New method developed to assess thermal runaway in lithium-ion batteries with high sensitivity
Battery safety assessment using a small battery, 1/50 the size of a conventional battery
(Source: University of Tokyo)
Ability to detect with high sensitivity various thermal phenomena occurring inside the battery up to thermal runaway
(Source: University of Tokyo)
A research team including the University of Tokyo and the National Institute for Materials Science (NIMS) has developed a new method that can quickly and cost-effectively detect the phenomenon of "high temperature rise", which can cause fires or explosions in lithium-ion batteries. It is hoped that this result will promote the development of safe, reliable, and high-performance storage batteries. The announcement was made on April 4.
An effective way to prevent thermal runaway in lithium-ion batteries. Establishing efficient and highly accurate safety assessment technology is essential, but conventional assessment methods are only aimed at product-sized batteries, making them difficult to apply at the basic research and development stage. These limitations are barriers to developing new materials to improve battery safety and optimize battery design efficiency.
The research team has now developed a simple and highly sensitive method to verify battery safety. We have demonstrated that thermal runaway behavior can be quantitatively analyzed using a small battery that is approximately 1/50 the size of a conventional battery and has a uniquely optimized shape to increase the sensitivity of thermal detection. This makes it possible to conduct safety assessment using extremely small amounts of raw materials, such as a few hundred milligrams of positive and negative electrode materials, and a few hundred microliters of electrolyte.
By making quantitative data collection much more efficient and simple, we can quickly and cost-effectively screen the impacts of many safety-related design factors (constituent materials and their inclusion ratios in the positive electrode, negative electrode, electrolyte, etc., battery shape, etc.) and usage conditions (temperature, storage conditions, number of charge/discharge cycles, whether to perform rapid charge/discharge, etc.).
The research results can be widely applied as a core technology for making batteries with highly guaranteed safety. In addition to the product development stage, the entire battery development process is expected to be significantly reduced in cost and speed by efficiently collecting and providing quantitative safety information during the discovery of new materials and the early design stage.
