[ltp] Thinkpad battery exhausted in less than a year?

[ben]

Here's a good link to answer your questions:  http://www.google.com

:)

And just to prove that I can occasionally be useful:
http://www.fact-index.com/l/li/lithium_ion_battery.html

Here's the most interesting paragraph for this discussion:

   Li-ion batteries are not as durable as NiMH and NiCd designs,
   although they do not suffer from the memory effect. At a typical
   100% charge level (notebook battery, full most of the time) at 25
   degrees centigrade, Li-ion batteries irreversibly lose
   approximately 20% capacity per year from the time they are
   manufactured, even when unused. (6% at 0 degrees, 20% at 25
   degrees, 35% at 40 degrees centigrade. When stored at 40% charge
   level, these figures are reduced to 2%, 4%, 15% at 0, 25 and 40
   degrees centigrade respectively.) Every (deep) discharge cycle
   decreases their capacity. The degradation is sloped such that 100
   cycles leave the battery with about 75% to 85% of the
   original. When used in notebook computers or cellular phones, this
   rate of deterioration means that after two to three years the
   battery will have capacities too low to be still usable.

Unfortunately I lost the really good link I had...

I usually keep the battery in the laptop as a backup against
accidental unplugging etc, but if I'm leaving the machine on overnight
in order to run a simulation, I know that the system will get very
hot, and even though the battery will not be used it'll get hot right
along with everything else.  If at all possible, when running big
jobs, remove the battery!!!  Keeping it in the 'fridge is great, but
just keeping it on the desk away from the computer (not in the
direction of the exit fan) is already very helpful.

Note that things like powernowd, spinning down the hard disk, etc,
save power.  If you use more power, where does it go?  It turns into
heat.  Turn on all the powersaving features WHEN THE BATTERY IS IN THE
COMPUTER, even when you're also plugged in to the wall.

(Of course, wasting energy is basically the same as voting for Bush)

If you have a spare battery, discharge it to 40% and stick it in the
fridge (not clear why they should not freeze; I assume that means that
the organic solvent is water-based?).

-- 
Ben Pearre          http://hebb.mit.edu/~ben       PGP: CFDA6CDA
          Free Music at http://hebb.mit.edu/FreeMusic
Don't let Bush read your email!             http://www.gnupg.org