We, for the first time, demonstrate that orthorhombic V₂O₅ can exhibit superior electrochemical performance in sodium ion batteries when uniformly coated inside nanoporous carbon. The encapsulated V₂O₅ shows a specific capacity as high as 276 mAh/g, while the whole nanocomposite exhibits a capacity of 170 mAh/g. The V₂O₅/C composite was...