Superior Effect of Si Doping on Interfacial Reaction of LiPON Solid Electrolyte for the Silicon-Rich Oxide (SiO_1/2) Anode in All-Solid-State Batteries: A First-Principles Prediction

Abstract

Silicon oxide is considered an alternative silicon anode for lithium-ion batteries, possessing high lithium capacity and excellent cycling performance. However, the application of silicon oxide in a solid-state lithium battery is still not reported; exploring the atomic-scale mechanism at its interface with the solid-state electrolyte is critical for further study. In this work, atomic-scale electrochemistry of Si-, B-, and C-doped LiPON solid electrolytes for the silicon-rich oxide (SiO 1/2 ) electrode is explored by first-principles simulations. Our calculations reveal that the interfacial stability and conductivity are significantly enhanced upon doping of Si in LiPON. The SiO 1/2 /LiSiPON interface presents the highest adhesion energy and the lowest interface formation energy, suggesting a superior stability of the interface. An obvious shift of the DOS curve and large charge overlap area can be observed for LiSiPON with incorporation of the SiO 1/2 layer, which shows a much smaller band gap compared with primitive LiSiPON. Moreover, lithium tends to diffuse along the LiSiPON/ SiO 1/2 interface, and the doped elements provide a channel for lithium transport due to mutual electrostatic interaction. Our work provides theoretical guidance for designing electrode/SSE interfaces for silicon oxide-based ASSBs.

A comprehensive investigation of Ag7P3X11 (X = {O, S, and Se}) solid-state silver superionic conductors

“…[4][5][6] Although LIBs with liquid electrolytes provide excellent wetting capabilities and high conductivity, 7 they suffer from several drawbacks, including low ion selectivity, inadequate stability, and safety concerns. 8 Solid-state electrolytes (SSEs) address these issues, [9][10][11] enhancing safety, electrochemical and thermal stability, energy/power densities, and reducing packaging needs. [12][13][14] SSEs are generally categorized into inorganic ceramic electrolytes and organic polymeric electrolytes.…”