aaaaa wrote:
I just received a new PA33838U-1BRS (?12 cell I think) battery I
bought from batterydepot.com and I am surprised that it has so short a
life in my Toshiba A75-S209 laptop.

I should say for the record that the battery arrived fully discharged,
dead as could be. That surprised me too.

But then I know nothing about Lithium ION batteries, so I am not sure
what to expect. I have read the info at
http://batteryuniversity.com/learn/a..._ion_batteries

As I watch Toshiba's Power Meter, with the desktop displayed, but the
laptop sitting idle otherwise, the capacity has decreased from 97% to
50%. That says to me that I will get only two hours out of a full
battery charge. Is that normal, good, bad, or what? I also wonder
why an overnight full charge (laptop off) only charged the battery to
98%.

So - I have to ask. Is something wrong? What is normal?

Thank you

Those particular kind of batteries, are like "tomatoes".
You have to buy them "fresh". Check to see if there is a
manufacture date on the battery, to get some idea how
old the stock is. It might be as old as the original
battery for example.

The battery ages, even in storage. They only last a limited period
of time. In fact, it probably doesn't matter how many times you
charge and discharge that battery, as it'll wear out on a time
basis anyway. When you buy one, you might as well use it.
It can't be preserved in any practical way. So buying two
of them, on the premise you'll use them serially, is a mistake
(i.e. start using the second one, when the first wears out, the
second one won't have much life left in it).

The Battery University may claim it lasts the longest in storage,
at 40% charge. If you received your new battery completely flat,
the charger circuit may have refused to charge it. It may have had
some residual voltage on it, and not been completely flat (zero
volts).

You'd need to search for battery life reports for your model
of laptops, under identical conditions. If you Google and
someone has said in the past "my Toshiba XYZ will run
for 3 hours idle in the desktop", that would give you a
metric for comparison. Otherwise, it's pretty hard for
someone who doesn't own such a laptop, to judge.

My new laptop, lasts maybe 2.5 hours on battery. It has a 25W
processor, a single core, so should be easy on the battery.
There are no fancy graphics, only the GPU in the Northbridge.
And my battery is small. It's not an extended runtime battery.

Some other kinds of (gutless) portable computing products,
get ten hours off a single charge. That's sort of the upper
range for portable equipment. A "desktop replacement" laptop,
one with fancy gaming graphics chip, might only get 30 minutes
from battery, due to the heavy electrical load. Such computers
are not really intended for "off tether" operation - they're
really intended to be operated from the mains at all times.
The battery in that case, functions more as a UPS, providing
power to cover short outages if they occur. You couldn't
really do very much, with a 30 minute battery life (like
watch a DVD movie on the plane).

Paul