Battery packs and cell blocks contained therein, and automobiles containing the same

Abstract

The present invention discloses a battery pack having excellent assembly, processability, safety against thermal runaway, etc. A battery pack according to one aspect of the present invention includes a cell unit stack in which a number of cell units are stacked, a pack case that houses the cell unit stack in its internal space, and side walls that are positioned at ends of the cell unit stack in the internal space of the pack case and configured to support the pack case, and the number of cell units are stacked in at least one direction within the cell unit stack, and the cell unit includes one or more pouch-type battery cells and a cell cover configured to at least partially enclose the pouch-type battery cells.

Description

[Technical Field]

[0001] The present invention relates to a battery pack and a vehicle including the same, and more particularly to a battery pack that includes pouch-type battery cells but can improve assembly, unit components that can constitute such a battery pack, and a vehicle including such a battery pack.

[0002] This application claims priority based on Korean Patent Application No. 10-2022-0089868 filed on July 20, 2022, and Korean Patent Application No. 10-2023-0055757 filed on April 27, 2023, and the contents disclosed in the specifications and drawings of those applications are incorporated herein in their entirety. [Background technology]

[0003] The recent remarkable development of and increasing demand for various mobile devices, electric vehicles, and energy storage systems (ESS) has led to a rapid increase in interest and demand for secondary batteries as an energy source. While nickel-cadmium batteries and nickel-metal hydride batteries were widely used as secondary batteries in the past, lithium secondary batteries have recently come into widespread use due to their flexible charging and discharging capabilities, low self-discharge rate, and high energy density, all of which are less susceptible to memory effects compared to nickel-based batteries.

[0004] This type of lithium secondary battery mainly uses a lithium-based oxide and a carbon material as the positive and negative electrode active materials, respectively, and includes an electrode assembly in which a positive electrode plate and a negative electrode plate, each coated with the positive and negative electrode active materials, are arranged with a separator sandwiched therebetween, and an exterior material, such as a battery case, that encloses the electrode assembly together with an electrolyte.

[0005] Generally, secondary batteries can be classified into can-type secondary batteries, in which an electrode assembly is housed in a metal can, and pouch-type secondary batteries, in which an electrode assembly is housed in a pouch made of an aluminum laminate sheet, depending on the shape of the exterior material.

[0006] Recently, battery packs have been widely used for driving and storing energy in medium- to large-sized devices such as electric vehicles and energy storage systems (ESS). A conventional battery pack includes one or more battery modules and a control unit, such as a battery management system (BMS), that controls the charging and discharging of the battery pack inside a pack case. Here, the battery module is configured to include multiple battery cells inside a module case. That is, in the case of a conventional battery pack, multiple battery cells (secondary batteries) are housed inside a module case to form each battery module, and one or more such battery modules are housed inside a pack case to form a battery pack.

[0007] In particular, pouch-type batteries have various advantages, such as being lightweight and leaving little dead space when stacked, but they have problems such as being vulnerable to external impacts and being somewhat difficult to assemble. Therefore, battery packs are typically manufactured by first modularizing multiple battery cells and then housing them inside a pack case.

[0008] However, conventional battery packs may be disadvantageous in terms of energy density, ease of assembly, cooling performance, etc., due to modularization. Specifically, in the process of modularizing a plurality of battery cells into a module case, various components such as the module case or a stacking frame may increase the volume of the battery pack or reduce the space occupied by the battery cells. First, the process of modularizing a plurality of battery cells to form a battery module and then housing the battery module in a pack case is unavoidable, which complicates the battery pack manufacturing process. Because a module case is housed inside a pack case and battery cells are housed inside the module case, cooling efficiency may decrease when heat from the battery cells housed inside the module case is dissipated to the outside of the pack case through the module case, and the cooling structure may also become complicated.

[0009] Therefore, efforts have been made recently to develop cell-to-pack (CTP) type battery packs. However, the pouch-type battery itself, which is housed in a soft pouch, is not easy to assemble into the battery pack itself, and it is difficult to secure it stably, resulting in problems such as poor processability, ease of assembly, and stability. Summary of the Invention [Problem to be solved by the invention]

[0010] Therefore, the present invention has been devised to solve the above problems, and an object of the present invention is to provide a battery pack that is excellent in processability, assembly efficiency, stability, etc.

[0011] Another problem to be solved by the present invention is to provide unit components that can constitute such a battery pack.

[0012] A further problem that the present invention aims to solve is to provide a vehicle that includes such a battery pack.

[0013] However, the technical problems that the present invention aims to solve are not limited to the above-mentioned problems, and other problems not mentioned will be clearly understood by those skilled in the art from the description of the invention given below. [Means for solving the problem]

[0014] To solve the above problems, one aspect of the present invention provides a battery pack including: a cell unit stack in which a number of cell units are stacked; a pack case that houses the cell unit stack in its internal space; and side walls that are positioned at ends of the cell unit stack in the internal space of the pack case and are configured to support the pack case, wherein the number of cell units are stacked in at least one direction within the cell unit stack; and the cell unit includes one or more pouch-type battery cells and a cell cover that is configured to at least partially enclose the pouch-type battery cells.

[0015] Here, the sidewalls can support the pack case in a horizontal direction perpendicular to the stacking direction of the cell units.

[0016] The pack case may include a lower plate and a plurality of side plates standing upright upward from the lower plate, and the sidewalls may be interposed between the different side plates of the pack case.

[0017] At this time, both ends of the sidewall may be coupled and fixed to different side plates of the pack case.

[0018] The pack case may further include an upper plate coupled to the side plate, and upper and lower ends of the sidewalls may contact the upper and lower plates, respectively.

[0019] Furthermore, the pack case may further include a center beam between the different side plates, and the side walls may be configured to provide support between the side plates and the center beam.

[0020] The sidewall may be configured so that at least one side thereof is larger than the cell unit.

[0021] The sidewalls may be located at both ends of the cell unit in the stacking direction.

[0022] Furthermore, the two sidewalls located at both ends of the cell unit in the stacking direction may have protrusions on their outer surfaces that are located at different positions or symmetrical to each other.

[0023] In one embodiment, multiple cell unit stacks are included along the stacking direction of the cell units, and the sidewall of one cell unit stack is adjacent to the sidewall of another cell unit stack, forming an internal space defined by the two sidewalls.

[0024] The internal space may extend in a horizontal direction perpendicular to the stacking direction of the cell units to form a vent channel.

[0025] The two sidewalls include a first sidewall provided at the right end of the cell unit stack and a second sidewall provided at the left end of the cell unit stack in the left-right direction along the stacking direction of the cell units, and the first sidewall has a protrusion formed at the top or bottom so as to protrude toward the right, and the second sidewall has a protrusion formed at the bottom or top so as to protrude toward the left, wherein the first sidewall of one cell unit stack and the second sidewall of the other cell unit stack are adjacent to each other to form the internal space.

[0026] The protruding portion of the first sidewall and the protruding portion of the second sidewall may be positioned at different positions in the horizontal or vertical direction so as not to interfere with each other.

[0027] The protrusion of the first sidewall may be an extension of the main body of the first sidewall that is bent so as to be perpendicular to the surface direction of the main body of the first sidewall, and the protrusion of the second sidewall may be an extension of the main body of the second sidewall that is bent so as to be perpendicular to the surface direction of the main body of the second sidewall.

[0028] The protrusion of the first sidewall may contact or be bonded to the second sidewall, or the protrusion of the second sidewall may contact or be bonded to the first sidewall, or the protrusion of the first sidewall may contact or be bonded to the protrusion of the second sidewall.

[0029] Either the first sidewall or the second sidewall may further be provided with a protrusion formed to protrude outward in the front or rear direction.

[0030] The sidewalls may also protrude above the cell unit stack, and inlet holes may be formed in the protruding portions of the sidewalls.

[0031] The pouch-type battery cell may include a receiving portion in which an electrode assembly is received and an edge portion around the receiving portion, and the cell cover may be configured to enclose both sides of the receiving portion of the pouch-type battery cell and a portion of the edge portion.

[0032] According to another aspect of the present invention to solve the above problem, there is provided a cell block as a unit component that can constitute such a battery pack. The cell block according to the present invention includes a cell unit stack in which a number of cell units are stacked, and sidewalls located at ends of the cell unit stack, where the number of cell units are stacked in at least one direction within the cell unit stack, the cell unit including one or more pouch-type battery cells and a cell cover configured to at least partially enclose the pouch-type battery cells, and the sidewalls are located at both ends of the cell units in the stacking direction.

