EP-4738547-A1 - THERMAL PROPAGATION PREVENTION BATTERY MODULE

Abstract

The present invention provides a structure of a battery module, comprising: a cell laminate comprising: a plurality of battery cells laminated in a widthwise direction; and a barrier member interposed therebetween; a housing comprising: a pack frame accommodating the cell laminate; and a cover covering an upper end of the pack frame; and a barrier receptor coupled to an inner surface of the cover the barrier receptor having a shape open in downward direction with an upper end of the barrier member inserted therein, wherein the barrier member and the barrier receptor are provided with overlapping sections of a predetermined length extending in upward direction and overlapping in widthwise direction, and the barrier member and the barrier receptor are slidable in upward direction while maintaining contact with each other.

Inventors

• LEE, Geumpyo
• CHOI, Wansup
• JUNG, Kitaek
• PARK, DONGHO
• HEO, Samhoe
• KIM, Jongjin
• Park, Jeongjae

Assignees

• LG Energy Solution, Ltd.

Dates

Publication Date

20260506

Application Date

20241031

Claims (18)

1. A battery module, comprising: a cell laminate comprising: a plurality of battery cells laminated in a widthwise direction; and a barrier member interposed therebetween; a housing comprising: a pack frame accommodating the cell laminate; and a cover covering an upper end of the pack frame; and a barrier receptor coupled to an inner surface of the cover the barrier receptor having a shape open in downward direction with an upper end of the barrier member inserted therein, wherein the barrier member and the barrier receptor are provided with overlapping sections of a predetermined length extending in upward direction and overlapping in widthwise direction, and the barrier member and the barrier receptor are slidable in upward direction while maintaining contact with each other.
2. The battery module of claim 1, wherein the barrier member comprises a heat-resistant material.
3. The battery module of claim 1, wherein the barrier member protrudes in upward direction with respect to the cell laminate.
4. The battery module of claim 1, wherein the barrier member comprises a compressible material.
5. The battery module of claim 4, wherein the barrier member comprises a compressible pad including the compressible material and a pair of rigid plates laminated at two widthwise ends of the compressible pad.
6. The battery module of claim 5, wherein the pair of rigid plates comprise a heat-resistant material.
7. The battery module of claim 1, wherein the barrier receptor comprises a pair of sidewall portions protruding in downward direction at two widthwise ends of the barrier member and extending in lengthwise direction.
8. The battery module of claim 7, wherein the pair of sidewall portions comprise a compressible material.
9. The battery module of claim 8, wherein each of the pair of sidewall portions comprises a compressible pad comprising a compressible material and a rigid plate comprising a heat-resistant material.
10. The battery module of claim 9, wherein a pair of rigid plates is provided at two widthwise ends of the compressible pad, respectively, in each of the pair of sidewall portions.
11. The battery module of claim 7, wherein the barrier receptor comprises a connecting part provided on the inner surface of the cover and connected to the pair of sidewall portions at two widthwise ends thereof, respectively, the connecting part comprising a flexible body deforming together with the cover as the cover is deformed.
12. The battery module of claim 1, wherein a tapered portion narrowing in upward direction is provided at an upper end of the barrier member.
13. The battery module of claim 1, wherein a tapered portion narrowing in downward direction is provided at the barrier receptor.
14. The battery module of claim 1, wherein the barrier member and the barrier receptor are provided in multiple pairs, and the overlapping section of a pair of the barrier member and the barrier receptor closer to a widthwise center is longer than that of a pair of the barrier member and the barrier receptor farther from the widthwise center.
15. The battery module of claim 1, wherein a length of the overlapping section is at least 1/2 of a distance between an upper surface of the cell laminate and the inner surface of the cover.
16. The battery module of claim 14, wherein among the multiple pairs of the barrier member and the barrier receptor, a length of the overlapping section of a pair of the barrier member and the barrier receptor closest to the widthwise center is at least 1/2 of a distance between an upper surface of the cell laminate and the inner surface of the cover.
17. A battery pack comprising a battery module of any one of claims 1 to 16.
18. A vehicle comprising a battery pack of claim 17.

