Battery module and battery pack including same

Abstract

A battery module according to an embodiment of the present invention includes: a battery cell stack in which a plurality of battery cells are stacked; and at least one cooling member disposed on at least one of both side surfaces of the battery cell stack or between the plurality of battery cells. The cooling member includes: a cooling channel that is a space in which a refrigerant flows inside the cooling member; and an air gap which is an empty space separated from the cooling channel.

Description

Battery module and battery pack including the same

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

[0002] This application claims the benefit of priority to Korean Patent Application No. 10-2024-0020265, filed February 13, 2024, the entire contents of which are incorporated herein by reference.

[0003] The present invention relates to a battery module and a battery pack including the same.

[0004] In modern society, the widespread use of portable devices such as cell phones, laptops, camcorders, and digital cameras has led to active development of technologies related to these mobile devices. Furthermore, rechargeable secondary batteries are increasingly being used as power sources for electric vehicles (EVs), hybrid electric vehicles (HEVs), and plug-in hybrid electric vehicles (P-HEVs) to address air pollution issues associated with conventional gasoline-powered vehicles, fueled by fossil fuels. Consequently, the need for secondary battery development is increasing.

[0005] Secondary batteries can experience performance degradation and, in severe cases, even explosion or fire when exposed to temperatures exceeding their optimal levels. In battery modules or packs equipped with multiple secondary batteries, or battery cells, the heat generated by these cells accumulates within a confined space, causing the temperature to rise more rapidly and severely. While battery modules with multiple stacked cells and battery packs equipped with such modules can achieve high output, it is difficult to remove the heat generated by the cells during charging and discharging. If the heat dissipation of the battery cells is inadequate, the cells deteriorate more quickly, shortening their lifespan and increasing the risk of explosion or fire.

[0006] As secondary batteries in the form of battery modules and battery packs with multiple battery cells stacked in this way begin to be widely used, fire and explosion accidents are occurring, and the safety of secondary batteries is emerging as an increasingly important issue.

[0007]

[0008] In one embodiment of the present invention, a battery module having a structure capable of controlling swelling of battery cells and simultaneously improving cooling performance and a battery pack including the same are provided.

[0009] A battery module according to one embodiment of the present invention comprises: a battery cell stack in which a plurality of battery cells are stacked; and at least one cooling member disposed on at least one of both sides of the battery cell stack or between the plurality of battery cells. The cooling member includes a cooling channel, which is a space through which a coolant flows within the cooling member, and an air gap, which is an empty space separated from the cooling channel.

[0010] One surface of the cooling member may be in contact with one surface of at least one battery cell among the plurality of battery cells.

[0011] The above cooling member is in a plate shape and can cool at least one of the plurality of battery cells.

[0012] The air gap may include a first air gap and a second air gap, and the cooling channel may be located between the first air gap and the second air gap.

[0013] The first air gap, the cooling channel, and the second air gap may be positioned sequentially along the direction in which the plurality of battery cells are stacked.

[0014] The cooling channel may include a first cooling channel and a second cooling channel, and the air gap may be located between the first cooling channel and the second cooling channel.

[0015] The first cooling channel, the air gap, and the second cooling channel may be positioned sequentially along the direction in which the plurality of battery cells are stacked.

[0016] Each of the plurality of battery cells may include an electrode lead, and a busbar frame may be arranged in a direction in which the electrode leads protrude from the plurality of battery cells based on the battery cell stack, and a busbar may be mounted on the busbar frame.

[0017] The cooling member may include an inlet port for supplying the refrigerant to the cooling channel and an outlet port for discharging the refrigerant from the cooling channel. The inlet port and the outlet port may be connected to a pack refrigerant supply pipe and a pack refrigerant discharge pipe, respectively, by passing through the busbar frame.

[0018] The above inlet port and the above outlet port can extend further than the bus bar frame based on the battery cell stack.

[0019] A battery pack according to one embodiment of the present invention includes: a plurality of battery modules; a pack frame for accommodating the plurality of battery modules; and a pack coolant supply pipe and a pack coolant discharge pipe connected to the cooling member and accommodated in the pack frame.

[0020] The cooling member may include an inlet port connected to the pack coolant supply pipe and an outlet port connected to the pack coolant discharge pipe. The inlet port and the outlet port may be connected to the pack coolant supply pipe and the pack coolant discharge pipe, respectively, by passing through a bus bar frame arranged on one side of the battery cell stack.

[0021] The above pack coolant supply pipe and the above pack coolant discharge pipe can be arranged in a space between the plurality of battery modules and the side frame of the pack frame.

[0022] A vehicle according to one embodiment of the present invention includes the battery pack.

[0023] According to embodiments of the present invention, a cooling member having a cooling channel and an air gap is arranged adjacent to the battery cells, thereby controlling swelling of the battery cells and at the same time further increasing cooling performance for the battery cells.

[0024] 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.

[0025] The following drawings attached to this specification illustrate embodiments of the present invention and, together with the description of the invention described below, serve to further understand the technical idea of ​​the present invention, and therefore, the present invention should not be interpreted as being limited to matters described in such drawings.

[0026] Figure 1 is a perspective view of a conventional battery module.

