Battery pack and power storage device including battery pack

Abstract

The battery pack according to the present invention includes a pack case, a cell module provided inside the pack case and including a cell assembly having a plurality of battery cells, a fire tank arranged above the cell assembly and holding a fire extinguishing agent in its internal space, and an end plate arranged on at least one of the front and rear sides of the cell assembly and configured to support the fire tank.

Description

[Technical field]

[0001] (CROSS REFERENCE TO RELATED APPLICATIONS) This application claims the benefit of priority based on Korean Patent Application No. 10-2022-0030830 dated March 11, 2022, and all contents disclosed in the documents of said Korean patent application are incorporated herein by reference.

[0002] (Technical field) The present invention relates to a battery pack and a power storage device including a battery pack, and more particularly to a battery pack configured to ensure safety even in the event of a thermal event and a power storage device including such a battery pack. [Background technology]

[0003] Recently, as the demand for portable electronic products such as laptops, video cameras, and mobile phones has increased dramatically and the development of electric vehicles, energy storage batteries, robots, satellites, and the like has progressed in earnest, research into high-performance secondary batteries that can be repeatedly charged and discharged has been actively conducted.

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

[0005] Such a lithium secondary battery mainly uses a lithium-based oxide and a carbon material as a positive electrode active material and a negative electrode active material, respectively, and includes a positive electrode plate and a negative electrode plate coated with the positive electrode active material and the negative electrode active material, an electrode assembly in which the positive electrode plate and the negative electrode plate are arranged with a separator sandwiched therebetween, and an exterior material that hermetically houses the electrode assembly together with an electrolyte.

[0006] On the other hand, lithium secondary batteries are classified into can-type secondary batteries, in which the electrode assembly is housed in a metal can, and pouch-type secondary batteries, in which the electrode assembly is housed in a pouch made of an aluminum laminate sheet, according to the shape of the battery case. Can-type secondary batteries are further classified into cylindrical batteries and prismatic batteries, according to the shape of the metal can.

[0007] Here, the pouch of the pouch-type secondary battery is roughly divided into a lower sheet and an upper sheet that covers the lower sheet. At this time, an electrode assembly formed by stacking and winding a positive electrode, a negative electrode, and a separator is housed in the pouch. After the electrode assembly is housed, the periphery of the upper sheet and the lower sheet is sealed by heat sealing or the like. In addition, the electrode tabs drawn out from each electrode are connected to electrode leads, and an insulating film is added to the electrode leads at the portions in contact with the sealing portions.

[0008] As described above, the pouch-type secondary battery has the versatility to be configured in various shapes, and has the advantage that a secondary battery of the same capacity can be realized with a smaller volume and mass.

[0009] The application of such lithium secondary batteries is gradually increasing, for example to energy storage devices (ESS: Energy Storage Systems). The lithium secondary batteries are used as cell modules or battery packs in which several battery cells are stacked or laminated on their own or in a cartridge or the like to provide high voltage and high current, and then electrically connected to each other. As an example, the power storage device may be a collection of residential battery packs used in various types of housing (e.g., detached houses, apartments, etc.).

[0010] In such a battery pack configuration, one of the most important issues is safety. In particular, when a thermal event occurs in one of the battery cells included in the battery pack, the propagation of such an event to other battery cells must be suppressed. If the thermal propagation between the battery cells is not properly suppressed, this may cause a thermal event in some of the battery cells included in the battery pack, resulting in a larger problem such as a fire or explosion of the battery pack. Furthermore, a fire or explosion occurring in the battery pack may cause significant damage to the lives and property of the surrounding people. In particular, in the case of a battery pack for a home, if a fire or explosion occurs, it may threaten the safety of the people living in the home and may spread to a fire in the home, causing even greater damage. Therefore, in the case of such a battery pack, a configuration capable of appropriately controlling the above-mentioned thermal event is required.

[0011] In particular, in the case of such a battery pack, it is required that the configuration for controlling the above-mentioned thermal events be stably fixed within the battery pack so that the above-mentioned thermal events can be controlled more stably. Summary of the Invention [Problem to be solved by the invention]

[0012] The present invention has been made to solve the above problems, and aims to provide a battery pack and a power storage device including such a battery pack, which have an improved structure so as to appropriately control thermal events that occur inside the battery pack.

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

[0014] In order to achieve the above-mentioned object, a battery pack according to one embodiment of the present invention includes a pack case, a cell module provided inside the pack case and including a cell assembly having a plurality of battery cells, a fire tank arranged above the cell assembly and holding a fire extinguishing agent in its internal space, and an end plate arranged on at least one of the front and rear sides of the cell assembly and configured to support the fire tank.

[0015] Preferably, the end plates are arranged on both the front and rear sides of the cell assembly and are configured to apply pressure to at least one of the front and rear faces of the cell assembly when swelling of the battery cell occurs.

[0016] Preferably, the fire extinguishing tank is configured to discharge extinguishing agent from between both sides of the bottom toward the cell assembly when heat is applied from the cell assembly, and the end plates can support both sides of the bottom of the fire extinguishing tank in the vertical direction.

