Battery apparatus, charging control apparatus, and charging control method
A control is performed to set a current value exceeding a nominal capacity of the secondary battery to first charging current to charge the secondary battery, compare the measured voltage of the secondary battery with first threshold voltage that is lower than a prescribed charging voltage while performing constant current charging with the set first charging current, decrease the first charging current to be second charging current when the measured voltage is higher than the first threshold voltage, and increase the first threshold voltage by a predetermined amount to be second threshold voltage, compare the measured voltage of the secondary battery with the second threshold voltage that is lower than the prescribed charging voltage while performing constant current charging with the set second charging current, decrease the second charging current to be third charging current when the measured voltage is higher than the second threshold voltage, and increase the second threshold voltage by a predetermined amount to be third threshold voltage, repeat a comparison of the measured voltage with the threshold voltage and a change of the charging current and a change of the threshold voltage, and complete rapid charging in a case where n th charging current is decreased to a predetermined value and the measured voltage is higher than the predetermined value.
1. A battery apparatus, comprising:
a secondary battery;
a measurement circuit that measures a voltage and a current of the secondary battery; and
a controller, to which the measured voltage and the measured current are supplied from the measurement circuit, that controls a charging voltage and a charging current of the secondary battery, the controller configured to:
set a current value, exceeding a nominal value, as a first charging current to charge the secondary battery;
compare the measured voltage of the secondary battery with a first threshold voltage lower than a prescribed charging voltage, while performing first constant current charging with the set first charging current;
decrease the first charging current to obtain a second charging current when the measured voltage is higher than the first threshold voltage, and increase the first threshold voltage by a first predetermined amount to obtain a second threshold voltage;
compare the measured voltage of the secondary battery with the second threshold voltage lower than the prescribed charging voltage while performing second constant current charging with the second charging current;
decrease the second charging current to obtain a third charging current when the measured voltage is higher than the second threshold voltage, and increase the second threshold voltage by a second predetermined amount to obtain a third threshold voltage;
complete rapid charging in a case where the third charging current is decreased to a first predetermined value and the measured voltage is higher than a second predetermined value;
determine a degradation degree of the secondary battery after the completion of the rapid charging;
set a first value of the charging voltage for constant voltage charging based on the determined degradation degree; and
switch the rapid charging to the constant voltage charging based on the set first charging voltage for the constant voltage charging,
wherein the first predetermined value is a value of the charging current when the rapid charging is switched to the constant voltage charging, and
wherein the first value of the charging voltage at the constant voltage charging after the completion of the rapid charging and the second predetermined value are varied based on a number of cycles of the secondary battery.
2. The battery apparatus according to claim 1 , wherein
the second predetermined value is a second value of the charging voltage when the rapid charging is switched to the constant voltage charging.
3. The battery apparatus according to claim 1 , wherein
the controller is further configured to set a second charging voltage higher than the prescribed charging voltage of the secondary battery for the rapid charging.
4. The battery apparatus according to claim 1 , wherein
the controller is further configured to perform one of third constant current charging or the constant voltage charging after the rapid charging is completed.
5. The battery apparatus according to claim 1 , wherein
a charging parameter is varied based on the degradation degree of the secondary battery.
6. A charging control apparatus, to which a measured voltage and a measured current are supplied from a secondary battery to be charged, that controls a charging voltage and a charging current of the secondary battery, comprising:
a controller configured to
set a current value, exceeding a nominal value, as a first charging current to charge the secondary battery;
compare the measured voltage of the secondary battery with a first threshold voltage lower than a prescribed charging voltage, while performing first constant current charging with the set first charging current;
decrease the first charging current to obtain a second charging current when the measured voltage is higher than the first threshold voltage, and increase the first threshold voltage by a first predetermined amount to obtain a second threshold voltage;
compare the measured voltage of the secondary battery with the second threshold voltage lower than the prescribed charging voltage while performing second constant current charging with the second charging current;
decrease the second charging current to obtain a third charging current when the measured voltage is higher than the second threshold voltage, and increase the second threshold voltage by a second predetermined amount to obtain a third threshold voltage;
complete rapid charging in a case where the third charging current is decreased to a first predetermined value and the measured voltage is higher than a second predetermined value;
determine a degradation degree of the secondary battery after the completion of the rapid charging;
set a first value of the charging voltage for constant voltage charging based on the determined degradation degree; and
switch the rapid charging to the constant voltage charging based on the set first charging voltage for the constant voltage charging,
wherein the first predetermined value is a value of the charging current when the rapid charging is switched to the constant voltage charging, and
wherein the first value of the charging voltage at the constant voltage charging after the completion of the rapid charging and the second predetermined value are varied based on a number of cycles of the secondary battery.
7. The charging control apparatus according to claim 6 , wherein
the controller is further configured to set a second charging voltage higher than the prescribed charging voltage of the secondary battery for the rapid charging.
8. The charging control apparatus according to claim 6 , wherein
the controller is further configured to perform one of third constant current charging or the constant voltage charging after the rapid charging is completed.
9. The charging control apparatus according to claim 6 , wherein
a charging parameter is varied based on the degradation degree of the secondary battery.
10. A charging control method that receives a measured voltage and a measured current of a secondary battery to be charged and controls a charging voltage and a charging current of the secondary battery, comprising
setting a current value, exceeding a nominal value, as a first charging current to charge the secondary battery;
comparing the measured voltage of the secondary battery with a first threshold voltage lower than a prescribed charging voltage, while performing first constant current charging with the set first charging current;
decreasing the first charging current to obtain a second charging current when the measured voltage is higher than the first threshold voltage, and increase the first threshold voltage by a first predetermined amount to obtain a second threshold voltage;
comparing the measured voltage of the secondary battery with the second threshold voltage lower than the prescribed charging voltage while performing second constant current charging with the second charging current;
decreasing the second charging current to obtain a third charging current when the measured voltage is higher than the second threshold voltage, and increase the second threshold voltage by a second predetermined amount to obtain a third threshold voltage;
completing rapid charging in a case where the third charging current is decreased to a first predetermined value and the measured voltage is higher than a second predetermined value;
determining a degradation degree of the secondary battery after the completion of the rapid charging;
setting a first value of the charging voltage for constant voltage charging based on the determined degradation degree; and
switching the rapid charging to the constant voltage charging based on the set charging voltage for the constant voltage charging,
wherein the first predetermined value is a value of the charging current when the rapid charging is switched to the constant voltage charging, and
wherein the first value of the charging voltage at the constant voltage charging after the completion of the rapid charging and the second predetermined value are varied based on a number of cycles of the secondary battery.