Battery assembly and battery pack including the same

Abstract

A battery assembly according to one embodiment of the present invention comprises: a battery cell unit formed by connecting at least one battery cell to each other in a first direction; a plurality of busbar frame assemblies disposed between the battery cells adjacent in the first direction and at both ends of the battery cell unit; a battery cell stack formed by stacking the battery cell unit in a second direction orthogonal to the first direction; and a cooling spacer extending in the first direction and including one or more flow channels through which a refrigerant flows, wherein the cooling spacer may be disposed between the battery cell units adjacent in the second direction.

Description

Technology Field

[0001] The present invention relates to a battery assembly and a battery pack including the same, and more specifically, to a battery assembly and a battery pack including the same with improved cooling performance and venting performance. Background Technology

[0002] Secondary batteries, which have high applicability across product groups and electrical characteristics such as high energy density, are widely applied not only to portable devices but also to electric vehicles (EVs) or hybrid electric vehicles (HEVs) driven by electric power sources. These secondary batteries are widely used as an energy source for enhancing eco-friendliness and energy efficiency, not only because of the primary advantage of being able to drastically reduce the use of fossil fuels, but also because they do not generate any by-products from energy use.

[0003] Types of secondary batteries include lithium-ion batteries, lithium-polymer batteries, nickel-cadmium batteries, nickel-hydrogen batteries, and nickel-zinc batteries. The operating voltage of these unit secondary battery cells, that is, unit battery cells, is approximately 2.5V to 4.5V. Therefore, if a higher output voltage is required, a battery pack may be formed by connecting multiple battery cells in series. Additionally, a battery pack may be formed by connecting multiple battery cells in parallel depending on the charge / discharge capacity required for the battery pack. Accordingly, the number of battery cells included in the battery pack can be set in various ways depending on the required output voltage or charge / discharge capacity.

[0004] Meanwhile, when configuring a battery pack by connecting multiple battery cells in series or parallel, it is common to first form a battery module by creating a battery cell assembly containing multiple battery cells and housing it in a module case, and then configuring a battery pack by assembling one or more of these battery modules and adding other components, or by arranging multiple battery cells within a pack frame and adding other components.

[0005] Since these battery cells consist of rechargeable secondary batteries, such high-output, high-capacity secondary batteries generate a significant amount of heat during the charging and discharging process. In this case, the heat emitted from multiple battery cells is aggregated within a confined space, causing the temperature to rise rapidly and severely. In other words, while battery packs containing multiple cells can achieve high output, it is not easy to dissipate the heat generated by the cells during charging and discharging. If heat dissipation from the battery cells is not properly carried out, the cells degrade rapidly, shortening their lifespan and increasing the risk of explosion or ignition.

[0006] Furthermore, automotive battery packs are frequently exposed to direct sunlight and may be subjected to high-temperature conditions, such as during the summer or in desert regions. Additionally, because multiple battery cells are densely packed to extend a vehicle's driving range, flames or heat generated in a single battery cell can easily spread to neighboring cells, ultimately leading to the ignition or explosion of the battery pack itself.

[0007] In conventional battery modules, bottom cooling or side cooling methods have been used, in which a heat sink is mounted on the module case of the battery module to cool it.

[0008] However, in the case of battery modules using this cooling method, heat generated from the battery cells is transferred to a heat sink on one side of the module case for cooling, making it difficult to establish a heat transfer path to the other side of the module case. Consequently, there are limitations, such as intensified temperature differences between one end and the other of the battery cell assembly, or unsatisfactory overall cooling efficiency. If these temperature differences are not resolved, issues regarding the safety and durability of the battery module arise. Poor cooling efficiency can accelerate the degradation of battery cells or lead to the spread of thermal runaway if a rapid response is not possible when it occurs in some cells. This can result in disasters such as ignition and explosion of the battery module or the battery pack containing it, causing not only property damage but also safety issues.

[0009] To solve this problem, it has been proposed to use a method of directly cooling the battery cells by filling the inside of the battery assembly with coolant or cooling oil, rather than relying on bottom cooling or side cooling. In other words, to effectively cool high-capacity battery assemblies, a method is used in which a refrigerant directly cools the battery cells inside the battery assembly.

[0010] Recently, there has been a requirement to increase the number of battery cells included in a battery assembly to secure capacity. As the number of battery cells increases, the battery assembly becomes larger; however, as the battery assembly becomes larger, it becomes difficult to circulate the refrigerant, which can lead to a decrease in cooling efficiency and difficulties in forming a venting path due to the circulation of the refrigerant. Accordingly, there is a need to develop a battery assembly with improved cooling efficiency and improved venting performance in a structure where the refrigerant directly cools the battery cells and the venting gas is discharged. The problem to be solved

[0011] The problem to be solved by the present invention is to provide a battery assembly with improved cooling performance and venting performance and a battery pack including the same, in a cooling structure in which a refrigerant cools battery cells and a structure in which venting gas is discharged.

[0012] However, the problems that the embodiments of the present invention aim to solve 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. means of solving the problem

[0013] A battery assembly according to one embodiment of the present invention comprises: a battery cell unit formed by connecting at least one battery cell to each other in a first direction; a plurality of busbar frame assemblies disposed between the battery cells adjacent in the first direction and at both ends of the battery cell unit; a battery cell stack formed by stacking the battery cell unit in a second direction orthogonal to the first direction; and a cooling spacer extending in the first direction and including one or more flow channels through which a refrigerant flows, wherein the cooling spacer may be disposed between the battery cell units adjacent in the second direction.

[0014] The above busbar frame assembly includes a busbar that electrically connects the electrode leads of at least one battery cell and a busbar frame on which the busbar is disposed on one surface, and the busbar frame may include an opening formed through from the one surface to the other surface opposite to the one surface.

[0015] The above busbar frame may further include a busbar mounting portion formed by being recessed from the above one surface, on which the busbar is positioned.

[0016] The above cooling spacer further includes an opening formed at a position corresponding to the location where the opening is formed, and the refrigerant can come into direct contact with the busbar as it flows out from the cooling spacer through the opening and flows into the interior of the busbar frame through the opening.

[0017] The battery cell unit comprises a first battery cell unit in which the electrode lead of each of the at least one battery cell is connected to the bus bar in the same direction with respect to the second direction, and a second battery cell unit in which the electrode lead of the first battery cell unit is connected to the bus bar in the opposite direction to the direction in which the electrode lead of the first battery cell unit is connected to the bus bar, and the cooling spacer disposed between the first battery cell unit and the second battery cell unit can form a battery cell unit assembly.

[0018] The above busbar frame further includes a spacer insertion portion formed by being recessed from the other side opposite to the one side, and a stepped portion formed on the other side as the spacer insertion portion is recessed, and when the cooling spacer is inserted into the spacer insertion portion, a part of the cooling spacer can be caught on the stepped portion and fixed.

[0019] The above busbar frame assembly includes a first busbar frame assembly connected to the first battery cell unit and a second busbar frame assembly connected to the second battery cell unit, and the busbar frame of the first busbar frame assembly and the busbar frame of the second busbar frame assembly can be joined such that their respective stepped portions come into contact with each other on the other surface.