[0017] Preferably, a fixing portion having a predetermined area and in surface contact with both sides of the bottom of the fire extinguishing tank is provided on the upper side of the end plate.

[0018] Preferably, the fixing portion is bent from an upper end of the end plate and extends a predetermined length along an outer side of the cell assembly.

[0019] Preferably, the end plate may include a first plate arranged on the front side of the cell assembly and supporting the front side of the fire tank in the vertical direction, and a second plate arranged on the rear side of the cell assembly and supporting the rear side of the fire tank in the vertical direction.

[0020] Preferably, the fixing portion may include a first fixing portion formed to extend from an upper end of the first plate in a front-rear direction of the cell assembly and coupled to a front side of the fire tank in a vertical direction.

[0021] Preferably, the first fixing portion is capable of surface contact with the front side of the fire tank.

[0022] Preferably, the fixing portion may further include a second fixing portion formed to extend from an upper end of the second plate in a front-rear direction of the cell assembly and coupled to a rear side of the fire tank in a vertical direction.

[0023] Preferably, the second fixing portion is capable of surface contact with the rear side of the fire tank.

[0024] Preferably, the pack case may include guide protrusions formed to protrude in the vertical direction from a bottom of the pack case and spaced a predetermined distance from the front and rear surfaces of the cell assembly in the front-to-rear direction of the cell assembly.

[0025] Preferably, the guide protrusions are located on opposite sides of the cell assembly across the end plate.

[0026] Preferably, the guide protrusion may include a first protrusion formed at a predetermined distance from the front surface of the cell assembly in the fore-and-aft direction of the cell assembly, and a second protrusion formed at a predetermined distance from the rear surface of the cell assembly in the fore-and-aft direction of the cell assembly.

[0027] Preferably, the first plate is disposed between the first protrusion and the front surface of the cell assembly in the front-rear direction of the cell assembly and configured to apply pressure to the front surface of the cell assembly when swelling of the battery cell occurs.

[0028] Preferably, the second plate is disposed between the second protrusion and the rear surface of the cell assembly in the front-to-rear direction of the cell assembly, and is configured to apply pressure to the rear surface of the cell assembly when swelling of the battery cell occurs.

[0029] Preferably, the battery pack may further include a connecting portion that connects the first plate and the second plate in the front-rear direction of the cell assembly.

[0030] Preferably, the connecting portion may include a first connecting member that connects an upper end of the first plate and an upper end of the second plate in the fore-and-aft direction of the cell assembly and is arranged in multiple numbers along the left-right direction of the cell assembly, and a second connecting member that connects a lower end of the first plate and a lower end of the second plate in the fore-and-aft direction of the cell assembly and is arranged in multiple numbers along the left-right direction of the cell assembly.

[0031] Furthermore, a power storage device according to an embodiment of the present invention includes at least one battery pack according to an embodiment of the present invention as described above. Effect of the Invention

[0032] According to an embodiment of the present invention, the fire extinguishing tank can be more stably fixed in the pack case via the end plate, thereby quickly controlling thermal events inside the pack case and effectively preventing the swelling phenomenon of the cell module at the same time.

[0033] In addition, since the battery pack according to the embodiment of the present invention does not require an additional structure for supporting the fire tank apart from the structure for preventing swelling, it is possible to improve the efficiency of the manufacturing process while ensuring cost competitiveness and realizing a compact structure with higher energy efficiency.

[0034] In addition, various other additional effects can be achieved by various embodiments of the present invention. Such various effects of the present invention will be described in detail in each embodiment, and the description of effects that can be easily understood by a person skilled in the art will be omitted. [Brief description of the drawings]

[0035] The following drawings attached to this specification illustrate preferred embodiments of the present invention and, together with the detailed description of the invention described below, serve to further understand the technical ideas of the present invention. Therefore, the present invention should not be interpreted as being limited only to the matters depicted in such drawings.

[0036] [Figure 1] FIG. 2 is a diagram showing the overall shape of a battery pack according to one embodiment of the present invention.

[0037] [Diagram 2] FIG. 2 is a front view of the battery pack of FIG.

[0038] [Diagram 3] FIG. 2 is a diagram showing the battery pack of FIG. 1 from above.

[0039] [Figure 4] 2 is a diagram showing a detailed structure of the battery pack shown in FIG. 1.

[0040] [Diagram 5] 2 is a diagram showing the overall shape of an end plate provided in the battery pack of FIG. 1.

[0041] [Figure 6] FIG. 6 is a front view of the end plate of FIG. 5.

[0042] [Figure 7] FIG. 6 is a top view of the end plate of FIG. 5.

[0043] [Figure 8] FIG. 6 is a side view of the end plate of FIG. 5.

[0044] [Figure 9] 2 is a side view showing the inside of the battery pack in FIG. 1 in a projected manner. FIG.

[0045] [Figure 10] 2 is a projection view of the inside of the battery pack in FIG. 1 from above. FIG.

[0046] [Figure 11] FIG. 13 shows an end plate according to another embodiment of the present invention.

[0047] [Figure 12] FIG. 13 shows an end plate according to yet another embodiment of the present invention.

