Performance of LiCoO₂-coated NiO cathode under pressurized conditions

The properties of LiCoO₂-coated NiO cathodes prepared by the solution impregnation technique were investigated. The electrode performance of the LiCoO₂-coated cathodes were comparable with that of the conventional NiO cathode at 1, 3, and 5atm and the prepared cathodes showed no performance decay at least for the first 1000 h at pressurized conditions. The post-analysis revealed that the LiCoO₂-coated cathodes were effective in suppressing NiO dissolution up to 51% at 1atm and 50% at 3atm. However, the suppression of the NiO dissolution was found to be much less effective (about 11% of suppression) at 5atm. The number of impregnations applied, in other words, the amount of LiCoO₂ incorporated into the NiO cathode seemed to have no significant effect on suppressing the NiO dissolution. The Ni contents in the matrix after the 1000 h operations did not vary with increasing the LiCoO₂ amount in the NiO cathodes from 0.25-0.8mol%. In the cell with the co-flow configuration, the highest Ni content in the matrix was found at the gas inlet side and the Ni content in the matrix decreased along the gas flow direction.