Search

JP-7857395-B2 - Gas venting device, battery module and battery pack including the same

JP7857395B2JP 7857395 B2JP7857395 B2JP 7857395B2JP-7857395-B2

Inventors

  • ド・スン・キム
  • イル・スク・シム
  • ヨン・チュル・チュ

Assignees

  • エルジー エナジー ソリューション リミテッド

Dates

Publication Date
20260512
Application Date
20230324
Priority Date
20220615

Claims (12)

  1. A hollow bracket member having a through hole, A discharge guide is inserted into the aforementioned through hole, and a gas discharge channel is formed through it. A venting disc is coupled to the bracket member to block the gas discharge passage and is configured to rupture when a predetermined pressure is applied, A gas venting device comprising, The aforementioned gas discharge channel is A first flow path in which the flow path cross-sectional area decreases continuously or sequentially along the gas discharge direction, A second flow path is formed continuously with the first flow path, and the flow path cross-sectional area increases continuously or sequentially along the gas discharge direction, Includes, The venting disc is installed on the inlet side of the gas discharge passage, The cross-sectional profiles on both sides of the first flow path are formed in a tapered shape that approaches each other in the direction of gas discharge. The cross-sectional profiles on both sides of the second flow path are formed in a tapered shape that moves away from each other in the direction of gas discharge. The venting disc is coupled to the bracket member and the discharge guide at the inlet side of the gas discharge passage of the discharge guide, thereby shielding the gas discharge passage . A gas venting device wherein a fastening portion for fastening the discharge guide to the bracket member is formed on the outer circumferential surface of the discharge guide, and the bracket member and the discharge guide are connected by a screw fastening method .
  2. The gas venting apparatus according to claim 1, wherein the first flow path and the second flow path are of the same or different lengths.
  3. The gas venting apparatus according to claim 1, wherein the tapered inclination of the first flow path and the tapered inclination of the second flow path are the same or different.
  4. The gas venting apparatus according to claim 1, wherein the cross-sectional profiles of both sides of the first and second flow channels are formed in a straight or curved tapered shape.
  5. The first channel has a first frustoconical shape in which the cross-sectional profiles on both sides are formed in a straight or curved tapered shape. The gas venting device according to claim 4, wherein the second flow path has a second frustoconical shape in which the cross-sectional profiles on both sides are formed in a straight or curved tapered shape.
  6. The first channel has a first truncated pyramidal shape in which the cross-sectional profiles on both sides are formed in a tapered shape. The gas venting device according to claim 1, wherein the second flow path has a second truncated pyramidal shape in which the cross-sectional profiles on both sides are tapered.
  7. The gas venting device according to claim 6, wherein the first and second truncated pyramidal shapes are truncated pyramidal shapes with a trapezoidal cross-sectional profile.
  8. The gas venting apparatus according to claim 1, wherein a flow channel having a straight cross-sectional profile on both sides is connected to the inlet side of the first flow channel.
  9. The aforementioned ventilation disk is The outer peripheral portion of the disk is coupled to the bracket member, The inner circumferential portion of the disk is formed integrally with the outer circumferential portion of the disk, which shields the gas discharge passage and ruptures when a predetermined pressure is applied, Includes, The gas venting device according to claim 1, wherein a notch is formed in the inner circumference of the disk so as to burst when the predetermined pressure is applied.
  10. Multiple rechargeable batteries, The module frame on which the secondary battery is mounted includes, A battery module in which a gas venting device according to any one of claims 1 to 9 is coupled to one side of the module frame.
  11. The battery module according to claim 10 , further comprising a sealing member for sealing the space between the module frame and the outer periphery of the gas venting device.
  12. A battery module comprising at least one secondary battery, The battery pack case on which the aforementioned battery module is mounted includes, A battery pack in which a gas venting device according to any one of claims 1 to 9 is coupled to one side of the battery pack case.

Description

This invention relates to a gas venting device for discharging gas from inside a battery module or battery pack. Furthermore, the present invention relates to a battery module and battery pack including the gas venting device described above. This application claims priority under Korean Patent Application No. 10-2022-0072872 dated June 15, 2022, and all content disclosed in the said Korean Patent Application is incorporated herein by reference. Battery packs used in electric vehicles and other applications have a structure in which multiple battery modules, each containing multiple secondary batteries, are connected in series or parallel to obtain high output. These secondary batteries include positive and negative electrode current collectors, separators, active materials, and electrolytes, and are capable of repeated charging and discharging through electrochemical reactions between their components. Rechargeable batteries can generate gas from within at any time during use, even during repeated charging and discharging cycles; this gas is called venting gas. For example, when an overcurrent flows, the internal temperature of the rechargeable battery rises rapidly. Such a rapid rise in temperature can trigger a decomposition reaction of the electrolyte, potentially generating gas. When gas is generated from within a rechargeable battery pack, this gas can either be trapped inside the pack, causing it to explode, or it can flow into the vehicle or other internal components via cooling ducts. Therefore, battery packs are equipped with venting devices to expel internal gas and reduce internal pressure. A venting device typically consists of a venting disc, which can rupture depending on the internal pressure, inserted between an inlet where gas from inside the battery module or battery pack enters and an outlet where the gas is discharged. Figure 1 is a perspective view showing an example of a conventional gas venting device, and Figure 2 is a schematic diagram showing the gas flow situation at the outlet of a conventional gas venting device. As illustrated, the conventional gas venting device 1 has the advantage of being easy to design because the gas discharge passage 11 of the bracket 10, which communicates with the venting disc 20, is simply designed in a cylindrical shape. However, conventional gas venting devices 1 have a simple cylindrical structure in which the gas inlet 12 and outlet 13 are connected. Therefore, the pressure between the inlet and outlet is not high enough, limiting the amount of gas that can be discharged. Furthermore, when a large amount of gas is generated, a so-called choking phenomenon may occur at the outlet of the gas discharge channel 11, causing flow stagnation and increasing flow instability. To avoid this choking phenomenon, the venting disc needs to be designed to rupture at low pressure. However, considering the rupture pressure tolerance, ensuring the reliability of the venting disc components can be difficult in this case. Furthermore, as illustrated in Figure 2, in a gas venting device with a cylindrical flow path 11, there is a problem in that unstable flow at the outlet and rapid pressure changes at the outlet generate a strong shock wave near the outlet, compromising safety. Furthermore, a localized pressure increase occurs downstream of the shock wave, leading to a problem where the outlet pressure rises again. This can result in a decrease in the pressure difference between the inlet and outlet, potentially reducing the discharge flow rate. Korean Published Patent No. 10-2018-0039986 This is a perspective view showing an example of a conventional gas venting device.This is a schematic diagram showing the gas flow conditions at the outlet of a conventional gas venting device.This is a drawing showing one embodiment of the gas venting device of the present invention.This is a schematic diagram showing the gas flow conditions at the outlet of the gas venting device of the present invention.This is a drawing showing the flow path shape of a gas venting device according to one embodiment of the present invention.This is a drawing showing the flow path shape of a gas venting device according to another embodiment of the present invention.This is a drawing showing the flow path shape of a gas venting device according to another embodiment of the present invention.This drawing shows a gas venting device according to another embodiment of the present invention.This is a drawing showing the fastening structure of the gas venting device of the present invention.Figure 9 is a perspective view of the gas venting device.This is a schematic diagram showing the shape of the venting disc according to the present invention.This is a schematic diagram showing the coupling structure of a gas venting device in a battery module according to one embodiment of the present invention. The gas venting device of the present invention comprises a hollow bracket member having a gas discharge