There is an increasing demand for high-performance and reliable energy storage technologies, especially lithium-ion batteries (LIBs), for many cutting-edge applications such as long-range electric vehicles and large-scale smart grids. Reliability and cyclability are among the most critical bottlenecks in the current LIBs technologies for these markets. In general, the compositional and structural instabilities of electrode materials are the most encountered problems responsible for the reliability issues. The state-of-the-art approach to improve the electrode stability is to protect the electrode surfaces using inhomogeneous coating layers. However, the internal resistance generated at the electrode/coating-layer interface has negative effects on performance. This project will investigate the controllable synthesis and electrochemical stability of FGM in LIBs for next-generation energy storage technologies. The project also includes related course development, undergraduate research experience and outreach plans to local high schools.
This project aims to understand the interfacial stabilization mechanism of lithium battery (LIB) electrodes through a controllable surface reconstruction and to establish experimental approaches for constructing functional graded materials (FGM) for durable LIBs. The project will use in-situ synchrotron X-ray characterization techniques to identify battery chemistry, coordination geometry, and phase transition behaviors in FGM coated electrodes. The project will comprehensively access the processing-structure-property relationship of FGM for LIBs by integrating advanced characterizations with electrochemical analyses. The research goals will be accomplished through the following objectives: (1) understanding the formation mechanism of structure/composition gradients in FGM by combining multiple in-situ and ex-situ electrochemical and spectroscopic characterization tools; (2) studying the roles of structure/composition gradient of FGM in improving the LIBs durability, understanding the effects of structure/composition gradients on the electrical and electrochemical properties of electrode materials; and (3) understanding the electrode protection mechanism of FGM, establishing approaches to probe the structural and compositional reconstruction of FGM for durable LIBs.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.