Battery module and battery pack including cooling part

Abstract

A battery pack according to one embodiment of the present disclosure comprises: a battery cell stack in which a plurality of battery cells are stacked; a frame that accommodates the stack of battery cells; and a cooling part provided on the battery cell stack, in which the cooling part includes: a coolant accommodating member including an upper plate and a lower plate; an elastic member disposed in an inner space of the coolant accommodating member; and a sealing member that seals at least one through hole formed in the coolant accommodating member and is meltable by an increase in temperature of the battery cell, and wherein the coolant is accommodated within the elastic member and the elastic member expands as the coolant is accommodated.

Description

Technical Field

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of Korean Patent Application No. 10-2022-0088258 filed on July 18, 2022, and Korean Patent Application No. 10-2023-0092580 filed on July 17, 2023, in the Korean Intellectual Property Office, the entire contents of which are incorporated herein by reference.

[0003] The present disclosure relates to a battery module and a battery pack including a cooling part, and more particularly, to a battery module and a battery pack that contain a coolant in a coolant containing space and include a shrinkable and expandable elastic member to quickly supply the coolant when a battery cell catches fire, thereby preventing thermal runaway from occurring. Background Art

[0004] Secondary batteries have attracted attention as a power source for electric vehicles, hybrid electric vehicles, plug-in hybrid electric vehicles, and the like, which have been proposed as a solution to air pollution caused by conventional vehicles using fossil fuels, diesel vehicles, and the like.

[0005] In small mobile devices, one or two or three battery cells are used per device, while medium or large devices such as vehicles require high power and large capacity. Therefore, due to the necessity of high output and large capacity, medium or large battery packs with a large number of battery cells electrically connected are used.

[0006] Since a middle or large battery module is preferably manufactured in as small a size and weight as possible, square batteries, soft pack type batteries, etc., which can be stacked with high integration and have light weight compared with capacity, are mainly used as battery cells of the middle or large battery module.

[0007] Since the battery cells constituting such a middle- or large-sized battery module are chargeable and dischargeable secondary batteries, such a high-output and large-capacity secondary battery generates a large amount of heat during the charge and discharge process.

[0008] When the heat generated during charging and discharging is not effectively eliminated, heat accumulation may occur, which may accelerate the degradation of the battery cells, and depending on the situation, the battery module may catch fire or explode. Therefore, a medium or large battery pack for a vehicle and a medium or large battery pack for a power storage system are high-output large-capacity batteries including a plurality of medium or large battery modules, and a cooling system is required to cool the battery cells installed in the battery pack.

[0009] Fig.12 and Fig.13 is a vertical cross-sectional view of a battery module or battery pack 10 according to the prior art. Fig.12As the coolant (cooling water) stored in the coolant containing member 220 (water tank) is supplied to the battery cell 103 that has caught fire through the through hole 230, the pressure (water pressure) of the coolant in the coolant containing member 220 gradually decreases. Therefore, as time goes by, the rate at which the coolant is injected into the battery cell 103 slows down.

[0010] In addition, the pressure of the coolant in the coolant containing member 220 is generally proportional to the height of the coolant, but the coolant containing member 220 (water tank) is generally formed along the containing direction of the battery cell stack so that its height is lower than the width of the coolant containing member 220. Therefore, the pressure of the coolant injected into the battery cell 103 has no choice but to become further lower. This becomes a factor that inhibits rapid coolant injection.

[0011] In addition, when a vehicle equipped with a battery pack is located on an inclined surface or the like, and the coolant containing member 220 of the battery pack is also positioned obliquely, a situation may occur in which all the coolant in the coolant containing member 220 is not supplied to the battery cell stack, such as Fig.13 shown.

[0012] In addition, if Fig.12 and Fig.13 As shown, the coolant is supplied from the upper coolant containing member 220 to the lower battery cell stack along the open through hole 230 due to gravity. Therefore, the coolant containing member 220 has no choice but to be located only at the upper part of the battery cell stack, and there is a limitation that the coolant containing member 220 cannot be disposed at the lower part. Fig.12 and Fig.13 A case is shown in which no coolant containing space is provided in the lower portion and only the heat dissipation plate 211 is provided. Summary of the invention

[0013] Technical issues

[0014] Therefore, the present disclosure is designed to solve the problems as described above, and an object of the present disclosure is to enable a coolant used in a cooling part arranged inside a battery module and / or a battery pack to be quickly and directly injected into a battery cell that has caught fire to prevent heat energy from being transferred to adjacent battery cells when the battery cell catches fire or explodes, and an object of the present disclosure is to provide a battery module and / or a battery pack including a cooling part, which has a structure that can effectively suppress the thermal runaway phenomenon of the battery cell while overcoming the difficulty of coolant injection on a slope and minimizing the volume increase of the battery module and / or battery pack.

[0015] However, the technical problems to be solved by the embodiments of the present disclosure are not limited to the above-mentioned problems, and various extensions can be made within the scope of the technical concept included in the present disclosure.

