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EP-3916900-B1 - GAS VENTING DEVICE AND BATTERY PACK COMPRISING SAME

EP3916900B1EP 3916900 B1EP3916900 B1EP 3916900B1EP-3916900-B1

Inventors

  • KIM, Doo Seung
  • SIM, IL SUK

Dates

Publication Date
20260506
Application Date
20210112

Claims (13)

  1. A gas venting device (100) for a battery module or a battery pack, the gas venting device (100) comprising: an inner bracket (110) including a first through hole in a central portion through which gas in a battery module or a battery pack flows in; an outer bracket (120, 220, 320) including a second through hole (121) in a central portion connected to the first through hole of the inner bracket (110) and including a flow path through which inflowing gas is discharged to an outside; and a venting disk (130) configured to shield the first through hole and the second through hole (121) by allowing the inner bracket (110) to be coupled to the outer bracket (120, 220, 320) and to be broken when a predetermined pressure is applied, wherein a cross-sectional area of a flow path formed at the outer bracket (120, 220, 320) continuously or sequentially is configured to decrease from an inlet portion (142, 242, 342) of the flow path to an outlet portion (143, 243, 343) of the flow path in a gas discharge direction, wherein a discharge guide member (140, 240, 340) including the flow path is formed in the second through hole (121) of the outer bracket (120, 220, 320), the discharge guide member (140, 240, 340) being connected to the second through hole (121), and wherein the flow path formed by the discharge guide member (140, 240, 340) has a truncated cone shape.
  2. The gas venting device (100) of claim 1, wherein the flow path formed by the discharge guide member (240) has a truncated cone shape in which the cross-sectional area of the flow path continuously decreases toward the outlet portion (243), an inclined surface formed on an inner wall (244) of the flow path is concavely bent.
  3. The gas venting device (100) of claim 1, wherein the flow path formed on the discharge guide member (340) has a truncated cone shape in which the cross-sectional area of the flow path continuously decreases toward the outlet portion (343), an inclined surface formed on an inner wall (344) of the flow path is convexedly bent.
  4. The gas venting device (100) of claim 2, wherein the cross-sectional area of the inlet portion (142, 242, 342) corresponds to the cross-sectional area of the first through hole formed on the inner bracket (110).
  5. The gas venting device (100) of claim 4, wherein the cross-sectional area of the outlet portion corresponds to 40 to 80% of the cross-sectional area of the inlet portion (142, 242, 342).
  6. The gas venting device (100) of claim 1, wherein a protrusion having a pattern of a screw thread, an embossing, or a straight line is formed at an inner wall (144, 244, 344) of the flow path.
  7. The gas venting device (100) of claim 1, wherein the venting disk (130) comprises: a disk outer periphery (131) configured to be coupled to the inner bracket (110) and the outer bracket (120, 220, 320); and a disk inner periphery (132) configured to be formed as one body with the disk outer periphery (131) and shield the through hole, and be broken when a predetermined pressure is applied.
  8. The gas venting device (100) of claim 7, wherein the disk inner periphery (132) is made of a metal or plastic material which is breakable when a predetermined pressure is applied.
  9. The gas venting device (100) of claim 7, wherein a notch (134) is formed on the disk inner periphery (132) to be broken when the predetermined pressure is applied.
  10. The gas venting device (100) of claim 1, wherein a disk pad is interposed between the outer bracket (120, 220, 320) and the venting disk (130) or between the inner bracket (110) and the venting disk (130).
  11. A battery module comprising: a plurality of secondary batteries; and a module frame having the secondary battery mounted thereon, wherein the gas venting device (100) according to claim 1 is formed at one side of the module frame.
  12. The battery module of claim 11, further comprising a sealing member configured to seal a part between the module frame and the outer periphery of the gas venting device (100).
  13. A battery pack comprising: a battery module configured to include a plurality of secondary batteries; and a battery pack case configured to include a tray having the battery module mounted thereon and a pack cover for covering the battery module, wherein the gas venting device (100) according to claim 1 is formed at one side of the battery pack case.

