Battery module with improved fire prevention performance

Abstract

The present invention discloses a battery module capable of effectively preventing the occurrence or spread of fire. The battery module according to one aspect of the present invention includes a cell assembly having a plurality of secondary batteries stacked on one another, and a module case having a lower plate, a side plate, and an upper plate to form an internal space for accommodating the cell assembly, the module case including trap portions recessed outward from at least a portion of the inner surface of the side plate.

Description

[Technical field]

[0001] The present invention relates to a battery, and more particularly to a battery module capable of effectively preventing the occurrence or spread of a fire, a battery pack including the same, and an energy storage system.

[0002] This application claims priority to Korean Patent Application No. 10-2021-0029058, filed on March 4, 2021, the entire contents of which are incorporated herein by reference in their entirety in the specification and drawings. [Background technology]

[0003] Recently, as the demand for portable electronic products such as notebook PCs, video cameras, and mobile phones has increased dramatically and robots and electric vehicles have been commercialized, research into high-performance batteries that can be repeatedly charged and discharged is actively underway.

[0004] Currently, commercial secondary batteries include nickel-cadmium batteries, nickel-metal hydride batteries, nickel-zinc batteries, lithium secondary batteries, etc. In particular, lithium secondary batteries have been attracting attention due to their advantages over nickel-based secondary batteries, such as almost no memory effect, freedom in charging and discharging, a very low self-discharge rate, and high energy density.

[0005] Although a secondary battery may be used alone, it is often configured with a plurality of secondary batteries electrically connected to each other in series and / or parallel. In particular, a plurality of secondary batteries may be electrically connected to each other and housed inside a module case to form a battery module. The battery module may be used alone, or two or more may be electrically connected to each other in series and / or parallel to form a higher level device such as a battery pack.

[0006] Recently, as issues such as power shortages and environmentally friendly energy have been attracting attention, energy storage systems (ESS) for storing generated electricity have been drawing more attention. Typically, the use of such energy storage systems makes it easy to build systems such as smart grid systems, and makes it easy to adjust the supply and demand of electricity in specific regions or cities.

[0007] A battery pack used in an energy storage system may require a much larger capacity than a small or medium-sized battery pack. Therefore, the battery pack may usually include multiple battery modules. In order to increase the energy density, the multiple battery modules are often configured in a dense form in a very small space.

[0008] However, when multiple battery modules are packed together in a small space, they are vulnerable to fire. For example, a thermal propagation situation may occur in one of the battery modules, causing high-temperature gas to be discharged from at least one battery cell. Furthermore, when such gas is discharged, high-temperature sparks may be emitted, and the sparks may contain active material detached from the electrodes inside the battery cells or molten aluminum particles. Furthermore, in some cases, flares may occur in some battery cells. If such sparks or flares escape to the outside of the battery module, it may cause a fire in the battery pack.

[0009] In particular, since a large amount of oxygen may be present outside the battery module, if a spark or the like is discharged outside the battery module, it is highly likely that a fire will be ignited by contacting the oxygen. If a fire occurs in a particular battery module, it may spread to other battery modules or other battery packs in the vicinity. In particular, since many batteries are densely packed in a small space in an energy storage system, it is not easy to extinguish a fire if one occurs. Furthermore, considering the size and role of the energy storage system, a fire inside a battery pack may cause very serious damage to property and life. Therefore, even if a thermal runaway situation occurs in a particular battery cell or module and sparks or flares are generated, it is important to extinguish the fire early to prevent it from leading to a fire in the battery module or battery pack. Summary of the Invention [Problem to be solved by the invention]

[0010] The present invention has been made in consideration of the above problems, and aims to provide a battery module configured to effectively suppress fires even if sparks or flares are generated internally due to thermal runaway, a battery pack including the same, and an energy storage system.

[0011] However, the technical problems that the present invention aims to solve are not limited to the problems described above, and other problems not mentioned will be clearly understood by those skilled in the art from the description of the invention below. [Means for solving the problem]

[0012] In order to achieve the above object, a battery module according to one aspect of the present invention includes a cell assembly having a plurality of secondary batteries stacked on each other, and a module case having a lower plate, a side plate and an upper plate to form an internal space to accommodate the cell assembly, and a trap portion formed by recessing outward on at least a portion of an inner surface of the side plate.

[0013] Here, the cell assembly may be configured such that a plurality of pouch-type secondary batteries are vertically stacked in a horizontal state.

[0014] In addition, the cell assembly may be configured such that electrode leads of the pouch-type secondary batteries are positioned in a front-rear direction of the module case, and at least one of the front and rear of the module case is open.

[0015] The battery module according to the present invention may further include a bus bar assembly positioned in the opening of the module case and configured to be coupled to the electrode lead.

[0016] In addition, the module case may be configured such that, when gas is generated in the cell assemblies, the generated gas is discharged to at least one of the front and rear.

[0017] The trap portion may be formed at least in a central portion in the front-rear direction of the side plate.

[0018] Also, the trap portion may be formed such that at least a portion of the trap portion is recessed to have a greater depth as it extends forward or backward.

[0019] The module case may further include a protrusion formed on at least one end of the trap portion so as to protrude toward a center.

[0020] Also, the trap portion may have at least one end recessed in the front-rear direction.

[0021] In order to achieve the above object, a battery pack according to another aspect of the present invention includes a battery module according to the present invention.

[0022] In order to achieve the above object, according to another aspect of the present invention, an energy storage system includes a battery module according to the present invention. Effect of the Invention

[0023] According to the present invention, the occurrence of a fire in a battery module can be effectively prevented.