[0020] The battery assembly further includes a pad member disposed between the battery cell unit assemblies, and the pad member may be wrapped with a sheet capable of electrical insulation and moisture prevention.

[0021] The above sheet may include aluminum.

[0022] The battery assembly further includes a busbar sensing unit that senses and transmits at least one of the voltage and temperature of the busbar, and each of the busbar frame assemblies disposed in each battery cell unit of the battery cell stack can be connected in the second direction by the busbar sensing unit.

[0023] The battery assembly further includes end covers that cover both ends of the battery cell stack with respect to the first direction, and the end covers may include spacer through holes through which the cooling spacer passes and is fixed.

[0024] The battery assembly may further include a filler member disposed in the space between the end cover and the battery cell stack.

[0025] The above end cover further includes an injection hole into which the filler member is injected, and the filler member can be injected into the space between the end cover and the battery cell stack through the injection hole.

[0026] The injection hole can be formed between the spacer through holes.

[0027] The above filler member may be additionally disposed in the space between the battery cell and the busbar frame assembly.

[0028] The above filler member may include an expandable member that expands at a temperature above a predetermined temperature.

[0029] On the upper surface of the battery cell stack, an adhesive is applied to an adhesive application area extending in the second direction, and the adhesive application area is formed in multiple units spaced apart in the first direction, and a venting area in which a venting gas moves can be formed between the multiple adhesive application areas.

[0030] The above plurality of adhesive application areas can be formed at both ends of the battery cell.

[0031] A battery pack according to one embodiment of the present invention may include the aforementioned battery assembly.

[0032] The above battery assembly is provided in multiple numbers, and the multiple battery assemblies are separated by a partition member, and the refrigerant can pass through the partition member and flow to an adjacent battery assembly. Effects of the invention

[0033] According to embodiments of the present invention, a cooling spacer is placed between battery cells in a battery assembly structured to house battery cells and circulate a refrigerant, thereby establishing a cooling circulation path and improving cooling efficiency and cooling performance. Additionally, the cooling spacer can maintain the structure of the enlarged battery assembly while simultaneously reinforcing structural rigidity along the stacking direction of the battery cell units.

[0034] In addition, by providing a venting region that forms a path for the movement of venting gas through the application of an adhesive, the cooling of the battery cell is achieved by the flow of refrigerant through the cooling spacer, and the movement of venting gas can occur only through the venting region. Accordingly, the flow of refrigerant and the movement of venting gas can be separated, and since the movement of venting gas is separated from and unaffected by the flow of refrigerant, it can be effective in smoothly discharging venting gas to the outside of the battery pack even if venting gas is generated in the battery assembly.

[0035] The effects of the present invention are not limited to those mentioned above, and other unmentioned effects will be clearly understood by those skilled in the art from the description in the claims. Brief explanation of the drawing

[0036] The following drawings attached to this specification illustrate embodiments of the present invention and serve to further enhance understanding of the technical concept of the present invention together with the description of the invention provided below; therefore, the present invention should not be interpreted as being limited only to the matters described in such drawings. FIG. 1 is an exploded perspective view showing a battery assembly according to one embodiment of the present invention. FIG. 2 is a perspective view showing a battery cell according to one embodiment of the present invention. Figure 3 is a plan view of the battery cell shown in Figure 2. FIG. 4 is a perspective view showing a cooling spacer and a busbar frame assembly included in the battery assembly shown in FIG. 1. Figure 5 is an enlarged perspective view of part A of Figure 4. Figure 6 is a cross-sectional view showing a cross-section cut along the cutting line B-B' of Figure 5. FIG. 7 is an exploded perspective view illustrating the assembly of the busbar frame assembly shown in FIG. 5. FIG. 8 is a front view, a perspective view, and a rear perspective view of a busbar frame assembly according to one embodiment of the present invention. FIG. 9 is a perspective view showing a battery cell unit assembly according to one embodiment of the present invention. FIG. 10 is a perspective view showing a pad member placed in the battery cell unit assembly of FIG. 9. FIG. 11 is a front view showing an end cover and a cooling spacer assembled on the end cover according to one embodiment of the present invention. FIG. 12 is a top view showing the arrangement of a filler member in a battery assembly according to one embodiment of the present invention. FIG. 13 is a cross-sectional view showing the path of refrigerant flow in a battery assembly according to one embodiment of the present invention. FIG. 14 is a top view showing the arrangement of a busbar sensing unit in a battery assembly according to one embodiment of the present invention. FIG. 15 is a perspective view of a battery pack according to one embodiment of the present invention. FIG. 16 is an exploded perspective view of the battery pack shown in FIG. 15. FIG. 17 is a top view showing a schematic path of refrigerant flow in a battery pack according to one embodiment of the present invention. FIG. 18 is a top view showing a battery assembly arranged in a battery pack according to one embodiment of the present invention. FIG. 19 is a top view showing an adhesive arranged in a battery pack according to one embodiment of the present invention. FIG. 20 is a cross-sectional view schematically showing a venting path in a battery pack according to one embodiment of the present invention. Specific details for implementing the invention

[0037] 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 present invention. The present invention may be embodied in various different forms and is not limited to the embodiments described herein.

[0038] To clearly explain the present invention, parts unrelated to the explanation have been omitted, and the same reference numerals are used for identical or similar components throughout the specification.

[0039] Furthermore, the size and thickness of each component shown in the drawings are depicted arbitrarily for convenience of explanation, and thus the present invention is not necessarily limited to what is illustrated. Thicknesses have been enlarged in the drawings to clearly represent various layers and regions. Additionally, for convenience of explanation, the thickness of some layers and regions has been exaggerated in the drawings.

[0040] Furthermore, when a part such as a layer, membrane, region, or plate is said to be "on" or "on" another part, this includes not only the case where it is "directly above" the other part, but also the case where there is another part in between. Conversely, when a part is said to be "directly above" another part, it means that there is no other part in between. Also, saying that a part is "on" or "on" a reference part means that it is located above or below the reference part, and does not necessarily mean that it is located "on" or "on" facing the opposite direction of gravity.

[0041] In addition, terms indicating directions such as front, back, left, right, up, and down have been used; however, these terms are merely for the convenience of explanation and may vary depending on the location of the object or the observer.

[0042] Furthermore, throughout the specification, when a part is described as "including" a certain component, this means that, unless specifically stated otherwise, it does not exclude other components but may include additional components.

[0043] Additionally, throughout the specification, "planar" means when the subject part is viewed from above, and "cross-sectional" means when the cross-section obtained by vertically cutting the subject part is viewed from the side.

[0044] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0045] FIG. 1 is an exploded perspective view showing a battery assembly according to one embodiment of the present invention. FIG. 2 is a perspective view showing a battery cell according to one embodiment of the present invention. FIG. 3 is a plan view of the battery cell shown in FIG. 2.

[0046] Referring to FIGS. 1 to 3, a battery assembly (100) according to one embodiment of the present invention comprises a battery cell unit (100U) formed by connecting at least one battery cell (110) to each other in a first direction, a plurality of busbar frame assemblies (130) disposed between adjacent battery cells (110) in the first direction and at both ends of the battery cell unit (100U), a battery cell stack (120) formed by stacking battery cell units (100U) in a second direction orthogonal to the first direction, and a cooling spacer (140) extending in the first direction and including one or more flow channels (141) through which a refrigerant (CL) flows, and the cooling spacer (140) may be disposed between adjacent battery cell units (100U) in the second direction.

