Charging device for secondary battery and charging method for secondary battery
A charging device includes charging power detection unit and full charge determination unit. The charging device further includes charging control unit adapted to repeatedly execute a additional charging control until the number of times of the full charge determination reaches a predetermined full charge determination count. The charging device further includes unit adapted to detect the temperature of the secondary battery, and full charge determination count setting unit adapted to set a larger full charge determination count as the temperature decreases at least based on the temperature of the secondary battery when the full charge determination is made.
1. A charging device for secondary battery, comprising:
a charging power supply capable of outputting power for charging a secondary battery;
a charging power detection unit configured to detect power to be charged to the secondary battery by the charging power supply;
a temperature detection unit configured to detect a temperature of the secondary battery; and
a controller programmed to determine that the secondary battery is fully charged if chargeable power calculated based on a detection value of the charging power detection unit becomes equal to or less than predetermined power set in advance,
the controller being programmed to repeatedly execute a charging control, in which:
power is supplied to the secondary battery from the charging power supply until it is determined that the secondary battery is fully charged,
the supply of power to the secondary battery from the charging power supply is stopped when it is determined that the secondary battery is fully charged,
the supply of power is resumed upon the elapse of a predetermined time after the supply of power is stopped and the supply of power is continued until it is determined that the secondary battery is fully charged again, until the number of times the secondary battery is fully charged reaches a full charge determination count which is a predetermined count indicating the number of times additional charging is performed,
the controller being programmed to set the full charge determination count at least based on the temperature detected by the temperature detection unit when it is determined that the secondary battery is fully charged,
wherein the controller is programmed to set a larger full charge determination count as the temperature detected by the temperature detection unit decreases.
2. The charging device for secondary battery according to claim 1 , wherein:
the controller is further programmed to set a time for stopping the supply of power at least based on the temperature detected by the temperature detection unit when it is determined that the secondary battery is fully charged,
wherein the controller is further programmed to set a longer stop time for stopping the supply of power as the temperature detected by the temperature detection unit decreases.
3. The charging device for secondary battery according to claim 2 , wherein:
the controller is further programmed to reductively correct the set stop time every time it is determined that the secondary battery is fully charged.
4. The charging device for secondary battery according to claim 3 , wherein:
the controller is further programmed to hold the stop time when the full charge determination count reaches the predetermined count thereafter once the full charge determination count reaches the predetermined count.
5. A charging method for secondary battery, comprising:
a charging power detection step of detecting power to be charged to a secondary battery by a charging power supply capable of outputting power for charging the secondary battery;
a full charge determination step of determining that the secondary battery is fully charged if chargeable power calculated based on a detection value of the charging power detection step becomes equal to or less than predetermined power set in advance;
a charging control step of repeatedly executing a charging control, in which:
power is supplied to the secondary battery from the charging power supply until it is determined that the secondary battery is fully charged,
the supply of power to the secondary battery from the charging power supply is stopped when it is determined that the secondary battery is fully charged,
the supply of power is resumed upon the elapse of a predetermined time after the supply of power is stopped and the supply of power is continued until it is determined that the secondary battery is fully charged again, until the number of times the secondary battery is fully charged reaches a full charge determination count which is a predetermined count indicating the number of times additional charging is performed;
a temperature detection step of detecting a temperature of the secondary battery; and
a full charge determination count setting step of setting a larger predetermined count as the temperature detected by the temperature detection step decreases at least based on the temperature detected by the temperature detection step when it is determined that the secondary battery is fully charged.
6. A charging device for secondary battery, comprising:
a charging power supply capable of outputting power for charging a secondary battery;
charging power detection means for detecting power to be charged to the secondary battery by the charging power supply;
full charge determination means for determining that the secondary battery is fully charged if chargeable power calculated based on a detection value of the charging power detection means becomes equal to or less than predetermined power set in advance;
charging control means for repeatedly executing a charging control, in which:
power is supplied to the secondary battery from the charging power supply until it is determined that the secondary battery is fully charged,
the supply of power to the secondary battery from the charging power supply is stopped when it is determined that the secondary battery is fully charged,
the supply of power is resumed upon the elapse of a predetermined time after the supply of power is stopped and the supply of power is continued until it is determined that the secondary battery is fully charged again, until the number of times the secondary battery is fully charged reaches a full charge determination count which is a predetermined count indicating the number of times additional charging is performed;
temperature detection means for detecting a temperature of the secondary battery; and
full charge determination count setting means for setting the full charge determination count at least based on the temperature detected by the temperature detection means when it is determined that the secondary battery is fully charged,
wherein the full charge determination count setting means sets a larger full charge determination count as the temperature detected by the temperature detection means decreases.