Dual additives enabling high-performance solid polymer electrolytes for stable cycling of lithium metal batteries

CuF₂ and LiBOB were co-introduced into polycarbonate-based polymer electrolytes (PVT-CB) to overcome the trade-offs between ionic conduction and interfacial stability, resulting in improved ionic conductivity (8.4 × 10^-4 S cm^-1) and enhanced electrochemical stability (5.04 V vs. Li/Li⁺). The resultant Li|PVT-CB|LCO cells show a boosting capacity retention of 88.8% after 250 cycles. The combination of CuF₂ and LiBOB not only facilitates efficient Li⁺ transport but also enhances the stability of the electrolyte-electrode interface, making PVT-CB a promising candidate for high-performance, durable solid-state lithium metal batteries.