ELECTROCHEMICAL STORAGE INCORPORATING SIZE- AND MORPHOLOGY-CONTROLLED METASTABLE VANADIUM PENTOXIDE AS A CATHODE MATERIAL FOR ION BATTERIES

摘要

The Li-ion paradigm of battery technology is fundamentally constrained by the monovalency of the Li-ion. A straightforward solution is to transition to multivalent ion chemistries, with Mg²⁺ the most obvious candidate due to considerations of size and mass. Despite early interest, the realization of Mg batteries has faced myriad obstacles, including a sparse selection of cathode materials demonstrating the ability to reversibly insert divalent ions. Disclosed herein is evidence of reversible topochemical and electrochemical insertion of Mg²⁺ into a metastable one-dimensional polymorph of V₂O₅. Not only does ζ-ν₂O₅ represent a rare addition to the pantheon of functional Mg battery cathode materials, but is also distinctive in exhibiting a combination of high stability, high specific capacity due to ion insertion, and moderately high operating voltage.