Description

[TECHNICAL FIELD] This application claims the benefit of priority based on Korean Patent Application No. 10-2023-0149919 filed on November 2, 2023, entire content disclosed in the document of the patent applications is included as a part of this specification. The present invention relates to a structure of a battery module including a cell laminate with a plurality of pouch-type cells are stacked therein capable of preventing thermal runaway at the module level caused by thermal propagation between cells. [BACKGROUND ART] Secondary batteries, which provides ease of application depending on the product group and have electrical characteristics such as high energy density, are widely applied not only to portable devices, but also to electric vehicles or hybrid vehicles driven by an electrical driving source, and power storage devices. These secondary batteries are attracting attention as a new energy source for improving eco-friendliness and energy efficiency, not only because they have the primary advantage of being able to dramatically reduce the use of fossil fuels, but also because they do not generate any by-products due to energy use. While small mobile devices use one or two or three battery cells per device, medium to large devices such as vehicles require high output and large capacity. Therefore, a medium to large-sized battery module wherein multiple battery cells are electrically connected is used. Since it is desirable for medium to large-sized battery modules to be manufactured in as small and light as possible, rectangular batteries and pouch-type batteries that may be stacked with high integration and have a small weight-to-capacity battery are mainly used as battery cells for medium to large-sized battery modules. FIG. 1 illustrates a structure of a pouch-type battery cell. Referring to FIG. 1, a general pouch-type battery cell 11 has a structure wherein an electrode assembly 110 is accommodated in a pouch 111. The pouch 111 accommodates the electrode assembly 110 by folding and sealing a sheet in half and is fused and sealed at a sealed portion 111S on one heightwise end. A plurality of battery cell 11 may be laminated to form a cell laminate for higher voltage and/or a higher capacity. FIG. 2 illustrates the constitution of a cell laminate. Referring to FIG. 2, a plurality of battery cells 11 may be laminated in a widthwise direction to form a cell laminate 1. The cell laminate 1 may also include a barrier member 12 interposed between the battery cells 11 to prevent thermal propagation between the battery cells 11. The battery cells 11 may integrated to form one or more cell banks 10 isolated by the barrier member 12. The cell laminate 1 may be electrically connected to form a single module. FIGS. 3 and 4 illustrate the structure of a general battery module. Referring to FIGS. 3 and 4, the battery module M may include a bus bar frame assembly 2 connected to the front portion of the cell laminate 1 to electrically connect the battery cells 11 to each other, and a housing 3 that accommodates the cell laminate 1. Meanwhile, thermal runaway may occur in the battery cell 11 due to a short circuit or shock. The high-temperature gas and flame generated during the thermal runaway may be discharged through the upper portion of the battery cell 11 as the fused portion of the sealed portion 111S melts. The gas and flame may transmit heat to other battery cells through the free space within the housing above the cell laminate. Accordingly, there is a risk that not only the battery cell 11 but also other battery cells may ignite in a chain reaction, resulting in thermal runaway at the module level. [DISCLOSURE] [TECHNICAL PROBLEM] In order to solve above-described problems of prior art, it is an object of the present invention to provide a structure of a battery module wherein thermal propagation between battery cells is delayed or prevented. Specifically, it is an object of the present invention to provide a structure of a battery module wherein thermal runaway at the module level is delayed or prevented by blocking thermal propagation between cells caused by high-temperature gas and flame discharged from battery cells. It is another object of the present invention to provide a structure of a battery module capable of maintaining thermal propagation prevention structure and insulation structure despite deformation caused by thermal runaway. It is yet another object of the present invention to provide a structure of a battery module that is resistant to structural deformation caused by assembly tolerance or swelling, and is easy to manufacture. The technical problems to be solved by the present invention are not limited to the objects described above, and other objects and advantages of the present invention that are not described may be understood through the following description and will be more clearly understood by the examples of the present invention. Additionally, it is apparent that the object