Presodiation Architected Robust Surface Enables Packaging Optimal Performance of Sodium-Ion Batteries

Presodiation has shown great promise in compensating sodium storage losses. In the absence of a mechanistic understanding of how presodiation affects the surface of an electrode material, packaging optimization is restricted. Focusing on interfaces, we illustrate the working principle of presodiation in virtue of short-circuiting internal circuits. The presodiated carbon nanotubes (PS-CNTs) provide a thin, denser, and more robust solid electrolyte interfacial layer, enabling a high initial Coulombic efficiency (ICE), high power density, and cycling stability with the merits of uniformly distributed NaF. As a result, our assembled sodium-ion battery (SIB) full cell with PS-CNT has an ICE of 91.6% and an energy density of 226 Wh kg^–1, which was superior to the pristine CNT control electrode (ICE of 42.9% and energy density of 163 Wh kg^–1). The gained insights can be practically applied to directly promote the commercial uses of carbon-based materials in sodium-ion batteries.