Battery cell assembly and battery pack containing the same

Abstract

A battery cell assembly according to one embodiment of the present invention includes a subassembly comprising a battery cell stack formed by stacking a plurality of battery cells; a frame member housing the subassembly; and an interbus bar electrically connected to the battery cells included in the subassembly; a terminal member including one end having a screw thread formed thereon; a frame hole formed on at least one side of the frame member; and a terminal bus bar assembly covering the frame hole and connected to the terminal member, wherein an interbus bar hole is formed in the interbus bar, and one end of the terminal member is coupled to the interbus bar hole via the frame hole.

Description

Technical Field

[0001] [Cross - Reference to Related Applications] This application claims the benefit of priority based on Korean Patent Application No. 10 - 2024 - 0045811 filed on April 4, 2024 and Korean Patent Application No. 10 - 2025 - 0035933 filed on March 20, 2025, and all the contents disclosed in the documents of the Korean patent applications are included as part of this specification.

[0002] The present invention relates to a battery cell assembly and a battery pack including the same, and more specifically, to a battery cell assembly including a HV (High Voltage) electrical connection structure with improved cooling efficiency, safety, and sealing performance from the external environment, and a battery pack including the same.

Background Art

[0003] As the technology development and demand for mobile devices increase, the demand for secondary batteries as an energy source has been rapidly increasing. Accordingly, many studies on secondary batteries that can meet various requirements have been conducted.

[0004] Secondary batteries have attracted much attention not only as an energy source for mobile devices such as mobile phones, digital cameras, and notebook computers, but also as an energy source for power devices such as electric bicycles, electric vehicles, and hybrid electric vehicles.

[0005] In recent years, the need for a large - capacity secondary battery structure has increased, starting from the utilization of secondary batteries as an energy storage source, and the demand for battery packs with a medium - to - large - module structure in which a number of battery modules with multiple secondary batteries connected in series / parallel are assembled has been increasing.

[0006] On the other hand, when configuring a battery pack by connecting a plurality of battery cells in series / parallel, it is common to form a battery module consisting of at least one battery cell and add other components using at least one battery module to configure the battery pack.

[0007] The battery cells that make up such medium- and large-sized battery modules are composed of rechargeable secondary batteries, and such high-power, high-capacity secondary batteries generate a large amount of heat during the charging and discharging process. In this case, the heat from many battery cells is amplified in a confined space, causing the temperature to rise rapidly. In other words, while high output can be obtained in battery modules with many battery cells stacked on top of each other, and in battery packs equipped with such battery modules, it is not easy to remove the heat generated from the battery cells during charging and discharging. If the heat dissipation of the battery cells is not properly carried out, the battery cells will deteriorate more quickly, their lifespan will be shortened, and the possibility of explosion or fire will increase.

[0008] Furthermore, battery modules included in vehicle battery packs are frequently exposed to direct sunlight and may be subjected to high-temperature conditions such as summer or desert regions. Also, because a large number of battery modules are concentrated in order to extend the vehicle's driving range, flames or heat generated from one battery module can easily propagate to adjacent battery modules, potentially leading to ignition or explosion of the battery pack itself.

[0009] Furthermore, because battery packs consist of a structure that combines numerous battery modules, they are heavy and unsuitable for mounting many batteries in vehicles or other means of transportation, thus requiring an improvement in energy density.

[0010] Figure 1 is a perspective view showing a conventional battery pack. Figure 2 is an exploded perspective view of the battery pack shown in Figure 1.

[0011] Referring to Figures 1 and 2, a conventional battery pack 10 includes a lower pack frame 11 on which multiple battery modules 1 are mounted, an upper pack frame 12 located above the battery modules 1, and an internal beam 13 that demarcates the positions in which the battery modules 1 are mounted within the battery pack 10.

[0012] Thus, when battery modules 1 are installed inside a battery pack 10, the internal beams 13 that partition the battery modules 1 reduce the energy density of the battery pack 10. Therefore, in order to meet the efficiency requirements of a device, a larger number of battery packs 10 must be installed, which presented a problem. Furthermore, the weight of the battery pack 10 limited the number of battery packs 10 that could be installed in a device. Consequently, in order to reduce the weight of the battery pack 10 while simultaneously increasing its energy density, it was necessary to install a larger number of battery modules 1 inside the battery pack 10.

[0013] Figure 3 is a cross-sectional view showing one of the battery modules included in the battery pack shown in Figure 2.

[0014] Referring to Figure 3, a conventional battery module 1 includes a battery cell stack 3 containing battery cells 2 stacked in a predetermined direction, and a module frame 4 that houses the battery cell stack 3. The battery cell stack 3 is fixedly positioned on a thermally conductive resin layer 5 located on the lower surface of the module frame 4. In this case, a heat sink 6 located below the bottom of the module frame 4 may be provided to cool the heat generated from the battery cell stack 3.

[0015] However, the heatsink 6 does not directly contact the battery cell stack 3 and receive heat transfer in that manner, which has the disadvantage of not being very efficient at cooling. In particular, an air gap is formed between the bottom of the module frame 4 and the thermally conductive resin layer 5, which hinders heat transfer. Currently, there is a need for a more effective method to cool the battery module 1.

[0016] In summary, more effective methods are needed to improve the cooling efficiency of battery modules. [Overview of the Initiative] [Problems that the invention aims to solve]

[0017] The problem that the present invention aims to solve is to provide a battery cell assembly and a battery pack including the same, which include an HV (High Voltage) electrical connection structure that improves cooling efficiency and cooling performance and has sealing performance from the external environment.

[0018] The problems that this invention aims to solve are not limited to those described above, and any problems not mentioned will be clearly understood by a person with ordinary skill in the art to which this invention pertains from this specification and the accompanying drawings. [Means for solving the problem]

[0019] A battery cell assembly according to one embodiment of the present invention includes a subassembly comprising a battery cell stack formed by stacking a plurality of battery cells; a frame member housing the subassembly; and an interbus bar electrically connected to the battery cells included in the subassembly; a terminal member including one end having a screw thread formed thereon; a frame hole formed on at least one side of the frame member; and a terminal bus bar assembly covering the frame hole and connected to the terminal member, wherein an interbus bar hole is formed in the interbus bar, and one end of the terminal member is coupled to the interbus bar hole via the frame hole.

[0020] The terminal busbar assembly includes a terminal busbar electrically connected to the terminal member, and a terminal busbar frame made of an electrically insulating material that encloses at least a portion of the terminal busbar, with one end of the terminal busbar exposed to the outside of the terminal busbar frame, and the other end of the terminal busbar having a terminal busbar hole formed therein, and one end of the terminal member can pass through the terminal busbar hole and be coupled to the interbusbar hole.

[0021] The terminal member includes another end on which a screw thread is formed, and the other end of the terminal member can pass through the terminal busbar hole and be connected to a nut.

[0022] A gasket can be positioned between the nut connected to the other end of the terminal member and the terminal busbar hole.

[0023] A frame recess is formed on at least one side surface of the frame member, recessed from the outer surface of the frame member toward the interior of the frame member, and the frame hole is formed in the frame recess, and the size of the frame recess and the terminal busbar assembly may be the same as each other.

[0024] The space between the frame recess and the terminal busbar assembly may be filled with a sealing member.

[0025] The subassembly includes a first subassembly including a first battery cell stack and a second subassembly including a second battery cell stack, the interbusbars include a pair of first interbusbars electrically connected to the battery cells included in the first subassembly and a pair of second interbusbars electrically connected to the battery cells included in the second subassembly, the terminal members consist of a plurality of members electrically connected to the pair of first interbusbars and the pair of second interbusbars, respectively, and the pair of first interbusbars and the pair of second interbusbars can be located in the space between the first battery cell stack and the second battery cell stack, respectively.

[0026] The frame holes include a pair of first frame holes located on one side surface of the frame member and a pair of second frame holes located on the other side surface of the frame member. The terminal bus bar assembly includes a first terminal bus bar assembly covering the pair of first frame holes and a second terminal bus bar assembly covering the pair of second frame holes. The first terminal bus bar assembly is electrically connected to one of the pair of first inter-bus bars and one of the pair of second inter-bus bars, and the second terminal bus bar assembly is electrically connected to the other one of the pair of first inter-bus bars and the other one of the pair of second inter-bus bars.

