Battery assembly and battery pack including same

Abstract

A battery assembly according to one embodiment of the present invention comprises: a battery cell stack in which a plurality of battery cells are stacked; a fixing 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 accommodated; and an inlet and an outlet for circulating a refrigerant into the outer frame.

Description

Battery assembly and battery pack including same

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

[0002] This application claims the benefit of priority to Korean Patent Application No. 10-2024-0021641, filed February 15, 2024, and Korean Patent Application No. 10-2025-0015066, filed February 6, 2025, the entire contents of which are incorporated herein by reference.

[0003] The present invention relates to a battery assembly and a battery pack including the same, and more particularly, to a battery assembly and a battery pack including the same, which have improved cooling performance and enhanced fixing force of battery cells, thereby improving vibration and shock performance of the battery assembly.

[0004] As technological developments and demand for mobile devices increase, the demand for secondary batteries as an energy source is rapidly increasing. Accordingly, extensive research is being conducted on secondary batteries that can meet diverse needs.

[0005] Secondary batteries are attracting much attention not only as an energy source for mobile devices such as cell phones, digital cameras, and laptops, but also as a power source for power devices such as electric bicycles, electric cars, and hybrid electric vehicles.

[0006] Recently, as the need for large-capacity secondary battery structures has increased, including the use of secondary batteries as energy storage sources, the demand for battery packs with medium- to large-sized module structures that collect battery assemblies in which multiple secondary batteries are connected in series / parallel is increasing.

[0007] Meanwhile, when configuring a battery pack by connecting multiple battery cells in series / parallel, it is common to configure a battery assembly composed of at least one battery cell and configure a battery pack by adding other components using at least one battery assembly.

[0008] The battery cells that make up these medium- to large-sized battery assemblies are composed of rechargeable secondary batteries. Therefore, these high-power, high-capacity secondary batteries generate a large amount of heat during the charging and discharging process. In this case, the heat from multiple battery cells accumulates in a confined space, causing the temperature to rise rapidly and severely. In other words, while battery assemblies comprising multiple stacked battery cells and battery packs equipped with these battery assemblies can achieve high output, it is difficult to remove the heat generated by the battery cells during charging and discharging. If the battery cells are not properly dissipated, their deterioration will accelerate, shortening their lifespan and increasing the risk of explosion or fire.

[0009] Moreover, battery assemblies included in vehicle battery packs are frequently exposed to direct sunlight and may be subjected to high-temperature conditions, such as summer or desert environments. Furthermore, because multiple battery assemblies are densely packed together to increase vehicle range, flames or heat generated from one battery assembly can easily spread to neighboring ones, ultimately leading to fire or explosion within the battery pack itself.

[0010] Figure 1 is an exploded perspective view of a conventional battery pack.

[0011] Referring to FIG. 1, a conventional battery pack (10) includes a lower pack frame (11) on which a plurality of battery assemblies (1) are mounted, an upper pack frame (12) positioned above the battery assemblies (1), and an internal beam (13) that defines a location where the battery assemblies (1) are mounted within the battery pack (10).

[0012] In this way, when the battery assembly (1) is mounted inside the battery pack (10), the energy density of the battery pack (10) is reduced due to the internal beam (13) that partitions between the battery assemblies (1), so there is a problem that a larger number of battery packs (10) must be equipped to meet the efficiency required in the device, etc. In addition, there is a limit to the number of battery packs (10) that can be equipped in the device due to the weight of the battery pack (10). Therefore, the weight of the battery pack (10) must be reduced while at the same time reducing the energy density of the battery pack (10), so that a larger number of battery assemblies (1) must be mounted inside the battery pack (10).

[0013] Fig. 2 is a cross-sectional view showing the battery assembly of Fig. 1.

[0014] Referring to Fig. 2, a conventional battery assembly (1) includes a battery cell stack (3) including battery cells (2) stacked in a preset direction, and an outer frame (4) for accommodating the battery cell stack (3), and the battery cell stack (3) is fixedly positioned on a thermally conductive resin layer (5) positioned on the lower surface of the outer frame (4). In this case, in order to cool the heat generated in the battery cell stack (3), a heat sink (6) may be provided that is in contact with the bottom portion of the outer frame (4) positioned in the -z-axis direction of Fig. 3.

[0015] However, the heat sink (6) has a disadvantage in that its cooling efficiency is not very high because it does not receive heat by directly contacting the battery cell stack (3), and therefore, a method for cooling the battery assembly (1) more effectively is needed.

[0016] The problem to be solved by the present invention is to provide a battery assembly and a battery pack including the same, in which the vibration and impact performance of the battery assembly is improved by strengthening the fixing force of the battery cell.

[0017] However, the problems to be solved by the embodiments of the present invention are not limited to the problems described above and can be expanded in various ways within the scope of the technical ideas included in the present invention.

[0018] 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 in which the battery cell stack and the fixed frame are accommodated; and an inlet and an outlet for circulating a coolant into the interior of the outer frame.

