Battery pack

Abstract

The disclosed invention relates to a battery pack, and in one example, the battery pack includes a pack case, a plurality of batteries housed in the pack case, a first heat absorber arranged between the plurality of batteries, and a second heat absorber arranged on both sides of the plurality of batteries, and the first heat absorber and the second heat absorber include an absorbent material impregnated with a liquid that vaporizes due to heat generated in the battery, and an exterior material in which the absorbent material is housed in a state in which it has absorbed the liquid.

Description

[Technical field]

[0001] The present invention relates to a battery pack capable of suppressing a heat propagation phenomenon in which other surrounding secondary batteries are continuously overheated when thermal runaway occurs.

[0002] This application claims the benefit of priority based on Korean Patent Application No. 10-2022-0047695 dated April 18, 2022, and Korean Patent Application No. 10-2022-0183986 dated December 26, 2022, and all contents disclosed in the documents of said Korean patent applications are incorporated herein by reference. [Background technology]

[0003] Unlike primary batteries, secondary batteries are rechargeable and have the potential to be small and have large capacity, and as such, they have been the subject of much research and development in recent years. The demand for secondary batteries as an energy source is rapidly increasing due to the increasing technological development and demand for mobile devices, as well as the emergence of electric vehicles and energy storage systems in response to the modern demand for environmental protection.

[0004] Secondary batteries are classified into coin type batteries, cylindrical type batteries, square type batteries, and pouch type batteries according to the shape of the battery case. The electrode assembly installed inside the battery case of the secondary battery is a power generating element capable of charging and discharging, which is made of a laminated structure of electrodes and a separator.

[0005] Since secondary batteries are required to be used continuously for long periods of time, it is necessary to effectively control the heat generated during the charging and discharging process.If secondary batteries are not cooled smoothly, a positive feedback chain reaction occurs in which a rise in temperature causes an increase in current, and the increase in current causes another rise in temperature, ultimately leading to a catastrophic state of thermal runaway.

[0006] In addition, when secondary batteries are grouped together in the form of a module or pack, a thermal propagation phenomenon occurs in which thermal runaway in one secondary battery causes other surrounding secondary batteries to continuously overheat. Furthermore, there is a high risk of fire due to ignition sources such as flammable gases released from an overheated secondary battery and heating electrodes, so it is necessary to suppress this risk of fire. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Korean Patent Publication No. 10-2021-0077410 (Published June 25, 2021) Summary of the Invention [Problem to be solved by the invention]

[0008] An object of the present invention is to provide a battery pack that can effectively suppress and prevent the phenomenon of heat propagation to surrounding secondary batteries due to thermal runaway occurring in a secondary battery.

[0009] However, the technical problem that the present invention aims to solve is not limited to the above-mentioned problem, and other problems not mentioned will be clearly understood by those of ordinary skill in the art from the description of the invention described below. [Means for solving the problem]

[0010] The present invention relates to a battery pack, and in one example, the battery pack includes a pack case, a plurality of batteries housed in the pack case, a first heat absorber arranged between the plurality of batteries, and a second heat absorber arranged on both sides of the plurality of batteries, and the first heat absorber and the second heat absorber include an absorbent material impregnated with a liquid that vaporizes due to heat generated in the battery, and an exterior material in which the absorbent material is housed in a state in which it has absorbed the liquid.

[0011] In one embodiment of the present invention, the first heat sink may be disposed between each of the plurality of batteries.

[0012] The exterior packaging material of the first heat absorber and the second heat absorber is a pouch, and the pouch may be provided with a fragile portion that breaks preferentially when the liquid impregnated in the absorbent material vaporizes and the internal pressure increases.

[0013] Here, the absorbent material may comprise a superabsorbent matrix, such as a superabsorbent polymer (SAP) or a superabsorbent fiber (SAF).

[0014] The liquid may then be water mixed with an additive, which may be a substance that reduces the surface tension of the water, or a fire extinguishing agent.

[0015] Meanwhile, the battery may be provided with a venting device, and the weakened portion provided in the pouch of the first heat sink may be disposed at a position corresponding to the venting device.

[0016] The second heat absorber may be disposed on the inner surface of a side case of the pack case.

[0017] In some embodiments, a plurality of second heat sinks may be provided, and the plurality of second heat sinks may be uniformly arranged in rows and columns on the inner surface of the side case.

