A power stabilizing system comprising: a power supplying mechanism that supplies a DC power; an electric load that is connected to the power supplying mechanism; a power line that connects between the power supplying mechanism and the electric load; and a storage pack that is connected to the power line, wherein a charging/discharging curve of the storage pack, measured with a constant C-rate, has a step difference that passes through a rated voltage of the power supplying mechanism, and on a lower-state of charge, SOC, side than a start point of the step difference in the charging/discharging curve of the storage pack, an average discharging voltage is -20% or more of the rated voltage and/or a voltage of a peak top on a dQ/dV curve obtained by differentiating the discharging curve of the storage pack with respect to the voltage is -20% or more of the rated voltage, and on a higher-SOC side than an end point of the step difference in the charging/discharging curve of the storage pack, an average charging voltage is +20% or less of the rated voltage and/or a voltage of a peak top on a dQ/dV curve obtained by differentiating the charging curve of the storage pack with respect to the voltage is +20% or less of the rated voltage, and wherein the step difference of the charging/discharging curve refers to a range in which the absolute value of the ratio of the change of the voltage, ΔV, of at least one of the charging curve and the discharging curve relative to the change of SOC, ΔSOC, is equal to (0.008 × the rated voltage) V/% or more, when the SOC is in the range of 5% to 95%, and wherein the start point of the step difference is the minimum voltage of the discharging curve within a range of one step difference, and the corresponding value of the SOC at the minimum voltage, and the end point of the step difference is the maximum voltage of the charging curve within a range of the same one step difference, and the corresponding value of the SOC at the maximum voltage. a power supplying mechanism that supplies a DC power; an electric load that is connected to the power supplying mechanism; a power line that connects between the power supplying mechanism and the electric load; and a storage pack that is connected to the power line, wherein a charging/discharging curve of the storage pack, measured with a constant C-rate, has a step difference that passes through a rated voltage of the power supplying mechanism, and on a lower-state of charge, SOC, side than a start point of the step difference in the charging/discharging curve of the storage pack, an average discharging voltage is -20% or more of the rated voltage and/or a voltage of a peak top on a dQ/dV curve obtained by differentiating the discharging curve of the storage pack with respect to the voltage is -20% or more of the rated voltage, and on a higher-SOC side than an end point of the step difference in the charging/discharging curve of the storage pack, an average charging voltage is +20% or less of the rated voltage and/or a voltage of a peak top on a dQ/dV curve obtained by differentiating the charging curve of the storage pack with respect to the voltage is +20% or less of the rated voltage, and wherein the step difference of the charging/discharging curve refers to a range in which the absolute value of the ratio of the change of the voltage, ΔV, of at least one of the charging curve and the discharging curve relative to the change of SOC, ΔSOC, is equal to (0.008 × the rated voltage) V/% or more, when the SOC is in the range of 5% to 95%, and wherein the start point of the step difference is the minimum voltage of the discharging curve within a range of one step difference, and the corresponding value of the SOC at the minimum voltage, and the end point of the step difference is the maximum voltage of the charging curve within a range of the same one step difference, and the corresponding value of the SOC at the maximum voltage.