KR-20260068046-A - BATTERY PACK AND VEHICLE INCLUDING THE SAME

Abstract

A battery pack and an automobile including the same are disclosed. A battery pack according to one embodiment of the present invention comprises: a plurality of battery cells; a frame on which the plurality of battery cells are seated; a venting portion formed in a shape that closes the bottom surface of the plurality of battery cells and is at least partially opened by gas or heat; and a pack case in which the plurality of battery cells and the frame are housed. A protrusion extending downward is formed on the frame, and the bottom of the pack case and the protrusion of the frame come into contact, so that a flame exhaust space is formed between one of the protrusions and an adjacent protrusion. When a thermal event occurs in a battery cell, at least a portion of the venting portion is opened, allowing a flame to move through the venting portion to the flame exhaust space.

Inventors

• 정민용
• 최범
• 김인혁
• 정재헌

Assignees

• 주식회사 엘지에너지솔루션

Dates

Publication Date

20260513

Application Date

20260428

Claims (16)

1. Multiple battery cells; A frame on which the above plurality of battery cells are mounted; A venting portion formed in a manner that closes the bottom surface of the plurality of battery cells and is at least partially opened by gas or heat; and A pack case in which the plurality of battery cells and the frame are housed; comprising A protrusion extending downward is formed on the above frame, and The bottom of the pack case and the protrusion of the frame come into contact, so that a flame exhaust space is formed between one protrusion and an adjacent protrusion. A battery pack in which, when a thermal event occurs in the battery cell, at least a portion of the venting section is opened and the flame moves through the venting section to the flame discharge space.
2. In paragraph 1, A battery pack characterized by the venting portion being formed on the lower side of the frame.
3. In paragraph 1, A battery pack characterized in that the above frame includes a lower frame, and the above protrusion is formed on the lower frame.
4. In paragraph 3, The above protrusion is, A pair of first protrusions formed on each of the two edges of the lower frame; A second protrusion formed between the pair of first protrusions so as to be parallel to the pair of first protrusions; and A battery pack characterized by including a third protrusion formed to intersect the second protrusion.
5. In paragraph 3, The above battery cell is a cylindrical battery cell, and The lower frame has a seating portion having a circular cross-section formed therein so that the cylindrical battery cell is seated thereon, and A battery pack characterized by having the venting portion formed in the above-mentioned seating portion.
6. In paragraph 5, The above-mentioned seating portion is, A side lower support member supporting the lower side of the side of the above-mentioned cylindrical battery cell; and It includes a bottom support member that supports the bottom surface of the above-mentioned cylindrical battery cell, and A battery pack characterized by having a venting portion formed in the bottom support portion that breaks at a preset range of temperature or pressure.
7. In paragraph 6, When a thermal event occurs in the above cylindrical battery cell and the temperature or pressure exceeds a preset level, the above bottom support breaks, and A battery pack characterized in that the flame generated during the above thermal event moves through the fractured bottom support to the flame discharge space and is discharged.
8. In paragraph 6, A cooling fluid is contained inside the above frame, and A battery pack characterized by having a waterproof adhesive provided on the above-mentioned mounting portion to prevent leakage of the cooling fluid.
9. In paragraph 1, A battery pack characterized by having a cooling fluid contained within the frame and configured such that a plurality of battery cells are impregnated with the cooling fluid.
10. In Paragraph 9, A battery pack characterized in that the above cooling fluid includes cooling water or insulating oil.
11. In Paragraph 9, A battery pack characterized in that the above frame includes an intermediate frame and a lower frame, and the cooling fluid is received between the intermediate frame and the lower frame and comes into direct contact with the plurality of battery cells.
12. In Paragraph 11, A battery pack characterized by having a waterproof adhesive provided on the upper side of the intermediate frame to prevent leakage of the cooling fluid.
13. In Paragraph 12, A battery pack characterized in that the above-mentioned waterproof adhesive is an epoxy-based waterproof resin.
14. In Paragraph 13, A battery pack characterized in that the above-mentioned waterproof resin is made of a flame-retardant material.
15. In Paragraph 13, A battery pack characterized in that the above-mentioned waterproof resin is composed of a phase change material (PCM) and is arranged to cool the plurality of battery cells.
16. An automobile comprising a battery pack according to any one of paragraphs 1 through 15.

