cell 110 extending along the longitudinal direction (x-axis direction).

[0071] One surface of the body 810 may contact one surface of the battery cell 110 opposite the one surface of the body 810. The other surface of the body 810 may contact one surface of another adjacent battery cell 110 opposite the other surface of the body 810. In this case, although not specifically shown, an adhesive member may be interposed between the one surface of the battery cell 110 and the body 810, thereby adhesively fixing the battery cell 110 to the body 810. For example, the adhesive member may be an insulating tape.

[0072] If the size of the body 810 is larger than the size of the battery cell 110, the upper and lower portions of the battery cell 110 may be positioned at a certain distance from the ceiling 230 and bottom 240 of the frame 200. Specifically, if the height of the body 810 is greater than the height of the battery cell 110, the battery cell 110 may be positioned at the center of the body 810 and adhesively fixed thereto. In this case, the upper and lower portions of the battery cell 110 may be positioned at a certain distance from the ceiling 230 and bottom 240 of the frame 200. Here, the height of the battery cell 110 and the body 810 may correspond to the length in the z-axis direction.

[0073] The cooling fin 800 may further include an extension 820 extending from one end of the main body 810. As an example, the cooling fin 800 may be L-shaped. Specifically, the cooling fin 800 may include the main body 810 facing one side of the battery cell 110, and the extension 820 extending from one end of the main body 810 along the direction in which the battery cells 110 are stacked (a direction parallel to the Y-axis). One side of the extension 820 may be parallel to the direction in which the battery cells 110 are stacked. Furthermore, one side of the extension 820 may be perpendicular to one side of the main body 810.

[0074] The extension 820 may contact the ceiling 230 or the bottom 240 of the frame 200. Specifically, one surface of the extension 820 may face the upper surface or the lower surface of the battery cell 110, and the other surface of the extension 820 may contact the ceiling 230 or the bottom 240 of the frame 200.

[0075] For example, in any one of the cooling fins 800, one surface of the extension portion 820 may face the lower surface of the battery cell 110, and the other surface of the extension portion 820 may contact the bottom 240 of the frame 200. As a result, the cooling fin 800 may be fixed and positioned within the frame 200. In addition, in another of the cooling fins 800, one surface of the extension portion 820 may face the upper surface of the battery cell 110, and the other surface of the extension portion 820 may contact the ceiling 230 of the frame 200. Meanwhile, the upper and lower surfaces of the battery cell 110 may be adhesively fixed to the main body 810 and positioned at a certain height from the ceiling 230 and bottom 240 of the frame 200.

[0076] However, the shape of the cooling fin 800 is not limited to that shown in the drawing, and it may be a flat plate shape or any other shape that can contact the battery cell 110 and fix the battery cell 110.

[0077] The cooling fin 800 according to this embodiment may include a metal material. Specifically, the cooling fin 800 may include a metal material with high thermal conductivity. Therefore, the cooling fin 800 can directly receive heat generated in the battery cell 110 during charging and discharging. When heat is generated, the heat is transferred to the cooling fin 800 in contact with one side of the battery cell 110, thereby providing primary cooling. A refrigerant (described later) can then directly contact the upper and lower parts of the battery cell 110, thereby providing secondary cooling. This allows direct cooling of the upper and lower parts of the battery cell, which have traditionally been relatively difficult to cool, thereby improving cooling efficiency.

[0078] Hereinafter, a structure for circulating a refrigerant inside the battery assembly 100 according to this embodiment will be described in detail.

[0079] 2, 3, 6, 8, 9, and 10 again, as described above, the refrigerant flows into the frame 200 through the inlet 421 and then is discharged to the outside of the battery assembly 100 through the outlet 461. In this embodiment, the refrigerant can cool the battery cell stack 120 housed inside the frame 200 by directly contacting the battery cell stack 120. More specifically, the refrigerant can receive heat generated therefrom by directly contacting the battery cell stack 120 housed inside the frame 200, the first and second bus bar assemblies 300a and 300b (described later), and other electrical components. In other words, the battery assembly 100 according to this embodiment may have a direct cooling structure in which the refrigerant directly flows into and circulates inside the frame 200 to cool the battery cells 110 and electrical components. Therefore, while the conventional battery module 1 (see FIG. 1) indirectly cools the battery module 1 using a heat sink 6 or the like, the battery assembly 100 according to this embodiment can improve the cooling efficiency by direct cooling, thereby extending the battery life.

[0080] The coolant may be a fluid. However, since the coolant directly contacts the battery cell stack 120, the first and second bus bar assemblies 300a, 300b, and other electrical components within the battery assembly 100, the coolant must be electrically insulated. Therefore, the coolant may be a material having insulating properties. For example, the coolant may be insulating oil.

[0081] Meanwhile, in the battery assembly 100 according to this embodiment, the inlet 421 and the outlet 461 may be located on opposite sides of the battery cell stack 120. In other words, the battery cell stack 120 may be located between the inlet 421 and the outlet 461. The inlet 421 may be provided in the first end plate 510, and the outlet 461 may be provided in the second end plate 550. The inlet 421 being provided in the first end plate 510 includes both the inlet 421 being integrally formed with the first end plate 510 and the inlet 421 passing through an inlet opening 540 formed in the first end plate 510 and being exposed to the outside of the first end plate 510. Similarly, the provision of the outlet 461 on the second end plate 550 includes both the outlet 461 being integrally formed on the second end plate 550 and the outlet 461 passing through an outlet opening 560 formed on the second end plate 550 and being exposed to the outside of the second end plate 550.

