KR-20260062777-A - Early Detection Film for Battery Thermal Runaway

Abstract

The thermal runaway detection film according to the present invention comprises a fragrance layer comprising a fragrance substance that emits fragrance at 50°C or higher and a binder; and a substrate layer.

Inventors

• 심영석
• 정재한
• 조윤행

Assignees

• 한국기술교육대학교 산학협력단

Dates

Publication Date

20260507

Application Date

20250113

Priority Date

20241028

Claims (12)

1. A fragrance layer comprising a fragrance substance that emits fragrance at 50°C or higher and a binder; and A battery thermal runaway detection film capable of detecting a temperature rise in the early stages of battery thermal runaway, including a substrate layer.
2. In Article 1, A thermal runaway detection film characterized in that the above-mentioned fragrance substance is one or more of linalool, citral, eucalyptol, benzyl acetate, methyl salicylate, ethyl acetate, diethyl maleate, phenylethyl alcohol, hexanal, benzaldehyde, acetone, toluene, xylene, ethylbenzene, limonene, pine, and squalane.
3. In Article 1, A thermal runaway detection film characterized by the fragrance layer comprising 1 to 20 parts by weight of a fragrance substance per 100 parts by weight of the binder.
4. In Article 1, A thermal runaway detection film characterized by the above-mentioned scent layer having a thickness of 100 to 1000 μm.
5. In Article 1, A thermal runaway sensing film characterized by comprising one or more binders selected from polyester, polyimide, polyester acrylate, polysiloxane, epoxy resin, polyurethane, polyurethane acrylate, polysiloxane, and latex.
6. In Paragraph 5, A thermal runaway detection film characterized by the above binder being non-thermosetting.
7. In Article 1, A thermal runaway sensing film characterized in that the above substrate layer is one or more selected from polyethylene terephthalate, polycarbonate, polyimide, and polytetrafluoroethylene.
8. In Article 1, A thermal runaway detection film characterized by further including an adhesive layer that adheres to a battery cell.
9. In Article 1, A thermal runaway detection film characterized by the above-mentioned fragrance substance being distributed in a fragrance layer while encapsulated.
10. In Article 9, A thermal runaway detection film characterized by the above capsule being paraffin-based.
11. A battery comprising a thermal runaway detection film selected from any one of claims 1 to 10.
12. In Paragraph 11, A battery characterized by the above-mentioned thermal runaway detection film being interposed between cells.

Description

Early Detection Film for Battery Thermal Runaway The present invention was devised (conceived) as a result of the research on "Development of Smart Film & Sensor for Ammonia and Hydrogen Detection for Safe Eco-friendly Energy Source Utilization" of the Phase 3 Industry-Academic Cooperation Leading University Development Project (LINC 3.0), which was supported by funding from the Ministry of Education and the National Research Foundation of Korea. The objective of the present invention is to provide a film that detects a temperature rise before battery thermal runaway and emits a scent. Based on their excellent characteristics of high energy density, light weight, and long lifespan, lithium-ion batteries are currently one of the most widely used types of batteries. These lithium-ion batteries are used as energy storage devices in various fields, including electric vehicles (EVs), energy storage systems (ESS), home appliances, portable electronic devices, and medical devices. In particular, the demand for high-capacity lithium-ion batteries continues to increase with the expansion of electric vehicles and energy storage systems. However, lithium-ion batteries carry safety issues such as thermal runaway, and the risk of thermal runaway can be even greater in the case of high-capacity batteries. Most batteries, including lithium-ion batteries, are susceptible to thermal runaway due to various causes such as overcharging, over-discharging, external impact, internal short circuits, and temperature increases. When thermal runaway occurs, the protective layer between the negative electrode and the electrolyte decomposes, releasing gases, and the subsequent decomposition of the electrolyte can generate additional gases. If thermal runaway progresses further, the positive and negative electrode materials become activated, generating significant heat. This can lead to increased internal cell pressure due to gas generation, and if the condition persists, there is a risk of fire and explosion. Furthermore, thermal runaway can release toxic substances such as carbon monoxide, formaldehyde, and fluorine gas, and even if the runaway occurs in only a few cells, there is a risk of a chain reaction leading to explosions or fires. Moreover, in large-scale installation environments such as energy storage systems, thermal runaway in a single cell can affect the entire system. To address this thermal runaway problem, research and development have been conducted on small fire suppression devices that can be installed inside batteries; however, there is still a need to develop technology that warns of battery thermal runaway in the early stages, before the temperature rises rapidly during the process. Figure 1 illustrates the laminated structure of a thermal runaway detection film. Figure 2 is an exploded perspective view of a thermal runaway detection film interposed between battery cells. Figure 3 illustrates the laminated structure of a thermal runaway detection film when a fragrance substance is contained within a capsule. FIG. 4 illustrates a structure in which a thermal runaway detection film according to one embodiment of the present invention is attached to the outside of a battery pack. The advantages and features of the embodiments of the present invention, and the methods for achieving them, will become clear by referring to the embodiments described below in detail together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below but may be implemented in various different forms. These embodiments are provided merely to ensure that the disclosure of the present invention is complete and to fully inform those skilled in the art of the scope of the invention, and the present invention is defined only by the scope of the claims. Throughout the specification, the same reference numerals refer to the same components. In describing the embodiments of the present invention, specific descriptions of known functions or configurations will be omitted if it is determined that such detailed descriptions could unnecessarily obscure the essence of the invention. Furthermore, the terms described below are defined in consideration of their functions in the embodiments of the present invention, and these definitions may vary depending on the intentions or practices of the user or operator. Therefore, such definitions should be based on the content throughout this specification. The thermal runaway detection film according to the present invention is characterized by comprising: a fragrance layer comprising a fragrance substance that emits fragrance at 50°C or higher and a binder; and a substrate layer. The film according to the present invention is attached to a battery or a cell inside the battery, and when the temperature rises above 50°C at the beginning of thermal runaway, the fragrance substance spreads into the air to indicate the temperature rise, thereby enabling easy initi