Batteries And Their Importance Essay Research Paper

Batteries and Their Importance- We use batteries everyday, we use them to start our cars and to listen to our Walkmans. I have a few questions: How do batteries work? What are the different kinds of batteries? Why do they die? Why do they lose energy when they are not used for a long time? Well I tried my best to find the best answers for these questions and a little more. Battery, also called an electric cell, is a device that converts chemical energy into electricity. All batteries contain an electrolyte, a positive electrode, and a negative electrode. There are two general types of batteries. Batteries in which chemicals cannot be reconstituted into their original form once their energy have been converted these are called primary cells. Batteries in which the chemicals can be reconstituted by passing an electric current through them in the opposite direction are known as secondary cells, are rechargeable cells. The primary battery is the most common type of battery used today, invented by the French chemist Geoges Leclanche in the late 1860 s. At the time this invention was very important and helped the start of the industrial revolution. It allowed people with portable electricity. This popular invention was called the dry cell or flashlight battery. The Lechlanche cell is very similar to the dry cell we use today. The positive pole is a rode of carbon embedded in a black manganese dioxide (MnO2) and Carbon particles and the negative electrode is made of zinc. The electrolyte consists of a mixture of ammonium chloride and zinc chloride made into a paste. This sits in between the negative and positive electrodes, which acts as an ionic conductor. When the cell is in use, atoms of the Zinc in the outer case are oxidized, giving up electrons and forming zinc ions. Zn – 2e Zn++ The electrons are lost by the zinc atoms then flow through the load (the device being powered) and supply energy. They re-enter the cell at the carbon rode that serves as the positive electrode. As this series of events happen, the battery begins to lose pure zinc atoms, and the battery starts to die. This type of cell gives about 1.5 volts of energy. By connecting many cells in a series a rather high voltage can be produced. Another type of primary cell is the mercury cell. This cell uses zinc as the negative electrode, mercury as the positive electrode, and potassium hydroxide as the electrolyte. This cell gives about 1.3 volts of electricity, and is used in hearing aids and watches because the battery can be flattened. Primary cells maintain a positive charge on the positive terminal and a negative charge on the negative terminal, month after month. These charges attract another and sometimes manage to get to each other through the battery it self. When this happens the battery loses some energy. This is why batteries lose energy if not used. It is possible to slow this process down by refrigerating batteries. Dry Cell Battery The storage, or secondary cell, which can be recharged by reversing the chemical reaction, was invented in 1859 by the French physicist Gaston Plante. This invention was very crucial because it would revolutionize cars. Instead of crank starts the lead-acid battery was used. The lead-acid, which Plante invented is still the same basic design today. The battery consists of six cells connected in a series, and is used in automobiles. Its chief advantage is that it can deliver a strong current of electricity (starting an engine), however it runs down quickly. Each cell is made up of a number of positive and negative plates, separated by thin layers of wood, hard rubber, or plastic, called separators. All the positive plates are connected to one strap, and all the negative plates are also connected to one strap. The straps are connected to terminal posts, positive and negative. Each of the plates are in the form of grids containing pockets. The positive plates pockets are filled with a paste of lead dioxide (PbO2). The negative plates are filled with spongy lead (Pb). Both plates are immersed in a solution of sulfuric acid, this acts as the electrolyte. When the battery is in use, the lead atoms in the negative plates lose electrons and become lead ions (Pb++). These ions combine with the electrolyte to form a white coating of lead sulfate on the negative plate. Pb++ + SO4- PbSO4 When the electrons make through the load and arrive on the positive pole they form a white coating of lead sulfate on the positive plate also. The coat of lead sulfate makes the battery less efficient. When an outside current is applied the reaction happens backwards, changing the lead sulfate coating on each plate to lead and lead dioxide. After this the battery is recharged. Lead-acid storage Another widely used secondary cell is the alkaline cell, which was invented by the American, Thomas Edison in the 1900 s. It works similar to the lead-acid battery, but it is much smaller. A disadvantage is that the battery loses a little bit of capacity each time it is charged. In recent years a number of new types of batteries have been designed for use in electric vehicles and other applications. In improving various conventional storage batteries, they have been able to make electric cars and longer lasting batteries. Still there exits some draw backs to these batteries, either short range, high expense, bulkiness, or environmental problems. The U.S Advanced Battery Consortion (USADC) was set up in 1991 to speed up development of new storage batteries. Batteries are being developed that cause no environmental hazards and occupy little space. All this advancement in batteries is wonderful, but we need to see the importance batteries play in the world today. The world is dependent on the battery, from the use in cars to calculators. The battery is one of the few sources of energy that is universal, a Japanese calculator can still work with batteries found in the U.S no electric conversion is needed. This is reason why the battery is so needed and important to the world.