[0027] Fig. 2 is a cross-sectional view showing a cross-section taken along the cutting line A-A' of Fig. 1.

[0028] Figure 3 is a perspective view showing a battery module according to one embodiment of the present invention.

[0029] Figure 4 is an exploded perspective view of the battery module of Figure 3.

[0030] FIG. 5 is an exploded perspective view showing a battery cell stack, a first busbar frame, and a second busbar frame included in the battery module of FIG. 4.

[0031] FIG. 6 is a perspective view showing one of the battery cells included in the battery cell stack of FIG. 5.

[0032] FIGS. 7 and 8 are perspective views showing battery cells and a cooling member according to one embodiment of the present invention.

[0033] Figure 9 is a perspective view showing a cooling member according to one embodiment of the present invention.

[0034] Fig. 10 is a partial perspective view showing the cooling member of Fig. 9 from a different angle.

[0035] Fig. 11 is a cross-sectional view showing a cross-section taken along the cutting line B-B' of Fig. 9.

[0036] Fig. 12 is a cross-sectional view showing a cooling member according to another embodiment of the present invention.

[0037] FIG. 13 is a perspective view showing a battery cell stack, a first busbar frame, and a second busbar frame according to one embodiment of the present invention.

[0038] FIG. 14 and FIG. 15 are a perspective view and a front view, respectively, showing a first busbar frame according to one embodiment of the present invention.

[0039] Figure 16 is a plan view showing a battery pack according to one embodiment of the present invention.

[0040] FIG. 17 is a perspective view illustrating a vehicle including a battery pack according to one embodiment of the present invention.

[0041] In some of the accompanying drawings, corresponding components are designated by the same reference numerals. Those skilled in the art will appreciate that the drawings illustrate elements simply and clearly and are not necessarily drawn to scale. For example, to facilitate understanding of various embodiments, the dimensions of some elements depicted in the drawings may be exaggerated relative to other elements. Furthermore, elements of known technology that are useful or essential in commercially feasible embodiments may often not be depicted so as not to obscure the spirit of various embodiments of the present invention.

[0042]

[0043] Hereinafter, various embodiments of the present invention will be described 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.

[0044] 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.

[0045] 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.

[0046] Furthermore, when we say that a layer, membrane, region, plate, or other part is "above" or "on" another part, this includes not only cases where it is "directly above" that part, but also cases where there are other parts in between. Conversely, when we say that a part is "directly above" another part, it means that there are no other parts in between. Furthermore, saying that a part is "above" or "on" a reference part means that it is located above or below that reference part, and does not necessarily mean that it is located "above" or "on" in the opposite direction of gravity.

[0047] 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.

[0048] 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.

[0049] Currently commercialized secondary batteries include nickel-cadmium batteries, nickel-hydrogen batteries, nickel-zinc batteries, and lithium secondary batteries. Among these, lithium secondary batteries have the advantage of having almost no memory effect compared to nickel-based secondary batteries, allowing free charging and discharging, a very low self-discharge rate, and high energy density.

[0050] Lithium secondary batteries can use lithium oxide and carbon materials as positive and negative active materials, respectively. Lithium secondary batteries can include an electrode assembly comprising positive and negative plates, each coated with a positive and negative active material, with a separator interposed between them, and a battery case that seals and houses the electrode assembly together with an electrolyte.

[0051] Lithium secondary batteries can be classified into can-type secondary batteries in which the electrode assembly is built into a metal can and pouch-type secondary batteries in which the electrode assembly is built into a pouch of an aluminum laminate sheet, depending on the shape of the outer packaging material.

[0052] In the case of secondary batteries used in small devices, 2-3 battery cells can be arranged, and in the case of secondary batteries used in medium to large devices such as automobiles, a battery module in which a plurality of battery cells are electrically connected can be used. Such a battery module can improve capacity and output by forming a battery cell stack by connecting a plurality of battery cells in series or parallel. One or more battery modules can be mounted together with various control and protection systems such as a battery management system (BMS), a battery disconnect unit (BDU), and a cooling system to form a battery pack.

[0053] A battery pack includes battery modules as a sub-concept, and a battery module includes battery cells as a sub-concept. The number of battery cells contained in a battery module or the number of battery modules contained in a battery pack can vary depending on the output or capacity of the battery pack required for the electric vehicle.

[0054] Battery modules included in vehicle battery packs are frequently exposed to direct sunlight and can be subjected to high-temperature conditions, such as summer or desert regions. When constructing battery modules or packs, ensuring stable and effective cooling performance is crucial. Cooling methods for battery modules or packs can be broadly categorized into water-cooling, which utilizes refrigerants such as coolant, and air-cooling, which utilizes cooling air. Among these, water-cooling offers superior cooling performance and can effectively dissipate the high heat generated by large-capacity battery modules or packs.

[0055] Fig. 1 is a perspective view of a conventional battery module, and Fig. 2 is a cross-sectional view taken along the cutting line A-A' of Fig. 1. However, for convenience of explanation, Fig. 2 additionally illustrates a heat sink (30) positioned below the battery module (10).

[0056] Referring to FIGS. 1 and 2, a conventional battery module (10) includes a battery cell stack (12) in which a plurality of battery cells (11) are stacked, and a module frame (20) that accommodates the battery cell stack (12). At this time, the battery cells (11) are pouch-shaped battery cells, and the pouch-shaped battery cells form a rectangular sheet structure.

