Originally Posted by CA1200
I find that on a trip it is best to have a camera that runs on AA batterys. Yes I run recharables, but in a situation I have the ability to go anywhere for new batterys if necessary. The only problem I am having is that I own so many rechargables that I can't detect which one, or ones, are going bad. What? What I mean is that my camera takes 4 batterys andthere are times when i will load it and it will not last as long as other times. So I know there is at least one battery or more in my bunch of 12 that is not as good as the others but i can't figure which one. The problem is that rechargables all read good after charging on a volt meter. There is no good, better, best. They all read the same voltage if charged (and holding any charge) but we do not know how long they will last.
Anybody have a way to check 'staying power' on rechargables?
I can help you a bit on this. First I agree with you about using an AA format battery, you can always usually pickup Alkalines in shops. However I think salvation is on its way for hiking and bike trips. There's an emerging new range of non-rechargeable Lithium AA's that claims they last 7 times longer than alkaline. Lithium can last 10 years in storage and don't have the self draining of other battery types (although proprietary LiIon as used in cells isn't bad.)
My wife keeps a camera in her handbag, she probably stores it more than she uses it and doesn't think some batteries need charging. This is an ideal case for AA Lithium. I recently tried 4 of these in my camera and it was half the weight! These batteries are very light.
Here's a link from our side of the pond. The price is dropping, search fleabay.
OK, so now you want to know the inside story on NiMh re-chargeables? First, some cameras are designed for a 1.5 volt AA batteries. Most re-chargeables will make 1.35 volt per AA cell just off the charger but fall back within an hour to about 1.25. The battery may have the current capacity (mA hours) it says on the pack, BUT the camera battery voltage sensing is already thinking the battery has lost a lot of charge. This is unfortunate because some cameras decide to put up a low battery warning and shut down far to soon with re-chargeables. This means you can probably only use 75% of the battery capacity. I have never seen a camera that can tell or allow you to select re-chargeable or non-rechargeable batteries. So there's a myth: a 1.5 volt Alkaline battery may actually last longer than some lower voltage re-chargeables. Now the new AA Lithiums are 1.5 volt so that's a winner. If you have ever tried using re-chargeables in a flash gun you have the same voltage problem. Non re-chargeables can work better and last longer.
Now the chargers: The cheaper chargers that take 4 batteries may only have one charge controller circuit and charge 4 batteries in series. The problem there is some batteries in the group may never be fully charged when the charger shuts off, conversely some batteries can be overcharged. If your charger has a switch for charging 2 batteries, then it probably has only 1 or 2 regulators. I only buy the 4 battery chargers that have 4 separate charging circuits and a led for each battery which can go to green at different times.
Most chargers have a low current trickle at end of charge. I always leave my batteries in my automatic charger after they finished charging and grab them when I use the camera. I keep the camera stored when not in use with AA dry or the new Lithiums so it doesn't forget date/time and user settings. Like many, I have about 20 re-chargeable AA batteries now and I get fed up with another bad characteristic which is self-discharge - they go flat when not in use. I shall be making a simple trickle charger that can put a very small safe current through all of them 24/7 once they've been fully charged. You can read various pros and cons about doing this and battery life, but I'd consider NiMh re-chargeables not much good after a couple of years anyway.
Many 4 battery chargers come with a 12 volt to cigar plug lead. Replace their car plug with a BMW accessory connector and you're hot to go.
Checking the 'staying power' or battery capacity as you put it is fraught with claims and counter claims. As I said, your camera may not like the lower voltage and shut down early when there is still some reasonable capacity left in the battery. It's a good idea to fully re-charge a re-chargeable and then fully discharge it. Unfortunately you can't do this in the camera because it shuts off - kids toys or a small bulb/resistor can do that. Knowing the capacity or 'goodness' of batteries used in groups is important because if 1 battery is bad, the camera thinks all 4 are bad. The only way to find out is to fully charge the battery with an individual regulator type charger then put a small bulb on it and time how long it stays lit. That's a bit crude but will give you an idea which cells are worse than others. Repeat the charging on the poorer cells and they may recover their health.
Now for temperature. Most batteries work best when warm (chemical reaction) and the charge you get out will be larger when they are warm so transfer them to your pocket from camera just before use, if the camera was left in the trunk overnight.
Never pay again for live sex! | Hot girls doing naughty stuff for free! | Chat for free!