Re: Rechargeable Alkalines

["B Fuhrmann" <b-fuhrmann-usenet@xxxxxxxxxxxxxxxxxxxxxxxxx>]

"Robert Green"  wrote ...
>A short while back we had some discussions about rechargeable alkalines.
> Since it's been at least 10 years that I last tried them, I thought I
> would
> give the "Juice" product sold on Ebay a try in my Nikon Coolpix Battery
> Hog
> 950.  The problem with the camera is that just by sitting a week or so,
> fully charged NEW NiMH cells apparently drop in voltage enough to cause
> the
> camera's LOBATT warning to appear, shutting the camera off.  Testing
> reveals
> the batteries are still nearly fully charged, but it seems that only HOT
> batteries fresh from the charger can be depended upon to work.

I think that it was a function of equipment being designed for the higher
voltage alkaline cells.  I know that there is no "memory" effect with NiMH
cells but there is some sort of problem that can cause them to not recharge
fully.  I have several sets that have some problem that causes them to short
cycle in the GPS and other sets that can sit for a couple weeks and run the
full time.
I have considered doing some sort of battery tester that I can run on cells
to match their capacity.  Just don't have the free time.  It would include
an appropriate load with a timer and voltage sensor so that I can do a
resistive load that is roughly the right current for the GPS and measure how
long till the cell hits 1/2 of the GPS turn off voltage.

> I solved the problem for the even more low-voltage sensitive CoolPix 2100
> with rechargeable LIon's.  NiMH cells would register low battery in just a
> few days of sitting idle.  The LIon cells give me the best of both worlds.
> The camera will still run from common AA's if I am stuck in the field
> without a recharger, but performs *very* nicely now, weeks after a LIon
> pack
> is installed.

Are using CRV3 type batteries?
www.eastcoastphoto.com/nav/itempage.asp?itemid=6055&trng=fgle

If not, what do you use?

The terminals seem to be recessed inside the battery (makes sense
considering what shorting can do to them.


--
Bill Fuhrmann