Battery assembly and battery pack containing the 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 fixed frame covering at least a portion of the battery cell stack, an outer frame housing the battery cell stack and the fixed frame, and an inlet and an outlet for circulating a coolant inside the outer frame.

Description

Technical Field

[0001] [Cross - Reference to Related Applications] This application claims the benefit of priority based on Korean Patent Application No. 10 - 2024 - 0021641 filed on February 15, 2024 and Korean Patent Application No. 10 - 2025 - 0015066 filed on February 6, 2025, and all the contents disclosed in the literature of the Korean patent applications are included as part of this specification.

[0002] The present invention relates to a battery assembly and a battery pack including the same, and more specifically, to a battery assembly and a battery pack including the same, in which the cooling performance is improved, the fixing force of battery cells is strengthened, and the vibration and impact performance of the battery assembly are improved.

Background Art

[0003] Due to the increasing technological development and demand for mobile devices, the demand for secondary batteries as an energy source has been rapidly increasing. Accordingly, much research has been conducted on secondary batteries that can meet various requirements.

[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] Recently, with the utilization of secondary batteries as an energy storage source, the need for a large - capacity secondary battery structure has increased, and the demand for a battery pack with a medium - to - large - sized module structure in which a number of battery assemblies in which a large number of secondary batteries are connected in series / parallel are assembled has been increasing.

[0006] On the other hand, when configuring a battery pack by connecting multiple battery cells in series or parallel, it is common practice to first configure a battery assembly consisting of at least one battery cell, and then use that at least one battery assembly to add other components and configure the battery pack.

[0007] The battery cells that make up such medium- and large-sized battery assemblies 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 can accumulate in a confined space, potentially causing the temperature to rise rapidly and drastically. In other words, while high output can be obtained in battery assemblies with many battery cells stacked on top of each other and in battery packs equipped with such assemblies, it is not easy to remove the heat generated by the battery cells during charging and discharging. If the heat from the battery cells is not properly dissipated, the battery cells will deteriorate more quickly, shortening their lifespan and increasing the risk of explosion or fire.

[0008] Furthermore, battery assemblies included in vehicle battery packs are often exposed to direct sunlight and subjected to high-temperature conditions such as summer or desert regions. Also, because numerous battery assemblies are densely arranged to increase the vehicle's driving range, flames or heat generated in one battery assembly can easily spread to neighboring battery assemblies, potentially leading to the ignition or explosion of the battery pack itself.

[0009] Figure 1 is a disassembled perspective view of a conventional battery pack.

[0010] Referring to Figure 1, a conventional battery pack 10 includes a lower pack frame 11 on which multiple battery assemblies 1 are mounted, an upper pack frame 12 located above the battery assemblies 1, and an internal beam 13 that demarcates the positions in the battery pack 10 where the battery assemblies 1 are mounted.

[0011] Thus, when battery assemblies 1 are installed inside a battery pack 10, the internal beams 13 that partition the battery assemblies 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 presents a problem. In addition, the weight of the battery pack 10 limits the number of battery packs 10 that can be installed in a device. Consequently, it is necessary to reduce the weight of the battery pack 10 while simultaneously reducing its energy density, so that a larger number of battery assemblies 1 can be installed inside the battery pack 10.

[0012] Figure 2 is a cross-sectional view showing the battery assembly in Figure 1.

[0013] Referring to Figure 2, a conventional battery assembly 1 includes a battery cell stack 3 containing battery cells 2 stacked in a predetermined direction, and an outer 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 outer frame 4. In this case, a heat sink 6 can be provided in contact with the bottom of the outer frame 4, which is located in the -z axis direction in Figure 3, to cool the heat generated in the battery cell stack 3.

[0014] However, since the heatsink 6 does not directly contact the battery cell stack 3 to transfer heat, it has the disadvantage of not being very efficient at cooling, and there is a need for a more effective way to cool the battery assembly 1. [Overview of the Initiative] [Problems that the invention aims to solve]

[0015] The problem that this invention aims to solve is to provide a battery assembly and a battery pack including the same, in which the vibration and shock performance of the battery assembly is improved by strengthening the fixing force of the battery cells.

[0016] However, the problems that the embodiments of the present invention aim to solve are not limited to those described above, and can be broadly extended 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 fixed frame covering at least a portion of the battery cell stack, an outer frame housing the battery cell stack and the fixed frame, and an inlet and an outlet for circulating a coolant inside the outer frame.

[0018] The battery cell stack may include a first battery cell stack and a second battery cell stack arranged along the longitudinal direction in which the electrode leads protrude from the battery cells. The first battery cell stack and the second battery cell stack can be fixed to the fixed frame.

[0019] The fixing frame may include side portions that cover both sides of the battery cell stack, and the two side portions of the fixing frame can make surface contact with each of the outermost battery cells in the battery cell stack.

[0020] The battery cell stack may include a first battery cell stack and a second battery cell stack. It may also include a first busbar frame assembly provided on one side of the first battery cell stack and a second busbar frame assembly provided on one side of the second battery cell stack.

[0021] The battery assembly may further include an insulating plate that is fastened between the first busbar frame assembly and the second busbar frame assembly to at least one of the first busbar frame assembly or the second busbar frame assembly.

