氧调节原生负极-固态电解质界面层助力高稳定性固态钠金属电池

Oxygen-regulated spontaneous solid electrolyte interphase enabling ultra-stable solid-state Na metal batteries

Solid-state sodium metal batteries utilizing inorganic solid electrolytes(SEs)hold immense potentials such as intrinsical safety,high energy density,and environmental sustainability.However,the interfacial inhomogeneity/instability at the anode-SE interface usually triggers the penetration of sodium dendrites into the electrolyte,leading to short circuit and battery failure.Herein,confronting with the original nonuniform and high-resistance solid electrolyte interphase(SEI)at the Na-Na_(3)Zr_(2)Si_(2)PO_(12)interface,an oxygen-regulated SEI innovative approach is proposed to enhance the cycling stability of anode-SEs interface,through a spontaneous reaction between the metallic sodium(containing trace amounts of oxygen)and the Na_(3)Zr_(2)Si_(2)POi_(2)SE.The oxygen-regulated spontaneous SEI is thin,uniform,and kinetically stable to facilitate homogenous interfacial Na^+transportation,Benefitting from the optimized SEI,the assembled symmetric cell exhibits an ultra-stable sodium plating/stripping cycle for over 6600 h under a practical capacity of 3 mAh cm^(-2).Qua si-sol id-state batteries with Na_(3)V_(2)(PO_(4))_(3)cathode deliver excellent cyclability over 500 cycles at a rate of 0.5 C(1 C=117 mA cm^(-2))with a high capacity retention of95.4%.This oxygen-regulated SEI strategy may offer a potential avenue for the future development of high-energy-density solid-state metal batteries.