[0018] The plurality of batteries may be housed in the pack case in a plurality of rows, side plates may be disposed between the rows of the batteries, and a plurality of the second heat sinks may be provided and may be uniformly disposed in rows and columns on inner surfaces of the side plates so as to contact side surfaces of the batteries.

[0019] The inner surface of the side case or the inner surface of the side plate may have a lattice-like rib structure, and the second heat sink may be disposed within a concave surface formed in rows and columns by the rib structure, and the second heat sink may not protrude outside the concave surface.

[0020] According to another embodiment of the present invention, the plurality of batteries are housed in the pack case in at least one or more rows, and a venting device is provided on the upper surface of each battery, and a venting guide is provided that is integrally connected to the venting devices of the batteries in the row.

[0021] The venting guide defines the venting device for electrode terminals disposed on an upper surface of the battery.

[0022] The outer packaging material of the first heat absorber is a pouch, and the pouch of the first heat absorber is provided with a weak part that breaks preferentially when the liquid impregnated in the absorbent material vaporizes and the internal pressure increases, whereby the weak part of the first heat absorber is located in a direction toward the venting guide, and the venting guide can be provided with a gas exhaust port communicating with the venting device and a steam exhaust port communicating with the weak part of the first heat absorber.

[0023] The first heat absorber may be disposed between the plurality of batteries, and the vapor outlet may be provided between the gas outlets. Effect of the Invention

[0024] According to the battery pack of the present invention having the above-mentioned configuration, the occurrence of thermal runaway can be prevented by quickly absorbing and dissipating heat in an environment where temperature rises are common, such as rapid charging, and performance and lifespan can be maintained without a high temperature rise.

[0025] In addition, in the present invention, when a thermal runaway phenomenon occurs in a secondary battery, the liquid impregnated in the absorbent material inside the heat absorption pouch absorbs heat and vaporizes, and when the vaporized gas rises above a certain pressure, it ruptures the heat absorption pouch and is ejected, thereby cooling the flammable gas released from the overheated battery cell and ignition sources such as the heating electrodes, thereby suppressing flames, thereby significantly reducing the heat propagation to surrounding secondary batteries and the risk of fire.

[0026] In addition, the battery pack of the present invention has heat absorption, insulation and fire extinguishing functions between and on the sides of the densely packed secondary batteries, and quickly dissipates excess energy from the secondary batteries in all directions, thereby delaying the onset of thermal runaway.

[0027] However, the technical effects that can be obtained by the present invention are not limited to the effects described above, and other effects not mentioned will be clearly understood by those of ordinary skill in the art from the description of the invention described below. [Brief description of the drawings]

[0028] 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 concept of the present invention. Therefore, the present invention should not be interpreted as being limited only to the matters described in such drawings.

[0029] [Figure 1] FIG. 1 is an exploded perspective view of a battery pack according to a first embodiment of the present invention. [Diagram 2] 2 is a diagram illustrating an arrangement structure of a first heat sink and a second heat sink provided in the battery pack of the present invention. [Diagram 3] 4 is a diagram illustrating an arrangement structure of a first heat absorber and a second heat absorber for one battery. [Figure 4] FIG. 4 is a cross-sectional view illustrating an arrangement structure of a plurality of batteries and a first heat sink. [Diagram 5] 1 is a diagram illustrating an arrangement structure of a plurality of batteries and a second heat sink. [Figure 6] FIG. 11 is an exploded perspective view of a battery pack according to a second embodiment of the present invention. [Figure 7] 1 is a diagram illustrating a coupling structure of a venting guide for a plurality of batteries; [Figure 8] FIG. 8 is a cross-sectional view taken along the line "AA" in FIG. 7. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0030] Since the present invention can be modified in various ways and can have various embodiments, specific embodiments will be described in detail below.

[0031] However, this is not intended to limit the invention to the particular embodiments, but should be understood to include all modifications, equivalents, or alternatives falling within the spirit and scope of the invention.

[0032] In the present invention, the terms "comprise" and "have" are intended to specify the presence of features, numbers, steps, operations, components, parts, or combinations thereof described in the specification, but should be understood as not precluding the presence or additional possibility of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0033] In addition, in the present invention, when a layer, film, region, plate, or other portion is described as being "on" another portion, this includes not only the case where it is "directly on" the other portion, but also the case where there is another portion in between. Conversely, when a layer, film, region, plate, or other portion is described as being "under" the other portion, this includes not only the case where it is "directly under" the other portion, but also the case where there is another portion in between. In addition, in the present application, being "on" can include not only the case where it is located at the top, but also the case where it is located at the bottom.