[0027] It includes an inlet and an outlet for circulating a refrigerant inside the frame member. The refrigerant may flow into the inside of the frame member through the inlet and be discharged through the outlet.

[0028] The sub-assembly includes a first sub-assembly including a first battery cell stack and a second sub-assembly including a second battery cell stack. An insulating plate is disposed between the first sub-assembly and the second sub-assembly, and an opening through which the refrigerant passes may be formed in the insulating plate.

[0029] Based on the insulating plate, the inlet and the outlet are located on opposite sides of each other. The first sub-assembly may be located between the inlet and the insulating plate, and the second sub-assembly may be located between the outlet and the insulating plate.

[0030] The refrigerant flowing in through the inlet can pass through the first sub-assembly, the opening of the insulating plate, and the second sub-assembly in sequence and be discharged through the outlet.

[0031] The system further includes a first seal assembly and a second seal assembly, each covering the open sides of the frame member, wherein the inlet can be coupled to the first seal assembly and the outlet to the second seal assembly. The battery cell is a pouch-type battery cell and includes electrode leads protruding in both directions. If the direction between the electrode leads is defined as the longitudinal direction, the first seal assembly, the first subassembly, the insulating plate, the second subassembly, and the second seal assembly can be positioned in order along the longitudinal direction.

[0032] The refrigerant is an insulating oil, and the refrigerant can come into direct contact with the battery cell stack housed inside the frame member.

[0033] A battery pack according to another embodiment of the present invention may include the battery cell assembly described above. [Effects of the Invention]

[0034] According to the examples, the battery cell assembly and battery pack containing the same of the present invention can improve the cooling efficiency of the battery cell assembly and the battery pack containing the same by direct cooling of the battery cells with a refrigerant.

[0035] Furthermore, energy density can be increased by arranging multiple subassemblies along the length of the battery cell assembly, and the fluidity of the refrigerant can be improved by placing insulating freight with openings formed between the multiple subassemblies.

[0036] In addition, the electrical connection structure between the terminal busbar and the interbusbar includes a sealing structure, which ensures sealing performance for the HV (High Voltage) electrical connection structure from the external environment.

[0037] The effects of the present invention are not limited to those described above, and any effects not mentioned herein will be clearly understood by a person with ordinary skill in the art to which the present invention pertains from this specification and the accompanying drawings. [Brief explanation of the drawing]

[0038] [Figure 1] This is a perspective view showing a conventional battery pack. [Figure 2] Figure 1 is an exploded perspective view of the battery pack. [Figure 3] This is a cross-sectional view showing one of the battery cell assemblies included in the battery pack shown in Figure 2. [Figure 4] This is a perspective view of a battery cell assembly according to one embodiment of the present invention. [Figure 5] Figure 4 is a diagram showing the HV electrical connection structure with the top of the battery cell assembly as the reference point. [Figure 6] Figure 4 is an exploded perspective view showing the terminal busbar assembly, which is included in the battery cell assembly, in a separated state. [Figure 7] This is a magnified view of the second terminal busbar assembly in the battery cell assembly shown in Figure 4. [Figure 8] Figure 4 is an exploded perspective view showing the subassemblies and frame members included in the battery cell assembly separated. [Figure 9] Figure 4 is an exploded perspective view of the battery cell assembly with the frame members and end plates removed. [Figure 10] This is a magnified view of the area where the first and second interbus bars are located in Figure 9. [Figure 11] Figure 9 is an exploded perspective view of the subassembly. [Figure 12] Figure 11 is an exploded perspective view of the first subassembly. [Figure 13] Figure 12 is an exploded perspective view showing the first subassembly in isolation. [Figure 14] Figure 13 is a diagram showing a battery cell. [Modes for carrying out the invention]

[0039] Hereinafter, various embodiments of the present invention will be described in detail with reference to the attached drawings, so that those with ordinary skill in the art to which the present invention pertains can easily implement them. The present invention can be implemented in a variety of different forms and is not limited to the embodiments described herein.

[0040] To clearly explain the present invention, unnecessary parts have been omitted, and the same or similar reference numerals have been used throughout the specification for identical or similar components.

[0041] Furthermore, the dimensions and thicknesses of each component shown in the drawings are arbitrary for the sake of explanation, and therefore the present invention is not necessarily limited to those shown. In the drawings, thicknesses are shown enlarged to clearly represent various layers and regions. Also, in the drawings, the thicknesses of some layers and regions are shown exaggerated for the sake of explanation.

[0042] Furthermore, when a specification states that a certain part "includes" a certain component, unless otherwise stated, this means that it may include other components rather than excluding them.

[0043] Furthermore, throughout the specification, "on a plane" refers to the view of the subject from above, and "on a cross-section" refers to the view of a cross-section obtained by cutting the subject perpendicularly, as seen from the side.

[0044] The following describes a battery cell assembly 100 according to one embodiment of the present invention.

[0045] Figure 4 is a perspective view of a battery cell assembly according to one embodiment of the present invention. Figure 5 is a drawing showing the HV electrical connection structure with reference to the top of the battery cell assembly in Figure 4.

[0046] Referring to Figures 4 and 5, a battery cell assembly 100 according to one embodiment of the present invention includes a pair of subassemblies 100a and 100b, each consisting of a first subassembly 100a and a second subassembly 100b formed by stacking multiple battery cells 110 (Figure 12); a frame member 200 housing the subassemblies 100a and 100b; and an inlet 421 and an outlet 461 for circulating a coolant inside the frame member 200. The coolant, the inlet 421 and the outlet 461 will be described later.

[0047] Referring to Figure 4, the frame member 200 may be for protecting the first subassembly 100a, the second subassembly 100b, and the electrical components connected thereto from external physical shocks. The first subassembly 100a, the second subassembly 100b, and the electrical components connected thereto can be housed in the internal space of the frame member 200.

[0048] The structure of the frame member 200 is diverse. According to one embodiment of the present invention, the structure of the frame member 200 may be a monoframe structure. Here, the monoframe may be a form in which the top surface, bottom surface and both sides are integrated. As an example, the monoframe can be manufactured by injection molding.

[0049] The frame member 200 may be in an open configuration on both sides. More specifically, the frame member 200 can be provided in an open configuration along the longitudinal direction of the battery cell 110 (Figure 12). In this case, one side of the first subassembly 100a and the second subassembly 100b may not be obstructed by the frame member 200.

[0050] More specifically, the front and rear surfaces of the first battery cell stack 120a, shown in Figure 12, which is included in the first subassembly 100a, are shielded by the first front busbar assembly 301a, the first rear busbar assembly 302a, the seal assembly 400, or the end plate 500, which will be described later. As a result, the front and rear surfaces of the first battery cell stack 120a (Figure 12) should be protected from external physical shocks and the like. The above explanation was based on the first subassembly 100a, but the second subassembly 100b can be explained in a similar manner.

[0051] Referring to Figure 5, a battery cell assembly 100 according to one embodiment of the present invention may include a first terminal busbar assembly 350a and a second terminal busbar assembly 350b formed on both sides of a frame member, respectively.

[0052] More specifically, in the first terminal busbar assembly 350a, the first positive terminal busbar 352a and the first negative terminal busbar 353a may be exposed to the outside of the first terminal busbar frame 351a. Also, in the second terminal busbar assembly 350b, one end of the second positive terminal busbar 352b and one end of the second negative terminal busbar 353b may be exposed to the outside of the second terminal busbar frame 351b, respectively.

[0053] However, the positions of the first positive terminal busbar 352a and the first negative terminal busbar 353a are not limited to those shown in Figure 5, and may be changed from those shown in Figure 5. The same explanation can be given for the second positive terminal busbar 352b and the second negative terminal busbar 353b.

