Inter-module bus bar capable of delaying thermal runaway transition and battery pack including the same

Abstract

The present invention relates to an inter-module busbar capable of delaying a thermal runaway transition and a battery pack including the same, more particularly, to an inter-module busbar capable of delaying a thermal runaway transition, the inter-module busbar comprising: a metal plate for electrical connection; and a cover member surrounding a portion of the metal plate, the metal plate having one or more first through holes formed therein that penetrate the metal plate in a longitudinal direction; and a first plug member inserted into the first through holes.

Description

[Technical Field]

[0001] This application claims the benefit of priority based on Korean Patent Application No. 10-2022-0139104, filed October 26, 2022, and all contents disclosed in the Korean Patent Application are incorporated herein by reference.

[0002] The present invention relates to an inter-module bus bar capable of delaying thermal runaway transition and a battery pack including the same, and more particularly to an inter-module bus bar capable of delaying thermal runaway transition and a battery pack including the same, which can prevent fires caused by thermal runaway in battery cells housed in the battery pack and explosions due to high pressure and high temperature caused by the transfer of venting gas. [Background technology]

[0003] Recently, the demand for secondary batteries that can store electrical energy produced by the development of alternative energy sources due to air pollution caused by the use of fossil fuels and energy depletion has increased. Rechargeable secondary batteries are widely used in everyday life, such as in mobile devices, electric vehicles, and hybrid electric vehicles.

[0004] Secondary batteries are used as energy sources for various electronic devices that are essential in modern society, and the required capacity is increasing due to the increasing use and complexity of mobile devices and the development of electric vehicles, etc. To meet user demands, small devices are equipped with multiple battery cells, while automobiles and the like use battery modules in which multiple battery cells are electrically connected, or battery packs equipped with multiple such battery modules.

[0005] Meanwhile, battery cells housed in a battery module may generate fire and venting gas due to external impact, short circuit, overcurrent, etc., and such fire and venting gas may occur instantaneously, resulting in damage such as explosion due to high temperature and high pressure.

[0006] Fig. 1 is a perspective view showing a conventional flexible busbar assembly. As shown in Fig. 1, the conventional flexible busbar assembly includes a busbar 10 that electrically connects adjacent battery modules and a cover member 20 that surrounds the busbar 10.

[0007] A conventional flexible busbar assembly can be easily electrically connected to battery modules installed in a location with a complex path by forming the busbar into a desired shape by bending or deforming the necessary portions.

[0008] However, when a fire or venting gas occurs due to thermal runaway of a battery cell in a battery module, an explosion due to high pressure may occur because no means is provided to relieve the pressure increased by the venting gas.

[0009] Furthermore, if the cover member 20 melts due to high temperatures, fire and venting gas can travel through the gaps to all the adjacent battery modules, causing a thermal runaway transition phenomenon and further increasing the damage. [Prior art documents] [Patent documents]

[0010] [Patent Document 1] Korean Patent Publication No. 10-2015-0101154 Summary of the Invention [Problem to be solved by the invention]

[0011] In order to solve the above problems, an object of the present invention is to provide an inter-module bus bar and a battery pack including the same, which can guide the movement of venting gas caused by a fire in a battery cell to a nearby space, thereby delaying and suppressing an explosion due to high pressure and delaying a thermal runaway transition.

[0012] Another object of the present invention is to provide an inter-module bus bar and a battery pack including the same, in which the cover member does not melt at high temperatures, thereby preventing the cover member from melting due to high temperatures caused by thermal runaway and spreading of fire and thermal runaway to the entire interior of the battery pack. [Means for solving the problem]

[0013] To achieve the above object, the intermodule busbar according to the present invention includes a metal plate (100) for electrical connection and a cover member (200) surrounding a portion of the metal plate (100), wherein the metal plate (100) has one or more first through holes (110) formed therein that penetrate the metal plate (100) in the longitudinal direction, and a first plug member (300) is inserted into the first through hole (110).

[0014] In the intermodule busbar according to the present invention, the first plug member (300) is made of a thermoplastic material.

[0015] In the intermodule busbar according to the present invention, the thermoplastic material includes at least one material selected from the group consisting of silicon, polyethylene, polypropylene, polystyrene, and polyvinyl chloride.

[0016] In addition, in the inter-module busbar according to the present invention, the cover member (200) is formed with a second through hole (210) through which the metal plate (100) passes in the longitudinal direction, and one or more third through holes (220) positioned at a distance from the second through hole (210), and a second plug member (400) is inserted into the third through hole (220).

[0017] In the intermodule busbar according to the present invention, the second plug member (400) is made of a thermoplastic material.

[0018] In the intermodule busbar according to the present invention, the thermoplastic material includes at least one material selected from the group consisting of silicon, polyethylene, polypropylene, polystyrene, and polyvinyl chloride.

