Battery rack and energy storage system including the battery rack

Abstract

The present invention provides a battery rack that, when a fire or thermal runaway occurs in any one of a plurality of battery packs, can effectively prevent the fire or heat from spreading to other adjacent battery packs. To this end, the battery rack according to the present invention includes: a plurality of battery packs; and a rack housing, the rack housing including a receiving space and a stopper disposed in the receiving space, wherein the plurality of battery packs are vertically mounted in the receiving space while being spaced apart from each other, the receiving space having an open structure to allow vertical communication between the plurality of battery packs, the stopper being positioned between the plurality of battery packs to be spaced apart from the plurality of battery packs, and the stopper being configured to suppress volume expansion of the battery packs in the event of volume expansion of the battery packs.

Description

Technical Field

[0001] The present disclosure relates to a battery rack and an energy storage system including the battery rack. More particularly, the present disclosure relates to a battery rack that is configured to effectively prevent fire or heat from spreading to adjacent battery packs when fire or thermal runaway occurs in any one of a plurality of battery packs.

[0002] This application claims the benefit of Korean Patent Application No. 10-2020-0037032, filed on March 26, 2020, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety. Background Art

[0003] Currently, commercially available secondary batteries include nickel-cadmium batteries, nickel-metal hydride batteries, nickel-zinc batteries, lithium secondary batteries, etc. Among them, lithium secondary batteries have almost no memory effect. Therefore, due to the advantages of lithium secondary batteries that can be recharged at any convenient time, have a very low self-discharge rate and high energy density, lithium secondary batteries are gaining more attention than nickel secondary batteries.

[0004] Lithium secondary batteries primarily use lithium oxides and carbon materials as the positive and negative electrode active materials, respectively. These batteries include an electrode assembly comprising positive and negative electrode plates coated with the positive and negative electrode active materials, respectively, with a separator interposed between the positive and negative electrode plates; and a package or battery pouch housing in which the electrode assembly, along with an electrolyte solution, is hermetically housed.

[0005] Recently, secondary batteries have been widely used not only in small devices such as portable electronic devices, but also in medium- and large-sized devices such as vehicles and energy storage systems. To be used in these applications, many secondary batteries are electrically connected to increase capacity and output. Pouch-type secondary batteries, in particular, are widely used in these devices due to their ease of stacking.

[0006] Recently, with the use as an energy source and the growing need for large-capacity structures, the demand for a battery rack is increasing, which includes: a plurality of secondary batteries electrically connected in series and / or parallel; a battery pack in which the plurality of secondary batteries are received; and a battery management system (BMS).

[0007] Generally, a battery rack includes a metal battery rack housing to protect a plurality of battery packs from external impact or to receive and store the battery packs. Recently, as demand for high-capacity battery racks increases, demand for battery racks including a plurality of battery packs is increasing.

[0008] However, when thermal runaway or fire occurs in a secondary battery of any one of a plurality of battery packs of a battery rack, the thermal runaway or fire may spread due to heat transfer to an adjacent battery pack, and thus many attempts have been made to prevent this.

[0009] In particular, a battery pack experiencing thermal runaway or fire may contact adjacent battery packs due to volume expansion, and such contact rapidly increases the heat transfer rate and accelerates the spread of thermal runaway or fire.

[0010] When a plurality of battery packs are arranged at large intervals, the number of battery packs that can be received in one battery rack is reduced, and the overall energy density of the battery rack is reduced, and thus there is a limitation in spacing the battery packs apart. Summary of the Invention

[0011] Technical issues

[0012] The present disclosure is designed to solve the above-described problems, and thus the present disclosure aims to provide a battery rack for effectively preventing fire or heat from spreading to adjacent battery packs when fire or thermal runaway occurs in any one of a plurality of battery packs.

[0013] These and other purposes and advantages of the present disclosure can be understood through the following description and will be apparent from the embodiments of the present disclosure.In addition, it will be readily understood that the purposes and advantages of the present disclosure can be achieved by the means set forth in the appended claims and their combinations.

[0014] Technical Solution

[0015] In order to achieve the above-mentioned purpose, a battery rack according to the present disclosure includes: a plurality of battery packs; and a battery rack housing, which has a receiving space, and the receiving space has an open structure, in which the plurality of battery packs are vertically installed at intervals and are placed to be vertically connected to each other, wherein a stopper is arranged in the receiving space and is placed between the plurality of battery packs in a manner spaced apart from the plurality of battery packs, and the stopper is constructed so that when the volume of the battery pack expands, the stopper suppresses the volume expansion of the battery pack.

[0016] The battery rack housing includes an upper wall, a lower wall, a left side wall, a right side wall and a rear wall to form the receiving space.

[0017] The stopper may have a beam shape horizontally extending from at least one of the left side wall, the right side wall, or the rear wall.