[0057] Since a plurality of battery cells (11) are stacked, the battery module (10) generates a large amount of heat during the charging and discharging process. Conventionally, cooling of the battery module (10) was performed by implementing a heat transfer path from the edge portion of the battery cell (11) to the heat sink (30).

[0058] The battery module (10) may include a thermal resin layer (40) positioned between the battery cell stack (12) and the bottom of the module frame (20). In addition, when the battery module (10) is mounted on the pack frame to form a battery pack, a heat transfer member (50) and a heat sink (30) may be sequentially positioned under the battery module (10). The heat transfer member (50) may be a heat dissipation pad, and the heat sink (30) may include a cooling channel (31) through which a coolant such as coolant flows therein. The edges of the battery cells (11) stacked along one direction come into contact with the thermal resin layer (40), and heat generated from the battery cells (11) may be sequentially transferred to the outside of the battery module (10) through the thermal resin layer (40), the bottom of the module frame (20), the heat transfer member (50), and the heat sink (30). That is, a water-cooling structure that discharges heat through the edge portion of the battery cell (11) was applied to the conventional battery module (10).

[0059] A water-cooling structure utilizing the edge portion of a battery cell (11) like this has a relatively simplified structure, but has poor cooling performance, and there is a risk of cracks occurring in the pouch case of the battery cell (11) when high swelling of the battery cell (11) occurs.

[0060] In the battery cells (11), the internal electrolyte may decompose and gas may be generated during the process of repeated charging and discharging or the initial charging process, causing the battery cells (11) to swell, i.e., a swelling or breathing phenomenon may occur.

[0061] As the capacity of battery cells increases, the degree of swelling also increases significantly, and the number of battery cells applied to a battery module is also gradually increasing, so controlling the swelling of battery cells inside a battery module has become an important issue.

[0062] Referring again to Fig. 2, since the thermal resin layer (40) generally has adhesive properties to fix the battery cells (11), if swelling of the battery cells (11) occurs, high stress occurs at the edges of the battery cells (11), which may lead to cracks in the pouch case of the battery cells (11). The more the battery cells (11) are located on the outside of the battery cell stack (12), the greater the stress caused by swelling, and the greater the risk of cracks occurring.

[0063] If a conventional water cooling method utilizing edge portions is applied to a battery module including battery cells in which swelling occurs, there is a high risk of cracks occurring in the battery cells, and excessive stress may be applied, which may compromise the structural safety of the battery module.

[0064] Accordingly, there is a need for a battery module having a novel cooling structure that can control swelling of battery cells while simultaneously improving cooling performance.

[0065]

[0066] Fig. 3 is a perspective view illustrating a battery module according to one embodiment of the present invention. Fig. 4 is an exploded perspective view of the battery module of Fig. 3. Fig. 5 is an exploded perspective view illustrating a battery cell stack, a first busbar frame, and a second busbar frame included in the battery module of Fig. 4. Fig. 6 is a perspective view illustrating one of the battery cells included in the battery cell stack of Fig. 5.

[0067] Referring to FIGS. 3 to 6, a battery module (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; and at least one cooling member (600a) disposed on at least one of both sides of the battery cell stack (120) or between the battery cells (110). The cooling member (600a) may include a cooling channel, which is a space in which a coolant flows inside the cooling member (600a), and an air gap, which is an empty space separated from the cooling channel. The shape of the cooling member (600a) will be described later.

[0068] The battery cell (110) according to the present embodiment may be a battery cell of various shapes, for example, a pouch-shaped battery cell, a square battery cell, or a cylindrical battery cell. For example, as illustrated in FIGS. 4 to 6 , the battery cell (110) according to the present embodiment may be a pouch-shaped battery cell. Hereinafter, a pouch-shaped battery cell will be described, but the battery cell (110) according to the present embodiment is not limited thereto, and various types of battery cells may be applied.

[0069] The battery cell (110) according to the present embodiment may be in the form of an electrode assembly having electrode leads (111) protruding in one or both directions, housed in a pouch case (114). Such a battery cell (110) may have a rectangular sheet shape. The battery cell (110) may be formed by housing the electrode assembly in a pouch case (114) of a laminate sheet including a resin layer and a metal layer, and then bonding the outer periphery of the pouch case (114). For example, the battery cell (110) may have a structure in which two electrode leads (111) face each other and protrude from one end (114a) and the other end (114b) of the cell body (113), respectively. As another embodiment, a structure in which all electrode leads (111) of the battery cell (110) protrude in one direction is also possible. One of the electrode leads (111) is a positive electrode lead, and the other is a negative electrode lead.

[0070] The battery cell (110) can be manufactured by bonding the two ends (114a, 114b) of the pouch case (114) and one side (114c) connecting them while the electrode assembly (not shown) is stored in the pouch case (114). In other words, the battery cell (110) according to one embodiment of the present invention has a total of three sealing portions (114s), and the sealing portions (114s) have a structure in which they are sealed by a method such as fusion, and the remaining other side may be formed as a folding portion (115). That is, the battery cell (110) according to the present embodiment can be a pouch-type secondary battery in which the electrode assembly is stored inside the pouch case (114) and the outer periphery of the pouch case (114) is sealed to form the sealing portion (114s). In Fig. 6, only the sealing portions (114s) formed at both ends (114a, 114b) of the pouch case (114) are shown, and the sealing portion is not shown on the side facing the folding portion (115), but the sealing portion of the side facing the folding portion (115) is folded to one side after the sealing is completed for space utilization.

