Abstract: Biochar is emerging as a promising electrode material for energy storage devices. To develop high-performance electrochemical materials derived from biochar and achieve high-value utilization of biomass, exploring the energy storage capacities of various biochar materials has garnered extensive attention. In this study, the structural properties of spirulina char and poplar char were characterized, and the sodium storage capacities of these biochar materials were analyzed. Differences in the structural properties of the two types of biochar were found, and the sodium storage capacity of poplar char was greater than that of spirulina char.