[0048] [Figure 13] 13 is a side view showing the inside of a battery pack to which the end plate of FIG. 12 is applied. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0049] Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the attached drawings. Prior to this, the terms and words used in the specification and claims should not be interpreted limitedly to their ordinary or dictionary meanings, but should be interpreted in the meaning and concept consistent with the technical idea of ​​the present invention, in accordance with the principle that the inventor can appropriately define the concept of the term in order to best describe his / her invention.

[0050] Therefore, it should be understood that the embodiments described in this specification and the configurations shown in the drawings are merely the most preferred embodiment of the present invention and do not fully represent the technical ideas of the present invention, and that there may be various equivalents and modifications that can replace them at the time of this application.

[0051] Fig. 1 is a diagram showing the overall shape of a battery pack 10 according to an embodiment of the present invention, Fig. 2 is a diagram showing the battery pack 10 of Fig. 1 from the front, Fig. 3 is a diagram showing the battery pack 10 of Fig. 1 from above, and Fig. 4 is a diagram showing a detailed structure of the battery pack 10 of Fig. 1. At this time, illustration of a second cover 120 described later in Fig. 4 is omitted.

[0052] In an embodiment of the present invention, the X-axis direction shown in the drawings may refer to the front-back direction, the Y-axis direction may refer to the left-right direction perpendicular to the X-axis direction on a horizontal plane (XY plane), and the Z-axis direction may refer to the up-down direction perpendicular to both the X-axis and Y-axis directions.

[0053] 1 to 4, a battery pack 10 according to an embodiment of the present invention may include a pack case 100, a cell module 200, a fire tank 300, and an end plate 400.

[0054] The pack case 100 can accommodate the cell module 200 therein. To this end, the pack case 100 is provided with an accommodation space for accommodating the cell module 200. Such a pack case 100 will be described in more detail in the following related description.

[0055] The cell module 200 is provided inside the pack case 100 and can include a cell assembly 210 .

[0056] The cell assembly 210 may include one or more battery cells. Here, each battery cell may refer to a secondary battery. The battery cells may be provided as pouch-type battery cells, cylindrical battery cells, or prismatic battery cells. As an example, the battery cells may be pouch-type battery cells.

[0057] The battery cells can be arranged to be stacked in one direction and electrically connected to each other. Each battery cell can include a pair of electrode leads 212. In this case, the pair of electrode leads 212 of the plurality of battery cells is formed on both sides of the cell assembly 210 in the left and right direction.

[0058] The fire extinguishing tank 300 is disposed on the upper side of the cell assembly 210 and can hold a fire extinguishing agent therein. Such a fire extinguishing tank 300 has an internal space and can hold a fire extinguishing agent in such internal space. As an example, the fire extinguishing agent may be a liquid such as water, salt water, or antifreeze. The fire extinguishing tank 300 is accommodated inside the pack case 100.

[0059] The fire extinguishing tank 300 is configured in a box shape with an open top, and can provide a space capable of containing a fire extinguishing agent.

[0060] According to the embodiment of the present invention, the extinguishing agent is discharged from the fire tank 300 disposed on the upper part of the cell assembly 210, so that the thermal event of the cell assembly 210 can be more easily controlled. In particular, the extinguishing agent discharged from the fire tank 300 can easily move downward by gravity. Therefore, the heat and fire of the cell assembly 210 can be more easily suppressed by the extinguishing agent.

[0061] The end plate 400 is disposed on at least one of the front and rear sides of the cell assembly 210. The end plate 400 is configured to support the fire extinguishing tank 300.

[0062] Such end plate 400 allows the fire tank 300 to be stably fixed in the pack case 100. As a result, the extinguishing agent is stably discharged from the fire tank 300 to the cell assembly 210 side, and the heat and fire of the cell assembly 210 can be easily suppressed.

[0063] At this time, the end plates 400 may be disposed only on the front and rear sides of the cell assembly 210. Alternatively, the end plates 400 may be disposed on the front and rear sides of the cell assembly 210, respectively.

[0064] In this embodiment, a case where a pair of end plates 400 are provided will be described as an example.

[0065] The end plate 400 is disposed between the pack case 100 and the cell assembly 210 in the front-to-rear direction of the cell assembly 210 and is configured to apply pressure to at least one of the front and rear surfaces of the cell assembly 210 when swelling of the battery cell occurs.

[0066] That is, the end plates 400 are disposed on both the front and rear sides of the cell assembly 210 and are configured to apply pressure to at least one of the front and rear sides of the cell assembly 210 when swelling of the battery cell occurs.

[0067] By applying pressure to the end plates 400 in this manner, the swelling phenomenon that may occur in the cell modules 200 inside the pack case 100 can be effectively suppressed.

[0068] As a result, the end plate 400 prevents swelling that may occur in the cell module 200, and at the same time, the fire tank 300 can be stably fixed within the pack case 100. That is, in this embodiment, the end plate 400 supports both the fire tank 300 and the cell module 200, and therefore no additional fastening parts or fastening structures are required to fix or support these members. As a result, in this embodiment, the end plate 400 can increase the efficiency of the assembly process of the battery pack 10, ensure cost competitiveness, and provide a battery pack 10 with a compact structure having higher energy efficiency.