[0019] The battery cell stack may include a first battery cell stack and a second battery cell stack arranged along a longitudinal direction in which electrode leads protrude from the battery cells. The first battery cell stack and the second battery cell stack may be fixed to the fixed frame.

[0020] The fixed frame may include side portions covering both sides of the battery cell stack, and the both side portions of the fixed frame may be in surface contact with each of the battery cells located at the outermost end of the battery cell stack.

[0021] The battery cell stack may include a first battery cell stack and a second battery cell stack. 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 may be provided.

[0022] The battery assembly may further include an insulating plate between the first busbar frame assembly and the second busbar frame assembly, the insulating plate being fastened to at least one of the first busbar frame assembly or the second busbar frame assembly.

[0023] The above insulating plate may include a flow hole through which the coolant can move. The coolant can move between the first battery cell stack and the second battery cell stack through the flow hole.

[0024] The above insulating plate and the above busbar frame assemblies can be bolted together.

[0025] Based on the above insulating plate, the inlet and the outlet may be located on opposite sides of each other.

[0026] The first battery cell stack may be positioned between the inlet and the insulating plate, and the second battery cell stack may be positioned between the outlet and the insulating plate.

[0027] The refrigerant introduced through the inlet may sequentially pass through the first battery cell stack, the flow hole included in the insulating plate, and the second battery cell stack, and be discharged through the outlet.

[0028] The battery assembly may further include a cooling spacer positioned between at least one of the plurality of battery cells. The cooling spacer may include a plurality of cooling holes formed along a longitudinal direction, and the coolant may be movable into the plurality of cooling holes.

[0029] The above fixed frame may include a lower surface covering a lower surface of the battery cell stack. A first adhesive member may be positioned between the lower surface of the battery cell stack and the lower surface of the fixed frame. The first adhesive member may be bonded to each of the lower surface of the battery cell stack and the lower surface of the fixed frame.

[0030] The fixed frame may include side portions covering both sides of the battery cell stack. A second adhesive member may be positioned at least between the side of the battery cell stack and the side portion of the fixed frame. The second adhesive member may be bonded to each of the side of the battery cell stack and the side portion of the fixed frame.

[0031] The battery assembly may further include a cooling fin positioned at least one between the battery cells, the fixed frame may include a lower portion covering a lower surface of the battery cell stack, and the cooling fin may be fixed between the lower portion of the fixed frame and the ceiling portion of the outer frame.

[0032] The cooling fin may include a main part positioned between the battery cells; a first support part extending vertically from an upper portion of the main part to one side of the main part; and a second support part extending vertically from a lower portion of the main part to one side of the main part.

[0033] The first support part can be in contact with the ceiling portion of the outer frame, and the second support part can be in contact with the lower portion of the fixed frame.

[0034] According to another embodiment of the present invention, a battery pack including the battery assembly is provided.

[0035] According to embodiments of the present invention, the energy density of a battery pack can be improved by electrically connecting each battery assembly.

[0036] In addition, by more effectively cooling the upper and lower surfaces of the battery cells, cooling efficiency can be improved, thereby ensuring the safety of the battery assembly and battery pack.

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

[0038] Figure 1 is an exploded perspective view of a conventional battery pack.

[0039] Fig. 2 is a cross-sectional view showing the battery assembly of Fig. 1.

[0040] FIG. 3 is a perspective view showing a battery assembly according to one embodiment of the present invention.

[0041] FIG. 4 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, a first busbar frame assembly, etc.

[0042] FIG. 5 is an exploded perspective view showing a first battery cell stack, a first busbar frame assembly, and a flexible printed circuit board.

[0043] Figure 6 is an exploded perspective view excluding the fixed frame and outer frame of Figure 3.

[0044] Figure 7 is an exploded perspective view of Figure 6 with a fixed frame added.

[0045] Figure 8 is a perspective view showing the lower part of Figure 7 at a different angle.

[0046] Figure 9 is a drawing showing Figure 7 being inserted into an outer frame.

[0047] Figure 10 is a perspective view showing where the coolant is located within the battery assembly.

[0048] FIG. 11 is a plan view from above of a battery assembly according to one embodiment of the present invention, with the upper portion of the outer frame omitted.

[0049] Figure 12 is an exploded perspective view showing an insulating plate between battery cell stacks.

[0050] Fig. 13 is a perspective view showing an insulating plate according to one embodiment of the present invention.

[0051] Figure 14 is a plan view of a cooling spacer according to one embodiment of the present invention.

[0052] Figure 15 is a perspective view of a cooling spacer according to one embodiment of the present invention.

[0053] Fig. 16 is a cross-sectional view showing a cross-section taken along the cutting line B-B' of Fig. 3.

[0054] Figure 17 is a perspective view showing a cooling fin according to one embodiment of the present invention.

[0055] FIG. 18 is a cross-sectional view of a battery assembly according to another embodiment of the present invention.

[0056] Figure 19 is an exploded perspective view of a battery pack according to one embodiment of the present invention.