[0018] The beam shape of the stopper may have a rectangular, I-shaped or H-shaped vertical cross-section.

[0019] The stopper may include a body portion configured to press the battery pack when a volume of the battery pack expands, and a fixing portion coupled to at least one of the rear wall, the left wall, or the right wall.

[0020] The battery rack housing may further include a plurality of rack plates configured to upwardly support a bottom portion of each of the plurality of battery packs.

[0021] The body portion of the stopper may be connected to the frame plate and have a downwardly stepped structure.

[0022] The battery rack housing may further include a base member disposed between a lower surface of the battery pack and a rack plate, the base member being configured to undergo a phase change from solid to liquid at or above a predetermined temperature.

[0023] The battery rack housing may further include a heat shielding pad placed above or below the stopper to block heat conduction.

[0024] The battery rack housing may further include a cooling pad positioned above or below the stopper to absorb heat.

[0025] To achieve the above objectives, an energy storage system according to the present disclosure includes at least one battery rack.

[0026] Beneficial effects

[0027] According to aspects of the present disclosure, the battery rack described in the present disclosure includes: a plurality of battery packs; and a battery rack housing, the battery rack housing having a receiving space, the receiving space having an open structure, in which the plurality of battery packs are vertically installed at intervals and are placed to be vertically connected to each other, wherein a stopper configured to suppress the volume expansion of the battery pack is provided in the receiving space, so that when the size of the battery pack is deformed due to the volume expansion of the plurality of secondary battery cells in the battery pack caused by thermal runaway or fire, the stopper can suppress the deformed battery pack from contacting the battery pack placed above or below, thereby preventing the thermal runaway or fire from spreading to other battery packs due to heat transfer from the battery pack where thermal runaway or fire has occurred to the adjacent battery pack.

[0028] Additionally, according to aspects of an embodiment of the present disclosure, the battery rack of the present disclosure further includes a heat shielding pad placed above or below the stopper to block heat conduction, so that the heat shielding pad can inhibit heat transfer from a battery pack that has thermal runaway or fire to a battery pack placed above or below.

[0029] Additionally, according to another aspect of the present disclosure, the battery rack of the present disclosure further includes a base member that is placed between the lower surface of the battery pack and the rack plate and is configured to change phase from solid to liquid at a predetermined temperature or above, so that when thermal runaway or fire occurs in any of the multiple battery packs, the base member becomes thinner due to the heat generated, so that the battery pack that has experienced thermal runaway or fire moves downward. Accordingly, the battery pack whose volume has expanded due to thermal runaway or fire can be prevented from contacting adjacent battery packs, thereby effectively reducing the amount of heat conduction. Ultimately, when thermal runaway or fire occurs in any battery pack, the thermal runaway or fire can be prevented from spreading to adjacent battery packs. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The accompanying drawings illustrate preferred embodiments of the present disclosure and, together with the following detailed description, serve to provide a further understanding of the technical aspects of the present disclosure. However, the present disclosure should not be construed as being limited to the accompanying drawings.

[0031] Figure 1 is a schematic front perspective view of a battery rack according to an embodiment of the present disclosure.

[0032] Figure 2 is a schematic front perspective view of a battery pack of a battery rack according to an embodiment of the present disclosure.

[0033] Figure 3 is a schematic three-dimensional diagram of a battery cell assembly of a battery pack of a battery rack according to an embodiment of the present disclosure.

[0034] Figure 4 is a schematic front view of a battery rack according to an embodiment of the present disclosure.

[0035] Figure 5 2 is a schematic front view showing the volume expansion of a battery pack of a battery rack according to an embodiment of the present disclosure.

[0036] Figure 6 It is a schematic three-dimensional diagram of a battery rack housing of a battery rack according to an embodiment of the present disclosure.

[0037] Figure 7 It is along Figure 6 A horizontal cross-sectional view taken along line CC' in FIG. 1 shows components of a battery rack.

[0038] Figure 8 is a horizontal cross-sectional view of components of a battery rack according to a second embodiment of the present disclosure.

[0039] Figure 9 is a horizontal cross-sectional view of components of a battery rack according to a third embodiment of the present disclosure.

[0040] Figure 10 4 is a schematic front view of a battery rack according to a fourth embodiment of the present disclosure.

[0041] Figure 11 4 is a schematic front view of a battery rack according to a fifth embodiment of the present disclosure.

[0042] Figure 12 4 is a schematic front view of a battery rack according to a sixth embodiment of the present disclosure.

[0043] Figure 13 is a horizontal cross-sectional view of components of a battery rack according to a sixth embodiment of the present disclosure.

[0044] Figure 14 4 is a schematic front view of a battery rack according to a seventh embodiment of the present disclosure.

