초록 ▼

The present invention discloses a battery charging controller for balancing the charged batteries. The battery charging controller comprises a battery reference voltage generator, a voltage balancing module and a balance judging circuit. The battery charging controller determines which one has the l

The present invention discloses a battery charging controller for balancing the charged batteries. The battery charging controller comprises a battery reference voltage generator, a voltage balancing module and a balance judging circuit. The battery charging controller determines which one has the lower voltage between battery units of a battery module according to reference voltages generated by the battery reference voltage generator. The voltage balancing module controlled by the balance judging circuit allows the charging current of the lower-voltage battery larger than the charging current of the higher-voltage battery in such that the final voltages of the battery units are substantially equaled when they are completely saturated.

대표청구항 ▼

1. A battery balanced charging controller, for balancing a battery charge of a first battery and a second battery, with a negative terminal of the first battery being electrically coupled to a positive terminal of the second battery to form a connecting point, and a positive terminal of the first ba

1. A battery balanced charging controller, for balancing a battery charge of a first battery and a second battery, with a negative terminal of the first battery being electrically coupled to a positive terminal of the second battery to form a connecting point, and a positive terminal of the first battery serving as a first terminal, and a negative terminal of the second battery serving as a second terminal, the battery balanced charging controller comprising: a battery reference voltage generator coupled between the first terminal and the second terminal, for providing a first series of battery balance judgment signals and a second series of battery balance judgment signals, the first series of battery balance judgment signals comprising a high-plus reference signal and a low-plus reference signal, and the second series of battery balance judgment signals comprising a low-minus reference signal and a high-minus reference signal, wherein a voltage level of the high-plus reference signal is higher than that of the low-minus reference signal;a voltage balance module comprising a first balance current unit and a second balance current unit, the first balance current unit coupled to the first terminal and the connecting point, and the second balance current unit coupled to the second terminal and the connecting point; anda balance judgment circuit coupled to the connecting point, the battery reference voltage generator and the voltage balance module, and determining whether to enter a first condition or a second condition according to the first series of battery balance judgment signals, the second series of battery balance judgment signals and a voltage level of the connecting point;wherein the voltage balance module provides a balance current to one of the first battery and the second battery whichever is lower in voltage level when the balance judgment circuit is under the first condition. 2. The battery balanced charging controller according to claim 1, wherein the battery reference voltage generator further generates a balance reference signals as the low-plus reference signal and the high-minus reference signal, and a voltage level of the balance reference signal is substantially equal to an average of the voltage levels of the first battery and the second battery. 3. The battery balanced charging controller according to claim 1, wherein the balance judgment circuit enters the first condition when the voltage level of the connecting point is higher than that of the high-plus reference signal or lower than that of the low-minus reference signal, and enters the second condition when the voltage level of the connecting point is between the high-plus reference signal and the low-minus reference signal. 4. The battery balanced charging controller according to claim 3, wherein the battery reference voltage generator further generates a balance reference signal with a voltage level thereof being substantially equal to an average of the voltage levels of the first battery and the second battery, and the balance judgment circuit controls the voltage balance module to provide the balance current until the voltage level of the first battery is equal to that of the second battery when being under the first condition. 5. The battery balanced charging controller according to claim 1, wherein the first balance current unit comprises a first switch coupled to the first terminal and the connecting point, and the second balance current unit comprises a second switch coupled to the second terminal and the connecting point. 6. The battery balanced charging controller according to claim 5, wherein the balance judgment circuit comprises a first comparator and a second comparator, the first comparator compares the low-minus reference signal with the voltage level of the connecting point to output a first comparison signal, the second comparator compares the high-plus reference signal with the voltage level of the connecting point to output a second comparison signal, the balance judgment circuit generates a first control signal and a second control signal according to the first comparison signal and the second comparison signal to respectively control the first switch and the second switch, and thus the balance current flows through the first switch when the voltage level of the connecting point is lower than a voltage level of the low-minus reference signal and flows through the second switch when the voltage level of the connecting point is higher than a voltage level of the high-plus reference signal. 7. The battery balanced charging controller according to claim 6, wherein a resistor is coupled to the connecting point and the voltage balance module. 8. The battery balanced charging controller according to claim 6, further comprising a time delay unit coupled to the balance judgment circuit and the voltage balance module, such that one of the first switch and the second switch is conducted after a predetermined time period calculating from the other being cutoff. 