Benefits of electronic wiring and spacers on lithium storage in nanostructured lithium-ion battery anodes

Abstract

Photoresponse of individual V₂O₅ nanowire (NW) under different controlled conditions were investigated. Individual V₂O₅ NW showed a significant photoresponse at vacuum condition and very small photocurrent (∼1 nA) in ambient condition, upon global irradiation of 808 nm laser beam. The photoconducting properties of the V₂O₅ NW are investigated at various pressure conditions and with varying laser power. The observed sub-bandgap energy laser irradiation induced photoresponse can be attributed to factors such as defect level excitation, desorption of adsorbed gas species and laser induced heating effects. The demand for high power density lithium-ion batteries (LIBs) for diverse applications ranging from mobile electronics to electric vehicles have resulted in an upsurge in the development of nanostructured electrode materials worldwide. Graphite has been the anode of choice in commercial LiBs. Due to several detrimental electrochemical and environmental issues, efforts are now on to develop alternative non-carbonaceous anodes which are safe, nontoxic and cost effective and at the same time exhibit high lithium storage capacity and rate capability. Titania (TiO₂) and tin (Sn) based systems have gained much attention as alternative anode materials. Nanostructuring of TiO₂ and SnO₂ have resulted in enhancement of structural stability and electrochemical performances. Additionally, electronic wiring of mesoporous materials using carbon also effectively enhanced electronic con- ductivity of mesoporous electrode materials. We discuss in this article the beneficial influence of structural spacers and electronic wiring in anatase titania (TiO₂) and tin dioxide (SnO₂).