[0022] The insulating plate can include a flow path hole through which the refrigerant can move. The refrigerant can move between the first battery cell stack and the second battery cell stack through the flow path hole.

[0023] The insulating plate and the bus bar frame assembly can be bolted together.

[0024] Based on the insulating plate, the inlet and the outlet can be located on opposite sides of each other.

[0025] The first battery cell stack can be located between the inlet and the insulating plate, and the second battery cell stack can be located between the outlet and the insulating plate.

[0026] The refrigerant flowing in through the inlet can sequentially pass through the first battery cell stack, the flow path hole included in the insulating plate, and the second battery cell stack, and can be discharged through the outlet.

[0027] The battery assembly can further include a cooling spacer located at at least one location among the plurality of battery cells. The cooling spacer includes a plurality of cooling holes opened along the length direction, and the refrigerant can move to the plurality of cooling holes.

[0028] The fixed frame can include a lower surface portion that covers the lower surface of the battery cell stack. A first adhesive member can be located between the lower surface of the battery cell stack and the lower surface portion of the fixed frame. The first adhesive member can be adhered to each of the lower surface of the battery cell stack and the lower surface portion of the fixed frame.

[0029] The fixing frame may include side portions that cover both sides of the battery cell stack. A second adhesive member may be positioned at least one location between the side of the battery cell stack and the side portion of the fixing frame. The second adhesive member may be bonded to the side of the battery cell stack and the side portion of the fixing frame, respectively.

[0030] The battery assembly may further include cooling fins located at least one location between the battery cells. The mounting frame may include a bottom portion that covers the bottom surface of the battery cell stack, and the cooling fins may be fixed between the bottom portion of the mounting frame and the top portion of the outer frame.

[0031] The cooling fin may include a main part located between the battery cells, a first support part extending perpendicularly to one surface of the main part at the upper end of the main part, and a second support part extending perpendicularly to one surface of the main part at the lower end of the main part.

[0032] The first support part can contact the ceiling portion of the outer frame, and the second support part can contact the lower surface portion of the fixed frame.

[0033] According to yet another embodiment of the present invention, a battery pack including the battery assembly is provided. [Effects of the Invention]

[0034] According to embodiments of the present invention, the energy density of the battery pack can be improved by electrically connecting each battery assembly.

[0035] Furthermore, by more effectively cooling the top and bottom surfaces of the battery cells, cooling efficiency can be improved, ensuring the safety of the battery assembly and battery pack.

[0036] The effects of the present invention are not limited to those described above, and other effects not mentioned will be clearly understood by those skilled in the art from the claims. [Brief explanation of the drawing]

[0037] [Figure 1] This is a disassembled perspective view of a conventional battery pack. [Figure 2] Figure 1 is a cross-sectional view showing the battery assembly. [Figure 3] This is a perspective view showing a battery assembly according to one embodiment of the present invention. [Figure 4] This is a perspective view showing a configuration included in a battery assembly according to one embodiment of the present invention, including a first battery cell stack and a first busbar frame assembly. [Figure 5] This is an exploded perspective view showing the first battery cell stack, the first busbar frame assembly, and the flexible printed circuit board. [Figure 6] Figure 3 is an exploded perspective view excluding the fixed frame and outer frame. [Figure 7] Figure 6 is an exploded perspective view with a fixed frame added. [Figure 8] This is a perspective view showing the lower part of Figure 7 from a different angle. [Figure 9] Figure 7 is a diagram showing how it is inserted into the outer frame. [Figure 10] This is a perspective view showing the location of the refrigerant within the battery assembly. [Figure 11] This is a top view of a battery assembly according to one embodiment of the present invention, in which the upper end of the outer frame is omitted. [Figure 12] This is an exploded perspective view showing the insulating plates between stacks of battery cells. [Figure 13] This is a perspective view showing an insulating plate according to one embodiment of the present invention. [Figure 14] This is a plan view of a cooling spacer according to one embodiment of the present invention. [Figure 15] This is a perspective view of a cooling spacer according to one embodiment of the present invention. [Figure 16] This is a cross-sectional view showing a section cut along the cutting line B-B' in Figure 3. [Figure 17] This is a perspective view showing a cooling fin according to one embodiment of the present invention. [Figure 18] This is a cross-sectional view of a battery assembly according to another embodiment of the present invention. [Figure 19] This is an exploded perspective view of a battery pack according to one embodiment of the present invention. [Modes for carrying out the invention]

[0038] Hereinafter, various embodiments of the present invention will be described in detail with reference to the attached drawings, so that they can be easily implemented by a person with ordinary skill in the art to which the present invention pertains. The present invention can be realized in a variety of different forms and is not limited to the embodiments described herein.

[0039] To clearly explain the present invention, descriptive parts that are unnecessary have been omitted, and the same or similar reference numerals are used throughout the specification for identical or similar components.

[0040] Furthermore, the dimensions and thicknesses of each component shown in the drawings are arbitrary for illustrative purposes, and the present invention is not necessarily limited to those shown. The thicknesses are enlarged in the drawings to clearly represent various layers and regions. Additionally, the thicknesses of some layers and regions are exaggerated in the drawings for illustrative purposes.

