#8542 LOW Opportu: Perhaps flash red battery LED for final minutes before blackout.
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Sat Feb 28 15:15:44 EST 2009
#8542: Perhaps flash red battery LED for final minutes before blackout.
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Reporter: thomaswamm | Owner: cjb
Type: enhancement | Status: closed
Priority: low | Milestone: Opportunity
Component: power manager (OHM) | Version: not specified
Resolution: wontfix | Keywords:
Next_action: communicate | Verified: 0
Deployment_affected: | Blockedby:
Blocking: |
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Changes (by rsmith):
* status: new => closed
* resolution: => wontfix
Comment:
see #5858. Thats been there since July of 2008 just not noticed so much
now that we have a handle on the charge balance problem.
Since I added that feature I've build a large archive of olp-pwr-log
files. Based on processing those files the current setting of 5.7V gives
you a range of .7 to 5 minutes of warning time. If I increase that to
5.75 I get 1.5 to 6, and moving to 5.8V I get 1.7 to 9.
At that stage in the discharge cycle things vary wildly based on load and
temperature. You can't predict it much better without a known profile of
your battery at the current operating temperature.
The warning is not suitable for general use but more as an early indicator
for cases where the SOC is out of sync with the real stat of the battery.
This happens due to self-discharge during storage and from charge balance
problems.
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Ticket URL: <http://dev.laptop.org/ticket/8542#comment:2>
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