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EP-4742398-A2 - BATTERY PACK AND VEHICLE INCLUDING THE SAME

EP4742398A2EP 4742398 A2EP4742398 A2EP 4742398A2EP-4742398-A2

Abstract

A battery pack according to an embodiment of the present disclosure includes a plurality of cell assemblies containing one or more battery cells and arranged in at least one row; a pack case configured to accommodate the plurality of cell assemblies; and a partition member configured to partition the plurality of cell assemblies within the pack case and made of flexible material to surround the plurality of cell assemblies in close contact.

Inventors

  • PARK, JEONG-HOON
  • KIM, SOO-YOUL
  • JANG, SUNG-HWAN

Assignees

  • LG Energy Solution, Ltd.

Dates

Publication Date
20260513
Application Date
20230707

Claims (13)

  1. A battery pack (10), comprising: a plurality of cell assemblies (100) containing one or more battery cells (110) and arranged in at least one row; a pack case (200) configured to accommodate the plurality of cell assemblies (100); and a partition member (300) configured to partition the plurality of cell assemblies (100) within the pack case (200) and made of flexible material, wherein the partition member (300) is in close contact with the plurality of cell assemblies (100), wherein the pack case (200) includes: a case body (210) including a bottom plate (212) and a side plate (218), and a case cover (230), wherein a venting portion (115) is provided at a lower portion of the one or more battery cells (110), and wherein the bottom plate (212) faces the venting portion (115) and is configured to open the inside of the pack case (200) by rupturing or melting to discharge the ejected matter, such as gas or flame, when said ejected matter is discharged through the venting portion (115).
  2. The battery pack (10) according to claim 1, wherein the bottom plate (212) is formed to have a thinner thickness than the side plate (218).
  3. The battery pack (10) according to claim 1, wherein the bottom plate (212) includes a venting unit that melts or ruptures as a separate member.
  4. The battery pack (10) according to any one of claims 1 to 3, wherein the side plate (218) is provided as a separate member from the bottom plate (212) and is coupled with the bottom plate (212) through bolting or bonding to form the case body (210).
  5. The battery pack (10, 50) according to any of claims 1 to 4, wherein the partition member (300) is in close contact with a side surface of the plurality of cell assemblies (100) in an arrangement direction of the plurality of cell assemblies (100).
  6. The battery pack (10, 50) according to any of claims 1 to 5, wherein the partition member (300) is placed between the plurality of cell assemblies (100) in an arrangement direction of the plurality of cell assemblies (100).
  7. The battery pack (10, 50) according to any of claims 1 to 6, wherein the partition member (300) is provided in plurality corresponding to the number of the plurality of cell assemblies (100), and wherein the plurality of partition members (300) are in close contact with both side surfaces of each cell assembly (100).
  8. A battery pack (50), comprising: a plurality of cell assemblies (100) containing one or more battery cells (110) and arranged in at least one row; a pack case (700) configured to accommodate the plurality of cell assemblies (100); and a plurality of partition member (300) configured to partition the plurality of cell assemblies (100) within the pack case (700) and made of flexible material, wherein each partition member (300) is in close contact with the plurality of cell assemblies (100), wherein the pack case (700) includes: a case body (710) including a bottom plate (712) and a side plate (718), a case cover (730), a guide channel (750), and a venting unit (770), wherein the bottom plate (712) includes a first plate (713) and a second plate (715), the first plate (713) and the second plate (715) being spaced apart from each other in the height direction of the pack case (700) to form the guide channel (750), wherein a venting portion (115) is provided at a lower portion of each battery cell (110), and wherein the first plate (713) faces the venting portion (115) of each battery cells (110) and is configured to rupture or melt to discharge the ejected matter, such as gas or flame, into the guide channel (750) when said ejected matter is discharged through the venting portion (115).
  9. The battery pack (10, 50) according to any of claims 1 to 8, wherein the partition member (300) is made of fire-resistant rubber material.
  10. The battery pack (10, 50) according to any of claims 1 to 9, wherein the partition member (300) is made of insulating rubber material.
  11. The battery pack (10, 50) according to any of claims 7 to 10, wherein the plurality of partition members (300) are arranged to be spaced from each other by a predetermined distance in an arrangement direction of the plurality of cell assemblies (100).
  12. The battery pack (10, 50) according to any of claims 1 to 11, wherein the partition member (300) surrounds side surfaces of the plurality of cell assemblies (100) while exposing the venting portion (115).
  13. A vehicle (1) comprising the battery pack (10, 50) according to any one of claims 1 to 12.

