Apparatus and method for charging battery by lowering charge power in phase
View Patent ↗Disclosed is an apparatus (and method) for charging a battery having a voltage measuring unit for measuring a voltage, a control unit for outputting a charge control signal corresponding to an early charging mode in which the battery is charged until a voltage of the battery rises to a preset cut-off voltage (Vc) and a charge control signal corresponding to a late charging mode in which the battery is charged while lowering a charge power in phases, and a charging unit for providing a charge power corresponding to the charge control signal to the battery, wherein a point of lowering the charge power in phases is associated with a point at which the voltage of the battery reaches the cut-off voltage again by the lowered charge power. Therefore, a voltage level reached at full charge of a battery may be raised in a simple and efficient way.
1. An apparatus for charging a battery, comprising:
a voltage measuring unit for measuring a voltage of a battery;
a control unit for outputting a charge control signal corresponding to an early charging mode in which the battery is charged until a voltage of the battery rises to a preset cut-off voltage (Vc) and a charge control signal corresponding to a late charging mode in which the battery is charged while lowering a charge power in phases; and
a charging unit for providing a charge power corresponding to the charge control signal to the battery,
wherein a point of lowering the charge power in phases is associated with a point at which the voltage of the battery reaches the cut-off voltage again by the lowered charge power,
wherein, in the late charging mode, the control unit outputs the charge control signal for lowering both a charge voltage and a charge current or the control unit outputs the charge control signal for lowering the charge current,
wherein, when outputting the charge control signal for lowering both the charge voltage and the charge current in the late charging mode, the control unit outputs the charge control signal so that the charge voltage approaches the cut-off voltage, and
wherein, when outputting the charge control signal for lowering the charge current in the late charging mode, the control unit outputs the charge control signal so that the charge voltage rises according to a preset voltage range.
2. The apparatus for charging a battery according to claim 1 , wherein the cut-off voltage (Vc) is set higher than an open circuit voltage when the battery is fully charged.
3. The apparatus for charging a battery according to claim 1 , wherein the cut-off voltage (Vc) is set so that an open circuit voltage when the battery finishes charging is 95% or above an open circuit voltage when the battery is fully charged.
4. The apparatus for charging a battery according to claim 1 , wherein in the late charging mode, a phased decrement (ΔP) of the charge power is ⅕ or below a charge power (CP 0 ) applied when the early charging mode terminates.
5. The apparatus for charging a battery according to claim 1 , wherein in the late charging mode, a phased decrement (ΔP) of the charge power is constant.
6. The apparatus for charging a battery according to claim 1 , wherein in the late charging mode, a phased decrement (ΔP) of the charge power proportionally increases or decreases.
7. The apparatus for charging a battery according to claim 1 , wherein the late charging mode terminates when a charge power level at the present point, which has been lowered in phases, reaches a preset critical value.
8. The apparatus for charging a battery according to claim 7 , wherein the critical value is 0 W.
9. The apparatus for charging a battery according to claim 1 , wherein in the late charging mode, a phased decrement (ΔP) of the charge power is constant, and
wherein the late charging mode terminates when a charge power level at the present point, which has been lowered in phases, reaches a preset critical value.
10. The apparatus for charging a battery according to claim 9 , wherein the critical value is 0 W.
11. The apparatus for charging a battery according to claim 1 , wherein in the early charging mode, the battery is charged by means of a constant-power manner, a constant-current manner, a constant-voltage manner, or their mixtures.
12. The apparatus for charging a battery according to claim 1 , wherein, in the late charging mode, the control unit outputs the charge control signal for lowering both the voltage and the charge current.
13. The apparatus for charging a battery according to claim 1 , wherein, in the late charging mode, the control unit outputs the charge control signal for lowering the charge current.
14. The apparatus for charging a battery according to claim 1 , further comprising a memory unit that stores the cut-off voltage, the phased decrement of the charge power, and a charge power condition when the late charging mode terminates.
15. A battery driving system, comprising:
a battery;
a load for receiving power from the battery; and
an apparatus for charging a battery, defined in claim 1 .
16. The battery driving system according to claim 15 , wherein the load is an electric-driven unit or a portable device.
17. A battery pack, comprising:
a battery; and
an apparatus for charging a battery, defined in claim 1 .
18. A method for charging a battery, comprising:
an early charging stage in which a battery is charged until a voltage of the battery rises to a preset cut-off voltage (Vc); and
a late charging stage in which the battery is charged while lowering a charge power in phases,
wherein a point of lowering the charge power in phases is associated with a point at which the voltage of the battery reaches the cut-off voltage again by the lowered charge power,
wherein the late charging stage lowers the charge power in phases by lowering both a charge voltage and a charge current or by lowering the charge voltage,
wherein, when outputting a charge control signal for lowering both the charge voltage and the charge current, the late charging stage lowers the charge power in phases so that the charge voltage approaches the cut-off voltage, and
wherein, when outputting the charge control signal for lowering the charge current, the late charging stage lowers the charge power in phases so that the charge voltage rises according to a preset voltage range.
19. The method for charging a battery according to claim 18 , wherein the cut-off voltage (Vc) is set higher than an open circuit voltage when the battery is fully charged.
20. The method for charging a battery according to claim 18 , wherein the cut-off voltage (Vc) is set so that an open circuit voltage when the battery finishes charging is 95% or above an open circuit voltage when the battery is fully charged.
21. The method for charging a battery according to claim 18 , wherein in the late charging stage, a phased decrement (ΔP) of the charge power is ⅕ or below a charge power (CP 0 ) applied when the early charging stage terminates.
22. The method for charging a battery according to claim 18 , wherein in the late charging stage, a phased decrement (ΔP) of the charge power is constant.
23. The method for charging a battery according to claim 18 , wherein in the late charging stage, a phased decrement (ΔP) of the charge power proportionally increases or decreases.
24. The method for charging a battery according to claim 18 , wherein the late charging stage terminates when a charge power level at the present point, which has been lowered in phases, reaches a preset critical value.
25. The method for charging a battery according to claim 24 , wherein the critical value is 0 W.
26. The method for charging a battery according to claim 18 , wherein in the late charging stage, a phased decrement (ΔP) of the charge power is constant, and
wherein the late charging stage terminates when a charge power level at the present point, which has been lowered in phases, reaches a preset critical value.
27. The method for charging a battery according to claim 26 , wherein the critical value is 0 W.
28. The method for charging a battery according to claim 18 , wherein in the early charging stage, the battery is charged by means of a constant-power manner, a constant-current manner, a constant-voltage manner, or their mixtures.
29. The method for charging a battery according to claim 18 , wherein, in the late charging state, outputting the control signal for lowering both the charge voltage and the charge current, the late charging stage lowers the charge power in phases so that the charge voltage approaches the cut-off voltage.
30. The method for charging a battery according to claim 18 , wherein, in the late charging state, outputting the control signal for lowering the charge current, the late charging stage lowers the charge power in phases so that the charge voltage rises according to a preset voltage range.
31. The method for charging a battery according to claim 18 , further comprising:
storing the cut-off voltage, the phased decrement of the charge power, and a charge power condition when the late charging stage terminates.