[0057] Hereinafter, various embodiments of the present invention will be described in detail with reference to the attached drawings so that those skilled in the art can easily implement the invention. The present invention may be implemented in various different forms and is not limited to the embodiments described herein.

[0058] In order to clearly explain the present invention, parts that are not related to the description are omitted, and the same reference numerals are used for identical or similar components throughout the specification.

[0059] Furthermore, the sizes and thicknesses of each component shown in the drawings are arbitrarily indicated for convenience of explanation, and thus the present invention is not necessarily limited to the illustrated components. In the drawings, the thicknesses are enlarged to clearly represent various layers and regions. Furthermore, in the drawings, the thicknesses of some layers and regions are exaggerated for convenience of explanation.

[0060] Furthermore, when we say that a layer, membrane, region, plate, or other part is "on" or "over" another part, this includes not only cases where it is "directly on" the other part, but also cases where there are other parts in between. Conversely, when we say that a part is "directly on" another part, we mean that there are no other parts in between. Furthermore, saying that a part is "on" or "over" a reference part means that it is located above or below the reference part, and does not necessarily mean that it is located "above" or "over" the reference part in the opposite direction of gravity.

[0061] Additionally, throughout the specification, whenever a part is said to "include" a component, this does not mean that it excludes other components, but rather that it may include other components, unless otherwise specifically stated.

[0062] Additionally, throughout the specification, when we say "in plan", we mean when the target portion is viewed from above, and when we say "in cross section", we mean when the target portion is viewed from the side in a cross-section cut vertically.

[0063] FIG. 3 is a perspective view showing a battery assembly (100) according to one embodiment of the present invention. FIG. 4 is a perspective view showing components included in the battery assembly (100) according to one embodiment of the present invention, such as a first battery cell stack (120a), a first busbar frame assembly (180), and a flexible printed circuit board (330). FIG. 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). FIG. 6 is an exploded perspective view excluding the outer frame (140) of FIG. 3 and the fixed frame (130) of FIG. 8. FIG. 7 is an exploded perspective view of FIG. 6 with the fixed frame (130) added. FIG. 8 is a perspective view showing the lower part of FIG. 7 at a different angle so that it is visible. FIG. 9 is a drawing showing the component of FIG. 7 being inserted into the outer frame (140). Fig. 10 is a perspective view showing that the coolant is positioned within the battery assembly (100). Fig. 11 is a plan view from above showing the battery assembly (100) according to one embodiment of the present invention, with the upper portion of the outer frame (140) omitted.

[0064] Referring to FIGS. 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) covering at least a portion of the battery cell stack (120); an outer frame (140) in which the battery cell stack (120) and the fixed frame (130) are accommodated; and an inlet (160) and an outlet (170) for circulating a coolant into the interior of the outer frame (140).

[0065] First, the battery cell (110) may be a pouch-shaped battery cell. Such a pouch-shaped battery cell may be formed by housing an electrode assembly in a pouch case made of a laminate sheet including a resin layer and a metal layer, and then heat-sealing the sealing portion of the pouch case. In this case, the battery cell (110) may be formed into a rectangular sheet-shaped structure.

[0066] These battery cells (110) may be configured in multiple units, and the multiple battery cells (110) may be stacked so as to be electrically connected to each other to form a battery cell stack (120). In particular, as illustrated in FIG. 4, the multiple battery cells (110) may be stacked along a direction parallel to the y-axis direction. As described above, the direction in which the multiple battery cells (110) are stacked may be defined as the width direction of the battery cell stack (120).

[0067] 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 the lower side and a portion of the side surface of the battery cell stack (120).

[0068] The outer frame (140) may be intended to protect the battery cell stack (120) and electrical components connected thereto from external physical impact. The outer frame (140) may accommodate the battery cell stack (120) and electrical components connected thereto in the internal space of the outer frame (140).

[0069] The structure of the outer frame (140) may vary. According to the present embodiment, the structure of the outer frame (140) may be a monoframe structure. Here, the monoframe may be in the form of a metal plate with an upper surface, a lower surface, and both side surfaces integrated. The monoframe may be manufactured by extrusion molding.

[0070] However, the structure of the outer frame (140) is not limited thereto, and as another example, the outer frame (140) may have a structure in which a U-shaped frame and an upper plate are combined. In this case, the U-shaped frame may be formed by combining or integrating the lower surface and both sides of the outer frame (140). At this time, each frame or plate constituting the U-shaped frame may be manufactured by press forming. In addition, the structure of the outer frame (140) may be provided as an L-shaped frame structure in addition to a mono-frame or a U-shaped frame, and may also be provided as various structures not described in the above-described examples.

[0071] The outer frame (140) may be provided in a form in which the front and back sides are open along the longitudinal direction (x-axis direction). Here, the longitudinal direction may be, as will be described later, the direction in which the electrode leads (111) protrude from the battery cells (110). In this case, the front and back sides of the battery cell stack (120) may not be covered by the outer frame (140). The front and back sides of the battery cell stack (120) may be covered by busbar frame assemblies (180, 190), etc., and through this, the front and back sides of the battery cell stack (120) may be protected from external physical impacts, etc.

