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Jim,<br>
<br>
Thanks for the note. Based on what you said, I've been searching for
ubuntu battery calibrate in Google. Nothing conclusive yet, but I'll
share whatever I find. I'm going to try a complete discharge and
recharge cycle starting from a full battery, while Linux is running.
The problem is, I don't know if the machine will shut off at the proper
time.<br>
<br>
Below are some links and info I found.<br>
<br>
Sincerely,<br>
<br>
Ron<br>
<br>
----------------------<br>
<br>
<a class="moz-txt-link-freetext" href="http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries">http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries</a><br>
<br>
quote on --><br>
<br>
<font face="Arial, Helvetica, sans-serif" size="2">A lithium-ion
battery provides 300-500 discharge/charge cycles. The battery prefers a
partial rather than a full discharge. Frequent full discharges should
be avoided when possible. Instead, charge the battery more often or use
a larger battery. There is no concern of memory when applying
unscheduled charges.<br>
<br>
Although lithium-ion is memory-free in terms of performance
deterioration, batteries with fuel gauges exhibit what engineers refer
to as "digital memory". Here is the reason: Short discharges with
subsequent recharges do not provide the periodic calibration needed to
synchronize the fuel gauge with the battery's state-of-charge. A
deliberate full discharge and recharge every 30 charges corrects this
problem. Letting the battery run down to the cut-off point in the
equipment will do this. If ignored, the fuel gauge will become
increasingly less accurate. (Read more in 'Choosing the right battery
for portable computing', Part Two.) </font><br>
<br>
<-- quote off<br>
<br>
<br>
quote on --><br>
<br>
<font face="Arial, Helvetica, sans-serif" size="2">The worst condition
is keeping a fully charged battery at elevated temperatures, which is
the case with running laptop batteries. If used on main power, the
battery inside a laptop will only last for 12-18 months. I must hasten
to explain that the pack does not die suddenly but begins with reduced
run-times.</font><br>
<br>
<-- quote off<br>
<br>
<br>
quote on --><br>
<br>
<font face="Arial, Helvetica, sans-serif" size="2">There are no
remedies to restore lithium-ion once worn out</font><br>
<br>
<-- quote off<br>
<br>
<br>
quote on --><br>
<br>
<p> <font face="Arial, Helvetica, sans-serif" size="2"><b>Simple
Guidelines</b></font></p>
<ul>
<li> <font face="Arial, Helvetica, sans-serif" size="2">Avoid
frequent full discharges because this puts additional strain on the
battery. Several partial discharges with frequent recharges are better
for lithium-ion than one deep one. Recharging a partially charged
lithium-ion does not cause harm because there is no memory. (In this
respect, lithium-ion differs from nickel-based batteries.) Short
battery life in a laptop is mainly cause by heat rather than charge /
discharge patterns.</font><br>
</li>
<li> <font face="Arial, Helvetica, sans-serif" size="2">Batteries
with fuel gauge (laptops) should be calibrated by applying a deliberate
full discharge once every 30 charges. Running the pack down in the
equipment does this. If ignored, the fuel gauge will become
increasingly less accurate and in some cases cut off the device
prematurely. </font><br>
</li>
<li> <font face="Arial, Helvetica, sans-serif" size="2">Keep the
lithium-ion battery cool. Avoid a hot car. For prolonged storage, keep
the battery at a 40% charge level. </font><br>
</li>
<li> <font face="Arial, Helvetica, sans-serif" size="2">Consider
removing the battery from a laptop when running on fixed power. (Some
laptop manufacturers are concerned about dust and moisture accumulating
inside the battery casing.)</font><br>
</li>
<li> <font face="Arial, Helvetica, sans-serif" size="2">Avoid
purchasing spare lithium-ion batteries for later use. Observe
manufacturing dates. Do not buy old stock, even if sold at clearance
prices. </font><br>
</li>
<li> <font face="Arial, Helvetica, sans-serif" size="2">If you have
a spare lithium-ion battery, use one to the fullest and keep the other
cool by placing it in the refrigerator. Do not freeze the battery. For
best results, store the battery at 40% state-of-charge.</font></li>
</ul>
<br>
<-- quote off<br>
<br>
<br>
On 02/18/2011 02:44 PM, Jim Kinney wrote:
<blockquote
cite="mid:AANLkTi=1Lan6E=Spf7YvGhhvX5TX4q2wuxwKJydSC+ru@mail.gmail.com"
type="cite">
<pre wrap="">Don't recall details but I think there's a way to calibrate the
battery monitoring app. It involves running down the battery a bit and
recharging for a while and making calculations from that. Not finding
how on a quick google search.
On Fri, Feb 18, 2011 at 11:41 AM, Ron Frazier
<a class="moz-txt-link-rfc2396E" href="mailto:atllinuxenthinfo@c3energy.com"><atllinuxenthinfo@c3energy.com></a> wrote:
</pre>
<blockquote type="cite">
<pre wrap="">I'm running Ubuntu 10.04. I have the Gnome power management icon set to
display all the time on my laptop. If I left click the icon, I get two
lines on a menu. The bottom, preferences, lets me set the power
management preferences. The top line says Laptop battery is charged (at
the moment). However, you can click on that line. When you do, you get
a detailed statistics screen. You can click on the ac adapter, the
battery, or the processor. If I click on the laptop battery section,
then the details tab, I get lots of info about the battery. It says the
capacity of the battery is 57.7 %, but the current percentage is 100%.
I've noticed sometimes that, when the battery is discharged, and I let
it charge back up while Linux is running, it stops charging at this 57 %
level. However, if I shut down Linux and let the computer charge the
battery while the machine is off. It fully charges. I think Linux is
confused.
So, my questions are:
1) How does Linux get it's numbers, from the battery itself, or from
calculations within the program?
2) How do I make Linux forget what it thinks it knows and recalculate so
my battery can fully charge? Windows seems to sense the battery's
charge level fine.
3) Gnome power manager defaults to shutting down the pc at 1% of battery
remaining. I can only tell it what to do at a critical battery level,
not what the level is. For this machine, this is only 1 minute, barely
enough time to shut down. For another machine (with a UPS), that is
only a few seconds, and would probably crash the machine. I need to
know how to set the levels of charge where the warning appears, and
where the shutdown or hibernate happens. I'd prefer not to have to load
another power management program if possible.
Any help would be greatly appreciated.
Sincerely,
Ron
</pre>
</blockquote>
</blockquote>
<br>
<pre class="moz-signature" cols="72">--
(PS - If you email me and don't get a quick response, you might want to
call on the phone. I get about 300 emails per day from alternate energy
mailing lists and such. I don't always see new messages very quickly.)
Ron Frazier
770-205-9422 (O) Leave a message.
linuxdude AT c3energy.com
</pre>
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