Battery module and battery pack including same

Abstract

The battery module according to the present invention includes a battery cell assembly in which two or more battery cells, each having electrode leads formed on both ends in the longitudinal direction, are arranged in a row in the longitudinal direction to form a longitudinal unit cell, and the longitudinal unit cells are stacked in two or more rows in the thickness direction of the battery cell, a terminal bus bar connected to the battery cells included in the battery cell assembly, a venting plate installed between the rows of the longitudinal unit cells and having a gas venting channel formed therein, and a module case in which the battery cell assembly and the venting plate are housed.The battery cells of the battery cell assembly, except for the battery cell connected to the terminal bus bar, have electrode leads directly connected to each other and a venting hole communicating with the gas venting channel formed in the module case.

Description

[Technical field]

[0001] The present invention relates to a battery module.

[0002] More particularly, the present invention relates to a battery module that is configured to be expandable, and that simplifies the electrical connection structure of battery cell assemblies included in the battery module and is capable of discharging gas within the module.

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

[0004] This application claims the benefit of priority based on Korean Patent Application No. 10-2021-0155941 dated November 12, 2021, and all contents disclosed in the documents of that Korean patent application are incorporated herein by reference. [Background technology]

[0005] In recent years, rechargeable secondary batteries have been widely used as energy sources for wireless mobile devices. Secondary batteries are also attracting attention as energy sources for electric vehicles and hybrid electric vehicles, which are proposed as a solution to address air pollution caused by existing gasoline and diesel vehicles that use fossil fuels. Therefore, the types of applications that use secondary batteries are becoming increasingly diverse due to the advantages of secondary batteries, and secondary batteries are expected to be applied to many more fields and products in the future.

[0006] In addition, there is an increasing demand for battery modules housing a number of secondary batteries electrically connected in series or parallel and battery packs including the battery modules as power sources for energy storage systems (ESS) and electric vehicles.

[0007] Such a battery module or battery pack includes an external housing made of a metal material for storing and protecting a plurality of secondary batteries from external impacts.

[0008] 1 is a partial perspective view of a conventional battery module 1. As shown in the figure, the battery module 1 has a battery cell assembly, formed by stacking several tens of battery cells, housed in a module case 2. In addition, a plurality of inter-bus bars 3 are installed at the front end of the module to electrically connect the battery cells of the battery cell assembly.

[0009] Such a conventional battery module has the following problems.

[0010] First, since single battery cells are stacked only in the thickness direction, the space utilization and design freedom of the battery cell arrangement are low. Therefore, there is a limit to bundling such modules to form a battery pack. In other words, it is not easy to form a battery module or battery pack to fit a limited space such as an automobile or various spaces. In addition, since many battery cells (approximately several tens of cells) are stacked in one module, if one battery cell catches fire, the flame is likely to spread to other battery cells, and there is a risk that the module will burn down in a short period of time.

[0011] Secondly, since the busbar frame is installed at the front end of the module case 2 and the inter-busbars 3 connected to each battery cell are installed on the busbar frame, the busbar frame must be formed in a complex shape to provide space for installing the busbars. Also, the number of inter-busbars 3 required increases according to the number of battery cells, which causes an increase in costs.

[0012] Thirdly, since there is no route for safely discharging gas from the module to the outside, if an internal venting phenomenon occurs, it will cause a rise in temperature inside the module, which will pose a high risk of fire and explosion.

[0013] Therefore, there is a demand for the development of battery module-related technology that not only increases the design freedom of battery modules and battery packs, but also simplifies the connection structure of the battery cells while efficiently discharging gas inside the module and preventing flame propagation. [Prior art documents] [Patent documents]

[0014] [Patent Document 1] Korean Patent No. 10-2259416 Summary of the Invention [Problem to be solved by the invention]

[0015] The present invention has been made to solve the above problems, and an object of the present invention is to provide an expandable battery module in which battery cells are connected in the lengthwise direction as well as in the thickness direction to improve space utilization of a battery module and a battery pack.

[0016] Another object of the present invention is to provide a battery module having a structure that can reduce assembly steps and manufacturing costs by simply connecting battery cells electrically without the need for inter-bus bars.

[0017] Another object of the present invention is to provide an expandable battery module having a gas venting structure capable of efficiently discharging gas generated inside the battery module. [Means for solving the problem]

[0018] To solve the above problems, a battery module according to the present invention includes a battery cell assembly in which two or more battery cells, each having electrode leads formed on both ends in the longitudinal direction, are arranged in a row in the longitudinal direction to form a longitudinal unit cell, and the longitudinal unit cells are stacked in two or more rows in the thickness direction of the battery cell, a terminal bus bar connected to the battery cells included in the battery cell assembly, a venting plate installed between the rows of the longitudinal unit cells and having a gas venting channel formed therein, and a module case in which the battery cell assembly and the venting plate are housed.The battery cells of the battery cell assembly, except for the battery cell connected to the terminal bus bar, have electrode leads directly connected to each other, and a venting hole communicating with the gas venting channel is formed in the module case.

[0019] As an example, the terminal bus bar may be coupled to an electrode lead of a battery cell located at a front end or a rear end in the longitudinal direction of the battery cell assembly.

[0020] Specifically, electrode leads of battery cells facing each other in the longitudinal direction of the longitudinal unit cell may be connected to each other by welding, and electrode leads of battery cells included in an adjacent row of longitudinal unit cells at a longitudinal front end or a longitudinal rear end of the battery cell assembly to which a terminal bus bar is not connected may be bent in a thickness direction of the battery cell and welded to each other.

[0021] As a specific example, the module case may include a front end plate and a rear end plate covering the front and rear ends of the battery cell assembly, and the terminal bus bar may be coupled to the front end plate or the rear end plate.