[0047] Hereinafter, the battery cell (110) according to the present embodiment will be described in detail. The battery cell (110) according to the present embodiment can be any type of secondary battery, such as a prismatic, cylindrical, or pouch-type battery cell. However, below, as an example, the battery cell (110) which is a pouch-type battery cell will be described.

[0048] First, the battery cell (110) may be a pouch-type battery in which an electrode assembly having electrode leads (111) protruding in one or both directions is housed in a pouch case (114). However, this is merely one example, and the battery cell according to another embodiment of the present invention may be a cylindrical or prismatic battery cell. For convenience of explanation, the following description will be based on a pouch-type battery cell (110).

[0049] The battery cell (110) may have a rectangular sheet shape. The battery cell (110) may be formed by housing an electrode assembly in a pouch case (114) of a laminate sheet comprising 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) protrude from one end and the other end of the cell body (113) facing each other. 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. The electrode leads (111) may include a metal material as they are configured to guide the electrical connection of the battery cell (110). For example, the electrode leads (111) may include an aluminum material.

[0050] The battery cell (110) may have a sealing portion, which is a portion that is bonded to the outer periphery of the pouch case (114). Specifically, the battery cell (110) may be manufactured by bonding the two ends (114c, 114d) of the pouch case (114) and the upper portion (114b) connecting them, while the electrode assembly (not shown) is housed in the pouch case (114). Sealing portions may be formed on the two ends (114c, 114d) and the upper portion (114b) of the pouch case (114). In other words, the battery cell (110) according to the present embodiment has a total of three sealing portions, and the sealing portions are structured to be sealed by a method such as fusion, and the remaining lower portion (114a) may be made of a folding portion. That is, the battery cell (110) according to the present embodiment may be a pouch-type battery cell in which an electrode assembly is housed inside a pouch case (114) and the outer periphery of the pouch case (114) is sealed to form a sealing portion. In FIG. 2, only the sealing portions formed at both ends (114c, 114d) of the pouch case (114) are shown, and the upper portion (114b) is shown in a state where the sealing portion is folded to one side after the sealing is completed.

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

[0052] The outer resin layer may possess excellent tensile strength and weather resistance relative to its thickness and electrical insulation properties to protect the electrode assembly from the outside. This outer resin layer may include polyethylene terephthalate (PET) resin or nylon resin. The metal layer may prevent air, moisture, etc. from entering the interior of the pouch-type secondary battery. This metal layer may include aluminum (Al). The inner resin layers may be thermally fused together by applied heat and / or pressure while the electrode assembly is embedded. This inner resin layer may include casted polypropylene (CPP) or polypropylene (PP).

[0053] A pouch case (114) may be divided into two parts, and a concave-shaped storage portion may be formed in at least one of the two parts so that an electrode assembly can be seated thereon. Along the outer circumference of this storage portion, a sealing portion may be provided by bonding the inner resin layers of the two parts of the pouch case (114) to each other. In this way, the pouch case (114) is sealed so that a battery cell (110), which is a pouch-type battery, can be manufactured.

[0054] Meanwhile, the sealing portions at both ends (114c, 114d) of the battery cell (110), where the electrode lead (111) protrudes from the battery cell (110), correspond to the so-called terrace part of the battery cell (110). This terrace part is thinner than the cell body (113) of the battery cell (110).

[0055] At least one battery cell (110) may be connected to one another in a first direction to form a battery cell unit (100U), and a plurality of battery cell units (100U) may be stacked in a second direction orthogonal to the first direction to form a battery cell stack (120). The battery cells (110) in the battery cell unit (100U) and the battery cell stack (120) may be electrically connected to one another. In particular, as shown in FIG. 1, a plurality of battery cells (110) of the battery cell unit (100U) may be arranged side by side along the first direction. Additionally, a plurality of battery cell units (100U) may be stacked along the second direction while standing upright so that each battery cell (110) faces one side of the cell body (113). As described above, in the present invention, the first direction may be a direction parallel to the y-axis, and the second direction may be a direction parallel to the x-axis. Accordingly, the electrode leads (111) can protrude in a direction perpendicular to the direction in which the battery cells (110) are stacked. The electrode leads (111) can protrude along a direction parallel to the first direction. That is, in the battery cell (110), one electrode lead (111) can protrude toward the y-axis direction, and the other electrode lead (111) can protrude toward the -y-axis direction. Thus, in the battery cell unit (100U), the electrode leads (111) of adjacent battery cells (110) can be connected to each other.

[0056] As illustrated in FIG. 1, a battery assembly (100) according to an embodiment of the present invention may include a frame (180) that accommodates a battery cell stack (120) and end covers (190) that cover both sides of the battery cell stack (120) with respect to a first direction. Here, the two sides of the battery cell stack (120) refer to the two sides of the battery cell stack (120) according to the direction in which electrode leads (111) protrude from the battery cell (110). In other words, the battery assembly (100) according to the present embodiment may include a frame (180) in which one side in the direction in which the electrode leads (111) protrude from the battery cell stack (120) is open, and an end cover (190) that covers the open side of the frame (180). For example, as illustrated in FIG. 1, the frame (180) can be opened in both directions in the Y-axis direction and the -Y-axis direction in which the electrode lead (111) protrudes, and two end covers (190) can each cover the two open directions of the frame (180).

[0057] The frame (180) may be intended to protect the battery cell stack (120) and the electrical components connected thereto from external physical impact. The battery cell stack (120) and the electrical components connected thereto may be accommodated in the internal space of the frame (180).

[0058] As illustrated in FIG. 1, the frame (180) may include an upper plate (182) disposed on the upper surface of the battery cell stack (120) with respect to a third direction that is orthogonal to the first direction and the second direction, respectively. In this case, the third direction is a direction parallel to the z-axis, and the upper direction may be the z-axis direction. Meanwhile, for convenience of explanation, the first direction may be referred to as the front-back direction, the second direction as the side direction, and the third direction as the up-down direction.

[0059] The frame (180) may be in a form with the front and rear sides open, and the top surface, bottom surface, and both sides covered. For example, the frame (180) may include a U-shaped lower frame (181) with the top surface, front surface, and rear surface open, and an upper plate (182) that covers the top surface of the battery cell stack (120). However, the structure of the frame (180) is not limited to the above description and may be replaced with a frame of other shapes, such as an L-shaped frame or a monoframe that surrounds the battery cell stack (120) excluding the front and rear surfaces. That is, the frame (180) may be formed as a single frame (180) that is not separated into a U-shaped lower frame (181) and an upper plate (182).

[0060] Meanwhile, the detailed configuration of the battery cell stack (120) and the end cover (190) will be described with reference to the following drawings.