Description

[Technical Field] This application claims the benefit of priority based on Korean Patent Application No. 10-2020-0004772, filed on January 14, 2020. The present invention relates to a gas venting device, a battery module and a battery pack including the gas venting device, and a vehicle. [Background Art] DE 102013 210335 discloses a galvanic cell. The battery pack applied to an electric vehicle or the like has a structure in which a plurality of cell modules including a plurality of secondary batteries are connected in series or parallel to obtain high output. The secondary battery can be repeatedly charged and discharged by the electrochemical reaction between components including positive electrode and negative electrode current collectors, a separator, an active material, an electrolyte solution, and the like. KR 2016 0112766 discloses a positive electrode active material for a high voltage lithium secondary battery. In the secondary battery, as the charge/discharge is repeated, gas may be generated from the inside any time during use, which is called venting gas. For example, when an overcurrent flows, the temperature of the internal secondary battery rises rapidly. The rapid rise in such a temperature may cause a decomposition reaction of an electrolyte solution to generate gas. When gas is generated from the secondary battery inside the battery pack, such gas may be collected inside the pack, thereby exploding the battery pack, or flowing into a vehicle, etc. through a cooling duct, etc. of the battery pack. As such, a venting device for reducing the internal pressure by discharging inner gas to the outside is prepared in the battery pack. A venting disk, which may be broken according to the internal pressure between the inlet where gas inside the battery pack flows in and the outlet where gas is discharged, is generally inserted into the venting device. However, since the existing venting device has a cylindrical structure where the inlet portion and the outlet portion of the gas are simply connected, the pressure between the inlet and the outlet is not large, and thus there is a limit in the flow rate of dischargeable gas. [Disclosure] [Technical Problem] The present invention has been created to solve the above problems, and an object of the present invention is to provide a gas venting device capable of discharging gas at a higher flow rate with the venting disk of the same area, and a battery module and a battery pack including the same. [Technical Solution] A gas venting device for a battery module or a battery pack according to the present invention includes: an inner bracket including a first through hole in a central portion through which gas in a battery module or a battery pack flows in, an outer bracket including a second through hole in a central portion connected to the first through hole of the inner bracket and including a flow path through which inflowing gas is discharged to an outside; and a venting disk configured to shield the first through hole and the second through hole by allowing the inner bracket to be coupled to the outer bracket and to be broken when a predetermined pressure is applied, wherein a cross-sectional area of a flow path formed at the outer bracket continuously or sequentially is configured to decrease from an inlet portion of the flow path to an outlet portion of the flow path in a gas discharge direction. According to the present invention, a discharge guide member including the flow path is formed in the second through hole of the outer bracket, the discharge guide member being connected to the second through hole. According to the present invention, the flow path formed on the discharge guide member has a truncated cone shape. In another example, the flow path formed by the discharge guide member has a truncated cone shape in which the cross-sectional area of the flow path continuously decreases toward the outlet portion, an inclined surface formed on an inner wall of the flow path is concavely bent. In another example, the flow path formed by the discharge guide member has a truncated cone shape in which the cross-sectional area of the flow path continuously decreases toward the outlet portion, an inclined surface formed on an inner wall of the flow path is convexedly bent. In one specific example, the cross-sectional area of the inlet portion corresponds to the cross-sectional area of the first through hole formed on the inner bracket. In another specific example, the cross-sectional area of the outlet portion corresponds to 40 to 80% of the cross-sectional area of the inlet portion. In one example, a protrusion having a pattern of a screw thread, an embossing, or a straight line is formed at an inner wall of the flow path. In a specific example, the venting disk includes: a disk outer periphery configured to be coupled to the inner bracket and the outer bracket; and a disk inner periphery configured to be formed as one body with the disk outer periphery a