Battery module including flame retardant sheet, battery rack and energy storage system including the battery module

Abstract

The present invention provides a battery module with a reduced risk of secondary fire or explosion. To achieve this purpose, the battery module according to the present invention includes: at least one monomer assembly, the at least one monomer assembly includes a plurality of secondary batteries, each of the secondary batteries has an electrode lead; a module housing, the module housing having an internal space, the internal space being formed to accommodate the monomer assembly therein; a busbar assembly, the busbar assembly including at least one busbar, at least one busbar frame and a flame retardant sheet, the busbar having conductivity, having a plate shape, and being formed so that a portion of the electrode lead contacts therewith; the busbar frame having insulation, having at least one busbar mounted thereon, and having a plurality of perforations, through which the electrode leads of the plurality of secondary batteries pass; the flame retardant sheet having a plate shape, and being positioned to be in close contact with the outer side of the busbar to seal the perforations.

Description

Technical Field

[0001] The present disclosure relates to a battery module including a flame-retardant sheet, and a battery rack and an energy storage system including the battery module. More particularly, the present disclosure relates to a battery pack with reduced risk of secondary fire or explosion.

[0002] This application claims priority from Korean Patent Application No. 10-2020-0005522 filed in Korea on January 15, 2020, the disclosure of which is incorporated herein by reference. Background Art

[0003] Currently commercialized secondary batteries include nickel-cadmium batteries, nickel-metal hydride batteries, nickel-zinc batteries and lithium secondary batteries. Among them, lithium secondary batteries have attracted much attention due to their advantages such as free charge and discharge due to almost no memory effect, extremely low self-discharge rate and high energy density compared to nickel-based secondary batteries.

[0004] Lithium secondary batteries mainly use lithium oxides and carbon materials as positive electrode active materials and negative electrode active materials, respectively. Lithium secondary batteries include: an electrode assembly in which a positive electrode plate and a negative electrode plate coated with positive electrode active materials and negative electrode active materials are provided, respectively, and a separator is placed between the positive electrode plate and the negative electrode plate; and an exterior, i.e., a battery bag exterior, which is used to seal and store the electrode assembly together with the electrolyte.

[0005] Recently, secondary batteries are widely used not only in small devices such as portable electronic devices, but also in medium or large devices such as vehicles and energy storage systems. When used in medium or large devices, a large number of secondary batteries are electrically connected to increase capacity and output. In particular, since pouch-type secondary batteries can be easily stacked, pouch-type secondary batteries are widely used in medium or large devices.

[0006] Meanwhile, recently, as demand for large-capacity structures increases with use as energy storage sources, demand for a battery module including a plurality of secondary batteries electrically connected in series and / or in parallel and a battery management system (BMS) is increasing.

[0007] In addition, the battery module generally includes a housing made of a metal material to protect or store a plurality of secondary batteries from external impacts. Meanwhile, the demand for high-capacity battery modules is increasing recently.

[0008] However, since a conventional battery rack has a plurality of battery modules, if a secondary battery of each battery module causes fire or explosion, heat or flame may be transferred to adjacent secondary batteries to cause a secondary explosion, and thus efforts to prevent the secondary fire or explosion are increasing.

[0009] In addition, in order to prevent the fire from spreading to the secondary battery adjacent to the secondary battery on fire, the generated flame and high temperature gas need to be quickly discharged to the outside. In addition, in order to quickly extinguish the fire of the secondary battery on fire, it is necessary to develop a technology that can block air so that oxygen is not supplied to the secondary battery on fire. Summary of the invention

[0010] Technical issues

[0011] The present disclosure is designed to solve the problems of the related art, and thus the present disclosure aims to provide a battery module that reduces the risk of secondary fire or explosion.

[0012] These and other purposes and advantages of the present disclosure can be understood from the following detailed description and will become more apparent from the exemplary embodiments of the present disclosure.In addition, it will be easily understood that the purposes and advantages of the present disclosure can be achieved by the means shown in the appended claims and their combinations.

[0013] Technical Solution

[0014] In one aspect of the present disclosure, there is provided a battery module, the battery module comprising:

[0015] at least one single cell assembly, the at least one single cell assembly comprising a plurality of secondary batteries, each of the plurality of secondary batteries having an electrode lead;

[0016] a module housing having an internal space formed to accommodate the cell assembly therein;

[0017] a bus bar assembly comprising at least one conductive bus bar having a plate shape and configured to contact a portion of the electrode lead, and at least one electrically insulating bus bar frame, the at least one bus bar being mounted to the at least one electrically insulating bus bar frame, the at least one bus bar frame having a plurality of through holes through which the electrode leads of the plurality of secondary batteries pass; and

[0018] A flame retardant sheet has a plate shape and is positioned to be in close contact with the outer side of the bus bar to close the penetration hole.

[0019] In addition, the flame-retardant sheet may have a plurality of welding holes through which a portion of the electrode lead in contact with the bus bar is exposed to the outside.

