Electrochemical properties of LiNiO2 cathode after TiO2 or ZnO addition

LiNiO2 was prepared by solid state reaction, and LiNiO2 was mixed with 1-, 2-, or 5 wt% TiO2 or ZnO for the preparation of cathodes for a lithium ion battery. The electrochemical properties of the cathodes were investigated and the effects of the addition of TiO2 or ZnO were discussed. The voltage vs. capacity curves for charge and discharge at different numbers of cycles for LiNiO2, 2 wt% TiO2-added LiNiO2, and 2 wt% ZnO2-added LiNiO2 showed that in all the samples the first discharge capacity is much smaller than the first charge capacity. The addition of TiO2 or ZnO decreased the discharge capacities, but improved the cycling performance. The discharge capacities of LiNiO2 and 2 wt% TiO2-added LiNiO2 decreased as the number of cycles increased. However, the discharge capacity of 2 wt% ZnO-added LiNiO2 increased overall as the number of cycles increased. The −dx/|dV| vs. voltage curves for the 1st and 2nd cycles of 0, 1-, 2-, or 5 wt% TiO2 or ZnO-added LiNiO2 showed that all the samples underwent four phase transitions during charging and discharging.