Relationship between discharge current and electrode action depth

 When the current is discharged at high current, the action depth of the active substance along the thickness direction is limited, and the larger the current is, the smaller the action depth is, the lower the degree of utilization of the active substance, the smaller the capacity given by the battery. When the electrode is discharged at low current density, the action depth of the active substance is deeper and denser, and the internal surface of the porous electrode can be fully utilized. However, when the electrode is discharged at high current density, the depth of action of the active substance decreases sharply, and the active material is rarely used in the depths of the active material. At this time, diffusion has become the determinant of limiting capacity. At high current discharge, due to the large storage of polarization and internal resistance, the terminal voltage of the battery is low and the loss of voltage drop increases, which makes the terminal voltage of the battery drop quickly and also affects the capacity.