Review on Modeling for Chemo-mechanical Behavior at Interfaces of All-Solid-State Lithium-Ion Batteries and Beyond.

Abstract

The all-solid-state lithium-ion battery (ASSLIB) is a promising candidate for next-generation rechargeable batteries due to its high-energy density and potentially low risk of fire hazard compared with that of traditional lithium-ion batteries. However, the widespread application of ASSLIBs is unfortunately hindered by new critical issues arising from the all-solid-state structure, especially mechanical instability. First, employing solid electrolytes (SEs) in ASSLIBs is accompanied by a reduction of cell compliance. The SEs are normally much stiffer than liquid electrolytes, and they are no longer able to effectively accommodate the swelling and shrinkage of active particles during (de)lithiation. This may lead to the interfacial delamination and fragmentation of the active particles and electrolytes. In addition, although SEs are expected to mechanically suppress the growth of lithium dendrites at the lithium metal (Li)/SE interface, lithium dendrites are still observed frequently in battery cells employing SEs even with high stiffness. Hence, comprehending these phenomena and providing solutions to these issues are crucial to promote the application of ASSLIBs. A number of theoretical models have been developed to investigate the chemo-mechanical behavior of ASSLIBs in recent decades. This mini-review aims to comprehensively review them, focusing on the mechanically informed modeling on two main topics: (1) lithium dendrite initiation at the Li/SE interface and propagation through SEs and (2) delamination and fragmentation within a composite electrode due to (de)lithiation of an active particle. With this mini-review, we want to supply a more nuanced understanding for chemo-mechanical behavior at different interfaces in ASSLIBs from a modeling perspective.