In the world of flashlights, there are many different battery types being used. You have probably heard flashlight fanatics throw around crazy terms like CR123A, 26650, 18650, or D-Cell. What the heck does all this babble mean? Don't worry, we'll explain.
First, it's important to note that the two major battery types most often used are Alkaline batteries and Lithium batteries. Both have their fair share of advantages and disadvantages.
ALKALINE - We are all familiar with Alkaline batteries. These are your traditional AA, AAA, 9-Volt, C Cell, and D Cell batteries. These are the same batteries used in remote controls, smoke alarms, and a myriad of other low voltage electronics. Alkaline batteries are great - they are cheap, durable, and safe. You can find Alkaline batteries being used in almost every entry level flashlight and even in some mid-range flashlights. However, due to the low voltage of alkaline batteries (1.2v - 1.5v), they are not too useful for powering high output flashlights.
To put it in perspective, a standard AAA battery only has a voltage of 1.2v whereas a standard Lithium-Ion battery has a voltage of 3.7v. Now, it is possible to run alkaline batteries linearly to achieve a greater voltage; however, this quickly becomes inefficient when you begin to approach more powerful flashlights. Have you guys seen how big those store brand 1000 lumen flashlights are? They need to be that big in order to accommodate all the alkaline batteries.
LITHIUM - The other battery type is known as Lithium. In this particular example, we'll be reviewing both Lithium-Ion and Lithium batteries. These batteries are considered to be the grand daddy of power sources in the flashlight world. They are small, efficient, and can power all of your favorite flashlights. However, there is an important distinction between the two battery types.
Non-Rechargeable: The Non-Rechargeable Lithium batteries include a model of battery called CR123A. These are 3V Lithium batteries available for purchase at almost any convenience store and are used exclusively by some brands like Streamlight. They are also found in some digital cameras (and are sometimes referred to as camera batteries). These are great little batteries and can definitely provide the necessary power for some higher end flashlights. However, they can not be recharged and need to be disposed of once drained. They retail for approximately $3-$7 each (depending where you buy them) and have a voltage of 3v. While this still isn't as good as the 3.7v found in rechargeable Lithium-Ions, it's light years ahead of the 1.2v-1.5v found in alkaline batteries. The picture below shows two CR123A Lithium batteries used in our TakLite Elite LED Flashlight.
Rechargeable: The other variation of Lithium batteries are Lithium-Ion - also known as the rechargeable kind. These include models like 14500, 16340, 18650, 26650, and so on. These numbers essentially refer to the size of the battery. In the context of flashlights, size 18650 seems to be the most popular and also the one we use in our TakLite flashlights. These batteries are great because they can be recharged and will last the user well over two years before they need replacing. From a price perspective, a single 18650 battery can cost approximately $10 whereas a single non-rechargeable CR123A battery can cost anywhere from $3-$7. It simply makes more sense to use the rechargeable kind. In the picture below, you can see our own TakLite 18650 Lithium-Ion battery being used with the TakLite Elite LED Flashlight.
Fun Fact: Did you know - these are the exact same batteries used in laptop battery packs and electric cars? Just take a look at the picture below. Look familiar?