[0022] As another example, the terminal bus bar may be coupled to an electrode lead of a battery cell that is longitudinally opposed to the longitudinal unit cell.

[0023] Specifically, battery cells facing each other in the longitudinal direction of a row of longitudinal unit cells that are not coupled to the terminal bus bar may be connected by welding their electrode leads to each other, and the electrode leads of battery cells included in longitudinal unit cells of adjacent rows at the front and rear ends in the longitudinal direction may be bent in the thickness direction of the battery cells and welded to each other.

[0024] As an example, the same number of rows of longitudinal unit cells may be arranged on each side of the venting plate based on the longitudinal direction of the battery cells, and the venting plate may be installed to extend in the longitudinal direction of the battery cells across the front and rear ends of the module case.

[0025] As a specific example, the gas venting channel may include a longitudinal channel extending in a longitudinal direction of the venting plate, and a width channel communicating with the longitudinal channel and opening to the outside of the venting plate, and the width channel may be formed at a position corresponding to a midpoint between electrode leads at both ends of a battery cell included in the longitudinal unit cell.

[0026] In addition, the venting plate may include a venting through hole communicating with the longitudinal channel at a position corresponding to a gas pocket connected to an electrode lead of a battery cell included in the longitudinal unit cell.

[0027] As an example, the venting plate may include a heat propagation prevention plate that is installed perpendicular to the body portion at a position corresponding to between a body portion extending in a longitudinal direction of the battery cell and an electrode lead of a battery cell facing the longitudinal direction of the longitudinal unit cell.

[0028] Specifically, lead coupling through-holes through which electrode leads of the battery cells pass and are supported may be formed in the front and rear ends of the body of the venting plate and in the heat propagation prevention plate.

[0029] A battery pack according to another aspect of the present invention may include a battery module stack formed by stacking a plurality of the battery modules in at least one of a length direction and a thickness direction of the battery cell. Effect of the Invention

[0030] According to the present invention, an expandable battery module can be obtained in which battery cells are connected in the lengthwise direction as well as in the thickness direction to improve space utilization of the battery module and the battery pack.

[0031] Furthermore, the present invention can realize a simple electrical connection structure of battery cells that is suitable for such an expandable battery module.

[0032] In addition, the present invention can improve the safety of the battery module by implementing a gas venting structure capable of efficiently discharging internally generated gas in the expandable battery module. [Brief description of the drawings]

[0033] [Figure 1] FIG. 1 is a partial perspective view of a conventional battery module. [Diagram 2] 1 is an exploded perspective view of a battery module according to an embodiment of the present invention; [Diagram 3] 3A and 3B are a perspective view and a plan view showing a coupling relationship of a battery cell assembly which is a component of the battery module of FIG. 2. [Figure 4] 3A and 3B are a perspective view and a front view showing the structure of a ventilation plate included in the battery module of FIG. 2. [Diagram 5] 3 is a perspective view showing a specific coupling relationship of a battery cell assembly of the battery module of the embodiment of FIG. 2. [Figure 6] FIG. 3 is a perspective view showing the appearance of the assembled battery module of FIG. 2. [Figure 7] FIG. 4 is an exploded perspective view of a battery module according to another embodiment of the present invention. [Figure 8] 8 is a plan view showing a coupling relationship of a battery cell assembly which is a component of the battery module of FIG. 7. [Figure 9] 8A and 8B are a perspective view and a front view showing the structure of a ventilation plate included in the battery module of FIG. 7. [Figure 10] 8 is a perspective view showing a specific coupling relationship between battery cells facing each other in the longitudinal direction of a longitudinal unit cell according to the embodiment of FIG. 7; FIG. [Figure 11] 8 is a perspective view showing a specific coupling relationship between battery cells located at the ends of a longitudinal unit cell in the embodiment of FIG. 7. FIG. [Figure 12] FIG. 8 is a perspective view showing the appearance of the assembled battery module of FIG. 7. [Figure 13] FIG. 1 is a schematic diagram of a battery pack including a battery stack constructed with a battery module of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0034] [Explanation of symbols] 10: Battery cell 11, 12: Electrode lead 100: Battery cell assembly 110: Longitudinal unit cell 200, 200': Terminal bus bar (first embodiment) 210, 210': Terminal bus bar (second embodiment) 220, 220': Terminal busbar support block 300: Venting plate 310: Main body 311: Gas venting channel 311a: Longitudinal channel 311b: Width direction channel W: Bulkhead O: Channel exit E: Channel entrance 312: Venting hole 313: Lead connection through hole 320: Heat propagation prevention plate 321: Lead connection through hole 400: Module case 410: C-shaped wall 411: Venting Hall 420: I-shaped wall 430, 430': Front end plate 440, 440': Rear end plate 1000, 1000': Battery module 1100: Battery module stack 2000: Battery pack 2100: Battery pack case

[0035] The present invention will be described in detail below. Before that, the terms and words used in the specification and claims should not be interpreted limitedly to their ordinary or dictionary meanings, but should be interpreted as meanings and concepts that are consistent with the technical idea of ​​the present invention, based on the principle that the inventor can appropriately define the concepts of the terms in order to best describe his own invention.

[0036] As used throughout the present specification, terms such as "comprise" and "have" are intended to specify the presence of features, numbers, steps, operations, components, parts, or combinations thereof set forth in the specification, but should be understood as not precluding the presence or additional possibility of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0037] Furthermore, when a layer, film, region, plate, or other part is described as being "on" another part, this includes not only the case where it is "directly on" the other part, but also the case where there is another part in between. Conversely, when a layer, film, region, plate, or other part is described as being "under" another part, this includes not only the case where it is "directly under" the other part, but also the case where there is another part in between. Furthermore, in the specification of the present invention, being "on" can include not only the case where it is located at the top, but also the case where it is located at the bottom.