Description

TECHNICAL FIELD The present disclosure relates to a battery pack and a vehicle including the same, and more particularly, to a battery pack with improved safety against thermal events and a vehicle including the same. The present application claims priority to Korean Patent Application No. 10-2022-0183383 filed on December 23, 2022 in the Republic of Korea and Korean Patent Application No. 10-2023-0043172 filed on March 31, 2023 in the Republic of Korea, the disclosures of which are incorporated herein by reference. BACKGROUND ART Secondary batteries have high applicability according to product groups and electrical characteristics such as high energy density, and thus, are commonly applied not only to mobile devices but also to electric vehicles (EVs) or hybrid vehicles (HEVs) driven by electric power sources. Because secondary batteries may radically reduce the use of fossil fuel and do not generate any by-products that come with energy consumption, the secondary batteries are gaining attention as a new alternative energy source for improving eco-friendliness and energy efficiency. Types of secondary batteries that are currently widely used include lithium-ion batteries, lithium polymer batteries, nickel cadmium batteries, nickel hydride batteries, and nickel zinc batteries. An operating voltage of a unit secondary battery cell, that is, a unit battery cell, ranges from about 2.5 V to about 4.5 V. Accordingly, when a higher output voltage is required, a battery pack may be configured by connecting a plurality of battery cells in series. Also, a battery pack may be configured by connecting a plurality of battery cells in parallel according to charge/discharge capacity required for the battery pack. Accordingly, the number of battery cells included in a battery pack may be set in various ways according to a required output voltage or charge/discharge capacity. When a battery pack is configured by connecting a plurality of battery cells in series/parallel, a method of first configuring a battery module including at least one battery cell and adding other elements by using the at least one battery module to configure a battery pack or battery rack is general. However, if a plurality of secondary batteries (battery cells) or a plurality of battery modules are crowded in a small space as above, they may be vulnerable to thermal events. In particular, if an event such as thermal runaway occurs in one battery cell, high-temperature gas or flame, heat, etc. may be generated. If such gas, flame, heat, etc. is transferred to other battery cells included in the same battery module, an explosive chain reaction situation such as thermal propagation may occur. Also, this chain reaction not only causes accidents such as fire or explosion in the relevant battery module, but can also cause fire or explosion in other battery modules. Moreover, in the case of middle- or large-sized battery packs for electric vehicles, etc., a large number of battery cells and battery modules are included to increase output and/or capacity, so the risk of thermal chain reaction may increase further. In addition, in the case of a battery pack mounted on an electric vehicle, etc., there may be users such as drivers nearby. Therefore, if a thermal event occurring in a specific battery module is not properly controlled and a chain reaction occurs, it may cause not only significant property damage but also loss of life. Therefore, if thermal runaway due to a thermal event occurs on a battery module basis within the battery pack, it is important that such high-temperature gas or flame and ejected matter, such as particles, escapes from the battery pack more quickly to prevent greater risks such as secondary ignition or explosion due to an increase in the internal pressure of the battery pack. However, within the battery pack, mechanisms for accommodating the battery module or structures for partitioning different battery modules within the battery pack are made of aluminum to ensure rigidity, and most of them are melt at about 600°C. During a thermal event, the particles generated due to the melting of these structures collapse the mechanisms of the battery modules or the structures used to partition different battery modules within the battery pack, or increase the internal pressure of the battery pack by blocking the discharge portion of the venting unit of the battery pack, which becomes an important factor that can cause greater damage, such as secondary ignition or explosion of the battery pack as described above. In addition, in the case of a conventional battery pack, there is a problem that the collapse of the aforementioned mechanism or the structures such as venting unit may be accelerated due to the influx of ejected matter such as high-temperature gas, flame, or particles generated during a thermal event into a gap space generated by assembly tolerances between the mechanisms of the battery modules described above or the components cons