Nanowires in composite solid-state electrolytes: synthesis, structures and applications

Solid-state electrolytes (SSEs) are regarded as crucial materials, thus determining the comprehensive properties of solid-state lithium batteries (SSLBs). However, the existing issues of ion transport and interface limit their further development and application. As the inorganic solid-state electrolytes (ISEs) and polymer solid-state electrolytes (PSEs) both present obvious advantages and defects, the strategy of preparing composite solid-state electrolytes (CSEs) by incorporating inorganic components in polymer matrix is considered an effective way to overcome the above-mentioned problems. Nanowires with high aspect ratios are widely used in CSEs. Moreover, nanowires can not only effectively enhance the mechanical properties and ion transport efficiency of SSEs, but also boost the contact between electrolyte and electrode interface, thereby improving the cycle stability and safety of SSLBs. This review systematically categorized nanowires according to their morphology, function, and Li⁺ conductivity, and discussed their structural properties and synthesis strategies in detail. Moreover, application examples and mechanisms of nanowires in different polymer matrices are also introduced. In the summary and prospect section, we anticipate the existing challenges and future objectives of nanowires in the future research of CSEs.