[0054] Furthermore, the first interbusbar 340a (Figure 11) included in the first subassembly 100a can be electrically connected to the other end of the first negative terminal busbar 353a in the first terminal busbar assembly 350a and to the other end of the second positive terminal busbar 352b in the second terminal busbar assembly 350b. Similarly, the second interbusbar 340b (Figure 11) included in the second subassembly 100b can be electrically connected to the other end of the first positive terminal busbar 352a in the first terminal busbar assembly 350a and to the other end of the second negative terminal busbar 353b in the second terminal busbar assembly 350b.

[0055] As a result, the first subassembly 100a can be connected to other battery cell assemblies and BDUs (Battery Disconnect Units) via one end of the first negative terminal busbar 353a exposed to the outside from the first terminal busbar assembly 350a and one end of the second positive terminal busbar 352b exposed to the outside from the second terminal busbar assembly 350b, thereby forming a high-voltage (HV) connection with them. Similarly, the second subassembly 100b can be connected to other battery cell assemblies and BDUs (Battery Disconnect Units) via one end of the first positive terminal busbar 352a exposed to the outside from the first terminal busbar assembly 350a and one end of the second negative terminal busbar 353b exposed to the outside from the second terminal busbar assembly 350b, thereby forming a high-voltage (HV) connection with them.

[0056] In the first terminal busbar assembly 350a, one end of the first positive terminal busbar 352a and one end of the first negative terminal busbar 353a can be positioned adjacent to each other, and the first terminal busbar assembly 350a can have a size of a first width (d1) along the length direction of the frame member 200. In the second terminal busbar assembly 350b, one end of the second positive terminal busbar 352b and one end of the second negative terminal busbar 353b are separated from each other by a second distance (d2), and the second terminal busbar frame 351b may have a space formed between one end of the second positive terminal busbar 352b and one end of the second negative terminal busbar 353b.

[0057] Here, the first width (d1) of the first terminal busbar assembly 350a may be smaller than the second distance (d2) between the second positive terminal busbar 352b and the second negative terminal busbar 353b in the second terminal busbar assembly 350b.

[0058] As a result, the battery cell assembly 100 according to this embodiment is arranged along the width direction of the frame member 200 together with other battery cell assemblies 100, so that the first terminal busbar assembly 350a included in the battery cell assembly 100 according to this embodiment and the second terminal busbar assembly 350b included in the other battery cell assembly 100 are arranged to interlock with each other, which has the advantages of increased ease of assembly and space efficiency, as well as simplification of the HV electrical connection structure.

[0059] The connection structure between the terminal busbar assemblies 350a and 350b and the pair of subassemblies 100a and 100b will be described in more detail below.

[0060] Figure 6 is an exploded perspective view showing the terminal busbar assembly included in the battery cell assembly of Figure 4, separated from the original. Figure 7 is an enlarged view of the second terminal busbar assembly in the battery cell assembly of Figure 4.

[0061] Referring to Figure 6, a battery cell assembly 100 according to one embodiment of the present invention includes an interbusbar 340a, 340b (Figure 11) electrically connected to a battery cell 110 (Figure 12) contained in a pair of subassemblies 100a, 100b; terminal members 354a, 354b including one end with a threaded surface; frame hole 200H formed on at least one side of a frame member 200; and terminal busbar assemblies 350a, 350b that cover the frame hole 200H and are connected to the terminal members 354a, 354b.

[0062] More specifically, in the battery cell assembly 100 according to this embodiment, a frame recess portion 205 may be formed on at least one side surface of the frame member 200, which is recessed from the outer surface of the frame member 200 toward the interior of the frame member 200.

[0063] Furthermore, frame holes 200H may be formed in the frame recess 205. More specifically, the frame holes 200H include a pair of first frame holes located on one side of the frame member 200 and a pair of second frame holes located on the other side of the frame member 200, and the terminal busbar assemblies 350a, 350b may include a first terminal busbar assembly 350a covering the pair of first frame holes 200H and a second terminal busbar assembly 350b covering the pair of second frame holes 200H.

[0064] As an example, as shown in Figure 6, a pair of first frame holes 200H may be formed in the frame recess 205, and a pair of first terminal members 354a having different polarities can pass through the pair of frame holes 200H and be electrically connected to the interbus bars 340a and 340b (Figure 11) inside the frame member 200. Although Figure 6 is explained with reference to one side of the frame member 200, a second terminal member 354b can also be electrically connected to the interbus bars 340a and 340b (Figure 11) inside the frame member 200 for a pair of first frame holes 200H located on the other side of the frame member 200.

[0065] The frame recess 205 and the terminal busbar assemblies 350a and 350b may be the same size. More specifically, the space between the frame recess 205 and the terminal busbar assemblies 350a and 350b may be filled with sealing members 357a and 357b. That is, the sealing members 357a and 357b may be the same size as the frame recess 205 and / or the terminal busbar assemblies 350a and 350b. For example, the sealing members 357a and 357b may be made of the same material as the sealant, but are not limited to this, and any member having sealing performance and heat resistance may be included in this embodiment.

[0066] As a result, in the battery cell assembly 100 according to this embodiment, sealing members 357a and 357b are formed between the frame member 200 and the terminal busbar assemblies 350a and 350b, which improves the sealing performance between the frame member 200 and the terminal busbar assemblies 350a and 350b, as well as the sealing performance of the HV electrical connection structure.

[0067] Furthermore, as will be described later in Figures 9 to 14, the battery cell assembly 100 according to this embodiment has the advantage that insulating coolant can flow inside the frame member 200, and the sealing members 357a and 357b described above can effectively prevent leakage and leakage of insulating coolant.

[0068] Referring to Figures 6 and 7, the terminal busbar assemblies 350a, 350b include terminal busbars 352a, 353a, 352b, 353b that are electrically connected to terminal members 354a, 354b, and terminal busbar frames 351a, 351b made of electrically insulating material that enclose at least a portion of the terminal busbars 352a, 353a, 352b, 353b.

[0069] The following explanation will be based on the second terminal busbar assembly 350b, and the first terminal busbar assembly 350a can be explained similarly. More specifically, referring to Figures 6 and 7, the second terminal busbar assembly 350b may include a pair of second terminal busbars 352b, 353b, each electrically connected to a pair of second terminal members 354b, and a second terminal busbar frame 351b made of electrically insulating material that encloses at least a portion of the pair of second terminal busbars 352b, 353b.

[0070] Here, the pair of second terminal members 354b may have different polarities from each other, and the pair of second terminal busbars 352b and 353b may also have different polarities from each other. In this case, the pair of second terminal members 354b and the pair of second terminal busbars 352b and 353b can be electrically connected to each other with the same polarity.

[0071] Furthermore, the second terminal busbar frame 351b may be integrated with a pair of second terminal busbars 352b and 353b, or the pair of second terminal busbars 352b and 353b may be inserted inside the second terminal busbar frame 351b. For example, the second terminal busbar frame 351b can be manufactured together with the pair of second terminal busbars 352b and 353b by injection molding.

[0072] More specifically, as shown in Figures 6 and 7, one end 352b1, 353b1 of a pair of second terminal busbars 352b, 353b may be exposed to the outside of the second terminal busbar frame 351b. For example, one end 352b1, 353b1 of a pair of second terminal busbars 352b, 353b may be exposed on the top of the second terminal busbar frame 351b. However, the position of one end 352b1, 353b1 of a pair of second terminal busbars 352b, 353b is not limited to this, and any position that facilitates electrical connection with other battery cell assemblies 100 is included in this embodiment.

[0073] Furthermore, as shown in Figures 6 and 7, the other ends 352b2 and 353b2 of the pair of second terminal busbars 352b and 353b are formed with second terminal busbar holes 352bh and 353bh, respectively, and one end of the pair of second terminal members 354b, which have screw threads formed on them, can pass through the second terminal busbar holes 352bh and 353bh, respectively, and be connected to the interbusbar holes 345ah and 341bh (Figure 10) located inside the frame member.

[0074] Furthermore, as shown in Figures 6 and 7, the other end of the second terminal member 354b may also have a screw thread, and the other end of the second terminal member 354b can pass through the second terminal busbar holes 352bh and 353bh and be connected to the second nut 355b.

