Rate capability tests at selected current densities. All half-cells were cycled between 0.01 and 2.0 V versus Na/Na+ using Na metal as the counter electrode, while the full cells were cycled between 1.3 and 3.8 V using a specific current density of 100 mA g−1 (with respect to the anode) in a 1mNaPF6 in PC + 5% FEC electrolyte.