[0034] The present invention relates to a battery pack, and in one example, the battery pack includes a pack case, a plurality of batteries housed in the pack case, a first heat sink disposed between the plurality of batteries, and a second heat sink disposed on both sides of the plurality of batteries.

[0035] Here, the first heat absorber and the second heat absorber include an absorbent material impregnated with a liquid that vaporizes due to heat generated in the battery, and an exterior material in which the absorbent material is housed while absorbing the liquid.

[0036] As a result, the present invention can suppress the occurrence of thermal runaway by quickly absorbing and dispersing heat in an environment where there is a large temperature rise, such as during quick charging, through the heat absorbing action of the first heat absorber and the second heat absorber that are in contact with the battery, and can maintain performance and lifespan without a large temperature rise. In particular, the first heat absorber and the second heat absorber are in contact with the front, back, and both sides of the battery, respectively, and absorb heat on all four sides of the battery, thereby effectively suppressing temperature rise.

[0037] In addition, in the present invention, when a thermal runaway phenomenon occurs in a battery in a battery pack, the liquid impregnated in the absorbent material in the heat absorber absorbs heat and vaporizes, and when the vaporized gas rises above a certain pressure, the heat absorber breaks and is ejected, causing the overheated battery to emit flammable gas and ignition sources such as heating electrodes. This cools the flammable gas and ignition sources such as heating electrodes, thereby suppressing flames and significantly reducing the risk of fire in the battery pack.

[0038] Hereinafter, specific embodiments of the battery pack of the present invention will be described in detail with reference to the accompanying drawings. For reference, the directions of front, back, up, down, left and right specifying relative positions used in the following description are intended to facilitate understanding of the invention, and unless otherwise specified, are based on the directions shown in the drawings.

[0039] (First embodiment) FIG. 1 is an exploded perspective view of a battery pack 10 according to a first embodiment of the present invention, FIG. 2 is a diagram illustrating an arrangement structure of a first heat absorber 310 and a second heat absorber 320 provided in the battery pack 10 of the present invention, and FIG. 3 is a diagram illustrating an arrangement structure of the first heat absorber 310 and the second heat absorber 320 for any one battery 200.

[0040] As shown in the drawings, a battery pack 10 of the present invention includes a pack case 100 and a plurality of batteries 200 housed in the pack case 100. The illustrated pack case 100 includes a main case 110 having a "U" cross-sectional shape, a top case 120 coupled to an open side of the main case 110, and a pair of side cases 130. The battery 200 is a secondary battery having a rectangular case shape, and is exemplified as a one-way secondary battery in which positive and negative electrode terminals 210 are both disposed on the top surface. A venting device 220 for discharging excessive internal pressure is provided between the electrode terminals 210 on the top surface of the battery 200.

[0041] The battery pack 10 of the present invention includes two types of heat absorbers 310, 320. The first heat absorber 310 is a heat absorber disposed between the plurality of batteries 200. That is, in the illustrated embodiment, the plurality of batteries 200 are aligned in a row along the thickness direction, and thus the first heat absorber 310 contacts the front and rear surfaces of the battery 200. The second heat absorber 320 is a heat absorber disposed on both sides of the plurality of batteries 200. Therefore, the battery 200 housed in the pack case 100 is surrounded by the heat absorbers 310, 320 on four sides, i.e., front, rear, left and right.

[0042] The first heat absorber 310 and the second heat absorber 320 in contact with the battery 200 include an absorbent material 330 impregnated with a liquid that absorbs heat generated in the battery 200 and vaporizes it, and an exterior material 340 that hermetically houses the absorbent material 330 in a liquid-absorbed state.

[0043] The first heat absorber 310 and the second heat absorber 320 primarily perform a heat insulating function that suppresses heat transfer between adjacent batteries 200. Secondarily, they perform a heat absorbing function that absorbs heat generated in the battery 200 to prevent overheating. In addition, the liquid vaporizes due to the heat absorbing action, and the internal pressure (vapor pressure) of the exterior material 340 increases. When the internal pressure exceeds a certain pressure, the exterior material 340 breaks and ejects gas, thereby lowering the temperature of the high-temperature gas and flame generated in the surrounding overheated battery 200. Therefore, the first heat absorber 310 and the second heat absorber 320 can ultimately perform a fire extinguishing function.

