The 4 Cell Panasonic Bicycle Light Battery 6800mAh is equipped with 4 of the best 18650 cells available on the market - the Panasonic 3400mAH 18650 li-ion cells. Its performance is unmatched. Effectively it has a capacity that is 155% higher than a standard 4400 mAh Li-ion battery, so will give you at least 55% longer runtime when compared with the same light.