[0071] The pouch case (114) of the laminate sheet may include an inner resin layer for sealing, a metal layer for preventing penetration of materials, and an outermost outer resin layer. Based on the electrode assembly inside the pouch case (114), the inner resin layer may be positioned at the innermost side, the outer resin layer may be positioned at the outermost side, and the metal layer may be positioned between the inner resin layer and the outer resin layer.

[0072] The outer resin layer may have excellent tensile strength and weather resistance relative to its thickness and may exhibit electrical insulation properties to protect the electrode assembly from the outside. The outer resin layer may include polyethylene terephthalate (PET) resin or nylon resin. The metal layer may prevent or suppress air, moisture, etc. from entering the pouch-type secondary battery. The metal layer may include aluminum (Al). The inner resin layers may be thermally bonded to each other by heat and / or pressure applied while the electrode assembly is embedded. The inner resin layer may include cast polypropylene (CPP) or polypropylene (PP).

[0073] A pouch case (114) may be divided into two parts, and a concave receiving portion in which an electrode assembly can be mounted may be formed in at least one of the two parts. Along the outer periphery of the receiving portion, the inner resin layers of the two parts of the pouch case (114) may be bonded to each other to form a sealing portion (114s). In this manner, the pouch case may be sealed, and a battery cell (110), which is a pouch-type secondary battery, may be manufactured.

[0074] The battery modules (100) may be configured with a plurality of battery cells (110). For example, the plurality of battery cells (110) may be stacked along one direction so as to be electrically connected to each other to form a battery cell stack (120). For example, the plurality of battery cells (110) may be stacked along a direction parallel to the X-axis while standing upright. The battery cells (110) may be stacked from one side (210b) to the other side (210b) in a state where one side of the battery cells (110) is parallel to the side surfaces (210b) of the module frame (200) described below. Accordingly, the electrode leads (111) may protrude in a direction perpendicular to the direction in which the battery cells (110) are stacked. In the battery cells (110), one electrode lead (111) may protrude in the Y-axis direction, and the other electrode lead (111) may protrude in the -Y-axis direction. If the battery cell has electrode leads (111) protruding only in one direction, the electrode leads (111) may protrude in the Y-axis direction or the -Y-axis direction.

[0075] Meanwhile, the battery module (100) according to the present embodiment may include a module frame (200) that accommodates battery cells (110). For example, the module frame (200) according to the present embodiment may include a lower frame (210) on which the battery cells (110) are placed and an upper cover (220) that covers the upper portions of the battery cells (110).

[0076] The lower frame (210) and the upper cover (220) are joined by welding or other methods at corresponding corners, so that the module frame (200) can cover the upper part, the lower part, and both sides of the battery cell stack (120). Meanwhile, although not specifically illustrated, a module frame according to another embodiment of the present invention may be a monoframe in which the ceiling part, the bottom part, and both side parts are integrated.

[0077] The lower frame (210) according to the present embodiment may include a bottom portion (210a) and both side portions (210b). The both side portions (210b) may extend upward from opposite sides of the bottom portion (210a) in a direction perpendicular to one side of the bottom portion (210a). The bottom portion (210a) and both side portions (210b) may cover the lower surface and both side surfaces of the battery cell stack (120). As described above, one surface of the battery cells (110) in the battery cell stack (120) is parallel to the side portions (210b) of the lower frame (210), and the battery cells (110) may be stacked along a direction from one side portion (210b) to the other side portion (210b).

[0078] Meanwhile, in the battery module (100) according to the present embodiment, a first end plate (310) and a second end plate (320) may be arranged on one side of the battery cell stack (120) in the direction in which the electrode lead (111) protrudes and on the opposite side, respectively. The first end plate (310) and the second end plate (320) may be joined to the module frame (200) by a method such as welding. The module frame (200), the first end plate (310), and the second end plate (320) may include a metal material to have a predetermined strength. The battery cell stack (120) may be covered by the module frame (200), the first end plate (310), and the second end plate (320) to be protected from external shocks or vibrations.

[0079] Meanwhile, the battery module (100) according to the present embodiment may include a first busbar frame (410) and a second busbar frame (420) that cover one side of the battery cell stack (120) in the direction in which the electrode leads (111) protrude and the opposite side, respectively. The first busbar frame (410) may be positioned between the battery cell stack (120) and the first end plate (310), and the second busbar frame (420) may be positioned between the battery cell stack (120) and the second end plate (320). The first busbar frame (410) and the second busbar frame (420) may include an electrically insulating material, and may prevent or suppress a short circuit from occurring when a busbar (510) or a terminal busbar (520) described below comes into contact with another part of the battery cell (110) other than the electrode leads (111).

