Reclaiming Neglected Compounds as Promising Solid State Electrolytes by Predicting Electrochemical Stability Window with Dynamically Determined Decomposition Pathway

Abstract The accurate prediction of the electrochemical stability windows (ESWs) enables the rational design of solid state electrolytes (SSEs). Currently, the ESW prediction is based on direct and indirect decomposition analysis methods (DDAM and IDAM). However, DDAM/IDAM can only involve thermodynamically/kinetically favorable decomposition pathway, both resulting in the large deviation between the predicted ESW and the experimental one. Specifically, certain excellent candidate SSEs may be continuously neglected in the high‐throughput screening due to underpredicted ESWs. Herein, a high‐accuracy ESW prediction method is proposed enabling dynamical determination of the appropriate decomposition pathway by analyzing the electronic conductivities of all direct and indirect decomposition products. Following this, a high‐throughput computation is performed on the ESWs of 328 possible fast Li‐ion conductors with low ionic migration energy barriers from the previous research, obtaining good agreement with the available experimental results (Li₁₀GeP₂S₁₂ and Li₇La₃Zr₂O₁₂). Furthermore, six previously neglected fluorides exhibiting ESWs over 4 V, oxidation potentials exceeding 6 V, excellent phase stability, and interfacial compatibility with seven typical cathodes are reclaimed as promising SSEs. This work demonstrates a strategy to accelerate the SSE development by improving the accuracy of the ESW prediction and enlarging the database of promising SSEs.