While it's not exactly survival oriented, this is by far the friendliest of the forums I haunt, so I'll ask here:

I have a digital camera that runs on 2 AA's. It frequently sits for a couple of weeks or more between uses, and I'm tired of picking it up and finding the batteries dead. There is apparently some trickle drain, even when it's off.

I'm thinking of using 2 pairs of some kind of rechargeable, and keeping the batteries next to it on the shelf between uses. If I'm taking it with me, I'd pop them in for the duration. And I'd always have a fresh pair available.

It has a memory card for pictures, so I'm not worried about losing them with no batteries in the camera. I don't use the "date in picture" feature, so I don't care if the internal clock is current.

The different kinds of batteries available today just leave me confused as to which is best for this particular usage. Your thoughts?

For occasional use like that you want low self discharge NiMH. Sanyo Eneloop, Rayovac Hybrid, Maha Imedion, etc. I use those with all my gear, one set in the camera, gps, etc, the other ready to go.
I would try with a set of them in and see if it still drains, sometimes drain is caused by the batteries internal resistance rather than the device itsself.
Also remember a decent charger, most of the ones you find in box stores are crap, the powerex maha, or lacross are the best.
Between the wife and kids and I we have 4 digicams, two GPSs, two way radios, and various other battery powered toys. I use eneloops in all the primary gear such as our GPS's, scanner, etc and the maha in the kids cameras and good toys, nintendo wii remotes, etc (the maha seem to be just as good as eneloop, I just use the black and white batteries to tell them apart.
I have two chargers, a maha c401fs and a maha c9000. About once a year I'll run a test on the batteries with the refresh cycle on the c9000 to see how they are holding up.

+1.

Sanyo Eneloops seem to be the best performers.

I also have a bunch of Duracell Pre-Charged Rechargeables and they seem excellent. HINT: if possible, buy the white-tops (made in Japan) as opposed to the black-tops (made in China). You'll get better performance.

I can't overstate the importance of a good charger. I'm having really good results from the Duracell Mobile Charger CEF23DX4N (got advice from CPF). Individual charging channels, 12VDC or 110VAC operation, and it won't cook your batteries. I was even able to bring a bunch of old Energizer 2500s back from the dead with this charger. You can find them on sale for under $20.

I just bought a simple digital camera not that long ago, too. Most these days seem to use their own proprietary rechargeable lithium ion battery pack. I specifically got it because it takes AA batteries since any lithium ion battery has a fairly finite lifespan and I will likely not need to buy another digital camera for quite a few years, and that style of battery pack may not even be available at that point. But I digress.

Well, the first part of the solution definitely would be to store the camera with the batteries removed.

However, depending on how much you use your camera and how often, let me toss out another option to going the rechargeable route. Besides the excellent suggestion to use a good quality rechargeable NiMH like the Sanyo Eneloop, another option would be lithium AA's, like the Energizer e2. High performance, long shelf life. Can be expensive if you buy them at the drug store, but much more reasonable if purchased online.

Actually, so far, I'm totally fine just using alkaline AA's and just making sure I remove the batteries in between uses. That one thing could be all you need to do.

Good luck!

Ditto on the Sanyo Eneloops -- I use these in the external flash for my Nikon D90.

:-)

Thank you all! Lots of good info!

Consumers Reports recently (December , 2009, I believe) did controlled testing of lithium, rechargeable, and alkaline batteries in cameras. The results were that, on a per picture basis, lithiums were cheaper to use than all but one brand of alkalines. Rechargeable Eneloops were cheaper still. The exception were Costco alkaline AA (Kirkland) bought at 11 cents per battery.

I would much prefer to use lithium or rechargeable units, and have the ability to leave the batteries in the camera, ready for quick use. No way am I putting alkaline batteries in anything of any real value to me.

I ran our 'big' camera on Lithium before, ~500 pictures. Tried Eneloops "fresh" out of the package and got 450 shots. The date code on them they had been sitting for 9 months.

I would try the camera stored with decent batteries in and see if they work. Even though you may not care about the date/time now you may years later, not just the ugly yellow numbers they make to mimic crappy film but the pictures themselves have the date and time (as well as a lot of other info) stored in data fields on them. I was given pictures of mine from when I was young and my parents can't remember which year they were taken even.

What I don't like about the Energizer USB charger is that many were were shipped with a Trojan that if plugged into a Windows pc can allow the pc to be vulnerable to unauthorized remote system access.

Also and in general, the self discharge rate on the these types of NiMH batteries are fairly high and it is not uncommon to see the charge drop by 30% or more per month if the batteries are not being used.