[0044] In one embodiment of the present invention, the absorbent material 330 may be a highly absorbent matrix, for example, an absorbent material 330 including a super absorbent polymer (SAP) or a super absorbent fiber (SAF). The highly absorbent matrix is ​​porous or fibrous and can absorb a large amount of liquid by exhibiting capillary action, and the highly absorbent fiber can be manufactured in the form of a fiber such as a nonwoven fabric by processing a highly absorbent resin.

[0045] In the present invention, there is no particular restriction on the specific type of superabsorbent resin and the superabsorbent fiber produced therefrom, and any type that has excellent absorbing ability for fluids, particularly water, may be used. Examples of the superabsorbent resin include one or more selected from the group consisting of polyacrylic acid, polyacrylates, polyacrylate graft polymers, starch, crosslinked carboxymethylated cellulose, acrylic acid copolymers, hydrolyzed starch-acrylonitrile graft copolymers, starch-acrylic acid graft copolymers, saponified vinyl acetate-acrylic acid ester copolymers, hydrolyzed acrylonitrile copolymers, hydrolyzed acrylamide copolymers, ethylene-maleic anhydride copolymers, isobutylene-maleic anhydride copolymers, polyvinyl sulfonic acid, polyvinyl phosphonic acid, polyvinyl phosphoric acid, polyvinyl sulfate, sulfonated polystyrene, polyvinylamine, polydialkylaminoalkyl(meth)acrylamide, polyethyleneimine, polyallylamine, polyallylguanidine, polydimethyldiallylammonium hydroxide, quaternized polystyrene derivatives, guanidine-modified polystyrene, quaternized poly(meth)acrylamide, polyvinyl guanidine, and mixtures thereof, and preferably one or more selected from the group consisting of crosslinked polyacrylates, crosslinked polyacrylic acids, and crosslinked acrylic acid copolymers, but the present invention is not limited thereto.

[0046] In the present invention, the type of acrylic acid copolymer used as the superabsorbent resin is not particularly limited, but it may be a copolymer containing an acrylic acid monomer and one or more comonomers selected from the group consisting of maleic acid, itaconic acid, acrylamide, 2-acrylamido-2-methylpropanesulfonic acid, 2-(meth)acryloylethanesulfonic acid, 2-hydroxyethyl (meth)acrylate, and styrenesulfonic acid.

[0047] In the present invention, the highly absorbent resin can have a water absorption capacity of 10 g / g to 500 g / g, preferably 50 g / g to 200 g / g, but is not limited thereto. That is, 1 g of highly absorbent resin can absorb 10 g to 500 g of water, preferably 50 g to 200 g of water.

[0048] In the present invention, the greater the water absorption capacity of the superabsorbent resin, the longer the cooling effect can be maintained; however, if it exceeds 500 g / g, the fluidity of the superabsorbent resin increases and it becomes difficult to maintain its shape, making it impossible to provide effective cooling, and if it is less than 10 g / g, the cooling effect will not last long enough to be inefficient.

[0049] In one embodiment of the present invention, the liquid impregnated in the absorbent 330 may be water. Water is a substance with the highest specific heat and latent heat among readily available liquids. Therefore, the water contained in the absorbent 330 is suitable for use as the liquid contained in the first heat absorber 310 and the second heat absorber 320 of the present invention because the water absorbs a large amount of heat during the process of changing phase to gas when the temperature rises to the boiling point.

[0050] In addition, the water impregnated in the absorbent 330 may be mixed with an additive that can enhance the fire extinguishing function. For example, the additive mixed with the water may be a substance that reduces the surface tension of the water or a fire extinguishing agent. Examples of substances that reduce the surface tension of water include wetting agents and surfactants. When the surface tension of water is reduced, the penetration effect of water increases, thereby enhancing the fire extinguishing effect against high-temperature ignition sources such as heating electrodes and ignition particles.

[0051] The extinguishing agent is a generic name for an agent that exerts a fire-extinguishing function by itself, and can be any of various powder extinguishing agents and liquid extinguishing agents currently on the market. For example, an extinguishing agent with the product name F-500 EA (manufactured by HAZARD CONTROL TECHNOLOGIES, INC.) can be added to water.

[0052] On the other hand, the liquid, e.g., water, that is impregnated in a large amount in the absorbent 330 absorbs heat generated in the battery 200 and vaporizes when its temperature exceeds its boiling point. Due to the increase in volume caused by the phase change from liquid to gas, the internal pressure of the exterior material 340 that seals the absorbent 330 increases.