[0069] The fire tank 300 is configured to discharge extinguishing agent from between both sides of the bottom toward the cell assembly 100 when heat is applied from the cell assembly 100. Here, the end plate 400 can support both sides of the bottom of the fire tank 300 in the vertical direction.

[0070] By supporting both sides of the bottom of the fire extinguishing tank 300 with such end plates 400, the fire extinguishing tank 300 can be supported more stably even when the fire extinguishing agent is being discharged from the fire extinguishing tank 300, and the leakage of the fire extinguishing agent to the outside of the bottom of the fire extinguishing tank 300 can be effectively prevented, thereby improving the efficiency of feeding the fire extinguishing agent to the cell assembly 100 side.

[0071] On the other hand, on the upper side of the end plate 400, fixing portions 412, 422 having a predetermined area and in surface contact with both sides of the bottom of the fire extinguishing tank 300 are provided.

[0072] Such fixing portions 412, 422 enable the fire tank 300 to be supported more stably.

[0073] The fixing parts 412 and 422 are bent from the upper end of the end plate 400 and extend a predetermined length along the outer side of the cell assembly, that is, the end plate 400 has a substantially L-shaped structure.

[0074] According to this embodiment of the present invention, the contact area between both sides of the bottom of the fire tank 300 and the end plates 400 is increased, so that the fire tank 300 is supported more stably.

[0075] Such an end plate 400 will be described in more detail below.

[0076] 5 is a diagram showing the overall shape of end plate 400 provided in battery pack 10 of FIG. 1, FIG. 6 is a diagram showing end plate 400 of FIG. 5 from the front, FIG. 7 is a diagram showing end plate 400 of FIG. 5 from above, FIG. 8 is a diagram showing end plate 400 of FIG. 5 from the side, and FIG. 9 is a diagram showing a projected side view of the interior of battery pack 10 of FIG. 1.

[0077] 4 to 9, the end plate 400 may include a first plate 410 and a second plate 420.

[0078] The first plate 410 is disposed on the front side of the cell assembly 210 and is capable of supporting the front side of the fire tank 300 in the vertical direction.

[0079] Meanwhile, the above-mentioned fixing portions 412 and 422 may include a first fixing portion 412. And, the first plate 410 may include the first fixing portion 412.

[0080] The first fixing part 412 is formed to extend from an upper end of the first plate 410 in the front-rear direction of the cell assembly 210. The first fixing part 412 is coupled to the front side of the fire tank 300 in the up-down direction. The first fixing part 412 can be in surface contact with the front side of the fire tank 300. The first fixing part 412 increases the contact area between the front side of the fire tank 300 and the first plate 410, thereby stably supporting the fire tank 300.

[0081] At this time, the first fixing portion 412 and the fire tank 300 are connected to each other by a separate fastening member (not shown). Alternatively, the first fixing portion 412 and the fire tank 300 may be connected to each other by a separate adhesive member (not shown).

[0082] The second plate 420 is disposed on the rear surface of the cell assembly 210 and is capable of supporting the rear side of the fire tank 300 in the vertical direction.

[0083] Meanwhile, the above-mentioned fixing portions 412 and 422 may further include a second fixing portion 422. And, the second plate 420 may include the second fixing portion 422.

[0084] The second fixing part 422 is formed to extend from an upper end of the second plate 420 in the front-rear direction of the cell assembly 210. The second fixing part 422 is coupled to the rear side of the fire tank 300 in the up-down direction. The second fixing part 422 can be in surface contact with the rear side of the fire tank 300. The second fixing part 422 increases the contact area between the rear side of the fire tank 300 and the second plate 420, thereby stably supporting the fire tank 300.

[0085] At this time, the second fixing portion 422 and the fire tank 300 are connected to each other by a separate fastening member (not shown). Alternatively, the second fixing portion 422 and the fire tank 300 may be connected to each other by a separate adhesive member (not shown).

[0086] The above-described configuration of the end plate 400 allows the fire tank 300 to be stably fixed inside the pack case 100. As a result, the extinguishing agent is stably discharged from the fire tank 300 to the cell assembly 210 side, making it easier to suppress heat and fire in the cell assembly 210.

[0087] Fig. 10 is a projected view from above showing the inside of the battery pack 10 in Fig. 1. At this time, the fire extinguishing tank 300 described above in Fig. 10 is omitted.

[0088] 4 to 10, the above-described pack case 100 may further include a guide protrusion 150. As shown in FIG.

[0089] The guide protrusions 150 are formed to protrude in the up-down direction from the bottom of the pack case 100, and are provided at predetermined intervals from the front and rear surfaces of the cell assembly 210 in the front-rear direction of the cell assembly 210. Here, the guide protrusions 150 may be provided integrally with the bottom of the pack case 100, or may be attached as a separate member.

[0090] Such a guide protrusion 150 is disposed on the opposite side of the cell assembly 210 with the end plate 400 interposed therebetween.

[0091] In particular, such a guide protrusion 150 may include a first protrusion 152 and a second protrusion 154 .

