Disposable batteries that aren't going to be used for a long time should be stored in the fridge.
(The low temp slows the loss of energy. Should warm the batteries in your hand or pocket before use). At 100 degrees they lose 25% per year. In a cooler place it is not necessary to put them in a fridge.
Rechargable batteries can regenerate 5 to 10% of their power each day just by sitting there.
Almost flat batteries? Tap up and down all around the casing with ie. pliers and you will shake up the chemicals inside and get another 20 to 40% of more usage. Do not tap really hard or you could break the carbon rod inside.
Disposable AA Alkalines give 1.5 volts, while AA rechargables commonly give 1.2 to 1.3 volts. (hence why lots of instruction booklets recommend using Alkalines, and not rechargables.)
Wiring batteries in Series (postive to negative, and negative to postive) adds the voltage together. ie. AA + AA = 3v
Wiring batteries in Parallel (positive to positive points, and negative to negatives) does not change the voltage: ie. AA + AA = 1.5v
Disposable / throw away Alkaline batteries CAN be recharged with a special green charger. (very cool)
mA-h refers to the capacity of a battery. (How much juice is inside and how long it would last).
Some batteries, when you peel them apart with pliers don't have chemicals inside, they actually have smaller usable batteries inside! ( example: the Energizer A23 - 12 volt - is full of 8 button batteries)
If you make the correct voltage with disposable batteries, it is easy to wire them up to recharge your mobile phone, gameboy etc.
Battery capacity ratings are meaningless when used to compare different types of batteries or to compare the capacity of batteries powering different types of devices.
This means that you may not be able to predict how long your electronic device will run just by looking at the capacity rating of a battery. For example AA alkaline batteries typically have a capacity rating of over 2,500 mAh and AA NiMH batteries have rated capacities of only 1,200 to 1,900 mAh. But when it comes to actually powering an electronic device like a digital camera, the NiMH batteries will often run the device for three or four times as long.
"Heavy Duty" batteries are often the least powerful batteries you can buy.
NiMH and NiCd batteries self discharge at a MUCH faster rate than alkaline batteries. In fact, at "room temperature" (about 70 degrees F) NiMH and NiCD batteries will self discharge a few percent PER DAY. Storing them at lower temperatures will slow their self discharge rate dramatically. NiMH batteries stored at freezing will retain over 90% of their charge for full month. So it might make sense to store them in a freezer. If you do, it's best to bring them back to room temperature before using them. Even if you don't freeze your NiMH batteries after charging them, you should store them in a cool place to minimize their self discharge.
Please add any more info about batteries that you may know as I would like to learn more!
