21700 Battery Guide: What You Need To Know

21700 Battery Guide: What You Need To Know

21700 Battery Guide

Batteries aren't all the same. One battery might fit one device, but not another, and some batteries are longer-lasting, more powerful, or more reusable than others. 21700 batteries—which are considered a substantial upgrade from the usual 18650 battery—come with unique features and, more importantly, pack a punch. Interested in learning more about 21700 batteries? Here's our 21700-battery guide: what you need to know.

What Is a 21700 Battery?

21700 batteries are rechargeable, lithium-ion cells. They're used to power flashlights, cars, electric bikes, and other heavy-duty devices. The 21700 battery is named after its dimensions: 21mm in diameter and 70mm in length. This way, people can quickly identify their size and compatibility. Batteries can come protected or unprotected. Most protected batteries include PCB and overheat protection. Since unprotected batteries lack these preventative qualities, they're more dangerous and more likely to experience premature malfunctioning or failure. 21700 batteries can vary in build and mAhs. 21700 cells will come in either a flat top version or button top versions. They also have different ranges of mAhs — some lower and some higher.

What's the Difference Between a 21700 Battery and a 18650 Battery?

The 18650 battery was the original gold standard for flashlight batteries. Has the 21700-battery changed that? The main difference between 21700 batteries and 18650 batteries is their size. By increasing the overall length and diameter of the battery, a 21700 cell can reach a maximum capacity of 5000 mAh, compared to the 18650's 3600 mAh. For nitecore flashlight users, this translates to longer runtimes on a single charge.

Should I Upgrade My Batteries?

Now that you’ve gone through our 21700-battery guide: what you need to know, you’re probably wondering if you should upgrade your batteries. 21700 batteries are certainly an upgrade—there's no doubt about it. But if you're planning to use a 21700 battery for your devices, there are a few things you should keep in mind. For instance, most batteries are similar in size, but that doesn't mean they work the same. Some might vary in voltage, charging current, and PTC protection. If your electronic device only accepts 21700 cells that have a guaranteed maximum current or voltage, going over could harm the device. To avoid any issues, make sure you get the proper type of battery for your device.

Search and Recovery Engineering carries effective, high-quality safety equipment, including ropes, shackles, and flashlights. If you're in search of the perfect battery for your flashlight, come check out our selection of rechargeable Nitecore batteries.

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