[0033] Here, the two sidewalls located at both ends of the cell unit in the stacking direction may have protrusions on their outer surfaces that are provided at different positions or symmetrical to each other.

[0034] In addition, a vehicle according to yet another aspect of the present invention for solving the still other object includes the battery pack according to the present invention. [Effects of the Invention]

[0035] According to one aspect of the present invention, a plurality of pouch-type battery cells can be stably accommodated inside a pack case without components such as a frame for stacking, such as a plastic cartridge, or a separate module case.

[0036] Furthermore, according to one aspect of the present invention, a configuration in which pouch-type battery cells housed in soft pouches can be easily made into a rigid form and directly stacked inside a pack case can be more easily realized, thereby improving the ease of assembly and mechanical stability of the battery pack.

[0037] In particular, according to one embodiment of the present invention, it is possible to more easily realize a configuration in which a plurality of pouch-type battery cells are stacked in a state in which they are vertically upright and aligned horizontally.

[0038] In particular, according to another aspect of the present invention, a cell block is provided in which cell units including pouch-type battery cells are blocked, and a battery pack can be easily constructed using such a cell block, and a large number of cell units can be efficiently fixed within the cell block.

[0039] According to another embodiment of the present invention, cross beams can be formed automatically when cell blocks including a plurality of cell units are placed adjacent to each other inside a pack case. Therefore, a separate cross beam need not be included inside the pack case, or the number of separate cross beams can be significantly reduced. Furthermore, in this case, a process for inserting cell units into spaces defined by separate cross beams pre-installed inside the pack case is not required. Furthermore, according to the above embodiment, a process for pre-installing cross beams inside the pack case is not required. Therefore, these various aspects contribute to improved processability in manufacturing battery packs.

[0040] According to another embodiment of the present invention, a vent channel can be formed simply by placing multiple cell blocks inside the pack case. Therefore, in the present invention, the accumulation and discharge of heat, which corresponds to the ignition source among the three elements that cause a flame (fuel, oxygen, and ignition source), can be blocked or appropriately controlled. Furthermore, in the present invention, the rapid and smooth discharge of vent gas can block heat accumulation and prevent explosions due to increased internal pressure. Furthermore, in the present invention, a directional vent configuration can be easily realized.

[0041] Furthermore, according to one aspect of the present invention, a CTP concept battery pack is provided, in which a module case, etc. is omitted, thereby improving cooling performance and energy density, etc.

[0042] The following drawings attached to this specification illustrate preferred embodiments of the present invention and serve to further understand the technical concepts of the present invention as well as the content of the invention, and therefore the present invention should not be interpreted as being limited to only the matters described in the drawings. [Brief explanation of the drawings]

[0043] [Figure 1] 1 is a schematic diagram of a battery pack according to one embodiment of the present invention. [Figure 2] FIG. 2 is a perspective view schematically illustrating the configuration of a cell block included in the battery pack of FIG. [Figure 3] FIG. 3 is an exploded perspective view of a part of the configuration of FIG. 2. [Figure 4] FIG. 3 is a perspective view showing one cell unit included in the cell block of FIG. 2. [Figure 5] FIG. 5 is an exploded perspective view showing the cell unit shown in FIG. [Figure 6] FIG. 5 is a diagram schematically showing a cross-sectional configuration of the cell unit of FIG. [Figure 7] FIG. 10 is a diagram illustrating a schematic configuration of a portion of a battery pack according to another embodiment of the present invention. [Figure 8] 10 is a perspective view schematically illustrating a configuration of a right end portion of a cell block according to another embodiment of the present invention. FIG. [Figure 9] 10 is a perspective view schematically illustrating a configuration of a left end portion of a cell block according to another embodiment of the present invention; FIG. [Figure 10] FIG. 10 is a front view schematically illustrating the coupling configuration of the sidewalls when two cell blocks are placed next to each other. [Figure 11] FIG. 10 is a front view schematically illustrating the coupling configuration of the sidewalls when two cell blocks are placed next to each other. [Figure 12] FIG. 10 is a perspective view schematically showing a configuration in which a vent channel is formed by joining sidewalls between two adjacent cell blocks. [Figure 13]10 is a perspective view showing a sidewall coupled to a right end of a cell block according to still another embodiment of the present invention; FIG. [Figure 14] 10 is a perspective view showing a sidewall coupled to a left end of a cell block according to still another embodiment of the present invention; FIG. [Figure 15] FIG. 15 is a front view schematically illustrating the coupling configuration of the sidewalls shown in FIGS. 13 and 14 when two cell blocks are placed adjacent to each other according to yet another embodiment of the present invention. [Figure 16] 1 is a diagram illustrating a schematic configuration of a vehicle according to an embodiment of the present invention; DETAILED DESCRIPTION OF THE INVENTION

[0044] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Terms and words used in this specification and claims should not be construed as being limited to their ordinary or dictionary meanings, but should be construed as meanings and concepts corresponding to the technical ideas of the present invention, based on the principle that the inventor himself can appropriately define the concepts of terms in order to best explain the invention. Therefore, it should be understood that the embodiment described in this specification and the configuration shown in the drawings are merely the most preferred embodiment of the present invention and do not represent the entire technical ideas of the present invention, and therefore various equivalents and modifications that can be substituted therefor may exist at the time of filing this application.

[0045] In the drawings, the size of each component or specific parts of the component may be slightly exaggerated, omitted, or illustrated schematically for ease of explanation and clarity. Therefore, the size of each component does not fully reflect the actual size. If a detailed description of related known functions or configurations is deemed to be likely to unnecessarily obscure the gist of the present invention, such detailed description will be omitted. For reference, terms and phrases indicating directions in this specification are based on the components shown in the accompanying drawings and have relative meanings that may change depending on the actual posture and position of the components.

[0046] Fig. 1 is a schematic diagram of a battery pack according to one embodiment of the present invention, Fig. 2 is a perspective view schematically showing the configuration of a cell block included in the battery pack of Fig. 1, and Fig. 3 is an exploded perspective view of part of the configuration of Fig. 2.

[0047] First, referring to FIG. 1, a battery pack 10 according to one embodiment of the present invention may include a number of cell units 100, a pack case 400, and a sidewall 500.

[0048] A large number of cell units 100 may be included in the battery pack 10. The large number of cell units 100 may be stacked in at least one direction inside the pack case 400. For example, as shown in FIGS. 1 to 3, the large number of cell units 100 may be arranged facing each other in the left-right direction, for example, in the horizontal direction (Y-axis direction).

[0049] 2 and 3, a number of cell units 100 are stacked to form a cell unit stack 300. The cell units 100 are stacked in at least one direction in the cell unit stack 300. In FIG. 1, a pack case 400 accommodates the cell unit stack 300 in its internal space. The pack case 400 may be made of plastic or metal. Alternatively, the pack case 400 may be made of various battery pack exterior materials known at the time of filing of the present invention.

[0050] The cell unit stack 300 and the sidewalls 500 form a cell block 600. That is, the cell block 600 according to the present invention may include a number of cell units 100 and sidewalls 500, as shown in Figures 2 and 3. Figure 1 schematically shows a configuration in which two cell blocks 600 according to an embodiment of the present invention are placed in a pack case 400.

[0051] First, a large number of cell units 100 are mounted in a pack case 400 to form a cell unit stack 300, and then sidewalls 500 are attached to the stack to form a cell block 600. As another example, it is also possible to form the cell unit stack 300 by stacking a large number of cell units 100 together by a method such as bonding outside the pack case 400, and then attach this to the pack case 400 and attach the sidewalls 500. As yet another example, it is also possible to form the cell unit stack 300 outside the pack case 400, and then attach the sidewalls 500 to the stack to form a cell block 600, and then attach this to the pack case 400. In particular, by stacking a large number of cell units 100 and positioning two sidewalls 500 at both ends of the cell units 100 in the stacking direction, the cell units 100 are blocked and fixed by the pair of sidewalls 500, which makes it easy to handle and install the pouch-type battery cells to be installed in the battery pack 10, while also simplifying and reducing the weight of the structure required to install the pouch-type battery cells, thereby reducing manufacturing costs.