[0016] Technical Solution

[0017] According to one embodiment of the present disclosure, a battery pack is provided, comprising: a battery cell stack in which a plurality of battery cells are stacked; a frame that accommodates the battery cell stack; and a cooling part that is disposed on the battery cell stack, wherein the cooling part comprises: a coolant containing member that includes an upper plate and a lower plate; an elastic member that is disposed in an internal space of the coolant containing member; and a sealing member that seals at least one through hole formed in the coolant containing member and is meltable by a temperature increase of the battery cells, and wherein the coolant is contained in the elastic member and the elastic member expands as the coolant is contained.

[0018] Before the elastic member is melted, the elastic member may contain the coolant therein and expand to the maximum extent and cover the entire surface of the inner space of the coolant containing member.

[0019] When the temperature of the battery cell increases, the sealing member is melted by high temperature gas or sparks exhausted from the battery cell, and simultaneously or subsequently, a portion of the elastic member adjacent to the sealing member melts, allowing the coolant within the elastic member to flow out to the battery cell stack.

[0020] While the coolant flows into the battery cell stack, the elastic member may gradually contract as the pressure of the coolant pressing the elastic member gradually decreases.

[0021] The coolant may not be accommodated in the space between the coolant accommodation member and the elastic member.

[0022] An adhesive for adhering the elastic member may be applied to a portion of the inner surface of the coolant containing member including the periphery of the through hole.

[0023] The adhesive may be an acrylic adhesive, a silicone adhesive, a rubber adhesive, or a hot melt adhesive.

[0024] The coolant containing member is a water tank, and cooling water may be contained in the elastic member.

[0025] The battery pack includes at least one partition wall, which is arranged in the internal space of the coolant containing member to divide the internal space into a plurality of regions, wherein the at least one partition wall can be arranged perpendicular to the heat dissipation plate and arranged in the length direction of the battery cell, and the elastic member can be arranged in each of the plurality of regions.

[0026] A pressing member with elastic force is arranged between the inner surface of the cooling part and the outer surface of the elastic member, and when the coolant is contained in the elastic member, the pressing member is compressed due to the pressure caused by the coolant, and when the coolant is supplied to the battery cell via the through hole and the elastic member gradually contracts, the pressing member presses the outer surface of the elastic member due to the restoring force of the compressed pressing member, so that the elastic member can be in close contact with the periphery of the through hole.

[0027] The pressing member may be a spring.

[0028] The sealing member may be made of a thermoplastic polymer resin.

[0029] The elastic member may be made of natural rubber, synthetic rubber (SBR: synthetic rubber), oil-resistant rubber (NBR: oil-resistant rubber), or polyurethane rubber.

[0030] A surface of the coolant containing member adjacent to the battery cell stack may be a heat dissipation plate.

[0031] The frame includes: an upper plate arranged on the upper part of the battery cell stack; a lower plate arranged on the lower part of the battery cell stack; and a side panel arranged on the side of the battery cell stack between the upper plate and the lower plate, wherein a cooling part is arranged on at least one of the upper plate and the lower plate, and wherein a heat dissipation plate of a coolant containing member can be spaced apart from the frame by a predetermined distance to form a coolant containing member.

[0032] A battery pack according to another embodiment of the present disclosure may be configured such that a battery cell stack is provided in plural, and a cooling part is provided on the plurality of battery cell stacks.

[0033] Beneficial Effects

[0034] As described above, the battery module and / or battery pack according to the present disclosure contains a coolant in the internal space of the cooling part, and includes a shrinkable and expandable elastic member, so that when a battery cell catches fire, the battery cell that has caught fire can be quickly cooled. In addition, even if the coolant containing space is arranged obliquely, all the coolant in the coolant containing space can be supplied to the battery cell that has caught fire. It is possible to effectively suppress the thermal runaway phenomenon of the battery cell while minimizing the increase in the volume of the battery module and / or battery pack.

[0035] Furthermore, when the sealing member added to the cooling part is melted by the high temperature of the battery cell, the coolant is directly injected from the cooling part into the battery cell, so that the temperature of the battery cell can be quickly lowered. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 is a schematic diagram of a battery module or a battery pack according to an embodiment of the present disclosure;

[0037] Figure 2 is a vertical cross-sectional view of a battery module or a battery pack according to an embodiment of the present disclosure;

[0038] Figure 3 The battery cell is shown in the figure. Figure 2 cooling condition of the elastic member in the cooling portion;

[0039] Figure 4 Shown in Figure 2 The cooling unit further includes a pressing member;

[0040] Figure 5 is a vertical cross-sectional view of a battery module or a battery pack according to another embodiment of the present disclosure;

[0041] Figure 6 It can be applied to Figures 2 to 5 A plan view of an embodiment of a heat sink of a cooling unit;

[0042] Figure 7 yes Figure 2 A partial enlarged view of

[0043] Figure 8 is an enlarged vertical cross-sectional view of a battery module or a battery pack in which a sealing member is added to a heat dissipation plate having a groove formed therein;

