Power supply methods and arrangements

• US 8,004,244 B2
• Filed: 08/15/2007
• Issued: 08/23/2011
• Est. Priority Date: 08/15/2006
• Status: Active Grant

• Current Assignee: Lenovo PC International Limited (Lenovo Group Ltd.)
• Original Assignee: Lenovo Singapore Pte Limited (Lenovo Group Ltd.)
• Inventors: Matsumoto, Takeshi, Horikoshi, Seita, Corkell, Anthony F., Odaohhara, Shigefumi, Wong, Tin-Lup, Cromer, Daryl
• Primary Examiner(s): Tso; Edward
• Assistant Examiner(s): Berhanu; Samuel
• Application Number:
  US11/839,091
• Publication Number:
  US 20080042618A1
• Time in Patent Office: 1,469 Days
• Field of Search: 320/134, 320/135, 320/136
• US Class Current: 320/134
• CPC Class Codes: H01M 10/4207 for several batteries or cells simultaneously or sequentially
• CPC Class Codes: H01M 10/44 Methods for charging or discharging circuits for charging H02J7/00
• CPC Class Codes: H01M 10/441 for several batteries or cells simultaneously or sequentially
• CPC Class Codes: H01M 10/448 End of discharge regulating measures
• CPC Class Codes: H01M 10/48 Accumulators combined with arrangements for measuring, testing or indicating the condition of cells, e.g. the level or density of the electrolyte constructional details of current conducting connections for detecting conditions inside cells or batteries, e.g. details of voltage sensing terminals, H01M50/569
• CPC Class Codes: H01M 10/482 for several batteries or cells simultaneously or sequentially
• CPC Class Codes: H01M 50/209 adapted for prismatic or rectangular cells H01M50/216 takes precedence
• CPC Class Codes: H01M 50/24 adapted for protecting batteries from their environment, e.g. from corrosion thermal insulation H01M10/658
• CPC Class Codes: H01M 50/30 Arrangements for facilitating escape of gases
• 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: H02J 7/00309 Overheat or overtemperature protection
• CPC Class Codes: H02J 7/0031 using battery or load disconnect circuits H02J9/002 takes precedence
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

In the context of a notebook computer, multiple battery safety measures in the computer, battery pack, and individual battery cells. These battery packs include industry standard safety mechanisms as well as additional safeguards designed to increase safety. The additional safeguards can be categorized in the following ways. The first safeguard deals with multiple, independent levels of battery monitoring. The second safeguard employs abnormal condition detection methods. The third safeguard deals with improvements to mechanical and thermal design.

Claims

1. An apparatus comprising:

a battery for powering a computer system; and

a control module which controls said battery and monitors a plurality of battery conditions;

said control module-further acting to;

use a first fuse to prompt disabling battery power to the computer system responsive to a first voltage associated with a battery over-charge condition; and

use a second fuse to redundantly prompt disabling battery power to the computer system responsive to a second voltage associated with the battery over-charge condition;

wherein said control module monitors and responds to the first voltage and the second voltage independently;

wherein, the second fuse is prompted to disable battery powering of the computer system as a back up to the first fuse; and

wherein said control module further acts to;

measure cell voltage when the battery is neither charging nor discharging power to a load; and

responsive to a voltage decrease over a predetermined threshold over a predetermined time period when the battery is neither charging nor discharging power to a load, trigger a third fuse to disable the battery.

2. The apparatus according to claim 1, further comprising:

a battery management unit;

said battery comprising a plurality of cells;

said control module acting to prompt said battery management unit to trigger the first fuse at or above the first voltage associated with the battery over-charge condition per cell.

3. The apparatus according to claim 2, wherein:

said control module further acts to prompt said battery management unit to trigger the second fuse at or above the second voltage associated with the battery over-charge condition per cell.

4. The apparatus according to claim 1, wherein said control module further acts to:

use a first safeguard to prompt disabling battery power to the computer system responsive to a first voltage associated with a battery over-discharge condition; and

use a fuse to redundantly prompt disabling battery power to the computer system responsive to a second voltage associated with the battery over-discharge condition.

5. The apparatus according to claim 4, wherein:

the first safeguard is a discharge FET; and

said control module further acts to prompt a deactivation of said discharge FET at or below the first voltage associated with the battery over-discharge condition per cell.

