Work

Si–Ge alloys as promising anodes for sulfide-based solid-state batteries: Role of the powder morphology on performance

Year: 2025

Type: article

Abstract: As the demand for safe, high-energy energy storage devices grows with the energy transition, all-solid-state batteries (ASSBs) have become the central focus of research. This pioneering study explores Si0.5Ge0.5 alloys as negative electrode for sulfur-based ASSBs, and how the morphology and electrode formulation protocols influence their electrochemical performance. Two distinct morphologies of Si0.5Ge0.5 alloys were synthesized via ball-milling (BM) and laser pyrolysis (LP). Composite electrodes were prepared using two different protocols: densification and casting. The distribution of the composite electrode components was analyzed using SEM/EDX. Electrochemical performance was evaluated in half-cells using argyrodite as the solid electrolyte, through galvanostatic cycling, derivative analysis, and electrochemical impedance spectroscopy (EIS). Particularly, for the LP-cast composite electrode, a high specific capacity of 1580 mAh g-1am was achieved at C/5, with 86% capacity retention after 45 cycles. Additionally, the electrochemical behavior and performance of both BM and LP Si0.5Ge0.5 alloys were compared to those in a liquid electrolyte system with a classical electrode formulation, revealing similar (de)lithiation mechanisms to those in solid-state configuration.

Source: Journal of Energy Storage

DOI: 10.1016/j.est.2025.117912

Authors: A. Avila Cardenas, N. Herlin-Boime, L. Monconduit, C. Haon