[0075] As a result, in the battery cell assembly 100 according to this embodiment, an electrical connection structure is stably formed between the interbusbars 340a and 340b (Figure 11) inside the frame member 200, which are made up of a pair of second terminal members 354b, and the pair of second terminal busbars 352b and 353b of the second terminal busbar assembly 350b, with the second terminal busbar assembly 350b as the reference.

[0076] The above explanation can also be applied to the first terminal busbar assembly 350a, and even with the first terminal busbar assembly 350a as the reference, a stable electrical connection structure is formed between the interbusbars 340a and 340b inside the frame member 200 (Figure 11) formed by the pair of first terminal members 354a and the pair of first terminal busbars 352a and 353a of the first terminal busbar assembly 350a.

[0077] Furthermore, in the battery cell assembly 100 according to this embodiment, the second terminal busbar assembly 350b may have a second gasket 356b positioned between the second nuts 355b, which are respectively coupled to the other ends of a pair of second terminal members 354b, and the second terminal busbar holes 352bh and 353bh. For example, the second gasket 356b may be made of the same material as a commonly used gasket, but is not limited thereto; any material having sealing performance and heat resistance is included in this embodiment. As another example, the second gasket 356b may have an O-ring shape, but is not limited thereto; any shape that can be easily coupled between each component is included in this embodiment.

[0078] As a result, in the battery cell assembly 100 according to this embodiment, the second gasket 356b is positioned between the second terminal busbar frame 351b and the pair of second terminal members 354b with respect to the second terminal busbar assembly 350b, thereby further improving the sealing performance between the frame member 200 and the second terminal busbar assembly 350b and the sealing performance of the HV electrical connection structure.

[0079] The above explanation can also be applied to the first terminal busbar assembly 350a, where the first gasket 356a is located between the first terminal busbar frame 351a and the pair of first terminal members 354a, thereby further improving the sealing performance between the frame member 200 and the first terminal busbar assembly 350a and the sealing performance of the HV electrical connection structure.

[0080] Figure 8 is an exploded perspective view showing the subassembly and frame members separated from the battery cell assembly in Figure 4. Figure 9 is an exploded perspective view showing the battery cell assembly in Figure 4 with the frame members and end plates removed. Figure 10 is an enlarged view of the area where the first and second interbus bars in Figure 9 are located. Figure 11 is an exploded perspective view of the subassembly in Figure 9. Figure 12 is an exploded perspective view of the first subassembly in Figure 11.

[0081] Referring to Figures 6, 9 to 11, in the battery cell assembly 100 according to this embodiment, the pair of subassemblies 100a and 100b include a first subassembly 100a containing a first battery cell stack 120a, and a second subassembly 100b containing a second battery cell stack 120b. Here, the interbus bars 340a and 340b may include a pair of first interbus bars 340a electrically connected to the battery cells 100 included in the first subassembly 100a, and a pair of second interbus bars 340b electrically connected to the battery cells 110 included in the second subassembly 100b. The pair of first interbus bars 340a and the pair of second interbus bars 340b can each be located in the space between the first battery cell stack 120a and the second battery cell stack 120b.

[0082] A pair of first interbusbars 340a may include a first positive interbusbar 341a and a first negative interbusbar 345a, and a pair of second interbusbars 340b may include a second positive interbusbar 341b and a second negative interbusbar 345b.

[0083] Here, the terminal members 354a and 354b are composed of multiple members and can be electrically connected to a pair of first interbusbars 340a and a pair of second interbusbars 340b, respectively. More specifically, the pair of first terminal members 354a can be electrically connected to a first negative interbusbar 345a and a second positive interbusbar 341b, and the pair of second terminal members 354b can be electrically connected to a first positive interbusbar 341a and a second positive interbusbar 345b.

[0084] Furthermore, the first terminal busbar assembly 350a can be electrically connected to one of the pair of first interbusbars 340a and one of the pair of second interbusbars 340b, and the second terminal busbar assembly 350b can be electrically connected to the other of the pair of first interbusbars 340a and the other of the pair of second interbusbars 340b. More specifically, the first terminal busbar assembly 350a can be electrically connected to the first negative interbusbar 345a and the second positive interbusbar 341b, and the second terminal busbar assembly 350b can be electrically connected to the first positive interbusbar 341a and the second negative interbusbar 345b.

[0085] Referring to Figure 10, in the battery cell assembly 100 according to this embodiment, a first negative electrode interbusbar hole 345ah may be formed in the first negative electrode interbusbar 345a, and a second positive electrode interbusbar hole 341bh may be formed in the second positive electrode interbusbar 341b. Although not shown in Figure 10, the first positive electrode interbusbar 341a and the second negative electrode interbusbar 345a can be described in the same manner.

[0086] One end of the terminal members 354a and 354b, as described in detail earlier, can be connected to the first negative electrode interbusbar hole 345ah and the second positive electrode interbusbar hole 341bh, respectively, via the frame hole 200H formed in the frame member 200. More specifically, one end of the pair of first terminal members 354a connected to the first terminal busbar assembly 350a can pass through the frame hole 200H and be connected to the first negative electrode interbusbar hole 345ah and the second positive electrode interbusbar hole 341bh, respectively. Although not shown in Figure 10, the first positive electrode interbusbar 341a and the second negative electrode interbusbar 345a can be described similarly.

[0087] As a result, in the battery cell assembly 100 according to this embodiment, an electrical connection structure can be stably formed between the interbus bars 340a and 340b located inside the battery cell assembly 100 and the terminal bus bar assemblies 350a and 350b located outside the battery cell assembly 100.

[0088] The following describes in detail a pair of subassemblies 100a and 100b included in the battery cell assembly 100 according to this embodiment. Most of the description will be based on the first subassembly 100a, but the second subassembly 100b can be described in the same manner. Figure 13 is an exploded perspective view showing the first battery cell stack from Figure 12 separated. Figure 14 is a drawing showing the battery cells from Figure 13.

[0089] Referring to Figures 8 and 12-14, the battery cell 110 is a pouch-type battery cell and may include electrode leads 130 protruding in both directions. Such a pouch-type battery cell can be formed by housing an electrode assembly in a pouch case made of a laminate sheet containing a resin layer and a metal layer, and then bonding the outer periphery of the pouch case. Such a battery cell 110 may have a rectangular sheet structure. Specifically, the battery cell 110 according to this embodiment has a structure in which two electrode leads 130 protrude from one end 114a and the other end 114b of the battery body 113, respectively. More specifically, the electrode leads 130 may protrude in opposite directions, and one of such electrode leads 130 may be a positive electrode lead and the other a negative electrode lead. In this embodiment, the direction between the electrode leads 130 protruding in both directions of the battery cell 110 is referred to as the longitudinal direction of the battery cell 110. As an example, referring to Figures 8 and 12-14, the direction parallel to the x-axis corresponds to the length direction of the battery cell 110.

[0090] The battery cell 110 can be manufactured by housing an electrode assembly (not shown) in the battery case 114 and bonding both ends 114a, 114b of the battery case 114 to a connecting side 114c. In other words, the battery cell 110 according to one embodiment of the present invention has a total of three sealing portions, the sealing portions are sealed by methods such as fusion bonding, and the remaining portion may consist of a folding portion 115.

[0091] Such a battery cell 110 is composed of multiple cells, and the multiple battery cells 110 are stacked so as to be electrically connected to each other to form battery cell stacks 120a and 120b. More specifically, the first subassembly 100a includes the first battery cell stack 120a, and the second subassembly 100b includes the second battery cell stack 120b.

[0092] In particular, the battery cells 110 may be stacked in one direction with the battery cells 110 standing upright and one side of the battery body 113 of the battery cells 110 facing each other. More specifically, as shown in Figures 8 and 12 to 14, the battery cells 110 are stacked in an upright position from one side of the frame member 200 to another, such that one side of the battery body 113 of the battery cell 110 is parallel to the side of the frame member 200. As an example, a diagram shows multiple battery cells 110 stacked in a direction parallel to the y-axis. When multiple battery cells 110 are stacked in a direction parallel to the y-axis in this way, the electrode leads 130 of a single battery cell 110 can protrude in the x-axis direction and the -x-axis direction, respectively.