[0061] FIG. 4 is a perspective view showing a cooling spacer and a busbar frame assembly included in the battery assembly illustrated in FIG. 1. FIG. 5 is an enlarged perspective view of section A in FIG. 4. FIG. 6 is a cross-sectional view showing a section cut along the cutting line B-B' in FIG. 5. FIG. 7 is an exploded perspective view illustrating the assembly of the busbar frame assembly illustrated in FIG. 5. FIG. 8 is a front view, a perspective view, and a rear perspective view of a busbar frame assembly according to an embodiment of the present invention. FIG. 9 is a perspective view showing a battery cell unit assembly according to an embodiment of the present invention.

[0062] Referring to FIGS. 4 through 9, a busbar frame assembly (130) may be disposed between adjacent battery cells (110) in a first direction and at both ends of a battery cell unit (100U). The busbar frame assemblies (130) may electrically connect the battery cells (110) of a battery cell stack (120).

[0063] The busbar frame assembly (130) may include a busbar (131) that electrically connects the electrode leads (111) of at least one battery cell (110) and a busbar frame (132) on which the busbar (131) is disposed.

[0064] The busbar (131) is a component for electrically connecting a plurality of battery cells (110) and is made of a metallic material with excellent electrical conductivity. For example, the busbar (152) may include any one selected from copper, iron, aluminum, and alloys thereof. According to the present embodiment, the electrode lead (111) connected to the electrode assembly protrudes outside the pouch case (114), and the electrode leads (111) of each battery cell (110) can be electrically connected to each other via the busbar (131). For example, the busbar (131) can be connected to the electrode lead (111) through welding. Meanwhile, the material of the busbar (131) is not limited to what is described above and can be modified or changed in various ways depending on the environment in which the present invention is implemented.

[0065] A busbar (131) may be mounted on the busbar frame (132). The busbar frame (132) may be a component to prevent a short circuit from occurring when the electrode lead (111) and the busbar (131) come into contact with other parts of the battery cell (110). To this end, the busbar frame (132) may include a material that is electrically insulating. The material of the busbar frame (132) may be made of a material used for conventional busbar frames, and a detailed description thereof will be omitted.

[0066] The busbar frame (132) may include a busbar mounting portion (134) formed by being recessed from one side, on which a busbar (131) is disposed. The busbar (131) may be disposed on the busbar mounting portion (134) and mounted on the busbar frame (132). At this time, the busbar (131) and the busbar frame (132) may be joined together, and there are no restrictions on the joining method. For example, the busbar (131) and the busbar frame (132) may be joined using a joining method utilizing physical restraints such as bolting, hook fastening, or interference fit, and may be modified or changed in various ways depending on the environment in which the present invention is implemented.

[0067] The cooling spacer (140) may be a plate-shaped member extending in a first direction. The cooling spacer (140) may be positioned between adjacent battery cell units (100U) in a second direction. Accordingly, one side of the cooling spacer (140) may come into contact with one side of the cell body (113) of the battery cell (110). That is, the cooling spacer (140) may be positioned between the battery cell units (100U) while in surface contact with the battery cell (110). Meanwhile, an adhesive may be interposed between the cooling spacer (140) and the battery cell (110) so that the cooling spacer (140) can be fixed to the battery cell (110). However, the method of fixing the cooling spacer (140) is not limited to what is described above and may be modified or changed in various ways depending on the environment in which the present invention is implemented.

[0068] The cooling spacer (140) may include one or more flow channels (141) through which a refrigerant flows. The flow channels (141) are formed to extend through the cooling spacer (140) along a first direction in which the cooling spacer (140) extends. In the example illustrated in FIGS. 5 to 7, the flow channels (141) may be formed in multiple numbers along a third direction that is orthogonal to the first direction and the second direction, respectively. Meanwhile, the number of flow channels (141) formed in the cooling spacer (140) is not limited by the illustrated form. For example, only one flow channel (141) may be formed in the cooling spacer (140). The number and shape of such flow channels (141) may be varied or changed in various ways depending on the environment in which the present invention is implemented.

[0069] Meanwhile, the refrigerant according to the present embodiment is a cooling medium that cools a heat-generating object, and there are no restrictions on its form or material. Refrigerants of various phases may be applied. For example, a cooling medium in a solid, fluid, liquid, or gaseous state may be applied to the refrigerant without limitation. In addition, bubbles, paraffin, or phase change materials (PCM) may be applied to the refrigerant.

[0070] As an example, the refrigerant may be a fluid. The refrigerant may be cooling water or cooling oil. Meanwhile, since the refrigerant may come into direct contact with the battery cells (110), electrode leads (111), and busbar (131), etc. within the battery assembly (100), the refrigerant may be electrically insulating. The refrigerant may be a material having insulating properties. For example, the refrigerant may be insulating oil. However, these are exemplary materials, and as described above, any material capable of cooling an object requiring cooling may be applied to the refrigerant in the present invention without limitation.

[0071] Gas may be generated inside the battery cell (110) due to deterioration or other factors as charging and discharging are repeated. When gas is generated inside in this way, the internal pressure increases, causing a swelling phenomenon in which the battery cell (110) bulges. In particular, in the case of a pouch-type battery cell, the structural rigidity of the outer material is weaker compared to a can-type battery cell, so the swelling phenomenon may occur more prominently. Battery cells (110) that have undergone swelling may expand mainly along their thickness direction. In the case of the battery cells (110) according to the present embodiment, they may expand along the second direction, that is, the direction parallel to the x-axis, which is the direction in which the battery cells (110) and / or battery cell units (100U) are stacked.

[0072] Additionally, when the battery cell stack (120) is compressed along a direction parallel to the x-axis, the battery cell stack (120) can be housed inside the frame (180). This may be one of the methods for applying a certain level of pressure to the battery cells (110). The pressure applied to the battery cells (110) may affect the lifespan performance of the battery assembly (100). An appropriate level of pressure must be applied to the battery cells (110) so that the appropriate capacity can be maintained even when the charge and discharge cycles of the battery assembly (100) proceed. If the pressure is below or above a certain level, a problem of sudden drop in capacity may occur during the cycle.

[0073] The second direction, which is the direction in which the battery cells (110) and / or battery cell units (100U) are stacked, may also be the direction in which the battery cells (110) expand due to swelling, and may also be the direction in which a compressive force is applied to the battery cell stack (120) to apply an appropriate level of pressure to the battery cells (110). Accordingly, within the frame (180), one side of the battery cells (110) according to the direction in which the battery cells (110) and / or battery cell units (100U) are stacked may be a place where the influence of the refrigerant is minimal.

[0074] As described above, due to expansion caused by swelling of the battery cells (110) or pressure applied in the second direction to the battery cell stack (120), it is difficult to provide sufficient space between the battery cells (110) stacked along the second direction, and the battery cells (110) or the pad member (150) described later may be in close contact with each other. Therefore, it is difficult for the refrigerant to flow between the battery cells (110). Accordingly, in this embodiment, by placing a cooling spacer (140) between the battery cells (110), a space for the refrigerant to flow between the battery cells (110) can be secured. As the refrigerant flows along the flow channel (141) of the cooling spacer (140), the cooling spacer (140) can cool the battery cells (110). Specifically, the cooling spacer (140) can cool the battery cells (110) by contacting one side of the battery cells (110) directly or indirectly.

