Alkaline batteries are a type of power cell dependent upon the reaction between zinc and manganese dioxide (Zn/Mn0₂). Compared with traditional carbon/zinc batteries , whilst both produce approximately 1.5 volts per cell, alkaline batteries have a higher energy density and longer shelf-life. Compared with silver-oxide batteries , which alkalines commonly compete against in button cells, they have lower energy density and shorter lifetimes.

A cell consists of a steel can, nickel-plated at both ends, the negative, flat terminal being electrically isolated with a nylon seal. Inside the can is the manganese dioxide cathode, a separator membrane, the powdered zinc anode in a potassium hydroxide water electrolyte. Finally, at the axis is a brass pin electrically connected to the negative terminal.

The long-lasting alkaline battery was invented in 1959 by Eveready Battery engineer Lewis Urry.