[0024] In particular, according to one aspect of the present invention, even if a spark or flare occurs due to a thermal runaway phenomenon in a specific battery cell included in a battery module, the discharge of the spark or the like to the outside can be effectively blocked.

[0025] Therefore, according to one aspect of the present invention, it is possible to suppress the occurrence of fires due to external emissions of sparks, etc.

[0026] Furthermore, according to one embodiment of the present invention, gas can be easily discharged to the outside of the battery module while preventing the leakage of sparks, etc. This prevents the battery module from exploding while fundamentally preventing the occurrence of a fire outside the battery module.

[0027] Furthermore, according to one aspect of the present invention, even if a fire occurs inside the battery module, the fire does not spread and can be quickly extinguished by preventing the flames from escaping.

[0028] In addition, the present invention provides various other effects, which will be described in each embodiment, and descriptions of effects that can be easily inferred by those skilled in the art will be omitted.

[0029] The following drawings attached to this specification illustrate preferred embodiments of the present invention and, together with the detailed description of the invention, serve to further understand the technical ideas of the present invention. Therefore, the present invention should not be interpreted as being limited to only the matters described in the drawings. [Brief description of the drawings]

[0030] [Figure 1] 1 is a perspective view illustrating a schematic configuration of a battery module according to an embodiment of the present invention; [Diagram 2] FIG. 2 is an exploded perspective view of a portion of the configuration of FIG. [Diagram 3] 1 is a top view of a configuration of a battery module according to an embodiment of the present invention; [Figure 4] 10 is a diagram illustrating a spark trapping effect when a spark occurs in a secondary battery in a battery module according to an embodiment of the present invention. FIG. [Diagram 5] 1 is a perspective view showing a cell assembly separated in a battery module according to an embodiment of the present invention; [Figure 6] FIG. 4 is a top view illustrating a schematic configuration of a battery module according to another embodiment of the present invention. [Figure 7] 13 is a top view illustrating a schematic configuration of a battery module according to still another embodiment of the present invention. FIG. [Figure 8] FIG. 8 is an enlarged view of a portion E1 in FIG. [Figure 9] 13 is a top view illustrating a schematic configuration of a battery module according to still another embodiment of the present invention. FIG. [Figure 10] 13 is a top view illustrating a schematic configuration of a battery module according to still another embodiment of the present invention. FIG. [Figure 11] 13 is a top view illustrating a schematic configuration of a battery module according to still another embodiment of the present invention. FIG. [Figure 12] 13 is a top view illustrating a schematic configuration of a battery module according to still another embodiment of the present invention. FIG. [Figure 13] 13 is a top view illustrating a schematic configuration of a battery module according to still another embodiment of the present invention. FIG. [Figure 14] 13 is a top view illustrating a schematic configuration of a battery module according to still another embodiment of the present invention. FIG. [Figure 15] 13 is a top view illustrating a schematic configuration of a battery module according to still another embodiment of the present invention. FIG. [Figure 16] FIG. 16 is an enlarged view of a portion A6 in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0031] Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the attached drawings. Prior to this, the terms and words used in the specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings, but should be interpreted as having meanings and concepts corresponding to the technical ideas of the present invention, in accordance with the principle that the inventor himself can appropriately define the concepts of terms in order to best describe the invention.

[0032] Therefore, it should be understood that the embodiments described in this specification and the configurations shown in the drawings are merely the most preferred embodiment of the present invention and do not represent the entire technical idea of ​​the present invention, and that there may be various equivalents and modifications that can be substituted for them at the time of this application.

[0033] FIG. 1 is a perspective view showing a schematic configuration of a battery module according to an embodiment of the present invention, and FIG. 2 is an exploded perspective view of a portion of the configuration of FIG.

[0034] 1 and 2, a battery module according to the present invention includes a cell assembly 100 and a module case 200.

[0035] The cell assembly 100 may include a plurality of secondary batteries 110 (battery cells). The secondary batteries 110 may include an electrode assembly, an electrolyte, and a battery case. In particular, as shown in FIGS. 1 and 2, the secondary batteries 110 included in the cell assembly 100 may be pouch-type secondary batteries 110. However, other types of secondary batteries 110, such as cylindrical batteries and prismatic batteries, may also be adopted in the cell assembly 100 of the present invention.

[0036] A plurality of secondary batteries 110 may be stacked on one another to form a cell assembly 100. For example, as shown in the drawings, a plurality of secondary batteries 110 may be stacked in a vertical direction (Z-axis direction in the drawings). Each pouch-type secondary battery 110 includes an electrode lead 111, which may be located at both ends or one end of each secondary battery 110. A secondary battery 110 having electrode leads 111 protruding from both sides is called a bidirectional cell, and a secondary battery having electrode leads 111 protruding from one side is called a unidirectional cell. As an example, the secondary battery 110 shown in the embodiment of FIGS. 1 and 2 is a bidirectional cell, and the electrode leads 111 are located at both ends in the Y-axis direction. However, the secondary battery 110 of the battery module according to the present invention may have a configuration in which the electrode lead 111 is located only at one end in the Y-axis direction, for example, at the end in the +Y-axis direction. The present invention is not limited by the specific type or shape of the secondary battery 110, and various secondary batteries 110 known at the time of filing of the present invention may be used in the cell assembly 100 of the present invention. In this specification, the secondary battery 110 will be described mainly as a bidirectional cell.

[0037] The module case 200 may have a space formed therein and may be configured to accommodate the cell assembly 100. As shown in the drawings, the module case 200 may further include a lower plate 210, a side plate 220, and an upper plate 230. The module case 200 may be configured such that at least some of the plates are integrally manufactured or are connected to each other by a fastening method such as bolts or welding. For example, the lower plate 210 and the side plate 220 may be integrally manufactured to form a lower case.

