Fig. 5: Asymmetric and symmetric cell performances.

a Coulombic efficiencies of Na plating/stripping on different collectors at current densities of 3 mA cm⁻² and areal capacities of 1 mAh cm⁻² and the magnified view of selected cycle numbers between 2000th and 4000th cycle for the Na | | HPJH-AlSi (Inset). b Voltage-capacity profiles of HPJH-AlSi at 3 mA cm⁻² and 1 mAh cm⁻². c Voltage profiles of symmetric cells assembled with different collectors at 5 mA cm⁻² and 5 mAh cm⁻². d Magnified view of selected cycle times between 5265 and 5300 h for the symmetric cell assembled with HPJH-AlSi. All the tests were measured at 25 °C using the 1 M NaPF₆ in diglyme =100 vol% electrolyte. e A comparative analysis of cumulative capacity and plating/stripping time in the recent demonstration of Na symmetric cells with our work. Detailed information for each demonstration are provided in Supplementary Table 2. f Radar plots of the five main electrochemical properties of different collectors. Source data are provided as a Source Data file.