Computational Design of an Affordable, Lightweight Solid Electrolyte for All-Solid-State Lithium-Ion Batteries

All-solid-state batteries (ASSBs) with nonflammable, lightweight, and inexpensive solid electrolytes (SEs) can potentially revolutionize lithium-ion battery (LiB) technology with superior miniaturization capability and safety standards. However, designing such affordable SE materials using traditional “trial-and-error” approaches is expensive, inefficient, and time-consuming, making it unsustainable in the current era of materials research. Thus, developing a design methodology that can significantly reduce resource and time consumption is desirable, albeit being challenging. The present work uses a combination of materials screening, first-principles density functional theory (DFT)-based calculations, and ab initio molecular dynamics (AIMD) simulations to design an SE material that meets the required design criteria. We predict Li14P2O3N6 or LiPON as a novel Li-ion SE material with all the required attributes. First-principles DFT calculations compute mechanical, electrochemical, and thermodynamic stability, electronic structure, and Li-ion diffusivity in the system. Climbing image nudged elastic band (cNEB) calculations show that LiPON exhibits a low Li-ion migration energy of 0.39 eV, which was corroborated by AIMD results. DFT and AIMD simulations predict room-temperature diffusivity of 5.4 × 10–10 and 6.35 × 10–11 cm2/s, while the Li-ion conductivity ranges from 10–4 to 10–5 S/cm, respectively.