Iek-Heng Chu just published a new article in ACS Applied Materials & Interfaces. This is a highly collaborative work involving the expertise of many MAVRL group members as well as the Meng group. In this work, we investigate the performance limits of Li7P3S11, a highly promising lithium superionic conductor solid electrolyte. We find that Li7P3S11 is metastable at 0 K but becomes stable at above 630 K (∼360°C) when vibrational entropy contributions are accounted for, in agreement with differential scanning calorimetry measurements. Both scanning electron microscopy and the calculated Wulff shape show that Li7P3S11 tends to form relatively isotropic crystals. In terms of electrochemical stability, first-principles calculations predict that, unlike the LiCoO2 cathode, the olivine LiFePO4 and spinel LiMn2O4 cathodes are likely to form stable passivation interfaces with the Li7P3S11 SCE. This finding underscores the importance of considering multicomponent integration in developing an all-solid-state architecture. We also find that the AIMD-predicted room-temperature Li+ conductivity of 57 mS/cm is much higher than the experimental values suggesting the potential for further optimization.
Professor Ong has been selected as one of the 2016 recipients for the ONR Young Investigator Program (YIP) Award. This award seeks to identify and support academic scientists and engineers who are in their first or second full-time tenure-track or tenure-track-equivalent academic appointment and who show exceptional promise for doing creative research. The program’s objectives are to attract outstanding faculty members to the Department of Navy’s research program, to support their research, and to encourage their teaching and research careers.
Paul Lin published his first-author paper on the “Thermodynamics, Kinetics and Structural Evolution of ε-LiVOPO4 over Multiple Lithium Intercalation”in Chemistry of Materials, as well as his co-author paper in ACS Applied Materials & Interfaces on “Thermal Stability and Reactivity of Cathode Materials for Li-Ion Batteries”. These papers are collaborative work as part of the NorthEast Center for Chemical Energy Storage and focuses on multi-electron rechargeable battery cathodes that have the potential to yield much higher energy densities than traditional single-electron chemistries.