[0019] In the inter-module busbar according to the present invention, the metal plate (100) is characterized by comprising an upper metal plate (120) and a lower metal plate (130) cut horizontally.

[0020] In the inter-module busbar according to the present invention, the length of the first plug member (300) is less than half the length of the first through hole (110).

[0021] In the inter-module bus bar according to the present invention, two or more first plug members (300) are inserted into the first through-hole (110).

[0022] In addition, in the intermodule busbar according to the present invention, the cover member (200) is characterized by including one or more materials selected from the group consisting of highly heat-resistant silicone, polyphenylene sulfide, polyether ether ketone, polyphthalamide, polyamide, polysulfone, polyethersulfone, polyetherimide, acrylic fiber, and polybenzimidazole.

[0023] The present invention may also be a battery pack including an inter-module bus bar having the above-described features. [Effects of the Invention]

[0024] As described above, in the case of a fire or venting gas occurring in a battery cell, the inter-module busbar according to the present invention has the advantage of being able to induce the movement of the venting gas by melting the plug member and opening the through-hole, thereby suppressing an explosion due to thermal runaway transition and high pressure generation.

[0025] Furthermore, the inter-module bus bar according to the present invention has an advantage in that the cover member does not melt at high temperatures, so that it is possible to prevent thermal runaway from spreading throughout the interior of the battery pack due to fire or the leakage of venting gas. [Brief explanation of the drawings]

[0026] [Figure 1] FIG. 1 is a perspective view showing a flexible bus bar assembly according to the prior art. [Figure 2] 1 is a perspective view showing an inter-module bus bar according to a first preferred embodiment of the present invention. [Figure 3] 1 is an exploded perspective view showing an inter-module bus bar according to a first preferred embodiment of the present invention. [Figure 4] FIG. 3 is a plan view of the intermodule bus bar shown in FIG. 2 as seen from the front. [Figure 5] FIG. 10 is an exploded perspective view showing an inter-module bus bar according to a second preferred embodiment of the present invention. [Figure 6] FIG. 6 is a plan view of the intermodule bus bar shown in FIG. 5 as seen from the front. [Figure 7] FIG. 10 is an exploded perspective view showing an inter-module bus bar according to a third preferred embodiment of the present invention. [Figure 8] FIG. 8 is a plan view of the intermodule bus bar shown in FIG. 7 as seen from the front. [Figure 9] FIG. 10 is an exploded perspective view showing an inter-module bus bar according to a fourth preferred embodiment of the present invention. [Figure 10] FIG. 10 is a plan view of the intermodule bus bar shown in FIG. 9 as seen from the front. DETAILED DESCRIPTION OF THE INVENTION

[0027] Hereinafter, with reference to the accompanying drawings, a detailed description will be given of an embodiment of the present invention that will enable a person of ordinary skill in the art to easily carry out the present invention. However, in describing the operation principle of the preferred embodiment of the present invention in detail, detailed description of related well-known functions or configurations will be omitted if it is determined that such detailed description may unnecessarily obscure the gist of the present invention.

[0028] Furthermore, the same reference numerals are used throughout the drawings for parts having similar functions and actions. Throughout the specification, when a part is said to be connected to another part, this includes not only a direct connection but also an indirect connection via another element therebetween. Furthermore, unless otherwise specified, "including a certain element" does not mean that other elements are excluded, but that other elements may also be included.

[0029] Hereinafter, an inter-module bus bar capable of delaying thermal runaway transition and a battery pack including the same according to the present invention will be described with reference to the accompanying drawings.

[0030] FIG. 2 is a perspective view showing an intermodule busbar according to a first preferred embodiment of the present invention, FIG. 3 is an exploded perspective view showing an intermodule busbar according to the first preferred embodiment of the present invention, and FIG. 4 is a plan view of the intermodule busbar shown in FIG. 2 as seen from the front.

[0031] As shown in FIGS. 2 to 4, the intermodule bus bar according to the present invention may include a metal plate 100, a cover member 200, and a first plug member 300.

[0032] Both ends of the metal plate 100 are exposed to the outside of the cover member 200, and these exposed portions serve to electrically connect the battery modules disposed in the battery pack.

[0033] Therefore, the length of the metal plate 100 can be determined in consideration of the distance between the battery modules to be connected, and the width and thickness can be determined in consideration of the amount of current to be passed and the resistance.

[0034] In addition, the metal plate 100 can be bent at specific portions as needed to form various shapes, taking into consideration the positions of the connectors of the battery module.

[0035] The metal plate 100 may have one or more first through holes 110 formed therein, spaced apart from the edge of the metal plate 100 and passing through in the longitudinal direction.