[0075] Surface cooling for the battery cells (110) can be achieved by a refrigerant flowing along the flow channel (141) of the cooling spacer (140). Additionally, cooling for the electrode leads (111) of the battery cells (110) and the busbar (131) can be achieved by the structure of the opening (133) of the busbar frame (132) and the opening (142) of the cooling spacer (140), the details of which will be described later.

[0076] The busbar frame (132) may include an opening (133) formed through from one side where the busbar (131) is positioned to the other side opposite to said side. Additionally, the cooling spacer (140) may include an opening (142) formed at a position corresponding to the location where the opening (133) of the busbar frame (132) is formed.

[0077] The opening (142) may be formed such that one side and the other side of the cooling spacer (140) are each opened to the outside. For example, the opening (142) may be formed to penetrate from one side of the cooling spacer (140) to the other side. The refrigerant (CL) may be discharged from the cooling spacer (140) through the opening (142) of the cooling spacer (140). Specifically, at least a portion of the flow channels (141) inside the cooling spacer (140) is exposed to the outside of the cooling spacer (140) by the opening (142), and the refrigerant flowing through each flow channel (141) may be discharged from the cooling spacer (140) through the opening (142).

[0078] At this time, since the opening (142) of the cooling spacer (140) is formed at a position corresponding to the location where the opening (133) of the busbar frame (132) is formed, the refrigerant flowing out from the cooling spacer (140) through the opening (142) can flow into the interior of the busbar frame (132) through the opening (133). As shown in the example illustrated in FIG. 7, since the opening (133) of the busbar frame (132) is formed to penetrate from one side where the busbar (131) is placed to the other side, the refrigerant (CL) flowing in from the other side of the busbar frame (132) can come into direct contact with the busbar (131) placed on one side of the busbar frame (132).

[0079] Generally, since a large amount of heat is generated on the busbar (131) and the electrode lead (111) in contact with the busbar (131), it is necessary to effectively cool them. In the present embodiment, as described above, the cooling performance on the busbar (131) can be improved by the refrigerant coming into direct contact with the busbar (131). Furthermore, in the present embodiment, without the need to secure a separate cooling channel for cooling the electrode lead (111) and the busbar (131) of the battery cells (110), the cooling of the electrode lead (111) and the busbar (131) of the battery cells (110) can be achieved by the structure of the opening (133) of the busbar frame (132) and the opening (142) of the cooling spacer (140). Therefore, since the present embodiment can secure a cooling channel space sufficient to achieve the desired cooling performance within the limited space inside the frame (180), it can be seen that the space utilization inside the frame is increased.

[0080] Referring to FIGS. 6 to 8, the busbar frame (132) may include a spacer insertion portion (135) formed by being recessed from the opposite side opposite to one side, and a step portion (136) formed on the opposite side as the spacer insertion portion (135) is recessed. At this time, when a cooling spacer (140) is inserted into the spacer insertion portion (135), a part of the cooling spacer (140) may be caught on the step portion (136) and fixed. Through such a structure, the busbar frame (132) and the cooling spacer (140) can be more stably coupled to each other.

[0081] As illustrated in the example in FIG. 9, the battery cell unit (100U) of the present embodiment may include a first battery cell unit (100U) in which the electrode lead (111) of each of at least one battery cell (110) is connected to a bus bar (131) in the same direction with respect to the second direction, and a second battery cell unit (100U) in which the electrode lead (111) of the first battery cell unit (100U) is connected to a bus bar (131) in the opposite direction to the direction in which the electrode lead (111) of the first battery cell unit (100U) is connected to the bus bar (131).

[0082] At this time, the first battery cell unit (100U), the second battery cell unit (100U), and the cooling spacer (140) disposed between the first battery cell unit (100U) and the second battery cell unit (100U) can form a battery cell unit assembly (100UA). For example, the battery cell unit assembly (100UA) may be in a form where the first battery cell unit (100U) and the second battery cell unit (100U) are symmetrically arranged with respect to each other with the cooling spacer (140) in between.

[0083] Additionally, the busbar frame assembly (130) includes a first busbar frame assembly (130) connected to a first battery cell unit (100U) and a second busbar frame assembly (130) connected to a second battery cell unit (100U), and the busbar frame (132) of the first busbar frame assembly (130) and the busbar frame (132) of the second busbar frame assembly (130) can be joined such that their respective stepped portions (136) come into contact with each other on opposite sides.

[0084] In this embodiment, there are no restrictions on the method by which the first busbar frame assembly (130) and the second busbar frame assembly (130) are joined to each other, and both methods of joining using physical restraints such as bolting or hook fastening, or joining by adhesive, may be applied.

[0085] As illustrated in the example in FIG. 9, in the battery cell unit assembly (100UA), the busbar frame assembly (130) connecting the battery cell unit (100U) and the battery cell (110) may be in a form where the first battery cell unit (100U) and the first busbar frame assembly (130) and the second battery cell unit (100U) and the second busbar frame assembly (130) are symmetrically arranged with respect to each other with a cooling spacer (140) in between.

[0086] FIG. 10 is a perspective view showing a pad member placed in the battery cell unit assembly of FIG. 9.

[0087] Referring again to FIGS. 1 and FIGS. 10, the battery assembly (100) may include a pad member (150) disposed between battery cell unit assemblies (100UA). For example, the pad member (150) may be disposed on both sides of the battery cell unit assembly (100UA). More specifically, the pad member (150) may be disposed on the outermost side of the battery cell stack (120) with respect to the second direction, and may be disposed between the battery cell unit assemblies (100UA) in the battery cell stack (120).

[0088] The pad member (150) may be a foam-shaped member and can absorb swelling of the battery cells (110). If the swelling phenomenon of the battery cells (110) is not absorbed and controlled, the pressure inside the battery assembly (100) increases and the volume increases, which may have a negative effect on the structural stability of the battery assembly (100). Accordingly, by placing a pad member (150) that is compressed when pressure is applied at the outermost side of the battery cell stack (120) according to the second direction or between the battery cell unit assemblies (100UA), it is possible to absorb at least a portion of the swelling of the battery cells (110). The pad member (150) may include a polyurethane material, for example, but the material is not limited to that described above. That is, as long as the pad member (150) can be compressed to absorb swelling of the battery cell (110), there are no special restrictions on the material, and it can be modified or changed in various ways depending on the environment in which the present invention is implemented.

[0089] The pad member (150) can be wrapped with a sheet capable of electrical insulation and moisture prevention. Since the pad member (150) can come into contact with the busbar (131) and additionally with the refrigerant, it can be wrapped with a sheet capable of electrical insulation and moisture prevention to prevent electrical conduction with the busbar (131) and to prevent moisture absorption of the refrigerant by the pad member (150).

[0090] The above sheet may include aluminum, for example, the sheet may include an aluminum oxide (Al2O3) layer formed by oxidizing the surface, or an insulating coating layer on the aluminum sheet. However, the material of the sheet is not limited as described above. That is, the sheet wrapped on the pad member (150) has no particular limitation on its material as long as it is capable of electrical insulation and moisture prevention, and can be modified or changed in various ways depending on the environment in which the present invention is implemented.