[0038] The lower plate 210, the side plate 220, and the upper plate 230 may define an internal space and accommodate the cell assembly 100 in the internal space. For example, the lower plate 210 and the side plate 220 may be formed in a U-shape or a box shape to form a lower case. The upper plate 230 may be configured to be coupled to an upper open end of the lower case and cover an upper end of the cell assembly 100. The upper plate 230 may be configured in a shape in which both left and right ends are bent as shown in the drawings, but may be formed in various other shapes and configured to be coupled to the side plate 220. Alternatively, the module case 200 may be formed in the form of a mono-frame in which the lower plate 210, the side plate 220, and the upper plate 230 are integrated.

[0039] Particularly, in the present invention, the module case 200 may include a trap portion 221. The trap portion 221 may be formed on the side plate 220, particularly on the inner surface of the side plate 220. The trap portion 221 may be formed such that at least a portion of the inner surface of the side plate 220 is recessed outward. This will be further described with reference to FIG. 3.

[0040] 3 is a top view of a battery module according to an embodiment of the present invention, in which an upper plate 230 is removed from the battery module of FIGS.

[0041] 1 to 3, the side plate 220 of the module case 200 may include a left plate 220L and a right plate 220R. Here, the left plate 220L and the right plate 220R may be located at both ends in the X-axis direction with the cell assembly 100 at the center in the drawings. In particular, the side plate 220 may include a trap portion 221 formed by recessing an inner surface toward the outside as shown by a circle in FIG. 3. Here, the outside direction may mean a direction opposite to the direction in which the battery cells are located, that is, the outside direction of the battery module. For example, in the configuration of FIG. 3, the left plate 220L may include a trap portion 221 formed by recessing a part of an inner surface toward the left side (+X-axis direction) as shown by an arrow. And the right plate 220R may include a trap portion 221 formed by recessing a part of an inner surface toward the right side (-X-axis direction) as shown by an arrow. In this specification, unless otherwise specified, the direction toward the center of the battery module, for example, the direction in which the cell assembly 100 is located, is referred to as the inner direction, and the direction toward the outside of the battery module is referred to as the outer direction.

[0042] The trap portion 221 can be said to be formed recessed when the inner surface of the side plate 220 is used as a reference, and the outer surface can be formed to be bulged in order to form the recessed portion. That is, as shown in Figures 1 to 3, the side plate 220 can be formed so that the inner surface is recessed and the outer surface is protruding in order to form the trap portion 221. However, when the side plate 220 is formed to be thick, the outer surface can be formed so that it does not protrude outward.

[0043] According to this configuration of the present invention, the trap portion 221 formed in the module case 200 can effectively prevent high-temperature sparks, flares, and the like from escaping to the outside of the module case 200. This will be described in more detail with reference to FIG.

[0044] FIG. 4 is a diagram illustrating a spark trapping effect when a spark occurs in one of the secondary batteries 110 in a battery module according to an embodiment of the present invention.

[0045] 4, when a spark is emitted from a particular secondary battery 110 as indicated by K, the emitted spark may be trapped by the trap portion 221 of the side plate 220. That is, the spark emitted from the secondary battery 110 may be discharged into the internal space of the module case 200, flow into the recessed portion of the trap portion 221 present in the internal space of the module case 200, and move along the recessed shape, and the movement may be blocked at the end of the recessed portion.

[0046] For example, within the trapping portion 221, the sparks may move as indicated by the arrows in FIG. 4, and the movement may be blocked or the movement direction may be changed at the horizontal ends of the trapping portion 221 as indicated by A1 and A1'. As a result, the trapping portion 221 may confine sparks generated within the module case 200 in an internal recessed space. Therefore, the sparks are not discharged to the outside of the module case 200. According to this implementation effect, the sparks are prevented from coming into contact with oxygen present outside the module case 200, thereby reducing the risk of fire. In addition, in this case, it is possible to prevent the sparks from moving to other components, for example, other battery modules, outside the battery module, and thus preventing the battery module from starting a fire.

[0047] The cell assembly 100 may be configured such that a plurality of pouch-type secondary batteries 110 are vertically stacked in a horizontal state, which will be described in more detail with reference to FIG.

[0048] FIG. 5 is a perspective view showing a cell assembly 100 separated from a battery module according to an embodiment of the present invention.

[0049] Referring to FIG. 5, in the battery module according to the present invention, the secondary battery 110 included in the cell assembly 100 is a pouch-type secondary battery 110, which may be arranged in a lying state. In particular, the pouch-type secondary battery 110 may be arranged in a lying state with two broad surfaces formed approximately facing upward and downward. For example, the XY plane in FIG. 5 may be the same plane as the lower plate 210 of the module case 200, and one surface of the secondary battery 110 stacked at the bottom may be placed on the XY plane. The secondary batteries 110 in this lying state may be stacked and arranged in a vertical direction (Z-axis direction in the drawing) with the upper and lower surfaces facing each other.

[0050] According to such a configuration of the present invention, the sealing portions of all the secondary batteries 110 can be configured to face the trap portion 221 of the side plate 220. As a result, even if a spark or the like is discharged from any of the secondary batteries 110, the discharged spark can be trapped by the trap portion 221. For example, in the configuration of FIG. 5, even if a spark is generated in any of the secondary batteries 110 stacked vertically and is discharged in the direction of the arrows A2 and A2', the discharged spark can be directed toward the trap portion 221 of the side plate 220. As a result, the trap portion 221 can respond to the discharge of a spark for all the stacked secondary batteries 110.