[0052] Heat insulating pads, flame suppression pads, etc. may be interposed at least partially between the multiple cell units 100 in the cell unit stack 300. Such heat insulating pads and flame suppression pads can prevent heat or flames that may occur in one cell unit 100 from propagating to and affecting the other cell units 100. The flame suppression pads may be formed from a heat-resistant resin such as polyvinyl chloride resin, a material such as silicon or ceramic, a complex of a heat-resistant resin with a ceramic or glass filler, or a metal plate with an insulating coating, but these are merely exemplary and any flame-retardant material may be used. It is preferable that the flame suppression pads be made of a material that does not decompose, dissolve, or complex at least up to a temperature (e.g., 150°C to 200°C) at which the pouch-type battery cell experiences thermal runaway.

[0053] Furthermore, when the battery pack 10 includes a number of stacked cell units 100, an adhesive member may be interposed between the cell units 100. For example, an adhesive member may be interposed between two cell units 100 that face each other to bond and fix them. This adhesive structure can further strengthen the connection structure between the number of cell units 100.

[0054] Fig. 4 is a perspective view showing one cell unit included in the cell block of Fig. 2, Fig. 5 is an exploded perspective view showing the cell unit shown in Fig. 4, and Fig. 6 is a diagram schematically showing the cross-sectional configuration of the cell unit of Fig. 4.

[0055] 4 to 6, the cell unit 100 may include a pouch-type battery cell 110 and a cell cover 200. According to this aspect of the present invention, the cell cover 200 is coupled to the pouch-type battery cell 110, thereby effectively protecting the pouch-type battery cell 110 without a module case.

[0056] The pouch-type battery cell 110 may include an electrode assembly, an electrolyte, and a pouch exterior material. A plurality of such pouch-type battery cells 110 may be included in the battery pack 10. As shown in FIG. 5 , each pouch-type battery cell 110 may have a receiving portion indicated by "R" and edge portions indicated by "E1" to "E4." Here, the receiving portion R may be a portion that receives an electrode assembly formed by stacking a positive electrode plate and a negative electrode plate with a separator interposed therebetween. The receiving portion R may also receive an electrolyte. The edge portions E1 to E4 may be arranged in a shape that surrounds the receiving portion R.

[0057] In particular, the edge portions E1 to E4 may be seal portions where the pouch exterior material, which is the case of the pouch-type battery cell 110, is sealed. For example, in the embodiment of FIG. 5, four edge portions E1 to E4 are provided, and they can be said to be located at the upper edge, the lower edge, the front edge, and the rear edge, respectively, based on the storage portion R. In this case, all four edge portions E1 to E4 may be seal portions. Alternatively, some of the four edge portions E1 to E4 may be formed in a folded shape rather than being sealed. For example, in the embodiment of FIG. 5, the upper edge portion E1, the front edge portion E3, and the rear edge portion E4 are all seal portions, but the lower edge portion E2 may be a portion where the pouch exterior material is folded. For example, the upper edge portion E1 may be a portion that is folded twice at the sealed portion of the pouch-type battery cell 110, a so-called double-side folded (DSF) portion, and the lower edge portion E2 may be an unsealed portion of the pouch-type battery cell 110.

[0058] One cell unit 100 may include one or more such pouch-type battery cells 110. For example, each cell unit 100 may be provided with three pouch-type battery cells 110. When each cell unit 100 includes multiple pouch-type battery cells 110, the multiple pouch-type battery cells 110 may be stacked in at least one direction, for example, the left-right direction, with the housing portions R facing each other. For example, when the direction along the major axis of the pouch-type battery cell 110 is defined as the longitudinal direction (X-axis direction), the pouch-type battery cells 110 may be stacked in the width direction perpendicular to this longitudinal direction.

[0059] The cell cover 200 may be provided to at least partially encase the pouch-type battery cell 110. For example, the cell cover 200 may be configured to at least partially encase three pouch-type battery cells 110, as shown in Figures 5 and 6.

[0060] The cell unit 100 may further include a bus bar frame 130 and an insulating cover 140 .

[0061] The bus bar frame 130 may be configured to support the electrode lead 120 of at least one pouch-type battery cell 110 covered by the cell cover 200, and to electrically connect such electrode lead 120 to the electrode leads 120 of other pouch-type battery cells 110. In this case, the bus bar frame 130 may include terminals to be electrically connected to the electrode leads 120.

[0062] The insulating cover 140 may be configured to prevent short-circuiting of the electrode leads 120 or the bus bars, and for this purpose, the insulating cover 140 may be made of a polymeric synthetic resin having insulating properties.

[0063] Furthermore, when the electrode leads 120 are provided on both sides of the pouch-type battery cell 110, the bus bar frame 130 and the insulating cover 140 may also be included on both sides where the electrode leads 120 are provided. For example, as shown in Fig. 5, when the electrode leads 120 protrude from both the front side (X-axis direction in the figure) and the rear side (-X-axis direction in the figure), the bus bar frame 130 and the insulating cover 140 may also be located on both the front side and the rear side.

[0064] Within the cell cover 200, one or more pouch-type battery cells 110 may be formed in a shape that stands upright in the vertical direction (Z-axis direction). As shown in FIG. 5 , each pouch-type battery cell 110 has two wide surfaces where the housing portion R is located, and edge portions E1 to E4, which are the peripheral portions of the wide surfaces, may have narrow surfaces due to the presence of sealed or folded portions of the pouch exterior material. Therefore, it is generally difficult to stack pouch-type battery cells 110 in a shape that stands upright in the vertical direction with the narrow surfaces facing downwards. However, in the battery pack 10 according to the present invention, the cell cover 200 may be configured to encase one or more pouch-type battery cells 110 and support the enclosed pouch-type battery cells 110 in an upright, i.e., standing, state.

[0065] In addition, in the pouch-type battery cell 110, the upper edge E1, which is a sealed portion, may be more vulnerable to the discharge of high-temperature gas or flame than the lower edge E2, which is an unsealed portion. However, according to the above embodiment, the upper edge E1, which is a sealed portion, is disposed to face the cell cover 200, which may be more advantageous for directional venting.

[0066] The cell cover 200 may be made of a metal material. In particular, the cell cover 200 may be made of a steel material. Furthermore, the cell cover 200 may be made of a stainless steel material. When the cell cover 200 is made of a stainless steel material, it has excellent mechanical strength and rigidity, and can more stably support the stacked state of the pouch-type battery cells 110. In this case, damage or breakage of the pouch-type battery cells 110 due to external impact, for example, a needle-shaped object, can be more effectively prevented. Furthermore, in this case, the pouch-type battery cells 110 can be more easily handled.

[0067] Furthermore, even if a fire occurs in a specific battery cell, the cell cover 200 can be more effectively prevented from melting due to the flame. If the cell cover 200 is made of SUS material, its high melting point allows the overall structure to be stably maintained when a flame occurs in the pouch-type battery cell 110. In particular, since SUS material has a higher melting point than aluminum material, it is not melted by the flame emitted from the pouch-type battery cell 110 and its shape can be stably maintained. Therefore, it is possible to effectively prevent or delay the spread of flame between the pouch-type battery cells 110 and to effectively control venting, and even when a thermal event occurs, it is possible to prevent internal short circuits and structural collapse, thereby increasing structural safety.

[0068] For example, the cell cover 200 may be directly placed on the bottom surface of the pack case 400. In this case, a part of the cell cover 200, for example, the lower end of the cell cover 200, may be placed in direct contact with the bottom surface of the pack case 400. The cell cover 200 may be configured to stably maintain its placed state when its lower end is placed in this manner. In this case, if the cell cover 200 is made of a stainless steel material, the self-standing state can be maintained more stably. Therefore, in this case, the upright state of the pouch-type battery cell 110 can be more firmly supported.

[0069] The cell cover 200 may be formed to a thickness of approximately 2 mm. However, the cell cover 200 may be formed to have different thicknesses in parts. Also, the cell cover 200 may have polyimide (PI) films of approximately 0.5 mm thickness attached to both sides for insulation.