[0072] In particular, referring to FIGS. 10 and 11, in the battery assembly (100) according to the present embodiment, the coolant may be introduced into the outer frame (140) through the inlet (160) and then discharged to the outside of the battery assembly (100) through the outlet (170). At this time, the coolant may be a fluid. However, since the coolant is in direct contact with the battery cell stack (120), other electrical components, and busbar frame assemblies (180, 190) within the battery assembly (100), it is necessary to be electrically insulated. Therefore, the coolant may be a material having insulating properties. For example, the coolant may be an insulating oil.

[0073] In the first direction (d1) and the second direction (d2) which are parallel to and opposite to the direction in which the battery cells (110) are stacked, the inlet (160) may be positioned offset in the first direction (d1) from the center of the battery cell stack (120) in the direction in which the battery cells (110) are stacked. The outlet (170) may be positioned offset in the second direction (d2) from the center of the battery cell stack (120) in the direction in which the battery cells (110) are stacked. That is, it is preferable that the inlet (160) and the outlet (170) are positioned on opposite sides based on the direction in which the battery cells (110) are stacked. The inlet (160) and the outlet (170) must be positioned in this manner so that the coolant can flow throughout the space inside the outer frame (140) and evenly cool all the battery cells (110). If the inlet (160) and the outlet (170) are located at the center of the battery cell stack (120) in the direction in which the battery cells (110) are stacked, the coolant will only flow to the center, which is the part with the least flow resistance, and thus the coolant will not flow well to the battery cells (110) located at the outer part of the battery cell stack (120). Ultimately, this causes a cooling imbalance inside the battery assembly (100). In addition, if the inlet (160) and the outlet (170) are located so as to be biased toward only one of the first direction (d1) and the second direction (d2), the coolant will only flow to some of the outer battery cells (110) adjacent to the biased direction, and thus a cooling imbalance will also occur inside the battery assembly (100). Therefore, in order to induce the coolant to flow evenly through all of the battery cells (110) inside the battery assembly (100), as mentioned above, it is preferable that the inlet (160) and the outlet (170) be positioned on opposite sides based on the direction in which the battery cells (110) are stacked.

[0074] The end plate (300) may be positioned on the first open side (x-axis direction) and the second side (-x-axis direction) of the outer frame (140). The end plate (300) positioned on the first open side of the outer frame (140) may be a first end plate (310), and the end plate (300) positioned on the second open side of the outer frame (140) may be a second end plate (320). This end plate (300) may physically protect the battery cell stack (120) and other electrical components from external impact.

[0075] The inlet (160) may be a hole including a protrusion (not shown) protruding in the opposite direction to the area where the outer frame (140) is arranged. The protrusion may be positioned so as to penetrate the inlet opening (not shown) formed in the first end plate (310).

[0076] The outlet (170) may be a hole including a protrusion (not shown) protruding in the opposite direction to the area where the outer frame (140) is arranged. The protrusion may be positioned while penetrating an outlet opening (not shown) formed in the second end plate (320).

[0077] 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 a longitudinal direction in which electrode leads (111) protrude from battery cells (110). The first battery cell stack (120a) and the second battery cell stack (120b) are fixed to a fixed frame (130).

[0078] Specifically, the battery assembly (100) of the present embodiment may be one in which one end and the other end of each battery cell stack (120) constituting two conventional battery assemblies (100) are electrically connected. In other words, the first battery cell stack (120a) and the second battery cell stack (120b) may be electrically coupled.

[0079] The fixed frame (130) is formed of a material having rigidity, and can play a role in protecting the battery cell stack (120) from external physical impact and firmly fixing and supporting them within the outer frame (140).

[0080] Referring again to FIGS. 7 and 8, the fixed frame (130) according to one embodiment of the present invention may include side portions (131) covering both side surfaces of the battery cell stack (120) and a lower surface portion (132) covering the lower surface of the battery cell stack (120). This may correspond to one exemplary structure of the fixed frame (130). The two side portions (131) of the fixed frame (130) may be in surface contact with each of the battery cells (110) located at the outermost ends of the battery cell stack (120).

[0081] 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. Through this, the battery cells (110) can be protected from external physical impact, and the vibration and impact performance of the battery assembly (100) can be improved.

[0082] Referring again to FIGS. 4 to 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 a first battery cell stack (120a); and a second busbar frame assembly (190) provided on one side of a second battery cell stack (120b).

[0083] Busbar frame assemblies (180, 190) may be formed to cover the battery cell stack (120) by being positioned on the open first side (x-axis direction) and second side (-x-axis direction) of the outer frame (140). The busbar frame assemblies (180, 190) may electrically connect the battery cells (110) constituting the battery cell stack (120) in series or in parallel.

