LG Chem promises to permanently save users from problems with overheating of lithium batteries. The graphite-based composite material developed by the company has the ability to change its molecular structure when heated, which completely makes it impossible for batteries to ignite in the event of a short circuit. This will change the world of batteries, the company is confident.
«A stake in the heart of a lithium battery is no longer a death sentence. Image Source: LG Chem
Traditionally, battery cathodes and anodes are covered with copper or aluminum foil to draw current from the electrodes. South Korean scientists have set themselves the goal of developing a non-metallic foil for current collectors, which would behave as an insulator when overheated. This would de-energize the cell and prevent the effects of a short circuit – the main cause of overheating and fire in lithium batteries.
During the scientific search, the researchers created a composite SRL (Safety Reinforced Layer) with inclusions of graphite (LiNi0.8Co0.1Mn0.1O2||graphite), which, when heated above a critical level for the battery, would increase its resistance. The material has demonstrated the ability to increase resistance by 5000 Ohms when heated for every degree Celsius. This broke the fatal chain leading to battery fire, as LG Chem demonstrated with pouch batteries for mobile devices.
Image source: Nature Communications, 2024
The proposed films of composite material with a thickness of only one micron are also one order of magnitude better at conducting heat than aluminum or copper foil. This helps the battery react faster to heat and can prevent it from overheating. The composite material replaces metal foil as a current collector, and its production is optimized for rolling production. At the same time, LG Chem is not yet ready for mass production of the new product and promises to continue improving this technology, also intending to demonstrate non-flammable car batteries based on it in 2025.