An Anode-Free Sodium All-Solid-State Battery

Anode-free batteries possess the optimal cell architecture due to their reduced weight, volume, and cost. However, their implementation has been limited by unstable anode morphological changes and anode-liquid electrolyte interface reactions. An electrochemically stable solid electrolyte can solve these issues by enabling the deposition of dense sodium metal. Furthermore, a novel type of aluminum current collector can achieve intimate solid-solid contact with the solid electrolyte which allows highly reversible sodium plating and stripping at both high areal capacities and current densities, previously unobtainable with conventional aluminum foil. A sodium anode-free all-solid-state battery full-cell is demonstrated with stable cycling for several hundred cycles. This cell architecture serves as a future direction for other battery chemistries to enable low-cost, high-energy-density, and fast charging batteries.