A combined process has been developed for recovering cobalt and regenerating cathode material from leach liquor of spent LiCoO2 batteries. Cobalt of 98% can be selectively separated from leach liquor using ammonium oxalate of 1.15 (mole ratio) at pH of 2.0, 55 °C, and 40 min. Kinetics analysis indicates that precipitation of cobalt is controlled by a combination of surface chemical reaction and diffusion. The Ea value of precipitation is 19.68 kJ/mol obtained from the second-order model of (1 − a)−1 = k′t + c. Based on the TG/DSC curves of oxidation of cobalt oxalate, it is found that formation of Co3O4 oxidized from cobalt oxalate is in according with the model of randomly nucleating followed by nucleus growth. The Ea value is 84.93 kJ/mol that is provided by the suitable model of g(α) = [−ln(1 − α)]1/3. Then, lithium is recovered from the filtrate as Li2CO3 with the purity of 99.5% by precipitation method. Finally, new cathode material with a good electrochemical performance is regenerated using obtained Co3O4 and lithium carbonate through solid phase method.