Amorphous LiNiVO4 thin-film anode for microbatteries grown by pulsed laser deposition

Thin films of lithium nickel vanadates are deposited by pulsed-laser deposition from targets with different lithium contents. The as-deposited films are mainly amorphous and possess smooth and dense surfaces as revealed by X-ray diffraction and scanning-electron microscopy. The initial loss in capacity between the first discharge and charge decreases with increase in the lithium content in the films. The film grown from the target of Li1.2NiVO4 gives the best performance with a retainable capacity as high as 410 μAh per cm2 μm. There is almost no loss in capacity from the 11th up to the 50th cycle even though a fast decay occurs during the first several cycles. Cyclic voltammograms reveal cathodic peaks at 1.78 and 0.56 V and anodic peaks at 1.27 and 2.47 V, in line with the shapes of the discharge and charge curves.