[0051] In particular, the cell assembly 100 may be configured such that the electrode leads 111 of the pouch-type secondary batteries 110 are located in the front-rear direction of the module case 200. For example, referring to Fig. 5, each pouch-type secondary battery 110 included in the cell assembly 100 may be configured such that the electrode leads 111 face forward (+Y axis direction) or backward (-Y axis direction).

[0052] Also, the module case 200 may be configured so that at least one of the front and rear is open. For example, referring to the configuration of Fig. 5, the module case 200 may include a front plate 240 and a rear plate 250. In this case, the front plate 240 may be configured so that a portion thereof is open, such as a portion indicated by O1. Also, the rear plate 250 may be configured so that a portion thereof is open, such as a portion indicated by O2.

[0053] According to the above-described configuration of the present invention, when sparks are ejected from the cell assembly 100 together with gas, the gas can be smoothly discharged to the outside of the module case 200 while preventing the sparks from being discharged to the outside of the module case 200. For example, referring to the configuration shown in FIG. 5, when gas and sparks are discharged in the directions A2 and A2', the gas can be discharged to the front opening O1 or the rear opening O2 as a gas, regardless of the flow caused by the trap unit 221. As a result, even if gas is generated from the cell assembly 100, the internal pressure of the module case 200 can be prevented from increasing above a certain level, and the explosion of the battery module can be prevented. Meanwhile, sparks may include particles or substances such as solid, liquid, gel, or sol, and the movement of sparks in such a state can be restricted by the trap unit 221 as described in FIG. 4. Therefore, according to the configuration of the present invention, it is possible to achieve the effect of preventing both the explosion of the battery module and the outflow of sparks.

[0054] In particular, according to the embodiment, the trap portion 221 for preventing sparks in the module case 200 is provided on the side plate 220, and the openings O1 and O2 for discharging gas may be located at the front and / or rear of the module case 200. Here, the trap portion 221 may be located facing a side of the sealing portion of the secondary battery 110 where the electrode lead 111 is not located. And the openings O1 and O2 may be located facing a side of the sealing portion of the secondary battery 110 where the electrode lead 111 is located. In the pouch-type secondary battery 110, when the internal pressure increases due to thermal runaway or the like, it is highly likely that the portion from which the gas is discharged due to explosion is mainly a portion where the electrode lead 111 is not located. That is, in the configuration of FIG. 4, when the secondary battery 110 explodes, the explosion portion is highly likely to be the sealing portion at both ends in the ±X-axis direction (both ends on the left and right sides), and explosion is unlikely to occur at the sealing portion at both ends in the ±Y-axis direction (both ends on the front and back sides).

[0055] More specifically, the pouch-type secondary battery 110 may be formed in a substantially rectangular shape when viewed from above in a lying state. In this case, the pouch-type secondary battery 110 is configured such that the periphery of the storage portion is surrounded by four sealing portions, and the left and right sealing portions (wing portions) where the electrode leads 111 are not located are often formed longer than the front and rear sealing portions (terrace portions) where the electrode leads 111 are located.

[0056] Therefore, gas and sparks due to the explosion are likely to be ejected in the directions of arrows A2 and A2' in FIG. 5, i.e., from the left and right sealing portions (wing portions). However, according to the above embodiment, the trap portion 221 may be present at the ejection site of the gas and sparks. In particular, the sparks must pass through the trap portion 221 before moving toward the openings O1 and O2. This allows the movement of the sparks to be restricted by the trap portion 221, as shown in FIG. 4. Therefore, according to the above embodiment, the spark exhaust effect of the trap portion 221 can be further improved.

[0057] Meanwhile, in the above-described embodiment such as Fig. 5, the left and right sealing portions of each pouch-type secondary battery 110 of the cell assembly 100 are folded upward. This configuration can reduce the volume of the cell assembly 100. However, this is merely an example, and the present invention is not necessarily limited to this configuration.

[0058] Furthermore, the battery module according to the present invention may further include a bus bar assembly 300 as shown in FIGS.

[0059] The bus bar assembly 300 may be positioned in the openings O1 and O2 of the module case 200. In particular, the electrode leads 111 of the cell assemblies 100 may be positioned in the openings O1 and O2 of the module case 200. Thus, the bus bar assembly 300 may be configured to be coupled with the electrode leads 111 of the cell assemblies 100.

[0060] For example, referring to the configuration of FIG. 2, the cell assembly 100 may be configured such that the electrode leads 111 are located at both ends in the Y-axis direction, and the module case 200 may be configured to have both ends in the Y-axis direction open (O1, O2). The bus bar assembly 300 may be coupled to such open portions O1, O2. If the electrode leads 111 of the cell assembly 100 are positioned to protrude only in one side of the battery module, for example, in the +Y-axis direction, the module case 200 may be configured to be open only in the +Y-axis direction. The module case 200 may be configured to be sealed except for the open portion to which the bus bar assembly 300 is coupled. Therefore, if gas is generated inside the module case 200, the generated gas may be discharged only to the side where the bus bar assembly 300 is located.

[0061] As described above, the bus bar assembly 300 may be configured to be located at least on one side of the module case 200, for example, at both front and rear ends (both ends in the Y-axis direction in FIG. 2) of the module case 200. The bus bar assembly 300 may include a module bus bar 310 and a bus bar housing 320.

[0062] Here, the module bus bar 310 may be made of an electrically conductive material, for example, a metal material such as copper or nickel. The module bus bar 310 may be configured to be electrically connected to the electrode leads 111 of the cell assembly 100. In particular, the module bus bar 310 may be directly in contact with the electrode leads 111 and may be welded or bolted to the electrode leads 111. The module bus bar 310 may electrically connect the electrode leads 111 to each other, or may transmit voltage information sensed from the electrode leads 111 to an external control unit, for example, a Battery Management System (BMS).

