BATTERY STATE ESTIMATION DEVICE AND METHOD

To provide a battery state estimation device and method with which it is possible to diagnose a cause of increase in a battery's resistance to see whether the cause of increase in a battery's resistance is a problem associated with contact or due to the degradation of the battery.SOLUTION: There is provided a battery state estimation device for estimating a state of a battery. The battery state estimation device comprises: a resistance estimation unit which, assuming the battery as being composed of an open-circuit voltage power supply, a series resistor, and one or more parallel circuits including a resistor and a capacitor, estimates the values of the open-circuit voltage, series resistor and parallel circuits; a parameter table unit for preserving the values of series resistor and parallel circuits obtained in an initial state of the battery; and a resistor diagnosis unit for comparing the resistance values of the series resistor and parallel circuits regarding the battery as having been obtained by the resistance estimation unit with the resistance values of the series resistor and parallel circuits preserved in the parameter table unit, and diagnosing the cause of increase in resistance to see whether the cause is a problem associated with contact of the battery or due to the degradation of the battery itself.SELECTED DRAWING: Figure 1 【課題】電池の抵抗の増加原因を、接触性の問題なのか、電池の劣化によるものかを診断することができる電池状態推定装置および方法を提供する。【解決手段】電池の状態を推定する電池状態推定装置であって、電池を、開放電圧の電源と、直列抵抗と、抵抗とコンデンサを含む１つ以上の並列回路で構成されたものとして、開放電圧と直列抵抗と並列回路の抵抗の値を推定する抵抗推定部と、電池の初期状態において求めた直列抵抗と並列回路の抵抗の値を保存するパラメータテーブル部と、抵抗推定部で求めた電池についての直列抵抗と並列回路の抵抗の値と、パラメータテーブル部に保存している直列抵抗と並列回路の抵抗の値を比較し、抵抗増加の原因が電池の接触性か、電池自体の劣化によるものかを抵抗診断部を備えることを特徴とする電池状態推定装置。【選択図】図１