Реферат: The Chemistry Of Batteries Essay Research Paper

that cannot be reconstituted into their original form after the energy has been

used are called primary cells or voltaic cells. Batteries that contain

chemicals which can be reconstituted when an electric current is passed

through them in an opposite direction of normal cell operation are called

rechargeable cells, storage cells, secondary cells, or accumulators.

Primary cells or dry cell batteries are the most common type of battery

used today. Primary cells were invented by the French chemist Georges

Leclanche in the late 1860 s. During that period this invention was very

important and helped the start of the industrial revolution. It is commonly

know as a dry cell or flashlight battery. The Leclanche cell is very similar to

the dry cell that is used today. The electrolyte is made of zinc, on the

outside shell of the cell, the positive electrode is made of carbon and is

surrounded by a mixture of carbon and manganese dioxide. zinc-carbon

chemistry is used in all AA, C and D dry cell batteries. When the cell is in

use, atoms of the zinc in the outer cases are oxidized, giving up electrons and

forming zinc ions.

Another type of primary cell is a mercury cell. This cell uses zinc as

the negative electrode, mercuric oxide as the positive electrode and an

electrolyte made of a solution of potassium hydroxide. This cell can be

made in the shape of a very small flat disk and is used in electric

wristwatches, hearing aids, and photoelectric cells.

The lead acid cell, also called commercial secondary or storage cell

was invented in 1859 by French physicist Gaston Plante. As mentioned

before, this cell can be recharged by reversing the chemical reaction.

Plante s original cell was a lead acid battery, which is still widely used

today. Just as with Leclanches s cell, it has been vastly improved on over

time. It consists of a lead negative electrode, a sulfuric acid electrolyte, a

porous polymer or glass separator and a lead dioxide positive electrode. As

the cell is used, lead sulfate forms at both electrodes and the sulfuric acid is