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 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.
The alkaline rechargeables didn't fare so well in the Nikon 950. They don't quite have the power of NiMH cells, 2500MAh compared to 2000, IIRC, and that means they give fewer pictures per cell by what you might expect. My first test of longevity wasn't good, either, but it may very well be that the camera drains more power when idle than I've estimated. I'm not sure I'll be able to measure that drain easily, either, so the first tests have a big 'X' factor as a result.
I'm going to recharge them again and try again first with the "Juice" alkalines, then with some Ultra brand hi-capacity NiMH cells. I'm also going to set one of each aside after a full charge, with no load, to test their voltage from week to week. That's a problem because voltage doesn't really tell you much about the state of a battery. At the end of three months (which is where I find drop off in NiMH to begin in earnest) I'll put them in my test rig to see how long they last.
I've set up my RatShack meter to monitor the voltage as the batteries discharge while they power a small incandescent lamp. Not the best test of capacity, but the RatShack PC monitoring software creates interesting discharge curves. The alkalines start at a much higher voltage than the NiMH, but they fall off rapidly more rapidly than I expected at the very beginning of the curve. I'm going to try to post screenprints somewhere since I told the vendor I'd give him feedback.
One place where they absolutely shine is my new Oral-B toothbrush which runs from a single AA cell. The higher initial voltage of the alkaline gives far superior performance in terms of vibration and rotational speed of the brush. I've recharged one of them ten times now, just to see how rechargeable they really are, and there's been a little loss of capacity after each cycle, but not much.
Now that I have the fast charger (with a nice green "charged" indicator) I will probably get more if they can hold their charge substantially longer than NiMH cells. I'm also hoping the Juice cells won't leak as often as regular alkalines. I'm running into more and more leakage issues with Everleaky and Leak-O-Vac cells. I also notice they don't print a guarantee to repair or replace any device damaged, at least on their AA cells, like they used to. I used some GE/Sanyo alkalines in my MP3 player and they leaked so badly they blew off the battery door!!! After I extract them, I'm mailing it to them to see if THEY repair or replace items damaged by their product.
-- Bobby G.