[0020] Also, the flame retardant sheet may have a ridge portion formed on an inner surface of the flame retardant sheet facing the bus bar to be ridged inwardly, the ridge portion being shaped to surround an outer periphery of the welding hole.

[0021] In addition, the plurality of secondary batteries may be stacked on each other in a front-rear direction, and configured to include electrode leads respectively located at left and right ends of the plurality of secondary batteries.

[0022] In addition, the bus bar assemblies may be respectively disposed at left and right sides of the cell assembly.

[0023] Also, the bus bar may have an insertion hole formed therein to communicate with the penetration hole.

[0024] Furthermore, the busbar frame may include:

[0025] a main body portion having a plate shape such that the at least one bus bar is mounted to an outer surface of the main body portion and configured to extend in a direction in which the plurality of secondary batteries are stacked; and

[0026] At least two fixing portions are configured to protrudely extend outward from the main body portion to be coupled to the flame-retardant sheet.

[0027] In addition, the flame-retardant sheet may be inserted to be placed between the at least two fixing portions.

[0028] In addition, the flame-retardant sheet may further include a protrusion formed to protrude inwardly so that a portion of the protrusion is inserted into the insertion hole of the bus bar.

[0029] Furthermore, the fixing portion may have a fixing hole into which the outer periphery of the flame-retardant sheet is inserted.

[0030] Furthermore, the fixing portion may have at least one fixing protrusion formed to press the outer circumference of the flame retardant sheet inwardly so as to fix the flame retardant sheet.

[0031] In addition, the battery module may further include a pressing pin configured to press a portion of the flame-retardant sheet facing the insertion hole of the bus bar.

[0032] In another aspect of the present invention, a battery rack is provided, comprising at least one battery module.

[0033] In another aspect of the present invention, an energy storage system is provided. The energy storage system includes at least one battery rack.

[0034] Beneficial effects

[0035] According to an embodiment of the present disclosure, since the flame retardant sheet having a plate shape is positioned to be in close contact with the outer side of the bus bar mounted to the bus bar frame to close the through hole formed in the bus bar frame, if a fire occurs at the cell assembly, oxygen can be prevented from being supplied through the through hole of the bus bar assembly. Moreover, the flame retardant sheet can prevent the flame generated by the heat dissipation of the cell assembly or the fire from blasting to other adjacent internal components.

[0036] In addition, according to an embodiment of the present disclosure, since the flame-retardant sheet includes a ridge formed on its inner surface facing the bus bar, the ridge has an inwardly ridged shape and is formed to surround the periphery of the welding hole, it is possible to prevent air from entering the interior from the outside through the welding hole of the flame-retardant sheet.

[0037] In addition, according to an embodiment of the present disclosure, since the fixing portion has a fixing hole configured so that the outer periphery of the flame retardant sheet is inserted into the fixing hole, the flame retardant sheet can be easily fixed to the bus bar frame. Moreover, after the flame retardant sheet is inserted into the bus bar frame, even if an external impact is applied to the flame retardant sheet, the flame retardant sheet can be prevented from detaching from the bus bar frame. Therefore, the durability of the battery module can be increased.

[0038] In addition, according to an embodiment of the present invention, since the present invention further includes a squeezing pin, which is configured to squeeze inwardly a portion of the insertion hole of the flame retardant sheet facing the busbar, the squeezing pin can normally make the flame retardant sheet in close contact with the busbar, so that the perforations of the busbar frame are closed. At the same time, when a fire or heat dissipation occurs at a cell assembly, the squeezing pin can flexibly allow the high-pressure gas ejected by the internal pressure to be discharged through the perforations and insertion holes of the busbar frame while pushing the flame retardant sheet outward. Therefore, it is possible to prevent external air from being introduced into the cell assembly while discharging the high-temperature gas of the cell assembly, thereby preventing the fire or heat dissipation of the battery module from spreading to other adjacent cell assemblies. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The accompanying drawings illustrate preferred embodiments of the present disclosure and, together with the foregoing disclosure, are used to provide a further understanding of the technical features of the present disclosure. Therefore, the present disclosure is not interpreted as being limited to the accompanying drawings.

[0040] Figure 1 is a perspective view schematically showing a battery module according to an embodiment of the present disclosure.

[0041] Figure 2 is an exploded perspective view schematically showing components of a battery module according to an embodiment of the present disclosure.

[0042] Figure 3is a perspective view schematically illustrating components of a battery module according to an embodiment of the present disclosure.

[0043] Figure 4 is a side view schematically showing a bus bar frame employed at a battery module according to an embodiment of the present disclosure.

[0044] Figure 5 It is schematically shown Figure 3 A partial side view of the inner surface of a battery module.

[0045] Figure 6 is a right side view schematically showing a flame retardant sheet used at a battery module according to an embodiment of the present disclosure.

[0046] Figure 7 is a perspective view schematically showing a flame-retardant sheet used in a battery module according to another embodiment of the present disclosure.

[0047] Figure 8 is a perspective view schematically showing a flame-retardant sheet used in a battery module according to another embodiment of the present disclosure.

[0048] Fig. 9 is a partial side view schematically showing a side surface of a battery module according to still another embodiment of the present disclosure.

