The aluminum vanadates, AlxV6O13+y, were found to reversibly intercalate lithium. These vanadates were found to deliver reversible specific capacities in the range of 100-300 mAh/g, with average voltages of 2.3-2.5 V, where 0.1 < x < 1.0. The efficiency of reversible insertion depended on the stoichiometric ratio of Al:V in the vanadate structure. Stable rechargeable performance was obtained by the incorporation of small amounts of aluminum in the cobalt vanadates (Co(VO3)(2)). Specific capacities in the range of zoo-rao mAh/g with average voltages of 2.4 V for AlxCo3V6O13+y (where 0 < x < 2 and 3 < y < 8) were achieved.