[0093] Multiple battery cells 110 can be stacked in one region along a direction parallel to the y-axis to form a first battery cell stack 120a, and multiple battery cells 110 can be stacked in the other region along a direction parallel to the y-axis to form a second battery cell stack 120b.

[0094] The battery case 114 typically consists of a laminated structure of a resin layer / metal thin film layer / resin layer. For example, if the surface of the battery case consists of an O(oriented)-nylon layer, when stacking a large number of battery cells to form a medium-to-large battery cell assembly, it tends to easily slip due to external impacts. Therefore, in order to prevent this and maintain a stable stacked structure of the battery cells, an adhesive member such as double-sided tape or a chemical adhesive that bonds through a chemical reaction during bonding can be attached to the surface of the battery case to form a first battery cell stack 120a and a second battery cell stack 120b.

[0095] On the other hand, the first battery cell stack 120a and the second battery cell stack 120b are positioned along a direction perpendicular to the direction in which the battery cells 110 are stacked in the first battery cell stack 120a and the second battery cell stack 120b. More specifically, the first battery cell stack 120a and the second battery cell stack 120b are positioned along the direction in which the electrode leads 130 protrude from the battery cell 110. In other words, the first battery cell stack 120a and the second battery cell stack 120b are positioned along the length direction of the battery cell 110. For example, as shown in Figure 10, when multiple battery cells 110 are stacked along a direction parallel to the y-axis to form the first battery cell stack 120a and the second battery cell stack 120b, the first battery cell stack 120a and the second battery cell stack 120b can be positioned along a direction parallel to the x-axis.

[0096] Referring to Figures 11 and 12, the battery cell assembly 100 according to this embodiment may include a first subassembly 100a and a second subassembly 100b arranged along the longitudinal direction of the battery cell 110. Specifically, the battery cell assembly 100 according to this embodiment may have the first subassembly 100a and the second subassembly 100b, which are located inside the frame member 200, electrically coupled, or they may be individually mounted inside the frame member 200. In other words, the battery cell assembly 100 according to this embodiment corresponds to a twin model battery cell assembly having a first subassembly 100a and a second subassembly 100b.

[0097] Here, the first subassembly 100a includes a first battery cell stack 120a and first busbar assemblies 301a and 302a, and the second subassembly 100b may include a second battery cell stack 120b and second busbar assemblies 301b and 302b. Here, the first battery cell stack 120a and the second battery cell stack 120b are arranged along the longitudinal direction of the battery cell 110.

[0098] Furthermore, the first subassembly 100a can have the first busbar assemblies 301a and 302a positioned on the front and rear surfaces of the first battery cell stack 120a, respectively, and the second subassembly 100b can have the second busbar assemblies 301b and 302b positioned on the front and rear surfaces of the second battery cell stack 120b, respectively.

[0099] More specifically, the first busbar assemblies 301a and 302a can be positioned in the direction in which the electrode leads 130 of the battery cells 110 contained in the first battery cell stack 120a protrude. Similarly, the second busbar assemblies 301b and 302b can be positioned in the direction in which the electrode leads 130 of the battery cells 110 contained in the second battery cell stack 120b protrude. The first busbar assemblies 301a and 302a and the second busbar assemblies 301b and 302b can each include a busbar frame, busbars, and terminal busbars, respectively, which will be described later.

[0100] Referring to Figures 8 and 9, the battery cell assembly 100 according to this embodiment may include a seal assembly 400. The seal assembly 400 is located on both open sides of the frame member 200 and can be formed to cover a pair of subassemblies 100a and 100b. The seal assembly 400 located on one open side of the frame member 200 may be a first seal assembly 410, and the seal assembly 400 located on the other open side of the frame member 200 may be a second seal assembly 450. That is, the battery cell assembly 100 according to this embodiment may further include a first seal assembly 410 and a second seal assembly 450 that cover both open sides of the frame member 200, respectively.

[0101] The seal assembly 400 can isolate the open sides of the frame member 200 from the external environment. Specifically, when a refrigerant is injected into the frame member 200, the seal assembly 400 can seal the refrigerant to prevent it from leaking to the outside.

[0102] Referring to Figure 4, the battery cell assembly 100 according to this embodiment may include an end plate 500. The end plate 500 may be located on both open sides of the frame member 200 and may be formed to cover the seal assembly 400. The end plate 500 located on one open side of the frame member 200 may be a first end plate 510, and the end plate 500 located on the other open side of the frame member 200 may be a second end plate 550. The inlet 421 may be coupled to a first inlet hole 510H formed in the first end plate 510, and the outlet 461 may be coupled to a first outlet hole 550H formed in the second end plate 550. Such an end plate 500 can physically protect the battery cell stack 120 and other electrical components from external impacts.

[0103] Referring to Figures 11 to 13, the first subassembly 100a may include a first battery cell stack 120a and first busbar assemblies 301a and 302a. More specifically, the first busbar assemblies 301a and 302a can be positioned on the front and rear surfaces, respectively, of the first battery cell stack 120a. The first busbar assemblies 301a and 302a can be positioned in the direction in which the electrode leads 130 of the battery cells 110 contained in the first battery cell stack 120a protrude. A first flexible printed circuit board (FPCB) may also be provided, which is electrically connected to the first busbar assemblies 301a and 302a.

[0104] The first battery cell stack 120a may include a plurality of battery cells 110, at least one first cooling fin 210a located between the plurality of battery cells 110, and a first compression pad 250a provided on one side of the outermost battery cell 110.

[0105] The first cooling fin 210a can be positioned between multiple battery cells 110. For example, the first cooling fin 210a can be positioned between two or more battery cells 110. Specifically, one first cooling fin 210a and another adjacent first cooling fin 210a can be positioned with two or more battery cells 110 in between.

[0106] The first cooling fin 210a may include a first plate 211a that contacts one side of the battery cell 110. Here, the one side of the battery cell 110 may be one side of the battery body 113 (Figure 14) of the battery cell 110, and may be one side of the battery cell 110 that extends along the longitudinal direction (x-axis direction).

[0107] One surface of the first plate 211a can be in contact with one surface of a battery cell 110 that is facing the surface of the first plate 211a. The other surface of the first plate 211a can be in contact with one surface of another adjacent battery cell 110 that is facing the other surface of the first plate 211a. In this case, although not specifically shown, an adhesive member is interposed between the surface of the battery cell 110 and the first plate 211a, so that the battery cell 110 and the first plate 211a can be bonded and fixed together. For example, the adhesive member may be insulating tape.

[0108] The upper surface (in the z-axis direction) of the first plate 211a can contact the upper surface of the frame member 200, and the lower surface of the first plate 211a can contact the lower surface of the frame member 200. As a result, the first cooling fin 210a can be fixedly positioned within the frame member 200, and as a result, the battery cell 110 bonded to the first cooling fin 210a can also be fixedly positioned within the frame member 200.

[0109] If the size of the first plate 211a is larger than the size of the battery cell 110, the upper and lower parts of the battery cell 110 can be positioned at a certain distance from the upper and lower surfaces of the frame member 200. Specifically, if the height of the first plate 211a is longer than the height of the battery cell 110, the battery cell 110 can be bonded and fixed while being positioned in the center of the first plate 211a. In this case, the upper and lower parts of the battery cell 110 can be positioned at a certain distance from the upper and lower surfaces of the frame member 200. Here, the height of the battery cell 110 and the height of the first plate 211a refer to the length in the z-axis direction.

[0110] The first cooling fin 210a may further include a first plate 211a and a first projection 213a protruding from one end of the first plate 211a. For example, the first cooling fin 210a may be L-shaped. Specifically, referring to Figure 12, the first cooling fin 210a may include a first plate 211a having a surface corresponding to or larger than one side of the battery cell 110, and a first projection 213a protruding from one end of the first plate 211a so as to be parallel to the stacking direction (y-axis direction) of the first battery cell stack 120a.