[0092] The first protrusion 152 is formed at a predetermined distance from the front surface of the cell assembly 210 in the front-rear direction of the cell assembly 210 .

[0093] At this time, the first plate 410 is disposed between the first protrusion 152 and the front surface of the cell assembly 210 in the front-rear direction of the cell assembly 210 and is configured to apply pressure to the front surface of the cell assembly 210 when swelling of the battery cell occurs.

[0094] In detail, the first plate 410 is configured to pressurize the front surface of the cell assembly 210 when swelling of the battery cell occurs while being supported in the front-rear direction of the cell assembly 210 by the first protrusion 152. Thus, the first plate 410 can effectively suppress the swelling phenomenon of the cell module 200.

[0095] The second protrusion 154 is formed at a predetermined distance from the rear surface of the cell assembly 210 in the front-rear direction of the cell assembly 210 .

[0096] At this time, the second plate 420 is disposed between the second protrusion 154 and the rear surface of the cell assembly 210 in the front-rear direction of the cell assembly 210 and is configured to apply pressure to the rear surface of the cell assembly 210 when swelling of the battery cell occurs.

[0097] In detail, the second plate 420 is configured to pressurize the rear surface of the cell assembly 210 when swelling of the battery cell occurs while being supported in the front-rear direction of the cell assembly 210 by the second protrusion 154. In this way, the second plate 420 can effectively suppress the swelling phenomenon of the cell module 200.

[0098] As in the above-described configuration, the end plate 400 can apply pressure to the front and rear surfaces of the cell assembly 210 more stably while being supported in the front-rear direction of the cell assembly 210 by the guide protrusions 150 .

[0099] This makes it possible to more effectively suppress the swelling phenomenon that may occur in the cell module 200. In addition, because the end plate 400 is stably supported in the front-rear direction of the cell assembly 210 by the above-mentioned configuration of the guide protrusion 150, the fire tank 300 can be more stably fixed in the pack case 100 by such end plate 400.

[0100] As a result, the extinguishing agent is stably discharged from the fire extinguishing tank 300 to the cell assembly 210 side, so that the heat and fire in the cell assembly 210 can be more easily suppressed.

[0101] Referring again to FIGS. 4 to 10, the battery pack 10 may further include a connection part 500.

[0102] The connecting portion 500 can connect the first plate 410 and the second plate 420 in the front-rear direction of the cell assembly 210. As an example, the connecting portion 500 can be a long bolt formed to extend long in the front-rear direction of the cell assembly 210. This allows the first plate 410 and the second plate 420 to be connected to each other.

[0103] The connecting portion 500 will be described in more detail below.

[0104] The connecting portion 500 may include a first connecting member 510 and a second connecting member 520 .

[0105] The first connecting member 510 can connect the upper end of the first plate 410 and the upper end of the second plate 420 in the front-rear direction of the cell assembly 210. At this time, a plurality of first connecting members 510 are arranged along the left-right direction of the cell assembly 210.

[0106] The second connecting member 520 can connect the lower end of the first plate 410 and the lower end of the second plate 420 in the front-rear direction of the cell assembly 210. In this case, a plurality of second connecting members 520 are arranged along the left-right direction of the cell assembly 210.

[0107] In this manner, the connecting portion 500 can simultaneously connect the upper and lower ends of the first plate 410 and the second plate 420. Therefore, the first plate 410 and the second plate 420 can be stably connected to each other in the front-rear direction of the cell assembly 210.

[0108] This allows the end plate 400 to more stably and effectively apply pressure to the front and rear surfaces of the cell assembly 210. In addition, the first plate 410 and the second plate 420 of the end plate 400 are stably connected to each other by the above-mentioned configuration of the connecting part 500, so that the fire tank 300 can be more stably fixed in the pack case 100 by the end plate 400.

[0109] As a result, the extinguishing agent is stably discharged from the fire extinguishing tank 300 to the cell assembly 210 side, so that the heat and fire in the cell assembly 210 can be more easily suppressed.

[0110] Meanwhile, the cell assembly 210 is disposed between the first connecting member 510 and the second connecting member 520 in the vertical direction. Therefore, interference between the cell assembly 210 and the connecting portion 500 can be prevented.

[0111] FIG. 11 illustrates an end plate 402 according to another embodiment of the present invention.

[0112] Since the end plate 402 according to this embodiment is similar to the end plate 400 according to the previous embodiment, a duplicated description of the configuration that is substantially the same or similar to that of the previous embodiment will be omitted, and the following description will focus on the differences from the previous embodiment.

[0113] Referring to FIG. 11, the end plate 402 may include a first plate 410 and a second plate 420 .

[0114] The first plate 410 may include a first fastening portion 414 and the second plate 420 may include a second fastening portion 424 .

[0115] The first fixing portion 414 is formed to extend from the upper end of the first plate 410 in the front-rear direction of the cell assembly 210. The first fixing portion 414 is configured to extend long from the upper end of the first plate 410 in the left-right direction of the cell assembly 210.