[0049] Fig.10 is a partial side view schematically showing a side surface of a battery module according to still another embodiment of the present disclosure.

[0050] Fig.11 is a partial side view schematically showing a side surface of a battery module according to still another embodiment of the present disclosure.

[0051] Fig.12 is schematically shown in Fig.11 A three-dimensional image of the squeeze pins used in the battery module.

[0052] Fig.13 is a perspective view schematically showing an energy storage system according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0053] Hereinafter, preferred embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. Before the description, it should be understood that the terms used in the specification and the appended claims should not be interpreted as limited to the general meaning and dictionary meaning, but based on the principle of allowing the inventor to appropriately define the terms to obtain the best interpretation, based on the meaning and concept corresponding to the technical aspects of the present disclosure.

[0054] Therefore, the descriptions presented herein are only preferred examples for illustrative purposes, and are not intended to limit the scope of the present disclosure, and it should be understood that other equivalent schemes and modifications may be made thereto without departing from the scope of the present invention.

[0055] Figure 1 is a perspective view schematically showing a battery module according to an embodiment of the present disclosure. Figure 2 is an exploded perspective view schematically showing components of a battery module according to an embodiment of the present disclosure. Figure 3 is a perspective view schematically showing components of a battery module according to an embodiment of the present disclosure. Figure 3 In order to show the interior of the battery module 200, the battery module 200 is shown in a state where the upper cover 220 of the module housing 210 is not included. Figure 2 , the positive direction arrow of the X-axis points to the right direction, and the negative direction thereof points to the left direction, the positive direction arrow of the Y-axis points to the rear direction, and the negative direction thereof points to the front direction, and the positive direction arrow of the Z-axis points to the upper direction, and the negative direction thereof points to the lower direction.

[0056] Reference Figures 1 to 3 , the battery module 200 according to an embodiment of the present disclosure may include a cell assembly 100 , a module case 210 , and a flame-retardant sheet 230 .

[0057] Here, the cell assembly 100 may include a plurality of secondary batteries 110 stacked on each other in a front-rear direction. The secondary batteries 110 may be pouch-type secondary batteries 110. For example, Figure 2 As shown, each of the two cell assemblies 100 may be configured such that 21 pouch-type secondary batteries 110 are stacked side by side in the front-rear direction (Y-axis direction).

[0058] In particular, the pouch type secondary battery 110 may include an electrode assembly (not shown), an electrolyte (not shown), and a pouch 116 .

[0059] When in the F direction ( Figure 1 When viewed from the top (as shown in FIG. 1 ), the secondary battery 110 may be arranged to stand approximately perpendicular to the ground (Z-axis direction), so that the two wide sides of the secondary battery 110 are located at the front and rear sides, respectively, and the sealing portion is located at the upper side, the lower side, the left side, and the right side. In other words, each secondary battery 110 may be configured to stand upright in the vertical direction. Meanwhile, in this specification, unless otherwise specified, the upper direction, the lower direction, the front direction, the rear direction, the left direction, and the right direction will be set based on when viewed in the F direction.

[0060] Here, the bag 116 may be configured as a bag having a concave receiving portion. In addition, the electrode assembly and the electrolyte may be received in the receiving portion. In addition, each of the bags may include an outer insulating layer, a metal layer, and an inner adhesive layer, and the inner adhesive layer may be bonded to each other at the edge of the bag to form the sealing portion. In addition, a platform portion may be formed at each end of the secondary battery 110 in the left-right direction (X-axis direction) where the positive lead 111a and the negative lead 111b are formed.

[0061] In addition, the electrode assembly is an assembly of an electrode plate coated with an electrode active material and a separator, and may be configured such that at least one positive electrode plate and at least one negative electrode plate are disposed such that the separator is interposed therebetween. In addition, the positive electrode tab may be disposed at the positive electrode plate of the electrode assembly, and the at least one positive electrode tab may be connected to the positive electrode lead 111a.

[0062] Here, one end of the positive lead 111 a may be connected to the positive electrode tab and the other end may be exposed outside the pouch 116 , and the exposed portion may serve as an electrode lead of the secondary battery 110 , for example, a positive terminal of the secondary battery 110 .

[0063] In addition, a negative electrode tab is provided at the negative electrode plate of the electrode assembly, and the one negative electrode tab may be connected to the negative electrode lead 111b. In addition, one end of the negative electrode lead 111b may be connected to the negative electrode tab, while the other end is exposed outside the bag, and the exposed portion may be used as an electrode lead of the secondary battery 110, for example, a negative terminal of the secondary battery 110.

[0064] In addition, if Figure 1 As shown, when directly viewed in the F direction, the positive electrode lead 111a and the negative electrode lead 111b may be formed at the left and right ends in opposite directions (X-axis direction) relative to the center of the secondary battery 110. That is, the positive electrode lead 111a may be disposed at one end (left end) based on the center of the secondary battery 110. In addition, the negative electrode lead 111b may be disposed at the other end (right end) based on the center of the secondary battery 110.