[0082] In the battery assembly 100 according to this embodiment, the coolant CL flows along the longitudinal direction of the battery cells 110 (parallel to the X-axis) to directly cool the battery cell stack 120, the first and second busbar assemblies 300a, 300b, and other electrical components. As described above, in the battery cell stack 120, the battery cells 110 can be stacked in the direction from the first side surface 210 to the second side surface 220 of the frame 200, with one side of each battery cell 110 parallel to the first side surface 210 and the second side surface 220. In this stacking configuration of the battery cell stack 120, the coolant CL is designed to flow along the longitudinal direction of the battery cells 110, so that the coolant CL can cool each battery cell 110 evenly without being concentrated in some battery cells 110. If the coolant were designed to flow along the stacking direction of the battery cells 110, the flow of the coolant would be uneven, and only some battery cells 110 would be cooled, resulting in unbalanced cooling.

[0083] Meanwhile, at least one of the pad members 700a according to this embodiment extends from the ceiling 230 to the bottom 240 of the frame 200. Separate coolant flow paths FP may be formed between the pad members 700a. In the direct cooling structure of this embodiment, the battery cells 110 are directly cooled by the coolant, resulting in high cooling performance. However, areas where the coolant flow stagnates may occur within the frame 200, resulting in cooling imbalances. In particular, areas where the coolant flow stagnates may occur between the second end plate 550, where the outlet 461 is located, and the battery cell stack 120. The area between the second end plate 550 and the battery cell stack 120 is where the electrode leads 130 of the battery cells 110 and the second bus bar 330b (described later) are located. These areas generate a large amount of heat during charging and discharging of the battery cells 110. Therefore, stagnation of the coolant flow in this region may exacerbate cooling imbalances within the battery assembly 100, which may cause performance degradation and deterioration of the battery cells 110.

[0084] In order to solve this problem of refrigerant flow stagnation, in this embodiment, a pad member 700a is provided that extends from the ceiling portion 230 to the bottom portion 240 of the frame 200, and a refrigerant flow path FP is realized through the pad member 700a.

[0085] In the past, the coolant flowed randomly through the wide space inside the frame 200 from the inlet 421 to the outlet 461, resulting in areas where the coolant flow stagnated. In contrast, in this embodiment, when the pad members 700a are extended and a coolant flow path FP is formed between the pad members 700a, the coolant flows smoothly along the flow path FP from the inlet 421 to the outlet 461, and no stagnation of the coolant flow occurs. In FIG. 8, when the coolant CL flows inside the frame 200 from the inlet 421 to the outlet 461, the coolant CL flows smoothly through the spaces between the pad members 700a as indicated by the arrows. As a result, in the battery assembly 100 according to this embodiment, stagnation of the coolant flow and the resulting cooling imbalance are minimized, thereby preventing performance degradation and deterioration of the battery cells 110. In other words, in this embodiment, the pad member 700a not only functions to absorb swelling of the battery cell 110, but also functions to form a flow path FP for the refrigerant, thereby eliminating stagnation of the refrigerant flow and resulting cooling imbalance.

[0086] 10 shows that coolant flow paths FP are formed between the pad members 700a in the region between the battery cells 110 and the bottom portion 240 of the frame 200. Although not specifically enlarged, coolant flow paths FP may also be formed between the pad members 700a in the region between the battery cells 110 and the ceiling portion 230 of the frame 200. On the other hand, if no pad members 700a are arranged on the outermost sides of the battery cell stack 120, coolant flow paths may be formed between one of the pad members 700a and the first side surface portion 210, and between another of the pad members 700a and the second side surface portion 220.

[0087] At least one upper end of the pad member 700a may be in close contact with the ceiling 230 of the frame 200, and at least one lower end of the pad member 700a may be in close contact with the bottom 240 of the frame 200. Furthermore, the upper and lower ends of some of the pad members 700a may be in close contact with the extensions 820 of the cooling fins 800, as shown in FIGS. 9 and 10 . The upper and lower ends of some of the pad members 700a may be in close contact with one side of the extensions 820, and the other side of the extensions 820 may be in close contact with the ceiling 230 or bottom 240 of the frame 200. In other words, to ensure that a refrigerant flow path FP is clearly formed between the pad members 700a, it is preferable that there is no additional space between the upper end of the pad member 700a and the ceiling 230 of the frame 200, and that there is no additional space between the lower end of the pad member 700a and the bottom 240 of the frame 200.

[0088] Meanwhile, the pad member 700a according to an embodiment of the present invention may be a single pad extending from the ceiling portion 230 of the frame 200 to the bottom portion 240 of the frame 200. In other words, the pad member 700a according to this embodiment may be a single pad rather than being divided into several members.

[0089] The inlet 421 may be located below the center of the height of the battery cell stack 120. The outlet 461 may be located above the center of the height of the battery cell stack 120. Here, the height of the battery cell stack 120 refers to the length in the z-axis direction in the drawing. The positions of the inlet 421 and the outlet 461 are not limited thereto, but when the positions of the inlet 421 and the outlet 461 are set as above, the inside of the frame 200 can be sufficiently filled with the refrigerant.

[0090] If the inlet 421 is located above the center of the battery cell stack 120, the refrigerant may flow into the battery assembly 100 from a high position, causing bubbles to form inside the refrigerant. These bubbles may impede the cooling effect.

[0091] Furthermore, if the outlet 461 is located below the center of the battery cell stack 120 based on its height, the refrigerant that flows into the battery assembly 100 will only fill it up to the height of the outlet 461 before escaping to the outside, which may result in the battery assembly 100 not being filled with a sufficient amount of refrigerant, resulting in reduced cooling performance.

[0092] Therefore, in order to prevent bubbles from forming in the inflowing refrigerant and to gradually fill the interior of the battery assembly 100 with the refrigerant to cool the entire interior, it is preferable that the inlet 421 be located below the center of the height of the battery cell stack 120 and the outlet 461 be located above the center of the height of the battery cell stack 120.