[0044] Fig. 9 is a vertical sectional view of a state in which a sealing member is added to a heat sink plate having a groove formed therein;

[0045] Fig.10 Schematically illustrates a situation in which a plurality of battery cell stacks (battery cell module assemblies) according to an embodiment of the present disclosure are accommodated in a battery pack;

[0046] Fig.11 yes Fig.10 A vertical cross-sectional view of a battery pack according to an embodiment of the present disclosure, showing that a cooling unit is included in Fig.10 The situation of multiple battery cells stacked on the battery pack;

[0047] Fig.12 and Fig.13 is a vertical cross-sectional view of a battery module or a battery pack according to the prior art. DETAILED DESCRIPTION

[0048] Hereinafter, various embodiments of the present disclosure will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily implement the embodiments. The present disclosure can be modified in various different ways and is not limited to the embodiments set forth herein.

[0049] In addition, in the drawings, the size and thickness of each element are arbitrarily illustrated for the convenience of description, and the present disclosure is not necessarily limited to the contents illustrated in the drawings. In the drawings, the thickness of layers, regions, etc. are exaggerated for the sake of clarity. In the drawings, the thickness of components and regions are exaggerated for the convenience of description.

[0050] In addition, it will be understood that when an element such as a layer, film, region or plate is referred to as being "on" or "above" another element, it can be directly on the other element or there can also be intervening elements. Conversely, when an element is referred to as being "directly" "on" another element, it means that there are no other intervening elements. In addition, a portion located "on" or "above" a reference portion refers to a portion located above or below the reference portion, and does not specifically refer to a portion "on" or "above" facing the opposite direction of gravity.

[0051] In addition, throughout the specification, when a part is referred to as “including” or “comprising” a certain component, it means that the part may further include other components, without excluding the other components, unless otherwise specified.

[0052] In addition, throughout the specification, when referred to as a “plane”, it means when the target portion is viewed from the upper side, and when referred to as a “cross section”, it means when the target portion is viewed from the cross-sectional side cut vertically.

[0053] In addition, since the upper surface / lower surface or upper part / lower part of a specific component can be determined differently depending on the direction used as a reference, the "upper surface" and "lower surface" used in this article refer to two surfaces of the component facing each other on the z-axis, and the "upper part" and "lower part" are defined as being located in opposite directions on the z-axis of the corresponding component.

[0054] Figure 1 is a schematic diagram of a battery module or a battery pack according to an embodiment of the present disclosure.

[0055] The battery modules or battery packs within the meaning of the present disclosure differ only in scale, and are similar in that a cooling portion described in detail below is provided on at least one surface of the upper and lower portions of the battery cell stack.

[0056] Reference Figure 1 , a battery module or a battery pack 100 according to the present disclosure includes: a frame accommodating therein a battery cell stack 101 in which a plurality of battery cells are stacked; and cooling parts provided on upper and lower surfaces of the battery cell stack 101 .

[0057] As multiple battery cells, Figure 1, a bidirectional soft-pack battery cell in which the electrode leads 102 protrude in opposite directions to each other is shown, but unlike this, it is self-evident that a unidirectional soft-pack battery cell in which the cathode lead and the anode lead protrude in the same direction as each other may also be used. In addition, the battery cell may be a soft-pack type battery cell, but the present disclosure is not limited to the above, and various modifications and changes may be made, such as being applicable to a prismatic battery cell or a cylindrical battery cell.

[0058] The battery module or battery pack frame (hereinafter referred to as the “frame”) includes: an upper plate 110 disposed on the upper portion of the battery cell stack 101 ; a lower plate 120 disposed on the lower portion of the battery cell stack; and a side panel 130 disposed between the upper plate 110 and the lower plate 120 and disposed on the side of the battery cell stack 101 .

[0059] In addition, end plates (not shown) may be combined with the upper plate 110 , the lower plate 120 , and the side plates 130 at the outer side of the direction in which the electrode leads 102 of the battery cells protrude, thereby assembling the frame.

[0060] In addition, the shape of the frame is not limited to Figure 1 The structure shown in Figure 1 Different from the structure shown in , the frame can be in the form of a single frame or a U-shaped frame. That is, in some cases, the upper plate 110 may not be provided separately, and the upper surface of the cooling part to be described later may replace the upper plate of the frame.

[0061] Figure 2 is a vertical cross-sectional view of a battery module or a battery pack according to an embodiment of the present disclosure.

[0062] Reference Figure 2 , the battery module or the battery pack is configured such that a battery cell stack 101 in which a plurality of battery cells are stacked is accommodated in a frame including an upper plate 110 and a lower plate 120 .

[0063] The cooling part 200a includes a heat dissipation plate 210 and a coolant containing member 220 containing a coolant. The heat dissipation plate 210 is coupled to the upper plate 110 at a predetermined separation distance, and a space formed by the separation distance becomes the coolant containing member 220. Therefore, the upper plate 110, the heat dissipation plate 210, and the coolant containing member 220 form an integrated structure. The cooling part 200a is integrally coupled to the upper plate 110 and is located at the upper portion of the battery cell stack 101.