[0070] The cell cover 200 may also include an insulating coating layer (not shown) on its inner surface. The insulating coating layer may be formed by coating, applying, or attaching an insulating material such as silicone resin, polyamide, or rubber. The insulating coating layer configuration of the cell cover 200 according to this embodiment maximizes the insulating coating effect with a minimal amount of coating. In addition, since the insulating coating layer (not shown) is applied to the inner surface of the cell cover 200, the insulation between the pouch-type battery cell 110 and the cell cover 200 can be strengthened.

[0071] The cell cover 200 may be formed in a shape that partially encloses the pouch-type battery cell 110 so that at least one side of the enclosed pouch-type battery cell 110 is exposed to the outside. That is, the cell cover 200 may be formed in a shape that encloses only a portion of the pouch-type battery cell 110 rather than completely enclosing the entire pouch-type battery cell 110. In particular, the cell cover 200 may be configured so that at least one side of the pouch-type battery cell 110 is exposed toward the pack case 400. In this regard, the cell cover 200 may be referred to as a cell sleeve or the like.

[0072] In particular, the cell cover 200 may be formed in a shape that encloses edge portions of the pouch-type battery cell 110 housed therein that are not provided with electrode leads. For example, referring to the embodiment shown in FIG. 5, the pouch-type battery cell 110 may have two electrode leads 120, i.e., a positive electrode lead and a negative electrode lead. In this case, the two electrode leads may be located at the front edge portion E3 and the rear edge portion E4, respectively. In this case, the cell cover 200 may be formed in a shape that encloses either one of the remaining two edge portions E1 and E2, excluding the front edge portion E3 and the rear edge portion E4. The cell cover 200 may enclose the upper edge portion E1 of the pouch-type battery cell 110 and leave the lower edge portion E2 exposed.

[0073] The pouch-type battery cell 110 can be said to be formed in a roughly hexahedral shape. Electrode leads 120, i.e., a negative electrode lead and a positive electrode lead, may be formed on two of the six sides. The cell cover 200 may be provided to enclose at least a portion of three of the remaining four sides of the six-sided pouch-type battery cell 110, excluding the two sides on which the electrode leads 120 are formed. In this manner, the cell cover 200 may be configured to have openings formed on both sides corresponding to the electrode leads 120.

[0074] According to this embodiment of the present invention, the direction of the discharge of a flame or the like can be guided toward the opening of the cell cover 200. For example, according to the above embodiment, the front and rear sides of the cell cover 200 where the electrode lead 120 is located are open, so that the discharge of a flame or the like can be directed in the direction of the opening. In particular, when the cell cover 200 is formed with the front and rear open as described above, side directional venting can be easily achieved. Alternatively, when the bottom or top end of the cell cover 200 is formed with an open shape, directional venting can be performed toward the open side (open end) of the bottom or top end of the cell cover 200.

[0075] Furthermore, the cell cover 200 may be provided in a shape that covers both side surfaces and an upper edge portion E1 of the accommodation portion R of one or more pouch-type battery cells 110 accommodated and enclosed therein. For example, when the cell cover 200 is formed in a shape that encloses three pouch-type battery cells 110 stacked in the left-right direction, the cell cover 200 may be formed in a shape that encloses the left surface of the accommodation portion R of the left pouch-type battery cell 110, the upper edge portion E1 of the pouch-type battery cell 110, and the right surface of the accommodation portion R of the right pouch-type battery cell 110. In this case, the cross-sectional shape of the cell cover 200 viewed from the front side can be said to be roughly similar to the letter "n." Therefore, in this case, the cell cover 200 may be referred to as an "n-fin."

[0076] More specifically, the cell cover 200 may include an upper cover portion 220, a first side cover portion 230, and a second side cover portion 240. Here, the upper cover portion 220 may be configured to enclose an upper portion of the upper edge portion E1 of the pouch-type battery cell 110 housed therein. The upper cover portion 220 may be formed in a flat shape. In this case, the cross section of the upper cover portion 220 may be formed in a horizontally linear shape, and may enclose the upper edge portion E1 of the pouch-type battery cell 110 from the outside in a linear shape.

[0077] The first side cover part 230 may be formed in a shape extending downward from one end of the upper cover part 220. For example, the first side cover part 230 may be formed in an elongated shape extending downward from the left end part of the upper cover part 220 (in the -Z-axis direction in the figure). Furthermore, the first side cover part 230 may be formed in a flat shape. In this case, the first side cover part 230 may be formed in a curved shape at the upper cover part 220. The first side cover part 230 may be configured to enclose the outside of the accommodation part R on one side of the pouch-type battery cell 110 accommodated therein.

[0078] The second side cover part 240 may be positioned so as to be horizontally spaced apart from the first side cover part 230. The second side cover part 240 may be formed in a shape extending downward from the other end of the upper cover part 220. For example, the second side cover part 240 may be formed in a shape extending downward from the right end part of the upper cover part 220 in an elongated shape. The second side cover part 240 may also be formed in a planar shape like the first side cover part 230. In this case, the second side cover part 240 and the first side cover part 230 can be said to be arranged parallel to each other while being horizontally spaced apart from each other. The second side cover part 240 may be configured to enclose the outside of the other side housing part R of the pouch-type battery cell 110 housed therein.

[0079] According to this embodiment of the present invention, it is possible to easily realize a configuration in which one or more battery cells are supported and protected by one cell cover 200. In particular, according to the above embodiment, the lower edge portion E2 is positioned adjacent to the open end of the cell cover 200, and faces the pack case 400 without being enclosed by the cell cover 200, so that it can be in direct face-to-face contact with the pack case 400. Therefore, heat from the pouch-type battery cells 110 enclosed by the cell cover 200 can be quickly and smoothly dissipated to the lower pack case 400 side. Therefore, the cooling performance of the battery pack 10 can be more effectively ensured.

[0080] In particular, this configuration can be implemented more effectively when cooling is mainly performed in the lower part of the pack case 400. For example, in the case of a battery pack mounted on an electric vehicle, since it is mounted on the lower part of the vehicle body, cooling can mainly be performed in the lower part of the pack case 400. In this case, when the lower edge portion E2 of each pouch-type battery cell 110 faces and contacts the pack case 400 as in the above embodiment, heat is quickly transferred from each pouch-type battery cell 110 to the pack case 400, and cooling performance can be further improved.

[0081] Furthermore, according to the above embodiment, when high-temperature gas or flame is emitted from the pouch-type battery cell 110 in a situation such as thermal runaway, the emitted gas or flame can be effectively prevented from heading upward. In particular, when a passenger is positioned on the upper side of the battery pack 10, such as in an electric vehicle, according to the above embodiment, it is possible to prevent or delay the gas or flame from heading toward the passenger.

[0082] As described above, according to the present invention, even if a flame or gas is emitted from a pouch-type battery cell 110, it can be guided and discharged in a predetermined direction. In this case, even if thermal runaway occurs in one of the pouch-type battery cells 110, the flame or gas generated in that pouch-type battery cell 110 is discharged only in the predetermined direction through the cell cover 200. If the predetermined direction is a direction that does not direct the flame or gas toward other cell covers 200, it is possible for the flame or gas to not spread to other pouch-type battery cells 110 arranged adjacent to the pouch-type battery cell 110 in which thermal runaway has occurred. In other words, even if thermal runaway occurs in one of the pouch-type battery cells 110, the impact of the thermal runaway on the other pouch-type battery cells 110 is minimized.

[0083] The cell cover 200 may be formed as a single unit. In this case, the cell cover 200 may be formed by bending a metal plate having a plate-like structure. That is, the cell cover 200 may be formed in a shape in which a single plate is bent.

[0084] The cell cover 200 may be formed into a shape that encloses one or more pouch-type battery cells 110 by bending both ends of a single plate material in the same direction. In particular, when one cell cover 200 is provided with an upper cover portion 220, a first side cover portion 230, and a second side cover portion 240, the upper cover portion 220, the first side cover portion 230, and the second side cover portion 240 may be made of a single plate. In this case, the cell cover 200 can be said to be made of multiple components that are integrally formed.

[0085] Here, each component may be separated via a folding portion. In particular, two folding portions may be formed in one plate. The upper cover portion 220, the first side cover portion 230, and the second side cover portion 240 may be separated based on these two folding portions. In particular, the central portion of one plate may form the upper cover portion 220, and both sides of the upper cover portion 220 may be bent or folded downwardly around the upper cover portion 220 to form the first side cover portion 230 and the second side cover portion 240. Forming folding portions in one plate to form the cell cover 200 in this manner may be achieved by various methods, such as pressing or roll forming.