[0084] The battery assembly (100) according to the present embodiment 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, a first bus bar frame assembly (180) located at the other end of the first battery cell stack (120a) and a second bus bar frame assembly (190) located at one end of the second battery cell stack (120b) can be electrically connected to form the battery assembly (100) according to the present embodiment.

[0085] The busbar frame assemblies (180, 190) may comprise an electrically insulating material.

[0086] Meanwhile, a flexible printed circuit board (330) may 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 cells (110) and sense the battery cells (110). That is, as shown in FIG. 5, the flexible printed circuit board (330) is positioned on the upper surface of the battery cell stack (120) and senses voltage data or thermal data of the battery cells (110). In particular, the flexible printed circuit board (330) may be electrically connected while being bent toward the busbar frame assemblies (180, 190) at one end. Accordingly, the voltage data of each battery cell (110) can be sensed and transmitted to the outside.

[0087] Fig. 12 is an exploded perspective view showing an insulating plate (200) between battery cell stacks (120). Fig. 13 is a perspective view showing an insulating plate (200) according to one embodiment of the present invention.

[0088] Referring to FIGS. 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 to at least one of the first busbar frame assembly (180) and the second busbar frame assembly (190) between the first busbar frame assembly (180) and the second busbar frame assembly (190).

[0089] The insulating plate (200) may include a material having electrical insulating properties. For example, the insulating plate (200) may be a plastic injection molded product.

[0090] Both the first battery cell stack (120a) and the second battery cell stack (120b) may be included within one outer frame (140). Therefore, there is a risk of a short circuit occurring due to contact between the first battery cell stack (120a) and the second battery cell stack (120b) or contact 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).

[0091] Accordingly, in this embodiment, an insulating plate (200) having electrical insulation was placed between the first battery cell stack (120a) and the second battery cell stack (120b). By using the insulating plate (200), electrical insulation and creepage distance were secured 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).

[0092] Referring again to FIGS. 11 to 13, the insulating plate (200) according to one embodiment of the present invention may include a flow path hole (201) through which a coolant may move. The coolant may move between the first battery cell stack (120a) and the second battery cell stack (120b) through the flow path hole (201).

[0093] By forming a flow hole (201) through which a coolant passes in the center of the insulating plate (200), the flow of the coolant can be prevented from stagnating in the space between the first battery cell stack (120a) and the second battery cell stack (120b). This ensures the flowability of the coolant, thereby enhancing cooling performance.

[0094] Specifically, the battery assembly (100) according to the present embodiment has a shape extending in the longitudinal direction, including a first battery cell stack (120a) and a second battery cell stack (120b). When the coolant circulates inside the outer frame (200), a section where the flow of the coolant stagnates may occur between the first battery cell stack (120a) and the second battery cell stack (120b). By designing the insulating plate (200) so that a flow path hole (201) through which the coolant passes is formed at the center of the insulating plate (200), the flow stagnation of the coolant is prevented from occurring in the space between the first battery cell stack (120a) and the second battery cell stack (120b). In other words, the flowability of the coolant was secured to enhance cooling performance.

[0095] As described above, a flow path hole (201) through which a coolant passes may be formed in the insulating plate (200). For example, the flow path hole (201) may be formed in the center of the insulating plate (200). More specifically, the flow path hole (201) may be opened in a rectangular shape in which the upper and lower sides are longer than the two side sides. That is, the flow path hole (201) may be opened so as to extend along the direction in which the battery cells (110) are stacked.

[0096] The euro hole (201) according to the present embodiment may be opened to have an area of ​​5% or more and 60% or less of the area of ​​one side of the insulating plate (200). Here, the area of ​​one side of the insulating plate (200) may be an area including the opening area of ​​the euro hole (201). That is, assuming that the euro hole (201) is blocked, the area of ​​one side of the insulating plate (200) may serve as a reference for the above ratio.

[0097] If the area of ​​the flow path hole (201) is less than 5% of the area of ​​one side of the insulating plate (200), the area through which the refrigerant passes may be too narrow, which may impede the flow of the refrigerant. In addition, if the area of ​​the flow path hole (201) is more than 60% of the area of ​​one side of the insulating plate (200), the area of ​​the flow path hole (201) is too large, which may prevent the flow of the refrigerant from being stagnant in the space between the first battery cell stack (120a) and the second battery cell stack (120b), and there is a risk of a short circuit occurring between the first battery cell stack (120a) and the second battery cell stack (120b).

[0098] Meanwhile, the insulating plate (200) and busbar frame assemblies (180, 190) according to the present embodiment can be bolted together.

[0099] Referring again to FIG. 12, the insulating plate (200) according to the present embodiment can be fixed to at least one of the first busbar frame assembly (180) or the second busbar frame assembly (190). That is, 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). In addition, 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).

[0100] For example, the insulating plate (200) according to the present embodiment may include a mounting portion (202) that is fixed to the first busbar frame assembly (180) or the 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 a fastening hole may be formed in the mounting portion (202).