In comparison, Eneloop batteries have a very low self discharge rate and can maintain upwards of a 85% charge rate over several months.

If you are the type who constantly uses and recharges batteries on a regular basis then traditional NiMH batteries will suffice. On the other hand, if you don't have the need to recharge constantly and are looking for long term, low self discharge rates then Eneloops (or other similar types) are the way to go. Nowadays, there is little or no price difference between the 2 types so I stick with Eneloops.

On a related note, I have about 15 NiMH batteries in mostly AA size and a few AAA also. There is a mix of brands: Energizer, Rayovac and Panasonics ranging from 2000mAh to 2600mAh

These batteries have had little or no use and or charges/discharges. I am willing to give them away for free and will ship them at no cost, preferably within Canada to anyone who has a use for them. PM me if anyone is interested.

PM sent.

Re: having the date stamp in the file data:

That's an excellent point, but the only thing I shoot right now is my cat. If I end up with the "store it with the batteries removed" plan, putting them in and setting the date would be part of taking the camera with me.

Just like buying fresh film and batteries used to be for my 35mm SLR.


I'm going to try a good pair of Eneloops (and a good charger) and see how long they last in the turned off camera.


Thanks again, to all!

Enerloops no question.
You can often pick up packs of 2xAA for $10 on sale, either REI or DELL.
Charge them slowly in a regular NiMH charger, they store for months fully charged.

Quick charging (1-2 hours) does not harm them, but neither does slow charge. The important thing is that each battery is monitored individually for temperature and charge status.


Many slow charger nimh will just continue with a slow charge (trickle charge) on the full batteries until you get fed up and remove them. Far from optimal in the long term, little damage in the short term. Most quick charger will PROBABLY have proper monitoring of the batteries because otherwise you'd risk ruining the batteries pretty quickly, a sure way of getting lots of customers complaints on the chargers. On the flip side, a slow trickle charge without monitoring anything at all is a malpractice you could do lots of times before long time effects come into play. For this reason I'd put more confidence in a quick charger than a slow one.


Stay away from chargers that require that you charge in pairs (2 or 4 batteries at a time, but not 1 or 3). If one cell is more depleted than the other you really, really want that cell to be charged for a longer time than its neighbor. If not you'll never get full capacity from that cell.

IIRC ... pride cometh before the fall ...

Thats actually a high price, I usually pay $12 for 4 AA's.

If you insist on rechargeables, NiMH are the way to go. The self discharge rate is pretty low.

For the amount I use my camera, the expensive (lithium) batteries make a lot of sense. They cost 3 or 4X, but last 10X. I am never going back to mere alkaline batteries. And very little in the way of self discharge.

Any advise as to the best source and brand for Lithium AA's in the US?

If you insist on lithium, find someone with a sams club membership, they have IIRC a 20 pack for $12 of the energizer.

What does a battery charger have to do with a computer?

The charger uses the pc usb ports for power. This in turn allows the batteries to be charged.

Is that USB charger smart or just a simple trickle charger?

Eugene: I am not sure whether it is a smart charger or a trickle charger. The only way I found about the Trojan in the software was through some people talking about it at work.

I would guess from size that it may not be all that smart as they can't fit much in there.

I run linux so no worry about trojans here either.

I agree with everything you wrote. I'd add that with normal NiMH, the higher the battery capacity the shorter the shelf-life. This is affected by quality too, of course, but if you've got some fantastic high capacity 3,000 mAh batteries they'll probably have a very high self-discharge rate. Eneloops work largely by being high quality and then trading off some capacity for lower self-discharge.

Picked up a Duracell charger with four AA NiMH batteries. I searched until I found one that said "charges 1 to 4 batteries". It's the one that says "15 minute fast charge", and that it shuts off completely when the batteries are charged.

They all came out of the box with a hair over 1.5v (I have an "inexpensive" analog multimeter). I love that rechargeables now come pre-charged.

I put a pair in the camera, put everything else away, and we'll see what happens.

Thanks again to all!

The low self discharge (LSD) batteries are a different internal structure - they aren't just good quality NiMH.
You get much lower self discharge but at the cost of 20-25% less capacity, however they keep the same output voltage for longer so if your device has a high 'low battery' voltage they may last longer.

Their initial output voltage isn't much different from NiMH - your measurement of 1.5V is faulty because the extreme high input impedance on a DVM means you are mostly measuring stray charge on the terminals, run them for a minute and it will measure 1.2V or so.

If you're shopping for them the original Duracells marked 'made in Japan' are repackaged Sanyo Eneloops.

ps. my earlier post it was 4xAA for $10 in Dell's sale - I forgot I put the other two in my GPS

I've had great luck with the eneloops.