The solubility and deposition of LiCoO2 in carbonate melts have been studied under the cathode condition (1-7 atm, CO2-air or CO2-O-2-N-2 working atmosphere). The solubility of LiCoO2 in the (Li0.62K0.38)(2)CO3 melt for the applied pressure of 1 atm was found to be directly proportional to P-Co2(1.5) and P-O2(-0.25), while in the case when applied pressure was 7 atm it was proportional to P-CO2(1.7) and P-O2(-0.3). Although the dependence of P-CO2 and P-O2, on the solubility at 7 atm was a little different from the result at 1 atm, it was thought that the dissolution of LiCoO2 at the elevated pressure would be regarded as the acidic dissolution mechanism. The solubility of LiCoO2 in the (Li0.52Na0.48)(2)CO3 melt was less than half of that in the (Li0.62K0.38)(2)CO3 melt and this trend was the same as that of NiO. Moreover the deposition rate ofLiCoO(2) in the (Li0.62K0.38)(2)CO3 melt was smaller than that of NiO and was about one-thirtieth.