[0101] For example, some of the mounting portions (202) may protrude toward the first busbar frame assembly (180), and the rest of the mounting portions (202) may protrude toward the second busbar frame assembly (190). A bolt (not shown) may pass through a fastening hole of the mounting portion (202) protruding toward the first busbar frame assembly (180) and then be fastened to the first busbar frame assembly (180). Additionally, another bolt may pass through a fastening hole of the mounting portion (202) protruding toward the second busbar frame assembly (190) and then be fastened to the second busbar frame assembly (190). In particular, the mounting portion (202) may be formed adjacent to an upper side or a lower side of the insulating plate (200). Accordingly, bolts passing through the mounting portion (202) can also be fastened to adjacent areas of the upper or lower sides of the first busbar frame assembly (180) or the second busbar frame assembly (190).

[0102] In the above manner, 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). Through this fixing, 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 impact 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 can be fixed in another manner.

[0103] Referring again to FIGS. 10 and 11, the inlet (160) and the outlet (170) may be positioned on opposite sides with respect to the insulating plate (200). The first battery cell stack (120a) may be positioned between the inlet (160) and the insulating plate (200), and the second battery cell stack (120b) may be positioned between the outlet (170) and the insulating plate (200).

[0104] The inlet (160) and outlet (170) must be arranged in this manner so that the coolant can maintain a one-way flow within the battery assembly (100). The coolant introduced 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). That is, the coolant can flow throughout the entire space within the outer frame (140) to evenly cool all battery cells (110).

[0105] The refrigerant introduced through the inlet (160) can sequentially pass through the first battery cell stack (120a), the flow hole (201) of the insulating plate (200), and the second battery cell stack (120b), and be discharged through the outlet (170).

[0106] As described above, the coolant can directly cool the battery cell stack (120) and other electrical components and busbar frame assemblies (180, 190) that generate heat within the battery assembly (100) by directly contacting them and receiving heat therefrom. 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 life of the battery.

[0107] Fig. 14 is a plan view of a cooling spacer (210) according to one embodiment of the present invention. Fig. 15 is a perspective view of a cooling spacer (210) according to one embodiment of the present invention. Fig. 16 is a cross-sectional view taken along the cutting line B-B' of Fig. 3.

[0108] Referring to FIGS. 14 to 16, a battery assembly (100) according to one embodiment of the present invention may further include a cooling spacer (210) positioned at least one location between a plurality of battery cells (110).

[0109] The cooling spacer (210) may be a surface that comes into contact with one side of the battery cells (110) located in the central portion of the battery cell stack (120). Specifically, one side of the cooling spacer (210) may come into contact with one side of the battery cell (110) that faces one side of the cooling spacer (210). The other side of the cooling spacer (210) may come into contact with one side of the battery cell (110) that faces the other side of the cooling spacer (210). In this case, although not shown in the drawing, an adhesive is interposed between one side of the battery cell (110) and one side of the cooling spacer (210), and between the other side of the adjacent battery cell (110) and the cooling spacer (210), so that the battery cell (110) and the cooling spacer (210) can be bonded together. For example, the adhesive member (220) may be an insulating tape.

[0110] The size of the cooling spacer (210) may be larger than the size of the battery cell (110). That is, the height (z-axis direction) of the cooling spacer (210) may be larger than the height of the battery cell (110). In this case, the battery cell (110) may be attached to the cooling spacer (210) and positioned as if floating inside the outer frame (140) without coming into contact with the outer frame (140). Specifically, the upper and lower edges of the battery cell (110) may be positioned at a constant height from one end and the other end of the cooling spacer (210). More specifically, when the height (z-axis direction) of the cooling spacer (210) is higher than the height (z-axis direction) of the battery cell (110), the battery cell (110) may be positioned at the center of the cooling spacer (210) and may be adhesively fixed thereto.

[0111] The cooling spacer (210) includes a plurality of cooling holes (211) formed along the length direction, and the refrigerant can move into the plurality of cooling holes (211).

[0112] In this case, the coolant moves while receiving heat generated from the battery cell (110), so it can effectively cool the battery cell (110) in the central portion of the battery cell stack (120).

[0113] Referring again to FIGS. 7 and 8, a first adhesive member (220a) may be positioned between the lower surface of the battery cell stack (120) and the lower surface (132) of the fixed frame (130). The first adhesive member (220a) may be adhered to the lower surface of the battery cell stack (120) and the lower surface (132) of the fixed frame (130), respectively. A second adhesive member (220b) may be positioned at least at one location between the side surface of the battery cell stack (120) and the side surface (131) of the fixed frame (130). The second adhesive member (220b) may be adhered to the side surface of the battery cell stack (120) and the side surface (131) of the fixed frame (130), respectively.

[0114] When stacking a plurality of battery cells (110) to form a medium- or large-sized battery assembly (100), there is a tendency for them to slip easily due to external impact. Therefore, in order to prevent this and maintain a stable stacked structure of the battery cells (110), an adhesive member (220), such as a double-sided tape or a chemical adhesive that bonds by a chemical reaction during bonding, may be attached to the lower surface (132) and the side surface (131) of the fixed frame (130), thereby maintaining the stacked structure of the first battery cell stack (120a) and the second battery cell stack (120b).