6. The apparatus according to claim 1, wherein said control module further acts to:

detect taper current associated with battery over-current and detect a specified voltage associated with battery over-current.

7. The apparatus according to claim 1, wherein said control module further acts to:

detect a first temperature associated with battery overheating and detect a second temperature associated with battery overheating;

wherein the second temperature is greater than the first temperature;

wherein, responsive to detection of the first temperature, said control module acts to stop charging of the battery; and

wherein, responsive to detection of the second temperature, said control module acts to disable the battery.

8. The apparatus according to claim 1, wherein:

said control module acts to prompt a disablement of said battery responsive to a voltage imbalance in cell blocks.

9. The apparatus according to claim 1, further comprising a thermal fuse positioned to detect FET failure;

wherein, responsive to an FET failure, the thermal fuse is triggered to disable battery powering.

10. A method comprising:

providing battery power to a computer system;

monitoring a plurality of battery conditions of a battery;

using a first fuse to prompt disabling battery power to the computer system responsive to a first voltage associated with a battery over-charge condition; and

using a second fuse to redundantly prompt disabling battery power to the computer system responsive to a second voltage associated with the battery over-charge condition;

wherein disablement responsive to the first voltage is independent of disablement responsive to the second voltage; and

wherein, the second fuse is prompted to disable battery power to the computer system as a back up to the first fuse;

measuring cell voltage when the battery is neither charging nor discharging power to a load; and

responsive to a voltage decrease over a predetermined threshold over a predetermined time period when the battery is neither charging nor discharging power to a load, triggering a third fuse to disable the battery.

11. The method according to claim 10, further comprising:

using a first safeguard to prompt disabling battery power to the computer system responsive to a first voltage associated with a battery over-discharge condition; and

using a fuse to redundantly prompt disabling battery power to the computer system responsive to a second voltage associated with the battery over-discharge condition.

12. The method according to claim 10, further comprising:

detecting taper current associated with battery over-current; and

detecting a specified voltage associated with battery over current.

13. The method according to claim 10, further comprising:

detecting a first temperature associated with battery overheating; and

detecting a second temperature associated with battery overheating;

wherein the second temperature is greater than the first temperature;

wherein, responsive to detection of the first temperature, battery charging is stopped; and

wherein, responsive to detection of the second temperature, the battery is permanently disabled.

14. The method according to claim 10, wherein a voltage imbalance among different groups of battery cells prompts disablement of the battery.

15. A program storage device readable by machine, tangibly embodying a program of instructions executable by the machine to perform acts comprising:

providing battery power to a computer system;

monitoring a plurality of battery conditions of a battery;

using a first fuse to prompt disabling battery power to the computer system responsive to a first voltage associated with a battery over-charge condition; and

using a second fuse to redundantly prompt disabling battery power to the computer system responsive to a second voltage associated with the battery over-charge condition;

wherein disablement responsive to the first voltage is independent of disablement responsive to the second voltage; and

wherein, the second fuse is prompted to disable battery power to the computer system as a back up to the first fuse;

measuring cell voltage when the battery is neither charging nor discharging power to a load; and

responsive to a voltage decrease over a predetermined threshold over a predetermined time period when the battery is neither charging nor discharging power to a load, triggering a third fuse to disable the battery.

16. An apparatus comprising:

a battery having a plurality of battery cells therein, said battery configured for powering a computer system; and

a control module which controls said battery and monitors a plurality of battery conditions;

said control module being configured to independently use a first fuse and a second fuse for disabling the battery, wherein to independently use a first fuse and a second fuse comprises;

using the first fuse to disable the battery responsive to a first voltage associated with a battery over-charge condition; and

using the second fuse to redundantly and permanently disable the battery responsive to a second voltage associated with the battery over-charge condition; and

wherein, the second fuse is prompted to disable battery power to the computer system as a back up to the first fuse; and

wherein said control module further acts to;

measure cell voltage when the battery is neither charging nor discharging power to a load; and

responsive to a voltage decrease over a predetermined threshold over a predetermined time period when the battery is neither charging nor discharging power to a load, trigger a third fuse to disable the battery.