[0080] A bus bar (510), a terminal bus bar (520), a module connector (530), etc. may be mounted on each of the first bus bar frame (410) and the second bus bar frame (420). The bus bar (510), the terminal bus bar (520), the module connector (530), etc. may be mounted on the opposite side of the side of the first and second bus bar frames (410, 420) that faces the battery cell stack (120). The bus bar (510) may be electrically connected to the electrode lead (111) of the battery cell (110). For example, the bus bar (510) and the electrode lead (111) may be joined by a welding method. A slit may be formed in the first and second bus bar frames (410, 420), and the electrode lead (111) may pass through the slit and be connected to the bus bar (510). The battery cells (110) can be electrically connected in series or parallel via the bus bar (510).

[0081] The terminal bus bar (520) can be electrically connected to the electrode lead (111), and a portion thereof can be exposed to the outside of the battery module (100). For example, a terminal bus bar opening (321) can be formed in the second end plate (320). A portion of the terminal bus bar (520) can be exposed to the outside of the battery module (100) through the terminal bus bar opening (321). The battery module (100) can form an HV (High voltage) connection with another battery module or electrical equipment through the terminal bus bar (520). Here, the HV connection is a connection that serves as a power source for supplying power requiring high voltage, and refers to a connection between battery cells or a connection between battery modules.

[0082] The module connector (530) is a member for the LV (Low Voltage) connection of the battery module (100). The LV connection refers to an electrical connection that requires a relatively low voltage, such as a battery electrical component. For example, a sensing member (not shown) may sense voltage data of battery cells (110) or temperature data inside the battery module (100), and the module connector (530) connected to the sensing member may transmit the sensed voltage data or temperature data to a BMS (Battery Management System) located outside the battery module (100). Accordingly, a part of the module connector (530) may also be exposed to the outside of the battery module (100). For example, a module connector opening (322) may be formed in the second end plate (320). The module connector (530) may be exposed to the outside of the battery module (100) through the module connector opening (322) and may be connected to an external BMS, etc.

[0083]

[0084] Below, a cooling member according to the present embodiment will be described.

[0085] Figures 7 and 8 are perspective views illustrating battery cells and a cooling member according to one embodiment of the present invention. Figure 9 is a perspective view illustrating a cooling member according to one embodiment of the present invention. Figure 10 is a partial perspective view illustrating the cooling member of Figure 9 from a different angle. Figure 11 is a cross-sectional view taken along the cutting line B-B' of Figure 9.

[0086] Referring to FIGS. 4 to 11 together, the cooling member (600a) according to the present embodiment includes a cooling channel (600C), which is a space in which a coolant flows inside the cooling member (600a), and an air gap (600G), which is an empty space separated from the cooling channel (600C). One surface of the cooling member (600a) may be in contact with one surface of the battery cell (110). That is, the cooling member (600a) may surface-cool the battery cell (110) in a plate-like shape. The coolant may be coolant. The battery module (100) according to the present embodiment may have a water-cooling structure.

[0087] The conventional battery module (10) illustrated in FIGS. 1 and 2 has an edge cooling structure in which heat is discharged through the edge portion of the battery cell (11), whereas the battery module (100) according to the present embodiment may have a surface cooling structure in which a cooling member (600a) having a cooling channel (600C) comes into contact with one surface of the cell body (113) of the battery cells (110). Since one surface of the cell body (113) of the battery cell (110) can come into contact with the cooling member (600a), the cooling area is much wider, and thus there is an advantage of superior cooling performance compared to the conventional battery module (10).

[0088] Within the battery module (100), there is no particular limitation on the number or size of the cooling members (600a), as long as surface cooling of the battery cells (110) can be performed. A plurality of cooling members (600a) may be provided within the battery module (100), and some of the cooling members (600a) may be disposed between the battery cells (110), and other cooling members (600a) may be disposed on both sides of the battery cell stack (120). For example, in FIGS. 7 and 8, three cooling members (600a) are disposed between the battery cells (110), and two cooling members (600a) are each disposed on both sides of the battery cell stack (120). In addition, as another embodiment, the cooling members (600a) may be disposed anywhere between the battery cells (110). The number of cooling members (600a) can be appropriately changed in consideration of the size, capacity, heat generation, etc. of the battery module (100). In addition, there is no particular limitation on the size of the cooling member (600a) as long as it can cover at least 60% of the area of ​​one side of the battery cell (110).

[0089] As described above, the battery cells (110) may experience a swelling phenomenon, in which the electrolyte inside the battery cells decomposes and gas is generated during the repeated charging and discharging process, causing the battery cells (110) to swell. In the swelling phenomenon of the battery cells (110), the battery cells (110) expand in the thickness direction. That is, the battery cells (110) may expand along the direction in which the battery cells (110) are stacked (for example, the direction parallel to the X-axis in FIG. 5). Since the cooling member (600a) according to the present embodiment includes an air gap (600G) therein, the cooling member (600a) can absorb the swelling of the battery cells (110). Conventionally, in order to absorb the swelling of the battery cells (110), a compression pad made of foam material was interposed between the battery cells (110). In the present embodiment, the cooling member (600a) positioned between the battery cells (110) can replace the function of a conventional compression pad by absorbing the swelling of the battery cells (110). That is, the cooling member (600a) according to the present embodiment can perform not only the surface cooling function for the battery cells (110) but also the function of absorbing the swelling of the battery cells (110). Accordingly, deformation of the battery module (100) beyond its deformation limit due to the swelling of the battery cells (110) can be prevented or suppressed.

