Patent ID: 8378638
Filing Date: 2013-02-19
Classification: G01R

Abstract:
1. A battery status detecting method for detecting a battery status of a secondary battery, the method comprising: an open circuit voltage measuring step of measuring an open circuit voltage of the secondary battery by a voltage detecting unit using an output value of a temperature-dependent circuit unit; a charge rate calculating step of calculating a charge rate of the secondary battery based on charge rate characteristics indicating a relationship between the open circuit voltage and the charge rate of the secondary battery; an open circuit voltage correcting step of obtaining a temperature-corrected value of the open circuit voltage of the secondary battery according to a temperature of the secondary battery, based on first temperature characteristics indicating a relationship between the open circuit voltage and the temperature of the secondary battery; a charge rate correcting step of obtaining a temperature-corrected value of the charge rate of the secondary battery according to the temperature-corrected value of the open circuit voltage obtained in the open circuit voltage correcting step, based on the charge rate characteristics indicating the relationship between the open circuit voltage and the charge rate of the secondary battery; and a measured voltage correcting step of obtaining a temperature-corrected value of the measured open circuit voltage by correcting the measured open circuit voltage according to the temperature of the secondary battery based on second temperature characteristics of the temperature-dependent circuit unit indicating a relationship between input/output temperature characteristics of the temperature-dependent circuit unit and the temperature of the secondary battery, wherein the second temperature characteristics of the temperature-dependent circuit unit are represented by an approximated curve of a quadratic function formula of an output value of the temperature-dependent circuit unit, the quadratic function formula including the temperature as a variable and the output value of the temperature-dependent circuit unit as a quadratic function of the variable, and computing the temperature-corrected value of the measured open circuit voltage, at the measured voltage correcting step, based the temperature of the secondary battery and predetermined values of coefficients included in the quadratic function formula.