[0063] The busbar housing 320 may be configured to mount the module busbar 310. For example, the busbar housing 320 may have a shape corresponding to the surface of the module busbar 310, for example, a planar portion as a mounting portion, so that the module busbar 310 can be mounted. The busbar housing 320 may support the module busbar 310 so that the mounted module busbar 310 stably maintains its position. For example, the busbar housing 320 may be coupled and fixed to the module busbar 310 using various fastening methods such as bolts, rivets, welding, insertion, and adhesion. The busbar housing 320 may be made of an electrically insulating material such as plastic (polymer) so as not to be electrically conductive to the module busbar 310. The busbar housing 320 may be coupled and fixed to the module case 200, particularly the front plate 240 and the rear plate 250. In this case, the coupling method between the busbar housing 320 and the module case 200 may be embodied in various forms such as bolts, rivets, welding, insertion, and adhesion.

[0064] The bus bar housing 320 may have slots 321 formed therein so that the electrode leads 111 can pass through. Typically, for the stability of the connection, the module bus bar 310 is attached to the outer surface of the bus bar housing 320, and the electrode leads 111 may pass through the slots 321 from the inside of the bus bar housing 320 and then contact the outer surface of the module bus bar 310 located on the outside.

[0065] The slot 321 may be formed in a shape corresponding to the shape of the electrode lead 111 so that the electrode lead 111 can be easily inserted therethrough. For example, the slot 321 may be formed to extend long in the left-right direction (X-axis direction in the drawing) as shown in the drawing. Furthermore, a plurality of such slots 321 may be formed in the bus bar housing 320. When the pouch-type secondary batteries 110 are stacked in the vertical direction (Z-axis direction in the drawing), a plurality of electrode leads 111 may be present in the vertical direction. Thus, a plurality of slots 321 may also be arranged at a predetermined distance apart in the vertical direction as shown in FIG. 2.

[0066] The slot 321 may support the electrode lead 111 by passing the electrode lead 111 therethrough, and may also discharge vent gas. The slot 321 may have a gap around the electrode lead 111 when the electrode lead 111 passes through it. The other parts of the module case 200 may be configured to be substantially sealed. In this case, if a thermal runaway condition occurs in at least one of the secondary batteries 110 included in the cell assembly 100 and vent gas is generated, the gas may increase the internal pressure of the battery module. However, since a gap is formed around the electrode lead 111 passing through the slot 321, gas inside the battery module may be discharged to the outside through the slot 321. However, sparks and flares other than gas are prevented from being discharged to the outside by the trap unit 221, as described above.

[0067] As in the above-described embodiment, in the battery module according to the present invention, the module case 200 may be configured such that, when gas is generated in the cell assemblies 100, the generated gas is discharged to at least one of the front and rear. In particular, the portion of the module case 200 from which gas is discharged to the outside may be the slot 321 of the bus bar assembly. In this configuration, the trap portion 221 may be formed in the side plate 220 of the module case 200. That is, the trap portion 221 may be formed in the left plate 220L and the right plate 220R of the module case 200.

[0068] According to this configuration of the present invention, gas and sparks discharged from the cell assembly 100 can pass through the trap unit 221 before flowing out of the module case 200. As a result, gas in a gaseous state can be smoothly discharged to the outside of the module case 200, while sparks in a state other than a gaseous state can be prevented from being discharged to the outside of the module case 200 by the trap unit 221.

[0069] In the battery module according to the present invention, the trap portion 221 may be formed at least in the central portion in the front-rear direction of the side plate 220. This will be described in more detail with reference to FIG.

[0070] FIG. 6 is a top view illustrating a schematic configuration of a battery module according to another embodiment of the present invention.

[0071] 6, the front-rear direction of the side plate 220 can be said to be ±Y axis directions. The center line in the front-rear direction of the side plate 220 can be said to be line A3-A3'. In this case, the trap portion 221 can be configured to be formed at least on line A3-A3'.

[0072] Further, the trap portion 221 may be configured to extend in the front-rear direction around the line A3-A3'. That is, in the configuration of Fig. 6, the trap portion 221 may be configured to extend in the +Y-axis direction and the -Y-axis direction around the center line A3-A3' in the front-rear direction. In this case, the trap portion 221 may be positioned to face the central portion of the side sealing portion, i.e., the wing portion, of each of the plurality of pouch-type secondary batteries 110.

[0073] In the case where an explosion occurs due to an increase in internal pressure in the pouch-type secondary battery 110, the explosion is likely to occur at the center of the wing portion, which has a relatively long length in the sealing portion. Therefore, according to the above embodiment, when sparks or flares are ejected from the cell assembly 100, the ejected sparks or flares can immediately flow into the trap portion 221.

[0074] Further, the trap portion 221 may be formed to extend from the center of the side plate 220 in the front-rear direction (Y-axis direction) to a portion where the terrace portion S2 is located.

[0075] 6, the pouch-type secondary battery 110 included in the cell assembly 100 may be divided into a housing portion R in which an electrode assembly is housed and a sealing portion S in which an upper pouch and a lower pouch are welded. In particular, the sealing portion S may be configured to include a wing portion S1 and a terrace portion S2 and to surround the housing portion R.

