Hierarchical 3D micro-/nano-V2O5 (vanadium pentoxide) spheres as cathode materials for high-energy and high-power lithium ion-batteries

We facilely fabricate hierarchical 3D microspheres consisting of 2D V2O5 (vanadium pentoxide) nanosheets by a low temperature hydrothermal method and use it to structure hierarchical 3D micro-/nano-LIBs (lithium ion batteries) cathode. This is a template-free and facile method easy for scale-up production of hierarchical 3D micro-/nano-structured V2O5 spheres beneficial for high performance LIBs applications. Such a facile method resulted hierarchical 3D micro-/nano-V2O5 possess many unique features good for LIBs: (1) 2D V2O5 nanosheets facilitate the Li+ diffusions and electron transports; (2) hierarchical 3D micro-/nano-cathode structure built up by V2O5 nanosheet spheres will lead to the close and sufficient contact between electrolytes and activate materials and at the same time will create buffer volume to accommodate the volume change during discharging/charging process; and (3) micro-scale V2O5 spheres are easy to result in high cell packing density beneficial for high power battery. As revealed by the experimental results, the micro-/nano-V2O5 electrode demonstrates high initial discharge and charge capacities with no irreversible loss, high rate capacities at different currents and long-lasting lifespan. The high-energy and high-power performances of the micro-/nano-V2O5 electrode is ascribed to the unique hierarchical micro-/nano-structure merits of V2O5 spheres as abovementioned. In view of the advantages of facile fabrication method and unique features of 3D micro-/nano-V2O5 spheres for high power and high energy LIB battery, it is of great significance to beneficially broaden the applications of high-energy and high-power LIBs with creating novel hierarchical micro-/nano-structured V2O5 cathode materials.