[0045] Figure 15 4 is a schematic front view of a battery rack according to an eighth embodiment of the present disclosure.

[0046] Figure 16 4 is a schematic front view of a battery rack according to a ninth embodiment of the present disclosure.

[0047] Figure 17 4 is a schematic front view of a battery rack according to a tenth embodiment of the present disclosure.

[0048] Figure 18 is a temperature variation graph of a battery pack subjected to thermal runaway used in the experiments of the present disclosure.

[0049] Figure 19 FIG. 1 is a temperature change graph of a battery pack of a comparative example used in the experiments of the present disclosure.

[0050] Figure 20 FIG. 4 is a temperature variation graph of an example battery pack used in the experiments of the present disclosure. DETAILED DESCRIPTION

[0051] 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 or words used in the specification and the appended claims should not be understood as limited to the general and dictionary meanings, but should be interpreted based on the meanings and concepts corresponding to the technical aspects of the present disclosure on the basis of the principle that allows the inventor to appropriately define the terms for the best interpretation.

[0052] Therefore, the embodiments described herein and the illustrations shown in the accompanying drawings are merely the most preferred embodiments of the present disclosure, rather than being intended to fully describe the technical aspects of the present disclosure, and thus it should be understood that various other equivalents and modifications may have been made thereto when the application is filed.

[0053] Figure 1 is a schematic front perspective view of a battery rack according to an embodiment of the present disclosure. Figure 2 : is a schematic front perspective view of a battery pack of a battery rack according to an embodiment of the present disclosure. Figure 3 is a schematic perspective view of a battery cell assembly of a battery pack of a battery rack according to an embodiment of the present disclosure. Figure 1 , the X-axis direction refers to the left-right direction, the Y-axis direction refers to the front-back direction, and the Z-axis direction refers to the up-down direction.

[0054] refer to Figures 1 to 3 The battery rack 300 described in the present disclosure includes a plurality of battery packs 200 and a battery rack housing 310 .

[0055] First, the plurality of battery packs 200 may be received in the battery rack housing 310 in a vertical arrangement. Furthermore, the plurality of battery packs 200 may include a pack housing 210, a modular battery management system (BMS) 230, and a battery cell assembly 100 having a plurality of secondary battery cells 110 disposed in the pack housing 210 and stacked in a certain direction. Here, the modular BMS 230 may be configured to measure the current and temperature of the battery pack 200 and control the charge / discharge of the plurality of secondary battery cells 110.

[0056] In addition, the battery pack 200 may include two external I / O terminals 221 at the front end. One of the two external I / O terminals 221 may have a positive polarity, and the other external I / O terminal may have a negative polarity.

[0057] Specifically, the secondary battery cell 110 may be a pouch-type secondary battery cell 110. For example, Figure 3 As shown in , when the direction F( Figure 1 As shown, the battery cell assembly 100 may include 21 pouch-type secondary battery cells 110 stacked side by side in a front-to-rear direction.

[0058] In this specification, unless otherwise specified, the up, down, front, back, left, and right directions are defined when viewed from the direction F.

[0059] like Figure 3As shown in FIG, when viewed from the direction F, the positive electrode lead 112 and the negative electrode lead 111 may be formed at the left and right ends relative to the center of the pouch 116 of the secondary battery cell 110. That is, the positive electrode lead 112 may be disposed at one end (the left end) relative to the center of the secondary battery cell 110. In addition, the negative electrode lead 111 may be disposed at the other end (the right end) relative to the center of the secondary battery cell 110.

[0060] However, the battery pack 200 according to the present disclosure is not limited to the above-described pouch-type secondary battery cell 110 , but may use various types of secondary battery cells 110 known at the time of filing this application.

[0061] In the following description, “horizontal direction” refers to a direction parallel to the ground when the battery pack 200 is placed on the ground, and may be referred to as at least one direction on a plane perpendicular to the vertical direction.

[0062] The battery pack 200 may include at least one bus bar (not shown) configured to electrically connect the plurality of secondary battery cells 110. Specifically, the bus bar may have a conductive metal such as copper, aluminum, and nickel.

[0063] Figure 4 is a schematic front view of a battery rack according to an embodiment of the present disclosure. Figure 5 : is a schematic front view showing the volume expansion of a specific battery pack of the battery rack according to an embodiment of the present disclosure. Figure 6 It is a schematic three-dimensional diagram of a battery rack housing of a battery rack according to an embodiment of the present disclosure.

[0064] and Figure 1 Reference together Figures 4 to 6 The battery rack housing 310 of the present disclosure may include a plurality of battery packs 200 vertically mounted therein at intervals. The battery rack housing 310 may include a receiving space 312 having an open structure to allow the plurality of battery packs 200 to be placed in vertical communication with one another. For example, the battery rack housing 310 may include outer sidewalls defining the receiving space 312. The outer sidewalls may include an upper wall 310a, a lower wall 310b, a left sidewall 310c, a right sidewall 310d, and a rear wall 310e.