[0116] In addition, the second fixing portion 424 is formed to extend from the upper end of the second plate 420 in the front-rear direction of the cell assembly 210. The second fixing portion 424 is configured to extend long from the upper end of the second plate 420 in the left-right direction of the cell assembly 210.

[0117] In this case, it is possible to further increase the contact area between the first plate 410 and the second plate 420 and the fire tank 300. This allows the fire tank 300 to be fixed to the upper side of the end plate 402 more stably.

[0118] FIG. 12 is a view showing an end plate 404 according to yet another embodiment of the present invention, and FIG. 13 is a projected side view showing the inside of a battery pack 10 to which the end plate 404 of FIG. 12 is applied.

[0119] Since the end plate 404 according to this embodiment is similar to the end plate 400 according to the previous embodiment, a duplicated description of the configuration that is substantially the same or similar to that of the previous embodiment will be omitted, and the following description will focus on the differences from the previous embodiment.

[0120] 12 and 13, the end plate 404 can include a first plate 410 and a second plate 420 .

[0121] The first plate 410 may include a first fastening portion 416 and the second plate 420 may include a second fastening portion 426 .

[0122] The first stationary portion 416 may include a first horizontal plate 4162 and a first vertical plate 4164 .

[0123] The first horizontal plate 4162 is formed to extend from an upper end of the first plate 410 in the front-rear direction of the cell assembly 210. The first horizontal plate 4162 is coupled to the front side of the fire tank 300 in the up-down direction.

[0124] The first vertical plate 4164 is formed to extend in the up-down direction from an end of the first horizontal plate 4162. The first vertical plate 4164 can support the front side of the fire tank 300 in the front-rear direction of the cell assembly 210.

[0125] The second stationary portion 426 may also include a second horizontal plate 4262 and a second vertical plate 4264 .

[0126] The second horizontal plate 4262 is formed to extend from an upper end of the second plate 420 in the front-rear direction of the cell assembly 210. The second horizontal plate 4262 is coupled to the rear side of the fire tank 300 in the up-down direction.

[0127] The second vertical plate 4264 is formed to extend in the up-down direction from an end of the second horizontal plate 4262. Such a second vertical plate 4264 can support the rear side of the fire tank 300 in the front-rear direction of the cell assembly 210.

[0128] According to this embodiment of the present invention, the end plate 404 can support the fire tank 300 not only in the vertical direction but also in the front-to-rear direction, so that the fire tank 300 can be fixed more stably within the pack case 100.

[0129] The above-mentioned pack case 100 may include a first cover 110, a second cover 120, and a gas flow passage .

[0130] 1 to 3, 9 and 10 again, the first cover 110 is provided with an accommodation space for accommodating the cell module 200. The first cover 110 can be combined with the second cover 120 described below to accommodate the cell module 200 therein. In addition, the bottom surface of the first cover 110 can form the bottom of the pack case 100.

[0131] In one embodiment, the above-mentioned guide protrusion 150 is provided on the first cover 110 and is provided on the bottom surface of the first cover 110 that constitutes the bottom of the pack case 100.

[0132] The second cover 120 is coupled to the first cover 110 in the up-down direction. At this time, the second cover 120 is disposed on the upper part of the first cover 110.

[0133] In one embodiment, the top of the fire extinguishing tank 300 is covered by the second cover 120 of the pack case 100 as shown in FIG.

[0134] In addition, when the first cover 110 and the second cover 120 are coupled in the vertical direction, the front, rear, left side, and right side of the pack case 100 are formed as shown in Fig. 1. As an example, the coupling between the first cover 110 and the second cover 120 is performed by a plurality of fastening members (not shown).

[0135] Meanwhile, in an embodiment of the present invention, the pack case 100 does not have to be configured as being separated into the first cover 110 and the second cover 120, but may be configured as an integrated unit.

[0136] Gas flow passage 130 is provided in second cover 120 to guide the inflow of air into pack case 100 and the exhaust of gas from within pack case 100 .

[0137] Such a gas flow passage 130 may include an air inlet portion 132 and a gas exhaust portion 134 .

[0138] The air inlet portion 132 is formed on the rear side of the second cover 120. At this time, the air inlet portion 132 allows the outside air to flow into the inside of the pack case 100.

[0139] The gas exhaust part 134 is formed on the front side of the second cover 120. At this time, the gas exhaust part 132 allows gas inside the pack case 100 to be exhausted to the outside.

[0140] Meanwhile, the air inlet portion 132 and the gas exhaust portion 134 are formed with a mesh structure. At this time, air can smoothly flow into the inside of the pack case 100 through the air inlet portion 132 having a mesh structure while preventing foreign objects of a certain size from flowing into the inside of the pack case 100. Similarly, vent gas generated inside the pack case 100 can be easily discharged to the outside of the pack case 100 through the gas exhaust portion 134 having a mesh structure while preventing foreign objects from flowing into the inside of the pack case 100.

[0141] In addition, the air inlet section 132 can smoothly flow air into the inside of the pack case 100, thereby preventing the generation of negative pressure inside the fire tank 300 described above. In addition, the air inlet section 132 can prevent a decrease in the injection speed and injection amount of the extinguishing agent into the cell module 200, which are caused by the generation of negative pressure inside the fire tank 300.