[0065] For example, Figure 2 As shown, each secondary battery 110 of the cell assembly 100 may be configured such that the positive electrode lead 111 a and the negative electrode lead 111 b protrude in the left-right direction.

[0066] Here, terms indicating directions such as "front", "rear", "left", "right", "up", and "down" may vary depending on the position of the observer or the shape of the object. However, in this specification, for convenience of description, directions such as front, rear, left, right, up, and down are shown individually based on when viewed in the F direction.

[0067] Here, terms indicating directions such as "front", "rear", "left", "right", "up", and "down" used in this specification may vary depending on the position of the observer or the form of the object placed. However, in this specification, for convenience of description, directions such as "front", "rear", "left", "right", "up", and "down" are expressed distinguishably based on the case of viewing in the F direction.

[0068] Therefore, according to such a configuration of the present disclosure, in one secondary battery 110 , there is no interference between the positive electrode lead 111 a and the negative electrode lead 111 b , and thus the area of ​​the electrode lead 111 can be increased.

[0069] In addition, the positive electrode lead 111a and the negative electrode lead 111b may be configured in a plate shape. Specifically, the positive electrode lead 111a and the negative electrode lead 111b may protrude in the horizontal direction (X-axis direction) with their wide sides standing toward the front-rear direction.

[0070] Here, the horizontal direction may refer to a direction parallel to the ground when the secondary battery 110 is placed on the ground, and may also refer to at least one direction on a plane perpendicular to the vertical direction.

[0071] However, the battery module 200 according to the present disclosure is not limited to the above-mentioned pouch-type secondary battery 110 , but may employ various secondary batteries 110 known at the time of filing the present application.

[0072] In addition, at least two or more single body assemblies 100 may be arranged in the front-rear direction. Figure 2 As shown, two single body assemblies 100 may be arranged in the front-rear direction, and the two single body assemblies 100 may be spaced apart from each other by a predetermined distance.

[0073] Meanwhile, the module case 210 may have an inner space to accommodate the cell assembly 100 therein. Specifically, the module case 210 may include an upper cover 220 , a bottom plate 255 , a front cover 250 , and a rear cover 260 .

[0074] Specifically, the bottom plate 255 may have an area greater than the size of the bottom surface of the at least two monomer assemblies 100 to mount the at least two monomer assemblies 100 to the upper portion of the bottom plate 255. The bottom plate 255 may have a plate shape extending in a horizontal direction.

[0075] In addition, the upper cover 220 may include a top 224 and a side 226. The top 224 may have a plate shape extending in a horizontal direction to cover the upper portion of the monomer assembly 100. The side 226 may have a plate shape extending downward from left and right ends of the top 224 to cover left and right sides of the monomer assembly 100.

[0076] In addition, the side portion 226 may be coupled to a portion of the bottom plate 255. For example, Figure 2 As shown, the upper cover 220 may include a top 224 having a plate shape extending in the front, rear, left and right directions. The upper cover 220 may include two side portions 226 extending downward from the left and right ends of the top 224, respectively. In addition, the lower ends of the two side portions 226 may be configured to be respectively coupled to the left and right ends of the bottom plate 255. In this case, the coupling method may be a male-female coupling method or a welding method.

[0077] In addition, the side portion 226 may have a curling portion B1 that protrudes inward toward the secondary battery 110. Figure 2 As shown, eight bead portions B1 protruding inwardly may be formed on one side portion 226 .

[0078] In addition, the front cover 250 may be configured to cover the front sides of the plurality of secondary batteries 110. For example, the front cover 250 may have a plate shape larger than the size of the front surfaces of the plurality of secondary batteries 110. The plate shape may stand in a vertical direction.

[0079] In addition, a portion of the outer circumference of the front cover 250 may be coupled to the bottom plate 255. For example, a lower portion of the outer circumference of the front cover 250 may be coupled to a front end of the bottom plate 255. In addition, an upper portion of the outer circumference of the front cover 250 may be coupled to a front end of the upper cover 220. Here, the coupling method may adopt bolt connection.

[0080] In addition, the back cover 260 may be configured to cover the rear side of the cell assembly 100. For example, the back cover 260 may have a plate shape larger than the size of the rear surfaces of the plurality of secondary batteries 110.

[0081] In addition, a portion of the outer periphery of the rear cover 260 may be coupled to the bottom plate 255. For example, a lower portion of the outer periphery of the rear cover 260 may be coupled to the front end of the bottom plate 255. In addition, an upper portion of the outer periphery of the rear cover 260 may be coupled to the rear end of the upper cover 220. Here, the coupling method may be bolted. The rear cover 260 may have a discharge hole 264h formed to allow external air to flow to the inside or allow internal air to flow to the outside.

[0082] Therefore, according to such a configuration of the present disclosure, since the module case 210 has a structure capable of stably protecting the plurality of secondary batteries 110 from external impact, the safety of the battery module 200 against external impact can be improved.