[0036] Such first through-holes 110 can guide the movement of venting gas due to fire or thermal runaway in the battery cell, thereby advantageously preventing explosion due to high pressure caused by the instantaneous generation of a large amount of venting gas.

[0037] To explain in more detail, as an example, a battery pack may have a plurality of storage spaces formed by partitions, each of which accommodates a battery module, and an inter-module bus bar may penetrate the partitions to electrically connect adjacent battery modules among the accommodated battery modules.

[0038] Here, venting gas may be generated due to overcurrent and thermal runaway in a battery cell housed in a specific battery module among the plurality of battery modules, causing an increase in pressure in the space housing the battery module.

[0039] When the first plug member 300 inserted into the first through hole 110 melts due to high temperature or comes off due to pressure caused by this venting gas, opening the first through hole 110, the venting gas moves along the first through hole 110 to the adjacent storage space, thereby alleviating the pressure increase in the storage space where the venting gas is generated, thereby preventing an explosion due to high pressure.

[0040] The cover member 200 is intended to maintain an insulating state of the surrounded portion of the metal plate 100 by surrounding the metal plate 100 except for both end portions, and may be made of an insulating material.

[0041] Furthermore, the cover member 200 is made of a material that does not melt at high temperatures such as fires and venting gases generated by thermal runaway, and may include, for example, one or more materials selected from the group consisting of highly heat-resistant silicone, polyphenylene sulfide, polyether ether ketone, polyphthalamide, polyamide, polysulfone, polyethersulfone, polyetherimide, acrylic fiber, and polybenzimidazole.

[0042] Here, high heat-resistant silicon exhibits the same performance as commonly used silicon at room temperature, but at high temperatures it transforms into a ceramic structure and acquires ceramic properties, thereby providing impact resistance while maintaining a certain strength.

[0043] Therefore, the cover member 200 can maintain its shape without being damaged or broken at high temperatures, and can maintain the insulating state of the metal plate 100, which has the advantage of preventing short circuits caused by contact between the metal plate 100 and nearby metal materials.

[0044] The cover member 200 has a second through-hole 210 formed in the vicinity of the center thereof, penetrating in the longitudinal direction, and the metal plate 100 may be inserted and positioned in the second through-hole 210 .

[0045] Here, the metal plate 100 may be positioned such that both ends are exposed to the outside of the cover member 200 .

[0046] The first plug member 300 has a long rod shape, is inserted into the first through-hole 110 of the metal plate 100, and may be made of a thermoplastic material.

[0047] The first plug member 300 may be formed in the same shape as the first through-hole 110 .

[0048] The thermoplastic material forming the first plug member 300 may include, for example, one or more selected from the group consisting of silicone, polyethylene, polypropylene, polystyrene, and polyvinyl chloride.

[0049] Therefore, the first plug member 300 normally blocks the first through-hole 110, preventing air from moving through the first through-hole 110 to the space where the nearby battery module is located. However, when the first plug member 300 melts and disappears due to high-temperature fire and venting gas, the venting gas moves through the first through-hole 110.

[0050] Here, the first plug member 300 maintains its shape when conditions such as high temperature and high pressure are not met, which has the advantage of preventing fire and venting gas from moving more than necessary into the space where nearby battery modules are located.

[0051] FIG. 5 is an exploded perspective view showing an inter-module bus bar according to a second preferred embodiment of the present invention, and FIG. 6 is a plan view of the inter-module bus bar shown in FIG. 5 as seen from the front.

[0052] Referring to Figures 5 and 6, the intermodule busbar according to the preferred second embodiment of the present invention is similar to the intermodule busbar according to the first embodiment described in Figures 2 to 4, except for the shape of the cover member 200 and the fact that it further includes a second plug member 400, and therefore a description of the same configuration will be omitted.

[0053] In the inter-module busbar according to the second embodiment of the present invention, the cover member 200 may have a third through hole 220 formed therein, spaced a certain distance from the second through hole 210 into which the metal plate 100 is inserted and passing through the cover member 200 in the longitudinal direction.

[0054] The third through-holes 220 can guide the movement of venting gas when venting gas is generated due to thermal runaway of the battery cell, thereby advantageously alleviating pressure caused by the venting gas.

[0055] A second plug member 400 having a long rod shape may be inserted and positioned in the third through-hole 220 .

[0056] The second plug member 400 is made of a thermoplastic material, and may include, for example, one or more selected from the group consisting of silicone, polyethylene, polypropylene, polystyrene, and polyvinyl chloride.

[0057] Therefore, the second plug member 400 normally blocks the third through-hole 220, thereby preventing air from moving through the third through-hole 220 to the space where the neighboring battery module is located. However, if the second plug member 400 melts and disappears due to high-temperature fire and venting gas, the venting gas will move through the third through-hole 220.