[0065] In addition, a plurality of vertically arranged shelf plates 318 may be provided on each of the inner surfaces of the left side wall 310 c and the right side wall 310 d in the receiving space 312 of the battery rack housing 310. The plurality of battery packs 200 may be vertically arranged in the plurality of shelf plates 318 at predetermined intervals. The shelf plates 318 arranged on the left and right sides may have an open structure between them to place the plurality of battery packs 200 in vertical communication with each other. This open structure allows air flowing between the battery packs 200 to move vertically smoothly.

[0066] like Figure 5 As shown in , when the volume of a certain battery pack 200A expands, the receiving space 312 may include at least one stopper 320, and the at least one stopper 320 is configured to suppress the volume expansion of the battery pack 200A. For example, the stopper 320 may be placed between the multiple battery packs 200. The stopper 320 may be spaced apart from the multiple battery packs 200 in the vertical direction (Z-axis direction). For example, among the multiple battery packs 200, the stopper 320 may be placed below the upper battery pack 200 and above the lower battery pack 200.

[0067] In addition, because the battery pack 200 includes a plurality of pouch-type secondary battery cells 110, when abnormal behavior such as thermal runaway or fire occurs in the plurality of pouch-type secondary battery cells 110 during charge / discharge of the battery pack 200, a large amount of gas is generated in the plurality of pouch-type secondary battery cells 110, thereby causing the volume of the pouch-type secondary battery cells 110 to expand. As a result, the shape of the battery pack 200A may expand and deform due to internal pressure. In this case, Figure 5 As shown in FIG, the stopper 320 of the present disclosure may be configured to suppress volume expansion of the battery pack 200 in a downward or upward direction.

[0068] According to the construction described in the present disclosure, the battery rack housing 310 described in the present disclosure includes a plurality of battery packs 200 and a battery rack housing 310 having the receiving space 312, wherein the receiving space 312 has an open structure, and the plurality of battery packs 200 are vertically installed therein at a certain interval and are placed to be vertically connected to each other, wherein the stopper 320 is arranged in the receiving space 312 and is configured to suppress the volume expansion of any battery pack 200A, so that when the size of the battery pack 200 is deformed due to the volume expansion of the plurality of secondary battery cells 110 in the battery pack 200 caused by thermal runaway or fire, the stopper 320 can suppress the deformed battery pack 200A from contacting other battery packs 200 placed above or below, thereby preventing thermal runaway or fire from spreading to other battery packs 200 due to heat transfer from the battery pack 200A that has thermal runaway or fire to the adjacent battery pack 200.

[0069] Figure 7 It is along Figure 6 A horizontal cross-sectional view taken along line CC' in FIG. 1 shows components of a battery rack. Figure 8 : is a horizontal cross-sectional view of a component of a battery rack according to a second embodiment of the present disclosure. Figure 9 is a horizontal cross-sectional view of components of a battery rack according to a third embodiment of the present disclosure.

[0070] Here, for the convenience of describing the drawings, Figures 7 to 9 Only the outer sidewalls of the battery holder housing 310 and the stopper 320 are shown.

[0071] and Figure 4 and Figure 6 Reference together Figure 7 The stopper 320 of the present disclosure may have a beam shape extending horizontally from at least one of the left side wall 310c, the right side wall 310d or the rear wall 310e. Figure 7 As shown in FIG, the stopper 320 may be in the shape of a hexagonal beam extending forward from the inner surface of the rear wall 310e of the battery rack housing 310. Figure 7 One stopper 320 is shown, but at least three stoppers 320 may be horizontally arranged.

[0072] and Figure 4 and Figure 6 Reference together Figure 8 The stopper 320A of the battery rack 300A according to the second embodiment may be in the shape of a beam extending from the inner surface of the left side wall 310c to the inner surface of the right side wall 310d of the battery rack housing 310A. That is, the stopper 320A may have an I-shaped beam shape in a plane. Figure 8 The stopper 320A shown is connected to the inner surface of each of the left side wall 310c and the right side wall 310d of the battery rack housing 310A, and thus is different from the stopper 320A connected only to the rear wall 310e of the battery rack housing 310A. Figure 7 Compared to the stopper 320 shown, a stronger force is applied to suppress the deformation of the battery pack 200 .

[0073] and Figure 4 and Figure 6 Reference together Figure 9 According to the third embodiment, the stopper 320B of the battery rack 300B may have a cross shape including a hexagonal beam extending forward from the inner surface of the rear wall 310e of the battery rack housing 310B and an I-shaped beam extending from the inner surface of the left side wall 310c to the inner surface of the right side wall 310d of the battery rack housing 310B.

