Three Birds with One Stone: An Integrated Cathode-Electrolyte Structure for High-Performance Solid-State Lithium-Oxygen Batteries

Small. 2022 Apr;18(17):e2107833. doi: 10.1002/smll.202107833. Epub 2022 Mar 28.

Abstract

Constructing solid-state lithium-oxygen batteries (SSLOBs) holds a great promise to solve the safety and stability bottlenecks faced by lithium-oxygen batteries (LOBs) with volatile and flammable organic liquid electrolytes. However, the realization of high-performance SSLOBs is full of challenges due to the poor ionic conductivity of solid electrolytes, large interfacial resistance, and limited reaction sites of cathodes. Here, a flexible integrated cathode-electrolyte structure (ICES) is designed to enable the tight connection between the cathode and electrolyte through supporting them on a 3D SiO2 nanofibers (NFs) framework. The intimate cathode-electrolyte structure and the porous SiO2 NFs scaffold combination are favorable for decreasing interfacial resistance and increasing reaction sites. Moreover, the 3D SiO2 NFs framework can also behave as an efficient inorganic filler to enhance the ionic conductivity of the solid polymer electrolyte and its ability to inhibit lithium dendrite growth. As a result, the elaborately designed ICES can simultaneously tackle the issues that limit the performance liberation of SSLOBs, making the batteries deliver a high discharge capacity and a long lifetime of 145 cycles with a cycling capacity of 1000 mAh g-1 at 60 °C, much superior to coventional SSLOBs (50 cycles).

Keywords: SiO 2 nanofibers frameworks; composite solid electrolytes; integrated structures; solid-state lithium-oxygen batteries.