[0058] That is, the disappearance of the second plug member 400 causes the venting gas to move, which alleviates the pressure rise caused by the venting gas, thereby providing the advantage of being able to suppress explosions due to high pressure.

[0059] FIG. 7 is an exploded perspective view showing an inter-module bus bar according to a third preferred embodiment of the present invention, and FIG. 8 is a plan view of the inter-module bus bar shown in FIG. 7 as seen from the front.

[0060] Referring to Figures 7 and 8, the intermodule busbar according to the preferred third embodiment of the present invention is similar to the intermodule busbar according to the first embodiment described with reference to Figures 2 to 4, except for the shape of the metal plate 100, and therefore a description of the same configuration will be omitted.

[0061] The metal plate 100 according to the third embodiment of the present invention may be composed of an upper metal plate 120 and a lower metal plate 130 cut horizontally.

[0062] The metal plate 100 is formed into the upper metal plate 120 and the lower metal plate 130, and the first plug member 300 can be easily positioned in the first through hole 110 of the metal plate 100, which has the advantage of improving manufacturing efficiency.

[0063] FIG. 9 is an exploded perspective view showing an inter-module bus bar according to a fourth preferred embodiment of the present invention, and FIG. 10 is a plan view of the inter-module bus bar shown in FIG. 9 as seen from the front.

[0064] Referring to Figures 9 and 10, the intermodule busbar according to the preferred fourth embodiment of the present invention is similar to the intermodule busbar according to the first embodiment described in Figures 2 to 4, except for the shape of the first plug member 300, and therefore a description of the same configuration will be omitted.

[0065] The length of the first plug member 300 according to the fourth embodiment of the present invention may be less than half the length of the first through hole 110 .

[0066] Two or more first plug members 300 can be inserted into one first through-hole 110 .

[0067] Since a portion of the first through-hole 110 is formed where the first plug member 300 is not filled, manufacturing costs can be reduced, and since the first plug member 300 is pushed by high pressure and discharged to the outside of the first through-hole 110, the movement of venting gas can be induced, which has the advantage of further improving pressure adjustment performance against high pressure.

[0068] In addition, the second plug member 400 according to the second embodiment shown in Figures 6 and 7 is also formed to be less than half the length of the third through hole 220, similar to the first plug member 300 described above, and multiple second plug members 400 can be inserted and positioned in one third through hole 220.

[0069] The present invention also provides a battery pack including the inter-module bus bar, and may be a device equipped with the battery pack described above.

[0070] Those skilled in the art will be able to make various applications and modifications within the scope of the present invention based on the above content. [Explanation of symbols]

[0071] 100 Metal Plates 110 First Through Hole 120 Upper metal plate 130 Lower metal plate 200 Cover member 210 Second Through Hole 220 3rd Through Hole 300 First plug member 400 second plug member

Claims

1. a metal plate for electrical connection; a cover member surrounding a portion of the metal plate; Including, The metal plate has one or more first through holes formed therein, the first through holes passing through the metal plate in a longitudinal direction, a first plug member is inserted into the first through hole; When gas is generated in a battery cell, the first plug member melts or is released by pressure, allowing the gas to move along the first through hole.

2. The inter-module busbar of claim 1 , wherein the first plug member is made of a thermoplastic material.

3. The inter-module busbar of claim 2 , wherein the thermoplastic material comprises at least one selected from the group consisting of silicone, polyethylene, polypropylene, polystyrene, and polyvinyl chloride.

4. The cover member has a second through hole through which the metal plate passes in a longitudinal direction, and one or more third through holes spaced apart from the second through hole; The inter-module bus bar according to claim 1 , wherein a second plug member is inserted into the third through hole.

5. The inter-module busbar of claim 4 , wherein the second plug member is made of a thermoplastic material.

6. The inter-module busbar of claim 5 , wherein the thermoplastic material comprises one or more selected from the group consisting of silicone, polyethylene, polypropylene, polystyrene, and polyvinyl chloride.

7. The inter-module busbar according to claim 1 , wherein the metal plate comprises an upper end metal plate and a lower end metal plate cut horizontally.

8. The inter-module busbar according to claim 1 , wherein the length of the first plug member is less than half the length of the first through hole.

9. The inter-module busbar according to claim 8 , wherein two or more first plug members are inserted into the first through holes.

10. 2. The inter-module busbar according to claim 1, wherein the cover member comprises one or more selected from the group consisting of high heat resistant silicone, polyphenylene sulfide, polyether ether ketone, polyphthalamide, polyamide, polysulfone, polyethersulfone, polyetherimide, acrylic fiber, and polybenzimidazole.

11. A battery pack comprising the inter-module bus bar according to any one of claims 1 to 10.

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