[0074] Accordingly, according to the third embodiment of the present disclosure Figure 9 The stopper 320B shown has a cross shape with a hexagonal beam connected to the rear wall 310e and an I-shaped beam connected to the left and right walls 310c and 310d of the battery holder housing 310B, and thus can have more connection portions than the stopper 320A connected to the left and right walls 310c and 310d according to the second embodiment. Figure 8 Compared to the stopper 320A shown, Figure 9 The illustrated stopper 320B may apply a stronger force to suppress the deformed battery pack 200 .

[0075] and Figure 4 and Figure 6 Let’s refer to it again Figure 7 The stopper 320 may include a body portion 321 and a fixing portion 323. The body portion 321 may be configured to press the battery pack 200 when the volume of the battery pack 200 expands. For example, the body portion 321 may be positioned at a position corresponding to the center of the battery pack 200 where deformation is most likely to occur.

[0076] In addition, the fixing portion 323 may be coupled to at least one of the rear wall 310e, the left side wall 310c, or the right side wall 310d. Figure 7 , Figure 7 The stopper 320 shown includes a body portion 321 located at a position corresponding to the central axis of the battery pack 200 in the front-to-back direction, and the fixing portion 323 can be coupled to the inner surface of the rear wall 310e of the battery holder housing 310. In this case, welding or bolting can be used.

[0077] refer to Figure 8 , Figure 8 The stopper 320A shown includes a main body portion 321 located at a position corresponding to the central axis of the battery pack 200 in the left-right direction, and the fixing portion 323 can be formed on each of the inner surfaces of the left side wall 310c and the right side wall 310d of the battery holder housing 310.

[0078] refer to Figure 9 , Figure 9 The stopper 320B shown includes a main body portion 321 located at a position corresponding to the central axis in the front-to-back direction and the central axis in the left-to-right direction of the battery pack 200, and the fixing portion 323 can be connected to each of the inner surface of the rear wall 310e, the inner surface of the left side wall 310c and the inner surface of the right side wall 310d of the battery holder housing 310.

[0079] Figure 10 4 is a schematic front view of a battery rack according to a fourth embodiment of the present disclosure.

[0080] refer to Figure 10 The battery rack housing 310C of the battery rack 300C according to the fourth embodiment may further include a heat shielding pad 350. The heat shielding pad 350 may be placed above or below the stopper 320. For example, the heat shielding pad 350 may be attached to the upper or lower surface of the stopper 320 using an adhesive (not shown). The heat shielding pad 350 may include a heat shielding material, for example: a heat-resistant resin such as polyimide; a fibrous material such as glass wool or mineral wool; and / or a ceramic material.

[0081] According to this construction described in the present disclosure, the battery rack housing 310C described in the present disclosure further includes a heat shielding pad 350 placed above or below the stopper 320 to block heat conduction, so that the heat shielding pad 350 can inhibit heat transfer from the battery pack 200 that has thermal runaway or fire to other battery packs 200 placed above or below.

[0082] Figure 11 4 is a schematic front view of a battery rack according to a fifth embodiment of the present disclosure.

[0083] refer to Figure 11The battery rack housing 310D of the battery rack 300D according to the fifth embodiment of the present disclosure may further include a cooling pad 360, which is located above or below the stopper 320. The cooling pad 360 may be configured to absorb heat. For example, the cooling pad 360 may include a refrigerant (not shown) that evaporates when it absorbs heat. For example, the refrigerant may be water, a Freon-type refrigerant, ammonia, acetone, methanol, ethanol, naphthalene, sulfur, or mercury.

[0084] According to the construction described in the present disclosure, the battery rack housing 310D described in the present disclosure further includes a cooling pad 360 placed above or below the stopper 320 and configured to absorb heat, so that the cooling pad 360 absorbs heat generated from the battery pack 200 that has thermal runaway or fire, thereby suppressing heat transfer to other battery packs 200 placed above or below.

[0085] Figure 12 4 is a schematic front view of a battery rack according to a sixth embodiment of the present disclosure. Figure 13 : is a horizontal cross-sectional view of a component of a battery rack according to a sixth embodiment of the present disclosure. Here, for the convenience of describing the drawings, Figure 13 Portions of the outer side walls of the battery rack, the rack plates, and the stops are shown.

[0086] refer to Figure 12 and Figure 13 The battery rack housing 310E of the battery rack 300E according to the sixth embodiment of the present disclosure includes a plurality of rack plates 318. Each of the plurality of rack plates 318 may be configured to upwardly support the bottom of each of the plurality of battery packs 200. For example, Figure 12 As shown in FIG, a pair of shelf plates 318 may be coupled to the inner surfaces of the left side wall 310c and the right side wall 310d of the battery rack housing 310E, respectively. In this case, both lower ends of a battery pack 200 may be mounted on the pair of shelf plates 318, respectively. The battery rack housing 310E may include a total of ten shelf plates 318, thereby mounting five battery packs 200 at predetermined intervals.

