Atomistic Modelling of Electrode Materials for Lithium and Post–lithium Ion Batteries

The first part of this report is about Fe- and Co-doped CeO $$_2$$ 2 as new insertion–type electrode for lithium and post–lithium ion batteries. Alternative anode materials with high volumetric and gravimetric capacity, moreover, allowing for fast charging are of utmost importance for next-generation lithium and post-lithium ion batteries. Keeping this in mind, we have investigated a new insertion-type electrode material, metal-doped CeO $$_2$$ 2 . While CeO $$_2$$ 2 shows limited capacity, the introduction of a small fraction of carefully selected dopants, results in a significant capacity increase. Interestingly, this capacity increase is accompanied by an off-centering of the dopant in the crystalline lattice and, moreover, results in the dopant atoms being reduced to their metallic state under alkaline metal insertion. In the second part of this report the H $$^{+}$$ + /Zn $$^{2+}$$ 2 + –intercalation in V $$_2$$ 2 O $$_5$$ 5 for aqueous Zn batteries is discussed. Vanadium oxides are a promising class of cathode materials for aqueous zinc metal batteries with a still debated intercalation mechanism. To corroborate the experimentally observed intercalation of both H $$^{+}$$ + and Zn $$^{2+}$$ 2 + into $$\delta $$ δ -Ca $$_{0.24}$$ 0.24 V $$_2$$ 2 O $$_5$$ 5 (CVO) and to furthermore identify a possible H $$^{+}$$ + /Zn $$^{2+}$$ 2 + -exchange intercalation, this phase was investigated by density functional theory (DFT). For this purpose, the concept of the computational hydrogen electrode (CHE) was exploited to determine the phase diagram in an electrochemical environment.