[0064] However, the present disclosure is not limited to the above. For example, in order to form the coolant containing member 220, the upper plate 110 of the frame does not necessarily need to be a component of the coolant containing member 220. It is not important whether the coolant containing member 220 itself has a shape capable of storing coolant, as long as the coolant containing member 220 has a shape and structure that is coupled to the battery cell stack 101 when the heat dissipation plate 210 including the through hole 230 described below is inserted between the coolant containing member 220 and the battery cell stack 101.

[0065] In addition, the cooling part 200a' includes a heat dissipation plate 210, and a coolant containing member 220 containing a coolant. The heat dissipation plate 210 is coupled to the lower plate 120 at a predetermined separation distance, and a space formed by the separation distance becomes the coolant containing member 220. Therefore, the lower plate 120, the heat dissipation plate 210, and the coolant containing member 220 form an integrated structure.

[0066] That is, the cooling portion 200a' is integrally combined with the lower plate 120 and is located at the lower portion of the battery cell stack 101. Similarly, the lower plate 120 of the frame does not necessarily have to form the coolant containing member 220. It is not important whether the coolant containing member 220 itself has a shape for storing coolant, as long as the coolant containing member 220 is a shape and structure that is combined to the battery cell stack with the heat dissipation plate 210 including a through hole 230 (described later) inserted between the coolant containing member 220 and the battery cell stack. The heat dissipation plate 210 is formed with a through hole 230, and a sealing member 240 is added to the through hole 230.

[0067] The sealing member 240 is made of a material that can be melted by high-temperature gas or sparks discharged from the battery cell. That is, when the battery cell is in a normal state, the sealing member 240 keeps the through hole 230 sealed, but when the temperature rises or a fire occurs like the battery cell 103, the sealing member 240 melts and the through hole 230 opens. The coolant in the coolant containing member is directly injected into the battery cell stack 101 through the open through hole 230. Through this process, the overheated or ignited battery cell can be quickly cooled, thereby quickly preventing the thermal runaway from expanding.

[0068] The sealing member 240 is a material that melts in the high-temperature gas discharged due to the exhaust of the battery cell whose temperature has increased or the sparks ejected. Therefore, a thermoplastic polymer resin having a melting point of about 200°C or less can be applied, and for example, as the thermoplastic polymer resin, a material having a melting point of about 100°C or more and 200°C or less, such as polyethylene or polypropylene, can be used.

[0069] On the other hand, in the case of applying cooling water as a coolant, considering that the coolant is directly injected into the battery cell, it is necessary to prevent the flame growth or explosion of the battery cell by the injection of cooling water. Therefore, preferably, the additive contained in the cooling water does not contain a flammable material. Alternatively, in the case of including a combustible material as an additive, the amount of the additive may be such that a secondary explosion of the battery cell can be prevented, and at the same time, such that it can be used as an antifreeze to prevent the cooling water from freezing.

[0070] On the other hand, the coolant containing member 220 has a structure (e.g., a water tank) in which the coolant is stored. More specifically, the cooling portion 200a according to the present disclosure includes a retractable / expandable elastic member 250 in the inner space of the coolant containing member 220, and contains the coolant in the elastic member 250. The space between the elastic member 250 and the coolant containing member 220 is an empty space and does not contain the coolant. Figure 2 The embodiment shows a case where the coolant is maximally accommodated in the elastic member 250 and the coolant expands maximally to cover the entire inner surface of the coolant accommodation member 220 .

[0071] The elastic member 250 is also made of a material that can be melted by the high-temperature gas or sparks discharged from the battery cell 101. In order to facilitate the melting of the elastic member 250 when the temperature of the battery cell 101 increases, the portion of the elastic member 250 adjacent to the through hole 230 of the heat dissipation plate 210 is formed to be relatively thinner than the other portions of the elastic member 250, or may be formed of a material having a lower melting point. When the temperature of the battery cell 101 rises, the sealing member 240 added to the through hole 230 of the heat dissipation plate 210 is melted by the high-temperature gas or sparks discharged from the battery cell 103 whose temperature has risen. Subsequently, the elastic member 250 is also opened by the high-temperature gas or sparks transmitted through the open through hole 230. Therefore, the coolant contained in the elastic member 250 is partially melted and supplied to the battery cell 103 through the open opening 255 and the open through hole 230.

[0072] like Figure 2 The elastic member 250, which is shown as being expanded to the greatest extent due to the internal pressure of the coolant, is configured so that as the coolant contained inside the elastic member 250 escapes, the pressure of the coolant pressing the elastic member 250 gradually decreases, and as shown in FIG. Figure 3 The elastic member 250 shown gradually contracts. Fig.12 and Fig.13, the coolant in the elastic member 250 located in the coolant containing member 220 can be supplied to the battery cell 103 at a faster rate due to the pressure caused by the contraction of the elastic member 250. In addition, the coolant existing in the elastic member 250 can be supplied to the battery cell 103 without any residue.

