Battery management system and method for extending time until a battery reaches an over-discharged state during storage of an information handling system

Patent metadata

Field	Value
Publication number	US-10491014-B2
Application number	US-201414331994-A
Country	US
Kind code	B2
Filing date	Jul 15, 2014
Priority date	Jul 15, 2014
Publication date	Nov 26, 2019
Grant date	Nov 26, 2019

Abstract

A computer-implemented method extends the time until the battery reaches an over-discharged state of an information handling system during storage. The method comprises determining if a first battery parameter is outside an associated first battery parameter specification. When the first battery parameter is outside the associated first battery parameter specification, a power management controller isolates the battery by turning off a charge/discharge field effect transistor. The method also includes determining if the first battery parameter is outside an associated second battery parameter specification. In response to the first battery parameter being outside the associated second battery parameter specification, the power management controller is triggered to enter a minimum power state to further reduce power consumption from the battery.

First claim

What is claimed is:

1. A computer implemented method to extend a time until a battery reaches an over-discharged state during storage of an information handling system (IHS), the method comprising:
determining if a first battery parameter is outside an associated first battery parameter specification during storage of the information handling system;
in response to the first battery parameter being outside the associated first battery parameter specification during storage of the information handling system, a power management controller turning off a charge/discharge field effect transistor (FET) to reduce power consumption and extend the time until the battery reaches the over-discharged state, wherein the battery is isolated from the system load by turning off the charge/discharge FET, and wherein after the battery is isolated from the system load, further discharge of the battery is due to power draw from the controller and from self-discharge of the battery;
determining if the first battery parameter is outside an associated second battery parameter specification during the storage of the information handling system;
in response to the first battery parameter being outside the associated second battery parameter specification during storage of the information handling system, triggering the controller to enter into a minimum power state that further reduces power consumption and further extends the time until the battery reaches the over-discharged state, until a trigger condition is detected that provides power to the information handling system;
determining whether the trigger condition has occurred following entry by the controller into the minimum power state, the trigger condition being one of (i) communication occurring on a system management bus (SMBus) in response to power being connected to a power connector, (ii) detection of a depressing of an on/off power switch after the power is connected to the power connector;
in response to the trigger condition, a management controller of the IHS:
exiting the minimum power state and entering an on state; and transmitting a signal on a connecting wire to turn on the charge/discharge FET;

determining if the battery has been disconnected from the information handling system for greater than a first time period;
in response to the battery being disconnected for greater than the first time period, determining if the battery has been reconnected; and
in response to the battery being reconnected, triggering the power management controller to exit the minimum power state and enter an on state.

2. The method of claim 1 , further comprising:
monitoring a first elapsed time after a last detected system management bus communication;
comparing the first elapsed time to a first elapsed time threshold;
in response to the first elapsed time being greater than the first elapsed time threshold, retrieving the first battery parameter;
monitoring a second elapsed time after a last detected system management bus communication;
comparing the second elapsed time to a second elapsed time threshold; and
in response to the second elapsed time being greater than the second elapsed time threshold, triggering the controller to enter the storage mode.

3. The method of claim 1 , wherein the first battery parameter comprises at least one of a battery charge value, a battery capacity value, a battery voltage value and the first elapsed time.

4. The method of claim 1 , wherein the first battery parameter specification comprises at least one of a battery charge threshold, a battery capacity threshold, a battery voltage threshold, a first battery elapsed time threshold, and a second battery elapsed time threshold.

5. The method of claim 1 , further comprising:
determining if another system management bus communication has occurred; and
in response to the other system management bus communication occurring, triggering the power management controller to exit the minimum power state and enter into an on state.

6. The method of claim 1 , further comprising:
determining if a power switch has been cycled; and
in response to the power switch being cycled, triggering the power management controller to exit the minimum power state and enter into an on state.

7. A battery management system for extending a time until a battery reaches an over-discharged state during storage, the battery management system comprising:
a battery;
a charge/discharge field effect transistor coupled to the battery;
a power management controller coupled to the battery and to the charge/discharge field effect transistor (FET), the controller having firmware executing thereon to enable extending the time until the battery reaches the over-discharged state, wherein the firmware configures the controller to:
determine if a first battery parameter is outside an associated first battery parameter specification during storage of an information handling system in which the battery management system exists;
in response to the first battery parameter being outside the associated first battery parameter specification during storage of the information handling system, extend the time until the battery reaches the over-discharged state by turning off the charge/discharge FET to reduce power consumption, wherein the battery is isolated from the system load by turning off the charge/discharge FET, and wherein after the battery is isolated from the system load, further discharge of the battery is due to power draw from the controller and from self-discharge of the battery;
determine if the first battery parameter is outside an associated second battery parameter specification during the storage of the information handling system;
in response to the first battery parameter being outside the associated second battery parameter specification during storage of the information handling system, trigger the controller to further extend the time until the battery reaches an over-discharged state by entering into a minimum power state, which further reduces power consumption, until a trigger condition is detected that provides power to the information handling system;
determining whether the trigger condition has occurred following entry by the controller into the minimum power state, the trigger condition being one of (i) communication occurring on a system management bus (SMBus) in response to power being connected to a power connector, (ii) detection of a depressing of an on/off power switch after the power is connected to the power connector;
in response to the trigger condition, a management controller of the IHS:
exiting the minimum power state and entering an on state; and transmitting a signal on connecting wire to turn on the charge/discharge FET;

determine if the battery has been disconnected from the information handling system for greater than a first time period;
in response to the battery being disconnected for greater than the first time period, determine if the battery has been reconnected; and
in response to the battery being reconnected, trigger the power management controller to exit the minimum power state and enter an on state.

8. The battery management system of claim 7 , wherein the firmware further configures the power management controller to:
monitor a first elapsed time after a last detected system management bus communication;
compare the first elapsed time to a first elapsed time threshold;
in response to the first elapsed time being greater than the first elapsed time threshold, retrieve the first battery parameter;
monitor a second elapsed time after a last detected system management bus communication;
compare the second elapsed time to a second elapsed time threshold; and
in response to the second elapsed time bein

Assignees

• Dell Products Lp

Inventors

• Chang Chia-Fa
• Chang Wen-Yung
• Liang Tun-Chieh
• Thompson Richard C

Classifications

• H02J7/63

  against overdischarge · CPC title

• H02J9/002 Primary

  in which a reserve is maintained in an energy source by disconnecting non-critical loads, e.g. maintaining a reserve of charge in a vehicle battery for starting an engine · CPC title

• H02J7/0029 Primary

  Electricity · mapped topic

• H02J7/0077

  Electricity · mapped topic

• H02J2007/004

  Electricity · mapped topic