[0076] In this case, the trap portion 221 may extend in the front-rear direction from the center portion (line A3-A3') of the side plate 220 to a portion where the terrace portion S2 of the pouch-type secondary battery 110 is located or further. That is, the trap portion 221 may be configured to extend at least to a portion where the storage portion R of the pouch-type secondary battery 110 ends, as shown by the portions indicated by lines A4-A4' and A5-A5' in FIG.

[0077] According to this configuration of the present invention, the trap portion 221 may be positioned to face the entire wing portion S1 of the pouch-type secondary battery 110. That is, the trap portion 221 of the side plate 220 may cover the entire wing portion S1 of the pouch-type secondary battery 110 included in the cell assembly 100. As a result, even if a spark or flare erupts from the wing portion S1 of any of the pouch-type secondary batteries 110, the effect of preventing movement by the trap portion 221 can be reliably guaranteed.

[0078] The trap portion 221 may be formed such that the depth of the recessed portion increases as the trap portion 221 advances toward the front or rear of at least a portion of the trap portion 221. This will be described in more detail with reference to FIGS.

[0079] Fig. 7 is a top view showing a schematic configuration of a battery module according to another embodiment of the present invention, and Fig. 8 is an enlarged view of a portion E1 in Fig. 7. This embodiment will be described focusing on differences from the previous embodiment, and detailed description of parts that are the same or similar to the previous embodiment will be omitted.

[0080] 7, the trap portion 221 may be configured such that a portion located on the front side (right side in FIG. 7) of the side plate 220 relative to the center line A3-A3' in the front-rear direction is recessed deeper toward the front (+Y axis direction). The trap portion 221 may be configured such that a portion located on the rear side (left side in FIG. 7) of the side plate 220 relative to the center line A3-A3' in the front-rear direction is recessed deeper toward the rear (-Y axis direction).

[0081] In particular, in this configuration, an inclined surface may be formed on the inner surface of the trap portion 221. For example, as shown in the parts D2 and D2' in the drawings, an inclined surface may be formed in a portion located on the front side of the trap portion 221 such that the depth becomes deeper toward the front (+Y axis direction). Also, as shown in the parts D1 and D1' in the drawings, an inclined surface may be formed in a portion located on the rear side of the trap portion 221 such that the depth becomes deeper toward the rear (-Y axis direction).

[0082] According to this configuration of the present invention, the trap portion 221 can further improve the effect of preventing sparks, flares, and the like. In particular, sparks, etc. ejected from the wing portions of the secondary battery 110 can move in the front-rear direction (±Y-axis direction) along the inclined surfaces D1, D1', D2, and D2' of the trap portion 221. Then, when the sparks reach the front-rear end portions of the trap portion 221, they can no longer move any further at the portions indicated by E1, E1', E2, and E2', and the direction of movement can change. At this time, the direction of movement can be bent at an angle greater than 90°.

[0083] More specifically, referring to Fig. 8, the angles of the corners of the front and rear ends E1, E1', E2, and E2' of the trap portion 221 can be said to be acute angles. However, from the viewpoint of the movement direction of the sparks, etc., the angles can be said to be greater than 90°. That is, referring to Fig. 8(a), the sparks, etc. move in the direction of the arrow F1 in the trap portion 221, and when they hit the end of the trap portion 221, their direction is changed and they can move in the direction of the arrow F2. If the center points of the arrows F1 and F2 are aligned, it will be as shown in Fig. 8(b). In this case, the angle θ formed by the arrows F1 and F2 can be said to be an obtuse angle greater than 90°.

[0084] Therefore, according to the above embodiment, since the moving direction of the sparks or the like is changed to an obtuse angle greater than 90°, the trap portion 221 can more reliably suppress the outward movement of the sparks or the like.

[0085] Meanwhile, in FIG. 7, the side plate 220 is shown with an outer surface inclined to correspond to the inclination of the inner surface, but the present invention is not necessarily limited to this form. That is, the inner surface of the side plate 220 may be formed to be inclined, while the outer surface may be configured to be flat. However, when the outer surface is formed to be inclined as shown in FIG. 7, the central portion of the side plate 220 may have a shape recessed inward when viewed from the outside. In this case, when a plurality of battery modules are stacked horizontally, the recessed portion on the outer side of the side plate 220 is a space between the battery modules, and may be utilized as a flow path for circulating cooling air, etc.

[0086] The trap part 221 may be configured to have projections and recesses on its inner surface, which will be described in more detail with reference to FIG.

[0087] 9 is a top view showing a schematic configuration of a battery module according to another embodiment of the present invention, which will be described with reference to FIG.

[0088] 9, the trap portion 221 may be configured to have a plurality of grooves recessed outward on its inner surface, as indicated by G. In particular, the trap portion 221 may be configured to have a plurality of grooves formed in its front and rear portions based on the center line A3-A3' in the front-rear direction of the side plate 220.

[0089] According to such a configuration of the present invention, the movement of sparks and the like can be prevented by the unevenness formed on the inner surface of trap portion 221, i.e., by the multiple grooves G. This further prevents sparks and the like from being discharged to the outside through openings O1 and O2 of module case 200.

[0090] In particular, each groove G may be formed such that the depth of the recessed portion increases in the forward / rearward direction based on the center line A3-A3' in the forward / rearward direction. That is, each of the grooves G formed in the trap portion 221 may have an inclined surface as shown by D3 in Fig. 9, and the inclined surface D3 may be configured to increase in depth in the forward / rearward direction, which is the gas flow direction.

[0091] According to this configuration of the present invention, the movement direction of the sparks or the like can be changed to an angle (obtuse angle) larger than a right angle for each groove, thereby further improving the effect of the trap portion 221 in suppressing the movement of the sparks or the like.

