Hierarchical vanadium pentoxide microflowers with excellent long-term cyclability at high rates for lithium ion batteries

• V2O5 microflowers composed of thin nanosheets are prepared by a two-step process.
• V2O5 microflowers exhibit a capacity of 126 mAh g−1 at 200 mA g−1 over 150 cycles.
• The capacity could retain at 104 mAh g−1 after 1500 cycles at 1 A g−1.
• The performance can be associated with their structure and capacitive contribution.

Hierarchical V2O5 microflowers composed of thin nanosheets have been achieved by a solvothermal reaction first and then a low-temperature calcination. These micro-flowers are characterized by powder X-ray diffractometer (XRD), scanning electron microscope (SEM), and transmission electron microscope (TEM). The nanoscale size and sheet-like structure of the building blocks in V2O5 microflowers make them a promising cathode material for lithium ion batteries. After 1500 cycles at a current density of 1 A g−1, the reversible capacity of V2O5 microflowers is kept at 104 mAh g−1. Even at a rate of 2 A g−1, the reversible capacity is still above 80 mAh g−1 after 3000 cycles. The excellent electrochemical properties of V2O5 microflowers are associated with their unique structure and capacitive feature.

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