| 摘要 |
PROBLEM TO BE SOLVED: To provide a method and device for estimating the open-circuit voltage of a vehicle battery capable of relatively accurately estimating the open-circuit voltage of the battery in a relatively short time after the end of charge or discharge without requiring temperature compensation. SOLUTION: An open-circuit voltage measuring means 23a-1 measures the open-circuit voltage of the battery within a certain period of time after a predetermined period of time has elapsed since the end of the charge or discharge of the battery. An approximate expression determining means 23a-2 determines a predefined power approximate expression having a negative power, from the values of differences between a plurality of open-circuit voltages and assumed open-circuit voltages. A computation control means 23a-3 causes the approximate expression determining means to repeatedly make determination of the power approximate expression while renewing the assumed open-circuit voltage until the power of the power approximate expression becomes -0.5 or approximately -0.5. The assumed open-circuit voltage when either of these requirements is met is estimated to be the open-circuit voltage.
|