[0093] 8 and 9, in a first direction d1 and a second direction d2 that are parallel to and opposite the direction in which the battery cells 110 are stacked, the inlet 421 may be positioned offset in the first direction d1 from the center of the battery cell stack 120 in the direction in which the battery cells 110 are stacked, and the outlet 461 may be positioned offset in the second direction d2 from the center of the battery cell stack 120 in the direction in which the battery cells are stacked. In other words, it is preferable that the inlet 421 and the outlet 461 are positioned on opposite sides of each other based on the direction in which the battery cells 110 are stacked. Only when the inlet 421 and the outlet 461 are arranged in this manner can the refrigerant flow throughout the entire space inside the frame 200 and evenly cool all of the battery cells 110. If the inlet 421 and the outlet 461 were both located at the center of the battery cell stack 120 in the stacking direction of the battery cells 110, the refrigerant would flow only to the center, which has the least flow resistance, and would not flow well to the battery cells 110 located at the outer portions of the battery cell stack 120. This ultimately results in unbalanced cooling within the battery assembly 100. Furthermore, if the inlet 421 and the outlet 461 were both located offset in either the first direction d1 or the second direction d2, the refrigerant would only flow to some of the outer battery cells 110 adjacent to the offset direction, similarly resulting in unbalanced cooling within the battery assembly 100. Therefore, in order to induce an even flow of refrigerant to all of the battery cells 110 within the battery assembly 100, it is preferable that the inlet 421 and the outlet 461 be located on opposite sides of each other in the stacking direction of the battery cells 110, as described above.

[0094] Referring again to Figures 3, 5 and 6, as described above, the battery assembly 100 may include a first bus bar assembly 300a and a second bus bar assembly 300b located on one side and the other side of the battery cell stack 120, respectively.

[0095] The first bus bar assembly 300a may include a first bus bar frame 310a and a first bus bar 330a attached to the first bus bar frame 310a.

[0096] The first bus bar frame 310a may be located on one side of the battery cell stack 120 to cover one side of the battery cell stack 120 and also to guide the connection between the battery cell stack 120 and an external device.

[0097] The first bus bar 330a may be attached to the first bus bar frame 310a. For example, the inner surface of the first bus bar frame 310a may face the battery cell stack 120, and the first bus bar 330a may be attached to the outer surface of the first bus bar frame 310a.

[0098] The first bus bar frame 310a may include an electrically insulating material. The first bus bar frame 310a may prevent an electrical short circuit by restricting contact of the first bus bar 330a with other parts of the battery cell 110 other than the part connected to the electrode lead (not shown).

[0099] The first bus bar 330a is attached to the outer surface of the first bus bar frame 310a and may serve to electrically connect the battery cells 110 included in the battery cell stack 120 and electrically connect the battery cell stack 120 to an external device circuit. The first bus bar 330a is located on the first bus bar frame 310a, and the first bus bar assembly 300a is covered by the sealing assembly 400 and end plate 500 (described below), so it can be protected from external impacts and the like, and deterioration of durability due to external moisture, etc. can be minimized.

[0100] The first bus bar 330a may be electrically connected to the battery cell stack 120 via the electrode leads 130 of the battery cells 110. Specifically, the electrode leads 130 of the battery cells 110 may pass through slits formed in the first bus bar frame 310a, bend, and be connected to the first bus bar 330a. The first bus bar 330a may electrically connect the battery cells 110 included in the battery cell stack 120 in series or parallel. There are no particular limitations on the connection method between the electrode leads 130 and the first bus bar 330a, and welding may be used, for example.

[0101] The second bus bar assembly 300b covers the other side of the battery cell stack 120 and can electrically connect the battery cells 110 of the battery cell stack 120. The detailed configuration of the second bus bar assembly 300b will be described again with reference to FIG. 17.

[0102] Meanwhile, a flexible printed circuit board (FPCB) 350 may be provided to electrically connect the first bus bar assembly 300a and the second bus bar assembly 300b. The flexible printed circuit board 350 is attached to extend in the longitudinal direction of the battery cells 110 and is configured to sense the battery cells 110. That is, as shown in FIG. 6, the flexible printed circuit board 350 is positioned on the upper surface of the battery cell stack 120 and senses voltage data and thermal data of the battery cells 110. In particular, the flexible printed circuit board 350 can be bent from one end toward the first bus bar frame 310a and electrically connected to the first bus bar 330a. This allows voltage data of each battery cell 110 to be sensed and transmitted to the outside.

[0103] FIG. 11 is a perspective view showing a first sealing assembly according to an embodiment of the present invention mounted on one side of a frame.

[0104] 2, 3, 6, 7, and 11, as described above, the battery assembly 100 may include a first sealing assembly 410 and a second sealing assembly 450, which respectively cover both open sides of the frame 200. The inlet 421 may be formed in the first sealing assembly 410, and the outlet 461 may be formed in the second sealing assembly 450. However, this is just one exemplary structure, and in other embodiments of the present invention, the inlet and the outlet may be formed in the first end plate 510 and the second end plate 550, respectively.

[0105] As described above, if the direction parallel to the direction in which the electrode leads 130 protrude from the battery cell 110 is the longitudinal direction of the battery cell 110, the direction parallel to the X-axis may correspond to the longitudinal direction of the battery cell 110. The first sealing assembly 410, the first busbar assembly 300a, the battery cell stack 120, the second busbar assembly 300b, and the second sealing assembly 450 may be sequentially positioned along this longitudinal direction. That is, the coolant that flows in through the inlet 421 formed in the first sealing assembly 410 can pass through the first busbar assembly 300a, the battery cell stack 120, and the second busbar assembly 300b and be discharged through the outlet 461 formed in the second sealing assembly 450.

[0106] The first sealing assembly 410 may be attached to cover the first bus bar assembly 300a. The first sealing assembly 410 may include a first sealing cover 420 which is a plate covering an open side of the frame 200, an inlet 421 which is a hole formed in the first sealing cover 420, and a module connector 430 which is attached to a region of the first sealing cover 420.

[0107] The first sealing cover 420 is a plate that covers an open side of the frame 200, and may have a size corresponding to the size of the open side of the frame 200. That is, the first sealing cover 420 may be attached to the frame 200 while covering the open side of the frame 200. For example, the first sealing cover 420 may be mated with the frame 200.