[0041] Furthermore, when we say that a layer, membrane, region, plate, or other part is "on top" of another part, this includes not only the case where it is "directly above" the other part, but also the case where the other part is in between. Conversely, when we say that one part is "directly above" another part, it means that there is no other part in between. Also, being "on top" of a reference part means being located above or below the reference part, and does not necessarily mean being located "up" in the opposite direction of gravity.

[0042] Furthermore, when a specification states that a certain part "includes" a certain component, unless otherwise specified, this means that it can further encompass other components rather than excluding them.

[0043] Furthermore, throughout the specification, "on a plane" means when the subject is viewed from above, and "on a cross-section" means when the subject is viewed from the side of a cross-section obtained by cutting the subject perpendicularly.

[0044] Figure 3 is a perspective view showing a battery assembly 100 according to one embodiment of the present invention. Figure 4 is a perspective view showing a configuration included in the battery assembly 100 according to one embodiment of the present invention, including a first battery cell stack 120a, a first busbar frame assembly 180, and a flexible printed circuit board 330. Figure 5 is an exploded perspective view showing the first battery cell stack 120a, the first busbar frame assembly 180, and the flexible printed circuit board 330. Figure 6 is an exploded perspective view excluding the outer frame 140 of Figure 3 and the fixed frame 130 of Figure 8. Figure 7 is an exploded perspective view with the fixed frame 130 added to Figure 6. Figure 8 is a perspective view shown at a different angle so that the lower part of Figure 7 is visible. Figure 9 is a drawing showing the configuration of Figure 7 being inserted into the outer frame 140. Figure 10 is a perspective view showing the location of the refrigerant inside the battery assembly 100. Figure 11 is a top view of the battery assembly 100 according to one embodiment of the present invention, with the upper end of the outer frame 140 omitted.

[0045] Referring to Figures 3 to 11, a battery assembly 100 according to one embodiment of the present invention includes a battery cell stack 120 in which a plurality of battery cells 110 are stacked, a fixed frame 130 that covers at least a portion of the battery cell stack 120, an outer frame 140 that houses the battery cell stack 120 and the fixed frame 130, and an inlet 160 and an outlet 170 for circulating a coolant inside the outer frame 140.

[0046] First, the battery cell 110 can be a pouch-type battery cell. 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 heat-sealing the pouch case. In this case, the battery cell 110 can be formed in a rectangular sheet-type structure.

[0047] Such battery cells 110 can be composed of multiple units, and multiple battery cells 110 can be stacked so as to be electrically connected to each other to form a battery cell stack 120. In particular, as shown in Figure 4, multiple battery cells 110 can be stacked along a direction parallel to the y-axis direction. The direction in which multiple battery cells 110 are stacked as described above can be defined as the width direction of the battery cell stack 120.

[0048] The fixed frame 130 can be positioned while covering at least one side of the battery cell stack 120. The fixed frame 130 can be positioned while covering the lower part of the battery cell stack 120, and more specifically, the fixed frame 130 can be positioned while covering part of the lower surface and side of the battery cell stack 120.

[0049] The outer frame 140 may be for protecting the battery cell stack 120 and the electrical components connected thereto from external physical shocks. The outer frame 140 can house the battery cell stack 120 and the electrical components connected thereto within its internal space.

[0050] The structure of the outer frame 140 can be diverse. According to this embodiment, the structure of the outer frame 140 can be a monoframe structure. Here, the monoframe can be in the form of a metal plate material in which the top surface, bottom surface and both sides are integrated. The monoframe can be manufactured by extrusion molding.

[0051] However, the structure of the outer frame 140 is not limited to this. As another example, the outer frame 140 can be a structure in which a U-shaped frame and an upper plate are joined together. In this case, the U-shaped frame can be formed by joining or integrating the bottom surface and both sides of the outer frame 140. At this time, each frame or plate constituting the U-shaped frame can be manufactured by press molding. Furthermore, the structure of the outer frame 140 may be provided as an L-shaped frame structure in addition to a monoframe or U-shaped frame, and may be provided in a variety of structures not described in the examples above.

[0052] The outer frame 140 can be provided in a configuration in which the front and rear surfaces are open along the longitudinal direction (x-axis direction). Here, the longitudinal direction can be the direction in which the electrode leads 111 protrude from the battery cell 110, as will be described later. In this case, the front and rear surfaces of the battery cell stack 120 do not need to be shielded by the outer frame 140. The front and rear surfaces of the battery cell stack 120 may be shielded by busbar frame assemblies 180, 190, etc., thereby protecting the front and rear surfaces of the battery cell stack 120 from external physical shocks, etc.

[0053] Referring particularly to Figures 10 and 11, in the battery assembly 100 according to this embodiment, the refrigerant can flow into the outer frame 140 through the inlet 160 and then be discharged to the outside of the battery assembly 100 through the outlet 170. At this time, the refrigerant can be a fluid. However, since the refrigerant comes into direct contact with the battery cell stack 120, other electrical components, and the busbar frame assemblies 180, 190, etc., within the battery assembly 100, it needs to be electrically insulated. Therefore, the refrigerant can be an insulating material. As an example, the refrigerant can be insulating oil.

