Uniform Na Metal Plating/Stripping Design for Highly Reversible Solid‐State Na Metal Batteries at Room Temperature
Runqing Miao, Chengzhi Wang, Donglai Li, Chen Sun, Jingbo Li, Haibo Jin
Abstract
Abstract Solid‐state alkaline metal batteries are highly sought out for their improved energy density and security over the current lithium‐ion batteries. However, their practical application is heavily hindered by the interfacial issues originating from the solid electrolyte/electrode mismatch. This work demonstrates that a CuO coating layer as an active interphase can thoroughly promote the intimate contact between a Na 3 Zr 2 Si 2 PO 12 solid electrolyte and a Na metal anode through an in situ conversion reaction. The resultant Cu/Na 2 O matrix forms a mixed electron/ion conducting scaffold, which facilitates stable and homogeneous Na metal plating without dendrite formation. Moreover, the symmetric Na metal cell realizes impressively steady plating/stripping cycles for 5000 h even under a high current density of 0.3 mA cm −2 . The novelty is further manifested as a room‐temperature solid‐state Na metal full battery of Na 3 V 1.5 Al 0.5 (PO 4 ) 3 |CuO@NZSPO|Na is assembled and exhibits a highly reversible cyclability (99.85% coulombic efficiency and 99.0% capacity retention) under a charge/discharge rate of 5 C for 2250 cycles. This work effectively solves the interfacial issues at the Na metal/solid electrolyte interface and provides a convenient way toward high‐performance solid‐state Na metal batteries operated at room temperature.