Dikdik Loc: Winnipeg, Canada

Not likely... the discharge would likely be reduced by means of a diode, and, even they have a high resistance to eliminating discharge; they do not provide a complete 'break'. It is unlikely that the circuit would provide an electronic on/off 'switch'.

Dik

GrandmaG Loc: Flat Rock, MI

Hmm, I have always left the battery in the charger after charging is complete. Perhaps I should reconsider that practice. For the Nikon batteries, there is no significant change between two batteries charged at the same time, leaving one in the charger and one out of the charger when checked weeks later. Sony batteries seem to discharge faster no matter if they are in the camera, in the charger, or not. I’m going to test this out!

The OP provided a thought-provoking post!

GrandmaG Loc: Flat Rock, MI

What do you mean by SWAG? Google didn’t define it!

Dikdik Loc: Winnipeg, Canada

I've always removed the batteries from the charger when they are charged; I'm not sure why... just habit. I've never thought about it.

I don't think my Powerex charger has been unplugged for the last few years, even if there are no batteries in it. It's plugged in all the time.

Dik

Dikdik Loc: Winnipeg, Canada

Simple Wild Assed Guess.

Dik

BebuLamar

It depends on the design of the charger. The power from the battery may go back into the unplug changer and dissipate in the charger.

Dikdik Loc: Winnipeg, Canada

Not trying to hyjack the thread, but, a few months back someone mentioned Ikea's rechargeable batteries... I picked up a dozen AAAs, and they are great. Thanks.

Dik

Dikdik Loc: Winnipeg, Canada

Most chargers are a small step down transformer to reduce the voltage from 110 VAC to 1.5 VAC (give or take) and a rectifier circuit to change the AC to DC. There may be a bunch of other electrical circuitry added to it.

There is a complete circuit from one battery charging terminal to the other; there is no break in the circuit. It is likely high resistance, but a complete circuit nonetheless. This is the source of the current drain (aka battery discharge).

Dik

Traveller_Jeff

Call the manufacturer and ask to speak to one of their technicians. They will give you a definitive answer.

peterg Loc: Santa Rosa, CA

An ohmmeter across the terminals on all four of my camera battery chargers shows high resistence, not an open circuit. Thus, I suspect a battery would slowly discharge if left in any of those unplugged chargers.

rond-photography Loc: Connecticut

I suspect it may. When I plug in my NiMh charger with batteries that I know were fully charged when unplugged, it always needs to charge them. I have not done a controlled test where I put 8 batteries fresh out of the charger aside and then leave 8 fully charged ones in an unplugged charger to see if it is the charger or just the nature of the beast(s). Might do that, but for now, I just make sure I top them off before a shoot.
Lithium Ion batteries are usually fine either way (in unplugged charger or not). I still top them off before a shoot as well, but usually the ones sitting in my spare bag are either already charged, or only take a few minutes before they are topped off.
I figure a few extra batteries are lighter than 20 or 30 rolls of film, and since my "film" in the digital world is of negligible weight, I figure a few extra batteries is cheap insurance against missing some shots. Have had only minor issues with the after market batteries available for my Olympus (2 out of 20 have prematurely failed) over the last 10 years, so it I just buy a few extra.

BebuLamar

Many of the new changers don't use step down transformer any more but use the switching technique to reduce the voltage. They also have current control circuitry to control the charge current as Li -Ion battery is quite finicky to charge. So the final stage of the charger might not be a simple diode or diode bridge and the possibility of having the battery supply current back to the charger is quite possible.

Dikdik Loc: Winnipeg, Canada

Correct... thanks

Dik

rook2c4 Loc: Philadelphia, PA USA

Why bother the technician with such fiddle faddle when you can simply try it out for yourself? Just leave the fully charged battery in the unplugged charger for a period, then remove it and measure the remaining charge. You will then have your definitive answer. Not that the answer really matters.

Paleface

I going to say yes, you have a positive and a negative termal pushing a flat conductive plate, that going to draw juice it will take a while but it will kill it