[0054] In a first direction d1 and a second direction d2 that are parallel to and opposite to the direction in which the battery cells 110 are stacked, the inlet 160 can 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. The outlet 170 can 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 110 are stacked. In other words, it is preferable that the inlet 160 and the outlet 170 are located on opposite sides of each other with respect to the direction in which the battery cells 110 are stacked. When the inlet 160 and the outlet 170 are arranged in this way, the coolant can flow throughout the entire space inside the outer frame 140 and cool all the battery cells 110 evenly. If both the inlet 160 and the outlet 170 are located in the center of the battery cell stack 120 in the direction in which the battery cells 110 are stacked, the coolant will flow only to the central part, which has the least flow resistance, and therefore the battery cells 110 located on the outer part of the battery cell stack 120 will not receive sufficient coolant flow. Ultimately, this leads to a cooling imbalance inside the battery assembly 100. Similarly, if both the inlet 160 and the outlet 170 are located biased towards either the first direction d1 or the second direction d2, the coolant will flow only to some of the battery cells 110 on the outer part adjacent to the biased direction, resulting in a cooling imbalance inside the battery assembly 100. Therefore, in order to guide the coolant to flow evenly to all the battery cells 110 inside the battery assembly 100, as described above, it is preferable that the inlet 160 and the outlet 170 are located on opposite sides of each other with respect to the direction in which the battery cells 110 are stacked.

[0055] The end plates 300 can be located on the open first side (x-axis direction) and second side (-x-axis direction) of the outer frame 140. The end plate 300 located on the open first side of the outer frame 140 can be the first end plate 310, and the end plate 300 located on the open second side of the outer frame 140 can be the second end plate 320. Such end plates 300 can physically protect the battery cell stack 120 and other electrical components from external impacts.

[0056] The inlet 160 may be a hole including a projection (not shown) that protrudes in the opposite direction from the area where the outer frame 140 is positioned. The projection may be located through an inlet opening (not shown) formed in the first end plate 310.

[0057] The outlet 170 may be a hole including a projection (not shown) that protrudes in the opposite direction from the area where the outer frame 140 is located. The projection may be located through an outlet opening (not shown) formed in the second end plate 320.

[0058] A battery cell stack 120 according to one embodiment of the present invention includes a first battery cell stack 120a and a second battery cell stack 120b arranged along the longitudinal direction in which the electrode leads 111 protrude from the battery cell 110. The first battery cell stack 120a and the second battery cell stack 120b are fixed to a fixed frame 130.

[0059] Specifically, the battery assembly 100 of this embodiment can be one in which one end and the other end of each battery cell stack 120 that constitutes two conventional battery assemblies 100 are electrically connected. In other words, the first battery cell stack 120a and the second battery cell stack 120b can be electrically coupled.

[0060] The fixed frame 130 is made of a rigid material and serves to protect the battery cell stack 120 from external physical impacts and to firmly fix and support them within the outer frame 140.

[0061] Referring again to Figures 7 and 8, a fixed frame 130 according to one embodiment of the present invention may include side portions 131 that cover both sides of the battery cell stack 120 and a bottom portion 132 that covers the bottom of the battery cell stack 120. This can correspond to one exemplary structure of the fixed frame 130. Both side portions 131 of the fixed frame 130 can make surface contact with each of the outermost battery cells 110 in the battery cell stack 120.

[0062] In other words, by eliminating the gap between the battery cell stack 120 and the fixed frame 130, the fixing force of the battery cell stack 120 can be strengthened. This protects the battery cells 110 from external physical shocks and improves the vibration and shock performance of the battery assembly 100.

[0063] Referring again to Figures 4-8, 10, and 11, a battery assembly 100 according to one embodiment of the present invention may further include a first busbar frame assembly 180 provided on one side of the first battery cell stack 120a and a second busbar frame assembly 190 provided on one side of the second battery cell stack 120b.

[0064] The busbar frame assemblies 180 and 190 can be positioned on the open first (x-axis direction) and second (-x-axis direction) sides of the outer frame 140 and formed to cover the battery cell stack 120. The busbar frame assemblies 180 and 190 can electrically connect the battery cells 110 constituting the battery cell stack 120 in series or parallel.

[0065] In this embodiment, the battery assembly 100 can be formed by electrically connecting a first battery cell stack 120a and a second battery cell stack 120b along the longitudinal direction (x-axis direction) of the battery cell 110. Specifically, the battery assembly 100 in this embodiment can be formed by electrically connecting a first busbar frame assembly 180 located at the other end of the first battery cell stack 120a and a second busbar frame assembly 190 located at one end of the second battery cell stack 120b.

[0066] The busbar frame assemblies 180 and 190 may include electrically insulating materials.

[0067] On the other hand, a flexible printed circuit board 330 can be provided to electrically connect the first busbar frame assembly 180 and the second busbar frame assembly 190. The flexible printed circuit board 330 is configured to extend and be mounted in the longitudinal direction of the battery cell 110 to sense the battery cell 110. That is, as shown in Figure 5, the flexible printed circuit board 330 is located on the upper surface of the battery cell stack 120 and senses voltage data and thermal data of the battery cell 110. In particular, the flexible printed circuit board 330 can be bent at one end toward the busbar frame assemblies 180 and 190 and electrically connected. This allows it to sense the voltage data of each battery cell 110 and transmit it to the outside.