[0083] Meanwhile, the battery module 200 of the present disclosure may further include a module BMS 290 configured to control the charging and discharging of the cell assembly 100. The module BMS 290 may include various sensors and circuits to sense the temperature and current of the battery module 200. The sensors and circuits are not shown in the figure.

[0084] In addition, the battery module 200 of the present disclosure may include a flame retardant sheet 280. The flame retardant sheet may be located between two cell assemblies 100. The flame retardant sheet 280 may have openings 286 formed at left and right sides thereof so that air may pass through the openings 286.

[0085] Meanwhile, the bus bar assembly 270 may include at least one bus bar 272 and at least one bus bar frame 276 to which the bus bar 272 is mounted.

[0086] Specifically, the bus bar 272 may be an alloy containing a metal having excellent electrical conductivity such as copper, nickel, or aluminum. The bus bar 272 may be configured to electrically connect the plurality of secondary batteries 110 to each other. That is, the bus bar 272 may be configured to contact a portion of the electrode lead 111. The bus bar 272 may have a plate shape. For example, Figure 2 As shown, the bus bar 272 may have a plate shape extending in the front-rear direction and the up-down direction.

[0087] In addition, the bus bar frame 276 may include an electrically insulating material. For example, the bus bar frame 276 may include a plastic material. More specifically, the plastic material may be polycarbonate, polyvinyl chloride, or the like.

[0088] For example, Figure 2 As shown, the battery module 200 may include four bus bar assemblies 270. The bus bar assemblies 270 may be located on the left and right sides of the cell assembly 100, respectively. Each of the four bus bar assemblies 270 may include a bus bar frame 276 and four bus bars 272, and the bus bar frame 276 is configured such that the four bus bars 272 are mounted to the outer surface of the bus bar frame 276.

[0089] Figure 4 is a side view schematically showing a busbar frame used at a battery module according to an embodiment of the present disclosure. In addition, Figure 5 It is schematically shown Figure 3 A partial side view of the inner surface of a battery module.

[0090] Reference Figure 4 and Figure 5 as well as Figure 2 , the busbar frame 276 may include a main body 276a and at least two fixing parts 276b. The main body 276a may have a plate shape so that the at least one busbar 272 is mounted to the outer surface of the main body 276a. The main body 276a may stand upright in a vertical direction. The main body 276a may be elongated in a direction (front-rear direction) in which a plurality of secondary batteries 110 are stacked.

[0091] In addition, the fixing portion 276b may have a shape protrudingly extending outward from the main body portion 276a. The fixing portion 276b may have a shape protrudingly extending outward from the upper and lower portions of the outer surface of the main body portion 276a.

[0092] In addition, the fixing portion 276b may be configured to be coupled to the flame retardant sheet 230. For example, the flame retardant sheet 230 may be configured to be placed between two fixing portions 276b. For example, the flame retardant sheet 230 may be inserted between a fixing portion 276b formed at an upper portion of the main body portion 276a and a fixing portion 276b formed at a lower portion of the main body portion 276a, and assembled to the fixing portions by assembly.

[0093] In addition, the busbar frame 276 of the battery module 200 of the present disclosure may have a plurality of penetration holes H1 through which the electrode leads 111 of the plurality of secondary batteries 110 pass. Figure 4 As shown, the busbar frame 276 may have perforations H1 respectively formed at positions corresponding to the electrode leads 111 of the plurality of secondary batteries 110. Therefore, each electrode lead 111 of the plurality of secondary batteries 110 of the cell assembly 100 may be configured to protrude outward through the perforations H1 of the busbar frame 276. The perforations H1 may have a shape similar to that of the electrode leads 111. For example, the perforations H1 may have rectangular holes elongated in the vertical direction.

[0094] In addition, the bus bar 272 may have an insertion hole H2 configured to communicate with the through hole H1. The insertion hole H2 may be configured such that the electrode lead 111 of the secondary battery 110 is inserted into the insertion hole H2. Figure 5, five insertion holes H2 may be formed in any one of the bus bars 272. The electrode lead 111 of the secondary battery 110 may be inserted into each of the five insertion holes H2, and the inserted portion may be bent in the front-rear direction to contact (weld to) the outer surface of the bus bar 272.

[0095] In addition, the flame retardant sheet 230 may include a flame retardant material that is not easily burnt, such as mica, chlorinated vinyl chloride resin, chlorinated paraffin, decabromodiphenyl ether, antimony trioxide, and the like.

[0096] In addition, the flame retardant sheet 230 may have a plate shape. That is, the flame retardant sheet 230 may have a sheet shape extending in the front-rear direction and the up-down direction. In addition, the flame retardant sheet 230 may be configured to close the perforation H1. The flame retardant sheet 230 may be positioned to be in close contact with the outer side of the bus bar 272. That is, the flame retardant sheet 230 may be fixed at a position facing the perforation H1 of the bus bar frame 276.