9. The battery balanced charging controller according to claim 1, wherein the battery reference voltage generator comprises a first resistor, a second resistor, and a third resistor, the first resistor is coupled to the first terminal, the third resistor is coupled to the second terminal, and the second resistor is coupled to the first resistor to generate the high-plus reference signal and coupled to the third resistor to generate the low-minus reference signal, wherein a resistance value of the first resistor is equal to a resistance value of the third resistor and a resistance value of the second resistor is smaller than the resistance value of the first resistor. 10. The battery balanced charging controller according to claim 1, wherein the balance judgment circuit enters the first condition when the voltage level of the connecting point is higher than that of the high-plus reference signal or lower than that of the low-minus reference signal, and enters the second condition when the voltage level of the connecting point is between that of the high-minus reference signal and that of the low-plus reference signal. 11. A battery charging controller for charging a battery module with a plurality of battery units, the battery charging controller coupled to a positive terminal and a negative terminal of each battery units, the battery charging controller comprising: a battery charging controlling unit for determining an amount of a charging current and generating an enable signal according to a battery current detecting signal and a battery voltage detecting signal indicative of a current and a voltage of the battery module, respectively; anda battery balanced charging controlling unit coupled to the battery charging controlling unit and a positive terminal and a negative terminal of each of the battery units of the battery module, the battery balanced charging controlling unit comparing the voltages of N battery units connected in series for determining which battery unit among the N battery units connected in series having the lowest voltage and which battery unit among the N battery units having the highest voltage, and determining whether to modulate the amount of the charging current flowing through any N battery units connected in series in the battery module according to the voltages of the N battery units connected in series when receiving the enable signal, to cause that the charging current flowing through the battery unit with the lowest voltage among the N battery units connected in series is larger than that flowing through the battery unit with the highest voltage among the N battery units connected in series, wherein N is an integer greater than zero. 12. The battery charging controller according to claim 11, wherein the battery balanced charging controlling unit starts to modulate the amount of the charging current when a voltage difference between the battery unit with the lowest voltage and the battery unit with the highest voltage of the N battery units connected in series is more than a predetermined percentage. 13. The battery charging controller according to claim 12, wherein the battery balanced charging controlling unit stops modulating the amount of the charging current when the voltage difference between the battery unit with the lowest voltage and the battery unit with the highest voltage of the N battery units connected in series is zero. 14. The battery charging controller according to claim 11, wherein the battery charging controlling unit has a first charging mode and a second charging mode and an average of the charging currents in the first charging mode is larger than that in the second charging mode. 15. The battery charging controller according to claim 14, wherein the battery charging controlling unit generates the enable signal only in the first charging mode or only in the second charging mode. 16. The battery charging controller according to claim 14, wherein the first charging mode is a constant current charging mode and the second charging mode is a constant voltage charging mode, or the first charging mode is a constant voltage charging mode and the second charging mode is a constant current charging mode. 17. The battery charging controller according to claim 12, wherein the battery balanced charging controlling unit comprises at least two battery balanced charging controllers for controlling the charging current flowing through the corresponding N battery units connected in series. 18. The battery charging controller according to claim 17, wherein at least one battery unit corresponds to two batteries balanced charging controllers. 19. A battery balanced charging controller, for modulating charging currents flowing through a plurality of battery units connected in series of a battery module, comprising: a battery reference voltage generator coupled to positive terminals and negative terminals of the plurality of the battery units for providing plural series of battery balance judgment signals, each series of the battery balance judgment signals comprising a high-plus reference signal, a low-plus reference signal, a low-minus reference signal, and a high-plus reference signal, with a voltage level of the high-plus reference signal being largest among voltage levels of the high-minus reference signal, the low-plus reference signal, and the low-minus reference signal and the voltage level of the low-minus reference signal being smallest;a voltage balance module coupled to connecting points of every two of the battery units connected in series, a positive terminal and a negative terminal of the battery module; anda balance judgment circuit coupled to the connecting points, the battery reference voltage generator and the voltage balance module, the balance judgment circuit determining whether to modulate the charging current of each of the battery units according to voltage levels of the connecting points and voltage levels of the plural series of the battery balance judgment signals;wherein the balance judgment circuit modulates the charging currents of any two of the battery units when the voltage level of the connecting point is higher than that of the corresponding high-plus reference signal or lower than that of the corresponding low-minus reference signal, and stops modulating the charging currents of any two of the battery units when the voltage level of the connecting point is between that of the corresponding high-minus reference signal and that of the corresponding low-plus reference signal. 20. The battery balanced charging controller according to claim 19, further comprising a plurality of resistors coupled to corresponding connecting points and the voltage balance module.