[0111] The first protrusion 213a can contact at least one of the upper or lower surfaces of the frame member 200 in a region that protrudes perpendicular to the first plate 211a. Specifically, one surface of the first protrusion 213a can be positioned facing the upper or lower surface of the battery cell 110, and the other surface of the first protrusion 213a can contact the lower or upper surface of the frame member 200.

[0112] For example, one surface of the first protrusion 213a is positioned facing the lower surface of the battery cell 110, and the upper and lower surfaces of the battery cell 110 can be fixed to the first plate 211a at a certain height from the upper and lower surfaces of the frame member 200. That is, a certain space is provided between one surface of the first protrusion 213a and the lower surface of the battery cell 110, and between the upper surface of the frame member 200 and the upper surface of the battery cell 110, and a refrigerant, which will be described later, can move through this space. In this case, the distance between one surface of the first protrusion 213a and the lower surface of the battery cell 110 can correspond to the distance between the upper surface of the frame member 200 and the upper surface of the battery cell 110.

[0113] The other side of the first protrusion 213a can come into contact with the bottom of the frame member 200. Specifically, the other side of the first protrusion 213a can come into contact with and be bonded to the bottom of the frame member 200, thereby allowing the first cooling fin 210a to be fixedly positioned within the frame member 200.

[0114] However, the shape of the first cooling fin 210a is not limited to this drawing; it may be a flat plate shape, or any shape that can contact the battery cell 110 and fix the battery cell 110 in place.

[0115] The first cooling fin 210a may be made of metal. Specifically, the first cooling fin 210a may be made of a metal with high thermal conductivity. Therefore, the first cooling fin 210a can directly transfer the heat generated from the battery cell 110 by the charging and discharging of the battery. When heat is generated, the first cooling fin 210a, which is in contact with the side surface of the battery cell 110, is first cooled by the transfer of heat, and then the refrigerant, described later, comes into direct contact with the upper and lower parts of the battery cell 110 for secondary cooling. This makes it possible to directly cool the upper and lower regions of the battery cell, which were previously relatively difficult to cool, thereby improving cooling efficiency.

[0116] Furthermore, the second cooling fin 290a can be positioned between multiple battery cells 110. For example, the second cooling fin 290a can be positioned between two or more battery cells 110. Specifically, one second cooling fin 290a and another adjacent second cooling fin 290a can be positioned with two or more battery cells 110 in between. More specifically, the second cooling fin 290a differs from the first cooling fin 210a in that it does not include a separate protrusion, but its other features can be described in general the same way as the first cooling fin 210a.

[0117] The first compression pad 250a can be located between the battery cells 110 contained in the first battery cell stack 120a, or on the outermost edge of the first battery cell stack 120a. Such a first compression pad 250a can absorb the swelling of the battery cells 110 due to charging and discharging. Specifically, the first compression pad 250a can prevent the battery case 114 (Figure 14) of the battery cell 110 from cracking by pushing out the side of the frame member 200 as the battery cell 110 swells, thereby improving the safety of the battery cell assembly 100.

[0118] Referring to Figures 11 and 12, the first busbar assemblies 301a and 302b included in the first subassembly 100a may include a first front busbar assembly 301a covering the front of the first battery cell stack 120a and a first rear busbar assembly 302a covering the rear of the first battery cell stack 120a.

[0119] Here, the first front busbar assembly 301a may include a first front busbar frame 311a and a first busbar 331a mounted on the first front busbar frame 311a, respectively.

[0120] The first front busbar frame 311a is located on the front of the first battery cell stack 120a and may cover the front of the first battery cell stack 120a while also guiding the connection between the first battery cell stack 120a and external equipment.

[0121] A first busbar 331a may be mounted on the first front busbar frame 311a. Specifically, the inner surface of the first front busbar frame 311a can face the first battery cell stack 120a, and a first busbar 331a may be mounted on the outer surface of the first front busbar frame 311a.

[0122] The first front busbar frame 311a may include an electrically insulating material. The first front busbar frame 311a can restrict the first busbar 331a from contacting other parts of the battery cell 110 other than the portion joined to the electrode lead (not shown), thereby preventing electrical short circuits.

[0123] The first busbar 331a may be mounted on the outer surface of the first front busbar frame 311a and electrically connect the battery cells 110 contained in the first battery cell stack 120a, and electrically connect the first battery cell stack 120a to an external equipment circuit. The first busbar 331a is located on the first front busbar frame 311a, and such a first front busbar assembly 301a is covered by the seal assembly 400 and end plate 500 described later, so that it can be protected from external impacts and minimize the reduction in durability due to external moisture.

[0124] The first busbar 331a can be electrically connected to the first battery cell stack 120a via the electrode leads 130 of the battery cells 110. Specifically, the electrode leads 130 of the battery cells 110 pass through slits formed in the first front busbar frame 311a, then bend and can be connected to the first busbar 331a. The battery cells 110 contained in the first battery cell stack 120a are electrically connected in series or parallel by the first busbar 331a. There are no special restrictions on the connection method between the electrode leads 130 and the first busbar 331a; for example, welding can be used.

[0125] The first flexible printed circuit board 370a is mounted extending in the longitudinal direction of the battery cell 110 and is configured to sense the battery cell 110. That is, as shown in Figures 11 and 12, the first flexible printed circuit board 370a is located on the upper surface of the first battery cell stack 120a and senses voltage data and thermal data of the battery cell 110. In particular, the first flexible printed circuit board 370a is bent from one end toward the first busbar frame 310a and can be electrically connected to the first busbar 331a. This allows it to sense the voltage data of each battery cell 110 and transmit it to the outside.

[0126] Here, the first rear busbar assembly 302a may include the first rear busbar frame 312a and the first busbar 331a which is mounted on the first rear busbar frame 312a, respectively. The description of the first rear busbar assembly 302a can be described in much the same way as the description of the first front busbar assembly 301a above, and only the differences will be described later.

[0127] More specifically, in the first rear busbar assembly 302a, the first interbusbar 340a can be located on both sides of the first rear busbar frame 312a, respectively. Here, the first interbusbar 340a may be electrically connected to the first busbar 331a mounted on the first rear busbar frame 312a. More specifically, the first interbusbar 340a may include a first positive interbusbar 341a and a first negative interbusbar 345a having opposite polarities. Also, as mentioned above, the first positive interbusbar 341a and the first negative interbusbar 345a can be electrically connected to terminal busbars 353a and 352b included in terminal busbar assemblies 350a and 350b located outside the frame member 200.

[0128] Furthermore, the first rear busbar assembly 302a may be located on the rear surface of the first battery cell stack 120a, covering the rear surface of the first battery cell stack 120a and guiding the connection between the first battery cell stack 120a and external equipment. In particular, the first rear busbar assembly 302a is located inside the frame member 200, protecting the electrical connection structure between the first interbusbar 340a and the terminal busbars 353a and 352b from external shocks and the like.

[0129] Referring to Figures 8, 9, and 11, in the battery cell assembly 100 according to this embodiment, the first subassembly 100a and the second subassembly 100b are arranged such that the first rear busbar assembly 302a of the first subassembly 100a and the second rear busbar assembly 302b of the second subassembly 100b face each other. In other words, the first rear busbar assembly 302a of the first subassembly 100a and the second rear busbar assembly 302b of the second subassembly 100b can be located in the center of the battery cell assembly 100.

[0130] As a result, the first rear busbar assembly 302a and the second rear busbar assembly 302b are located in the center of the battery cell assembly 100, and when multiple battery cell assemblies 100 are arranged along the width direction of the battery cell assembly 100, the electrical connection structures between the first interbusbar 340a and terminal busbars 353a and 352b, and between the second interbusbar 340b and terminal busbars 352a and 353b are located between adjacent battery cell assemblies 100.

[0131] In other words, in a structure in which multiple battery cell assemblies 100 are arranged, the electrical connection structure between the first interbus bar 340a and the terminal bus bars 353a and 352b, and the electrical connection structure between the second interbus bar 340b and the terminal bus bars 352a and 353b can be more stably protected from external shocks and the like.

