Sodium ion batteries could finally be ready for prime time

High energy density sodium ion batteries using Cobalt oxide plating are providing better performance than lithium ion batteries.

Sodium ion batteries (SIBs) have emerged as the most direct route to developing more cost effective and more sustainably produced metal-ion batteries due to their similarity in chemistry to Lithium ion batteries LIBs and the 1000× greater natural abundance of sodium in comparison to lithium.

A carbon nucleation layer to enable highly efficient and stable sodium plating and stripping as the basis for a new approach for sodium batteries: the anode-free sodium battery. The exceptional energy density of ∼400 Wh/kg and versatility of this approach that builds upon naturally abundant low-cost materials and aqueous processing is the first demonstration that sodium batteries have the promise of outperforming LIB technology and filling the desperately needed demand for a cost-effect, high-performance battery for grid-scale storage.

Electrochemical studies show this configuration to provide highly stable and efficient plating and stripping of sodium metal over a range of currents up to 5 mA/cm2, sodium loading up to 14 mAh/cm2, and with long-term endurance exceeding 1000 cycles at a current of 0.7 mA/cm2. Building upon this anode-free architecture, we demonstrate a full cell using a presodiated pyrite cathode to achieve energy densities of 400 Wh/kg, far surpassing recent reports on SIBs and even the theoretical maximum for LIB technology while still relying on naturally abundant raw materials and cost-effective aqueous processing.