Phase change cold energy storage is widely used in commercial air conditioning systems. The cold energy charging rate decreases gradually in the storage containers, and foam freezing can significantly increase the charging rate. Microchannels inside the frozen body are the basis for the generation of foam but have not been given attention in previous studies. The research presented herein used an experimental approach to investigate the external factors that lead to the formation of microchannels and used quantitative parameters to describe the structure of the microchannels. It was found that a higher temperature (in - 40 ∼ − 20 °C) and a higher pore jet velocity (in 1.89–51 m/s) correspond to a higher germination capacity. Gas pore spacing, air flow rate, gas pore diameter, and initial water height were found to influence the magnitude of the gas mutual disturbances on the gas pores, which, as a result, affected the growth and branching capacity. The growth and branching capacity could not be optimized synergistically. The results of this study concluded that it is feasible to actively control the charge rate of phase change cold energy storage over a wide range of values via the manipulation of external factors.