[0068] Figure 12 is an exploded perspective view showing the insulating plate 200 between battery cell stacks 120. Figure 13 is a perspective view showing the insulating plate 200 according to one embodiment of the present invention.

[0069] Referring to Figures 12 and 13, a battery assembly 100 according to one embodiment of the present invention may further include an insulating plate 200 that is fastened between the first busbar frame assembly 180 and the second busbar frame assembly 190, with at least one of the first busbar frame assembly 180 or the second busbar frame assembly 190.

[0070] The insulating plate 200 may be made of an electrically insulating material. For example, the insulating plate 200 may be a plastic injection molded product.

[0071] The first battery cell stack 120a and the second battery cell stack 120b can all be contained within a single outer frame 140. Therefore, 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 busbar frame assembly 180 located on the other side of the first battery cell stack 120a and the second busbar frame assembly 190 located on one side of the second battery cell stack 120b.

[0072] Therefore, in this embodiment, an insulating plate 200 having electrical insulation properties was placed between the first battery cell stack 120a and the second battery cell stack 120b. The insulating plate 200 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 busbar frame assembly 180 and the second busbar frame assembly 190.

[0073] Referring again to Figures 11 to 13, an insulating plate 200 according to one embodiment of the present invention may include flow path holes 201 through which a refrigerant can move. The refrigerant can move between the first battery cell stack 120a and the second battery cell stack 120b through the flow path holes 201.

[0074] By forming a flow path hole 201 through which the refrigerant passes in the center of the insulating plate 200, stagnation of the refrigerant flow in the space between the first battery cell stack 120a and the second battery cell stack 120b is prevented. This ensures smooth refrigerant flow and improves cooling performance.

[0075] Specifically, the battery assembly 100 according to this embodiment includes a first battery cell stack 120a and a second battery cell stack 120b, and has a configuration that extends along the length direction. When the refrigerant circulates inside the outer frame 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. By designing the insulating plate 200 such that a flow path hole 201 through which the refrigerant passes is formed in the center of the insulating plate 200, the 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 ensure the flow of the refrigerant and improve cooling performance.

[0076] As described above, a flow path hole 201 through which the refrigerant passes is formed in the insulating plate 200. For example, the flow path hole 201 can be formed in the center of the insulating plate 200. More specifically, the flow path hole 201 can be opened in a rectangular shape, with the top and bottom edges being longer than the sides. In other words, the flow path hole 201 can be opened so as to be long and continuous along the direction in which the battery cells 110 are stacked.

[0077] The flow path hole 201 in this embodiment can be opened such that its area is between 5% and 60% of the area of ​​one surface of the insulating plate 200. Here, the area of ​​one surface of the insulating plate 200 can be the area including the opening area of ​​the flow path hole 201. In other words, assuming that the flow path hole 201 is clogged, the area of ​​one surface of the insulating plate 200 can be used as the basis for the above ratio.

[0078] If the area of ​​the flow path hole 201 is less than 5% of the area of ​​one surface of the insulating plate 200, the area through which the refrigerant passes may be too narrow, potentially obstructing the flow of the refrigerant. Also, if the area of ​​the flow path hole 201 is more than 60% of the area of ​​one surface of the insulating plate 200, the area of ​​the flow path hole 201 is too large, making it impossible to resolve the stagnation of the refrigerant flow in the space between the first battery cell stack 120a and the second battery cell stack 120b, which poses a risk of a short circuit occurring between the first battery cell stack 120a and the second battery cell stack 120b.

[0079] On the other hand, the insulating plate 200 and the busbar frame assemblies 180 and 190 in this embodiment can be bolted together.

[0080] Referring again to Figure 12, the insulating plate 200 according to this embodiment can be fixed to at least one of the first busbar frame assembly 180 or the second busbar frame assembly 190. In other words, the insulating plate 200 according to one embodiment of the present invention can be fixed to either the first busbar frame assembly 180 or the second busbar frame assembly 190. Furthermore, the insulating plate 200 according to another embodiment of the present invention can be fixed to both the first busbar frame assembly 180 and the second busbar frame assembly 190.

[0081] For example, the insulating plate 200 according to this embodiment may include a mounting portion 202 for fixing to a first busbar frame assembly 180 or a second busbar frame assembly 190. The mounting portion 202 may protrude from the insulating plate 200 toward the first busbar frame assembly 180 or the second busbar frame assembly 190, and fastening holes may be formed in such a mounting portion 202.

[0082] For example, a portion of the mounting portion 202 can protrude toward the first busbar frame assembly 180, and the remaining portion of the mounting portion 202 can protrude toward the second busbar frame assembly 190. A bolt (not shown) can be fastened to the first busbar frame assembly 180 after passing through the fastening hole of the mounting portion 202 protruding toward the first busbar frame assembly 180. Another bolt can be fastened to the second busbar frame assembly 190 after passing through the fastening hole of the mounting portion 202 protruding toward the second busbar frame assembly 190. In particular, the mounting portion 202 can be formed adjacent to the upper or lower edge of the insulating plate 200. This allows bolts that have passed through the mounting portion 202 to be fastened to adjacent areas of the upper or lower edge of the first busbar frame assembly 180 or the second busbar frame assembly 190.