[0132] Referring to Figure 9, the battery cell assembly 100 according to this embodiment may be provided with a side plate 270 that covers both sides of the first subassembly 100a and the second subassembly 100b. Here, the length of the side plate 270 can correspond to the sum of the lengths of the first subassembly 100a and the second subassembly 100b. However, the shape of the side plate 270 is not limited to this, and multiple side plates 270 can each cover both sides of the first subassembly 100a and the second subassembly 100b.

[0133] The side plate 270 may be a plate extending along the length of the battery cell 110. For example, the side plate 270 may be made of a rigid metal.

[0134] The side plate 270 can be positioned facing the outermost battery cell 110 among the battery cells 110 included in the first subassembly 100a and the outermost battery cell 110 among the battery cells 110 included in the second subassembly 100b.

[0135] As a result, in the battery cell assembly 100 according to this embodiment, the side plate 270 can protect the outermost battery cells 110 and compression pads 250a of the first subassembly 100a and the second subassembly 100b when they are inserted and mounted onto the frame member 200 with the insulating plate 700 in between.

[0136] Furthermore, the battery cell assembly 100 in this embodiment is a twin model having a first battery cell stack 120a and a second battery cell stack 120b, and because the battery cell stack 120 is longer than a typical battery cell stack, it may not be easy to insert and assemble it into the frame member 200. In this case, as shown in Figures 8 and 9, the side plate 270 can guide the insertion of the battery cell stack 120 into the frame member 200, allowing the battery cell assembly to be easily assembled without damaging the battery cells 110 and / or compression pads 250a, 250b.

[0137] Referring to Figures 9 and 10, a side recess 270a may be formed in the center of the side plate 270 included in the battery cell assembly 100 of this embodiment. Here, the side recess 270a may be a portion formed by recessing from the top of the side plate 270 toward the center. Here, the interbus bars 340a and 340b of the first subassembly 100a and the second subassembly 100b of this embodiment can be exposed to the outside of the side plate 270 through the side recess 270a.

[0138] As a result, the side plate 270 can protect the internal components of the battery cell assembly 100 and facilitate the assembly of the battery cell assembly 100, as described above, while also stably assisting in the electrical connections between the inside and outside of the battery cell assembly 100.

[0139] The following describes in detail the structure for circulating a refrigerant inside the battery cell assembly according to this embodiment.

[0140] Referring again to Figures 4, 9, and 11, the battery cell assembly 100 according to this embodiment includes an inlet 421 and an outlet 461 for circulating a refrigerant inside the frame member 200. The refrigerant flows into the frame member 200 through the inlet 421 and is then discharged outside the battery cell assembly 100 through the outlet 461.

[0141] The refrigerant can receive heat transfer generated from the first battery cell stack 120a, the second battery cell stack 120b, the first busbar assemblies 301a, 302a, the second busbar assemblies 301b, 302b, and other electrical components housed inside the frame member 200, while in direct contact with them.

[0142] The refrigerant may be a fluid. However, since the refrigerant comes into direct contact with the first battery cell stack 120a, the second battery cell stack 120b, the first busbar assemblies 301a, 302a, the second busbar assemblies 301b, 302b, and other electrical components within the battery cell assembly 100, the refrigerant needs to be electrically insulated. Therefore, the refrigerant may be an insulating material. For example, the refrigerant may be an insulating oil.

[0143] In other words, in this embodiment, the refrigerant directly contacts the first battery cell stack 120a, the second battery cell stack 120b, the first busbar assemblies 301a, 302a, the second busbar assemblies 301b, 302b, and other electrical components that generate heat within the battery cell assembly 100, and receives heat transfer, thereby directly cooling them. Therefore, compared to conventional battery modules 1 (see Figure 3) which indirectly cool the battery module 1 using a heat sink 6 or the like, the battery cell assembly 100 according to this embodiment can improve cooling efficiency through direct cooling, thereby extending the battery life.

[0144] In this embodiment, an insulating plate 700 is placed between the first battery cell stack 120a and the second battery cell stack 120b, and an opening 700H is formed in the insulating plate 700 through which the refrigerant passes. For example, the opening 700H can be formed in the center of the insulating plate 700, and more specifically, the opening 700H can be formed in a rectangular shape with its top and bottom edges extending from both sides. That is, the opening 700H can be formed to extend along the direction in which the battery cells 110 are stacked.

[0145] The insulating plate 700 includes a first insulating projection 700B1 located at the top and a second insulating projection 700B2 located at the bottom, and the first insulating projection 700B1 and the second insulating projection 700B2 can be stably connected in a manner that interlocks with the first rear busbar assembly 302a and the second rear busbar assembly 302b, respectively.

[0146] The insulating plate 700 may include a material that has electrical insulating properties. For example, the insulating plate 700 may be a plastic injection molded product.

[0147] More specifically, with respect to the insulating plate 700, the inlet 421 and the outlet 461 can be located on opposite sides of each other. The first battery cell stack 120a can be located between the inlet 421 and the insulating plate 700, and the second battery cell stack 120b can be located between the outlet 461 and the insulating plate 700. The refrigerant flowing in through the inlet 421 can pass through the first battery cell stack 120a, the opening 700H of the insulating plate 700, and the second battery cell stack 120b in sequence, and be discharged through the outlet 461.

[0148] Since the first battery cell stack 120a and the second battery cell stack 120b are both contained within a single frame member 200, there is a risk of short circuits occurring due to contact between the first battery cell stack 120a and the second battery cell stack 120b, or between the first rear busbar assembly 302a located on the rear surface of the first battery cell stack 120a and the second rear busbar assembly 302b located on the rear surface of the second battery cell stack 120b.

[0149] Furthermore, as described above, the battery cell assembly 100 according to this embodiment includes a first battery cell stack 120a and a second battery cell stack 120b, and has a form that extends along the longitudinal direction. When the refrigerant circulates inside the frame member 200, there is a possibility that a section may occur between the first battery cell stack 120a and the second battery cell stack 120b where the flow of the refrigerant stagnates.

[0150] In this embodiment, an insulating plate 700 having electrical insulation properties was placed between the first battery cell stack 120a and the second battery cell stack 120b. The insulating plate 700 was used to ensure electrical insulation and creepage distance between the first battery cell stack 120a and the second battery cell stack 120b, or between the first rear busbar assembly 302a located on the rear surface of the first battery cell stack 120a and the second rear busbar assembly 302b located on the rear surface of the second battery cell stack 120b.

[0151] Furthermore, by designing the insulating plate 700 such that an opening 700H through which the refrigerant passes is formed in the center of the insulating plate 700, stagnation of the refrigerant flow in the space between the first battery cell stack 120a and the second battery cell stack 120b is prevented. In other words, the aim was to improve cooling performance by ensuring the flow of the refrigerant.

[0152] Referring to Figures 4 and 9, as described above, the battery cell assembly 100 may include a first seal assembly 410 and a second seal assembly 450 that cover the open sides of the frame member 200, respectively. The inlet 421 can be coupled to a second inlet hole 410H formed in the first seal assembly 410, and the outlet 461 can be coupled to a second outlet hole 450H formed in the second seal assembly 450.

[0153] As described above, the battery cell 110 according to this embodiment is a pouch-type battery cell and may include electrode leads 130 protruding in both directions. The direction between the electrode leads 130 protruding in both directions can be the longitudinal direction of the battery cell 110. The direction parallel to the x-axis corresponds to the longitudinal direction of the battery cell 110. Along this longitudinal direction, the first seal assembly 410, the first battery cell stack 120a, the insulating plate 700, the second battery cell stack 120b, and the second seal assembly 450 can be positioned in order. That is, the refrigerant that flows in through the inlet 421 formed in the first seal assembly 410 can pass through the first battery cell stack 120a, the opening 700H of the insulating plate 700, and the second battery cell stack 120b in order, and be discharged through the outlet 461 formed in the second seal assembly 450.