[0092] In the embodiment of Fig. 9, a configuration is shown in which multiple projections and recesses are formed on the inner surface of the trap portion 221 in a state parallel to the front-rear direction (Y-axis direction), but the present invention is not limited to such an embodiment. For example, the multiple grooves G described in Fig. 9 may also be formed on each of the inclined surfaces D1, D1', D2, and D2' as shown in Fig. 7. In this case, the spark prevention effect of the inclined surface of the trap portion 221 itself and the spark prevention effect of the projections and recesses are combined, and the effect can be further increased.

[0093] Also, the module case 200 may further include a protrusion formed to protrude toward the center on at least one end of the trap part 221. This will be described in more detail with reference to FIG.

[0094] 10 is a top view showing a schematic configuration of a battery module according to still another embodiment of the present invention, which will be described with reference to FIG.

[0095] 10, the module case 200 may further include a protrusion 222 at the front end and / or rear end of the trap portion 221. The protrusion 222 may be configured to protrude toward the inside of the trap portion 221 on the side plate 220 of the module case 200. For example, referring to an enlarged portion of the rear end of the trap portion 221 in FIG. 10, the protrusion 222 may be configured to protrude forward (in the +Y-axis direction) and to cover a portion of the rear end of the trap portion 221.

[0096] According to this configuration of the present invention, it is possible to more effectively block the discharge of sparks to the outside by blocking or further redirecting the movement of sparks at the end of the trap portion 221. That is, the sparks that have flowed into the inside of the trap portion 221 can be redirected in the opposite direction at the end of the trap portion 221 as shown by the arrow in the enlarged view of Fig. 10. This allows the sparks to remain further inside the trap portion 221, thereby further improving the trapping effect of the trap portion 221 for sparks.

[0097] Also, at least one end of the trap portion 221 may be recessed in the front-rear direction, which will be described in more detail with reference to FIGS.

[0098] 11 and 12 are top views showing a schematic configuration of a battery module according to still another embodiment of the present invention. This embodiment will also be described focusing on differences from the above-mentioned embodiment.

[0099] 11 and 12, a trap portion 221 is formed on a side plate 220 of a module case 200, and an end portion of the trap portion 221 in a front-rear direction (Y-axis direction) may be recessed in the front-rear direction.

[0100] For example, in Fig. 11, the front end of the trap portion 221 may be recessed toward the front (+Y axis direction) as shown by H1' to provide a groove in the front. Also, in Fig. 11, the rear end of the trap portion 221 may be recessed toward the rear (-Y axis direction) to provide a groove in the rear as shown by H1. In particular, in the configuration of Fig. 11, inclined surfaces may be formed on the front and rear end sides of the trap portion 221 in order to provide grooves (recessed portions) at the front and rear end sides of the trap portion 221.

[0101] In another example, in Fig. 12, the front end of the trap portion 221 may be recessed in the front direction (+Y axis direction) as shown by H2' to provide a groove in the front. Also, in Fig. 12, the rear end of the trap portion 221 may be recessed in the rear direction (-Y axis direction) to provide a groove in the rear as shown by H2. In particular, in the configuration of Fig. 12, in order to provide grooves (recesses) at the front and rear ends of the trap portion 221, the front and rear end sides of the trap portion 221 may be recessed in the front and rear direction.

[0102] According to such a configuration of the present invention, the effect of trap portion 221 in preventing sparks, flares, and the like can be more stably ensured. In particular, when sparks, flares, and the like flow into the internal space of trap portion 221, the sparks and flares move in the front-rear direction, and the recesses located on the front and rear end sides make it difficult for them to flow out of the internal space of trap portion 221. Furthermore, spark particles and the like can be inserted into the grooves provided on the front and rear end sides of the trap portion. This further improves the effect of trap portion 221 in preventing the discharge of sparks, flares, and the like.

[0103] 13 is a top view showing a schematic configuration of a battery module according to still another embodiment of the present invention. This embodiment will also be described focusing on differences from the above-mentioned embodiments.

[0104] Referring to FIG. 13, the battery module according to the present invention may further include a mesh member 400. The mesh member 400 may be configured with a plurality of holes formed therein. For example, the mesh member 400 may be configured in a form in which a plurality of holes are provided in a plate-shaped member. Alternatively, the mesh member 400 may be configured in a form like a net in which different wires cross each other at right angles. In this case, the mesh member 400 is easy to manufacture, and a large number of holes may be formed while reducing the mesh size. The mesh member 400 may be configured to be drawn into the internal space of the trap portion 221. Also, the mesh member 400 may be arranged such that holes are formed in the front-rear direction. The mesh member 400 may be arranged at both ends of the trap portion 221 in the front-rear direction.

[0105] According to this embodiment of the present invention, the movement of sparks, flares, etc. can be further blocked by the mesh member 400. That is, when sparks or flares move in the front-rear direction together with gas in the internal space of the trap unit 221 and reach the mesh member 400, the gas in a gaseous state easily passes through the mesh, but particles contained in the sparks or flares are filtered by the mesh member 400. This improves the effect of preventing sparks, flares, etc. from being discharged to the outside.

[0106] 14 is a top view showing a schematic configuration of a battery module according to still another embodiment of the present invention. This embodiment will also be described focusing on the differences from the above-mentioned embodiment.

[0107] Referring to FIG. 14, the battery module according to the present invention may further include a pore member 500. The pore member 500 may be configured to have a plurality of pores therein. In particular, the inner pores may be configured to communicate with the outside. That is, the pores of the pore member 500 are spaces filled with only gas, and the pores may be configured to be not sealed but to be able to communicate with the outside. For example, the pore member 500 may be configured by intertwining a plurality of wires, particularly a plurality of wires made of a material such as metal or polymer. In particular, the pore member 500 may be configured to be inserted into the inner space of the trap unit 221.

