Lithium batteries may be considered a best choice for the most common type of consumer battery (AA-size) (and other sizes!) when used in emergency applications. That is, in a electronic device whereby you need the assurance that it will function at its full potential under harsh conditions and perhaps after having not been used for a very long time.
Here is a list of reasons why lithium batteries are the best:
Lithium batteries are becoming much more common and are now readily available as a replacement for the common alkaline-AA battery. While ‘NiMH’ Rechargeable Batteries are great and definitely have their advantages (they’re rechargeable!) (and for these reasons), there are certain applications and reasons why you might want to consider the lithium battery…
For example, lets say that you keep an emergency flashlight (e.g. the 300 lumen Fenix LD22) (reviewed here) in your vehicle for ’emergencies’. You definitely want to be sure that this flashlight will operate at its full potential if you ever need it. So, which ‘AA’ battery is the best for this? In my opinion, it’s the lithium battery.
Similarly for other important electronic devices that may take ‘AA’ batteries such as an emergency radio, handheld 2-way radios, a weather alert radio, portable GPS, smoke detectors, etc.., a best battery might be the lithium.
Here are the major reasons why lithium batteries may be considered the best:
High Power Density
Lithium batteries have more than three times the energy density of alkaline batteries (4.32 versus 1.3 MJ/L)! In fact the next most energy dense ‘chemical’ is Hydrogen at 5.6 MJ/L, so as you can see, these batteries pack quite a punch…
What does this mean? It means that the lithium battery will last significantly longer than a similarly sized alkaline battery. For example, ‘Energizer®’ claims for their ‘AA’ lithium battery: “World’s longest-lasting AA battery in high-tech devices lasts 6x longer than the other leading brand in digital cameras.”
For some applications this might not be exceedingly important, however for certain emergency or other uses this is most definitely an important consideration.
Low Self Discharge
All batteries will slowly discharge over time. Some faster than others.
Often, a so called ’emergency’ device may not be in use for a long time. But if and when it comes time to use it, you surely want to be sure that it works and the batteries have not discharged and become weak over time…
Cold Weather Performance
A major reason why lithium batteries are best for some applications is due to their resilience in cold weather climates. Other batteries will diminish (some significantly!) when they get cold, but the lithium will hold up very, very well in cold weather.
From the Energizer® website, their ‘AA’ lithium battery “performs in extreme temperatures from -40°F to 140°F “.
For example I use ‘AA’ lithium batteries in my driveway alarm transmitter (winter gets very cold up here in north-country). They have been working great! I also use them in my flashlight for the truck.
Long Shelf Life
Because of the inherent low self-discharge properties, the shelf life of a lithium battery is outstanding. Lithium batteries can ‘sit on the shelf’ for a very long time and still maintain most of their energy. Again from ‘Energizer®’, they claim that they will “hold power for 20 years when not in use.”
Weighs 1/3 less than standard alkaline batteries. This may or not be important to you (depends on application), however it is notable.
Energizer® claims “No leaks Guaranteed” for their Energizer® Ultimate Lithium Batteries. A leaking battery will damage your electronic device, and traditional alkaline batteries tend to leak/corrode at the battery terminals over a long time of non-use.
The price of lithium batteries have come down significantly and I have been incorporating them into my electronic devices where applicable. I still keep a supply of NiMH rechargeable batteries for many things, however the lithium’s are great for other applications as listed above.