[0115] The adhesive members (220) may be formed of resin. For example, the adhesive members (220) may be formed of resin or the like. When the adhesive members (220) come into contact with other components, they may be hardened and then bonded to the other components to securely support them.

[0116] Accordingly, the adhesive strength between the first battery cell stack (120a) and the second battery cell stack (120b) and the fixed frame (130) can be made more solid. In this case, even if an impact is applied to the battery assembly (100) from the outside, the first battery cell stack (120a) and the second battery cell stack (120b) do not separate or detach from the fixed frame (130), thereby improving the safety and mechanical reliability of the battery.

[0117] Referring again to FIG. 16, the battery assembly (100) according to one embodiment of the present invention may further include cooling fins (240) positioned at at least one location between the battery cells (110).

[0118] Cooling fins (240) may be positioned between a plurality of battery cells (110). For example, cooling fins (240) may be positioned between every two battery cells (110). Specifically, one cooling fin (240) and another cooling fin (240) adjacent to it may be positioned with two battery cells (110) between them. However, this is merely an example, and there is no particular limitation on the number of battery cells (110) between cooling fins (240).

[0119] However, the shape of the cooling fin (240) is not limited to this drawing, and any shape is possible as long as it can secure the battery cell (110) while making contact with the battery cell (110). For example, the cooling fin (240) may be L-shaped.

[0120] The cooling fin (240) may be made of metal. Specifically, the cooling fin (240) may be made of a metal with high thermal conductivity. Therefore, the cooling fin (240) can directly receive heat generated from the battery cell (110) during charging and discharging. When heat is generated, the heat is transferred to the cooling fin (240) in contact with the side surface of the battery cell (110), thereby primarily cooling the battery cell (110), and the coolant can be secondarily cooled by directly contacting the upper and lower portions of the battery cell (110). Accordingly, direct cooling is possible even for the upper and lower edge regions of the battery cell (110), which were relatively difficult to cool in the past, thereby improving the cooling efficiency of the battery.

[0121] In addition, the cooling fin (240) can be fixed between the lower surface (132) of the fixed frame (130) and the ceiling surface (141) of the outer frame (140). Specifically, the upper surface of the cooling fin (240) can be in contact with the ceiling surface (141) of the outer frame (140), and the lower surface of the cooling fin (240) can be in contact with the lower surface (132) of the fixed frame (130). In this way, the cooling fin (240) can be fixed while being positioned in close contact with the ceiling surface (141) of the outer frame (140) and the lower surface (132) of the fixed frame (130). As a result, the cooling fin (240) can be more firmly fixed and positioned within the outer frame (140).

[0122] Fig. 17 is a perspective view showing a cooling fin according to one embodiment of the present invention. Fig. 18 is a cross-sectional view of a battery assembly (100) according to another embodiment of the present invention.

[0123] Referring to FIGS. 17 and 18, a cooling fin (240) according to one embodiment of the present invention may include a main part (241) positioned between battery cells (110); a first support part (242) extending vertically from an upper portion of the main part (241) to one surface of the main part (241); and a second support part (243) extending vertically from a lower portion of the main part (241) to one surface of the main part (241).

[0124] Specifically, the cooling fin (240) may include a main part (241) having a surface 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 top of the main part (241) in a manner parallel to the stacking direction (y-axis direction) of the battery cell stack (120).

[0125] One side of the first support part (242) may be positioned to face the battery cell (110). That is, one side of the first support part (242) may be positioned to face the upper part of the battery cell (110), and the upper and lower parts of the battery cell (110) may be positioned to be adhesively fixed to the main part (241) while having a certain height from the ceiling part (141) and the bottom part (142) of the outer frame (140). In other words, a certain space may be provided between the ceiling part (141) of the outer frame (140) and the upper part of the battery cell (110), and between the bottom part (142) of the outer frame (140) and the lower part of the battery cell (110), and the coolant may move into the space. In this case, the distance between the ceiling (141) of the outer frame (140) and the upper part of the battery cell (110) may correspond to the distance between the bottom (142) of the outer frame (140) and the lower part of the battery cell (110).

[0126] In addition, since the battery cell (110) is arranged 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 more solid. In particular, the movement of the battery cell (110) in the z-axis direction of FIG. 18 can be prevented by the first support part (242) and the second support part (243). That is, by preventing damage to the battery cell (110) and electrolyte leakage that may occur due to the movement of the battery cell (110), the durability of the battery assembly (100) can be enhanced.

[0127] Referring again to FIG. 18, the first support part (242) can be in contact with the ceiling part (141) of the outer frame (140), and the second support part (243) can be in contact with the lower surface (132) of the fixed frame (130). In this way, the cooling fin (240) can be positioned and fixed in close contact with the ceiling part (141) of the outer frame (140) and the lower surface (132) of the fixed frame (130), respectively. As a result, the cooling fin (240) can be positioned and fixed more firmly within the outer frame (140).

