Enabling high-performance all-solid-state hybrid-ion batteries with a PEO-based electrolyte.

All-solid-state hybrid-ion batteries exhibiting a synergistic Na+/Li+ de/intercalation mechanism were designed and assembled, by using modified PEO-based solid polymer electrolyte, Na2V2(PO4)2O2F cathode, and Li metal anode. The batteries exhibited a high average working voltage of 3.88 V, and an energy density of 432.37 W h kg-1, providing a new avenue for the development of high-safety and low-cost secondary batteries.