Lithium - Ion Round Cell 21700

Lithium-ion batteries have a high energy density and therefore 1.5 to 2 times the capacity of NiMH batteries of the same weight and very low self-discharge. As a result, they have a long shelf life and high storage capacity.

The rigidity and robustness of the round cells due to their housing made of - usually - nickel-plated steel ensures a high degree of stability and insensitivity.
The 21700 cell was introduced to the market as a consistent further development of the cylindrical 18650 cell. It achieves a capacity gain of up to 30% with a diameter of 21 mm instead of 18 mm and a length of 70 mm instead of 65 mm. The better size ratio to the active material usually results in a higher gravimetric energy density.

With a typical capacity of 5,000mAh the number of cells required can be reduced compared to the 18650 round cell. This also reduces the number of contact and welding points required. This means better stability and reliability of the entire pack as well as lower manufacturing costs.

This is why 21700 batteries are increasingly being used not only in vehicles, but also in chargers, e-cigarettes, flashlights, electric bicycles and other devices.

NOTICE: Effects of vibrations on cylindrical lithium ions or primary cell batteries

DATA SHEET 21700