[0108] The inlet 421 may be a hole formed in one region of the first sealing cover 420. The inlet 421 may be a hole that protrudes toward the outer surface (X-axis direction) of the first sealing cover 420. That is, the inlet 421 may be a hole that protrudes in a direction opposite to the direction in which the frame 200 is positioned relative to the first sealing cover 420. The protruding inlet 421 may pass through an inlet opening 540 formed in a first end plate 510, which will be described later.

[0109] The inlet 421 may be located below the center of the height of the battery cell stack 120. The inlet 421 may be located near the lower end of the first sealing assembly 410. Specifically, the inlet 421 may be located below the center of the height of the first sealing assembly 410.

[0110] The module connector 430 may detect and control phenomena such as overvoltage, overcurrent, and overheating of the battery cells. The module connector 430 is for LV (Low voltage) connection, and can transmit voltage information and temperature information of the battery cells to an external BMS (Battery Management System) via the module connector 430.

[0111] The module connector 430 can be attached to the first sealing cover 420. At this time, the module connector 430 can be attached by being coupled to the first sealing cover 420 via a coupling member 440. At least a portion of the module connector 430 can be exposed to the outside of a first end plate 510, which will be described later, and the first end plate 510 may be provided with a module connector opening 530 for this purpose.

[0112] The first sealing cover 420 may be provided with a terminal bus bar 340. The terminal bus bar 340 may include a first terminal bus bar 341 and a second terminal bus bar 343, and the first terminal bus bar 341 and the second terminal bus bar 343 may have opposite polarities.

[0113] The terminal bus bar 340 may be electrically connected to a bus bar or an electrode lead to electrically connect one battery assembly 100 to another battery assembly 100. To connect one battery assembly 100 to another external battery assembly 100, at least a portion of the terminal bus bar 340 may be exposed to the outside of a first end plate 510 (described later), and the end plate 500 may be provided with a terminal bus bar opening 520 for this purpose.

[0114] The terminal bus bar 340 may further include a protrusion protruding from the outer surface of the first sealing cover 420. The protrusion may be exposed to the outside of the battery assembly 100 through a terminal bus bar opening 520, which will be described later. The terminal bus bar 340 may be connected to another battery assembly 100 or a BDU (Battery Disconnect Unit) through the protrusion exposed through the terminal bus bar opening 520 to form a high voltage (HV) connection.

[0115] 12(a), (b) and (c) are diagrams showing the process of assembling the first sealing assembly of FIG.

[0116] 3, 11, and 12(a), (b), and (c), a module connector 430 is attached to one side of the first sealing assembly 410, and a sensing unit 360 is attached to the other side of the first sealing assembly 410, so that the module connector 430 and the sensing unit 360 can be electrically connected to each other. Specifically, the module connector 430 can be attached to an outer surface 420a of the first sealing cover 420. The outer surface 420a of the first sealing cover 420 is the surface facing the first end plate 510 and may be the surface opposite the surface facing the first bus bar assembly 300a.

[0117] 12(a), the module connector 430 may be mounted in a mounting area MA, which is a region on the outer surface 420a of the first sealing cover 420. The mounting area MA is a region corresponding to the size of the module connector 430. A hole penetrating the first sealing cover 420 may be provided in the center of the mounting area MA, and a groove into which the coupling member 440 can be mounted may be provided at the apex of the mounting area MA. In this case, the coupling member 440 may be provided at the apex of the module connector 430, and the coupling member 440 may be located in a region corresponding to the groove in the mounting area MA. Therefore, the coupling member 440 can be coupled to the groove in the mounting area MA, allowing the module connector 430 to be mounted in the mounting area MA.

[0118] The coupling member 440 may be any member that couples and secures the module connector 430 to the mounting area MA, and may be, for example, a bolt and nut or a rivet.

[0119] 12(b) and 12(c), the sensing unit 360 may be attached to one surface of the first sealing cover 420. Specifically, the sensing unit 360 may be attached to the inner surface 420b of the first sealing cover 420. The inner surface 420b of the first sealing cover 420 is the surface facing the first bus bar assembly 300a and may be the surface opposite the surface facing the first end plate 510.

[0120] The sensing unit 360 may include a sensing printed circuit board 361 and a sensing cable 363 electrically connected to the sensing printed circuit board 361. The sensing printed circuit board 361 may be electrically connected to the module connector 430. The sensing printed circuit board 361 may be located in an area corresponding to the module connector 430. Specifically, the sensing printed circuit board 361 may be located in the mounting area MA. The sensing printed circuit board 361 may be located so as to be electrically connected to the module connector 430 through a hole in the mounting area MA.

[0121] The sensing cable 363 is a cable electrically connected to the sensing printed circuit board 361 and may include a cable connecting portion 363a and a cable extending portion 363b.

[0122] The cable connection portion 363a may be connected to the sensing printed circuit board 361 and positioned in contact with the inner surface 420b of the first sealing cover 420. The cable connection portion 363a is fixed in contact with the inner surface 420b of the first sealing cover 420 and does not move freely within the battery assembly 100, preventing damage to components.

[0123] Specifically, the cable connecting portion 363a may extend from the sensing printed circuit board 361 to the lower portion of the first sealing cover 420 and bend and extend from the lower portion of the first sealing cover 420. In this case, the portion bent and extending from the cable connecting portion 363a at the lower portion of the first sealing cover 420 may be defined as a cable extension portion 363b. The cable extension portion 363b may be electrically connected to the first flexible printed circuit board 350 located in the bus bar assembly.

[0124] 13(a), (b) and (c) are diagrams showing the process of mounting the first sealing assembly of FIG. 11 on one side of the frame.

[0125] 12(c) and 13(a) together, the sensing cable 363 can be electrically connected to the first flexible printed circuit board 350. In this case, the sensing cable 363 can transmit voltage information and temperature information of the battery cell acquired from the flexible printed circuit board 350 to the sensing printed circuit board 361. In this case, the sensing printed circuit board 361 can transmit the information acquired from the flexible printed circuit board 350 to the module connector 430. That is, the sensing unit 360 can transmit the battery cell data acquired from the flexible printed circuit board 350 to the module connector 430.

