HYBRID BATTERY PACK AND METHODS OF CHARGING AND DISCHARGING THE SAME

• US 20080048608A1
• Filed: 08/01/2007
• Published: 02/28/2008
• Est. Priority Date: 08/22/2006
• Status: Active Grant

• Current Assignee: Samsung SDI Company Limited
• Original Assignee: Samsung SDI Company Limited
• Inventors: LIM, Seong Ben, Choi, Hong Seok
• Granted Patent: US 7,728,547 B2
• Time in Patent Office: Days
• US Class Current: 320/106
• CPC Class Codes: H01M 10/441 for several batteries or cells simultaneously or sequentially
• CPC Class Codes: H01M 16/00 Structural combinations of different types of electrochemical generators
• CPC Class Codes: H02J 7/0018 using separate charge circuits
• CPC Class Codes: H02J 7/0025 Sequential battery discharge in systems with a plurality of batteries
• CPC Class Codes: H02J 7/00302 Overcharge protection
• CPC Class Codes: H02J 7/00304 Overcurrent protection
• CPC Class Codes: H02J 7/00306 Overdischarge protection
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

A hybrid battery pack and methods of charging and discharging the same make it possible to manage at least two power sources by one circuit. The hybrid battery pack includes a first power source having a first switching circuit, a second power source connected to the first power source in parallel and having a second switching circuit, a current sensor serially connected to the first and second power sources to sense the currents of the first and second power sources, and a controller to obtain the voltages of the first and second power sources so that the first and second power sources are not over-charged or over-discharged and to calculate the entire capacity of the first and second power sources using the amount of currents obtained by the current sensor.

Claims

1. A hybrid battery pack, comprising:

a first power source having a first switching circuit;

a second power source connected to the first power source in parallel and having a second switching circuit;

a current sensor serially connected to the first and second power sources to sense the currents of the first and second power sources; and

a controller to obtain the voltages of the first and second power sources so that the first and second power sources are not over-charged or over-discharged and to calculate the entire capacity of the first and second power sources using the amount of currents obtained by the current sensor.

2. The hybrid battery pack as claimed in claim 1, wherein the first power source and/or the second power source is at least one of a fuel cell, a solar cell, a cylinder type lithium ion battery, a polygon type lithium ion battery, a pouch type lithium polymer battery, and a pouch type lithium ion battery.

3. The hybrid battery pack as claimed in claim 1, wherein the first power source and the second power source comprise battery cells having at least one of different shapes, chemical characteristics, capacities, or charging voltages.

4. The hybrid battery pack as claimed in claim 1, wherein the controller outputs a charging stop signal to the respective switching circuit when the voltage of the first power source or the second power source is an over-charging voltage so that the respective switching circuit stops the first power source or the second power source from being charged.

5. The hybrid battery pack as claimed in claim 1, wherein the controller outputs a discharging stop signal to the respective switching circuit when the voltage of the first power source or the second power source is an over-discharging voltage so that the respective switching circuit stops the first power source or the second power source from being discharged.

6. The hybrid battery pack as claimed in claim 1, wherein the controller obtains the temperatures of the first power source or the second power source to output the charging stop signal or the discharging stop signal to the respective switching circuit when the sensed temperatures are other than allowed temperatures so that the respective switching circuit stops the first power source or the second power source from being charged or discharged.

7. The hybrid battery pack as claimed in claim 1, wherein the first switching circuit of the first power source senses a current from the current sensor to stop the first power source from being charged or discharged during occurrence of an over-current.

8. The hybrid battery pack as claimed in claim 1 wherein the second switching circuit of the second power source senses a current from the current sensor to stop the second power source from being charged or discharged during occurrence of an over-current.

9. The hybrid battery pack as claimed in claim 1, further comprising a fuse provided in a charging and discharging path and the first power source further comprises an auxiliary switching circuit so that the fuse is cut off during the over-charging.

10. The hybrid battery pack as claimed in claim 1, further comprising a fuse provided on a charging and discharging path and the second power source further comprises an auxiliary switching circuit so that the fuse is cut off during the over-charging.

11. The hybrid battery pack as claimed in claim 1, wherein the controller sums the capacity information of the first power source and the capacity information of the second power source to transmit the summation to an external system using a communication line.

12. The hybrid battery pack as claimed in claim 1, wherein, in the first power source, a charging switch and a discharging switch are serially connected to a charging and discharging path and the switches are turned on and off by the first switching circuit.

13. The hybrid battery pack as claimed in claim 1, wherein, in the second power source, a charging switch and a discharging switch are serially connected to a charging and discharging path and the switches are turned on and off by the second switching circuit.

17. The hybrid battery pack as claimed in claim 1, wherein the controller coulomb counts the respective currents of the first power source and the second power source to calculate the respective charging capacities of the first and second power sources.

14. A method of controlling a hybrid battery pack comprising at least two power sources and a controller to control power supplied from a charging circuit to charge the hybrid battery pack without interruption, the method comprising:

intercepting the charging paths of all power sources;

stopping generation of a charging current;

requesting controller information on one of the power sources to be charged;

selecting the power source to be charged and connecting the selected power source to the charging circuit to secure a charging path;

transmitting information on the selected power source to be charged and a charging preparation completion signal to the charging circuit; and

generating a charging current.

15. A method of controlling a hybrid battery pack comprising at least two power sources and a controller to control power supplied to a load to discharge the hybrid battery pack without interruption, the method comprising:

intercepting a charging path of one of the power sources to be stopped from being discharged with respect to the load;

intercepting a charging path of the other power source to be newly discharged with respect to the load;

connecting the other power source to be newly discharged to the load to secure a discharging path; and

intercepting the discharging path of the power source to be stopped from being discharged from the load.

16. The method as claimed in claim 15, wherein the controller simultaneously connects the discharging paths of the two power sources to the load for a predetermined time when the discharging paths are changed from the one power source to the other power source with respect to the load.

18. A battery pack, comprising:

a first rechargeable cell to supply power;

a second rechargeable cell to supply power, and which is of a different type from the first rechargeable cell;

a first switching unit to control supply of power to and/or from the first rechargeable cell;

a second switching unit to control supply of power to and/or from the second rechargeable cell, and which is parallel to the first switching unit; and

a controller to control the first and second switching units to supply power from the first and second rechargeable cells without interruption.

19. The battery pack as claimed in claim 18, wherein the controller controls to begin supply of power from the second rechargeable cell prior to ending supply of power from the first rechargeable cell.

20. The battery pack as claimed in claim 18, wherein the first and the second rechargeable cells have at least one of different shapes, chemical characteristics, capacities, and charging voltages.

21. The battery pack as claimed in claim 18, wherein the first and the second rechargeable cells are at least one of a fuel cell, a solar cell, a cylinder type lithium ion battery cell, a polygon type lithium ion battery cell, a pouch type lithium polymer battery cell, and a pouch type lithium ion battery cell.

22. The battery pack as claimed in claim 18, wherein the controller transmits information on the shapes, the chemical characteristics, the capacities, and the charging voltages of the first and second rechargeable cells to be charged during charging operations to a charging circuit so that the charging circuit supplies a suitable charging current based on the information of the first and second rechargeable cells to be charged.

23. The battery pack as claimed in claim 18, wherein when one of the first and second rechargeable cells is to be stopped from being discharged and the other of the first and second rechargeable cells is to be discharged, the controller controls discharging paths of the first and second rechargeable cells to be connected to each other for a predetermined time to minimize or prevent the supply of power to an external system from being stopped or interrupted.