[0086] According to this embodiment of the present invention, it is possible to further simplify the manufacture of the cell cover 200. In addition, the cell cover 200 having a simplified structure is made of a metal material having higher rigidity than the case of the pouch-type battery cell 110, such as a pouch exterior material, and can protect at least one pouch-type battery cell 110 covered by the cell cover 200 from external impact and vibration. In addition, in this case, the heat conduction performance via the cell cover 200 is further improved, thereby further improving the cooling performance.

[0087] The first side cover part 230 and the pouch-type battery cell 110, and the second side cover part 240 and the pouch-type battery cell 110 may be bonded together. The first side cover part 230 and the pouch-type battery cell 110, and the second side cover part 240 and the pouch-type battery cell 110 may be bonded together directly, or may be bonded together indirectly by further including an insulating member.

[0088] The cell cover 200 may be provided with venting holes at various positions along the intended venting direction. Such venting holes may be provided by forming notches in predetermined portions of the cell cover 200. As shown in FIGS. 4 and 5, the cell cover 200 may have a vent hole 210 formed in the upper cover part 220. Such vent hole 210 may be formed in a shape that penetrates between the inner and outer spaces of the cell cover 200 so that gas can be discharged from the inner space to the outside.

[0089] In this manner, one or more pouch-type battery cells 110 and the cell cover 200 configured to at least partially enclose the pouch-type battery cells 110 may constitute one cell unit 100. In particular, such a cell unit 100 may be referred to as a scalable pouch unit (SPU) because the number of pouch-type battery cells 110 housed inside the cell cover 200 can be adjusted by, for example, adjusting the width of the cell cover 200. Therefore, in this case, it is possible to easily change the capacity or output of one cell cover 200. A battery pack 10 may include a large number of cell units 100, and the scale can be easily expanded by increasing the number of cell units 100.

[0090] Such a cell unit 100 makes it easier to handle and install the pouch-type battery cells 110 during the manufacturing process of the battery pack 10 including the pouch-type battery cells 110, and has the effect of simplifying and reducing the weight of the structure required to install the pouch-type battery cells 110 while preventing damage to the pouch-type battery cells 110, as well as making it possible to flexibly accommodate changes in capacity and output.

[0091] The cell cover 200 can be configured to support the stacked state of the plurality of pouch-type battery cells 110 inside the pack case 400 by using a structure that encases the battery cells in this way. For example, the plurality of pouch-type battery cells 110 can be stacked in a horizontal direction. In this case, the cell cover 200 can be configured to stably maintain the stacked state of the plurality of pouch-type battery cells 110 stacked in this horizontal direction.

[0092] According to this aspect of the present invention, a plurality of pouch-type battery cells 110 can be directly placed and housed inside the pack case 400 without a module case. In particular, the exterior material of the pouch-type battery cells 110 is made of a soft material, such as an aluminum laminate sheet pouch, making them vulnerable to external impacts and also low in hardness. Therefore, it is not easy to house the pouch-type battery cells 110 themselves inside the pack case 400 without housing them in a module case. However, in the present invention, the plurality of pouch-type battery cells 110 are directly housed inside the pack case 400 while being at least partially enclosed by the cell cover 200 and coupled to the cell cover 200, allowing the stacked state to be stably maintained.

[0093] Furthermore, the present invention can more efficiently realize a CTP-type battery pack using the pouch-type battery cells 110. That is, the present invention does not require that the pouch-type battery cells 110 be accommodated inside a separate module case and then that module case be accommodated inside the pack case 400, but rather that the battery pack 10 be provided in a form in which the pouch-type battery cells 110 are directly accommodated inside the pack case 400. In this case, at least one side of the pouch-type battery cells 110 may be exposed to the outside of the cell cover 200 and disposed so as to directly face the pack case 400.

[0094] Therefore, according to this aspect of the present invention, the battery pack 10 does not need to be provided with additional fastening members such as a module case, a stacking frame, or bolts for maintaining the stacked state of the cells. Therefore, it is possible to eliminate the space occupied by other components such as the module case and the stacking frame, and the space required to ensure tolerances. Therefore, the battery cells can occupy the additional space corresponding to the eliminated space, thereby further improving the energy density of the battery pack. In particular, by directly assembling the pouch-type battery cells 110 having a soft case into the pack case 400 of the battery pack 10, the space utilization rate of the battery pack 10 can be maximized, and the energy capacity can be significantly improved.

[0095] Furthermore, according to this aspect of the present invention, since a module case, stacking frame, bolts, etc. are not required, the volume and weight of the battery pack can be reduced and the manufacturing process can be simplified.

[0096] The present invention can improve the assembly efficiency of the battery pack 10. In particular, according to one embodiment of the present invention, it is not necessary to perform a process of accommodating pouch-type battery cells 110 in a module case to provide a battery module, and a process of accommodating one or more battery modules thus provided in the pack case 400. This simplifies the manufacturing process and shortens the manufacturing time.

[0097] Furthermore, according to this aspect of the present invention, handling of the pouch-type battery cells 110 becomes even easier. For example, when a plurality of pouch-type battery cells 110 are housed inside the pack case 400, the pouch-type battery cells 110 may be gripped by a jig or the like. In this case, the jig does not directly grip the pouch-type battery cells 110, but may grip the cell covers 200 that encase the pouch-type battery cells 110 or the sidewalls 500. This makes it possible to prevent the pouch-type battery cells 110 from being damaged or broken by the jig.

[0098] Returning to FIG. 1 , as shown in FIG. 1 , the pack case 400 has an empty space formed therein, and can accommodate a plurality of cell unit stacks 300 in this internal space. In particular, the pack case 400 includes a bottom plate 410 and a plurality of side plates 420 standing upright upward from the bottom plate 410. A plurality of cell units 100 or a plurality of cell unit stacks 300 can be directly placed on the upper surface of the bottom plate 410 of the pack case 400. Furthermore, the lower ends of the cell covers 200 can be placed in direct contact with the bottom plate 410 of the pack case 400. In addition, the lower ends of the pouch-type battery cells 110 housed inside the cell covers 200 can also be placed directly on the bottom plate 410 of the pack case 400. In this way, the bottom plate 410 and the side plates 420 of the pack case 400 form a box-shaped lower case with an open top, and a plurality of cell unit stacks 300 can be accommodated in its internal space.

[0099] In particular, the pack case 400 accommodates the pouch-type battery cells 110 in an upright state with the edge portions E1 to E4 of the pouch-type battery cells 110 facing downward in the internal space. In the embodiment of Figures 1 to 6, an example is given in which the lower edge portion E2 of the pouch-type battery cell 110 is facing downward.

[0100] The sidewalls 500 may be located at the ends of the cell unit stacks 300 in the internal space of the pack case 400. The sidewalls 500 may be located at the ends of the cell units 100 in the stacking direction. In particular, the sidewalls 500 may be coupled to the outer periphery of the cell unit stacks 300 in the stacking direction. Here, the sidewalls 500 may be coupled to the cell unit stacks 300 by various fastening methods such as bolting, welding, hooks, etc. Furthermore, the sidewalls 500 may fix the stacked state of the cell unit stacks 300.

[0101] The sidewalls 500 may also be configured to support the pack case 400. For example, when the cell block 600 is placed in the interior space of the pack case 400, the sidewalls 500 may be interposed between different side plates 420 of the pack case 400. For example, as shown in the embodiment in FIG. 1 , the sidewalls 500 may be interposed between a front plate 420a and a rear plate 420b, which are internal components of the pack case 400 and stand facing each other in opposite directions. In particular, both ends of the sidewalls 500 may be coupled and fixed to the front plate 420a and the rear plate 420b, respectively.

[0102] According to this embodiment of the present invention, the sidewalls 500 of the cell block 600 can not only maintain the stacked state inside the cell block 600 but also serve to mechanically support the pack case 400 on which the cell block 600 is placed. In particular, the sidewalls 500 can also function as pack beams or cross beams by supporting the different side plates 400 (front plate 420a, rear plate 420b) of the pack case 400. Therefore, the overall shape of the pack case 400 can be maintained while protecting the components housed therein despite external impact. In this case, cross beams and other components included in conventional battery packs can be eliminated or reduced. As a result, assembly convenience and processability can be improved during the manufacture of the battery pack 10, while manufacturing costs and time can be reduced.