[0073] The elastic member 250 is made of a material that can be melted by the high-temperature gas or sparks discharged from the battery cell 101. The elastic member 250 is also a material that melts in the high-temperature gas or sparks discharged due to the exhaust of the battery cell whose temperature has risen, and is an elastic material that can shrink and expand. As the elastic member 250, for example, natural rubber, synthetic rubber (SBR), oil-resistant rubber (NBR), polyurethane rubber, etc. can be used. As an example, the elastic member 250 can have a rubber balloon shape.

[0074] On the other hand, when the elastic member 250 contracts, the elastic member 250 and the opening 255 of the elastic member 250 may move toward the upper plate 110 as the opposite side of the through hole 230 due to the reaction of the force causing the coolant to escape from the elastic member 250 .

[0075] In order to prevent this, an adhesive for adhering the elastic member 250 may be applied to the entire surface of the heat sink 210 facing the elastic member 250, or to the periphery of the through hole 230. The adhesive may not be an adhesive that permanently adheres the elastic member 250, but may be an adhesive of a composition that enables the elastic member 250 to be detached from the heat sink 210 as the elastic member 250 contracts. The adhesive may be, for example, an acrylic adhesive, a silicone adhesive, a rubber adhesive, or a hot melt adhesive. Alternatively, as Figure 4 As shown, a pressing member 260 having an elastic force may be provided between the inner surface of the cooling portion 200a and the outer surface of the elastic member 250. As an example, the pressing member 260 may be a spring. When the coolant is contained inside the elastic member 250, the elastic member 250 expands inside the cooling portion 200a due to the pressure caused by the coolant, so that the pressing member 260 is compressed. On the other hand, when the coolant is supplied to the battery cell 103 through the through hole 230 and the elastic member 250 gradually contracts, the pressing member 260 presses the outer surface of the elastic member 250 due to the restoring force of the compressed pressing member 260. As a result, the elastic member 250 may be in close contact with the periphery of the through hole 230.

[0076] The present disclosure is not limited to the above description and may be modified and changed in various ways, for example, one of the cooling part 200a located at the upper portion of the battery cell stack and the cooling part 200a′ located at the lower portion of the battery cell stack includes only the heat dissipation plate 210 and may not include the coolant containing member 220.

[0077] Figure 5 is a vertical cross-sectional view of a battery module or battery pack according to another embodiment of the present disclosure, which shows a Figure 2 The cooling unit 200a is a partially modified cooling unit 200b. Figure 5 The components of the cooling unit 200b are Figure 2 For a description of the components overlapping the cooling portion 200a, see Figure 2 Description.

[0078] exist Figure 5 In the embodiment of the present invention, the partition wall 215 may intersect the coolant containing member 220 in the vertical direction to define the internal space. For example, the partition wall 215 may have a structure that connects the heat dissipation plate 210 to the upper plate and to the side panel 130 (see Figure 1 ) are arranged in parallel in a plate shape. In this case, each battery cell of the battery cell stack 101 may be arranged in parallel with the length direction.

[0079] The coolant containing member 220 is divided into a plurality of regions arranged in a row in a lateral direction with respect to the partition wall 215. An elastic member 250 is provided in each of the plurality of regions defined in the coolant containing member 220, and the coolant is contained in each of the plurality of elastic members 250. When the temperature of the battery cell 103 rises or a fire occurs, the coolant may be supplied in divisions several times.

[0080] The number of partition walls 215 is not limited to Figure 5 The number shown in the figure may be one or more, and may be modified and changed in various ways, such as including a plurality of partition walls 250a to suit the environment in which the present invention is implemented.

[0081] The shape of the partition wall 215 is sufficient as long as it can partition and define the internal space of the coolant containing member 220, and does not necessarily have to be a flat planar shape, and various modifications and changes are possible. Figure 6 Is applicable to Figures 2 to 5 FIG. 2 is a plan view of an embodiment of a heat sink 210 of a cooling portion. Figure 6 (a) shows a state where the through hole 230 is formed in the heat dissipation plate 210 .

[0082] In the heat dissipation plate 210 , the through holes 230 formed in a planar circular shape are arranged to be spaced apart at regular intervals in the horizontal direction and the vertical direction.

[0083] A through hole must be formed at a position where cooling water can be supplied to a battery cell that has caught fire even when any battery cell catches fire. That is, preferably, at least one through hole is provided in each battery cell so that cooling water can be supplied to all battery cells. Therefore, the number and interval of the through holes can be adjusted according to the number and size of the battery cells.

[0084] Figure 6 (b) and Figure 6 (c) is Figure 6 (a) is a plan view of an embodiment in which the heat dissipation plate 210 is partially modified.

[0085] Reference Figure 6 (b) and Figure 6 (c), the shapes of the through holes 230' and 230" formed in the heat dissipation plate 210 are different from Figure 6 The shape of the through hole 230.