[0087] In addition, if Figure 13 As shown in FIG, the stopper 320E of the battery rack housing 310E according to the sixth embodiment of the present disclosure may include a body portion 321E connected to the rack plate 318. The stopper 320E may have a stepped structure 320s that is stepped downward from the rack plate 318 at a predetermined distance from the battery pack 200 mounted on the rack plate 318. For example, Figure 12As shown in FIG, the stopper 320E may have a stepped structure 320s that is stepped downward on the left and right sides relative to the center of the body portion 321E.

[0088] According to the construction described in the present disclosure, the present disclosure includes a main body portion 321E of the stopper 320E connected to the rack plate 318 and a step structure 320s that is stepped downward, so that the stopper 320E can elastically suppress the expansion of the battery pack 200 through the step structure 320s and apply a stronger downward force.

[0089] Figure 14 4 is a schematic front view of a battery rack according to a seventh embodiment of the present disclosure.

[0090] refer to Figure 14 The battery rack housing 310F of the battery rack 300F according to the seventh embodiment may further include a base member 340 having a predetermined vertical thickness. The base member 340 may be placed between the lower surface of the battery pack 200 and the rack plate 318. For example, Figure 14 As shown in FIG, two base members 340 may be placed on the upper surfaces of two rack plates 318 arranged on the left and right sides. The battery pack 200 may be mounted on the upper surfaces of the two base members 340.

[0091] In addition, the base member 340 may be configured to undergo a phase change from a solid to a liquid at or above a predetermined temperature. For example, a representative example of the phase change material of the base member 340 may be paraffin wax, which is inexpensive and has a readily adjustable phase change temperature depending on the molecular weight. However, the phase change material is not necessarily limited thereto. Paraffin wax may be configured to undergo a phase change at 90°C to 200°C (e.g., Paraffin 163, USA).

[0092] When thermal runaway or fire occurs in the battery pack 200, the base member 340 absorbs the generated heat, allowing the base member 340 to undergo a phase change. When the phase changes from solid to liquid, the phase-changed portion of the base member 340 may leak out from the space between the frame plate 318 and the battery pack 200. Accordingly, as the phase amount increases, the base member 340 can become thinner. In addition, as the vertical thickness of the base member 340 decreases, the position of the battery pack 200 can be gradually lowered. That is, the base member 340 is melted by the heat generated by the battery pack 200, and accordingly, the position of the battery pack 200 is lowered, thereby reducing the upward movement of the top of the battery pack 200 due to the volume expansion of the battery pack 200.

[0093] According to this configuration described in the present disclosure, a battery rack housing 310F according to another embodiment of the present disclosure further includes a base member 340. The base member 340 is positioned between the lower surface of the battery pack 200 and the rack plate 218 and is configured to undergo a phase change from solid to liquid at a predetermined temperature or above. Therefore, when thermal runaway or fire occurs in any of the multiple battery packs 200, the base member becomes thinner due to the generated heat, causing the position of the battery pack 200 experiencing thermal runaway or fire to move downward. Accordingly, a battery pack 200 whose volume has expanded due to thermal runaway or fire can be prevented from contacting an adjacent battery pack 200, thereby effectively reducing the amount of heat conduction. Ultimately, when thermal runaway or fire occurs in any battery pack 200, the thermal runaway or fire can be prevented from spreading to an adjacent battery pack 200.

[0094] Figure 15 4 is a schematic front view of a battery rack according to an eighth embodiment of the present disclosure.

[0095] refer to Figure 15 , Figure 15 The stopper 320G of the illustrated battery rack 300G may be in the shape of a beam having a rectangular vertical cross-section, that is, the stopper 320G may have a hollow tubular shape.

[0096] Accordingly, according to the present disclosure Figure 15 The stopper 320G shown is in the shape of a beam with a rectangular vertical cross-section, so that when contacting the battery pack, the volume expansion of the battery pack can be suppressed by the top or bottom of the stopper 320G, and an air gap can be formed through the hollow internal space, thereby effectively reducing heat transfer to adjacent battery packs.

[0097] Figure 16 4 is a schematic front view of a battery rack according to a ninth embodiment of the present disclosure.

[0098] refer to Figure 16 The stopper 320H of the battery rack 300H according to the ninth embodiment can be in the shape of a beam having an H-shaped vertical cross-section. Specifically, the stopper 320H can be in the shape of an H-shaped steel bar. Specifically, the stopper 320H can include a vertically extending left plate 320H1, a horizontal plate 320H2 extending horizontally from the left plate 320H1 and parallel to the ground, and a right plate 320H3 extending vertically from the right end of the horizontal plate 320H2.