[0083] In the manner described above, the insulating plate 200 can be fixed to at least one of the first busbar frame assembly 180 or the second busbar frame assembly 190.

[0084] Through such fastening, the fixing force between the first battery cell stack 120a and the second battery cell stack 120b can be strengthened, thereby improving the vibration and shock performance of the battery assembly 100. However, this is an example in which the insulating plate 200 is fixed to at least one of the first busbar frame assembly 180 or the second busbar frame assembly 190, and it may be fixed in other ways.

[0085] Referring again to Figures 10 and 11, the inlet 160 and outlet 170 can be located on opposite sides of each other with respect to the insulating plate 200. The first battery cell stack 120a can be located between the inlet 160 and the insulating plate 200, and the second battery cell stack 120b can be located between the outlet 170 and the insulating plate 200.

[0086] With the inlet 160 and outlet 170 arranged in this manner, the refrigerant can maintain a unidirectional flow within the battery assembly 100. The refrigerant flowing in through the inlet 160 can sequentially pass through the first battery cell stack 120a, the flow path holes 201 in the insulating plate 200, and the second battery cell stack 120b, and be discharged through the outlet 170. In other words, the refrigerant can flow throughout the entire space inside the outer frame 140, evenly cooling all the battery cells 110.

[0087] The refrigerant that flows in through the inlet 160 can sequentially pass through the first battery cell stack 120a, the flow path hole 201 of the insulating plate 200, and the second battery cell stack 120b, and be discharged through the outlet 170.

[0088] As explained above, the refrigerant can directly cool the battery cell stack 120 and other electrical components, as well as the busbar frame assemblies 180 and 190, which generate heat within the battery assembly 100, by directly contacting them and transferring heat. Therefore, compared to indirectly cooling the battery assembly 100 using a heat sink or the like, as in the past, the cooling efficiency can be improved, thereby extending the battery life.

[0089] Figure 14 is a plan view of a cooling spacer 210 according to one embodiment of the present invention. Figure 15 is a perspective view of a cooling spacer 210 according to one embodiment of the present invention. Figure 16 is a cross-sectional view showing a cross-section obtained by cutting along the cutting line B-B' in Figure 3.

[0090] Referring to Figures 14 to 16, a battery assembly 100 according to one embodiment of the present invention may further include a cooling spacer 210 located at least one position among a plurality of battery cells 110.

[0091] The cooling spacer 210 can be a surface that contacts one side of a battery cell 110 located in the center of the battery cell stack 120. Specifically, one surface of the cooling spacer 210 can contact one side of a battery cell 110 opposite to the surface of the cooling spacer 210. The other surface of the cooling spacer 210 can contact one side of a battery cell 110 opposite to the other surface of the cooling spacer 210. In this case, although not shown in the drawings, an adhesive is interposed between one side of the battery cell 110 and one surface of the cooling spacer 210, and between the adjacent battery cell 110 and the other surface of the cooling spacer 210, so that the battery cell 110 and the cooling spacer 210 can be bonded and fixed together. For example, the adhesive member 220 can be an insulating tape.

[0092] The size of the cooling spacer 210 may be larger than the size of the battery cell 110. In other words, the height (in the z-axis direction) of the cooling spacer 210 may be greater than the height of the battery cell 110. In this case, the battery cell 110 can be positioned so that it is attached to the cooling spacer 210, not in contact with the outer frame 140, and appears to be floating inside the outer frame 140. Specifically, the upper and lower edges of the battery cell 110 can be positioned at a certain height from one end and the other end of the cooling spacer 210. More specifically, if the height (in the z-axis direction) of the cooling spacer 210 is higher than the height (in the z-axis direction) of the battery cell 110, the battery cell 110 can be bonded and fixed while being positioned in the center of the cooling spacer 210.

[0093] The cooling spacer 210 includes a plurality of cooling holes 211 that are arranged along its length, and the refrigerant is movable through the plurality of cooling holes 211.

[0094] In this case, the refrigerant is transferred by the heat generated from the battery cell 110, so the battery cell 110 located in the center of the battery cell stack 120 can be effectively cooled.

[0095] Referring again to Figures 7 and 8, the first adhesive member 220a can be positioned between the lower surface of the battery cell stack 120 and the lower surface portion 132 of the fixed frame 130. The first adhesive member 220a can be bonded to the lower surface of the battery cell stack 120 and the lower surface portion 132 of the fixed frame 130, respectively. The second adhesive member 220b can be positioned at least one location between the side surface of the battery cell stack 120 and the side surface portion 131 of the fixed frame 130. The second adhesive member 220b can be bonded to the side surface of the battery cell stack 120 and the side surface portion 131 of the fixed frame 130, respectively.

