LG Chem has unveiled a groundbreaking temperature-responsive Safety Reinforced Layer (SRL) that aims to prevent thermal runaway, a leading cause of electric vehicle (EV) battery fires. The innovative material, developed in collaboration with POSTECH’s Department of Battery Science, acts like a “fuse” to block the reaction path during the early stages of overheating, providing a critical safety feature for lithium-ion batteries. The research findings were published in the September edition of Nature Communications, a prestigious scientific journal.
How It Works: A Microscopic Guardian Inside Batteries
The thermal runaway suppression material is a composite layer, just 1 micrometer thick—about 1/100th the thickness of a human hair—placed inside the battery cell between the cathode and the current collector. When temperatures rise between 90°C and 130°C, the material alters its molecular structure, sharply increasing its electrical resistance. This change acts as a barrier, suppressing current flow and preventing overheating from escalating into a fire. Notably, the material is reversible, allowing the resistance to return to normal once the battery cools down, thus resuming regular operations.
Enhanced Safety Performance in Real-World Tests
In rigorous testing, the new material demonstrated its effectiveness in preventing fires. During a penetration test on mobile LCO (Lithium Cobalt Oxide) batteries, none of the batteries equipped with the thermal runaway suppression layer caught fire, compared to only 16% of regular batteries that remained safe. In impact tests on NCM (Nickel Cobalt Manganese) batteries, used in EVs, 70% of batteries with the new material did not ignite at all, while flames in the remaining 30% were extinguished within seconds.
These results mark a significant advancement over earlier temperature-responsive materials, which often struggled with slower reaction times and diminished energy density.
Towards Safer and More Reliable EV Batteries
Lee Jong-gu, CTO of LG Chem, emphasized the practical potential of this innovation, stating, “This is a tangible research achievement that can be applied to mass production in a short period of time. We will enhance safety technologies so that customers can use electric vehicles with confidence, and further strengthen our competitiveness in the battery market.”
LG Chem’s Platform Technology R&D team has already completed safety verification for mobile batteries and plans to continue testing the material for large-capacity EV batteries throughout next year. The goal is to integrate this technology into mass production, providing a safer solution for next-generation electric vehicles.
A Step Forward in Battery Safety Innovation
This breakthrough builds on LG Chem’s extensive experience and proprietary material design. The development of the SRL material not only addresses a crucial challenge in the battery industry but also aligns with the company’s broader vision of improving EV safety standards. With more than 8,000 BMS-related patents and a history of innovation, LG Chem is poised to lead in battery safety and reliability, ensuring a more secure future for electric mobility.
The research paper, titled “Thermal Runaway Prevention through Scalable Fabrication of Safety Reinforced Layer in Practical Li-ion Batteries”, details the collaborative work led by In-taek Song, Senior Researcher at LG Chem, and Professor Minah Lee of POSTECH, with analysis support from LG Energy Solution.
