The Chemistry Of Batteries Essay Research Paper

The Chemistry Of Batteries Essay, Research Paper The Chemistry Of Batteries People use batteries in their everyday life without thinking of their impact. Batteries help us get around, keep in touch, have fun, and tell the time. They do this by powering our cars, cell phones, pagers, portable CD players, watches and many other useful tools. They can even save our lives by powering things like smoke detectors, carbon dioxide detectors and glucose meters. In this term paper I will discuss how batteries function, what types of batteries exist, what gives them their power and many other topics related to batteries. The battery, also known as an electric cell, is a device that converts the energy from chemicals into electricity. Chemical reactions that are able to produce electrons

are called Electro-chemical reactions. A battery basically consists of two or more cells that are connected in a series or parallel. All cells are made of a liquid, paste, or solid electrolyte and a positive electrode, as well as a negative electrode. The electrolyte works as an ionic conductor, this causes one of the electrodes to react. This reaction produces electrons while the other electrode accepts the electrons. Every battery has two terminals, one positive and the other negative. Electrons collect on the negative terminal of the battery. If the negative and positive terminal are connected together, then connected to whatever device that needs to be powered, also called a load, the electrical current will flow freely into the device. The speed of the electron production by

the chemical reaction is called the battery s internal resistance. This controls how many electrons can flow between the two terminals. Because electrons must flow from the battery into a wire, and then must travel from the negative to the positive terminals in order for the chemical reaction to take place. This is why batteries can go unused for a year and still have plenty of power. There are two general types of batteries. Batteries that have chemicals 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,