Kevin wrote in
:

On Fri, 6 Nov 2009 16:52:21 -0600, "Leon"
wrote:


MY BOSCH battery has no such charge indicator. Additionally when the
Li battery decides to be empty, it is empty. It gives you the warning
that it is about to be completely depleted when it slows down half way
through driving "a" 2" screw. It does not completely drive the screw,
it just slows down and stops, on that screw. That's it. With the
NiMH you typically get a warning several screws before depletion.

That's because NiMH loses voltage as it loses charge, but Li-ion
maintains a steadier voltage and then dies. It's really just a
voltage reading of the battery.

My cameras are like that. They have a 3 position battery status
indicator, which loosely translate to full, you need a new battery,
and you will never actually see this unless you happen to be looking
right at it in the 2 seconds it shows before the camera dies.


-Kevin

Rechargable Lithium (not to be confused with Lithium batteries that
aren't rechargable) can be damaged by extreme discharge, so most of them
contain circuitry to shut down the battery when the voltage drops below a
certain point. They also have a tendency to lose capacity whether you
use them or not, so that means after several years they won't hold a
charge worth anything.

LiON batteries are just another option (and should not be the only one)
in the battery game. They've got some serious drawbacks that need
addressed before switching over completely.

Puckdropper
--
"There is no single development, in either technology or management
technique, which by itself promises even one order-of-magnitude
improvement within a decade in productivity, in reliability, in
simplicity."
Frederick P. Brooks, Jr.