Lithium insertion behaviour of amorphous Li1-xV3O8 was compared with that of poorly crystalline and highly crystalline LiV3O8. This oxide retained the amorphous state during discharge and charge cycle and exhibited electrochemical performance inferior to the crystalline one, i.e., smaller discharge capacity and lower cycle efficiency. The crystallinity of the crystalline Li1+xV3O8 was one of the primary factors determining the rate of lithium insertion reaction.