Quick Answer
The best 21700 Rechargeable Li-ion batteries are:
- LCLEBM Flat Top 21700 Battery — 3.6V — 5500mAh — $26 for two
- TQTHL 21700 Rechargeable Battery — 3.6V — 5500mah — $27.80 for two
- IMREN 27000 Rechargeable Battery — 3.7V — 4500mAh — longer than normal 21700 — recharges via USB-C — $21 for one
The Details on 21700 Batteries
21700 batteries are a similar size to 18650 batteries but are a little bit wider and longer. 21700 batteries are usually 3.6 or 3.7 volts.
Like other lithium-ion battåeries, 21700 batteries have a high energy density, meaning they can store a lot of energy in a relatively small size. They typically have a nominal voltage of 3.6-3.7 volts and a capacity ranging from around 3000 mAh to over 5000 mAh, depending on the specific model.
21700 rechargeable lithium-ion batteries are a type of cylindrical battery similar in shape to other popular lithium-ion battery sizes such as 18650 and 26650 batteries. Still, they have a larger diameter of approximately 21 mm and a length of around 70 mm.
21700 batteries are becoming increasingly popular in applications that require high-capacity, high-performance batteries, such as electric vehicles, power tools, and high-drain flashlights. They can also be used in other electronic devices that require a lot of power, including laptops, e-bikes, and solar generators.
Compared to other popular lithium-ion battery sizes, 21700 batteries are relatively new and offer some advantages in terms of performance and size. They can often deliver higher power output and better thermal management than smaller batteries while also providing more energy storage than larger batteries. However, they may not be compatible with devices designed for other battery sizes, so it’s important to check the manufacturer’s specifications before using them.