[0099] Accordingly, according to the present disclosure Figure 16The stopper 320H shown is in the shape of a beam with an H-shaped vertical cross-section, so that when contacting the battery pack 200, the volume expansion of the battery pack 200 can be suppressed by the top or bottom of the left plate 320H1 and the right plate 320H3 of the stopper 320H, and an air gap can be formed through the hollow space between the left plate 320H1 and the right plate 320H3, thereby effectively reducing heat transfer to the adjacent battery pack 200.

[0100] Figure 17 4 is a schematic front view of a battery rack according to a tenth embodiment of the present disclosure.

[0101] refer to Figure 17 , Figure 17 The stopper 320I of the illustrated battery rack 300I may be in the shape of a beam having an I-shaped vertical cross-section. Specifically, the stopper 320I may include a horizontally extending upper plate 320I1, a middle plate 320I2 extending downward from the upper plate 320I1 and standing perpendicular to the ground, and a lower plate 320I3 extending horizontally from the lower end of the middle plate 320I2.

[0102] Accordingly, according to the present disclosure Figure 17 The stopper 320I of the battery rack 300I shown is in the shape of a beam with an I-shaped vertical cross-section, so that when contacting the battery pack 200, the volume expansion of the battery pack 200 can be suppressed by the top of the upper plate 320I1 or the bottom of the lower plate 320I3 of the stopper 320I, and an air gap can be formed through the hollow space between the upper plate 320I1 and the lower plate 320I3, thereby effectively reducing heat transfer to the adjacent battery pack 200.

[0103] Come back for reference Figure 1 The battery rack 300 may include a battery rack BMS located on top of the plurality of battery packs 200. Here, the battery rack BMS may be a battery management system for central control of charge / discharge of the plurality of battery packs 200 provided in the battery rack 300.

[0104] An electronic storage system (not shown) according to the present disclosure may include at least one battery rack 300 according to the present disclosure. Specifically, the electronic storage system may include multiple battery racks 300 according to the present disclosure. The multiple battery racks 300 may be electrically connected to each other via battery rack bus bars (not shown). The electronic storage system according to the present disclosure may be implemented in various forms, such as a smart grid system or a charging station.

[0105] Hereinafter, the present disclosure is described in more detail by specifically describing comparative examples and examples, but the present disclosure is not limited to the comparative examples and examples. The examples / embodiments of the present disclosure can be modified into many other forms, and the scope of the present disclosure should not be interpreted as being limited to the following examples / embodiments. The examples / embodiments of the present disclosure are provided to help those skilled in the art fully and completely understand the present disclosure.

[0106] <Comparative Example>

[0107] A battery rack according to a comparative example of the present disclosure includes two battery packs vertically arranged at a distance from each other, and a battery rack housing. In this case, a heat shield member having a vertical thickness of 6 mm is placed on the lower surface of the upper battery pack in each of the two battery packs.

[0108] Subsequently, thermal runaway was intentionally induced by an electrical short circuit in the secondary battery cells embedded in the battery pack located at the lower position. Due to the volume expansion of the secondary battery cells that underwent thermal runaway, the battery pack bulged and its volume expanded, and the upper surface of the expanded battery pack came into close contact with the heat shield member placed on the lower surface of the upper battery pack. In the comparative example, after inducing an electrical short circuit in the secondary battery cells of the lower battery pack, the temperature of each of the two battery packs was measured for a total of 150 minutes, and the experimental results were Figure 18 and Figure 19 In this case, Figure 18 is a graph showing temperature changes of a battery pack that has experienced thermal runaway. Figure 19 is a graph showing temperature changes of the upper battery pack.

[0109] <Example>

[0110] In the examples described herein, a battery rack was prepared in the same manner as in the comparative example. The battery rack included two battery packs vertically arranged at a distance from each other, and a battery rack housing. In this case, a heat shield member having a vertical thickness of 6 mm was placed on the lower surface of the upper battery pack of the two battery packs.

[0111] However, in contrast to the comparative example, in the example described in the present disclosure, the battery rack housing further includes a stopper. The stopper has a plate shape elongated in the front-to-back direction and is placed between the two battery packs so that the volume of the lower battery pack is as large as Figure 5 and 6 In this case, the distance from the lower surface of the stopper to the lower surface of the heat shield member is set to 2.8 mm.

[0112] Subsequently, of the two battery packs, thermal runaway was intentionally induced in the lower battery pack. In contrast to the comparative example, Figure 5 As shown in , the volume of the lower battery pack that has thermal runaway has expanded, but the volume expansion of the battery pack is suppressed by a stopper provided in the battery rack housing.