[0053] A pouch made of a flexible laminate sheet can be used as the exterior material 340. The pouch, which is the exterior material 340, is provided with a fragile portion 342 that breaks preferentially when the liquid impregnated in the absorbent material 330 evaporates and the internal pressure increases.

[0054] The laminate sheet may have a three or more layer structure including an aluminum thin film layer, an inner resin layer formed inside the aluminum thin film layer, and an outer resin layer formed outside the aluminum thin film layer. For example, the inner resin layer may be cast polypropylene (CPP) or polypropylene (PP), and the outer resin layer may be polyethylene terephthalate (PET) or nylon.

[0055] The weakened portion 342 can be made to have a structure that breaks preferentially due to an increase in internal pressure caused by evaporation of liquid by locally lowering the sealing strength of the pouch 340. That is, the pouch 340 is sealed by heat sealing the edges of the laminate sheet that encases the absorbent material 330, and the weakened portion 342 can be formed in a manner that makes the heat seal strength lower than the surrounding area. For example, the weakened portion 342 can be formed by making the thickness thinner than the surrounding area, by forming a notch to reduce strength, or by locally removing an aluminum thin film layer that maintains durability.

[0056] 1 and 2, the first heat sink 310 may be disposed between each of the batteries 200. Also, the first heat sink 310 may be provided between the sidewall of the pack case 100 and the batteries 200. As such, the first heat sink 310 is provided on the front and rear surfaces of all the batteries 200, so that uniform heat insulation, cooling and fire extinguishing effects occur inside the battery pack 10.

[0057] Meanwhile, as described above, the battery 200 is provided with the venting device 220, and it can be said that the fragile portion 342 provided in the pouch 340 of the first heat sink 310 is preferably disposed at a position corresponding to the venting device 220. In the illustrated embodiment, the venting device 220 is disposed at the center of the upper surface of the battery 200, and the fragile portion 342 is located at the upper center of the first heat sink 310 corresponding to the venting device 220.

[0058] 4 is a cross-sectional view illustrating the arrangement of a plurality of batteries 200 and a first heat sink 310. As shown in FIG. 4, when a thermal runaway phenomenon occurs in a battery 200 and the battery 200 is overheated, the liquid impregnated in the absorbent 330 in the first heat sink 310 absorbs heat and vaporizes, and when the internal pressure of the vaporized gas rises above a certain pressure, the weak part 342 of the first heat sink 310 breaks and ejects gas. The gas ejected from the first heat sink 310 cools the ignition source, such as the flammable gas and the heating electrode generated in the overheated battery 200, during the process of the ignition source being released through the venting device 220, thereby suppressing and extinguishing the flame, thereby significantly reducing the risk of fire in the battery pack 10.

[0059] Although the first heat absorber 310 has been described in detail above, the configuration of the heat absorber itself is almost the same as that of the second heat absorber 320. However, the second heat absorber 320 differs from the first heat absorber 310 in that it is disposed on both sides of the battery 200 and no special conditions are imposed on the position of the fragile portion 342.

[0060] The second heat absorber 320 contacts both sides of the battery 200 and is disposed on the inner surface of the side case 130 due to the structure of the pack case 100. FIG. 5 is a diagram illustrating the arrangement of a plurality of batteries 200 and the second heat absorber 320, and when viewed in conjunction with FIG. 1 and FIG. 3, when a plurality of second heat absorbers 320 are provided, the second heat absorbers 320 may be uniformly disposed in rows and columns on the inner surface of the side case 130. In the illustrated embodiment, the second heat absorbers 320 are installed in concave surfaces arranged in a lattice structure on the inner surface of the side case 130 to form a uniform matrix structure, so that both sides of all the batteries 200 have the same contact area with the second heat absorber 320.

[0061] In addition, when the batteries 200 are housed in the pack case 100 in a plurality of rows (two rows in the illustrated embodiment) as in the illustrated embodiment, the side plates 140 are disposed between the rows of the batteries 200, and the second heat sinks 320 are disposed in uniform rows and columns on the inner surface of the side plates 140 so as to contact the inner side surfaces (based on the pack case) of the batteries 200. As a result, the side surfaces of all the batteries 200 in the battery pack 10 are uniformly in contact with the second heat sinks 320.