[0038] The battery module according to the present invention includes a battery cell assembly in which two or more battery cells, each having electrode leads formed on both ends in the longitudinal direction, are arranged in a row in the longitudinal direction to form a longitudinal unit cell, and the longitudinal unit cells are stacked in two or more rows in the thickness direction of the battery cell, a terminal bus bar connected to the battery cells included in the battery cell assembly, a venting plate installed between the rows of the longitudinal unit cells and having a gas venting channel formed therein, and a module case in which the battery cell assembly and the venting plate are housed.The battery cells of the battery cell assembly, except for the battery cell connected to the terminal bus bar, have electrode leads directly connected to each other and a venting hole communicating with the gas venting channel formed in the module case.

[0039] According to an installation position of a terminal bus bar included in a battery module of the present invention, the following embodiments can be classified.

[0040] (First embodiment) FIG. 2 is an exploded perspective view of a battery module according to one embodiment of the present invention, FIG. 3 is a perspective view and a plan view showing the coupling relationship of a battery cell assembly, which is a component of the battery module of FIG. 2, and FIG. 4 is a perspective view and a front view showing the structure of a venting plate included in the battery module of FIG. 2.

[0041] As shown in Fig. 2, the present invention includes a battery cell assembly 100 including a longitudinal unit cell 110, and a module case 400 in which the battery cell assembly 100 is housed. In Fig. 2, based on a typical pouch-type battery cell 10 having electrode leads 11, 12 formed at both ends and extended long in the longitudinal direction, the X direction is the longitudinal direction of the battery cell 10 or the module case 400, the Y direction is the thickness direction of the battery cell 10 or the module case 400 (stacking direction of the battery cells), and the Z direction is the up-down direction.

[0042] The battery cell 10 of the present invention is intended for a battery cell in which electrode leads 11, 12 are formed on both longitudinal ends (so-called bidirectional battery cell (bidirectional pouch cell)). With this configuration, the positive electrode lead 11 and the negative electrode lead 12 are respectively formed and led out from both ends of a single battery cell 10, eliminating interference between the electrode leads and allowing the area of ​​the electrode leads to be increased, making it easier to connect the electrode leads to bus bars.

[0043] The battery cell assembly 100 of the present invention includes a bundle of battery cells, each of which is a longitudinal unit cell 110, in which two or more such bidirectional battery cells 10 are arranged in a row in the longitudinal direction and the electrode leads 11, 12 of the battery cells 10 facing each other in the longitudinal direction are electrically connected to each other. In Figs. 2 and 3, two battery cells 10 are connected in the longitudinal direction to form the longitudinal unit cell 110, but two or more battery cells may be connected in the longitudinal direction. As long as the space of the battery pack in which the battery module case 400 or the battery module 1000 is installed is permitted, the number of battery cells 10 connected in the longitudinal direction is not limited in principle. However, since the space of the battery module 1000 or the battery pack that can be actually installed in an automobile or the like is limited, it is preferable to connect about two to four battery cells 10 in the longitudinal direction. In addition, the number of battery cells 10 connected in the longitudinal direction may be changed depending on the size (length) of the battery cells 10 to be connected. As described above, in this specification, a combination of two or more battery cells 10, each having electrode leads 11, 12 formed on both ends in the longitudinal direction, arranged in a row is referred to as a longitudinal unit cell 110.

[0044] The battery cell assembly 100 included in the battery module 1000 of the present invention is formed by stacking the longitudinal unit cells 110 in two or more rows in the thickness direction (Y direction) of the battery cell 10. The number of rows in which the longitudinal unit cells 110 are stacked also depends on the allowable space of the battery module 1000 and the battery pack, the size of the battery cell 10, and the like. In addition, the number of the battery cells 10 in the longitudinal direction and the number of rows can be determined in consideration of the required capacity of the required electric device. In this way, the present invention can adjust the number of battery cells in the longitudinal direction and the number of rows of the battery cell assembly 100 housed in the module case 400, thereby improving the design freedom. In addition, if the battery cell assemblies 100 are stacked in tens of pieces as in the conventional method, for example, by stacking about 2 to 4 pieces in the longitudinal direction and about 2 to 6 rows in the thickness direction of the battery cell, the battery cell assembly 100 can be configured more compactly. Also, by accommodating the battery cell assemblies 100 each composed of a small number of battery cells 10 in separate module cases 400 and stacking the battery modules 1000 including the module cases 400 in the longitudinal or thickness direction of the battery cells 10 like Lego blocks, a battery pack can be freely configured in consideration of the space in which the battery modules 1000 are installed or the installation space of the battery pack. For example, by stacking the battery modules 1000 in the longitudinal direction, the same effect can be achieved without connecting the battery cells of the longitudinal unit cells 110 further in the longitudinal direction. This allows individual battery modules (unit modules) to be configured more compactly. Also, by stacking the battery modules 1000 in the thickness direction of the battery cells as many as necessary, the degree of freedom in design can be improved. In the structure in which several tens of battery cells are stacked in one module case 2 as shown in FIG. 1, it is difficult to configure a battery pack as desired. That is, since the minimum unit of the battery cells included in the battery modules constituting the battery pack is different, the degree of freedom in design of the conventional battery module 1 is inevitably reduced accordingly.

[0045] Also, for example, if a fire occurs in some of the battery cells included in the battery module, the flame is likely to spread to adjacent battery cells in the battery module 1 of Fig. 1. However, in the structure of the battery module 1000 of Fig. 2 or the battery pack 2000 disclosed in Fig. 13 described below, a small number of battery cell assemblies 100 are housed separately in the battery module 1000, so that even if a fire occurs in a battery cell 10 in one battery module 1000, the fire is unlikely to spread to other battery modules 1000.