[0113] Because the battery rack according to the example of the present disclosure suppresses the volume expansion of the lower battery pack by the stopper, the lower battery pack can be kept 2.8 mm apart from the heat shield member. After inducing an electrical short circuit in the secondary battery cells of the lower battery pack, the temperature of the battery pack of the example was measured for a total of 150 minutes. The lower battery pack that experienced thermal runaway showed a temperature similar to Figure 18 The temperature change of the graph showing the temperature change. The temperature change of the upper battery pack is Figure 20 Shown in.

[0114] As a result of the experiment, in the comparative example, Figure 18 As shown in , the temperature of the battery pack that suffered thermal runaway rapidly increased from about 40 minutes and reached about 900°C. Figure 19 As shown in Figure 3, starting from approximately 40 minutes, the temperature of the battery pack gradually increases due to the heat generated by the battery pack experiencing thermal runaway being transferred to the upper battery pack. Subsequently, starting from approximately 120 minutes, it can be seen that the temperature rises to over 900°C due to thermal runaway occurring in the secondary battery cells of the upper battery pack.

[0115] In contrast, in the example, Figure 20 As shown in , it can be seen that some heat is transferred from the battery pack in thermal runaway to the upper battery pack, and the temperature gradually increases from about 60 minutes and exceeds 100°C at about 150 minutes. That is, in contrast to the battery rack of the comparative example, the upper battery pack of the battery rack described in the example does not have a rapid temperature rise. This is because the battery rack described in the example of the present disclosure has a 2.8 mm thick air gap between the two battery packs through the stopper, and a heat shielding effect is applied through the air gap, thereby preventing the temperature from rising enough to cause thermal runaway in the upper battery pack. Accordingly, the battery rack described in the present disclosure includes a stopper provided in the battery rack housing, thereby effectively preventing the propagation of thermal runaway between multiple battery packs.

[0116] Terms indicating directions such as up, down, left, right, front, and rear used herein are only used for convenience of description, and it is obvious to those skilled in the art that these terms may change depending on the elements being described or the position of an observer.

[0117] While the present disclosure has been described above with respect to a limited number of embodiments and drawings, it is not limited thereto, and it will be apparent to those skilled in the art that various modifications and changes may be made thereto within the technical aspects of the present disclosure and the equivalent scope of the appended claims.

[0118] Description of Reference Numerals

[0119] 300: Battery rack

[0120] 200: Battery pack 100: Battery cell assembly

[0121] 110: Secondary battery cell 210: Battery pack cover

[0122] 310: Battery rack housing 312: Receiving space

[0123] 320: Stopper 321, 323: Main body, fixing part

[0124] 310a, 310b, 310c, 310d, 310e: upper wall, lower wall, left wall, right wall, and back wall

[0125] 350: Heat shield pad 360: Cooling pad

[0126] 318: Shelf 230: Module BMS

[0127] 320s: Step structure

[0128] 340: Base member 221: External I / O terminal

Claims

1. A battery rack, comprising: Multiple battery packs; and a battery rack housing having a receiving space having an open structure, in which the plurality of battery packs are vertically installed at intervals and are placed to be vertically communicated with each other, wherein the stopper is provided in the receiving space and is placed between the plurality of battery packs in a manner spaced apart from the plurality of battery packs, and the stopper is configured to suppress the volume expansion of the battery pack when the volume of the battery pack expands. The battery rack housing includes an upper wall, a lower wall, a left wall, a right wall and a rear wall to form the receiving space. In which, the stop member has a hexagonal beam connected to the rear wall of the battery rack housing and extending forward from the inner surface of the rear wall of the battery rack housing, and an I-shaped beam connected to the left and right walls of the battery rack housing and extending from the inner surface of the left wall to the inner surface of the right wall.

2. The battery rack according to claim 1, wherein: The stopper extends horizontally.

3. The battery rack according to claim 1 or 2, wherein: The stopper comprises: a body portion configured to squeeze the battery pack when the volume of the battery pack expands; and A fixing portion is coupled to the rear wall, the left side wall, and the right side wall.

4. The battery rack according to claim 3, wherein: The battery rack housing further includes a plurality of rack plates configured to upwardly support a bottom portion of each of the plurality of battery packs.

5. The battery rack according to claim 4, wherein: The body portion of the stopper is connected to the frame plate and has a downwardly stepped structure.

6. The battery rack according to claim 5, wherein: The battery rack housing further includes a base member disposed between a lower surface of the battery pack and the rack plate, and configured to undergo a phase change from solid to liquid at or above a predetermined temperature.

7. The battery rack according to claim 1, wherein: The battery rack housing further includes a heat shielding pad, which is placed above or below the stopper to block heat conduction.

8. The battery rack according to claim 1, wherein: The battery rack housing further includes a cooling pad placed above or below the stopper to absorb heat.

9. An energy storage system comprising at least one battery rack according to any one of claims 1 to 8.

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