Unraveling the Lithium Storage Mechanism at low Potentials in Pure and Bismuth doped Niobium Oxide Anodes for Lithium-Ion Batteries

Understanding the lithium storage mechanism of alternative and novel anode materials for lithium-ion batteries (LIBs) is crucial in order to elevate LIB technology towards the next generation. We, therefore, aim to unravel the de-/lithiation mechanism of Nb2O5 anodes when used between 3.0 V and 0.01 V, i.e., exploiting the entire active potential range - which offers enhanced specific capacities, but has not been elucidated in detail so far. Interestingly, the specific capacity can be boosted even further via Bi doping, which has so far never been reported as well. Spectra in the XANES region from operando XAS measurements will provide information about the electronic structure and the changes in oxidation state of the electroactive species. The longer ex situ EXAFS measurements will provide complementary information on the local structural changes around the two absorbers, and the results are expected to contribute to the difficult task of realizing next-generation LIBs.