[0062] 1, 3 and 5, a lattice-like rib structure 150 is formed on the inner surface of the side case 130 and the side plate 140. The rib structure 150 connected vertically and horizontally and protruding enhances the structural rigidity of the side case 130 and the side plate 140. In addition, the lattice-like rib structure 150 forms a plurality of concave surfaces 152 arranged in rows and columns on the inner surface of the side case 130 and the side plate 140. The second heat sink 320 is inserted and disposed in the concave surface 152. The second heat sink 320 may have a thickness that does not protrude outside the concave surface 152, and thus a large number of second heat sinks 320 can be mounted in the battery pack 10 with space efficiency without increasing the size of the pack case 100.

[0063] The rib structure 150 allows the multiple second heat absorbers 320 to be uniformly distributed in a matrix structure of rows and columns. When the multiple second heat absorbers 320 are distributed, the second heat absorber 320 closest to the overheated battery 200 first performs heat absorption and fire extinguishing functions, and then the other second heat absorbers 320 operate according to heat transfer. In this manner, the multiple second heat absorbers 320 are distributed, which is advantageous for maintaining the thermal management of the battery pack 10 for a longer period of time compared to a case where one large-capacity heat absorber is broken at once and its function is terminated in one go.

[0064] For reference, the illustrated battery pack 10 is provided with a water-cooled heat sink assembly 350 that absorbs heat on the inner bottom of the main case 110, and the heat sink assembly 350 functions to absorb heat and cool the housed battery 200 through the bottom surface of the battery 200.

[0065] Second embodiment 6 is an exploded perspective view of a battery pack 10 according to a second embodiment of the present invention. In the battery pack 10 according to the second embodiment of the present invention, a plurality of batteries 200 are accommodated in a pack case 100 to form at least one or more rows, and a venting guide 400 is provided on the upper surface of each battery 200 and integrally coupled to the venting devices 220 arranged in a row.

[0066] 7 is a diagram illustrating a coupling structure of a venting guide 400 for a plurality of batteries 200, and as shown in the drawing, the venting guide 400 partitions the venting devices 220 for the positive and negative electrode terminals 210 arranged on the upper surface of the battery 200. That is, one venting guide 400 is attached to a row of batteries 200 in a structure that covers the venting devices 220, and thus the central venting device 220 covered by the venting guide 400 is separated from the positive and negative electrode terminals 210 arranged on the left and right thereof.

[0067] However, since the venting guide 400 is provided with a gas exhaust port 410 that communicates with the venting device 220, the electrode terminal 210 and the venting device 220 are not completely isolated spatially. However, since the gas exhaust port 410 guides the exhaust path in the venting device 220 upward, it is possible to prevent or at least delay damage to the electrode terminal 210 due to thermal runaway.

[0068] Fig. 8 is a cross-sectional view taken along the "AA" line in Fig. 7. As described in the first embodiment, the exterior material 340 of the first heat absorber 310 may be a pouch 340, and in this case, a fragile part 342 may be provided that breaks preferentially when the liquid impregnated in the absorbent material 330 of the first heat absorber 310 vaporizes and the internal pressure increases.

[0069] Also, the weak part 342 of the first heat absorber 310 may be located in a direction toward the venting guide 400. For example, when the venting device 220 is located at the center of the upper surface of the battery 200, the weak part 342 of the first heat absorber 310 may also be located at the upper center, so that the direction of steam discharge may be directed toward the venting guide 400. Correspondingly, the venting guide 400 may be provided with a steam exhaust port 420 communicating with the weak part 342 of the first heat absorber 310. Here, when the first heat absorber 310 is disposed between the plurality of batteries 200, it may be preferable that the steam exhaust port 420 is also provided between the gas exhaust ports 410.

[0070] 8, a steam outlet 420 is disposed between each of the gas outlets 410 communicating with the venting device 220. Therefore, when thermal runaway occurs in a certain battery 200 and high-temperature gas or flames are ejected from the venting device 220, the vaporized liquid component of the first heat absorber 310 in contact with the overheated battery 200 breaks the fragile portion 342 and ejects steam, which is guided to the gas outlet 410 and the steam outlet 420 of the venting guide 400, respectively, and smoothly mixed.

[0071] In this manner, the battery pack 10 of the second embodiment is provided with a venting guide 400 that guides the exhaust path of gas and vapor in a specified direction, thereby reducing damage to the electrode terminal 210 caused by high-temperature gas and flames and enhancing the safety function of cooling and extinguishing the gas and flames.

