Ultra-thin (<10nm diameter) VO2(B) nanowires have been synthesised, characterised structurally and morphologically and their lithium intercalation electrochemistry investigated. The wires exist in bundles and exhibit significant preferred orientation. They have a capacity to intercalate lithium of 265mAhg−1 (Li0.82VO2(B)) at a rate of 10mAg−1 compared with thicker wires of 50–100nm diameter which exhibit a capacity of 200mAhg−1 at the same rate. The load curves, structure and morphology remain stable on cycling.