Question about batteries

Yahoozy · Jun 12, 2008

ok, so i have two sets of batteries for my camera (by the way my camera takes 4 AA rechargeables) and my usual routine is to charge up one set while using the other.

now, usually theres a bit of overlap here and there when i go out and want a second set as a backup, but at any rate it seems like the batteries dont last nearly as long as they should, usually they crap out about halfway through what im doing so i need to swap them out for another set.

does anyone know some stuff about batteries? like if you charge em too much they dont last as long? or like leaving them out makes them lose a charge?

thanks guys =P

Phazan · Jun 12, 2008

Well what I've been told about them:

-don't leave them sitting for a while uncharged
-don't leave them sitting for months without being used
-when you first get them, drain them completely before you recharge them
-The batteries loose their performance the older they get

That's what I've been told at leased.

dylj · Jun 12, 2008

Rechargeables have a self-discharge rate. Meaning every day, they lose 1-2% of their charge. So you either leave them charging all the time (which might be unhealthy or dangerous, I don't know) or charge them right before you need them.

Yahoozy · Jun 12, 2008

ah cool
*just had a brainwave*
if i leave them in the camera when its off would they drain faster?

RyanLilly · Jun 12, 2008

Yahoozy said:
ah cool
*just had a brainwave*
if i leave them in the camera when its off would they drain faster?

They probably do drain a bit faster in the camera, you should remove them if you don't plan to use your camera for a few days.

usayit · Jun 12, 2008

We have to know whether you are talking about Ni-MH or Lithium-ion batteries. Both have different characteristics, maintenance and life-span.

Yahoozy · Jun 12, 2008

Ni-MH

Big Mike · Jun 12, 2008

NiMh batteries do loose their charge with time. It's probably more than just 1-2% per day. So you should always make sure they are freshly charged.

The aren't supposed to have a 'memory'...meaning that you can charge them without having to fully drain them every time...but I've heard that it's still better to drain them each time if you can.

Also, what type of charger to you use? The cheap 'rapid' chargers can over heat the batteries and shorten their effective capacity...this will also happen over time. So even though they are rated at 2500 mAh...they might only be able to hold 1800 mAh or something like that.

I suggest a charger that has a slow charging rate and that monitors the batteries so they don't get over charged. You can even get a charger that will test the batteries and tell you their effective capacity....and maybe be able to bring them back up with a refresh mode etc.

Yahoozy · Jun 12, 2008

great thanks =P
ill get another charger (slow one's fine with me) so that i can charge both sets at the same time and keep em out of the camera when im not using it

thanks for all the help guys =P

djrichie28 · Jun 12, 2008

Yahoozy said:
like if you charge em too much they dont last as long? or like leaving them out makes them lose a charge?
=P

You bet they do. Rechargeable batteries NI-MH, do in time lose their ability to retain a full charge. They generally last about a year of normal use before needed replacement. They are good for x number of charge cycles.

Dao · Jun 12, 2008

Yahoozy said:
like leaving them out makes them lose a charge?

If that is the main problem, I think you can try the Sanyo Eneloop Rechargeable batteries. And you do not have to use their charger.

http://www.eneloop.info/

bahandi · Jun 12, 2008

i've been told that the Panasonic batteries were made specifically for digital cameras. I don't know anything about them but the sales guy says they lose less charge than the other types.

mrodgers · Jun 12, 2008

What brand?

As a micro RC airplane flier, I've gone through my fair share of AA NiMH batteries. I fly a plane that charges a small (130 mA) Lipo battery from the 6 AA batteries in the radio.

The best NiMH AA batteries I have found are the Rayovac 2500 mah. I've been using them in my RC plane's controller charging the plane's Lipo for 2 years before I bought my camera. I transfered those batteries to usage in the camera when I bought it in December.

I can leave my camera on all day long on a full charge, using the camera all day filling up the 2 gig SD card with about 550 shots (no flash). That is, I have turned the camera on and left it on, picking it up when I wanted to shoot.

With the camera sitting at home and picking it up now and then to use, I can go at least a week before needing to recharge. In fact, the last time I recharged them was Memorial Day morning I think. I've probably taken roughly an average of 10 shots per day since then and the batteries are still charged. Only problem I have is that my camera doesn't have a meter on it. It only pops up a battery icon when they are finished and need recharged.

Again, this is the same set of batteries that I used for 2 years in the RC plane. I would get around 10 uses recharging the Lipo with the NiMH batteries before needing to recharge them. I flew this little plane a LOT.

Another thing about using multiple NiMH batteries. Yes, they don't really have a memory like the old NiCAD batteries did. But, when you use 4 of them such as in a camera, they will become unbalanced from each other from charging them before completely depleted. To balance them, you have to discharge them completely, then the best way would be with a good slow charger that monitors them. But I would imagine the 4-8 hour chargers would be sufficient. The best way to do it is to find out the C rating of the battery (C rating is the recommended charge rate, 1C=charge rate the same as the capacity, or 2.5 amps for a 2500mah battery) and charge it at 1/10th the C rating. I don't know what the C rating of standard AA NiMH batteries are.

I know I have a very extensive link about rechargeable batteries somewhere in my RC links, but I can't find it anywhere.

Dao · Jun 12, 2008

Well, in case you may not know, if you fully change the Eneloop battery and then set it aside for 1 year. It still can hold 85% of the charge vs regular rechargeable battery will loss almost all the charge.

And that is why I recommend the OP to try it out.

MarcusM · Jun 12, 2008

dylj said:
Rechargeables have a self-discharge rate. Meaning every day, they lose 1-2% of their charge. So you either leave them charging all the time (which might be unhealthy or dangerous, I don't know) or charge them right before you need them.

There is now a brand new technology on the market - I don't know much about it other than it is supposed to allow the rechargeable batteries that utilize it to retain about 85% or so of the charge for a full year. (meaning if you buy the battery and it sits on your shelf for a full year before you use it and then you use it, it will be about 85% charged)

I quit buying Energizer rechargeable batteries a while ago after I read this article: http://www.naturalnews.com/PhotoTour_Energizer_Batteries_1.html

I started buying the Powerex batteries the author recommended and I noticed a big difference right away - the Powerex D batteries are way heavier than the Energizer D batteries and do last longer - they are rated at 11,000 mAh while Energizer rechargeable Ds are rated at 2500 mAh! Of course cameras don't take D batteries but I just wanted to make a point. He also states Sony and Sanyo are good.

The Imedion Powerex AA batteries that are offered by the author of the article are rated at 2100 mAh, which is lower now than Energizer AA rechargeables, but the Imedions have the new technology that allows them to retain more of the charge for longer, and the mAh rating will improve as the technology improves.