摘要 |
[Problem] To further improve estimation accuracy in a cell-state-estimating device for estimating a state of charge (SOC) of a secondary cell. [Solution] When the SOC is estimated based on integration of the charge/discharge current, the effect of sensor error cannot be disregarded, and the effect of such error accumulates over time. In contrast, estimating the SOC based on measured values of cell voltage and cell temperature depends greatly on estimation accuracy with respect to load-generation patterns. Thus, according to the present invention, when both SOC estimation techniques are combined, one of the estimation techniques is reset on the basis of reliability corresponding to the operating conditions, or an input current value taken as a prerequisite in calculating the SOC estimate in a cell model is set on the basis of the reliability, thereby enabling an SOC estimation value to be calculated with maximum accuracy in accordance with the operating conditions. |