[SATLUG] laptop batteries

Samuel Leon satlug at net153.net
Thu Mar 26 22:42:58 CDT 2009

Borries Demeler wrote:
> I have a question about laptop batteries.
> I have an inspiron 9400 (made by Dell), which is now a couple of years
> old, but works beautifully. It has a dual-core 1.6 GHZ Intel chipset.
> I have 2 batteries for it, which I always recharge fully after use and
> take out of the machine and store when not in use. I never leave the
> batteries in the laptop while the AC power is connected after they are
> recharged for fear that I may decrease the battery's life.
> My question is: Am I unnecessarily paranoid about overcharging the
> batteries, and could I rely on the electronics to automatically shut
> off charging when full in this newer laptop (running slackware 12.2)?
> My experience with older laptops has been that batteries never lasted 2
> years when left in the laptop all the time, but these are still pretty good,
> and last about 1.5-2 hours, when they were new they lasted about 2.5 hours.
> Is that because I take the batteries out when they are full, or
> is that unnecessary? I notice that the KLaptop applet from KDE reduces
> charging when it gets close to full, and then quits charging when 100%
> full (I assume this is true because of the way the charging light first
> comes on only sporadically and finally turns off completely when 100%
> charging state has been reached).
> Any insights on how to extend battery life on these types of laptops
> would be most welcome!
> Thanks,
> -Borries


If I remember right the best way to deal with lith-ion is to store the 
batteries at 40% charge.  Like when I take my laptop to school, once I 
get home I plug the laptop in but pull the battery until I will need it 
next time.  Then I will put it back in a few hours before I leave to let 
it charge up.  But I rarely use my laptop.  It sits on top of my dresser 
for months at a time.

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