Crystal structure of high-conduction §-Li3PS4 and scanning electron micrograph of its surface morphology
A nanoporous structure enhances the ionic conductivity of the solid electrolyte lithium thiophosphate by a factor of 1000 over its bulk value. Solid electrolytes may enable a much safer design of batteries by replacing the highly flammable liquid electrolytes in current technologies, as battery safety has become a critical concern in the development of lightweight lithium batteries with high energy densities for use in electric vehicles and aircrafts. Unfortunately, solid electrolytes exhibit a typically low ionic conductivity compared to that of the commonly used liquid electrolytes. This work shows that a nanoporous structure significantly boosts the ionic conductivity of lithium thiophosphate (Li3PS4). The nanoporous structure stabilizes the meta-stable β-Li3PS4 and promotes surface conduction, thereby enhancing the ionic conductivity by three orders of magnitude over bulk Li3PS4. Such a solid electrolyte enables the safe cycling of metallic lithium batteries, and the use of metallic lithium anodes would greatly enhance the energy stored in a battery (by a factor of five by volume, and factor of 10 by weight).
For more information, please contact Chengdu Liang, liangcn@ornl.gov
Zengcai Liu, Wujun Fu, E. Andrew Payzant, Xiang Yu, Zili Wu, Nancy J. Dudney, Jim Kiggans, Kunlun Hong, Adam J. Rondinone, and Chengdu Liang, “Anomalous high ionic conductivity of nanoporous β-Li3PS4,” Journal of the American Chemical Society, http://dx.doi.org/10.1021/ja3110895