Most of the 18650 batteries on the market have a capacity of 2,200 mah, which means it has a voltage of 3.7V and a current of 2200mA. But that's not the only one, there's another one that's 2400 mah and 2600 mah. And most of the laptops we know of that have a long life are powered by these high-capacity specs, like a 2,600mah battery. The 18650 battery comes in three sizes, divided into three cells, four cells and six cells according to its composition.