[0103] When the pack case 400 is made of a lightweight material such as aluminum to reduce weight, the sidewalls 500 can further supplement the rigidity of such a pack case 400. Furthermore, the sidewalls 500 of the cell block 600 have the effect of blocking or grouping a large number of cell units 100 and distributing the pressure applied to the large number of cell units 100 evenly across the entire cell unit 100.

[0104] Furthermore, the sidewalls 500 may support the pack case 400 in a horizontal direction perpendicular to the stacking direction of the cell units 100, for example, in the front-to-rear direction (X-axis direction). Alternatively, the sidewalls 500 may support the pack case 400 in the up-down direction. For example, the pack case 400 may further include an upper plate 430 coupled onto the side plate 420, and the upper and lower ends of the sidewalls 500 may be configured to contact the upper plate 430 and the lower plate 410, respectively, to provide support between the lower plate 410 and the upper plate 430, which are the bottom and top surfaces of the pack case 400.

[0105] 7 is a diagram schematically illustrating a configuration of a portion of a battery pack according to another embodiment of the present invention, in which two cell blocks 600 are mounted in a pack case 400.

[0106] As shown in FIG. 7 , a center beam 440 may be formed in the center of the pack case 400. For example, the pack case 400 may further include the center beam 440 between the different side plates 420a, 420b. In this case, the sidewalls 500 of the cell block 600 may be interposed between the center beam 440 and the side plates 420. The sidewalls 500 may be configured to provide support between the center beam 440 and the side plates 420. The cell blocks 600 may be aligned along the Y-axis direction as shown, or may also be aligned along the X-axis direction. Therefore, the plurality of pouch-type battery cells 110 are arranged in the front-rear and horizontal directions within the battery pack 10, but may also be arranged in multiple rows in the front-rear and horizontal directions.

[0107] The sidewall 500 may be configured so that at least one side is larger than the cell unit 100. For example, as shown in FIG. 3, the length L1 of the sidewall 500 in the front-to-rear direction may be configured to be greater than the length L2 of the cell unit 100 in the front-to-rear direction. Alternatively, the height H1 of the sidewall 500 in the up-to-down direction may be configured to be greater than the height H2 of the cell unit 100 in the up-to-down direction. In this case, external impacts and pressures may be transmitted only to the sidewall 500 and not to the cell unit 100, or the amount of heat transfer may be reduced.

[0108] The sidewall 500 may be made of a metal material that can ensure mechanical rigidity, such as aluminum. In this case, the sidewall 500 may dissipate heat generated from the cell unit 100 to the outside, thereby improving the cooling performance of the battery pack 10. Alternatively, the sidewall 500 may be made of a material such as steel to increase mechanical strength. Alternatively, the sidewall 500 may be made of other materials, such as polymer, as long as a certain level of mechanical strength can be ensured. The sidewall 500 may also be made of a material that combines aluminum and polymer synthetic resin using insert molding.

[0109] The sidewalls 500 may be located at both ends in the stacking direction of the cell unit 100. For example, referring to Figures 2 and 3, when a number of cell units 100 are stacked in the left-right direction, the sidewalls 500 may be provided at the left and right ends of the cell unit stack 300.

[0110] Here, the two sidewalls 500 located at both ends in the stacking direction of the cell unit 100 may have protruding portions provided at different positions on the outer surfaces. This configuration will be described in more detail with reference to Figs. 8 to 12.

[0111] Fig. 8 is a perspective view schematically illustrating the configuration of the right end of a cell block according to another embodiment of the present invention. Fig. 9 is a perspective view schematically illustrating the configuration of the left end of a cell block according to another embodiment of the present invention. Figs. 10 and 11 are front views schematically illustrating the coupling configuration of sidewalls when two cell blocks are arranged adjacent to each other. Fig. 12 is a perspective view schematically illustrating a configuration in which sidewalls are coupled between two adjacent cell blocks to form a vent channel.

[0112] First, referring to Fig. 8, a sidewall (hereinafter referred to as a right wall or a first sidewall) 500a provided at the right end of the cell unit stack 300 in the left-right direction along the stacking direction of the cell units 100 may have a protrusion formed on the lower part of the main body 510a that protrudes outward (e.g., toward the right) as indicated by P1. Then, referring to Fig. 9, a sidewall (hereinafter referred to as a left wall or a second sidewall) 500b provided at the left end of the cell unit stack 300 may have a protrusion formed on the upper part of the main body 510b that protrudes outward (e.g., toward the left) as indicated by P2. Furthermore, a protrusion formed on the second sidewall 500b, which is the left wall, may be provided on the main body 510b that protrudes outward (e.g., toward the left) at the rear as indicated by P3.

[0113] 8 shows the right end and FIG. 9 shows the left end of one cell block 600. Therefore, when multiple cell blocks 600 are arranged adjacent to each other, the first sidewall 500a, which is the right wall, and the second sidewall 500b, which is the left wall, of different cell blocks 600 may face each other, and in this case, the protrusions P1 to P3 of the first sidewall 500a and the second sidewall 500b may be located at different positions in the horizontal or vertical direction so as not to interfere with each other.

[0114] For example, as shown in FIG. 10, by moving the second cell block 600b toward the first cell block 600a, the sidewalls 500a, 500b between the two adjacent cell blocks (the first cell block 600a and the second cell block 600b) can be adjacent to each other, or even bonded to each other, as shown in FIG. 11. That is, when the first cell block 600a and the second cell block 600b are arranged adjacent to each other as shown in FIGS. 10 and 11, the protrusion P1 on the first sidewall 500a of the first cell block 600a and the protrusions P2, P3 on the second sidewall 500b of the second cell block 600b do not collide with each other. Furthermore, the protrusion P1 on the first sidewall 500a can contact or be bonded to the second sidewall 500b. The protrusions P2 and P3 of the second sidewall 500b may contact or be joined to the first sidewall 500a.

[0115] According to this configuration of the present invention, the first cell block 600a and the second cell block 600b have a structure in which they fit together, thereby reducing the space occupied by an array of multiple cell blocks 600 and improving the connectivity between them.

[0116] In particular, when multiple cell blocks 600 are adjacent to or coupled to one another, two sidewalls 500 provided in different cell blocks 600 may form a packed beam. For example, in the embodiment shown in FIG. 11, the second sidewall (not shown) of a first cell block 600a may be coupled to the first sidewall (not shown) of another cell block (not shown) adjacent to its left side to form a packed beam. Similarly, the first sidewall (not shown) of a second cell block 600b may be coupled to the second sidewall (not shown) of another cell block (not shown) adjacent to its right side to form a packed beam.

[0117] Furthermore, two sidewalls 500 may be configured to have an empty space therebetween when adjacent to each other. For example, in the embodiment shown in FIG. 11, when the first sidewall 500a of the first cell block 600a and the second sidewall 500b of the second cell block 600b are joined together, an empty space may be formed therebetween, as indicated by S.

[0118] In particular, such an empty space may be defined by the protrusions P1-P3 and the main bodies 510a, 510b of the sidewalls 500a, 500b, and is defined by two adjacent sidewalls 500. For example, referring to the embodiment of FIGS. 8-11, the main body 510a and the protrusion P1 of the first sidewall 500a of the first cell block 600a may define the left and bottom sides of the internal space indicated by S. Furthermore, the main body 510b and the protrusions P2 and P3 of the second sidewall 500b of the second cell block 600b may define the right, top, and rear sides of the internal space indicated by S.

[0119] Furthermore, the internal space S defined by the sidewalls 500 provided in the two adjacent, different cell blocks 600a, 600b can function as a heat insulating layer, thereby preventing or suppressing the propagation of heat, flames, and the like between the cell blocks 600a, 600b.

[0120] Furthermore, the two sidewalls 500 may be configured to form a vent channel through an internal space S formed adjacent to each other. That is, the internal space S formed by the two sidewalls 500 may function as a vent channel. For example, referring to FIG. 12 , when a first cell block 600a and a second cell block 600b are arranged adjacent to each other and the first sidewall 500a of the first cell block 600a and the second sidewall 500b of the second cell block 600b are coupled to each other, an empty space is formed therein, and this empty space may be formed as a vent channel.

