As much as we love a good AA or AAA penlight, in order to get the brightest and most powerful outputs, the flashlight industry relies on li-ion batteries to provide the juice necessary. The downside is that li-ion batteries aren’t as widely available as alkaline and niMH/niCd batteries and if you’ve never used them before, can present a bit of a learning curve.
Today’s blog will help you get acquainted with how to shop for the right li-ion batteries for your device as well as introduce you to your options for charging li-ion batteries. Let’s dive in!
Originally developed for use in laptop battery packs, 18650 li-ion batteries are by far the most frequently used battery types in today’s LED flashlights. Only slightly larger than a traditional AA battery, the 18650 has become the gold standard in the flashlight market for its balance of size, output and charging lifespan.
You might be wondering at why we call these batteries 18650s, and believe it or not, there is rhyme and reason. For all li-ion batteries, the name is composed in the following way:
- First two digits indicate the diameter of the battery in mm
- Second two digits indicate the length of the battery in mm
- The “0” indicates it is a round cell
Based on the above convention, you can see that an 18650 battery is 18 mm in diameter, 65 mm in length and circular in shape. And yes, we do have batteries in all sorts of dimensions! For example, a smaller cell that is quite popular in many everyday carry flashlights is a 16340. Although flashlights using these cells will ultimately be capable of less powerful outputs and have shorter runtimes than their 18650 counterparts, the smaller size is often preferred for everyday use.
Once you’ve determined the correct size battery for your flashlight, there are 2 other specifications you’ll want to pay attention to.
The capacity of the battery is given in milliamp hours or mAh and is usually listed on the side of your battery. For an 18650 battery, typical capacities will range from 2300 to 3500mAh while a smaller 16340 cell will have capacities in the 500-700mAh range. In general, the higher the capacity rating, the longer runtime you will get from your flashlight while lower capacities will be more budget-friendly.
The other specification to be aware of is the max discharge rating. Measured in amps or A, this number indicates the amount of electrical discharge at a given moment.
Perhaps the most important thing you can do to ensure that the batteries you purchase will be compatible with your flashlight is to follow the manufacturer’s recommendations. For instance, most of the time an 18650 battery can be substituted with two 16340 size batteries, but not always. And as mentioned before, some newer flashlights require custom or high drain batteries to reach their full lumen potential.
And if you ever have questions, you can always reach out to our customer service team who will be happy to point you to the correct cell for your flashlight.
Now that you have the right batteries for your flashlight, let’s take a look at your options for charging.
What You Need to Know about Li-ion Batteries & Chargers is written by Chinhua Wang for blog.longhorntactical.com