[0108] According to the configuration of the present invention, the pores formed in the porous member 500 can more effectively prevent the sparks or flares that have flowed into the trap portion 221 from moving to the outside. In particular, in the case of active material particles contained in the sparks or flares, they are captured in the pores of the porous member 500, and thus are more reliably prevented from being discharged to the outside of the module case 200.

[0109] Fig. 15 is a top view showing a schematic configuration of a battery module according to still another embodiment of the present invention, and Fig. 16 is an enlarged view of a portion A6 in Fig. 15. This embodiment will also be described focusing on the differences from the above-mentioned embodiments.

[0110] 15, a plurality of blocking protrusions P may be formed on the inner surface of the trap portion 221. The blocking protrusions P are formed to protrude from the inner surface of the side plate 220 in a direction toward the cell assembly 100 (X-axis direction). The blocking protrusions P may have a space therein, and the space may be configured to be open in the front-rear direction, particularly in the direction toward the center line A3-A3' in the front-rear direction of the side plate 220. The internal space of the blocking protrusions P may be configured to be closed toward both front and rear ends of the side plate 220.

[0111] More specifically, referring to the configuration of Fig. 16, the right side of the blocking protrusion P in the drawing can be said to be in the direction toward the center line A3-A3' in the front-rear direction (+Y axis direction). And the left side of the blocking protrusion P can be said to be in the direction toward the rear end (-Y axis direction). In this case, the right side of the blocking protrusion P can be configured to be open and the left side of the blocking protrusion P can be configured to be closed.

[0112] According to this configuration of the present invention, the discharge of sparks, flares, etc. to the outside can be more reliably blocked by the blocking protrusions P formed on the inner surface of the trap portion 221. For example, referring to Fig. 16, as shown by the arrows, sparks, flares, etc. moving forward or backward along the inner surface of the trap portion 221 can be blocked and redirected as they flow into the internal space of the blocking protrusions P. This can further improve the effect of blocking the movement of sparks, flares, etc.

[0113] The battery pack according to the present invention may include a plurality of the battery modules according to the present invention described above. The battery pack according to the present invention may further include various other components in addition to the battery modules, for example, components of a battery pack known at the time of filing of the present invention, such as a BMS, a bus bar, a back case, a relay, a current sensor, etc.

[0114] The energy storage system according to the present invention may include one or more battery modules according to the present invention. In particular, the energy storage system may include a plurality of battery modules according to the present invention, electrically connected to each other to ensure a large energy capacity. Alternatively, a plurality of the battery modules according to the present invention may constitute a battery pack, and the energy storage system may be configured in a form including a plurality of such battery packs. In addition, the energy storage system according to the present invention may further include various other components of an energy storage system known at the time of filing of the present invention. Furthermore, the energy storage system may be used in various locations and devices, such as a smart grid system or an electric charging station.

[0115] In addition, although terms indicating directions such as up, down, left, right, front, and back are used in this specification, it will be obvious to those skilled in the art that these terms indicate relative positions and are used only for convenience of explanation, and may change depending on the position of the target object, the position of the observer, etc.

[0116] Although the present invention has been described above with reference to limited embodiments and drawings, it goes without saying that the present invention is not limited thereto, and various modifications and variations can be made by those having ordinary knowledge in the technical field to which the present invention pertains within the scope of the technical spirit of the present invention and the equivalent scope of the claims. [Explanation of symbols]

[0117] 100 Cell Assembly 110 Secondary battery 111 Electrode lead 200 module case 210 Lower Plate 220 Side Plate 220L Left side plate 220R right side plate 221 Trap section 222 Protrusion 230 Upper Plate 240 Front plate 250 rear plate 300 Busbar Assembly 310 Module Busbar 320 Busbar housing 321 Slots 400 Mesh material 500 Porous material P Cut-off protrusion

Claims

1. a cell assembly including a plurality of secondary batteries stacked on top of one another; a module case including a lower plate, a side plate, and an upper plate to form an internal space for accommodating the cell assembly, the module case including a trap portion formed by being recessed outward on at least a portion of an inner surface of the side plate; A battery module comprising: When a spark is ejected from the secondary battery, the ejected spark is trapped by the trap portion, At least one of a front and a rear of the module case is open, and gas generated in the cell assemblies moves through the trap portion and is discharged from at least one of the front and rear openings of the module case.

2. The battery module according to claim 1 , wherein the cell assembly is configured such that a plurality of pouch-type secondary batteries are vertically stacked in a horizontal state.

3. The battery module according to claim 2 , wherein the cell assembly is arranged such that electrode leads of the pouch-type secondary batteries are positioned in a front-rear direction of the module case.

4. The battery module according to claim 3 , further comprising a bus bar assembly located in the opening of the module case and configured to be coupled to the electrode lead.

5. The battery module according to claim 1 , wherein the trap portion is formed at least in a central portion in a front-rear direction of the side plate.

6. The battery module according to claim 1 , wherein the trap portion is formed such that at least a portion of the trap portion is recessed so that the depth of the recessed portion increases toward the front or rear.

7. The battery module according to claim 1 , wherein the module case further comprises a protrusion formed on at least one end of the trap portion so as to protrude toward a center.

8. The battery module according to claim 1 , wherein at least one end of the trap portion is formed to be recessed in a front-rear direction.

9. A battery pack comprising a plurality of battery modules according to any one of claims 1 to 8.

10. 9. An energy storage system comprising a battery module according to any one of claims 1 to 8.

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