[0154] In the battery cell assembly 100 according to this embodiment, the first front busbar assembly 301a, which is electrically connected to the first battery cell stack 120a, and the second front busbar assembly 301b, which is electrically connected to the second battery cell stack 120b, can be located on one open side of the frame member 200. Here, the first seal assembly 410 can be mounted over the first front busbar assembly 301a, and the second seal assembly 450 can be mounted over the second front busbar assembly 301b. More specifically, the first seal assembly 410 can cover the first front busbar assembly 301a located on one side of the first battery cell stack 120a, and the second seal assembly 450 can cover the second front busbar assembly 301b located on one side of the second battery cell stack 120b.

[0155] Furthermore, unlike in Figure 4, the inlet 421 can be located below the center, relative to the height of the battery cell stack 120. The inlet 421 can be located near the lower end of the first seal assembly 410. Specifically, the inlet 421 can be located below the center, relative to the height of the first seal assembly 410. Here, the height of the battery cell stack 120 and the first seal assembly 410 refers to the length in the z-axis direction in the drawing.

[0156] Combining the positions of the inlet 421 and outlet 461 described earlier, the inlet 421 can be located below the center relative to the height of the battery cell stack 120, and the outlet 461 can be located above the center relative to the height of the battery cell stack 120. In other words, the inlet 421 can be located near the lower end of the first seal assembly 410, and the outlet 461 can be located near the upper end of the second seal assembly 450.

[0157] If the inlet 421 is located above the center relative to the height of the battery cell stack 120, the refrigerant will flow into the battery cell assembly 100 from a higher position, potentially causing bubbles to form inside the refrigerant. Such bubbles can hinder the cooling effect.

[0158] Furthermore, if the outlet 461 is located below the center relative to the height of the battery cell stack 120, the refrigerant that flows into the battery cell assembly 100 will fill up to the height of the outlet 461 and then escape to the outside. As a result, the inside of the battery cell assembly 100 will not be filled with a sufficient amount of refrigerant, and the cooling performance will decrease.

[0159] Therefore, in order to prevent foaming from occurring in the incoming refrigerant and to ensure that the inside of the battery cell assembly 100 is completely filled with refrigerant, it is preferable that the inlet 421 is located below the center with respect to the height of the battery cell stack 120, and the outlet 461 is located above the center with respect to the height of the battery cell stack 120.

[0160] In this embodiment, terms indicating directions such as front, back, left, right, up, and down were used. However, these terms are for convenience of explanation and may differ depending on the position of the object being examined, the observer's position, etc.

[0161] One or more battery cell assemblies according to the above-described embodiment can be mounted together with various control and protection systems such as a Battery Management System (BMS), Battery Disconnect Unit (BDU), and cooling system to form a battery pack.

[0162] The aforementioned battery cell assemblies and battery packs can be applied to a variety of devices. Specifically, they can be applied to means of transportation such as electric bicycles, electric vehicles, and hybrids, as well as ESS (Energy Storage Systems), but are not limited to these, and can be applied to various devices that can use secondary batteries.

[0163] Although preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto. Various modifications and improvements by those skilled in the art, utilizing the basic concepts of the present invention as defined in the following claims, also fall within the scope of the present invention. [Explanation of Symbols]

[0164] 100: Battery cell assembly 100a: First subassembly 100b: Second subassembly 110: Battery cell 120: Battery cell stack 200: Frame component 200H: Frame Hole 205: Frame indentation 301a: First front busbar assembly 302a: First rear busbar assembly 301b: Second front busbar assembly 302b: Second rear busbar assembly 350a: Terminal 1 Busbar Assembly 350b: Terminal 2 Bus Bar Assembly 340a: First Interbus Bar 340b: Second Interchange Bus Bar 400: Seal Assembly 700: Insulating plate 700H: Opening

Claims

1. A subassembly including a battery cell stack formed by stacking multiple battery cells; A frame member that houses the subassembly; and An interbus bar included in the subassembly that is electrically connected to the battery cell; A terminal member including one end on which a screw thread is formed; A frame hole formed on at least one side surface of the frame member; and Includes a terminal busbar assembly that covers the frame hole and connects to the terminal member, A frame recess is formed on at least one side surface of the frame member, which is recessed from the outer surface of the frame member toward the interior of the frame member. The frame hole is formed in the recessed portion of the frame. The space between the frame recess and the terminal busbar assembly is filled with a sealing member. A battery cell assembly in which an interbus bar hole is formed on the surface of the interbus bar facing one side of the frame member, the frame hole and the interbus bar hole are arranged to overlap each other, and one end of the terminal member is inserted into the interbus bar hole through the frame hole and coupled to the interbus bar hole.

2. The aforementioned terminal busbar assembly is A terminal busbar electrically connected to the terminal member, and The terminal busbar includes a terminal busbar frame made of an electrically insulating material that encloses at least a portion of the terminal busbar, One end of the terminal busbar is exposed to the outside of the terminal busbar frame, and the other end of the terminal busbar has a terminal busbar hole formed therein. The battery cell assembly according to claim 1, wherein one end of the terminal member passes through the terminal busbar hole and is coupled to the interbusbar hole.

3. The terminal member includes the other end on which a screw thread is formed, The battery cell assembly according to claim 2, wherein the other end of the terminal member passes through the terminal busbar hole and is coupled with a nut.

4. The battery cell assembly according to claim 3, wherein a gasket is located between a nut coupled to the other end of the terminal member and the terminal busbar hole.

5. The battery cell assembly according to claim 1, wherein the size of the frame recess and the terminal busbar assembly are the same as each other.

6. The subassembly includes a first subassembly comprising a first battery cell stack, and a second subassembly comprising a second battery cell stack. The interbus bar includes a pair of first interbus bars electrically connected to the battery cell included in the first subassembly, and a pair of second interbus bars electrically connected to the battery cell included in the second subassembly. The terminal members consist of multiple units, and are electrically connected to the pair of first interbusbars and the pair of second interbusbars, respectively. The battery cell assembly according to claim 1, wherein the first interbus bar and the second interbus bar are respectively located in the space between the first battery cell stack and the second battery cell stack.

7. The frame holes include a pair of first frame holes located on one side of the frame member, and a pair of second frame holes located on the other side of the frame member. The terminal busbar assembly includes a first terminal busbar assembly covering the pair of first frame holes, and a second terminal busbar assembly covering the pair of second frame holes. The first terminal busbar assembly is electrically connected to one of the pair of first interbusbars and one of the pair of second interbusbars. The battery cell assembly according to claim 6, wherein the second terminal busbar assembly is electrically connected to the other of the pair of first interbusbars and the other of the pair of second interbusbars.

8. The frame member includes an inlet and an outlet for circulating a refrigerant, The battery cell assembly according to claim 1, wherein the refrigerant flows into the interior of the frame member through the inlet and is discharged through the outlet.

9. The subassembly includes a first subassembly comprising a first battery cell stack, and a second subassembly comprising a second battery cell stack. An insulating plate is placed between the first subassembly and the second subassembly. The battery cell assembly according to claim 8, wherein the insulating plate has an opening through which the refrigerant passes.

10. With respect to the insulating plate, the inlet and the outlet are located on opposite sides of each other. The first subassembly is located between the inlet and the insulating plate. The battery cell assembly according to claim 9, wherein the second subassembly is located between the outlet and the insulating plate.

11. The battery cell assembly according to claim 10, wherein the refrigerant that flows in through the inlet passes in order through the first subassembly, the opening of the insulating plate, and the second subassembly, and is discharged through the outlet.

12. The system further includes a first seal assembly and a second seal assembly that cover the open sides of the frame member, respectively. The battery cell assembly according to claim 9, wherein the inlet is coupled to the first seal assembly and the outlet is coupled to the second seal assembly.

13. The aforementioned battery cell includes electrode leads protruding in both directions. The battery cell assembly according to claim 12, wherein, with the direction between the electrode leads being the longitudinal direction, the first seal assembly, the first sub-assembly, the insulating plate, the second sub-assembly, and the second seal assembly are positioned in order along the longitudinal direction.

14. The refrigerant is insulating oil, The battery cell assembly according to claim 8, wherein the refrigerant is in direct contact with the battery cell stack housed inside the frame member.

15. A battery pack comprising a battery cell assembly according to any one of claims 1 to 14.

Images