[0046] As described above, the battery cell assemblies 100 of the present invention are connected in the longitudinal direction and the thickness direction of the battery cells, and each battery cell assembly 100 consisting of a specific number of battery cells 10 is housed in each module case 400. Therefore, since any number of different types of battery packs can be manufactured depending on the stacking (design) method of the battery module 1000 including such battery cell assemblies 100, the battery module 1000 of the present invention can be called an expandable module.

[0047] The battery cell assembly 100 of the present invention shown in Figures 2 and 3 has two battery cells 10 connected in the longitudinal direction, and the longitudinal unit cells 110 are stacked in two rows, forming a so-called 1P4S connected structure, with a total of four battery cells 10 constituting the battery cell assembly 100.

[0048] However, by varying the number of rows of longitudinal unit cells connected in pairs in the longitudinal direction, battery cell assemblies such as 4-row stacking (2P4S), 6-row stacking (3P4S), 8-row stacking (4P4S), etc., with an even number of rows can also be used. Also, structures in which three cells are connected in the longitudinal direction instead of two (1P6S, 2P6S, 3P6S, ...), structures in which four cells are connected (1P8S, 2P8S, 3P8S, ...), and structures in which more than two cells are connected are also possible. In short, it is an advantage of the present invention that the stacking structure of the longitudinal unit cells and battery cell assemblies can be changed in a diverse and scalable manner according to the design requirements of the above-mentioned battery module and battery pack.

[0049] Although not shown, a heat insulating plate or an insulating sheet may be installed between the rows of the longitudinal unit cells 110. In one embodiment of the present invention, a ventilation plate 300 is installed between the rows of the longitudinal unit cells 110 instead of the heat insulating plate.

[0050] The battery module 1000 of the present invention includes terminal bus bars 200, 200' coupled to the battery cells 10 included in the battery cell assembly 100. The terminal bus bars 200, 200' are terminals that can be connected to other adjacent battery modules 1000 or external devices. In this embodiment, the terminal bus bars 200, 200' are coupled to the electrode leads 11, 12 of the battery cells 100 located at the front or rear end of the battery cell assembly 100 in the longitudinal direction.

[0051] 2, in this embodiment, the terminal bus bars 200, 200' are coupled to a front end plate 430 covering the front end of the battery cell assembly 100. Optionally, the terminal bus bars 200, 200' may also be installed at the rear end side of the battery cell assembly 100, in which case the terminal bus bars 200, 200' may be coupled to a rear end plate 440 covering the rear end of the battery cell assembly 100. In FIG. 2, two terminal bus bars 200, 200' are provided on the front end plate 430 according to polarity, and are coupled to the electrode leads 11, 12 of the battery cell 10 located at the front end of the longitudinal unit cell 110 on the rear side of the front end plate 430.

[0052] Among the battery cells 10 in the battery cell assembly 100 of the present invention, adjacent battery cells, excluding the battery cells coupled with the terminal bus bars 200, 200', are characterized in that their electrode leads are directly connected to each other. In other words, by directly connecting the electrode leads to each other without the inter-bus bar used when connecting the electrode leads of conventional battery cells, the electrical connection structure of the battery cells is greatly simplified. The electrode leads 11, 12 can be connected by welding, for example, laser welding, spot welding, or the like.

[0053] FIG. 3 is a diagram that shows a schematic electrical connection relationship of the battery cells 10 of the battery cell assembly 100 of the present embodiment, omitting the illustration of a ventilation plate 300, which will be described later, for convenience of illustration.

[0054] As shown in the perspective view and plan view of Fig. 3, the electrode leads 11, 12 of the battery cells 10 facing each other in a longitudinal unit cell 110 are directly welded and coupled to each other. Also, the electrode leads 11, 12 of the battery cells included in the longitudinal unit cells 110 in the adjacent row at the longitudinal front end or rear end to which the terminal bus bars 200, 200' are not coupled in the battery cell assembly 100 may be bent in the thickness direction of the battery cells and welded to each other. Fig. 3 shows that the electrode leads 11, 12 of the adjacent battery cells at the rear end of the longitudinal unit cells 110 are bent toward each other and coupled to each other because the terminal bus bars 200, 200' are coupled to the front end of the longitudinal unit cells 110. If the electrode leads 11, 12 of the battery cells coupled to the terminal bus bars 200, 200' are electrically connected to each other, a short circuit will occur, so the electrode leads of the adjacent longitudinal unit cells 110 of the terminal bus bars 200, 200' are coupled to two terminal bus bars 200, 200' installed on the front end plate 430. Two terminal bus bars 200, 200' are provided depending on the polarity.

[0055] The battery module 1000 of the present invention also includes a venting plate 300 disposed between the rows of the longitudinal unit cells 110 and having gas venting channels formed therein.

[0056] 2 and 4, and in particular FIG. 4, one embodiment of such a venting plate 300 is illustrated.

[0057] The venting plate 300 is disposed between the rows of the longitudinal unit cells 110, and can prevent the propagation of heat and flame in the thickness direction of the battery cell when a fire occurs inside the battery cell due to overheating. Preferably, the same number of longitudinal unit cells 110 are disposed on both sides of the venting plate 300 based on the longitudinal direction of the battery cell 10. In this embodiment, one longitudinal unit cell 110 is disposed on each of the left and right sides of the venting plate 300. The venting plate 300 is preferably larger than the battery cell 10 so as to cover the entire area of ​​the battery cell as much as possible. That is, the width of the venting plate 300 is preferably large enough to cover the entire width of the battery cell. The length of the venting plate 300 can be extended long in the longitudinal direction of the battery cell across the front and rear ends of the module case 400 to cover the entire longitudinal unit cells 110.