[0086] When the battery cells are arranged so that Figure 6 (b) and Figure 6 When the short axis direction of the heat dissipation plate 210 shown in (c) is parallel to the length direction (L) of the battery cell, the through hole 230' is formed obliquely so that one through hole can cover more than two battery cells, and the through hole 230" is formed in a direction perpendicular to the length direction (L) of the battery cell to cover more than two battery cells.

[0087] In the case of forming this type of through hole, if the sealing member is melted by the heating and explosion of one of the battery cells, the through hole is formed large. Therefore, cooling water can be added to the surface of the battery cell adjacent to the heated and exploded battery cell but not heated or exploded. Thus, by lowering the temperature of the battery cell that is not heated or exploded, the thermal runaway phenomenon can be prevented from occurring.

[0088] Figure 7 yes Figure 2 A space may be generated between the battery cell stack 101 and the heat dissipation plate 210, and a deviation in the distance between the battery cell and the heat dissipation plate 210 may occur for each individual battery cell. In this way, the space formed between the battery cell stack 101 and the heat dissipation plate 210 causes a decrease in heat dissipation performance for discharging heat inside the battery module and / or battery pack to the outside.

[0089] To prevent such problems, the space between the battery cell stack 101 and the heat sink 210 may be filled with a thermal interface material (TIM) 390 .

[0090] Since the thermal interface material 390 widens the thermal contact point between the battery cell stack and the heat sink, heat energy generated in the battery cell stack can be quickly discharged.

[0091] However, if the heat energy exhausted from the battery cell does not directly reach the sealing member due to the heat transfer material 390, the sealing member may not reach the melting temperature. Therefore, the addition of the thermal interface material may be omitted.

[0092] Alternatively, the thermal interface material is not formed at the lower portion of the through hole of the heat dissipation plate, and the thermal interface material may be in a shape that is only added to other portions. In such a case, even if the thermal interface material is added, the heat energy of the exhausted battery cell can be directly transferred to the sealing member without loss, so the sealing member melts and enables the coolant to be supplied to the exhausted battery cell.

[0093] On the other hand, the sealing member 240 is added to the through hole 230 penetrating the heat dissipation plate 210. For example, the sealing member 240 fills the through hole 230 and includes an extension 241 extending further outward from the periphery of the through hole 230 at the inner side 211 and the outer side 212 of the heat dissipation plate 210.

[0094] Since the extension part 241 is formed in the sealing member 240 , it is possible to prevent the sealing member 240 from being removed by the pressure of the cooling water flowing through the coolant containing member, thereby preventing the through hole from being opened.

[0095] Figure 8 is an enlarged vertical sectional view of a battery module or a battery pack in which a sealing member is added to a heat dissipation plate in which a groove is formed.

[0096] Reference Figure 8 , the coolant containing member 320 is formed between the upper plate 110 and the heat dissipation plate 310 , and the sealing member 340 is added to the through hole of the heat dissipation plate 310 .

[0097] The sealing member 340 includes an extension portion 341 , and a groove 314 is formed in a portion where the extension portion 341 is formed among the inner side surface 311 of the heat dissipation plate and the outer side surface 312 of the heat dissipation plate.

[0098] Since a portion of the sealing member constituting the extension portion 341 is inserted into the groove 314 to form the insertion portion 345 , it is possible to more effectively prevent the sealing member from being removed by the water pressure of the cooling water and prevent the through hole from being opened.

[0099] In order to manufacture a sealing member including an extension in this manner, an insert injection method can be used to introduce and manufacture a resin for the sealing member for a heat sink having a groove formed therein. Alternatively, for the portion of the sealing member that passes through the through hole, a central portion of the sealing member having a shape and size corresponding to the shape and size of the through hole can be prepared, and a separate member can be added to the central portion of the sealing member to form an extension. At this time, the method of combining the central portion of the sealing member with the separately added extension is not limited, such as adhesion, threaded fastening or press fitting using an adhesive material. In addition, the central portion of the sealing member is made of a thermoplastic polymer resin that melts at high temperatures, and the material of the separately added extension can be made of a material that does not melt at high temperatures.

[0100] Fig. 9 is a vertical sectional view of a state in which a sealing member is added to a heat dissipation plate in which a groove is formed.

[0101] Reference Fig. 9 , sealing members 440 , 540 , and 640 are added to the heat dissipation plates 410 , 510 , and 610 , respectively.

[0102] Each of the heat dissipation plates 410 , 510 , and 610 has grooves 414 , 514 , and 614 formed in portions where they meet the extensions, and insertion portions 445 , 545 , and 645 are formed inside the grooves 414 , 514 , and 614 .

[0103] A vertical cross section of a portion where the grooves 414, 514, and 614 are formed in the heat dissipation plates 410, 510, and 610 may be formed in one or more shapes selected from the group consisting of a polygon including a triangle, a trapezoid, etc., a semicircle, and may be formed by combining them.

