#8542 LOW Opportu: Perhaps flash red battery LED for final minutes before blackout.

[Zarro Boogs per Child]

#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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