Battery charging device, method for charging battery pack and battery pack

• US 6,008,620 A
• Filed: 11/12/1998
• Issued: 12/28/1999
• Est. Priority Date: 04/05/1996
• Status: Expired due to Term

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Nagano, Naoki, Koyama, Toshio
• Primary Examiner(s): Tso, Edward H.
• Application Number:
  US09/189,923
• Time in Patent Office: 411 Days
• Field of Search: 320/106, 320/132, 320/128, 320/148, 320/151, 320/152, 320/161, 320/162, 320/163, 320/164, 320/130, 320/DIG. 21, 320/FOR 138, 320/FOR 142, 320/FOR 147
• US Class Current: 320/106
• CPC Class Codes: H02J 7/00036 Charger exchanging data with battery
• CPC Class Codes: H02J 7/00047 with provisions for charging different types of batteries
• CPC Class Codes: H02J 7/0071 with a programmable schedule

Abstract

There is disclosed a battery charging device for charging a battery pack having a battery cell, the battery pack being capable of storing an information for a maximum charging current and a maximum charging voltage of the battery cell and communicating the information with the battery charging device, which includes a communication means for receiving the information indicative of the maximum charging current and the information indicative of the maximum charging voltage of the battery cell which is transmitted from the battery pack, and a control means for controlling charging current and voltage upon charging so as not to exceed the maximum charging current and the maximum charging voltage of the battery cell. Further, in accordance with the present invention, there are disclosed a method for charging the battery pack, and the battery pack capable of being mounted to various electronic apparatuses.

Claims

1. A battery pack having a communication terminal to output battery information, the battery pack comprising:

a battery cell capable of being charged or discharged;

memory means for storing maximum charging voltage information comprised of 16 bits;

a communication terminal for connection to a battery charger; and

processing means for transmitting said maximum charging voltage information stored in said memory means to said battery charger and for counting up/down a charged value in response to a charge/discharge of the battery cell and for transmitting said charged value to said battery charger.

2. The battery pack according to claim 1, wherein 1 bit of said maximum charging voltage information represents 0.01 V.

3. The battery pack according to claim 1, wherein said processing means increments/decrements said charged value in response to said charge/discharge of the battery cell in an operation period of said battery pack.

4. The battery pack according to claim 3, wherein said processing means calculates said increment/decrement of said charged value in accordance with a quantization step size of the charged value and an operation period of said battery pack.

5. The battery pack according to claim 4, wherein said processing means calculates said increment/decrement by calculating a product of said quantization step size and a value indicative of the present charge of the battery cell over said operation period.

6. The battery pack according to claim 3, wherein said processing means calculates said increment/decrement by calculating the product of 2ⁿ, where n is an integer, and the present charge of the battery cell.

7. The battery pack according to claim 6, wherein said processing means calculates the product of 2ⁿ and the present charge by bit shifting a binary representation of the present charge.

8. The battery pack according to claim 1, wherein said memory means stores additional information relating to said battery pack.

9. The battery pack according to claim 8, wherein said additional information includes a number of series connections of the battery pack coupled to a load.

10. The battery pack according to claim 8, wherein said additional information includes a number of parallel connections of the battery pack coupled to a load.

11. The battery pack according to claim 1, wherein said battery pack is one of a plurality of types of battery packs, each type of battery pack having a respective maximum charging voltage;

wherein said processing means retrieves from said memory means the maximum charging voltage information for a particular type of battery pack.

12. A battery pack having a communication terminal to output battery information, the battery pack comprising:

memory means for storing maximum charging voltage information comprised of 16 bits and maximum charging current information comprised of 8 bits;

a communication terminal for connection to a battery charger; and

processing means for transmitting said maximum charging voltage information and said maximum charging current information stored in said memory means to said battery charger and for counting up/down a charged value in response to a charge/discharge of the battery cell and for transmitting said charged value to said battery charger.

13. The battery pack according to claim 12, wherein said maximum charging voltage information more precisely represents a maximum capacity of said battery cell than said maximum charging current information.

14. The battery pack according to claim 12 wherein 1 bit of said maximum charging current information represents 0.1 A.