Design principles for multicomponent solid electrolytes for lithium metal anodes

The development of safe high energy density rechargeable lithium (Li) ion batteries is crucial for meeting the goal of clean sustainable energy. A major limiting factor in these batteries is the electrolyte – organic liquids are typically flammable and have limited electrochemical stability while most solid electrolytes have lower ionic conductivity and limited stability. Here, we focus on design principles for ionic transport in multicomponent solid electrolytes, either artificially created or naturally generated at the electrode-electrolyte interface. General tradeoffs prevent single component solid electrolytes from achieving the desired properties simultaneously [1] but may be broken through a multicomponent system by a careful use of the phase boundaries through the generation of space charge regions [2], confinement, ion adsorption etc. Together with the descriptors for ionic conduction, our design principles will be supplemented by theoretical spectroscopy studies based on x-ray absorption and emission to assist in experimental validation of samples with the required composition.

[1] Z. Ahmad, T. Xie, C. Maheshwari, J. C. Grossman, and V. Viswanathan, ACS Cent. Sci. 4, 996 (2018).
[2] J. Maier, Prog. Solid State Chem. 23, 171 (1995).