Stock rechargeable batteries! This has long been dispensed as preparedness advice. The reasoning behind this advice is of course to have the ability to recharge the batteries for additional use once exhausted. If the stores are closed or you can’t get to them for more batteries at least you can rely on stash of rechargeable batteries. Depending on how the long the power is out, they may last you just long enough to get you by with a few modern conveniences like flashlights, headlamps and radios.
At present, there are four main types of rechargeable batteries that are commonly available for use in place of disposable batteries in electronic equipment. There is also larger Lead-Acid batteries (auto and RV) which are also rechargeable but for the purposes of this article I am only covering smaller consumer dry cell batteries. Rechargeable batteries are not all equal, each has it’s own positives and negatives, so which kind should you get? Keep reading and I will break down the different types of batteries for you below!
Non-Technical Battery Lingo for Normal People:
Voltage: Strength of power output of the battery. 1.5 volts is what disposable batteries commonly put out, so rechargeable batteries put out a little less, but are still within the range of what consumer battery appliances need.
mAh: Milliamps Hour (mAh) is important because it’s the easiest way to distinguish the capacity of a battery. The higher the mAh, the more power the battery stores and the longer it will last before needing to be recharged. The higher the number is usually better. Think of a car’s gas tank. Voltage is how much gas is being used, and mAh is the size of the gas tank (source).
LSD: Low Self Discharge; they won’t lose much energy while sitting around unused. Which means long shelf-life.
Charging Cycles: When a battery is completely drained and then completely charged up to full, or when a battery is partial drained and charged up to full that is one changing cycle. Batteries that can hold up to many changing cycles are usually preferred.
Article Source: http://americanpreppersnetwork.com/2014/01/know-batteries.html