[0058] In particular, the venting plate 300 has a hollow structure in which gas venting channels 311 are formed to allow gas and flame to escape.

[0059] Most of the gas inside the battery module 1000 is generated near the electrode leads of the battery cells 10, and near gas pockets that are terraces between the electrode leads 11 and the battery cell main body when the pouch cell is used as a reference. Therefore, it is preferable that the venting channel 311 has a gas inlet E (venting through holes 312 or an opening communicating therewith) communicating with the inside of the battery module 1000 at a position of the venting plate 300 corresponding to the gas pocket. Referring to FIG. 4, the venting plate 300 has a total of four venting through holes 312 at positions corresponding to the gas pockets of the battery cells included in the battery cell assembly 100, and the venting through holes 312 communicate with the gas venting channel 311.

[0060] In addition, the gas venting channel 311 has an outlet O through which the gas and flame can be discharged. Since the gas and flame flowing in from the gas inlet E corresponding to the gas pocket are hot, the outlet O of the venting channel needs to be far away from the gas inlet E to lower the temperature of the gas and discharge it to the outside. For this reason, the gas venting channel 311 of the present invention has a flow path that extends long from the gas inlet E to the outlet O.

[0061] Specifically, the gas venting channel 311 may include a longitudinal channel 311a extending in the longitudinal direction of the venting plate 300, and a widthwise channel 311b communicating with the longitudinal channel 311a and opening to the outside of the venting plate 300. At this time, it is preferable that the widthwise channel 311b is formed at a position corresponding to a midpoint between electrode leads at both ends of the battery cells included in the longitudinal unit cell 110 when the battery cell assembly is coupled to the venting plate 300. As a result, as shown in FIG 4, gas from a gas pocket near the electrode leads 11 and 12 at the end of the battery cell can move to a position corresponding to the midpoint through the longitudinal channel 311a, and the gas and flames can be easily exhausted from that position through the widthwise channel 311b.

[0062] The gas venting channel, particularly the longitudinal channels 311a, may be formed in a plurality of numbers along the longitudinal direction of the venting plate 300. Referring to the front view of Fig. 4, the venting plate 300 has five longitudinal channels 311a divided by partition walls W. Gas passing through the longitudinal channels 311a may join together in the widthwise channels 311b and be discharged to the outside toward at least one of the upper and lower sides of the venting plate 300 in the width direction.

[0063] Meanwhile, the venting plate 300 of the present embodiment includes a body part 310 extending in the longitudinal direction of the battery cell, and a heat propagation prevention plate 320 installed perpendicular to the body part 310. The heat propagation prevention plate 320 is installed at a position corresponding to between the electrode leads 11, 12 of the battery cells 10 facing each other in the longitudinal direction of the longitudinal unit cell 110. Therefore, the heat propagation prevention plate 320 can block heat propagation between the battery cells 10 arranged in the longitudinal direction of the longitudinal unit cell 110.

[0064] As shown in FIG. 3, the electrode leads 11, 12 of the adjacent battery cells not connected to the terminal bus bar among the battery cells of the battery cell assembly 100 are directly connected to each other. The bending plate 300 includes a separate through hole for connecting with such electrode leads or supporting the connected electrode lead portion. In this embodiment, since two rows of the longitudinal unit cells 110 are provided around the bending plate 300, the lead connection through holes 321 are formed on the left and right sides of the heat propagation prevention plate 320 so that the electrode leads 11, 12 of the battery cells facing each other in the longitudinal direction can pass through and be welded. In addition, the bending plate 300 has a front and rear end through holes 313 through which the electrode leads of the battery cells can pass in order to provide a space for bending and welding the electrode leads 11, 12 of the battery cells 10 at the front or rear end of the longitudinal unit cells 110. The size of the lead connection through hole 313 may be changed in various ways according to the purpose, such as a size that allows easy connection between electrode leads or a size that can support the connected electrode leads.

[0065] The present invention also includes a module case 400 in which the battery cell assembly 100 and the venting plate 300 are housed.

[0066] That is, as shown in Fig. 2, the present invention includes a module case 400 that encases and houses the battery cell assembly 100. The module case 400 has a rectangular parallelepiped structure that is elongated in the longitudinal direction so as to house the battery cell assembly specific to the present invention. In Fig. 2, the module case 400 is formed by combining a C-shaped wall 410 and an I-shaped wall 420, but is not limited thereto. For example, a form in which two C-shaped walls arranged on the left and right or above and below are combined is also possible, and a form in which the upper, lower, left and right cases are each separated and combined by welding, hooking, or a fastening member is also possible.

[0067] In addition, the module case 400 of the present invention includes a front end plate 430 and a rear end plate 440. The front end plate 430 and the rear end plate 440 are respectively coupled to the combined body of the C-shaped wall 410 and the I-shaped wall 420 to close the front and rear of the module. As described above, the terminal bus bars 200, 200' may be coupled to the front end plate 430 or the rear end plate 440, and the electrode leads 11, 12 of the battery cells located at the front end or rear end of the longitudinal unit cell 110 may be connected to the terminal bus bars 200, 200'.

[0068] The module case 400 is characterized in that it has a venting hole 411 at a position communicating with the gas venting channel 311 of the venting plate 300. For example, the venting hole 411 may be formed on the upper or lower surface of the module case 400 at a position where the venting plate 300 of Fig. 4 is connected to the outlet O of the width direction channel 311b which is a part of the gas venting channel 311. Gas and flames within the battery module can be quickly exhausted through the gas venting channel 311 and the venting hole 411 of the module case 400, thereby further improving the safety of the expandable battery module.

