Learn More About Lithium-Ion Batteries

Lithium-ion batteries exist everywhere from cell phones to electric cars and more. If you're a tactical flashlight user, you're probably quite familiar with lithium-ion batteries. Many LED flashlights are compatible with lithium-ion batteries for various reasons. First of all, lithium-ion batteries are extremely powerful, providing a lot of energy to the product being used. They are also rechargeable, making them extremely convenient and often more cost effective. So in this blog today, we'll be talking about lithium-ion batteries and answering a few questions that we've received regarding lithium-ion batteries. We’ll mostly be focusing on lithium-ion batteries that are used in flashlights for this blog.

Lithium-Ion Batteries Can Range in Size

Lithium-ion batteries come in various sizes from 10440 batteries that are so small and fit into many keychain flashlights to 26650 batteries that are quite long and quite wide. Many pocket lights take 16340 lithium-ion batteries or 14500 lithium-ion batteries. Bigger EDC lights usually take 18650 batteries or 21700 batteries. And bigger handheld lights will often take 26650 batteries. Of course, this isn't a hard and fast rule. A larger light may take two 18650 batteries or even four 18650 batteries.

With any tactical flashlight, it's important to check what battery it takes. We sometimes receive questions asking us if a 26650 battery will fit in an 18650 flashlight. Since all of these batteries range in size, It's important to check the manual to see what batteries fit in your flashlight. For example, the Klarus XT11X is able to run on one 18650 battery, two CR123A batteries, and two Klarus 16340 batteries. Many flashlights even come with battery carriers to accommodate different lithium-ion battery sizes. So make sure you know what your flashlight is able to run on.

What Does the mAh Stand For?

MAh stands for milliamps per hour and is a form of measurement for electric power. Many lithium-ion batteries will have a mAh number on the plastic covering of the battery. The higher the mAh, the longer the run time will be. You'll see a variety of 18650 batteries like this. So you can have an 18650 battery that has a 2600 mAh and an 18650 battery that has 3500 mAh. That 3500 milliamp battery is going to be giving you fairly significantly longer run times with your flashlight.

When you purchase a tactical flashlight, it may come with an 18650 battery with a 2600 mAh capacity. You may want to upgrade your battery to a 3500 mAh battery. No worries, this is completely safe! So long as you're using the same battery type and are using a protected battery, a higher rated milliamp battery will not harm your flashlight.

What is the Difference Between a Protected Battery and an Unprotected Battery?

When shopping for lithium-ion batteries, you may notice that you can find protected cells and unprotected cells. Let's start by discussing what a protected cell is. A protected battery features an electronic circuit that is designed to protect the battery from various dangers. A protected battery will typically feature an overheating protection, overcharge protection, over discharge protection, and overcurrent protection. With some batteries, you may find more protections in place, but the ones listed above are pretty common for most protected batteries.

As for unprotected batteries, to put it simply, they don't have these protections in place and don't feature the electronic circuit that is designed for those protections. These batteries are more likely to overcharge, overheat, over discharge, and short circuit. We always recommend to use protected batteries because they are more reliable and safer to use.

How to Maintain Lithium-Ion Batteries

Lithium-ion batteries are quite different from your typical AA alkaline batteries that you often find in common electronics. Unlike Alkaline batteries, you can't just leave lithium-ion batteries in a drawer until you need them. Lithium-ion batteries drain slowly over time even when they're not in use. For that reason, they require a charge every once in a while to make sure that they are still good to use and ready to go. We recommend charging lithium-ion batteries every month or every other month.

Another way to keep your battery healthy is to make sure you do not drain it completely in the flashlight. With many non-rechargeable batteries, it makes sense to drain the battery completely so that you get your money's worth. However, lithium-ion batteries are rechargeable and it's always best to charge them before draining them completely. By completely draining the energy out of the battery, you lessen that battery’s life.

Likewise, if you use most of the battery’s energy and leave it alone without charging it, that lithium-ion battery is going to drain slowly. This can be quite a problem because you may have issues reviving that battery from being completely dead. You also don’t want to leave the lithium-ion battery on the charger constantly. There’s a good balance between using the battery and charging it which honestly sounds more complicated than it is.

Storing Your Lithium-Ion Battery

Next, let's talk about storing your lithium-ion batteries. First and foremost, it's important to know that the positive ends of the batteries and the negative ends of the battery should line up. You want to make sure that you don't accidentally store your lithium-ion batteries where the negative and positive ends are connecting at all as this can be dangerous. You can always choose to separate the batteries with a bit of plastic and then you wouldn't have to worry about it.

We also recommend storing batteries in a location at room temperature. Lithium-ion batteries drain more quickly in the cold so your car or the garage is probably not the best place for them. Keeping them in a drawer in the house is probably best for the health of the batteries. If you keep up with the maintenance of your lithium-ion batteries, they can be your best friends. They last an extremely long time and you can truly get your money's worth and more out of them.

Check out our battery selection to see if any of our lithium-ion batteries work for you. If you have any other questions about lithium-ion batteries, contact us and let us know! We would be happy to answer them.