Secondary battery management system, secondary battery management method and secondary battery management program for said secondary battery management system, and secondary battery system
A secondary battery management system, a secondary battery management method and a secondary battery management program for the secondary battery management system, and a secondary battery system with which a target state of charge of a secondary battery can be appropriately set by taking into consideration a degradation degree. A secondary battery management system includes a setting unit configured to set a temporary target state of charge of a secondary battery based on a target power amount, an estimating unit configured to estimate a degradation degree of the secondary battery based on an amount of change in a state of charge of the secondary battery over a predetermined constant-current charging period of the secondary battery, and a calculating unit configured to calculate a target state of charge of the secondary battery by correcting the temporary target state of charge in accordance with the degradation degree.
1. A secondary battery management system comprising:
a setting unit configured to set a temporary target state of charge of a secondary battery based on a target power amount;
an estimating unit configured to estimate a degradation degree of the secondary battery based on an amount of change in a state of charge of the secondary battery over a predetermined constant-current charging period of the secondary battery that is a predetermined period of time during which constant-current charging of the secondary battery is performed; and
a calculating unit configured to calculate a target state of charge of the secondary battery to be charged by correcting the temporary target state of charge in accordance with the degradation degree,
wherein after elapse of the constant-current charging period, the secondary battery is charged until the target state of charge calculated by the calculating unit is achieved.
2. The secondary battery management system according to claim 1 , wherein the estimating unit estimates the degradation degree of the secondary battery based on a ratio between a state of charge change rate that is an amount of change in a state of charge of the secondary battery in a present state over the constant-current charging period and an initial state of charge change rate of a change in the secondary battery in an initial state over the constant-current charging period.
3. The secondary battery management system according to claim 2 , wherein the constant-current charging period is set based on a sampling period related to measurement of the state of charge of the secondary battery, such that a measurement error is smaller than an upper limit value set in advance.
4. The secondary battery management system according to claim 2 , wherein the calculating unit issues a warning notification when the target state of charge is outside a state of charge allowable range set in advance.
5. The secondary battery management system according to claim 2 , further comprising a charging control unit configured to start constant-current charging of the secondary battery when the state of charge of the secondary battery reaches a reference state of charge.
6. A secondary battery system comprising:
a secondary battery;
a charging/discharging device configured to control a charging/discharging amount of current flowing through the secondary battery; and
the secondary battery management system described in claim 2 .
7. The secondary battery management system according to claim 1 , wherein the constant-current charging period is set based on a sampling period related to measurement of the state of charge of the secondary battery, such that a measurement error is smaller than an upper limit value set in advance.
8. The secondary battery management system according to claim 7 , wherein the calculating unit issues a warning notification when the target state of charge is outside a state of charge allowable range set in advance.
9. The secondary battery management system according to claim 7 , further comprising a charging control unit configured to start constant-current charging of the secondary battery when the state of charge of the secondary battery reaches a reference state of charge.
10. A secondary battery system comprising:
a secondary battery;
a charging/discharging device configured to control a charging/discharging amount of current flowing through the secondary battery; and
the secondary battery management system described in claim 7 .
11. The secondary battery management system according to claim 1 , wherein the calculating unit issues a warning notification when the target state of charge is outside a state of charge allowable range set in advance.
12. The secondary battery management system according to claim 11 , further comprising a charging control unit configured to start constant-current charging of the secondary battery when the state of charge of the secondary battery reaches a reference state of charge.
13. A secondary battery system comprising:
a secondary battery;
a charging/discharging device configured to control a charging/discharging amount of current flowing through the secondary battery; and
the secondary battery management system described in claim 11 .
14. The secondary battery management system according to claim 1 , further comprising a charging control unit configured to start constant-current charging of the secondary battery when the state of charge of the secondary battery reaches a reference state of charge.
15. A secondary battery system comprising:
a secondary battery;
a charging/discharging device configured to control a charging/discharging amount of current flowing through the secondary battery; and
the secondary battery management system described in claim 14 .
16. A secondary battery system comprising:
a secondary battery;
a charging/discharging device configured to control a charging/discharging amount of current flowing through the secondary battery; and
the secondary battery management system described in claim 1 .
17. A secondary battery management method comprising:
setting a temporary target state of charge of a secondary battery based on a target power amount;
estimating a degradation degree of the secondary battery based on an amount of change in a state of charge of the secondary battery over a predetermined constant-current charging period of the secondary battery that is a predetermined period of time during which constant-current charging of the secondary battery is performed; and
calculating a target state of charge of the secondary battery to be charged by correcting the temporary target state of charge in accordance with the degradation degree,
wherein after elapse of the constant-current charging period, the secondary battery is charged until the target state of charge calculated by the calculating unit is achieved.
18. A non-transitory tangible computer-readable storage medium storing a secondary battery management program for causing a computer to execute:
setting processing of setting a temporary target state of charge of a secondary battery based on a target power amount;
estimation processing of estimating a degree of the secondary battery based on an amount of change in a state of charge of the secondary battery over a predetermined constant-current charging period of the secondary battery that is a predetermined period of time during which constant-current charging of the secondary battery is performed; and
calculation processing of calculating a target state of charge of the secondary battery to be charged by correcting the temporary target state of charge in accordance with degradation of the degradation degree
wherein after elapse of the constant-current charging period, the secondary battery is charged until the target state of charge calculated by the calculating unit is achieved.