LED torches & batteries
LED-torches with AAA-batteries, small and compact!
Because of their small size, AAA-batteries are very often used in keychain-torches. You can very easily carry this type of torch with you daily, without them being in the way.
However, do not underestimate a torch with AAA-batteries because of their size. For example, the Fenix E01 can offer 13 lumens for a burn time of 16.5 hrs. These 13 lumens are plenty of light to light up a key hole or find your way in a dark house when the power has gone out.
An important advantage of torches on AAA-batteries is the fact that you can purchase these batteries anywhere. Everybody usually has a few of these batteries lying arround in a kitchen drawer. And if not, you can get them at any supermarket for a very sharp price. Besides, you can always choose between alkaline- or lithium batteries for one time use, or rechargeable NiMH-batteries. These you can use many times, of course.
Rechargeable NiMH-batteries are suitable for use in powerful torches, they are also very competitively priced. You can find many different versions with different capacities. Each version has it's advantages and disadvantages. For example, the batteries with a higher power supply are often more sensitive to self discharge. This means that you have to use and charge them regularly. The rechargeable batteries with a lower power supply are often less sensitive to self discharge. This way, you can leave them unused for a longer time, while the charge does not decrease.
Alkaline batteries are most common. Therefore you will find these in practically every store. Al though they are not rechargeable, a big advantage is the fact that they can be bought at quite good prices usually. Also, they keep their charge for approximately 4 years. However, the alkaline batteries are not so suitable for torches that require a higher power supply. Also, they have a risk of battery leakage, if not regularly used.
The more expensive lithium batteries supply a higher amperage than the alkaline version. LED-torches which are designed for use with alkaline-batteries, often function fine with lithium-batteries as well. However, for torches that work with a light bulb, you still have to watch out. The higher amperage can blow out some of these bulbs. However, this is dependent of the specifications of the lithium-batteries which you use. It's important to keep this in mind. On the other hand, there is no risk in using alkaline batteries in torches that are designed for lithium batteries.