Catenaa, Wednesday, December 31, 2025-Researchers at Argonne National Laboratory and the University of Chicago have uncovered a previously overlooked mechanical failure in single-crystal lithium-ion battery cathodes, explaining capacity loss, reduced lifespan, and potential fire risks.
The study, published in Nature Nanotechnology, shows that reaction heterogeneity inside individual particles creates nanoscopic strains that cause cracking, a different mechanism from polycrystalline cathodes.
Single-crystal cathodes, designed to avoid grain boundary issues seen in polycrystals, were expected to improve durability.
However, experiments using synchrotron X-rays and high-resolution electron microscopy revealed that uneven reaction rates within single particles generate internal stresses, leading to cracking.
This degradation pathway affects energy storage efficiency and, in extreme cases, can contribute to thermal runaway.
The team also found that material composition plays a critical role. While cobalt traditionally worsened cracking in polycrystals, in single-crystal cathodes it actually improves longevity, whereas manganese contributes more to mechanical failure.
These insights highlight the need for tailored design strategies and alternative materials to optimize next-generation cathodes for electric vehicles and advanced battery technologies.
By mapping the relationship between composition, mechanical stress, and degradation, the research provides guidance for developing safer, longer-lasting battery materials.
Future work will focus on finding cost-effective substitutes that replicate cobalt’s protective effects.
The study was led by Jing Wang and involved collaboration across Argonne, UChicago PME, and industry partners, supported by the GRC program and the Energy Transition Network.
