Solubility and deposition of LiCoO2 in a molten carbonate

The solubility and deposition of LiCoO2 in carbonate melts have been studied under the cathode condition (1–7 atm, CO2–air or CO2–O2–N2 working atmosphere). The solubility of LiCoO2 in the (Li0.62K0.38)2CO3 melt for the applied pressure of 1 atm was found to be directly proportional to P1.5CO2 and P−0.25O2, while in the case when applied pressure was 7 atm it was proportional to P1.7CO2 and P−0.3O2. Although the dependence of PCO2 and PO2 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)2CO3 melt was less than half of that in the (Li0.62K0.38)2CO3 melt and this trend was the same as that of NiO. Moreover the deposition rate of LiCoO2 in the (Li0.62K0.38)2CO3 melt was smaller than that of NiO and was about one-thirtieth.