[0096] When stacking a large number of battery cells 110 to form a medium-to-large battery assembly 100, they tend to slip due to external impacts. Therefore, to prevent this and maintain a stable stacked structure of the battery cells 110, adhesive members 220, such as double-sided tape or chemical adhesives that bond through a chemical reaction during bonding, can be attached to the lower surface 132 and side surface 131 of the fixing frame 130 to maintain the stacked structure of the first battery cell stack 120a and the second battery cell stack 120b.

[0097] The adhesive member 220 can be made of resin. For example, the adhesive member 220 can be made of resin or the like. When the adhesive member 220 comes into contact with other components, it can bond with the other components as it hardens, thereby fixing and supporting them.

[0098] Therefore, the adhesive force between the first battery cell stack 120a and the second battery cell stack 120b and the fixed frame 130 can be made stronger. In this case, even if the battery assembly 100 is subjected to an external impact, the first battery cell stack 120a and the second battery cell stack 120b will not separate or detach from the fixed frame 130, thereby improving the safety and mechanical reliability of the battery.

[0099] Referring again to Figure 16, the battery assembly 100 according to one embodiment of the present invention may further include a cooling fin 240 located at least one location among the battery cells 110.

[0100] The cooling fins 240 can be positioned between multiple battery cells 110. For example, a cooling fin 240 can be positioned between every two battery cells 110. Specifically, one cooling fin 240 and another adjacent cooling fin 240 can be positioned with two battery cells 110 in between. However, this is just an example, and there is no particular limit to the number of battery cells 110 between the cooling fins 240.

[0101] However, the shape of the cooling fins 240 is not limited to what is shown in this drawing; any shape is possible as long as it can contact the battery cell 110 and secure the battery cell 110. For example, the cooling fins 240 can be L-shaped.

[0102] The cooling fins 240 can be made of metal. Specifically, the cooling fins 240 can be made of a metal with high thermal conductivity. Therefore, the cooling fins 240 can directly transfer heat generated from the battery cell 110 during charging and discharging. When heat is generated, it is transferred to the cooling fins 240 in contact with the sides of the battery cell 110, causing the battery cell 110 to be cooled first, and the coolant can then be used to cool the battery cell 110 secondarily by directly contacting its upper and lower surfaces. This allows for direct cooling of the upper and lower edge regions of the battery cell 110, which were previously relatively difficult to cool, thereby improving the cooling efficiency of the battery.

[0103] Furthermore, the cooling fins 240 can be fixed between the lower surface portion 132 of the fixed frame 130 and the upper surface portion 141 of the outer frame 140. Specifically, the upper end of the cooling fins 240 can contact the upper surface portion 141 of the outer frame 140, and the lower end of the cooling fins 240 can contact the lower surface portion 132 of the fixed frame 130. In this way, the cooling fins 240 can be fixed in a manner that is in close contact with both the upper surface portion 141 of the outer frame 140 and the lower surface portion 132 of the fixed frame 130. This allows the cooling fins 240 to be more firmly fixed and positioned within the outer frame 140.

[0104] Figure 17 is a perspective view showing a cooling fin according to one embodiment of the present invention. Figure 18 is a cross-sectional view of a battery assembly 100 according to another embodiment of the present invention.

[0105] Referring to Figures 17 and 18, a cooling fin 240 according to one embodiment of the present invention may include a main part 241 located between the battery cells 110, a first support part 242 extending perpendicularly to one surface of the main part 241 at the upper end of the main part 241, and a second support part 243 extending perpendicularly to one surface of the main part 241 at the lower end of the main part 241.

[0106] Specifically, the cooling fin 240 may include a main part 241 having a surface area corresponding to or larger than one side of the first battery cell 110, and a first support part 242 and a second support part 243 protruding from the upper end of the main part 241 parallel to the stacking direction (y-axis direction) of the battery cell stack 120.

[0107] One side of the first support part 242 can be positioned facing the battery cell 110. That is, one side of the first support part 242 can be positioned facing the top of the battery cell 110, and the top and bottom of the battery cell 110 can be fixed to the main part 241 while maintaining a certain height from the top 141 and bottom 142 of the outer frame 140. In other words, a certain space can be provided between the top 141 of the outer frame 140 and the top of the battery cell 110, and between the bottom 142 of the outer frame 140 and the bottom of the battery cell 110, and the refrigerant can move into this space. In this case, the distance between the top 141 of the outer frame 140 and the top of the battery cell 110 can correspond to the distance between the bottom 142 of the outer frame 140 and the bottom of the battery cell 110.

[0108] Furthermore, by positioning the battery cell 110 in the space between the first support part 242 and the second support part 243, the fixation of the battery cell 110 can be made even more robust. In particular, the first support part 242 and the second support part 243 can prevent the battery cell 110 from flowing in the z-axis direction as shown in Figure 18. In other words, the durability of the battery assembly 100 can be enhanced by preventing damage to the battery cell 110 and leakage of electrolyte that may occur due to the flow of the battery cell 110.

[0109] Referring again to Figure 18, the first support part 242 can contact the top portion 141 of the outer frame 140, and the second support part 243 can contact the bottom portion 132 of the fixed frame 130. In this way, the cooling fins 240 can be fixed in a manner that is in close contact with the top portion 141 of the outer frame 140 and the bottom portion 132 of the fixed frame 130, respectively. As a result, the cooling fins 240 can be fixed and positioned more firmly within the outer frame 140.

