Lead-acid battery manufacturers belong to the high power energy consumption industry, and they have great energy-saving potential by improving formation process. Considering the peak-valley electricity pricing mechanism, and aiming at minimizing the total power cost of battery packs during a formation cycle, a mathematic optimal dispatching model of lead-acid battery formation is established based on the lead-acid battery formation process, with the premise that there is no feedback to superior power grid and no additional large-scale energy storage devices installed. The conversion efficiency of charging-discharging device is considered together with the constraints of load power of charging-discharging devices, no feedback to power grid, switching time interval of battery packs, switching frequency during a formation dispatch cycle. Based on the actual operation data of a lead-acid battery factory, the particle swarm optimization algorithm is used to solve the optimal model. Results show that the total power consumption cost can be reduced by 5% after optimization. The research in this paper can provide reference for lead-acid battery industry in energy-saving reconstruction and efficiency promotion.