Silicon anodes and sulfide-based electrolytes (SEs) are considered to be one of the research foundations for all-solid-state batteries (ASSBs)

but their electrochemical and interfacial stabilities are still unclear. Herein

first-principles calculations combined with experiments are carried out to study the structural change characteristics of the silicon anode in the lithiation-delithiation cycle

and then predictive models are established for energy and volume changes of solid-state lithium batteries with Li3PS4 (LPS) and Li10GeP2S12 (LGPS) electrolytes during lithiation process. Moreover

the energy and structural changes of LPS with lithiated degradation at lithium and silicon anode interfaces are analyzed and the generation and propagation laws of interfacial cavities are investigated. The calculation results demonstrate that crystalline silicon transforms to an amorphous form after battery cycling

with an energy increase of 0.48 eV and a volume expansion of 21.9 Å3 per formula unit. The energy variation and the total cavity volume change of LPS with silicon anodes are only 30.1 eV and −0.4%

respectively

which are smaller than those with lithium anodes of 46.5 eV and 45.8%. The experimental results are consistent with the calculated predictions

suggesting that silicon anodes can effectively inhibit the spontaneous lithiated degradation of sulfide SSEs and suppress the formation of interfacial cavities. The experimental results indicate that the study of lithiation at interfaces of electrolyte and anodes provides references for safety issues

such as short circuits and thermal runaway of batteries.