Sun, Y.; Adelhelm, P.: Lifting the redox potential of layered sulfide cathodes for sodium-ion batteries. Matter 5 (2022), p. 2500-2501
10.1016/j.matt.2022.06.037
Abstract:
Lifting the redox potential of the cathode material is an important target to increase the energy density of sodium-ion batteries. Wang et al. report that this can be achieved for layered sulfides by careful combination of two different transition metals. The mixed compound NaTi1-yVyS2 shows a higher redox potential compared to the pure materials NaTiS2 and NaVS2. The synergistic effect is believed to be due to an unusually strong covalency in the Ti–V–S system. Among various improvements, this approach leads to a 15% increase in energy density.