[0126] Therefore, the module connector 430 can transmit data acquired from the flexible printed circuit board 350 and the sensing unit 360 to a BMS (Battery Management System), and the BMS can control the charging and discharging of the battery cells based on the collected voltage data.

[0127] 3 and 13(a) and (b), the first sealing cover 420 can be attached to the frame 200 by covering one open side of the frame 200. As an example, the first sealing cover 420 can be mated with the frame 200. In this case, the periphery of the first sealing cover 420 can include a protrusion that protrudes in the direction of mating with the frame 200 (-X-axis direction). The periphery of the frame 200 mated with the first sealing cover 420 can be formed with a step so that the protrusion on the periphery of the first sealing cover 420 can be mated with it. Therefore, the first sealing cover 420 and the frame 200 can be mated with each other.

[0128] 13(c), when the first sealing cover 420 is coupled to the open side of the frame 200, a first sealing member 610 may be interposed along the periphery of the first sealing cover 420 and the frame 200. When the first sealing cover 420 and the frame 200 are coupled together, a small gap may occur between them due to assembly tolerances, and the first sealing member 610 may seal the gap to improve the sealing performance of the battery assembly 100. This prevents leakage of the refrigerant located inside the battery assembly 100, prevents leakage of gas generated inside the battery assembly 100, and controls the direction of gas discharge, thereby improving the safety of the battery assembly 100. In this case, the first sealing member 610 may be, for example, an adhesive tape.

[0129] Although not specifically shown, after the first sealing assembly 410 is coupled to the frame 200 and the periphery is sealed with the first sealing member 610, any gaps present in the first sealing assembly 410 can be sealed with a second sealing member 620 (see FIG. 16). This is to ensure that the second sealing member 620 seals portions of the first sealing assembly 410 other than the periphery that cannot be sealed with the first sealing member 610, thereby further improving the sealing performance of the battery assembly 100. The second sealing member 620 will be described in more detail with reference to FIG. 16.

[0130] FIG. 14 is an exploded perspective view showing a first end plate being attached to a first sealing assembly according to one embodiment of the present invention.

[0131] 11, 13, and 14, in a battery assembly 100 according to an embodiment of the present invention, a first end plate 510 may be positioned to cover a first sealing assembly 410. A terminal bus bar opening 520, a module connector opening 530, and an inlet opening 540 may be formed in the first end plate 510.

[0132] The terminal bus bar opening 520 may be an opening formed in an area corresponding to the position of the terminal bus bar 340 provided in the first sealing assembly 410. The terminal bus bar opening 520 may protrude from the first end plate 510 toward the outside of the battery assembly 100, and only the top surface of this protruding shape may be open. A portion of the terminal bus bar 340 may be exposed to the outside through this open portion.

[0133] The size of the terminal bus bar opening 520 can be determined mainly by the size around the terminal bus bar 340. However, for ease of assembly or for reasons of the manufacturing process, the size of the terminal bus bar opening 520 may be larger than the size of the exposed portion of the terminal bus bar 340, and in this case, a gap may occur between the terminal bus bar opening 520 and the terminal bus bar 340 exposed to the outside.

[0134] The module connector opening 530 and the inlet opening 540 are openings provided in the first end plate 510, and are holes that penetrate the first end plate 510. Specifically, the module connector opening 530 may be an opening formed in an area corresponding to the position of the module connector 430 provided in the first sealing assembly 410, and the inlet opening 540 may be an opening formed in an area corresponding to the position of the inlet 421 provided in the first sealing assembly 410. As a result, even when the first end plate 510 is attached, at least a portion of the module connector 430 and the inlet 421 can be exposed to the outside through the module connector opening 530 and the inlet opening 540, respectively.

[0135] The sizes of the module connector opening 530 and the inlet opening 540 can be determined by the periphery of the module connector 430 and the inlet 421. However, for ease of assembly or for reasons of the manufacturing process, the sizes of the module connector opening 530 and the inlet opening 540 may be larger than the sizes of the exposed portions of the module connector 430 and the inlet 421. In this case, gaps may occur between the module connector opening 530 and the exposed portion of the module connector 430, and between the inlet opening 540 and the exposed portion of the inlet 421.

[0136] The terminal bus bar 340 and the module connector 430 are exposed to the outside through the terminal bus bar opening 520 and the module connector opening 530, respectively, which allows for easy HV and LV connections to external electrical components, thereby improving the efficiency of the assembly process.

[0137] Since the inlet 421 is exposed to the outside of the battery assembly 100 through the inlet opening 540, when the refrigerant flows in through the inlet 421, leakage of the refrigerant between the first sealing assembly 410 and the first end plate 510 can be prevented. Therefore, the refrigerant does not come into contact with the terminal bus bar 340 or the module connector 430, which electrically connect to the outside. In other words, short circuits between the above components can be prevented, thereby improving the safety of the battery assembly 100.

[0138] A third sealing member 630 may be interposed between the first end plate 510 and the first sealing assembly 410. The third sealing member 630 may have a shape corresponding to the periphery of the first sealing assembly 410 or the periphery of the first end plate 510. The third sealing member 630 may be a resin that is applied to correspond to the periphery of the first sealing assembly 410 or the periphery of the first end plate 510 and then hardened. Specifically, the third sealing member 630 may be applied to a first groove 411, which is a groove formed along the periphery of the first sealing assembly 410, and hardened after the first sealing assembly 410 and the first end plate 510 are joined together. For example, the third sealing member 630 may include an epoxy resin.

