In Situ Mechanical Measurements in Vanadium Pentoxide Cathodes for Aqueous Zinc-Ion Batteries during Battery Cycling

Abstract

Aqueous rechargeable zinc-ion batteries (AZIBs) are currently gaining traction as a potential successor to lithium-ion batteries for use in large-scale, stationary energy storage applications due to their inherent safety, low environmental impact, and low-cost. Recent advances have made breakthroughs in these anode and electrolyte stability; however, cathode development still lags preventing the commercial use of AZIBs. Vanadium pentoxide (V2O5) shows promise as a cathode material due to its low cost, environmental friendliness, and high specific capacity versus zinc (in excess of 400 mAh/g)1. V2O5 exhibits a single layer crystal structure which provides a large number of theoretical storage sites2. However, charge storage mechanisms and driving force behind the capacity fade in V2O5 are not well known yet. The lack of understanding surrounding insertion and storage mechanisms of zinc ions into V2O5 cathodes must be addressed to progress toward commercial viability.In this study, we aim to conduct in-operando stress and stress measurements in V2O5 during battery cycling. Curvature interferometry and digital image correlation techniques will be employed for in operando stress and strain measurements, respectively the composite V2O5 cathode will consist of a 7:2:1 ratio of active material, super P, and PVDF binder. By combining stress and strain measurements, coupled with spectroscopy studies, our goal is to identify the how interfacial stress and structural strains play a role on the charge storage mechanisms in V2O5.