Novel Li VO Nanostructures Grown in Highly Efficient Microwave Irradiation Strategy and Their In-Situ Lithium Storage Mechanism.

The investigation of novel growth mechanisms for electrodes and the understanding of their in situ energy storage mechanisms remains major challenges in rechargeable lithium-ion batteries. Herein, a novel mechanism for the growth of high-purity diversified Li VO nanostructures (including hollow nanospheres, uniform nanoflowers, dispersed hollow nanocubes, and ultrafine nanowires) has been developed via a microwave irradiation strategy. In situ synchrotron X-ray diffraction and in situ transmission electron microscope observations are applied to gain deep insight into the intermediate Li VO and Li VO phases during the lithiation/delithiation mechanism. The first-principle calculations show that lithium ions migrate into the nanosphere wall rapidly along the (100) plane. Furthermore, the Li VO hollow nanospheres deliver an outstanding reversible capacity (299.6 mAh g after 100 cycles) and excellent cycling stability (a capacity retention of 99.0% after 500 cycles) at 200 mA g . The unique nanostructure offers a high specific surface area and short diffusion path, leading to fast thermal/kinetic reaction behavior, and preventing undesirable volume expansion during long-term cycling.