[0069] FIG. 5 is a perspective view showing a specific coupling relationship of battery cell assemblies of the battery module of the embodiment of FIG. 2, and FIG. 6 is a perspective view showing the exterior of the assembled battery module of FIG.

[0070] Specifically, FIG. 5 is a perspective view specifically illustrating the electrical connection structure of the battery cell assembly 100 associated with the venting plate 300 in a state in which the module case 400 is not assembled.

[0071] FIG. 5(a) illustrates the connection between the electrode leads of battery cells 10 facing each other in the longitudinal direction corresponding to the middle of a longitudinal unit cell 110, and shows that the electrode leads 11, 12 of the battery cells on both sides are welded and connected through a lead connection through hole 321 formed in a heat propagation prevention plate 320 of a ventilation plate 300.

[0072] 5(b) illustrates the connection between the electrode leads of battery cells located at the ends of the longitudinal unit cells 110 in adjacent rows, and shows that the electrode leads of the battery cells are welded and connected through the lead connection through hole 313 located at the front end of the venting plate 300. In particular, FIG. 5(b) shows a venting through hole 312 (long hole) in the venting plate 300 behind the lead connection through hole 313, and also shows that the venting through hole 312 is in communication with the gas venting channel, specifically the longitudinal channel 311a, through the inlet E.

[0073] 6 shows a state in which the battery cell assembly 100 and the venting plate 300 are housed and assembled in a module case 400, and shows that a front end plate 430 to which terminal bus bars 200, 200' are attached is coupled to the front end of the module case 400. As shown, a venting hole 411 communicating with a gas venting channel 311 of the venting plate 300 in the module is formed at a predetermined position on the upper surface of the module case 400.

[0074] Second embodiment FIG. 7 is an exploded perspective view of a battery module 1000′ according to another embodiment of the present invention, FIG. 8 is a plan view showing the coupling relationship of a battery cell assembly 100, which is a component of the battery module of FIG. 7, and FIG. 9 is a perspective view and a front view showing the structure of a ventilation plate 300 included in the battery module 1000′ of FIG. 7.

[0075] This embodiment differs from the first embodiment in that the terminal bus bars are not located at the longitudinal ends of the battery cell assembly 100, but are connected to the electrode leads 11, 12 of battery cells that face each other in the longitudinal direction of the longitudinal unit cell 110.

[0076] Also, unlike the first embodiment, the structure of the battery cell assembly 100 is a 2P4S structure in which four rows of longitudinal unit cells 110 are stacked. However, the second embodiment may also apply a 1P4S battery cell assembly similar to that of the first embodiment, except that the position of the terminal bus bar is different. Similarly, a battery cell assembly having a 2P4S structure may be applied to the first embodiment. In addition, as described above, various different structures of battery cell assemblies extending in the longitudinal and thickness directions of the battery cells may be applied to the first and second embodiments.

[0077] The battery module 1000' of the present embodiment includes terminal bus bars 210, 210' coupled to the battery cells included in the battery cell assembly 100. In the present embodiment, the terminal bus bars 210, 210' are coupled to the electrode leads 11, 12 of the battery cells that face each other in the longitudinal direction of the longitudinal unit cell 110 in the battery cell assembly.

[0078] For convenience of illustration, FIG. 8 does not show the vent plate 300 and only shows the electrical connection structure of the battery cell assembly 100.

[0079] In FIG. 8, in the four rows of longitudinal unit cells 110, the electrode leads 11, 12 of battery cells facing each other in the longitudinal direction in the top two rows are not coupled to each other, but are coupled to terminal bus bars 210, 210' of different polarities (see FIG. 10). However, the electrode leads 11, 11, 12, 12 of battery cells adjacent in the thickness direction of the battery cells in the top two rows may be coupled to each other, and the coupled electrode leads may be coupled to the terminal bus bars 210, 210' together. Meanwhile, in the bottom two rows of longitudinal unit cells 110 that are not coupled to the terminal bus bars 210, 210', the electrode leads 11, 12 of battery cells facing each other in the longitudinal direction are coupled to each other. Specifically, in the bottom two rows of longitudinal unit cells 110, the electrode leads 11, 11, 12, 12 of battery cells adjacent in the thickness direction of the battery cells are coupled to each other, and then the electrode leads 12, 12, 11, 11 of other battery cells facing each other in the longitudinal direction in the bottom two rows may be coupled to each other.

[0080] Meanwhile, the electrode leads 11, 12 of the battery cells included in the longitudinal unit cells 110 in the adjacent rows at the longitudinal front and rear ends are bent in the thickness direction of the battery cells and welded to each other.

[0081] The battery module 1000' of this embodiment also includes a venting plate 300 disposed between the rows of the longitudinal unit cells 110 and having a gas venting channel 311 formed therein.

[0082] Referring to FIG. 7, the same number of rows (two rows) of unit cells 110 in the longitudinal direction are arranged on both sides of the ventilation plate 300 .

[0083] 9 illustrates an embodiment of the venting plate 300. The structure of the venting plate 300 of this embodiment is almost the same as that of the venting plate 300 of the first embodiment. That is, a gas venting channel 311 consisting of a longitudinal channel 311a and a width direction channel 311b is formed inside the venting plate 300.