[0139] That is, by interposing the third sealing member 630 between the first sealing assembly 410 and the first end plate 510, the first sealing assembly 410 and the first end plate 510 can be joined and sealed without any gaps formed due to assembly tolerances. Therefore, the sealing performance of the battery assembly 100 is improved, and leakage of the refrigerant located within the battery assembly 100 is prevented, thereby improving the cooling performance of the battery assembly 100. In addition, the venting direction can be adjusted while preventing venting gas generated within the battery assembly 100 above a certain temperature and pressure from being discharged to the outside through the gaps, thereby improving the safety of the battery assembly 100.

[0140] The type and method of forming the third sealing member 630 are not limited to those described above, and may be in the form of a gasket made of an elastic material, or any other material that serves to seal the first sealing assembly 410 and the first end plate 510.

[0141] Fig. 15 is a diagram of the configuration excluding the first end plate in Fig. 14, viewed in the -x-axis direction on the yz plane. Fig. 16 is a partial cross-sectional view showing an enlarged portion corresponding to "C" in the cross section taken along the cutting line B-B' in Fig. 15.

[0142] 14 to 16, a first sealing member 610 and a third sealing member 630 are positioned along the periphery of the first sealing assembly 410, and a second sealing member 620 may be positioned in one region of the first sealing assembly 410.

[0143] 16 , the second sealing member 620 may be located in an area of ​​the first sealing assembly 410 excluding the peripheral area. That is, the second sealing member 620 may seal the remaining area of ​​the first sealing assembly 410 that the first sealing member 610 and the third sealing member 630 cannot cover. Specifically, the second sealing member 620 may seal a gap in the first sealing assembly 410. However, the area in which the second sealing member 620 is located is not limited to the area shown in this drawing. For example, the second sealing member 620 may seal a gap in a region of the first sealing assembly 410 to which the module connector 430 is coupled.

[0144] Since the second sealing member 620 seals not only the peripheral portion of the first sealing assembly 410 but also the portion where the gap is located, the sealing performance of the battery assembly 100 is improved and leakage of the refrigerant inside the battery assembly 100 is prevented. This improves the cooling performance of the battery assembly 100. In addition, since gas generated inside the battery assembly 100 above a certain temperature and pressure is not discharged between the gap between the first sealing assembly 410 and the first end plate 510, the safety of the battery assembly 100 is improved.

[0145] FIG. 17 shows a second sealing assembly according to an embodiment of the present invention mounted on the other side of the frame.

[0146] 2, 3, 6 and 17, the second bus bar assembly 300b may be located on the other side of the battery cell stack 120, as described above.

[0147] The second bus bar assembly 300b may include a second bus bar frame 310b and a second bus bar 330b attached to the second bus bar frame 310b.

[0148] The second bus bar frame 310b may be located on the other side of the battery cell stack 120 to cover the other side of the battery cell stack 120 and also to guide the connection between the battery cell stack 120 and an external device.

[0149] The second bus bar frame 310b may have a second bus bar 330b attached thereto. For example, the inner surface of the second bus bar frame 310b may face the battery cell stack 120, and the second bus bar 330b may be attached to the outer surface of the second bus bar frame 310b.

[0150] The second bus bar frame 310b may include an electrically insulating material. The second bus bar frame 310b may prevent electrical shorts by restricting contact of the second bus bars 330b with other parts of the battery cells 110 other than the parts joined with the electrode leads (not shown). The second bus bars 330b may be attached to the outer surface of the second bus bar frame 310b and may electrically connect the battery cells 110 included in the battery cell stack 120.

[0151] The second bus bar 330b may be electrically connected to the battery cell stack 120 via the electrode leads 130 of the battery cells 110. Specifically, the electrode leads 130 of the battery cells 110 may pass through slits formed in the second bus bar frame 310b, bend, and connect to the second bus bar 330b. The second bus bar 330b may electrically connect the battery cells 110 included in the battery cell stack 120 in series or parallel. There are no particular limitations on the connection method between the electrode leads 130 and the second bus bar 330b, and welding may be used, for example.

[0152] Meanwhile, the battery assembly 100 according to this embodiment may include a second sealing assembly 450 attached to the other open side of the frame 200. The second sealing assembly 450 may be attached to cover the second bus bar assembly 300b.

[0153] The second sealing assembly 450 may include a second sealing cover 460 which is a plate covering the other open surface of the frame 200 , and an outlet 461 which is a hole formed in the second sealing cover 460 .

[0154] The second sealing cover 460 is a plate that covers the other open side of the frame 200, and may have a size corresponding to the size of the other open side of the frame 200. That is, the second sealing cover 460 may be attached to the frame 200 while covering the other open side of the frame 200. For example, the second sealing cover 460 may be mated with the frame 200.

[0155] The outlet 461 may be a hole formed in one region of the second sealing cover 460. The outlet 461 may be a hole that protrudes toward the outer surface (-X-axis direction) of the second sealing cover 460. That is, the outlet 461 may be a hole that protrudes in the opposite direction to the position of the frame 200 based on the second sealing cover 460. The protruding outlet 461 may pass through an outlet opening 560 formed in a second end plate 550, which will be described later.

[0156] The outlet 461 may be located above the center of the height of the battery cell stack 120. The outlet 461 may be located near the upper end of the second sealing assembly 450. Specifically, the outlet 461 may be located above the center of the height of the second sealing assembly 450.

[0157] When the second sealing assembly 450 and the other open side of the frame 200 are coupled to each other, a first sealing member 610 may be interposed along the periphery of the second sealing cover 460 and the frame 200. When the second sealing cover 460 and the frame 200 are coupled together, a small gap may occur between them due to assembly tolerances, and this gap may be sealed with the first sealing member 610 to improve the sealing performance of the battery assembly 100. This prevents leakage of the refrigerant located inside the battery assembly 100, prevents leakage of venting gas generated inside the battery assembly 100, and controls the direction of gas discharge, thereby improving the safety of the battery assembly 100. In this case, the first sealing member 610 may be, for example, an adhesive tape.