[0091] FIG. 11 is a front view showing an end cover and a cooling spacer assembled to the end cover according to an embodiment of the present invention. FIG. 12 is a top view showing a filler member arranged in a battery assembly according to an embodiment of the present invention. FIG. 13 is a cross-sectional view showing a path through which a refrigerant flows in a battery assembly according to an embodiment of the present invention.

[0092] Referring to FIGS. 11 through 13, the end cover (190) covers an open side of the frame (180). For example, the end covers (190) may be positioned on the front and rear of the battery cell stack (120) to cover both ends of the battery cell stack (120). Specifically, the end covers (190) may be positioned on the outside of the busbar frame assembly (130) which is placed at both ends of the battery cell unit (100U) relative to the battery cell stack (120). Accordingly, the end covers (190) may cover the battery cell stack (120) and the busbar frame assembly (130). As the frame (180) is covered by the end cover (190), the internal space of the frame (180) may be sealed. The end cover (190) may prevent the refrigerant from leaking to the outside of the frame (180). There are no special restrictions on the material applied to the end cover (190), but for example, the end cover (190) may include a plastic material or a metal material.

[0093] For example, the end cover (190) may include a spacer through hole (191) through which a cooling spacer (140) is passed and fixed. Since the cooling spacer (140) is passed into the interior of the frame (180) through the spacer through hole (191) of the end cover (190), a refrigerant can be circulated into the interior of the frame (180) through the cooling spacer (140). Additionally, as the cooling spacer (140) is passed through and fixed to the end cover (190) and is positioned between the battery cell units (100U), structural stability and rigidity against external impact of the battery cell stack (120) can be secured, and a flow path for the refrigerant (CL) can be provided to maximize the cooling effect of the battery cells (110).

[0094] The end cover (190) may further include an injection hole (192) into which a filler member (170) is injected. In this case, the injection hole (192) may be formed between the spacer through holes (191). The filler member (170) may be injected into the space between the end cover (190) and the battery cell stack (120) through the injection hole (192). Meanwhile, the formation location and shape of the injection hole (192) illustrated in FIG. 11 are not limited to the illustrated shape and the above description. That is, as long as the filler member (170) can be effectively injected, the formation location and shape of the injection hole (192), etc., may be varied or changed in various ways depending on the environment in which the present invention is implemented.

[0095] The filler member (170) may include an expandable member that expands above a predetermined temperature. The expandable member may be a member that can expand in volume by foaming at a predetermined temperature. The expandable member may expand in volume to prevent the propagation of venting gas, etc., generated from the battery cell (110) where a thermal event or thermal runaway occurs in the battery cell (110).

[0096] The expandable member may include materials corresponding to foamed polymers, for example, at least one of silica gel, foamed silicone, polystyrene, polyurethane, polyethylene, and polypropylene. Meanwhile, the material of the expandable member is not limited to what is described above and may include various foamed materials having high-temperature durability, electrical insulation properties, etc.

[0097] A filler member (170) including an expandable member may be placed inside the battery assembly (100) to prevent venting gas, etc., generated from a battery cell (110) where a thermal event or thermal runaway has occurred from propagating along an unintended path. In one example, the filler member (170) may be injected into the space between the end cover (190) and the battery cell stack (120) through an injection hole (192). In another example, the filler member (170) may be injected into the space between the battery cell (110) and the busbar frame assembly (130) through the side of the battery cell stack (120).

[0098] That is, the filler member (170) may include a first filler member (170) disposed in the space between the end cover (190) and the battery cell stack (120), and a second filler member (170) additionally disposed in the space between the battery cell (110) and the busbar frame assembly (130). In this case, the first filler member (170) and the second filler member (170) are referred to differently merely to distinguish the location where the filler member (170) is disposed, and the first filler member (170) and the second filler member (170) may be the same filler member (170).

[0099] A filler member (170) can be placed in the empty space inside the battery assembly (100), more specifically, in the space between the end cover (190) and the battery cell stack (120), and in the space between the battery cell (110) and the busbar frame assembly (130). Accordingly, the filler member (170) fills the empty space inside the battery assembly (100), thereby improving the structural stability of the battery assembly (100).

[0100] Additionally, the filler member (170) including the expandable member can expand in volume when a thermal event or thermal runaway occurs. Accordingly, any empty space that was not filled by the filler member (170) before expansion inside the battery assembly (100) is additionally filled by the expanded filler member (170), thereby preventing venting gas generated from the battery cell (110) from propagating through unintended paths. Meanwhile, detailed information regarding the venting path of the venting gas will be described later.

[0101] FIG. 13 is a cross-sectional view showing the path of refrigerant flow in a battery assembly according to one embodiment of the present invention.

[0102] Referring to FIG. 13, the refrigerant can be introduced into the interior of the battery assembly (100) through the cooling spacer (140) and then flow out of the battery assembly (100) after passing through the battery cell stack (120). As described above, in a single battery cell unit assembly (100UA), the first battery cell unit (100U) and the first busbar frame assembly (130), and the second battery cell unit (100U) and the second busbar frame assembly (130) are arranged symmetrically with respect to each other with the cooling spacer (140) in between. In the case of the present embodiment, due to this arrangement, all battery cells (110) of the battery cell unit assembly (100UA) are in surface contact on the single cooling spacer (140), and all busbars (131) of the busbar frame assembly (130) can be in direct contact with the refrigerant (CL) flowing in the single cooling spacer (140), so efficient cooling can be achieved. Accordingly, the battery assembly (100) according to the present embodiment can achieve improved cooling performance.

[0103] FIG. 14 is a top view showing the arrangement of a busbar sensing unit in a battery assembly according to one embodiment of the present invention.

[0104] Referring to FIG. 14, the battery assembly (100) may include a busbar sensing unit (160) that senses and transmits at least one of the voltage and temperature of a busbar (131). The busbar sensing unit (160) according to the present embodiment may be a component for measuring at least one of the voltage data and temperature data of battery cells (110) and transmitting at least one of the voltage data and temperature data of battery cells (110). The busbar sensing unit (160) may be a component for a so-called LV (Low Voltage) connection. The LV connection refers to an electrical connection that requires a relatively low voltage, such as a battery electrical component. The busbar sensing unit (160) senses the voltage data or temperature data of the battery cells (110) included in the battery assembly (100) and transmits the sensed voltage or temperature data to a Battery Management System (BMS) located inside or outside the battery assembly (100). The above battery management system can control and manage the operation of the battery assembly (100) based on transmitted voltage or temperature data. The busbar sensing unit (160) may be a flexible printed circuit board (FPCB) and / or a flexible flat cable (FFC).

[0105] At this time, each busbar frame assembly (130) disposed in each battery cell unit (100U) of the battery cell stack (120) may be connected in a second direction by a busbar sensing unit (160). Specifically, the busbar sensing unit (160) extending in the second direction may be electrically connected to a busbar (131) of the busbar frame assembly (130) disposed along the second direction. However, the object to which the busbar sensing unit (160) is connected is not limited to the busbar (131). For example, the busbar sensing unit (160) may be connected to the electrode leads (111) of the battery cells (110). Voltage data and / or temperature data of the battery cells (110) measured by the busbar sensing unit (160) may be transmitted to a battery management system located inside or outside the battery assembly (100).