[0090] Meanwhile, in the case of the conventional battery module (10), since the edges of the battery cells (11) are bonded and fixed to the thermal resin layer (40), when swelling occurs, high stress occurs at the edges of the battery cells (11), which may lead to cracks occurring in the battery cells (11). In the case of the battery module (100) according to the present embodiment, since the cooling member (600a) is arranged between the battery cells (110), the battery cells (110) are not bonded and fixed to a specific point. Even if high swelling occurs in the battery cells (110), a certain degree of structural flexibility can be provided in the stacking direction of the battery cells (110), so that cracks can be prevented or suppressed from occurring in the battery cells (110).

[0091] Meanwhile, as illustrated in FIGS. 8 and 11, the air gap (600G) according to the present embodiment may include a first air gap (600G1) and a second air gap (600G2). The cooling channel (600C) may be positioned between the first air gap (600G1) and the second air gap (600G2). The first air gap (600G1), the cooling channel (600C), and the second air gap (600G2) may be positioned sequentially along the direction in which the battery cells (110) are stacked (the direction parallel to the X-axis, see FIG. 8). In the present embodiment, since the first air gap (600G1) or the second air gap (600G2) may be positioned adjacent to the battery cells (110), swelling of the battery cells (110) may be more effectively absorbed.

[0092] Fig. 12 is a cross-sectional view showing a cooling member according to another embodiment of the present invention.

[0093] Referring to FIG. 12, a cooling member (600b) according to another embodiment of the present invention includes a cooling channel (600C), which is a space in which a coolant flows inside the cooling member (600b), and an air gap (600G), which is an empty space separated from the cooling channel (600C). One surface of the cooling member (600b) can be in contact with one surface of the battery cell (110). That is, the cooling member (600b) can surface-cool the battery cell (110) in a plate-like shape. Similar to the cooling member (600a) described above, the cooling member (600b) according to the present embodiment also includes a cooling channel (600C) and an air gap (600G), and thus can perform a surface-cooling function for the battery cells (110) and a function of absorbing swelling of the battery cells (110).

[0094] Meanwhile, the cooling channel (600C) of the cooling member (600b) according to the present embodiment may include a first cooling channel (600C1) and a second cooling channel (600C2). The air gap (600G) may be positioned between the first cooling channel (600C1) and the second cooling channel (600C2). The first cooling channel (600C1), the air gap (600G), and the second cooling channel (600C2) may be positioned sequentially along the direction in which the battery cells (110) are stacked (the direction parallel to the X-axis, see FIG. 8). In the present embodiment, since the first cooling channel (600C1) or the second cooling channel (600C2) may be positioned adjacent to the battery cells (110), the cooling performance for the battery cells (110) may be further enhanced.

[0095]

[0096] Fig. 13 is a perspective view showing a battery cell stack, a first busbar frame, and a second busbar frame according to one embodiment of the present invention. Figs. 14 and 15 are a perspective view and a front view, respectively, showing a first busbar frame according to one embodiment of the present invention.

[0097] Referring to FIGS. 5, 8 to 11 and 13 to 15 together, as described above, the battery cell (110) according to the present embodiment may include an electrode lead (111), and a busbar frame (410, 420) may be arranged in a direction in which the electrode lead (111) protrudes from the battery cell (110) based on the battery cell stack (120), and a busbar (510) may be mounted on the busbar frame (410, 420). For example, a first busbar frame (410) and a second busbar frame (420) may be arranged on each of both sides of the battery cell stack (120).

[0098] The cooling member (600a) according to the present embodiment may include an inlet port (610) for supplying refrigerant to a cooling channel (600C) and an outlet port (620) for discharging refrigerant from the cooling channel (600C). The inlet port (610) and the outlet port (620) may pass through the first busbar frame (410) and be connected to a pack refrigerant supply pipe and a pack refrigerant discharge pipe, respectively. The pack refrigerant supply pipe and the pack refrigerant discharge pipe will be described later with reference to FIG. 16.

[0099] The inlet port (610) and the outlet port (620) may be tubular members extending from one side of the cooling member (600a), and after the refrigerant flows into the cooling channel (600C) through the inlet port (610), it may be discharged from the cooling channel (600C) through the outlet port (620). That is, the cooling member (600a) may have a refrigerant circulation structure through the inlet port (610) and the outlet port (620).

[0100] An inlet hole (410H1) and an outlet hole (410H2) may be provided in the first busbar frame (410), respectively. The inlet port (610) of the cooling member (600a) may pass through the inlet hole (410H1) of the first busbar frame (410), and the outlet port (620) of the cooling member (600a) may pass through the outlet hole (410H2) of the first busbar frame (410). The inlet port (610) and the outlet port (620) may extend further than the first busbar frame (410) with respect to the battery cell stack (120), and may pass through the inlet hole (410H1) and the outlet hole (410H2), respectively. The inlet port (610) and the outlet port (620) passing through the inlet hole (410H1) and the outlet hole (410H2) respectively can be connected to the pack refrigerant supply pipe and the pack refrigerant discharge pipe described later. The inlet hole (410H1) and the outlet hole (410H2) respectively can be formed in the first busbar frame (410) in the number of cooling members (600a).