Description

Battery pack and vehicle including the same The present invention relates to a battery pack and a vehicle including the same, and more specifically, to a battery pack capable of preventing the propagation of flame or gas and a vehicle including the same. With the increasing technological development and demand for mobile devices, the demand for secondary batteries as an energy source is rapidly rising. While nickel-cadmium batteries or hydrogen-ion batteries were conventionally used as secondary batteries, lithium-ion batteries are now widely used because they exhibit almost no memory effect compared to nickel-based batteries, allowing for free charging and discharging, have a very low self-discharge rate, and high energy density. These lithium secondary batteries primarily use lithium-based oxides and carbon materials as the positive and negative active materials, respectively. The lithium secondary battery comprises an electrode assembly in which a positive plate and a negative plate, each coated with the positive and negative active materials, are arranged with a separator in between, and an outer casing, namely a battery case, that seals and houses the electrode assembly together with an electrolyte. Lithium secondary batteries consist of a positive electrode, a negative electrode, a separator interposed between them, and an electrolyte. Depending on the type of positive and negative active material used, they are classified into lithium-ion batteries (LIB), lithium-polymer batteries (PLIB), etc. Typically, the electrodes of these lithium secondary batteries can be formed by applying a positive or negative active material to a current collector, such as an aluminum or copper sheet, mesh, film, or foil, and then drying it. Lithium secondary batteries are currently in the spotlight due to their advantages, such as high operating voltage and significantly higher energy density, but because they use organic electrolytes, if the lithium secondary battery is overcharged, it causes overcurrent and overheating, which in severe cases can lead to explosions or fires caused by ignition. Various types of secondary batteries may include a battery module in which a plurality of battery cells are stacked and placed into a case equipped with a case capable of protecting the battery cells, and a battery pack in which a plurality of battery modules are stored. If a thermal event occurs in any battery cell equipped in a battery module and a flame occurs in at least one of the battery cells, the flame may spread to other battery cells where no flame occurred. As such, if a flame originating from any battery cell propagates to neighboring battery cells, a chain reaction of flames can cause damage, complete combustion, or explosion not only to the battery cells but also to the battery module or battery pack, posing a problem in that the stability of the battery module or battery pack cannot be ensured. Furthermore, since gas is generated from the battery cells within the battery module, various problems arise if this gas moves or is released in an unintended direction. Alternatively, if flames originating from a battery cell leak out of the battery module's casing, the fire can not only spread to other battery modules where no flames have occurred but also create a dangerous situation for the user. For example, if a fire originates in a battery cell while a battery module or battery pack is installed in an electric vehicle and leaks out, there is a risk that the driver of the vehicle may suffer burns or be put in a dangerous situation. The following drawings attached to this specification illustrate preferred embodiments of the present invention and serve to further enhance understanding of the technical concept of the present invention together with the detailed description of the invention provided below; therefore, the present invention should not be interpreted as being limited only to the matters described in such drawings. FIG. 1 is a schematic diagram showing a battery pack according to one embodiment of the present invention. FIG. 2 is a combined perspective view of a battery module provided in a battery pack according to one embodiment of the present invention. FIG. 3 is an exploded perspective view of a battery module provided in a battery pack according to one embodiment of the present invention. Figure 4 is a side view of the battery module of Figure 2 so that a protrusion is visible. Figure 5 is a drawing showing the bottom surface of Figure 2, showing a protrusion formed on the lower frame. FIG. 6 is a cross-sectional view of a battery module coupled to a lower case in a battery pack according to one embodiment of the present invention, which is schematically illustrated for the purpose of explanation. Figure 7 is a drawing illustrating the movement of flames as a fracture occurs in the bottom support of the lower frame in Figure 6. Figure 8 is an enlarged view of part A of Figure 3. Figure 9 is a drawing showi