[0158] Although not specifically shown, after the second sealing assembly 450 is coupled to the frame 200 and the periphery is sealed with the first sealing member 610, any gaps present on the second sealing assembly 450 can be sealed with the second sealing member 620 (see FIG. 20). This is to ensure that portions of the second sealing assembly 450 other than the periphery that cannot be sealed with the first sealing member 610 are sealed using the second sealing member 620, thereby further improving the sealing performance of the battery assembly 100. The second sealing member 620 will be described in more detail with reference to FIG. 20.

[0159] FIG. 18 is an exploded perspective view showing a second end plate being attached to a second sealing assembly according to one embodiment of the present invention.

[0160] 18, in a battery assembly 100 according to an embodiment of the present invention, a second end plate 550 may be positioned to cover a second sealing assembly 450. An outlet opening 560 may be formed in the second end plate 550.

[0161] The outlet opening 560 is an opening provided in the second end plate 550, and is a hole that penetrates the second end plate 550. Specifically, the outlet opening 560 may be an opening formed in an area corresponding to the position of the outlet 461 provided in the second sealing assembly 450. As a result, even when the second end plate 550 is attached, at least a portion of the outlet 461 can pass through the outlet opening 560 and be exposed to the outside.

[0162] The size of the outlet opening 560 can be determined mainly by the size of the circumference of the outlet 461. However, for ease of assembly or for reasons of the manufacturing process, the size of the outlet opening 560 may be larger than the size of the exposed portion of the outlet 461, and in this case, a gap may occur between the outlet 461 exposed outside the outlet opening 560.

[0163] Since the outlet 461 is exposed to the outside of the battery assembly 100 through the outlet opening 560, when the refrigerant that has flowed into the frame 200 is discharged to the outside through the outlet 461, the refrigerant can be prevented from leaking between the second sealing assembly 450 and the second end plate 550. Therefore, the refrigerant does not come into contact with other electrical components, preventing the occurrence of a short circuit, and improving the safety of the battery assembly 100.

[0164] A third sealing member 630 may be interposed between the second end plate 550 and the second sealing assembly 450. The third sealing member 630 may have a shape corresponding to the periphery of the second sealing assembly 450 or the periphery of the second end plate 550. The third sealing member 630 may be a resin that is applied to correspond to the periphery of the second sealing assembly 450 or the periphery of the second end plate 550 and then hardened. Specifically, the third sealing member 630 may be applied to a second groove 451, which is a groove formed along the periphery of the second sealing assembly 450, and hardened after the second sealing assembly 450 and the second end plate 550 are joined together. For example, the third sealing member 630 may include an epoxy resin.

[0165] That is, by interposing the third sealing member 630 between the second sealing assembly 450 and the second end plate 550, the second sealing assembly 450 and the second end plate 550 can be joined and sealed without any gaps formed due to assembly tolerances. Therefore, the sealing performance of the battery assembly 100 is improved, and leakage of the refrigerant located within the battery assembly 100 is prevented, thereby improving the cooling performance of the battery assembly 100. In addition, the venting direction can be adjusted while preventing venting gas generated within the battery assembly 100 above a certain temperature and pressure from being discharged to the outside through the gaps, thereby improving the safety of the battery assembly 100.

[0166] The type and method of forming the third sealing member 630 are not limited to those described above, and may be in the form of a gasket made of an elastic material, or any other material that serves to seal the second sealing assembly 450 and the second end plate 550.

[0167] Fig. 19 is a diagram of the configuration in Fig. 18 excluding the second end plate, viewed in the x-axis direction on the yz plane. Fig. 20 is a partial cross-sectional view showing an enlarged portion corresponding to "E" in the cross section taken along the cutting line DD' in Fig. 19.

[0168] 18 to 20, a first sealing member 610 and a third sealing member 630 are positioned along the periphery of the second sealing assembly 450, and a second sealing member 620 may be positioned in one region of the second sealing assembly 450.

[0169] 20 regarding the second sealing member 620, the second sealing member 620 may be located in an area excluding the peripheral area of ​​the second sealing assembly 450. That is, the second sealing member 620 may seal the remaining area of ​​the second sealing assembly 450 that cannot be covered by the first sealing member 610 and the third sealing member 630. Specifically, the second sealing member 620 may seal an area of ​​the first sealing assembly 410 where there is a gap. However, the area where the second sealing member 620 is located is not limited to the area shown in this drawing.

[0170] Since the second sealing member 620 seals not only the peripheral portion of the second sealing assembly 450 but also the portion where the gap is located, the sealing performance of the battery assembly 100 is improved and leakage of the refrigerant inside the battery assembly 100 is prevented. This improves the cooling performance of the battery assembly 100. In addition, since gas generated inside the battery assembly 100 above a certain temperature and pressure is not discharged between the gap between the second sealing assembly 450 and the second end plate 550, the safety of the battery assembly 100 is improved.

[0171] Hereinafter, a battery assembly according to a modified embodiment of the present invention will be described in detail with reference to FIGS.

[0172] Fig. 21 is an exploded perspective view of a battery cell stack, a first busbar assembly, and a second busbar assembly according to a modified embodiment of the present invention. Fig. 22 is a front view of a battery assembly according to a modified embodiment of the present invention with the first end plate and the first busbar frame removed. Fig. 23 is an enlarged partial view of part "F" in Fig. 22.

[0173] 21 to 23, a battery assembly according to a modified embodiment of the present invention includes a battery cell stack 120 in which a plurality of battery cells 110 are stacked, and a frame 200 in which the battery cell stack 120 is housed and which includes a first side portion 210, a second side portion 220, a ceiling portion 230, and a bottom portion 240. Although not specifically shown, the battery assembly according to the modified embodiment of the present invention may also include an inlet and an outlet, a first bus bar assembly 300a, a second bus bar assembly 300b, a flexible printed circuit board 350, etc. In other words, the battery assembly according to this embodiment may have the same or similar structure as the battery assembly described with reference to FIGS. 2 to 6, except for a pad member 700b described below.