[0101] As in the present embodiment, since the inlet port (610) and the outlet port (620) pass through the first busbar frame (410) and extend further than where the first busbar frame (410) is located, the portion where the inlet port (610) is connected to the pack refrigerant supply pipe or the portion where the outlet port (620) is connected to the pack refrigerant discharge pipe can be located to some extent away from electrical connection portions such as electrode leads or busbars. That is, by spaced apart to some extent from the electrical connection portion, the insulation of the cooling member (600a) can be secured.

[0102] In addition, since the inlet port (610) and the outlet port (620) are inserted into the inlet hole (410H1) and the outlet hole (410H2) and pass through the inlet hole (410H1) and the outlet hole (410H2), the inlet port (610) and the outlet port (620) can be fixed in the inlet hole (410H1) and the outlet hole (410H2). Accordingly, the inlet port (610) and the outlet port (620) can be secured against external vibration or impact, and can prevent or suppress refrigerant from leaking from the inlet port (610) or the outlet port (620).

[0103] Meanwhile, referring to FIGS. 4, 5, and 13 to 15 together, as described above, the battery module (100) may include a first end plate (310), and the first busbar frame (410) may be positioned between the first end plate (310) and the battery cell stack (120). An external inlet hole (310H1) and an external outlet hole (310H2) may be formed in the first end plate (310). Each of the external inlet hole (310H1) and the external outlet hole (310H2) may be positioned to correspond to the inlet hole (410H1) and the outlet hole (410H2) of the first busbar frame (410).

[0104] The inlet port (610) passing through the inlet hole (410H1) of the first busbar frame (410) is exposed to the outside of the battery module (100) by passing through the external inlet hole (310H1) of the first end plate (310) and can be connected to the pack coolant supply pipe described later. The outlet port (620) passing through the outlet hole (410H2) of the first busbar frame (410) is exposed to the outside of the battery module (100) by passing through the external outlet hole (310H2) of the first end plate (310) and can be connected to the pack coolant discharge pipe described later.

[0105]

[0106] Hereinafter, a battery pack according to one embodiment of the present invention will be described.

[0107] Fig. 16 is a plan view showing a battery pack according to one embodiment of the present invention.

[0108] Referring to FIGS. 4, 5, and 16 together, a battery pack (1000) according to one embodiment of the present invention includes battery modules (100); a pack frame (1100) that accommodates the battery modules (100); and a pack coolant supply pipe (1200) and a pack coolant discharge pipe (1300) that are connected to a cooling member (600a) and accommodated in the pack frame.

[0109] As described above, the cooling member (600a) may include an inlet port (610) connected to a pack refrigerant supply pipe (1200) and an outlet port (620) connected to a pack refrigerant discharge pipe (1300), and the inlet port (610) and the outlet port (620) may be connected to the pack refrigerant supply pipe (1200) and the pack refrigerant discharge pipe (1300) respectively by passing through the first busbar frame (410). For example, the inlet port (610) passing through the inlet hole (410H1) of the first busbar frame (410) and the external inlet hole (310H1) of the first end plate (310) may be connected to the pack refrigerant supply pipe (1200). In addition, the outlet port (620) passing through the outlet hole (410H2) of the first busbar frame (410) and the external outlet hole (310H2) of the first end plate (310) may be connected to the pack coolant discharge pipe (1300). The pack coolant supply pipe (1200) and the pack coolant discharge pipe (1300) may be connected to a coolant circulation system (not shown) located inside or outside the battery pack (1000). That is, the coolant moving along the pack coolant supply pipe (1200) from the coolant circulation system may be introduced into the cooling channel (600C) through the inlet port (610), and the coolant discharged from the cooling channel (600C) through the outlet port (620) may be returned to the coolant circulation system along the pack coolant discharge pipe (1300). Through the above process, a coolant circulation structure may be implemented within the battery pack (1000).

[0110] The pack frame (1100) according to the present embodiment may include a bottom frame (1110) on which battery modules (100) are placed and a side frame (1120) extending along the edge of the bottom frame (1110). The side frame (1120) may extend in a direction perpendicular to one side of the bottom frame (1110). An internal space having an open upper portion is provided by the bottom frame (1110) and the side frame (1120), and the battery modules (100) may be stored in this internal space. Meanwhile, a pack cover (not shown) may cover the open upper portion of the pack frame (1100).

[0111] The pack coolant supply pipe (1200) and the pack coolant discharge pipe (1300) according to the present embodiment may be arranged in the space between the battery module (100) and the side frame (1120) of the pack frame (1100). In addition, some of the battery modules (100) may be arranged so that the second end plates (320) face each other. As described above, a terminal bus bar opening (321) may be formed in the second end plate (320), and a terminal bus bar (520) may be exposed through the terminal bus bar opening (321). The space between the battery modules (100) where the second end plates (320) face each other may be a space where an HV (High voltage) connection is made by the terminal bus bar (520). That is, HV lines connected to the terminal bus bar (520) may be arranged in the space between the battery modules (100).

