A battery is a device that produces electricity by chemical action. A battery contains one or more units called cells. Each cell can produce current.
There are three main types of dry cell batteries: carbon-zinc, alkaline and mercury. Here we are describing an alkaline battery.
An alkaline dry cell battery is more powerful than carbon-zinc battery. It lasts five to eight times longer than a carbon-zinc battery. It has carbon and zinc as electrodes. Instead of a carbon rod extending from the top, a nail like collector (1) is inserted from the bottom. The granules of zinc which form the anode (2) are made uniform in size and shape. The electrolyte – a solution of potassium hydroxide – is in direct contact with the anode, ensuring that the anode is exhausted by the end of the battery’s life. The manganese dioxide cathode (3) is made by electrolysis. The additional oxygen increases the reactivity of the cell. Alkaline dry cells are used mainly for portable radios.
