NU 2021-090
INVENTORS Mark Hersam* Norman Luu Jin-Myoung Lim
SHORT DESCRIPTION Graphene coating that improves the stability, life cycle, and efficiency of Li -ion battery at high voltage
ABSTRACT Northwestern researchers have developed a conformal, conductive graphene coating that can stabilize high-voltage Li-ion batteries by reducing mechanical and chemical degradation. Current battery coatings are prone to cracking and delamination at high-voltage operations. This causes causing major industry problems and especially with the growing need for Li-ion batteries that are stable and efficient in high-voltage applications such as electrical vehicles. This new graphene coating addressing this problem by promoting spatially uniform charge transfer reactions across the electrode surface decreasing battery degradation. Additionally, it maintains electrical contact throughout cycling at high voltage substantially improved cycle life and battery efficiencies. The graphene-coated powders act as a drop-in replacement for incumbent cathode powders, making this strategy immediately relevant for battery manufacturing. This new graphene coating is easily processable, based on low-cost carbon, and can be generally applied to enhance the electrochemical performance of most electrode material.
APPLICATIONS
ADVANTAGES
PUBLICATION Luu N, Lim J-M, ….Hersam M (2021) Elucidating and Mitigating High-Voltage Interfacial Chemomechanical Degradation of Nickel-Rich Lithium-Ion Battery Cathodes via Conformal Graphene Coating. ACS Appl. Energy Mater. 4 (10):11069–11079.
IP STATUS A US patent applications has been filed.
Nickel-rich cathode powders are conformally coated with graphene, which protects the cathode particles from electrolyte decomposition reactions and enables spatially uniform charge transfer reactions. The resulting reduction in chemomechanical degradation is comprehensively characterized and results in substantial improvements in high-voltage cycle life and coulombic efficiency.