[0110] Figure 19 is an exploded perspective view of a battery pack 1000 according to one embodiment of the present invention.

[0111] Referring to Figure 19, another embodiment of the present invention provides a battery pack 1000 including a battery assembly 100.

[0112] A battery pack 1000 according to one embodiment of the present invention may include a lower pack frame 1100 on which a plurality of battery assemblies 100 are mounted, an upper pack frame 1200 located above the battery assemblies 100, and at least one venting section 2000 provided on the side of the lower pack frame 1100. Here, the lower pack frame 1100 and the upper pack frame 1200 can be joined to each other by welding or other means to seal the inside of the battery pack 1000. High-temperature venting gases discharged from the battery assemblies 100 in the space between the lower pack frame 1100 and the upper pack frame 1200 can be discharged to the outside through the venting section 2000.

[0113] One or more battery assemblies 100 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 1000.

[0114] The battery assembly 100 and battery pack 1000 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, but are not limited to these, and can be applied to a variety of devices that can use secondary batteries.

[0115] In this embodiment, terms indicating directions such as front, back, left, right, up, and down were used, but these terms are merely for explanatory convenience and can change depending on the position of the object being examined, the observer's position, etc.

[0116] Although preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements by those skilled in the art that utilize 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]

[0117] 100: Battery Assembly 110: Battery cell 120: Battery cell stack 130: Fixed frame 140: Outer frame 200: Insulating plate 210: Cooling Spacer 240: Cooling fins

Claims

1. A battery cell stack in which multiple battery cells are stacked, A fixed frame covering at least a portion of the battery cell stack, An outer frame in which the battery cell stack and the fixing frame are housed, The outer frame includes an inlet and an outlet for circulating a refrigerant inside the frame, The system further includes a cooling fin located at least one of the locations between the battery cells, The fixed frame includes a lower portion that covers the lower surface of the battery cell stack, The cooling fins are fixed between the lower surface of the fixed frame and the upper surface of the outer frame. The cooling fins are, The main part located between the aforementioned battery cells, A first support part extends perpendicularly to one surface of the main part at the upper end of the main part, A battery assembly including a second support part that extends perpendicularly to one surface of the main part at the lower end of the main part.

2. The battery cell stack includes a first battery cell stack and a second battery cell stack. The battery assembly according to claim 1, wherein the first battery cell stack and the second battery cell stack are fixed to the fixed frame.

3. The fixed frame includes side portions that cover both sides of the battery cell stack, The battery assembly according to claim 1, wherein both side portions of the fixed frame are in surface contact with each of the battery cells located furthest out in the battery cell stack.

4. The battery cell stack includes a first battery cell stack and a second battery cell stack. The battery assembly according to claim 1, comprising a first busbar frame assembly provided on one side of the first battery cell stack and a second busbar frame assembly provided on one side of the second battery cell stack.

5. The battery assembly according to claim 4, further comprising an insulating plate fastened between the first busbar frame assembly and the second busbar frame assembly to at least one of the first busbar frame assembly or the second busbar frame assembly.

6. The insulating plate includes a flow path hole through which the refrigerant can move. The battery assembly according to claim 5, wherein the refrigerant moves between the first battery cell stack and the second battery cell stack through the flow path hole.

7. The battery assembly according to claim 5, wherein the insulating plate and the busbar frame assembly are bolted together.

8. The battery assembly according to claim 5, wherein the inlet and the outlet are located on opposite sides of the insulating plate with respect to it.

9. The first battery cell stack is positioned between the inlet and the insulating plate. The battery assembly according to claim 8, wherein the second battery cell stack is located between the outlet and the insulating plate.

10. The battery assembly according to claim 9, wherein the refrigerant that flows in through the inlet passes sequentially through the first battery cell stack, the flow path holes in the insulating plate, and the second battery cell stack, and is discharged through the outlet.

11. The system further includes a cooling spacer located at least one of the plurality of battery cells, The cooling spacer includes a plurality of cooling holes arranged along its length, The battery assembly according to claim 1, wherein the refrigerant is movable through the plurality of cooling holes.

12. The fixed frame includes a lower portion that covers the lower surface of the battery cell stack, The first adhesive member is positioned between the lower surface of the battery cell stack and the lower portion of the fixing frame. The battery assembly according to claim 1, wherein the first adhesive member is bonded to the lower surface of the battery cell stack and to the lower surface portion of the fixing frame, respectively.

13. The fixed frame includes side portions that cover both sides of the battery cell stack, The second adhesive member is located at least one location between the side surface of the battery cell stack and the side surface of the fixing frame, The battery assembly according to claim 1, wherein the second adhesive member is bonded to the side surface of the battery cell stack and to the side surface of the fixing frame, respectively.

14. The first support part contacts the ceiling portion of the outer frame, The battery assembly according to claim 1, wherein the second support part is in contact with the lower surface of the fixed frame.

15. A battery pack comprising the battery assembly described in any one of claims 1 to 14.

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