Dry cell

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Line art drawing of a dry cell:
1. brass cap, 2. plastic seal, 3. expansion space, 4. porous cardboard, 5. zinc can, 6. carbon rod, 7. chemical mixture.

A Dry cell is a type of chemical cells, commonly used today, in the form of batteries, for many electrical appliances. It was developed in 1887 by Yai Sakizō (屋井 先蔵) of Japan and patented in 1892.[1]

A dry cell uses a paste electrolyte, with only enough moisture to allow current to flow. Unlike a wet cell, a dry cell can operate in any orientation without spilling, as it contains no free liquid, making it suitable for portable equipment. By comparison, the first wet cells were typically fragile glass containers with lead rods hanging from the open top and needed careful handling to avoid spillage. Lead-acid battery did not achieve the safety and portability of the dry cell until the development of the gel battery.

A common dry cell is the zinc–carbon battery, sometimes called the dry Leclanché cell, with a nominal voltage of 1.5 volts, the same as the alkaline battery (since both use the same zincmanganese dioxide combination).

A standard dry cell comprises a zinc anode, usually in the form of a cylindrical pot, with a carbon cathode in the form of a central rod. The electrolyte is ammonium chloride in the form of a paste next to the zinc anode. The remaining space between the electrolyte and carbon cathode is taken up by a second paste consisting of ammonium chloride and manganese dioxide, the latter acting as a depolariser. In some designs, the ammonium chloride is replaced by zinc chloride.

Types of dry cells[edit]

Primary cells are not rechargeable. They have to be thrown away after their chemicals are used up.

Secondary cells are rechargeable. They can be used again.

See also[edit]

References[edit]

  1. ^ "1) The Yai dry-battery". The history of the battery. Battery association of Japan. Retrieved 2014-03-19.