[0106] FIG. 15 is a perspective view of a battery pack according to one embodiment of the present invention. FIG. 16 is an exploded perspective view of the battery pack shown in FIG. 15.

[0107] Referring to FIGS. 15 and 16, a battery pack (1000) according to one embodiment of the present invention may include a battery assembly (100).

[0108] A battery pack (1000) may include a pack frame (1100) in which a battery assembly (100) is housed, and a pack lid (1300) covering an open side of the pack frame (1100). The battery assembly (100) may be housed in the internal space of the pack frame (1100). The pack frame (1100) may include a first pack frame (1110) with an open top surface, front surface, and rear surface, and a second pack frame (1100) covering the front surface and rear surface of the first pack frame (1100). Accordingly, the pack frame (1100) may house the battery assembly (100) with an open top surface.

[0109] The pack lid (1300) can cover the open upper surface of the pack frame (1100). For example, as illustrated in FIG. 16, the pack lid (1300) may be in a shape that covers the upper surface, lower surface, and both sides of the pack frame. The pack frame (1100) containing the battery assembly (100) may be inserted into the pack lid (1300) through the open front and rear surfaces of the pack lid (1300) so that the upper surface of the pack frame (1100) can be covered. Meanwhile, the shape of the pack lid (1300) is not limited by the foregoing. For example, the pack lid (1300) may be in a flat shape that covers only the upper surface of the pack frame (1100). That is, as long as the pack lid (1300) can cover one open surface of the pack frame (1100), it may be modified or changed in various ways depending on the environment in which the present invention is implemented.

[0110] As illustrated in the example in FIG. 16, the battery pack (1000) may include a plurality of battery assemblies (100) and a partition member (1200) disposed between the plurality of battery assemblies. That is, the plurality of battery assemblies (100) may be separated by the partition member (1200).

[0111] A battery pack (1000) according to the present embodiment, which is equipped with a plurality of battery assemblies (100), may be vulnerable to impact in a second direction corresponding to the side of the battery assembly (100). A partition member (1200) according to the present embodiment can support the side of the battery assembly (100) in the second direction. Accordingly, the partition member (1200) for fixing the battery assembly (100) can improve the structural rigidity of the side of the battery assembly (100) in the second direction. Since the partition member (1200) can support the battery assembly (100) even when an impact in the second direction is applied, the overall structure of the battery pack (1000) can be maintained and structural stability can be secured.

[0112] In the battery pack (1000) according to the present embodiment, a plurality of battery assemblies (100) may be provided, and the plurality of battery assemblies (100) may be arranged along the second direction. FIG. 16 illustrates the arrangement of battery assemblies (100) along the second direction. Even if an impact is applied to the battery pack (1000) along the second direction, the battery assemblies (100) can support and complement each other with respect to the second direction, thereby ensuring rigidity in the second direction. Additionally, due to the cooling spacer (140) located between the battery cell stacks (120) arranged along the second direction within the battery assembly (100) and the battery cell units (100U) of the battery cell stacks (120), the structural rigidity of the battery assembly (100) along the second direction can be reinforced, and it can withstand external impacts along the second direction better.

[0113] In this embodiment, by arranging a plurality of battery assemblies (100) within the battery pack (1000) along this second direction, structural rigidity along the second direction can be further supplemented to ensure structural stability against external impact. Additionally, a partition member (1200) may be positioned between the battery assemblies (100) arranged along the second direction. This partition member (1200) can also increase the structural rigidity of the battery assemblies (100).

[0114] FIG. 17 is a top view showing a schematic path of refrigerant flow in a battery pack according to one embodiment of the present invention.

[0115] Referring to FIG. 17, a refrigerant (CL) flowing inside a battery pack (1000) can be introduced into the interior of a battery assembly (100) through the aforementioned cooling spacer (140). After passing through the interior of the battery assembly (100), the refrigerant (CL) can be discharged to the exterior of the battery assembly (100) through the cooling spacer (140). The refrigerant (CL) discharged to the exterior of the battery assembly (100) can pass through a partition member (1200) and flow to an adjacent battery assembly (100). For example, in this embodiment, a plurality of battery assemblies (100) may be arranged along the second direction, and a partition member (1200) may be placed between the battery assemblies (100) arranged along the second direction. Accordingly, the refrigerant (CL) leaked out of the battery assembly (100) can flow to an adjacent battery assembly (100) by passing through the partition member (1200) in the second direction. To this end, the partition member (1200) may be formed with a configuration such as a through hole or a slit through which the refrigerant (CL) can pass, and any structure that allows the refrigerant (CL) to pass through may be modified or changed in various ways depending on the environment in which the present invention is implemented.

[0116] FIG. 18 is a top view showing a battery assembly arranged in a battery pack according to an embodiment of the present invention. FIG. 19 is a top view showing an adhesive arranged in a battery pack according to an embodiment of the present invention. FIG. 20 is a cross-sectional view schematically showing a venting path in a battery pack according to an embodiment of the present invention.

[0117] Referring to FIGS. 18 to 20, a lower adhesive (1400) may be applied to the lower surface of the battery assembly (100). More specifically, the lower adhesive (1400) may be applied to an area corresponding to at least the battery cell stack (120). For example, the lower adhesive (1400) may be applied to an area larger than or equal to the area corresponding to the battery cell stack (120).

[0118] An adhesive may be applied to an adhesive application area (1500) extending in a second direction on the upper surface of the battery cell stack (120). The adhesive application area (1500) on the upper surface of the battery cell stack (120) where the adhesive is applied may be formed in multiple locations spaced apart in a first direction. For example, multiple adhesive application areas (1500) may be formed at both ends of each battery cell (110). More specifically, each battery cell (110) is connected to each other in the first direction to form a battery cell unit (100U), and the battery cell unit (100U) is stacked in the second direction to form a battery cell stack (120). Accordingly, the battery cells (110) of each battery cell unit (100U) may be arranged side by side with the battery cells (110) of the adjacent battery cell unit (100U). The adhesive application area (1500) may be formed adjacent to both ends of the battery cells (110) arranged side by side. That is, the adhesive application area (1500) may be formed by extending in the second direction at a location adjacent to both ends of the battery cells (110).

[0119] Since a plurality of adhesive application areas (1500) are formed extending in the second direction at locations adjacent to both ends of the battery cells (110) and spaced apart in the first direction, an area where no adhesive is applied may be formed between the adhesive application areas (1500) adjacent in the first direction. In the case of the adhesive application areas (1500), the surface of the battery cell stack (120) can be sealed by the adhesive, thereby blocking the movement of venting gas, etc. On the other hand, in the area where no adhesive is applied, the surface of the battery cell stack (120) is not sealed, so the movement of venting gas, etc. is possible. Accordingly, a venting area (1600) in which venting gas (VG), etc. moves between the plurality of adhesive application areas (1500) may be formed on the upper surface of the battery cell stack (120).

