Uniform second Li ion intercalation in solid state ε-LiVOPO4

In this follow-on work as part of the NECCESS EFRC, a combination of hard and soft x–ray photoelectron and absorption spectroscopy techniques to depth profile solid state synthesized LiVOPO4, a promising multi-electron electrode for rechargeable lithium-ion batteries. This work confirms that limited kinetics in the high voltage regime are responsible for the inability to fully intercalate 2 Li in this material. The evolution from LiVOPO4 to Li2VOPO4 via the intermediate phases as predicted in our previous work (“Thermodynamics, Kinetics and Structural Evolution of ε-LiVOPO4 over Multiple Lithium Intercalation”) is confirmed by O K–edge absorption spectroscopy and DFT calculations. Yuh-chieh Lin and Shyue Ping Ong are co-authors in this work.