DETERIORATION DETERMINING DEVICE OF RECHARGEABLE BATTERY, VEHICLE AND PROGRAM PROVIDED WITH IT AND METHOD FOR DETERIORATION DETERMINATION

摘要

PROBLEM TO BE SOLVED: To accurately determine the deterioration of a rechargeable battery due to irregular variation in load. SOLUTION: Charge and discharge current I of the rechargeable battery and voltage V between terminals are inputted (S104). When the inputted charge and discharge current I is approximately zero with the specified variation, a load history P as an indication showing the history of load on the rechargeable battery corresponding to the charge and discharge current I is calculated (S106 to S108). Voltage V when the load history P is a specified recharging history is set as polarization voltage Vc. At the same time, voltage V when the load history P is a specified discharging history is set as polarization voltage Vd (S110 to S 118). Then, when the voltage differenceΔV as a variation of polarization voltages Vc and Vd exceeds threshold Vref, the rechargeable battery is determined as deteriorated (S122). When a uniform standard is set as load history P, since the voltage differenceΔV when the load history P is at that standard directly reflects the degree of deterioration of the rechargeable battery, the deterioration can be determined more accurately. COPYRIGHT: (C)2004,JPO