From: Chris Holt <amiga2k_at_cox.net>
Date: Sun, 4 May 2003 12:48:01 -0400

On Sun, 4 May 2003 03:21:23 +0200, Paul van der Heu wrote:
>http://www.dpreview.com/news/0305/03050204maha2200mah.asp
>

I plan to keep an eye on Dave Etchells' "Great Battery Shoothout" page
http://www.imaging-resource.com/ACCS/BATTS/BATTS.HTM

While Maha apparently is one of the leaders and hasn't made any major
mistakes so far, other manufacturers have created high Mah rated cells at
the expense of fragility. To quote from the above page:

"As I mentioned earlier, the new iPowerUS 2100 mAh cells were a
significant disappointment. They do initially deliver very high power
capacity (the highest I've seen to date, as much as 9.6 watt-hours), but
a tradeoff seems to have been made in their construction that results in
these cells being very delicate. - That is, while they deliver high
capacity at the outset, they can very easily be "killed" by any of a
number of means, including too-high current drain on an intermittent
basis, relatively modest current drain on a continuous basis, or too-long
trickle charging. My standard test setup subjects batteries to a
continuous load of roughly 5 ohms, corresponding to the current drain of
a rather high-drain digicam. This is the condition I test all cells
under, and other NiMH cells tolerate it quite well, but it resulted in
the iPowerUS 2100s losing capacity with every charge/discharge cycle.
Through Thomas Distributing (the source of the cells I tested), I was
told that iPowerUS had designed these cells"specifically for digicams,"
which apparently meant that they were designed to be used in an
intermittent fashion. iPowerUS claims that these cells can tolerate high
drain currents only in intermittent usage, but that they should have no
problems with continuous drain under more intermittent usage. In
practice, I found that the highest current drain that the iPowerUS cells
could tolerate without damage was something on the order of 500 mAh or
less."

The above sounds to me like the iPower cells would die a quick death in
the Archos. Dave's tests will tell us about the newer cells from Maha
and others.
I personally don't want to spend about 20 bucks on disposable batteries!
:-O

Chris
Received on 2003-05-04