[0142] The cell module 200 may further include a bus bar frame 220 .

[0143] The bus bar frame 220 is for sensing the voltage of the cell assembly 210, and is provided in a pair to support one side and the other side of the cell assembly 210 in the left-right direction.

[0144] As an example, the bus bar frame 220 may include a first bus bar frame 222 and a second bus bar frame 224.

[0145] The first bus bar frame 222 may support one side (e.g., left side) in the left-right direction of the cell assembly 210. In addition, a bus bar (not shown) provided on the first bus bar frame 222 is connected to an electrode lead 212 formed on one side of the cell assembly 210 in the left-right direction.

[0146] The second bus bar frame 224 may support the other side (e.g., right side) in the left-right direction of the cell assembly 210. In addition, a bus bar (not shown) provided on the second bus bar frame 224 is connected to an electrode lead 212 formed on the other side of the cell assembly 210 in the left-right direction.

[0147] The fire tank 300 is configured to melt at least a portion thereof by heat applied from the cell assembly 210 in order to discharge the extinguishing agent. For example, the portion of the fire tank 300 indicated by A in FIG. 4 can be melted by heat. Then, the extinguishing agent is discharged to the cell assembly 210 side from between both sides of the bottom of the fire tank 300 through the melted portion. For this purpose, the fire tank 300 is made of a material that can melt at least a portion thereof by heat applied from the cell assembly 210. As an example, the fire tank 300 is entirely made of a plastic material.

[0148] Meanwhile, in the battery pack 10 of the present invention, the above-mentioned pack cases 100 may be configured to be stacked in the vertical direction. That is, the battery pack 10 of the present invention may be configured by stacking different pack cases 100 in the vertical direction. In this case, since each pack case 100 has a cell module 200 therein, battery packs 10 with various capacities can be realized depending on the number of stacked pack cases 100. Also, since each pack case 100 has a fire extinguishing tank 300 therein as described above, when a thermal event occurs in a cell assembly 210 in some pack cases 100, the thermal event can be prevented from transferring to cell assemblies 210 in other pack cases 100.

[0149] The fire extinguishing tank 300 may, for example, include a base plate 310 and a side wall 320. In this case, the base plate 310 may constitute the bottom of the fire extinguishing tank 300.

[0150] Here, the side wall 320 is configured to protrude upward from a corner of the base plate 310. The bottom and sides of the fire tank 300 are configured by the base plate 310 and the side wall 320, and a space for accommodating the extinguishing agent is formed. At this time, the top of the fire tank 300 can be sealed by the pack case 100. Alternatively, the fire tank 300 may include a separate top cover configured to seal the extinguishing agent accommodating space at the top.

[0151] The base plate 310 of the fire tank 300 has different thicknesses in the up-down direction for different parts. In particular, the base plate 310 is configured to have a thinner thickness at a specific part such as the part A in Fig. 4. As an example, the base plate 310 is configured in the form of a plastic injection molding having an overall thickness of 1 mm, and the part A is configured to have a thickness of 0.5 mm.

[0152] In this way, the portion of the base plate 310 that is formed to be thin can function as a weak part. In other words, when a thermal event such as a thermal runaway phenomenon occurs in the cell assembly 210 and heat is applied to the weak part, the weak part can be damaged first. When the weak part is damaged, the extinguishing agent stored inside the fire tank 300 can be discharged to the cell assembly 210 side through the damaged weak part. This allows a configuration for supplying the extinguishing agent to the cell assembly 210 to be realized with a simpler structure, and the extinguishing agent can be supplied to the cell assembly 210 side more quickly.

[0153] 4 to 9, at least a portion of the base plate 310 constituting the bottom of the fire extinguishing tank 300 is provided to protrude downward from the base plate 310. For example, a portion of the base plate 310 including a weak portion indicated by A in FIG. 4 is provided to protrude downward from the base plate 310. In this manner, at least a portion of the base plate 310 is disposed between the first plate 410 and the second plate 420 in the front-rear direction of the cell assembly 210.

[0154] According to this embodiment of the present invention, the fire tank 300 can be prevented from moving in the front-rear direction by the end plate 400. Also, according to the embodiment of the present invention, the portion (where the weak portion is formed) from which the extinguishing agent is discharged from the cell assembly 210 and the fire tank 300 is disposed between the first plate 410 and the second plate 420. This allows the extinguishing agent to be completely discharged from the fire tank 300 to the cell assembly 210 side, and the heat and fire of the cell assembly 210 can be easily suppressed.

[0155] As described above, according to an embodiment of the present invention, the fire extinguishing tank 300 can be more stably fixed within the pack case 100 via the end plates 400, 402, and 404, thereby quickly controlling thermal events within the pack case 100 and effectively preventing the swelling phenomenon of the cell module 200.

[0156] In addition, the battery pack 10 according to an embodiment of the present invention does not require any additional structure for supporting the fire tank 300 apart from the structure for preventing swelling, thereby improving the efficiency of the manufacturing process while ensuring cost competitiveness and realizing a compact structure with higher energy efficiency.

