Battery problems

[Mikkel L. Ellertson]

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On 03/12/2012 03:23 PM, Michael Cronenworth wrote:
> Robert Moskowitz wrote:
>> Now with the new battery, how with Fedora, am I going to run down the
>> battery? I don't see that IBM has a Linux utility for this, oddly
>> enough...
>
> Those types of battery conditioning are no longer required on the
latest lithium ion units. Now... old NiCD are a different story.

It is not for conditioning the battery. It is to update the battery
calibration. I admit that my newest laptop is about 5 years old, but
the user's manual says to do it once a month. It also advises not to
leave the laptop plugged in when not in use. I believe this is
because the charger tends to short cycle the battery charge - once
it gets below 100%, it charges it right away, as compared to the
newer charging circuits that let it drop to 95% before charging.

One thing to keep in mind with lithium batteries is that there is a
chip inside that tells you how much charge the battery has. You can
not base it on battery voltage, because the voltage remains the same
for most of the charge, with a drop at the end of the charge. But as
the battery ages, it does not hold as much of a charge. If you do
not discharge and recharge the battery, the battery condition
circuitry never gets updated with the current battery life.

One other thing I have seen recommended is to remove the battery if
you are going to be running on AC most of the time. You put the
battery back in about once a month to recharge it from storage
losses. It does require that the laptop be able to run without the
battery. I do not know if any current laptops use the battery as a
filter capacitor to keep the supply voltage constant...

Mikkel
- -- 
Do not meddle in the affairs of dragons, for thou art crunchy and
taste good with Ketchup!
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