[0128] Figure 19 is an exploded perspective view of a battery pack (1000) according to one embodiment of the present invention.

[0129] Referring to FIG. 19, according to another embodiment of the present invention, a battery pack (1000) including a battery assembly (100) is provided.

[0130] 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) positioned above the battery assemblies (100), and at least one venting portion (2000) provided on a side surface of the lower pack frame (1100). Here, the lower pack frame (1100) and the upper pack frame (1200) may be joined to each other by a method such as welding, thereby sealing the inside of the battery pack (1000). High-temperature venting gas, etc. discharged from the battery assemblies (100) in the space between the lower pack frame (1100) and the upper pack frame (1200) may be discharged to the outside through the venting portion (2000).

[0131] 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 BMS (Battery Management System), a BDU (Battery Disconnect Unit), and a cooling system to form a battery pack (1000).

[0132] The above battery assembly (100) or battery pack (1000) can be applied to various devices. Specifically, it can be applied to means of transportation such as electric bicycles, electric vehicles, and hybrid vehicles, but is not limited thereto, and can be applied to various devices that can use secondary batteries.

[0133] In this example, terms indicating directions such as front, back, left, right, up, and down are used, but these terms are only for convenience of explanation and may vary depending on the location of the target object or the location of the observer.

[0134] Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements made by those skilled in the art using the basic concept of the present invention defined in the following claims also fall within the scope of the present invention.

[0135] Description of the symbol

[0136] 100: Battery assembly

[0137] 110: Battery cell

[0138] 120: Battery cell stack

[0139] 130: Fixed frame

[0140] 140: Outer frame

[0141] 200: Insulating plate

[0142] 210: Cooling spacer

[0143] 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 fixed frame are stored; and A battery assembly comprising an inlet and an outlet for circulating coolant into the interior of the outer frame.

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

3. In paragraph 1, The above fixed frame includes side portions covering both sides of the battery cell stack, A battery assembly, wherein the two side surfaces of the fixed frame are in surface contact with each of the battery cells located at the outermost end of the battery cell stack.

4. In paragraph 1, The battery cell stack includes a first battery cell stack and a second battery cell stack, A battery assembly 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. In paragraph 4, A battery assembly further comprising an insulating plate between the first busbar frame assembly and the second busbar frame assembly, the insulating plate being fastened to at least one of the first busbar frame assembly or the second busbar frame assembly.

6. In paragraph 5, The above insulating plate includes a flow hole through which the refrigerant can move, A battery assembly, wherein the coolant moves between the first battery cell stack and the second battery cell stack through the euro hole.

7. In paragraph 5, A battery assembly in which the above insulating plate and the above busbar frame assembly are bolted together.

8. In paragraph 5, A battery assembly wherein the inlet and the outlet are located on opposite sides of the insulating plate.

9. In paragraph 8, The first battery cell stack is positioned between the inlet and the insulating plate, A battery assembly, wherein the second battery cell stack is positioned between the outlet and the insulating plate.

10. In paragraph 9, A battery assembly in which the coolant introduced through the inlet sequentially passes through the first battery cell stack, the flow hole included in the insulating plate, and the second battery cell stack, and is discharged through the outlet.

11. In paragraph 1, Further comprising a cooling spacer positioned at least one between the plurality of battery cells, The above cooling spacer includes a plurality of cooling holes formed along the length direction, A battery assembly wherein the refrigerant is capable of moving through the plurality of cooling holes.

12. In paragraph 1, The above fixed frame includes a lower portion covering the lower surface of the battery cell stack, A first adhesive member is positioned between the lower surface of the battery cell stack and the lower surface of the fixed frame, A battery assembly, wherein the first adhesive member is adhered to the lower surface of the battery cell stack and the lower surface of the fixed frame, respectively.

13. In paragraph 1, The above fixed frame includes side portions covering both sides of the battery cell stack, A second adhesive member is positioned at least between the side surface of the battery cell stack and the side surface of the fixed frame, A battery assembly, wherein the second adhesive member is adhered to each of the side surfaces of the battery cell stack and the side surfaces of the fixed frame.

14. In paragraph 1, Further comprising a cooling fin positioned at least one between the battery cells, The above fixed frame includes a lower portion covering the lower surface of the battery cell stack, A battery assembly wherein the cooling fin is fixed between the lower surface of the fixed frame and the ceiling surface of the outer frame.

15. In paragraph 14, The above cooling fins are, A main part located between the above battery cells; A first support part extending perpendicularly to one side of the main part from the top of the main part; and A battery assembly comprising a second support part extending perpendicularly to one side of the main part from the lower portion of the main part.

16. In paragraph 15, The above first support part is in contact with the ceiling portion of the above outer frame, A battery assembly in which the second support part is in contact with the lower surface of the fixed frame.

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

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