[0084] Also, in the same manner, a venting through hole 312 communicating with a gas venting channel 311 (longitudinal channel) is formed at a position corresponding to a gas pocket of the battery cell, and an electrode lead coupling through hole 313 is formed in front of the venting through hole 312. In addition to a main body 310 extending in the longitudinal direction of the battery cell, a heat propagation prevention plate 320 is also provided which is installed perpendicular to the main body. In the first embodiment, the terminal bus bar is installed at the end of the longitudinal unit cell 110, and is not installed between the battery cells facing each other in the longitudinal direction of the longitudinal unit cell 110. Therefore, both the left and right sides of the heat propagation prevention plate 320 are provided with lead coupling through holes 321 to which the electrode leads of the battery cells facing each other in the longitudinal direction can be coupled (see FIG. 4). However, in this embodiment, terminal bus bars 210, 210' are installed on one side of the ventilation plate 300, and the electrode leads 11, 12 of the battery cells facing each other in the longitudinal direction are respectively coupled to the terminal bus bars 210, 210', but the electrode leads 11, 12 of the battery cells facing each other in the longitudinal direction are not coupled to each other. Therefore, no lead coupling through hole 321 is formed on one side of the heat propagation prevention plate 320, and only one lead coupling through hole 321 is formed on the other side. The electrode leads 11, 12 of the battery cells facing each other in the longitudinal direction located on the other side of the ventilation plate 300 can be coupled to each other through the lead coupling through hole 321.

[0085] 7, this embodiment also includes a module case 400 in which the battery cell assembly 100 and the venting plate 300 are housed. The module case 400 of the present invention includes a front end plate 430' and a rear end plate 440'. The front end plate 430' and the rear end plate 440' are respectively coupled to the combined body of the C-shaped wall 410 and the I-shaped wall 420 to close the front and rear of the module. No terminal bus bar is coupled to the front end plate 430' or the rear end plate 440' of this embodiment.

[0086] The module case 400 includes a venting hole 411 at a position communicating with the gas venting channel 311 of the venting plate 300. For example, in the venting plate 300 of Fig. 9, the venting hole 411 may be formed on an upper surface or a lower surface of the module case 400 at a position connected to an outlet O of a width direction channel 311b which is a part of the gas venting channel 311. The battery module 1000' of the present embodiment may also quickly exhaust gas and flames within the battery module through the gas venting channel 311 and the venting hole 411 of the module case 400, thereby further improving the safety of the expandable battery module.

[0087] FIG. 10 is a perspective view showing a specific connection relationship between battery cells facing each other in the longitudinal direction of the longitudinal unit cell 110 in the embodiment of FIG. 7, and FIG. 11 is a perspective view showing a specific connection relationship between battery cells located at the ends of the longitudinal unit cell 110 in the embodiment of FIG. 7.

[0088] 10 and 11 are perspective views specifically illustrating the electrical connection structure of the battery cell assembly 100 associated with the venting plate 300 when the module case 400 is not assembled.

[0089] 10(a) illustrates the connection between electrode leads of battery cells 10 facing each other in the longitudinal direction corresponding to the middle of a longitudinal unit cell 110. The terminal bus bars 210, 210' are connected to a main body 310 of the venting plate 300 located on the left and right sides of a heat propagation prevention plate 320 on one side (front side) of the venting plate 300, and electrode leads 11, 12 of the battery cells in the front two rows are respectively connected to the terminal bus bars 210, 210'. To facilitate connection of the terminal bus bars 210, 210' to the venting plate 300, terminal bus bar support blocks 220, 220' may be installed on the venting plate, and the terminal bus bars may be fitted and connected to the support blocks 220, 220' (see FIG. 10(a)).

[0090] However, in the front two rows of battery cells, the electrode leads 11, 12 of battery cells facing each other in the longitudinal direction are not coupled to each other.

[0091] FIG. 10(b) shows the other side (rear side) of the ventilation plate 300, in which the electrode leads 11 and 12 of the battery cells on both sides facing each other in the longitudinal direction are welded and connected through the lead connection through holes 321 formed in the heat propagation prevention plate 320 of the ventilation plate 300.

[0092] FIG. 11 illustrates the electrode lead connection relationship of a battery cell located at the end of a longitudinal unit cell 110, where FIG. 11(a) shows the state before connection and FIG. 11(b) shows the state after connection.

[0093] In (a) of FIG. 11, the electrode leads 12, 12 of the two rows of longitudinal unit cells 110 on one side (front side) of the bending plate 300 are bent toward the bending plate 300 in the thickness direction of the battery cells, and the electrode leads 11, 11 of the battery cells of the two rows of longitudinal unit cells 110 on the other side (rear side) are also bent toward the bending plate 300.

[0094] FIG. 11( b ) shows that the electrode leads 11 , 12 of the bent battery cells are welded to each other via the lead connection through-holes 313 formed in the bending plate 300 .

[0095] Figure 12 is a perspective view showing the appearance of the assembled battery module of Figure 7. It shows a state in which the battery cell assembly 100 and the venting plate 300 are housed and assembled in a module case 400, and shows that simple end plates (front end plate 430', rear end plate 440') without terminal bus bars attached are coupled to the front and rear ends of the module case 400. As shown, a venting hole 411 is formed at a predetermined position on the upper surface of the module case 400, which is connected to the gas venting channel of the venting plate 300 in the module.

[0096] FIG. 13 is a schematic diagram of a battery pack 2000 including a battery module stack 1100 constructed from battery modules 1000, 1000' of the present invention.

[0097] As described above, the battery module 1000, 1000' of the present invention includes a battery cell assembly 100 in which a predetermined number of battery cells 10 are stacked in the thickness direction of the battery cells as longitudinal unit cells 110, and a module case 400 corresponding to the battery cell assembly 100 is extended in the longitudinal direction. Therefore, the battery modules 1000, 1000' can be easily connected in the longitudinal direction or thickness direction like Lego blocks. As shown in FIG. 13, a battery module stack 1100 can be formed by stacking a plurality of expandable battery modules 1000, 1000' in the longitudinal direction and / or thickness direction of the battery cells 10 in one battery pack case 2100. In addition to the configuration shown in FIG. 13, the stacking direction (shape) of the expandable battery modules 1000, 1000' can be changed to match the shape of the applied battery pack case 2100. From this perspective, the expandable battery modules 1000, 1000' of the present invention can be said to have a very high degree of design freedom. In particular, as described above, the battery modules 1000, 1000′ of the present invention have a predetermined venting hole 411 on the upper or lower surface of the module case 400. Therefore, for example, when a venting passage communicating with the venting path is formed in the battery pack case 2100, gas inside the battery pack 2000 can also be easily removed.