[0121] Pouch-type battery cells 110 have advantages such as being lightweight, having a low risk of electrolyte leakage, and being flexible in shape, allowing for the realization of secondary batteries with the same capacity in smaller volumes and masses. However, ensuring safety is an important issue due to the risk of explosion if they overheat. Overheating of pouch-type battery cells 110 can occur for various reasons, including when an overcurrent exceeds a certain limit and flows through the pouch-type battery cell 110. When an overcurrent flows, the pouch-type battery cell 110 generates heat due to Joule heat, causing a rapid rise in the internal temperature of the pouch-type battery cell 110. This rapid rise in temperature can cause a decomposition reaction of the electrolyte, resulting in the generation of gas. This increases the internal pressure of the pouch exterior material, causing swelling, a type of expansion phenomenon, which can lead to serious problems such as secondary battery explosion. When gas is generated inside the pouch-type battery cell 110 due to not only such an overcurrent but also exposure to high temperatures, external impact, etc., it is necessary to effectively discharge the gas to ensure the safety of the secondary battery. Discharging gas generated inside a secondary battery to the outside is called venting. When vent gas is discharged from the pouch-type battery cell 110 included in the battery pack 10 according to an embodiment of the present invention, the vent gas can be discharged through the vent channel to ensure the safety of the secondary battery.

[0122] Specifically, when vent gas or the like is generated in the first cell block 600a or the second cell block 600b, the generated gas can flow into the space partitioned by the sidewall 500, as indicated by S in Fig. 12. Such vent gas or the like flows along the internal space S formed by the sidewall 500, and can be discharged to the outside, as indicated by the arrow in Fig. 12.

[0123] For this reason, the two side walls 500 may be configured so that a specific portion thereof can be opened when the two side walls 500 are joined together. For example, as shown in Figures 8 to 12, the front side of the side walls 500 may be configured so that the front side can be opened when the side walls 500 are joined together.

[0124] Therefore, vent gas from the first cell block 600a or the second cell block 600b that flows into the vent channel flows along the vent channel as shown by the arrows in FIG. 12 and can be discharged to the outside through the opening. For example, if vent gas is generated due to thermal runaway or the like in a pouch-type battery cell 110 housed inside the cell cover 200, the generated vent gas can move in the front-to-rear direction (in other words, the longitudinal direction) through the internal space S defined by the sidewall 500. This prevents an increase in the internal pressure of the cell cover 200 and enables efficient vent control, such as guiding the discharge direction of the vent gas. In the configurations shown in FIGS. 8 to 12, the front portion of the sidewall 500 where the protrusion P3 is not provided can function as an outlet for the vent channel.

[0125] As described above, according to one embodiment of the present invention, gas and the like discharged from the pouch-type battery cell 110 can be smoothly discharged to the outside. Furthermore, according to one embodiment of the present invention, the discharge direction of gas and flames discharged from the pouch-type battery cell 110 can be controlled. Therefore, the propagation of thermal runaway between adjacent battery cells can be effectively prevented.

[0126] On the other hand, since the sidewall 500 does not include the protrusion P3, the internal space S defined by the sidewall 500 may be configured to be open at both the front and rear portions. Although the present embodiment has been described assuming that the protrusion P3 is provided on the second sidewall 500b of the second cell block 600b, the protrusion P3 may be formed on the first sidewall 500a of the first cell block 600a so as to protrude outward (e.g., toward the right). Although the present embodiment has been described assuming that the protrusion P3 is formed on the rear of the sidewall 500 so as to protrude outward, the protrusion P3 may also be provided on the front of the sidewall 500.

[0127] On the other hand, when the space between the sidewalls 500 of the adjacent cell blocks 600 functions as a vent channel, the sidewalls 500 may be formed with inlet holes for allowing the vent gas of the cell units 100 to flow into the vent channel.

[0128] For example, as indicated by H in Figures 8 and 10 to 12, an inlet hole may be formed in the sidewall 500. For example, such an inlet hole H may be located on the upper side of the sidewall 500 and formed in a shape that penetrates from the cell unit 100 side toward the outside. Preferably, the sidewall 500 protrudes upward beyond the cell unit stack 300, and the inlet hole H is formed in the protruding portion of the sidewall 500. Therefore, vent gas generated in the cell unit 100 can pass through the inlet hole H and flow into the vent channel.

[0129] 8 and 10 to 12, the inlet hole H is shown only in the first sidewall 500a of the cell block 600. However, it goes without saying that an inlet hole may also be formed in the second sidewall 500b. Therefore, when the first cell block 600a and the second cell block 600b are arranged adjacent to each other and the first sidewall 500a of the first cell block 600a and the second sidewall 500b of the second cell block 600b are coupled to each other, the inlet hole of the first cell block 600a and the inlet hole of the second cell block 600b may be positioned facing each other, and may be positioned at different positions in the horizontal or vertical direction. In this case, vent gases, etc., that flow into the vent channel through the inlet hole of the first cell block 600a can be prevented from flowing back into the cell unit 100 of the second cell block 600b through the inlet hole of the second cell block 600b.

[0130] Furthermore, as shown in FIG. 1 , the battery pack 10 according to the present invention may further include a control module 700 accommodated in the internal space of the pack case 400. The control module 700 may include a battery management system (BMS). The control module 700 may be mounted in the internal space of the pack case 400 and configured to generally control the charging and discharging operations and data transmission and reception operations of the pouch-type battery cells 110. The control module 700 may be arranged in units of packs rather than in units of modules. More specifically, the control module 700 may be configured to control the charging and discharging state, power state, and performance state of the pouch-type battery cells 110 using the pack voltage and pack current. The control module 700 estimates the state of the pouch-type battery cells 110 in the battery pack 10 and manages the battery pack 10 using the estimated state information. For example, the control module 700 estimates and manages state information of the battery pack 10, such as the state of charge (SOC), state of health (SOH), maximum input / output power allowance, and output voltage of the battery pack 10. Such status information can be used to control the charging or discharging of the battery pack 10, and can also be used to estimate when the battery pack 10 should be replaced.

[0131] The battery pack 10 according to the present invention may further include a battery disconnect unit (BDU) (not shown). The battery disconnect unit may be configured to control the electrical connection of the battery cells to manage the power capacity and functions of the battery pack 10. To this end, the battery disconnect unit may include a power relay, a current sensor, a fuse, etc. The battery disconnect unit is also a component that is arranged on a pack-by-pack basis rather than on a module-by-module basis, and various disconnect units known at the time of filing of the present invention may be used.

[0132] In addition, the battery pack 10 according to the present invention may further include various battery pack components known at the time of filing of the present invention. For example, the battery pack 10 according to an embodiment of the present invention may further include a manual service disconnector (MSD) that allows an operator to manually remove a service plug to cut off power. The battery pack 10 may also further include a flexible bus bar or cable for connecting at least one cell unit block to each other.

[0133] The two sidewalls 500 located at both ends in the stacking direction of the cell unit 100 can be provided with protruding portions on the outer surfaces at positions symmetrical to each other. This type of configuration will be further described with reference to Figs. 13 to 15.

[0134] Fig. 13 is a perspective view showing a sidewall coupled to a right end of a cell block according to another embodiment of the present invention. Fig. 14 is a perspective view showing a sidewall coupled to a left end of a cell block according to another embodiment of the present invention. Fig. 15 is a front view schematically showing the coupling configuration of the sidewalls shown in Figs. 13 and 14 when two cell blocks are arranged adjacent to each other according to another embodiment of the present invention.

[0135] 13, the first sidewall 500a provided at the right end of the cell unit stack 300 in the left-right direction along the stacking direction of the cell units 100 may have protrusions formed on the upper and lower parts of the main body 510a that protrude outward (for example, toward the right) as shown by P1'. Then, referring to Fig. 14, the second sidewall 500b provided at the left end of the cell unit stack 300 may have protrusions formed on the upper and lower parts of the main body 510b that protrude outward (for example, toward the left) as shown by P2'.

[0136] When multiple cell blocks 600 are arranged adjacent to each other, the first sidewalls 500a and second sidewalls 500b of different cell blocks 600 may face each other, and in this case, the protrusions P1' and P2' of the first sidewalls 500a and second sidewalls 500b may be located symmetrically to each other.

