Ionic conductors have great potential for interesting tunable physical properties via ionic liquid gating and novel energy storage applications such as all-solid-state lithium batteries. In particular, low migration barriers and high hopping attempt frequency are the keys to achieve fast ion diffusion in solids. Taking advantage of the oxygen-vacancy channel in LixSr2Co2O5, we show that migration barriers of lithium ion are as small as 0.28~0.17eV depending on the lithium concentration rates. Our first-principles calculation also investigated hopping attempt frequency and concluded the room temperature ionic diffusivity and ion conductivity is high as 10−7∼10−6cm2s−1 and 10−3∼10−2S⋅cm−1 respectively, which outperform most of perovskite-type, garnet-type and sulfide Li-ion solid-state electrolytes. This work proves LixSr2Co2O5 as a promising super-ionic conductor.
@article{arxiv.2402.17557,
title = {Fast Lithium Ion Diffusion in Brownmillerite $\mathrm{Li}_{x}\mathrm{{Sr}_{2}{Co}_{2}{O}_{5}}$},
author = {Xin Chen and Xixiang Zhang and Jie-Xiang Yu and Jiadong Zang},
journal= {arXiv preprint arXiv:2402.17557},
year = {2024}
}