SIASSB · A complete solution for Si-based All-Solid-State Batteries by ensuring a long-term conductive environment and mitigating the strain mismatch between the electrode and the solid-state electrolyte

With higher energy density and better safety, all-solid-state batteries (ASSBs) are considered as an important direction for the next generation of lithium batteries, as well as part of the EU's battery program. The replacement of liquid electrolytes with solid electrolytes (SEs) has led to an unprecedented level of research on Li metal anodes. However, uneven deposition of Li-ions leads to lithium dendrites and interfacial gaps, which is an unavoidable electrochemical behavior and unavoidable. Silicon (Si) materials are underappreciated due to the large volume change during cycling. Nevertheless, Li-ions inserting and extracting within the Si-based electrode causes volume changes and a local separation from the SE, which is a mechanical behavior and prospectively avoidable. This proposal aims to provide a comprehensive solution for Si-based ASSBs that achieve stable long-cycle performance without excessive external stack pressure. Achieving this goal involves not only investigating SEs but also tackling issues such as low expansion Si-based materials, strain mismatch between the anode and SE, and managing complex interfaces. Specifically, the flexible conductive network in the anode electrode will provide some cushioning against volume changes of Si-based materials, and provide a long-lasting conductive environment for the electrode, which is an important guarantee for the long-term cycle of the battery. At the same time, a complex electrolyte with a certain degree of elasticity will mitigate the strain mismatch of thin-film bonding between the Si-based anodes electrode film and the SE film. The results of SIASSB provide a foundation for advancing the commercial viability of ASSBs. SIASSB will be expected not only to advance the scientific understanding of ASSBs but also to lay a solid foundation for enhancing their commercial viability.