[0097] Therefore, according to such a configuration of the present disclosure, since the flame-retardant sheet 230 having a plate shape is positioned to be in close contact with the outer side of the bus bar 272 mounted to the bus bar frame 276 to close the through hole H1 formed in the bus bar frame 276, if a fire occurs at the cell assembly 100, it is possible to prevent oxygen from being supplied through the through hole H1 of the bus bar assembly 270. In addition, the flame-retardant sheet 230 can prevent the flame generated by the heat dissipation of the cell assembly 100 or the fire from blasting to other adjacent internal components.

[0098] Figure 6 is a right side view schematically showing a flame retardant sheet used at a battery module according to an embodiment of the present disclosure.

[0099] Reference Figure 6 and Figure 5 , the flame retardant sheet 230 may be formed with a plurality of welding holes G1. The welding holes G1 may be formed by punching a portion of the flame retardant sheet 230 so that a portion of the electrode lead 111 in contact with the bus bar 272 may be exposed to the outside. The plurality of welding holes G1 may be formed at positions corresponding to the welding portions of the electrode lead 111 and the bus bar 272. For example, Figure 6 As shown, a plurality of welding holes G1 may be formed in each of the four flame-retardant sheets 230 so that a portion of the electrode lead 111 contacting the bus bar 272 is exposed to the outside.

[0100] Therefore, according to this configuration of the present disclosure, since the flame-retardant sheet 230 has a plurality of perforated welding holes G1, a portion of the electrode lead 111 that contacts the bus bar 272 is exposed to the outside, even when the flame-retardant sheet 230 is located on the bus bar 272 of the bus bar assembly 270, the contact portion of the bus bar 272 and the electrode lead 111 can be welded through the plurality of welding holes G1. Therefore, it is possible to prevent the manufacturing efficiency from being reduced due to the flame-retardant sheet 230.

[0101] Figure 7 is a perspective view schematically showing a flame-retardant sheet used in a battery module according to another embodiment of the present disclosure.

[0102] Reference Figure 7 and Figure 5 ,and Figure 6 Compared with the flame-retardant sheet 230 of the battery module according to another embodiment, the flame-retardant sheet 230A of the battery module according to another embodiment may further include a ridge 233 located on the inner surface 230a. Specifically, the ridge 233 may be formed on the inner surface of the flame-retardant sheet 230A. The ridge 233 may have a shape protruding inwardly. For example, the ridge 233 may be configured to be in close contact with the outer surface of the bus bar 272. The ridge 233 may have a shape surrounding the periphery of the welding hole G1.

[0103] For example, Figure 7 As shown, 18 welding holes G1 may be formed in the flame retardant sheet 230A. The ridge 233 may be formed at each of the 18 welding holes G1. The ridge 233 may protrude inwardly and be in close contact with the outer surface of the bus bar 272 to prevent a gap from being generated between the flame retardant sheet 230A and the bus bar 272.

[0104] Therefore, according to this construction of the present disclosure, since the flame-retardant sheet 230A includes a ridge 233 formed on its inner surface facing the bus bar 272, the ridge 233 has an inwardly ridged shape and is formed to surround the periphery of the welding hole G1, it is possible to prevent air from entering the interior from the outside through the welding hole G1 of the flame-retardant sheet 230A.

[0105] Figure 8 is a perspective view schematically showing a flame-retardant sheet used in a battery module according to another embodiment of the present disclosure.

[0106] Reference Figure 8 and Figure 5 ,and Figure 6Compared with the flame-retardant sheet 230 of the battery module according to another embodiment, the flame-retardant sheet 230B of the battery module according to another embodiment may further include a protrusion 235 located on the inner surface 230a. Specifically, the protrusion 235 may have a shape protruding inward by a predetermined length, so that a portion of the protrusion 235 is inserted into the insertion hole H2 of the bus bar 272. For example, Figure 8 As shown, the flame retardant sheet 230B may have five protrusions 235. The protrusions 235 may be formed at the through holes H1 ( Figure 4 ) corresponding to the position. In addition, the protrusion 235 may be configured to be inserted into the insertion hole H2 ( Figure 5 )middle.

[0107] Therefore, according to this configuration of the present disclosure, since the flame retardant sheet 230B includes the protrusion 235 protruding inwardly, so that a portion of the protrusion 235 is inserted into the insertion hole H2 of the bus bar 272, it is possible to prevent air from being introduced into the interior from the outside through the insertion hole H2 communicating with the through hole H1. Figure 2 ), the battery module of the present disclosure can also prevent air from flowing into the interior, thereby preventing the fire or heat dissipation from spreading to other adjacent single cell assemblies 100 ( Figure 2 ).

[0108] Fig. 9 is a partial side view schematically showing a side surface of a battery module according to still another embodiment of the present disclosure.

[0109] Reference Fig. 9 According to another embodiment, the busbar frame 276C of the battery module 200C may have a fixing hole 276h formed in the fixing portion 276b. The fixing hole 276h may be configured so that a portion 272a of the outer periphery of the flame retardant sheet 230C is inserted into the fixing hole 276h. For example, Fig. 9 As shown, a fixing portion 276b protruding outward from the main body portion 276a may be provided in the busbar frame 276C. In a portion of the fixing portion 276b, the fixing hole 276h may be formed to be perforated in the vertical direction. The upper portion 272a of the periphery of the flame retardant sheet 230C may have a shape protruding upward to be inserted into the fixing hole 276h. The upper and lower portions 272a of the periphery of the flame retardant sheet 230C may have a shape protruding downward to be inserted into the fixing hole 276h formed in the fixing portion 276b located below.