[0072] The present invention has been described in more detail above with reference to the drawings and embodiments, etc. However, the configurations described in the drawings or embodiments, etc. in this specification are merely one embodiment of the present invention and do not represent all of the technical ideas of the present invention, so it should be understood that there may be various equivalents and modifications that can replace them at the time of filing this application. [Explanation of symbols]

[0073] 10: Battery pack 100: Pack case 110: Main case 120: Top case 130: Side case 140: Side plate 150: Rib structure 152: Concave 200: Battery 210: Electrode terminal 220: Venting equipment 310: First heat absorber 320: Second heat absorber 330: Absorbent material 340: Exterior material (pouch) 342: Weak part 350: Heat sink assembly 400: Venting Guide 410: Gas exhaust port 420: Steam exhaust port

Claims

1. Pack case and A plurality of batteries housed in the pack case; a first heat sink disposed between the plurality of batteries; a second heat sink disposed on both sides of the plurality of batteries; The first heat absorber and the second heat absorber are an absorbent material impregnated with a liquid that evaporates due to heat generated in the battery; an exterior material in which the absorbent material is housed in a state in which the absorbent material has absorbed the liquid; The batteries are housed in the pack case in at least one row; Each battery is equipped with a venting device on the top. a venting guide integrally connected to the venting device of the row of batteries; The venting guide is The venting device is partitioned relative to an electrode terminal disposed on an upper surface of the battery; the packaging material of the first heat absorber is a pouch, The pouch of the first heat absorber is provided with a fragile portion that is preferentially broken when the liquid impregnated in the absorbent material is vaporized and the internal pressure increases, the weak portion of the first heat sink is located in a direction toward the venting guide, The venting guide is a gas outlet communicating with the venting device; a steam exhaust port communicating with the weak portion of the first heat absorber; The gas exhaust port is provided for each of the venting devices, The gas exhaust port guides a gas exhaust path in the venting device upward.

2. The first heat absorber is The battery pack according to claim 1 , wherein the battery pack is disposed between the plurality of batteries.

3. The outer casing of the second heat absorber is a pouch, The battery pack according to claim 1 , wherein the pouch of the second heat sink is provided with a weakened portion that breaks preferentially when the liquid impregnated in the absorbent material vaporizes and the internal pressure increases.

4. The absorbent material is 4. The battery pack of claim 3, which is a highly absorbent matrix.

5. 5. The battery pack of claim 4, wherein the superabsorbent matrix comprises a superabsorbent polymer or a superabsorbent fiber.

6. The liquid is water mixed with an additive, 6. The battery pack of claim 5, wherein the additive is a substance that reduces the surface tension of water or a fire extinguishing agent.

7. A battery pack as described in claim 3, wherein the fragile portion provided in the pouch of the first heat absorber is positioned at a position corresponding to the venting device.

8. The second heat absorber is The battery pack according to claim 1 , disposed on an inner surface of a side case of the pack case.

9. The second heat sink is provided in a plurality of pieces, The battery pack according to claim 8 , wherein the second heat sinks are uniformly arranged in rows and columns on the inner surface of the side case.

10. The batteries are housed in the pack case in a plurality of rows, Side plates are disposed between the rows of batteries; The battery pack according to claim 1 , wherein the second heat sink comprises a plurality of second heat sinks uniformly arranged in rows and columns on the inner surface of the side plate so as to contact a side surface of the battery.

11. A pack case, A plurality of batteries housed in the pack case; a first heat sink disposed between the plurality of batteries; a second heat sink disposed on both sides of the plurality of batteries; The first heat absorber and the second heat absorber are an absorbent material impregnated with a liquid that evaporates due to heat generated in the battery; an exterior material in which the absorbent material is housed in a state in which the absorbent material has absorbed the liquid; The batteries are housed in the pack case in a plurality of rows, Side plates are disposed between the rows of batteries; the second heat sink is provided in a plurality of pieces and is uniformly arranged in rows and columns on the inner surface of the side plate so as to contact the side surface of the battery; an inner surface of a side case of the pack case or an inner surface of the side plate has a lattice-like rib structure; the second heat sink is disposed within a concave surface formed in rows and columns by the rib structure; The second heat sink does not protrude outside the concave surface.

12. The first heat sink is disposed between each of the plurality of batteries, The battery pack according to claim 1 , wherein the vapor exhaust port is provided between each of the gas exhaust ports.

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