Camelion - Button Cells
Button cell batteries also known as watch batteries are small single cell batteries typically 5 to 25 mm diameter and 1-6 mm high. The positive terminal of the battery is the bottom part of the battery while the negative part is the insulated top. They are used for: watches, pocket calculators, artificial cardiac pacemakers, car keys and hearing aids. A couple of widely used button cell batteries are CR2032, CR2016, CR2325 and many others.