[0104] Reference Fig. 9 In Fig. 9 (c) The thickness of the central portion 641 of the sealing member 640 is formed to be thinner than the thickness of the central portion of the sealing member 410 and the central portion of the sealing member 510. When the thickness of the portion sealing the through hole is formed to be relatively thin in this way, the time required for the sealing member to melt and the through hole to open can be shortened, so that the coolant can be quickly supplied to the battery cell.

[0105] In addition, the heat dissipation plate may constitute a water tank combined with the upper plate and the lower plate of the frame, and the heat dissipation plate may constitute the other surface facing one surface of the water tank combined with the upper plate and the lower plate.

[0106] The battery module or battery pack including one battery cell stack 101 and the cooling part included therein according to the present disclosure are described above mainly with reference to the accompanying drawings, but the cooling part according to the embodiments of the present disclosure can be similarly applied to a battery pack including multiple battery cell stacks (battery module assemblies) 101.

[0107] Will refer to Fig.10 and Fig.11 A case where a plurality of battery cell stacks (battery module assemblies) 101 are stacked to form a battery pack is described. Fig.10 A state in which a plurality of battery cell stacks 101 are accommodated in a battery pack 100 ′ according to an embodiment of the present disclosure is schematically illustrated. Fig.11 yes Fig.10 A vertical cross-sectional view of a battery pack according to an embodiment of the present disclosure, showing that a cooling unit 200 is included in Fig.10 The situation on the multiple battery cell stacks 101. Fig.10 and Fig.11 In the battery pack 100', a cooling unit 200 is shown as being placed on a plurality of battery cell stacks 101. Figures 1 to 9 The cooling portion described in can be similarly applied to a battery pack 100 ′ in which a plurality of battery cell stacks 101 are stacked.

[0108] Reference Fig.11 , the cooling unit 200 may be located on a plurality of battery cell stacks (battery module assemblies) 101 .

[0109] The frame includes an upper plate 110 disposed on the upper portion of the plurality of battery cell stacks 101, a lower plate 120 disposed on the lower portion of the plurality of battery cell stacks 101, and side panels (not shown) disposed between the upper plate 110 and the lower plate 120 and disposed on both sides of the plurality of battery cell stacks 101. In addition, a cross beam 140 may be included between the plurality of battery cell stacks 101. The shape of the frame including the upper plate 110, the lower plate 120, and the side panels is not limited to Fig.10 and Fig.11 The structures shown are shown and can be modified and changed in various ways to suit the environment in which the invention is implemented.

[0110] Reference Fig.11 The upper plate 110 and the lower plate 120 refer to the upper plate of the frame and the lower plate of the frame, respectively, and for convenience, are referred to as the upper plate 110 and the lower plate 120, respectively. This should be understood as a concept separate from the upper plate of the coolant containing member 220 and the lower plate of the coolant containing member 220 based on the coolant containing member 220.

[0111] exist Fig.11, the cooling unit 200 includes a coolant containing member 220 that contains a coolant. One surface of the coolant containing member 220 is disposed on at least one surface of the plurality of battery cell stacks 101. One surface of the coolant containing member 220 may be a heat dissipation plate 210. The other side facing the one surface of the coolant containing member 220 may be an upper plate 110 of the frame. That is, when the coolant containing member 220 is disposed on the upper portion of the plurality of battery cell stacks 101, the upper plate of the coolant containing member 220 may be an upper plate of the frame 110. The heat dissipation plate 210 includes a plurality of through holes 230. The through holes 230 are sealed with a sealing member 240.

[0112] On the other hand, the difference is that Fig.11 The coolant receiving member 220 of the battery pack 100 ′ is disposed on the plurality of battery cell stacks 101 , and Figure 2 The coolant containing member 220a of the battery module or battery pack 100 is provided on one battery cell stack 101, but Fig.11 Detailed components of the coolant containing member 220 and Figure 2 Detailed components of the coolant containing member 220 a of the battery module or battery pack 100 are the same.

[0113] Therefore, about Fig.11 The detailed components of the coolant containing member 220 are described with Figure 2 The detailed description of the coolant containing member 220a of the battery module or battery pack 100 overlaps. Therefore, for further explanation, reference is made to Figures 1 to 9 In addition, regarding Fig.11 The description of the part marked A in Figure 7 The parts explained in the above overlap, therefore, reference is made to the above contents in the relevant parts.

[0114] also, Fig.11 The cooling unit 200 is shown as being disposed on the plurality of battery cell stacks 101, but in some cases, various modifications and changes may be made, for example, the cooling unit 200 is disposed below the plurality of battery cell stacks 101. Of course, the partition wall 215 may also be applied to the above-mentioned Figure 5 The cooling unit 220 described in the embodiment of FIG.

[0115] In this way, when the battery module and / or battery pack according to the present disclosure and the cooling unit included therein are used, even if the battery cell catches fire, the battery cell can be quickly cooled. In addition, even if the coolant receiving space is arranged obliquely, all the coolant in the coolant receiving space can be supplied to the battery cell that has caught fire. The thermal runaway phenomenon of the battery cell can be effectively suppressed while minimizing the increase in the volume of the battery module and / or battery pack.

