Battery state detection device, secondary battery system, program product, and battery state detection method

1. A battery state detector that detects a battery state, comprising:

a voltage detector;

a first permissible current calculator that is configured to calculate a first maximum permissible current of a battery based on a voltage of the battery detected by the voltage detector;

a second permissible current calculator that is configured to calculate a second maximum permissible current of the battery without using the voltage of the battery, wherein the calculation is based on at least stored internal resistance characteristics and temperature measurements received from a temperature detector; and

a corrector that is configured to compare the first maximum permissible current and the second maximum permissible current and to perform a predetermined correction process on the basis of the comparison result, wherein

the corrector also being configured to perform the correction process by correcting the calculation result of the second maximum permissible current by the second permissible current calculator or characteristic information of the battery which is used for the second permissible current calculator to calculate the second maximum permissible current, the corrector also being configured to store a plurality of correction coefficients based on a difference between the first permissible maximum current and the second permissible maximum current in advance, and to perform the correction process using the correction coefficient selected from the plurality of correction coefficients, and the corrector also being configured to determine the correction coefficient which is used for the correction process on the basis of a charging/discharging time of the battery and a polarization voltage of the battery.

2. The battery state detector according to claim 1 , further comprising a state-of-health (SOH) estimator that is configured to monitor at least one of the calculation result of the first permissible maximum current by the first permissible current calculator, the calculation result of the second permissible maximum current by the second permissible current calculator, and the result of the correction process performed by the corrector, the state-of-health (SOH) estimator also being configured to estimate a state of health of the battery based on the monitoring.

3. The battery state detector according to claim 2 , wherein the SOH estimator is configured to determine whether a lifespan of the battery expires on the basis of the estimation result of the state of health of the battery.

4. The battery state detector according to claim 1 , wherein the first permissible maximum current includes a first permissible charging current for charging of the battery, and a first permissible discharging current corresponding to discharging of the battery, the second permissible maximum current includes a second permissible charging current for charging of the battery and a second permissible discharging current corresponding to discharging of the battery, the corrector compares the first permissible maximum charging current and the second permissible maximum charging current and performs the correction process on the basis of the comparison result when the battery is charged, and the corrector compares the first permissible maximum discharging current and the second permissible maximum discharging current and performs the correction process on the basis of the comparison result when the battery is subjected to discharging.

5. A secondary battery comprising:

the battery state detector according to claim 4 ; and

a secondary battery of which a voltage is detected by the voltage detector and which is subjected to charging or discharging based on a permissible current determined on the basis of at least one of the first maximum permissible current and the second maximum permissible current.

6. A non-transitory, computer readable storage medium storing instructions, which when executed cause a processor to:

calculate, using a first permissible current calculator, a first maximum permissible current of a battery based on a voltage of the battery detected by a voltage detector;

calculate, using a second permissible current calculator, a second maximum permissible current of the battery without using the voltage of the battery, wherein the calculation is based on at least stored internal resistance characteristics and temperature measurements received from a temperature detector; and

compare, using a corrector, the first maximum permissible current and the second maximum permissible current and to perform a predetermined correction process on the basis of the comparison result, the corrector also being configured to perform the correction process by correcting the calculation result of the second maximum permissible current by the second permissible current calculator or characteristic information of the battery which is used for the second permissible current calculator to calculate the second maximum permissible current, the corrector also being configured to store a plurality of correction coefficients based on a difference between the first permissible maximum current and the second permissible maximum current in advance, and to perform the correction process using the correction coefficient selected from the plurality of correction coefficients, and the corrector also being configured to determine the correction coefficient which is used for the correction process on the basis of a charging/discharging time of the battery and a polarization voltage of the battery.

7. A method for detecting a battery state, the method comprising:

calculating, using a first permissible current calculator, a first maximum permissible current of a battery based on a voltage of the battery detected by a voltage detector;

calculating, using a second permissible current calculator, a second maximum permissible current of the battery without using the voltage of the battery, wherein the calculation is based on at least stored internal resistance characteristics and temperature measurements received from a temperature detector; and

comparing, using a corrector, the first maximum permissible current and the second maximum permissible current and to perform a predetermined correction process on the basis of the comparison result, the corrector also being configured to perform the correction process by correcting the calculation result of the second maximum permissible current by the second permissible current calculator or characteristic information of the battery which is used for the second permissible current calculator to calculate the second maximum permissible current, the corrector also being configured to store a plurality of correction coefficients based on a difference between the first permissible maximum current and the second permissible maximum current in advance, and to perform the correction process using the correction coefficient selected from the plurality of correction coefficients, and the corrector also being configured to determine the correction coefficient which is used for the correction process on the basis of a charging/discharging time of the battery and a polarization voltage of the battery.