[0120] As described above, since the lower adhesive (1400) can be applied to the lower surface of the battery assembly (100), even if venting gas is generated in the battery assembly (100), the movement of venting gas (VG), etc. to the lower surface of the battery assembly (100) can be blocked. Additionally, a filler member (170) can be placed in the empty space inside the battery assembly (100), and the filler member (170) including an expandable member can expand in volume when a thermal event or thermal runaway occurs. Accordingly, the empty space inside the battery assembly (100) is filled by the filler member (170) before expansion and the expanded filler member (170), so even if venting gas (VG) is generated in the battery assembly (100), the movement of venting gas (VG), etc. into the battery assembly (100) can be blocked. Accordingly, the venting gas (VG) generated in the battery assembly (100) can only move through the venting area (1600), and the venting gas (VG) can move toward the upper surface of the battery assembly (100) (i.e., the upper plate (182)) and then be discharged to the outside through the upper surface of the battery pack (1000) (i.e., the pack lid (1300)). Meanwhile, the discharge of the venting gas (VG) can be achieved through a venting device such as a conventional venting valve or a venting part that ruptures at a certain temperature and / or pressure or higher, and as long as the discharge of the venting gas (VG) is possible, it can be modified or changed in various ways depending on the environment in which the present invention is implemented.

[0121] In this embodiment, the cooling of the battery cell (110) is achieved by the flow of refrigerant (CL) through the cooling spacer (140), and since the movement of the venting gas (VG) occurs only through the venting area (1600), the flow of the refrigerant (CL) and the movement of the venting gas (VG) can be separated. Therefore, in this embodiment, since the movement of the venting gas (VG) is separated from and unaffected by the flow of the refrigerant (CL), it can be effective to smoothly discharge the venting gas (VG) to the outside of the battery pack (1000) even if the venting gas (VG) is generated in the battery assembly (100).

[0122] One or more battery assemblies according to the embodiment described above 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.

[0123] The above battery assembly or battery pack can be applied to various devices. Specifically, it can be applied to means of transportation such as electric bicycles, electric vehicles, and hybrids, or to Energy Storage Systems (ESS), but is not limited thereto and can be applied to various devices capable of using secondary batteries.

[0124] Although preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements by those skilled in the art using the basic concept of the present invention as defined in the following claims also fall within the scope of the present invention. Explanation of the symbols

[0125] 100: Battery assembly 110: Battery cell 110U: Battery cell unit 110UA: Battery Cell Unit Assembly 120: Battery cell stack 130: Busbar frame assembly 131: Busbar 132: Busbar Frame 133: Opening 134: Busbar mounting section 135: Spacer insert 136: Step section 140: Cooling Spacer 141: Fluid Channel 142: Open section 150: Pad missing 160: Busbar sensing unit 170: Filler absence 180: Frame 181: Lower frame 182: Upper plate 190: End cover 191: Spacer through hole 192: Injection hole 1000: Battery pack 1100: Pack Frame 1200: Bulkhead member 1300: Pack lid 1400: Bottom adhesive 1500: Adhesive application area 1600: Venting area

Claims

Claim 1 A battery cell unit formed by connecting at least one battery cell to each other in a first direction; a plurality of busbar frame assemblies disposed between the battery cells adjacent in the first direction and at both ends of the battery cell unit; a battery cell stack formed by stacking the battery cell units in a second direction orthogonal to the first direction; and a cooling spacer extending in the first direction and including one or more flow channels through which a refrigerant flows, wherein the cooling spacer is disposed between the battery cell units adjacent in the second direction. Claim 2 A battery assembly according to claim 1, wherein the busbar frame assembly comprises: a busbar electrically connecting the electrode leads of at least one battery cell; and a busbar frame having the busbar disposed on one surface, and the busbar frame includes an opening formed through from the one surface to the other surface opposite to the one surface. Claim 3 A battery assembly, wherein, in paragraph 2, the busbar frame further comprises a busbar mounting portion formed by being recessed from one surface and wherein the busbar is disposed therein. Claim 4 A battery assembly according to paragraph 2, wherein the cooling spacer further comprises an opening formed at a position corresponding to the position where the opening is formed, and the refrigerant flows out from the cooling spacer through the opening and flows into the interior of the busbar frame through the opening, thereby coming into direct contact with the busbar. Claim 5 In paragraph 2, the battery cell unit comprises: a first battery cell unit in which the electrode lead of each of the at least one battery cell is connected to the busbar in the same direction with respect to the second direction; and a second battery cell unit in which the electrode lead of the first battery cell unit is connected to the busbar in a direction opposite to the direction in which the electrode lead is connected to the busbar, and the cooling spacer disposed between the first battery cell unit and the second battery cell unit forms a battery cell unit assembly. Claim 6 A battery assembly according to claim 5, wherein the busbar frame further comprises: a spacer insertion portion formed by being recessed from the other side opposite to the one side; and a step portion formed on the other side as the spacer insertion portion is recessed, and when the cooling spacer is inserted into the spacer insertion portion, a portion of the cooling spacer is caught and fixed in the step portion. Claim 7 In claim 6, the busbar frame assembly comprises: a first busbar frame assembly connected to the first battery cell unit; and a second busbar frame assembly connected to the second battery cell unit, wherein the busbar frame of the first busbar frame assembly and the busbar frame of the second busbar frame assembly are joined such that their respective stepped portions come into contact with each other on the other surface, forming a battery assembly. Claim 8 A battery assembly according to claim 5, further comprising a pad member disposed between the battery cell unit assemblies, wherein the pad member is wrapped with a sheet capable of electrical insulation and moisture prevention. Claim 9 In paragraph 8, the above sheet comprises aluminum, a battery assembly. Claim 10 A battery assembly according to paragraph 2, further comprising a busbar sensing unit that senses and transmits at least one of the voltage and temperature of the busbar, wherein each of the busbar frame assemblies disposed in each battery cell unit of the battery cell stack is connected in the second direction by the busbar sensing unit. Claim 11 A battery assembly according to claim 1, further comprising end covers covering both ends of the battery cell stack with respect to the first direction, wherein the end covers include spacer penetration holes through which the cooling spacer is passed and fixed. Claim 12 A battery assembly according to claim 11, further comprising a filler member disposed in the space between the end cover and the battery cell stack. Claim 13 A battery assembly according to claim 12, wherein the end cover further comprises an injection hole into which the filler member is injected, and the filler member is injected into the space between the end cover and the battery cell stack through the injection hole. Claim 14 In paragraph 13, the battery assembly, wherein the injection hole is formed between the spacer through holes. Claim 15 In claim 12, the battery assembly, wherein the filler member is additionally disposed in the space between the battery cell and the busbar frame assembly. Claim 16 In claim 15, the battery assembly comprises a filler member that expands at a temperature above a predetermined temperature. Claim 17 A battery assembly according to claim 1, wherein an adhesive is applied to an adhesive application area extending in the second direction on the upper surface of the battery cell stack, the adhesive application area is formed in a plurality of spaces spaced apart in the first direction, and a venting area in which a venting gas moves is formed between the plurality of adhesive application areas. Claim 18 In claim 17, the battery assembly wherein the plurality of adhesive application areas are formed at both ends of each of the battery cells. Claim 19 A battery pack comprising a battery assembly according to paragraph 1. Claim 20 A battery pack according to claim 19, wherein the battery assembly is provided in plurality, the plurality of battery assemblies are separated by a partition member, and the refrigerant flows through the partition member to an adjacent battery assembly.

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