[0157] Meanwhile, the battery pack 10 according to the present invention may further include, in addition to the pack case 100 and the cell module 200, various devices for controlling the charging and discharging of the cell module 200, such as a BMS (Battery Management System), a current sensor, and a fuse.

[0158] As an example, the battery pack 10 according to the present invention is used as a battery pack for a house. In addition, at least one battery pack 10 according to the present invention may be provided as an energy source to configure an energy storage system (ESS).

[0159] As described above, the present invention has been described using only limited examples and drawings. However, the present invention is not limited thereto, and it is of course possible for a person having ordinary skill in the art to which the present invention pertains to make various modifications and variations within the technical spirit of the present invention and the equivalent scope of the claims described below.

[0160] Meanwhile, in the present invention, terms indicating directions such as up, down, left, right, front, and back are used, but such terms are merely for convenience of explanation, and it will be obvious to those skilled in the art of the present invention that such terms will vary depending on the position of the object of interest, the position of the observer, etc. [Explanation of symbols]

[0161] 10: Battery pack 100: Pack case 150: Guide protrusion 152:First protrusion 154:Second protrusion 200: Cell module 210: Cell Assembly 300: Fire tank 400, 402, 404: End plates 410: First Plate 420: 2nd plate 500: Connection part 510: First connecting member 520: Second connecting member

Claims

1. Pack case and A cell module is provided inside the pack case and includes a cell assembly having a plurality of battery cells; a fire extinguishing tank disposed above the cell assembly and having an internal space containing a fire extinguishing agent; and an end plate disposed on at least one of the front and rear sides of the cell assembly and configured to support the fire extinguishing tank. Battery pack.

2. 2. The battery pack according to claim 1, wherein the end plates are disposed on both front and rear sides of the cell assembly and configured to pressurize at least one of a front surface and a rear surface of the cell assembly when swelling of the battery cell occurs.

3. The fire extinguishing tank is configured to discharge the fire extinguishing agent from between both sides of the bottom toward the cell assembly when heat is applied from the cell assembly; The end plates support both sides of the bottom of the fire extinguishing tank in the vertical direction. The battery pack according to claim 2 .

4. 4. The battery pack according to claim 3, wherein a fixing portion having a predetermined area and in surface contact with both sides of the bottom of the fire extinguishing tank is provided on an upper side of the end plate.

5. The battery pack according to claim 4 , wherein the fixing portion is bent from an upper end of the end plate and extends a predetermined length along an outer side of the cell assembly.

6. The end plate is A first plate is disposed on a front surface of the cell assembly and supports a front side of the fire extinguishing tank in a vertical direction; and a second plate disposed on a rear surface of the cell assembly and supporting a rear side of the fire extinguishing tank in a vertical direction.

6. The battery pack according to claim 5.

7. 7. The battery pack of claim 6, wherein the fixing portion includes a first fixing portion extending from an upper end of the first plate in a front-rear direction of the cell assembly and vertically coupled to a front side of the fire tank.

8. The battery pack according to claim 7 , wherein the first fixing portion is in surface contact with a front side of the fire tank.

9. 7. The battery pack of claim 6, wherein the fixing portion further includes a second fixing portion formed to extend from an upper end of the second plate in a front-rear direction of the cell assembly and vertically coupled to a rear side of the fire tank.

10. The battery pack according to claim 9 , wherein the second fixing portion is in surface contact with a rear side of the fire tank.

11. the pack case includes guide protrusions that are formed to protrude in an up-down direction from a bottom of the pack case and are spaced apart from a front surface and a rear surface of the cell assembly at a predetermined interval in a front-rear direction of the cell assembly, The guide protrusion is disposed on the opposite side of the cell assembly across the end plate.

7. The battery pack according to claim 6.

12. The guide protrusion is a first protrusion formed on a front surface of the cell assembly at a predetermined interval in a front-rear direction of the cell assembly; and a second protrusion formed on a rear surface of the cell assembly at a predetermined interval in a front-rear direction of the cell assembly. The battery pack of claim 11.

13. the first plate is disposed between the first protrusion and a front surface of the cell assembly in a front-rear direction of the cell assembly and configured to pressurize the front surface of the cell assembly when swelling of the battery cell occurs; The second plate is disposed between the second protrusion and a rear surface of the cell assembly in a front-rear direction of the cell assembly and configured to pressurize the rear surface of the cell assembly when swelling of the battery cell occurs.

13. The battery pack of claim 12.

14. The battery pack according to claim 13 , further comprising a connection portion that connects the first plate and the second plate in a front-rear direction of the cell assembly.

15. The connecting portion is a first connecting member that connects an upper end of the first plate and an upper end of the second plate in a front-rear direction of the cell assembly and is arranged in a plurality of first connecting members along a left-right direction of the cell assembly; a second connecting member that connects a lower end of the first plate and a lower end of the second plate in the front-rear direction of the cell assembly and is arranged in a plurality of second connecting members along the left-right direction of the cell assembly.

15. The battery pack of claim 14.

16. A power storage device comprising at least one battery pack according to any one of claims 1 to 15.

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