[0098] The drawings disclosed in the present invention are for the purpose of explanation and not for the purpose of limiting the technical idea of ​​the present invention, and the scope of the technical idea of ​​the present invention is not limited by such drawings. The scope of protection of the present invention should be interpreted by the claims, and all technical ideas within the equivalent range should be interpreted as being included in the scope of the present invention.

[0099] In this specification, terms indicating directions such as up, down, left, right, front, and back are used for the convenience of explanation, but it is self-evident that these terms may change depending on the position of the target object, the position of the observer, etc.

Claims

1. A battery cell assembly comprising two or more battery cells arranged in a row in the longitudinal direction to form a longitudinal unit cell, and the longitudinal unit cells stacked in two or more rows in the thickness direction of the battery cell; a terminal bus bar coupled to a battery cell included in the battery cell assembly; a venting plate disposed between the rows of the longitudinal unit cells and having a gas venting channel formed therein; a module case in which the battery cell assembly and the venting plate are housed; Including, Among the battery cells of the battery cell assembly, adjacent battery cells except for the battery cell coupled to the terminal bus bar have electrode leads directly connected to each other, The battery module further comprises a vent hole formed in the module case, the vent hole communicating with the gas vent channel.

2. The battery module according to claim 1 , wherein the terminal bus bar is coupled to an electrode lead of a battery cell located at a front end or a rear end in a longitudinal direction of the battery cell assembly.

3. electrode leads of battery cells facing each other in a longitudinal direction of the longitudinal unit cell are welded and connected to each other; 3. The battery module of claim 2, wherein electrode leads of battery cells included in a longitudinal unit cell of an adjacent row at a longitudinal front end or a longitudinal rear end of the battery cell assembly to which the terminal bus bar is not coupled are bent in a thickness direction of the battery cell and welded to each other.

4. the module case includes a front end plate and a rear end plate that cover front and rear ends of the battery cell assembly, The battery module according to claim 2 , wherein the terminal bus bar is coupled to the front end plate or the rear end plate.

5. the same number of rows of unit cells in the longitudinal direction are disposed on both sides of the bending plate based on a longitudinal direction of the battery cell; The battery module according to claim 2 , wherein the vent plate is installed to extend in a longitudinal direction of the battery cells across a front end and a rear end of the module case.

6. The gas venting channel is a longitudinal channel extending in a longitudinal direction of the venting plate; a width direction channel communicating with the longitudinal direction channel and opening to the outside of the ventilation plate; Including, The battery module of claim 5 , wherein the width-direction channel is formed at a position corresponding to a midpoint between electrode leads at both ends of a battery cell included in the length-direction unit cell.

7. 7. The battery module of claim 6, wherein the venting plate has a venting through-hole communicating with the longitudinal channel at a position corresponding to a gas pocket connected to an electrode lead of a battery cell included in the longitudinal unit cell.

8. 6. The battery module of claim 5, wherein the venting plate includes a heat propagation prevention plate installed perpendicular to the body portion at a position corresponding to between a body portion extending in a longitudinal direction of the battery cells and an electrode lead of a battery cell facing the longitudinal direction of the longitudinal unit cell.

9. The battery module according to claim 8 , wherein a lead coupling through hole through which an electrode lead of the battery cell passes and is supported is formed in a front end and a rear end of the main body of the venting plate and in the heat propagation prevention plate.

10. The battery module according to claim 1 , wherein the terminal bus bar is coupled to an electrode lead of a battery cell that faces the longitudinal unit cell in the longitudinal direction.

11. The battery cells facing each other in the longitudinal direction of the longitudinal unit cells of the row not connected to the terminal bus bar are connected by welding electrode leads to each other, The battery module according to claim 5 , wherein the electrode leads of the battery cells included in the longitudinal unit cells of adjacent rows at the longitudinal front and rear ends are bent in a thickness direction of the battery cells and welded to each other.

12. the same number of rows of unit cells in the longitudinal direction are disposed on both sides of the bending plate based on a longitudinal direction of the battery cell; The battery module according to claim 10 , wherein the venting plate is installed to extend in a longitudinal direction of the battery cells across a front end and a rear end of the module case.

13. The gas venting channel is a longitudinal channel extending in a longitudinal direction of the venting plate; a width direction channel communicating with the longitudinal direction channel and opening to the outside of the ventilation plate; Including, The battery module of claim 12 , wherein the width-direction channel is formed at a position corresponding to a midpoint between electrode leads at both ends of a battery cell included in the length-direction unit cell.

14. 14. The battery module of claim 13, wherein the venting plate has a venting through-hole communicating with the longitudinal channel at a position corresponding to a gas pocket connected to an electrode lead of a battery cell included in the longitudinal unit cell.

15. 13. The battery module of claim 12, wherein the venting plate comprises a heat propagation prevention plate installed perpendicular to the body portion at a position corresponding to between a body portion extending in a longitudinal direction of the battery cells and an electrode lead of a battery cell facing the longitudinal direction of the longitudinal unit cell.

16. The battery module according to claim 15 , wherein a lead coupling through hole through which an electrode lead of the battery cell passes and is supported is formed in a front end and a rear end of the main body of the venting plate and in the heat propagation prevention plate.

17. A battery pack comprising a battery module stack formed by stacking a plurality of the battery modules according to any one of claims 1 to 16 in at least one of a longitudinal direction and a thickness direction of the battery cells.

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