Water-modulated electrolyte enables the development of advanced low-temperature Zn-ion batteries

1,3-Dioxolane/water (95 : 5, vol) is screened for 1 m Zn(BF 4 ) 2 electrolyte, which delivers robust low-temperature performance. Zn‖MgVO full cells operate at −30 °C with >90% capacity after 300 cycles at 1C and sustain >2000 cycles at 10C.