High-Performance Dual-Salt Plastic Crystal Electrolyte Enabled by Succinonitrile-Regulated Porous Polymer Host

Succinonitrile (SN)-based plastic crystal electrolytes (PCE) show great promise for solid-state lithium-metal batteries (LMBs) because of their outstanding electrochemical properties. However, limited by the low mechanical strength of SN, SN-based PCEs are difficult to act as an independent self-supporting electrolyte films, which seriously restricts their practical application. In this study, a SN-regulated poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) porous host is proposed via a facile phase separation method as a promising strategy for addressing this issue, which enables a high-performance dual-salt SN-based PCE (named as DPCE). The as-prepared host simultaneously provides homogeneous porous network and robust mechanical support, which is convenient to accommodate DPCE evenly and increases the strength of DPCE to restrict dendrites growth. As a result, with this efficient host, the Li symmetric cell assembled with DPCE shows superior long-term stability for >1200 h at a current density of 0.1 mA cm(-2). Moreover, the assembled Li|LiFePO4 cell delivers a high-capacity retention of 99.3% after 700 cycles under 2 C at room temperature, demonstrating the promising potential for developing high-performance solid-state LMBs.