This is a good article, but its technical scope is quite shallow and maybe
naive because of that.  The author seems honest and competent, but he
doesn't say quite enough about the limitations of his observations.  I think
most of his conclusions are suspect even for the digital cameras he used as
load models.

Read carefully: he says that battery performance, and his tests, are highly
dependent upon the discharge profile and whether its details are mostly high
current or low trickle, etc.  It appears that he is testing only fresh
batteries, and not including mid life or near end life batteries as well.
He is not testing shelf storage charge decay, and he is not testing the
voltage fall-off curves at any point in battery life, let alone mid life and
latter life.

The results that new, premium rechargeables have some advantages over
throw-aways may be valid for the case of very new batteries taken directly
from a charger and put to use.  I doubt that the results would be so pretty
for mid-life charged spare batteries kept in reserve and carried in luggage
at 80-90F during vacation travel.  Discharge curves also change somewhat
with battery age.  The alkalines and the rechargeables have a fairly flat
discharge with sharp drop off near end-of-a-charge.  The cheaper one-shot
LeClanche type cells have an almost straight line voltage drop-off curve
over discharge which is a headache for voltage regulation in electronics and
for "things with motor-like" loads like portable cassette players or
recorders.  Although the voltage may drop below the operating point of your
favorite toy, the ampere-hour rating may not tell this: your toy may require
the voltage per cell to remain above say 1.18 volts for it to operate.  A
LeClanche cell is likely to fall below such a mark within the first 25% of
its actual ampere-hour rating.  This is why the alkaline batteries have
become so popular even for flashlights.

My requirements for batteries for either personal or for professional design
usage go much beyond what this author has considered.  FYI, I chose a Palm
IIIxe when color and rechargeables were available in newer models: I get
full compatibility in B&W, and almost 2 weeks battery life on regular
Duracells.  The rechargeable B&W Palm compatibles show only about 6 hours of
operation between recharges, and that's barely enough for a flight to CA
with a layover.  Rechargeables in a PDA can't be instantly replaced anywhere
or bought in any airport.  Color models are worse.  Pocket PC models are
really terrible.  A B&W Palm is a very low power demand on standby and much
lower than color models when operating.  My digital camera is pretty greedy
of power, but I like the feature of knowing that a fresh set of throw-aways
will assure an operating period  while rechargeables may be "tired" due to
heat or shelf storage and thus may quit prematurely.  I know the
rechargeables cost more than throw-away Duracells, but I do not know that
rechargeables can be as good or better for either 1) typical realistic life
of a spare set, or 2) realistic lifetime cost that includes aging and
storage effects.  I remain skeptical, but YMMV.  Spare throw-aways assure
that precious camera shot the author speaks about, but spare rechargeables
may not.


> -----Original Message-----
> From: tclug-list-admin at mn-linux.org
> [mailto:tclug-list-admin at mn-linux.org]On Behalf Of Michael Vieths
>
>
> There's a really good battery shootout here:
>
> http://www.imaging-resource.com/ACCS/BATTS/BATTS.HTM
>
> It popped up on http://www.arstechnica.com a while back.
>
> --
> Michael Vieths
> Foeclan at Visi.com
>
> On Thu, 5 Sep 2002, Jim Crumley wrote:
>
> > On Thu, Sep 05, 2002 at 12:00:38PM -0500, Chuck Cole wrote:
> > > You probably will get better lifetime and better cost
> from good throw-away
> > > batteries like Duracells.  Rechargeable would be a real
> nuisance for me on a
> > > vacation trip.
> >
> > Huh? Have you tried rechargeable batteries lately? Sure you
> > probably get lifetime out quality disposable batteries than
> > lower end rechargeables, but metal-based rechargeables last
> > _longer_ in digital cameras and the like [1].
>



---
Chuck Cole


  Buying the right computer and getting it to work properly is no more
complicated than
    building a nuclear reactor from wristwatch parts in a darkened room
using only your teeth.
                                                                            
  - Dave Barry

TCLUG Note: OuchLook to be replaced when Linmodem problems solved.
  Have HP driver and info from France, need to patch for 7.3

TCWUG Note: Then comes setup of the built-in Lan Express 802.11b