KR-20260065273-A - BATTERY ASSEMBLY AND BATTERY PACK INCLUDING THE SAME

Abstract

A battery assembly according to one embodiment of the present invention comprises: a plurality of battery cells; and a cell frame in which the battery cells are housed. The cell frame comprises a bottom cell frame on which the battery cells are seated and a cover cell frame located on the bottom cell frame. A refrigerant circulates inside the cell frame while in direct contact with the battery cells. A groove is formed on the outer perimeter of the area of the bottom cell frame on which the battery cells are seated.

Inventors

• 정민용
• 최승빈
• 최범

Assignees

• 주식회사 엘지에너지솔루션

Dates

Publication Date

20260508

Application Date

20241101

Claims (15)

1. Multiple battery cells; and A cell frame in which the above battery cells are housed; and The cell frame comprises a bottom cell frame on which the battery cells are seated and a cover cell frame located on the bottom cell frame. The refrigerant comes into direct contact with the battery cells and circulates inside the cell frame, and A battery assembly having a groove formed on the outer perimeter of the area where the battery cells are seated in the bottom cell frame.
2. In paragraph 1, A waterproof adhesive is applied to the above bottom cell frame, and At least a portion of the above waterproof adhesive is a battery assembly located on the above groove.
3. In paragraph 1, A waterproof adhesive is applied to the above bottom cell frame, and At least a portion of the above waterproof adhesive is located between the bottom cell frame and the cover cell frame in a battery assembly.
4. In paragraph 1, A battery assembly in which the above cover cell frame is assembled into the groove of the above bottom cell frame.
5. In Paragraph 4, A waterproof adhesive is applied to the above bottom cell frame, and A battery assembly in which at least a portion of the above waterproof adhesive is applied to the portion where the cover cell frame is assembled to the groove of the bottom cell frame.
6. In paragraph 1, The above cover cell frame is a battery assembly comprising a rib that is engaged with the bottom cell frame.
7. In paragraph 6, The above rib is a battery assembly that engages with the above groove.
8. In Paragraph 7, A waterproof adhesive is applied to the above bottom cell frame, and A battery assembly in which at least a portion of the above waterproof adhesive is applied to the portion where the rib and the groove are joined.
9. In paragraph 6, The above rib is a battery assembly formed on the outer perimeter of the area where the battery cells are located in the cover cell frame.
10. In paragraph 1, The cell frame comprises a battery assembly including an inlet port through which the refrigerant flows into the cell frame and an outlet port through which the refrigerant is discharged to the outside of the cell frame.
11. In paragraph 1, The above battery cells are a battery assembly in which they are fitted inside the cell frame.
12. In paragraph 1, A battery assembly in which the bottom cell frame and the cover cell frame are joined by bolt members.
13. In paragraph 1, The above refrigerant is insulating oil or coolant in a battery assembly.
14. In paragraph 1, A battery assembly in which the above battery cells are housed in the cell frame and are mounted directly to a vehicle or chassis.
15. At least one battery assembly according to claim 1; A pack frame housing at least one of the above-mentioned battery assemblies and having one side open; and A battery pack comprising a pack cover covering an open side of the pack frame.

Description

Battery assembly and battery pack including the same The present invention relates to a battery assembly and a battery pack including the same, and more specifically, to an immersion cooling type battery assembly and a battery pack including the same. Secondary batteries, which have high applicability across product groups and electrical characteristics such as high energy density, are widely applied not only to portable devices but also to electric vehicles (EVs) or hybrid electric vehicles (HEVs) driven by electric power sources. These secondary batteries are widely used as an energy source for enhancing eco-friendliness and energy efficiency, not only because of the primary advantage of being able to drastically reduce the use of fossil fuels, but also because they do not generate any by-products from energy use. Types of secondary batteries include lithium-ion batteries, lithium-polymer batteries, nickel-cadmium batteries, nickel-hydrogen batteries, and nickel-zinc batteries. The operating voltage of these unit secondary battery cells, that is, unit battery cells, is approximately 2.5V to 4.5V. Therefore, if a higher output voltage is required, a battery pack may be formed by connecting multiple battery cells in series. Additionally, a battery pack may be formed by connecting multiple battery cells in parallel depending on the charge/discharge capacity required for the battery pack. Accordingly, the number of battery cells included in the battery pack can be set in various ways depending on the required output voltage or charge/discharge capacity. Meanwhile, when configuring a battery pack by connecting multiple battery cells in series or parallel, it is common to first form a battery module by creating a battery cell assembly containing multiple battery cells and housing it in a module case, and then configuring a battery pack by assembling one or more of these battery modules and adding other components, or by arranging multiple battery cells within a pack frame and adding other components. Since these battery cells consist of rechargeable secondary batteries, such high-output, high-capacity secondary batteries generate a significant amount of heat during the charging and discharging process. In this case, the heat emitted from multiple battery cells is aggregated within a confined space, causing the temperature to rise rapidly and severely. In other words, while battery packs containing multiple cells can achieve high output, it is not easy to dissipate the heat generated by the cells during charging and discharging. If heat dissipation from the battery cells is not properly carried out, the cells degrade rapidly, shortening their lifespan and increasing the risk of explosion or ignition. Furthermore, automotive battery packs are frequently exposed to direct sunlight and may be subjected to high-temperature conditions, such as during the summer or in desert regions. Additionally, because multiple battery cells are densely packed to extend a vehicle's driving range, flames or heat generated in a single battery cell can easily spread to neighboring cells, ultimately leading to the ignition or explosion of the battery pack itself. In conventional battery modules, bottom cooling or side cooling methods have been used, in which a heat sink is mounted on the module case of the battery module to cool it. However, in the case of battery modules using this cooling method, heat generated from the battery cells is transferred to a heat sink on one side of the module case for cooling, making it difficult to establish a heat transfer path to the other side of the module case. Consequently, there are limitations, such as intensified temperature differences between one end and the other of the battery cell assembly, or unsatisfactory overall cooling efficiency. If these temperature differences are not resolved, issues regarding the safety and durability of the battery module arise. Poor cooling efficiency can accelerate the degradation of battery cells or lead to the spread of thermal runaway if a rapid response is not possible when it occurs in some cells. This can result in disasters such as ignition and explosion of the battery module or the battery pack containing it, causing not only property damage but also safety issues. To solve this problem, it has been proposed to use a method of directly cooling the battery cells by filling the inside of the battery pack with coolant or insulating oil, rather than relying on bottom cooling or side cooling. That is, to effectively cool high-capacity battery packs, an immersion cooling method is used in which a refrigerant directly cools the battery cells inside the battery pack. However, implementing this immersion cooling method requires a stable waterproof structure. Since the refrigerant circulates within the battery pack, conventional immersion cooling methods employ various components, such as gaskets or waterproof foam tape, to create a waterproof structure. Because