[0110] Therefore, according to such a configuration of the present disclosure, since the fixing portion 276b has the fixing hole 276h configured so that the outer periphery of the flame retardant sheet 230C is inserted therein, the flame retardant sheet 230C can be easily fixed to the bus bar frame 276C. In addition, after the flame retardant sheet 230C is inserted into the bus bar frame 276C, even if an external impact is applied to the flame retardant sheet 230C, the flame retardant sheet 230C can be prevented from being detached from the bus bar frame 276C. Therefore, the durability of the battery module 200C can be improved.

[0111] Fig.10 is a partial side view schematically showing a side surface of a battery module according to still another embodiment of the present disclosure.

[0112] Reference Fig.10 According to another embodiment, the busbar frame 276D of the battery module 200D may further include at least one fixing protrusion 276p formed on the fixing portion 276b. The fixing protrusion 276p may be configured to press the outer periphery of the flame retardant sheet 230 inwardly so as to fix the flame retardant sheet 230. That is, the fixing protrusion 276p may have a shape extending from the fixing portion 276b to contact the outer surface of the flame retardant sheet 230, thereby pressing the outer surface of the flame retardant sheet 230 inwardly.

[0113] For example, Fig.10 As shown, the fixing protrusion 276p may be formed on each of the two fixing portions 276b of the busbar frame 276. The fixing protrusion 276p protruding downward may be formed on the fixing portion 276b located at the upper portion of the busbar frame 276. The fixing protrusion 276p protruding upward may be formed on the fixing portion 276b located at the lower portion of the busbar frame 276. The fixing protrusion 276p formed on the fixing portion 276b may be configured to press the outer periphery of the flame retardant sheet 230 inwardly.

[0114] Therefore, according to such a configuration of the present disclosure, since the fixing portion 276b has at least one fixing protrusion 276p configured to press and fix the outer periphery of the flame-retardant sheet 230 inwardly, the flame-retardant sheet 230 can be easily fixed to the bus bar frame 276. Moreover, after the flame-retardant sheet 230 is inserted into the bus bar frame 276, even if an external impact is applied to the flame-retardant sheet 230, the flame-retardant sheet 230 can be prevented from being detached from the bus bar frame 276. Therefore, the durability of the battery module 200D can be improved.

[0115] Fig.11 is a partial side view schematically showing a side surface of a battery module according to another embodiment of the present disclosure. In addition, Fig.12 is schematically shown in Fig.11 A three-dimensional image of the squeeze pins used in the battery module.

[0116] Together with Figure 5 Reference Fig.11 and Fig.12 ,and Figure 6 Compared to the battery module 200 of the embodiment of the present invention, the battery module 200E according to another exemplary embodiment may further include a pressing pin 240. Specifically, the pressing pin 240 may be configured to press a portion S1 of the flame-retardant sheet 230 facing the insertion hole H2 of the bus bar 272. For example, one flame-retardant sheet 230 may have five portions S1 facing the insertion hole H2 of the bus bar 272. Each of the five pressing pins 240 may press a portion S1 of the flame-retardant sheet 230 facing the insertion hole H2 of the bus bar 272 inwardly.

[0117] In addition, the extrusion pin 240 may include an extrusion portion 245 and a connection portion 241. The connection portion 241 may be configured to be assembled into an end portion of a fixing portion 276b formed at the busbar frame 276. For example, the connection portion 241 may have a clip shape. The extrusion portion 245 may be a portion that extends from the connection portion 241 to a portion of the flame-retardant sheet 230 that faces the insertion hole H2 of the busbar 272. The extrusion portion 245 may elastically press the outer surface of the flame-retardant sheet 230 inwardly. To this end, the extrusion portion 245 may have a structure K1 that is bent in at least one direction.

[0118] Therefore, according to this configuration of the present disclosure, since the present disclosure further includes a pressing pin 240, which is configured to press the portion of the insertion hole H2 of the flame retardant sheet 230 facing the bus bar 272 inward at normal times, the pressing pin 240 can make the flame retardant sheet 230 in close contact with the bus bar 272, so that the perforation H1 of the bus bar frame 276 is closed. At the same time, when a fire or heat dissipation occurs at the cell assembly 100, the pressing pin 240 can flexibly allow the high-pressure gas ejected by the internal pressure to be discharged through the perforation H1 and the insertion hole H2 of the bus bar frame 276 while pushing the flame retardant sheet 230 outward. Therefore, it is possible to prevent external air from being introduced into the cell assembly 100 while discharging the high-temperature gas of the cell assembly 100, thereby preventing the fire or heat dissipation of the battery module 200E from spreading to other adjacent cell assemblies 100.

[0119] Fig.13 is a perspective view schematically showing an energy storage system according to an embodiment of the present disclosure.