[0112] The pack refrigerant supply pipe (1200) and the pack refrigerant discharge pipe (1300) may be arranged in the space between the battery module (100) and the side frame (1120) of the pack frame (1100) to be connected to the inlet port (610) and the outlet port (620) that pass through the external inlet hole (310H1) and the external outlet hole (310H2) of the first end plate (310), respectively.

[0113] Therefore, from the perspective of one battery module (100), the pack coolant supply pipe (1200) and the pack coolant discharge pipe (1300) may be positioned on opposite sides of the HV line. That is, the pack coolant supply pipe (1200) and the pack coolant discharge pipe (1300) may be positioned on the outside of the first end plate (310), and the HV line connected to the terminal bus bar (520) may be positioned on the outside of the second end plate (320).

[0114] By positioning the pack refrigerant supply pipe (1200) and the pack refrigerant discharge pipe (1300) so as to be far from the HV line, problems such as a short circuit caused by the refrigerant leaking from the pack refrigerant supply pipe (1200) and the pack refrigerant discharge pipe (1300) coming into contact with the HV line can be prevented or suppressed. That is, in the battery pack (1000) according to the present embodiment, by spatially separating the pack refrigerant supply pipe (1200) and the pack refrigerant discharge pipe (1300) through which the refrigerant flows from the HV line, insulation performance and safety against refrigerant leakage can be secured.

[0115] 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.

[0116] One or more battery modules 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.

[0117] The above battery module or battery pack can be applied to various devices. For example, it can be applied to transportation vehicles such as electric bicycles, electric vehicles, and hybrid vehicles, or ESS (Energy Storage Systems), but is not limited thereto. It can also be applied to various devices that can use secondary batteries.

[0118] FIG. 17 is a drawing illustrating an automobile (2000) including a battery pack according to an embodiment of the present invention. As illustrated in FIG. 17, a battery pack (1000) according to the present invention may be installed in the automobile (2000). In addition, a battery module (100) according to the present invention may be installed in the automobile (2000). In addition to the battery pack (1000) or the battery module (100), the automobile (2000) according to the present invention may further include various other components included in the automobile (2000). For example, the automobile (2000) according to the present invention may further include a body, a motor, a control device such as an ECU (electronic control unit), etc.

[0119] While the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto. Various modifications and improvements made by those skilled in the art utilizing the basic concepts of the present invention defined in the following claims also fall within the scope of the present invention. Therefore, the technical scope of the various embodiments of the present invention should not be limited to the details set forth in the detailed description of the specification, but should be defined by the scope of the patent claims.

Claims

1. A battery cell stack in which multiple battery cells are stacked; and At least one cooling member disposed on at least one of both sides of the battery cell stack or between the plurality of battery cells; A battery module in which the cooling member includes a cooling channel, which is a space in which a coolant flows inside the cooling member, and an air gap, which is an empty space separated from the cooling channel.

2. In paragraph 1, A battery module in which one surface of the cooling member is in contact with one surface of at least one battery cell among the plurality of battery cells.

3. In paragraph 1, A battery module in which the cooling member is in a plate shape and cools at least one of the plurality of battery cells.

4. In paragraph 1, The above air gap includes a first air gap and a second air gap, A battery module wherein the cooling channel is located between the first air gap and the second air gap.

5. In paragraph 4, A battery module in which the first air gap, the cooling channel, and the second air gap are sequentially positioned along the direction in which the plurality of battery cells are stacked.

6. In paragraph 1, The above cooling channel includes a first cooling channel and a second cooling channel, The above air gap is a battery module located between the first cooling channel and the second cooling channel.

7. In paragraph 6, A battery module in which the first cooling channel, the air gap, and the second cooling channel are sequentially positioned along the direction in which the plurality of battery cells are stacked.

8. In paragraph 1, Each of the plurality of battery cells includes an electrode lead, Based on the above battery cell stack, a bus bar frame is arranged in the direction in which the electrode leads protrude from the plurality of battery cells, A battery module mounted on a busbar frame above.

9. In paragraph 8, The cooling member includes an inlet port for supplying the refrigerant to the cooling channel and an outlet port for discharging the refrigerant from the cooling channel, A battery module in which the above inlet port and the above outlet port pass through the busbar frame and are connected to the pack refrigerant supply pipe and the pack refrigerant discharge pipe, respectively.

10. In paragraph 9, A battery module in which the inlet port and the outlet port extend further than the busbar frame based on the battery cell stack.

11. A plurality of battery modules according to paragraph 1; a pack frame for storing the plurality of battery modules; and A battery pack including a pack coolant supply pipe and a pack coolant discharge pipe connected to the cooling member and housed in the pack frame.

12. In paragraph 11, The cooling member includes an inlet port connected to the pack refrigerant supply pipe and an outlet port connected to the pack refrigerant discharge pipe, The battery pack in which the inlet port and the outlet port are connected to the pack coolant supply pipe and the pack coolant discharge pipe, respectively, by passing through a bus bar frame arranged on one side of the battery cell stack.

13. In paragraph 12, A battery pack in which the pack coolant supply pipe and the pack coolant discharge pipe are arranged in a space between the plurality of battery modules and the side frame of the pack frame.

14. A vehicle including the battery pack according to Article 11.

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