| abstract |
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 Mg 2+ 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 Mg 2+ into a metastable one-dimensional polymorph of V 2 O 5 . Not only does ζ-ν 2 O 5 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. |