[0137] 15, when the first cell block 600a and the second cell block 600b are positioned adjacent to each other, the first sidewall 500a of the first cell block 600a and the second sidewall 500b of the second cell block 600b can come into contact with each other and can even be bonded to each other. The protrusion P1' provided on the first sidewall 500a of the first cell block 600a and the protrusion P2' provided on the second sidewall 500b of the second cell block 600b can come into contact with each other and be bonded to each other.

[0138] In this case, the shapes of the first sidewall 500a and the second sidewall 500b may be completely the same. Therefore, sidewalls 500 of the same shape can be prepared together and then coupled to both ends of the cell unit stack 300 to manufacture the cell block 600. This eliminates the need to consider the coupling direction when coupling sidewalls of different shapes, thereby facilitating a smooth assembly process. In addition, in this embodiment, the sidewalls 500 may be configured so that both the front and rear sides are open when coupled.

[0139] On the other hand, the protrusion P1' of the first sidewall 500a may be an extension of the main body 510a of the first sidewall 500a that is bent so as to be perpendicular to the surface direction of the main body 510a of the first sidewall 500a, and the protrusion P1' of the second sidewall 500b may be an extension of the main body 510b of the second sidewall 500b that is bent so as to be perpendicular to the surface direction of the main body 510b of the second sidewall 500b.

[0140] In this case, the sidewall 500 may be formed by bending a metal plate having a plate-like structure. That is, similar to the cell cover 200, the sidewall 500 may be formed by bending a single plate into a bent shape. The sidewall 500 may be formed to include the protrusion P1' by bending both ends of a single plate in the same direction. According to this embodiment of the present invention, the manufacture of the sidewall 500 is further simplified.

[0141] The battery pack 10 according to one embodiment of the present invention can be applied to various devices. Typical examples of such devices include electric motorcycles, electric vehicles, and hybrid vehicles, but the present invention is not limited to these. The battery pack 10 can be suitably used as a battery pack for electric vehicles. It can also be used as an energy source for an energy storage system (ESS).

[0142] FIG. 16 is a diagram showing a schematic configuration of a vehicle according to one embodiment of the present invention.

[0143] 16, an automobile V according to an embodiment of the present invention may include the battery pack 10 according to an embodiment of the present invention described above. Here, the automobile V may include a predetermined automobile that uses electricity as a driving source, such as an electric automobile or a hybrid automobile. Furthermore, the automobile V may further include various other components included in an automobile, such as a body and a motor, in addition to the battery pack 10 according to the present invention.

[0144] The battery pack 10 can be disposed at a predetermined position within the vehicle V. The battery pack 10 can be used as an electric energy source that provides driving force to a motor of the electric vehicle to drive the vehicle V. In this case, the battery pack 10 has a high nominal voltage of 100 V or more.

[0145] The battery pack 10 may be charged or discharged by an inverter in response to the driving of the motor and / or the internal combustion engine. The battery pack 10 may be charged by a regenerative charging device coupled to a brake. The battery pack 10 may be electrically connected to the motor of the vehicle V via the inverter.

[0146] Although the present invention has been described above using limited embodiments and drawings, the present invention is not limited to these, and it goes without saying that various modifications and variations can be made by a person having ordinary knowledge in the technical field to which the present invention pertains within the technical spirit of the present invention and the scope of equivalents of the claims. [Explanation of symbols]

[0147] 10: Battery pack 100: Cell unit 110: Pouch-type battery cell 200: Cell cover 300: Cell unit stack 400: Pack case 500:Sidewall 600: Cell Block

Claims

1. a cell unit stack in which a large number of cell units are stacked; a pack case that houses the cell unit stack in an internal space; sidewalls positioned at ends of the cell unit stack in the internal space of the pack case and configured to support the pack case; Including, the large number of cell units are stacked in at least one direction in the cell unit stack; The cell unit includes one or more pouch-type battery cells and a cell cover configured to at least partially enclose the pouch-type battery cells, the sidewalls are located at both ends of the cell unit in the stacking direction, The two side walls located at both ends in the stacking direction of the cell units have protrusions on their outer surfaces that are provided at different positions or symmetrical to each other.

2. The battery pack according to claim 1 , wherein the sidewalls support the pack case in a horizontal direction perpendicular to a stacking direction of the cell units.

3. 2. The battery pack according to claim 1, wherein the pack case includes a lower plate and a plurality of side plates standing upright upward from the lower plate, and the sidewalls are interposed between the different side plates of the pack case.

4. The battery pack according to claim 3 , wherein both ends of the side wall are respectively coupled and fixed to different side plates of the pack case.

5. A cell unit stack in which a large number of cell units are stacked; a pack case that houses the cell unit stack in an internal space; sidewalls positioned at ends of the cell unit stack in the internal space of the pack case and configured to support the pack case; Including, the large number of cell units are stacked in at least one direction in the cell unit stack; The cell unit includes one or more pouch-type battery cells and a cell cover configured to at least partially enclose the pouch-type battery cells, the pack case includes a lower plate and a plurality of side plates standing upright upward from the lower plate, the sidewalls being interposed between the different side plates of the pack case, The pack case further includes an upper plate coupled onto the side plate, and upper and lower ends of the side walls are in contact with the upper and lower plates, respectively.

6. 4. The battery pack according to claim 3, wherein the pack case further includes a center beam between different side plates, and the side walls are configured to provide support between the side plates and the center beam.

7. The battery pack according to claim 1 , wherein the sidewall is configured so that at least one side thereof is larger than the cell unit.

8. The battery pack according to claim 5 , wherein the sidewalls are located at both ends of the cell units in the stacking direction.

9. The battery pack according to claim 8 , wherein the two side walls located at both ends in the stacking direction of the cell units have protrusions on their outer surfaces at different positions or at positions symmetrical to each other.

10. 2. The battery pack according to claim 1, wherein a plurality of the cell unit stacks are included along the stacking direction of the cell units, and a sidewall of any one of the cell unit stacks and a sidewall of another of the cell unit stacks are adjacent to each other, forming an internal space defined by the two sidewalls.

11. The battery pack according to claim 10 , wherein the internal space extends in a horizontal direction perpendicular to the stacking direction of the cell units to form a vent channel.

12. the two sidewalls include a first sidewall provided at a right end of the cell unit stack in a left-right direction along the stacking direction of the cell units, and a second sidewall provided at a left end of the cell unit stack, the first sidewall has a protrusion formed at an upper or lower part thereof so as to protrude toward the right, and the second sidewall has a protrusion formed at a lower or upper part thereof so as to protrude toward the left, The battery pack according to claim 10 , wherein a first sidewall of any one of the cell unit stacks and a second sidewall of another of the cell unit stacks are adjacent to each other to form the internal space.

13. The battery pack according to claim 12 , wherein the protrusions of the first sidewall and the protrusions of the second sidewall are positioned at different positions in the horizontal or vertical direction so as not to interfere with each other.

14. 13. The battery pack according to claim 12, wherein the protrusion of the first sidewall is an extension of the main body of the first sidewall that is bent so as to be perpendicular to a surface direction of the main body of the first sidewall, and the protrusion of the second sidewall is an extension of the main body of the second sidewall that is bent so as to be perpendicular to a surface direction of the main body of the second sidewall.

15. 15. The battery pack of claim 14, wherein a protrusion of the first sidewall contacts or is coupled to the second sidewall, a protrusion of the second sidewall contacts or is coupled to the first sidewall, or a protrusion of the first sidewall contacts or is coupled to a protrusion of the second sidewall.

16. The battery pack according to claim 12 , wherein one of the first side wall and the second side wall is further provided with a protrusion formed to protrude outward in a forward or rearward direction.

17. The battery pack according to claim 10 , wherein the sidewalls protrude above the cell unit stack, and inlet holes are formed in the protruding portions of the sidewalls.

18. a cell unit stack in which a large number of cell units are stacked; a sidewall located at an end of the cell unit stack; Including, the large number of cell units are stacked in at least one direction in the cell unit stack; The cell unit includes one or more pouch-type battery cells and a cell cover configured to at least partially enclose the pouch-type battery cells, the sidewalls are located at both ends of the cell unit in the stacking direction, The cell block has two side walls located at both ends of the cell unit in the stacking direction, each of which has protrusions on its outer surface at different positions or at positions symmetrical to each other.

19. A motor vehicle comprising a battery pack according to any one of claims 1 to 17.

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