[0174] In this embodiment, a pad member 700 b is disposed at least at one location between the battery cells 110 , and at least one of the pad members 700 b extends from the ceiling portion 230 to the bottom portion 240 of the frame 200 .

[0175] However, the pad member 700b according to this embodiment may include a main pad 710 facing one side of the battery cell 110, a first vane 721 fitted between the main pad 710 and the ceiling portion 230 of the frame 200, and a second vane 722 fitted between the main pad 710 and the bottom portion 240 of the frame 200.

[0176] The main pad 710 absorbs swelling of the battery cells 110 and may be made of any material, including, but not limited to, polyurethane, as an example. The first vane 721 and the second vane 722 may also be made of any material, including, but not limited to, the same material as the main pad 710. Unlike the pad member 700a, which is a single pad, the pad member 700b according to this embodiment has the first vane 721 and the second vane 722 disposed above and below the main pad 710, thereby forming separated refrigerant flow paths FP between the pad members 700b. That is, although the pad member 700b according to this embodiment is divided into multiple members, its overall shape is the same as the pad member 700a described above, and therefore it can similarly perform the function of forming the refrigerant flow paths FP and eliminating refrigerant flow stagnation and resulting cooling imbalance.

[0177] Even if the height of the battery cells 110 or the height of the frame 200 are different, in the case of the pad member 700b according to this embodiment, the main pad 710 can be used as is by simply changing the first vane 721 or the second vane 722 to fit the different height dimensions. In other words, compared to the previous embodiment in which the entire pad member 700a had to be replaced, the embodiment of the pad member 700b according to this embodiment may be advantageous in terms of the manufacturing process.

[0178] In this embodiment, terms indicating directions such as front, back, left, right, up, and down are used, but these terms are used merely for convenience of explanation and may vary depending on the position of the object of interest, the position of the observer, etc.

[0179] One or more battery assemblies according to the present embodiment can be directly mounted on a vehicle or chassis by themselves. That is, in the case of the battery assembly 100 according to the present embodiment, the battery cells 110 can be directly mounted on a vehicle or chassis with the battery cells 110 housed in the frame 200.

[0180] As another example, a battery assembly may be installed 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.

[0181] The battery assembly of the present invention can be applied to various devices, specifically, transportation means such as electric bicycles, electric cars, and hybrids, and ESS (Energy Storage Systems), but is not limited thereto, and can be applied to various devices that can use secondary batteries.

[0182] Although the 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 made by those skilled in the art using the basic concept of the present invention defined in the following claims also fall within the scope of the present invention. [Explanation of symbols]

[0183] 100: Battery assembly 110: Battery cell 120: Battery cell stack 200: Frame 210:First side part 220:Second side part 230: Ceiling 240: Bottom 300a: First bus bar assembly 300b: Second bus bar assembly 421: Inlet 461:Outlet 700a, 700b: pad members 710: Main pad 721: First vane 722: Second vane

Claims

1. a battery cell stack in which a plurality of battery cells are stacked; a frame that houses the battery cell stack and includes a first side surface, a second side surface, a ceiling surface, and a bottom surface; an inlet and an outlet for circulating a coolant inside the frame; The refrigerant flows into the frame through the inlet and is discharged through the outlet, a pad member is disposed at at least one location between the plurality of battery cells; At least one of the pad members extends from the ceiling to the bottom of the frame.

2. The battery assembly according to claim 1 , wherein the cooling medium passages are separated from one another between the pad members.

3. The battery assembly according to claim 1 , wherein at least one upper end of the pad member is in close contact with the ceiling portion, and at least one lower end of the pad member is in close contact with the bottom portion.

4. 2. The battery assembly according to claim 1, wherein the pad member is a single pad extending from the ceiling to the bottom of the frame.

5. 2. The battery assembly according to claim 1, wherein the pad member includes: a main pad facing one side of the battery cell; a first vane fitted between the main pad and the ceiling portion of the frame; and a second vane fitted between the main pad and the bottom portion of the frame.

6. The battery assembly according to claim 1 , wherein the inlet and the outlet are located on opposite sides of the battery cell stack.

7. The battery assembly according to claim 1 , further comprising a first end plate and a second end plate covering the open sides of the frame, respectively.

8. the inlet is provided in the first end plate, The battery assembly according to claim 7 , wherein the outlet is provided in the second end plate.

9. the inlet is located below the center of the battery cell stack based on the height of the battery cell stack; The battery assembly according to claim 1 , wherein the outlet is located above a center of the height of the battery cell stack.

10. In a first direction and a second direction that are parallel to the direction in which the plurality of battery cells are stacked and are opposite to each other, the inlet is positioned offset in the first direction from a center of the battery cell stack in a direction in which the plurality of battery cells are stacked; The battery assembly according to claim 1 , wherein the outlet is positioned offset in the second direction from a center of the battery cell stack in a direction in which the plurality of battery cells are stacked.

11. The battery assembly according to claim 1 , wherein in the battery cell stack, the plurality of battery cells are stacked along a direction from the first side portion of the frame to the second side portion of the frame.

12. The battery assembly according to claim 1 , wherein the plurality of battery cells are stacked with one surface of each battery cell parallel to the first side surface and the second side surface.

13. The battery assembly according to claim 1 , wherein the refrigerant is insulating oil.

14. The battery assembly according to claim 1 , wherein the coolant cools the battery cell stack housed inside the frame by direct contact with the battery cell stack.

15. The pad member is provided in plurality, The battery assembly according to claim 1 , wherein the pad members are arranged at predetermined intervals along a direction in which the battery cells are stacked.

16. The battery assembly according to claim 1 , wherein the pad member is further disposed between the battery cell stack and the first side portion.

17. The battery assembly according to claim 1 , wherein the pad member is further disposed between the battery cell stack and the second side portion.

18. Further comprising cooling fins positioned between the plurality of battery cells; The battery assembly according to claim 1 , wherein the cooling fins extend to and contact the ceiling or the bottom.

19. A device including a battery assembly according to any one of claims 1 to 18.

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