[0116] Those of ordinary skill in the art, using the disclosure provided herein, will appreciate that various applications and modifications can be made without departing from the spirit and scope of the present disclosure.

[0117] The present invention has been described in detail with reference to the preferred embodiments. However, it will be appreciated by those skilled in the art that the scope of the present disclosure is not limited thereto, and that various modifications and improvements may be made in these embodiments without departing from the principles and spirit of the present invention as defined by the appended claims and their equivalents.

[0118] [Explanation of Reference Numerals]

[0119] 101: Battery Cell Stack

[0120] 110: On the board

[0121] 120: Lower board

[0122] 130: Side panel

[0123] 200a, 200a', 200b, 200b': cooling part

[0124] 210, 310, 410, 510, 610: heat sink

[0125] 215: Partition wall

[0126] 220, 320: Coolant containing member

[0127] 230, 230', 230", 267, 267', 330: Through hole

[0128] 240, 268, 268', 340, 440, 540, 640: Sealing components

[0129] 250: Elastic member

[0130] 260: Pressing member

Claims

1. A battery pack comprising: A battery cell stack, wherein a plurality of battery cells are stacked in the battery cell stack; a frame that accommodates the battery cell stack; as well as a cooling unit, the cooling unit being arranged on the battery cell stack, Wherein, the cooling unit comprises: a coolant containing member, the coolant containing member comprising an upper plate and a lower plate; an elastic member disposed in an inner space of the coolant containing member; and a sealing member that seals at least one through hole formed in the coolant containing member and is meltable by a temperature increase of the battery cell, and The coolant is contained in the elastic member, and the elastic member expands as the coolant is contained.

2. The battery pack according to claim 1, wherein: Before the elastic member is melted, the coolant is contained in the elastic member, and the elastic member expands to the maximum extent and covers the entire surface of the inner space of the coolant containing member.

3. The battery pack according to claim 1, wherein: When the temperature of the battery cell increases, the sealing member is melted by high-temperature gas or sparks exhausted from the battery cell, and simultaneously or subsequently, a portion of the elastic member adjacent to the sealing member melts, causing the coolant within the elastic member to flow out to the battery cell stack.

4. The battery pack according to claim 3, wherein: While the coolant flows into the battery cell stack, the elastic member gradually contracts as the pressure of the coolant pressing the elastic member gradually decreases.

5. The battery pack according to claim 1, wherein: Coolant is not accommodated in a space between the coolant accommodation member and the elastic member.

6. The battery pack according to claim 1, wherein: An adhesive for adhering the elastic member is applied to a portion of the inner surface of the coolant containing member including the periphery of the through hole.

7. The battery pack according to claim 6, wherein: The adhesive is an acrylic adhesive, a silicone adhesive, a rubber adhesive or a hot melt adhesive.

8. The battery pack according to claim 1, wherein: The coolant containing member is a water tank, and cooling water is contained in the elastic member.

9. The battery pack according to claim 1, wherein: The battery pack includes at least one partition wall provided in the inner space of the coolant containing member to partition the inner space into a plurality of regions, The at least one partition wall is arranged perpendicular to the heat dissipation plate and along the length direction of the battery cell, and The elastic member is provided in each of the plurality of regions.

10. The battery pack according to claim 1, wherein: A pressing member having an elastic force is arranged between the inner surface of the cooling portion and the outer surface of the elastic member, When the coolant is contained in the elastic member, the pressing member is compressed due to the pressure caused by the coolant, and When the coolant is supplied to the battery cell through the through hole and the elastic member gradually contracts, the pressing member presses the outer surface of the elastic member due to a restoring force of the compressed pressing member so that the elastic member is in close contact with the periphery of the through hole.

11. The battery pack according to claim 10, wherein: The pressing member is a spring.

12. The battery pack according to claim 1, wherein: The sealing member is made of a thermoplastic polymer resin.

13. The battery pack according to claim 1, wherein: The elastic member is made of natural rubber, synthetic rubber (SBR), oil-resistant rubber (NBR) or polyurethane rubber.

14. The battery pack according to claim 1, wherein: A surface of the coolant containing member adjacent to the battery cell stack is a heat dissipation plate.

15. The battery pack according to claim 14, wherein: The framework includes: an upper plate disposed on an upper portion of the battery cell stack; A lower plate disposed at a lower portion of the battery cell stack; and A side panel is provided between the upper plate and the lower plate on the side of the battery cell stack, wherein the cooling unit is disposed on at least one of the upper plate and the lower plate, and Wherein, the heat dissipation plate of the coolant containing member is spaced apart from the frame by a predetermined distance to form the coolant containing member.

16. The battery pack according to claim 1, wherein: The battery cell stack is provided in plurality, and The cooling unit is provided on the plurality of battery cell stacks.

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