LiCoO2 is synthesized via a hydrothermal reaction of cobalt salt, LiOH·H2O and suitable amount of H2O2. A series of LiCoO2 + x% S mixtures are prepared by simply mixing LiCoO2 and S powder with different LiCoO2/S weight ratios, and investigated as anode material for alkaline secondary battery. At the discharge current density of 500mAg−1, LiCoO2 +5% S mixture electrode displays the maximum discharge capacity of 320mAhg−1. Meanwhile, the LiCoO2 +10% S mixture electrode shows the most outstanding cycle performance with a capacity retention rate of over 94% after 150th charge–discharge cycles. Moreover, the charge–discharge reaction mechanism of LiCoO2 + x% S mixture electrodes is also investigated.