[0120] Reference Fig.13 and Figure 2 , the battery rack 300 according to the present disclosure may further include a battery rack BMS (Battery Management System) 330 disposed inside or outside the battery rack housing 310 to exchange information with the plurality of module BMSs 290 .

[0121] The energy storage system according to the present disclosure may include at least one battery rack 300 according to the present disclosure. In particular, the energy storage system may include a plurality of battery racks 300 according to the present disclosure. In addition, the plurality of battery racks 300 may be electrically connected to each other. The energy storage system according to the present disclosure may be implemented in various forms, such as a smart grid system or a charging station.

[0122] At the same time, although terms indicating directions such as up, down, left, right, front and rear are used in the specification, it is obvious to those skilled in the art that these terms are only used to indicate relative positions for convenience of description and may vary based on the position of the observer or the object.

[0123] The present disclosure has been described in detail. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the present disclosure, are given by way of illustration only, since various changes and modifications within the scope of the present disclosure will become apparent to those skilled in the art from this detailed description.

[0124] Reference numerals

[0125] 200: Battery module 100: Single cell assembly

[0126] 110: Secondary battery 210: Module housing

[0127] 270: Busbar assembly

[0128] 272, 276: Busbar, busbar frame

[0129] H1: Through hole H2: Insert hole

[0130] 276a: Main body 276b: Fixed part

[0131] 276h: Fixing hole 276p: Fixing protrusion

[0132] 230: Flame retardant sheet

[0133] G1: Welding hole 233: Ridge

[0134] 235: protrusion 240: extrusion pin

[0135] 300: Battery rack 310: Battery rack housing

Claims

1. A battery module, comprising: at least one single cell assembly, the at least one single cell assembly comprising a plurality of secondary batteries, each of the plurality of secondary batteries having an electrode lead; a module housing having an internal space formed to accommodate the cell assembly therein; a bus bar assembly, the bus bar assembly comprising at least one conductive bus bar having a plate shape and configured to contact a portion of the electrode lead, and at least one electrically insulating bus bar frame, the at least one conductive bus bar being mounted to the at least one electrically insulating bus bar frame, the at least one electrically insulating bus bar frame having a plurality of through holes through which the electrode leads of the plurality of secondary batteries pass; and a flame retardant sheet having a plate shape and positioned to be in close contact with the outer side of the conductive bus bar to close the through hole, The flame-retardant sheet has a plurality of welding holes, and a portion of the electrode lead in contact with the conductive bus bar is exposed to the outside through the plurality of welding holes.

2. The battery module according to claim 1, wherein: The flame retardant sheet has a ridge portion formed on an inner surface of the flame retardant sheet facing the conductive bus bar to be ridged inwardly, the ridge portion being shaped to surround an outer periphery of the welding hole.

3. A battery module, comprising: at least one single cell assembly, the at least one single cell assembly comprising a plurality of secondary batteries, each of the plurality of secondary batteries having an electrode lead; a module housing having an internal space formed to accommodate the cell assembly therein; a bus bar assembly, the bus bar assembly comprising at least one conductive bus bar having a plate shape and configured to contact a portion of the electrode lead, and at least one electrically insulating bus bar frame, the at least one conductive bus bar being mounted to the at least one electrically insulating bus bar frame, the at least one electrically insulating bus bar frame having a plurality of through holes through which the electrode leads of the plurality of secondary batteries pass; and a flame retardant sheet having a plate shape and positioned to be in close contact with the outer side of the conductive bus bar to close the through hole, wherein the plurality of secondary batteries are stacked on each other in a front-rear direction and are configured to include electrode leads respectively located at left and right ends of the plurality of secondary batteries, The bus bar assemblies are respectively disposed at the left and right sides of the single body assembly, The conductive bus bar has an insertion hole formed therein to communicate with the through hole, The electrically insulating busbar frame comprises: a main body portion having a plate shape such that the at least one conductive bus bar is mounted to an outer surface of the main body portion and the main body portion is configured to extend in a direction in which the plurality of secondary batteries are stacked; and at least two fixing portions configured to protrude outwardly from the main body portion to be coupled to the flame retardant sheet, The flame-retardant sheet is inserted to be placed between the at least two fixing portions.

4. The battery module according to claim 3, wherein: The flame-retardant sheet further includes a protrusion formed to protrude inwardly so that a portion of the protrusion is inserted into the insertion hole of the conductive bus bar.

5. The battery module according to claim 4, wherein: The fixing portion has a fixing hole into which the outer periphery of the flame-retardant sheet is inserted.

6. The battery module according to claim 4, wherein: The fixing portion has at least one fixing protrusion formed to press the outer circumference of the flame retardant sheet inwardly so as to fix the flame retardant sheet. 7 . The battery module according to claim 4 , further comprising a pressing pin configured to press a portion of the flame-retardant sheet facing the insertion hole of the conductive bus bar.

8. A battery rack comprising at least one battery module according to any one of claims 1 to 7.

9. An energy storage system comprising at least one battery rack according to claim 8.

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