Abstract:
A simple and effective method was developed for preparing spherical zinc oxide/graphene (S-ZnO/rGO) composite material. In the synthesis process, GO prepared with the modified Humm3' method was dissolved in deionized water and mixed with S-ZnO powder. Then, the homogeneous solution was transferred to 100 mL PTFE lined stainless-steel autoclave and put into an oven at 180 ℃ for 12 h. The product was obtained with freeze-drying for 48 h. Subsequently, it was incorporated into the negative active materials at different dosages (0.5%, 1.0%, 1.5% and 2.0%) to prepare lead-acid batteries. The electrochemical properties of the batteries were studied. According to the results, the cycle life of the battery under the high-rate partial-state-of-charge (HRPSoC) condition showed the trend of first increasing and then decreasing with the doping amount of the S-ZnO/rGO composites increasing. The battery with 1.0% S-ZnO/rGO composite exhibited the best performance of HRPSoC cycle life, reaching 19 158 cycles, and it was improved by more than 165% compared with that of the ordinary lead-acid battery (7 210 cycles).