Properties of single and double layer V₂O₅ polymorphs from first principles

V₂O₅ is a very promising battery electrode material that can intercalate not only Li, but also more abundant alkaline metals such as Na and K, and even multivalent ions such as Mg, Ca, Zn, and Al. V₂O₅ can occur in several polymorphs. Several of these are layered in nature, with both single layer and double layer structural motives occuring. During intercalation phase transitions can take place, and such phase transitions can be detrimental to battery performance. Understanding these transitions requires knowledge of the energetics and structural properties of the various V₂O₅ polymorphs.

We provide such understanding by employing density functional theory (DFT) calculations based on hybrid functionals, with an explicit inclusion of van der Waals interactions. Based on our results we discuss the structural and electronic properties of 8 different single and double layered V₂O₅ polymorphs, and show the role polarons play in electronic transport. The obtained insights can be used to optimize future V₂O₅-based battery electrodes.