Reusable Energy and Power Sources: Rechargeable Batteries.

Introduction [Rechargeable batteries] will not only reduce the destruction of our environment but also decrease dependence on foreign-controlled oil and increase national security. Energy is a key ingredient in societal and economic development. It is needed to power business and industry (i.e., trucks, machinery, planes, computers, etc.) and to provide those luxuries that assist us in our daily lives (i.e., cell phones, electronic games, automobiles, etc.). The major source of energy is the sun. Through biological conversions, the sun's energy can be transformed into resources such as wood, coal, natural gas, and petroleum. These natural resources are vital to continued economic and technical development. They can be used to drive the machinery that increases productivity of goods and services to meet the needs of our growing populations. Fossil fuels are the major form of energy used to drive our economies, and there has been little variance in their use during the past 50 years. The problem is that more and more people need more and more goods and services. ]he supplies of fossil fuels are limited. As the populations and economies of China, India, and the U.S. continue to grow, so must the energy resources increase. As energy supply fluctuations are punctuated by natural disasters and war, populations experience supply chain disruptions and short-term variations in costs of gasoline, natural gas, propane, and electricity. Humans have modified the world for improved living conditions but have yet to develop many new energy resources, excluding hydroelectric power, nuclear power, and batteries. With our increased reliance on batteries to power many of our industrial and consumer goods, what does the future hold for battery technologies? Rechargeable batteries are very popular within consumer electronics. If one uses a cell phone or portable electric tool, she/he understands the need to have a reliable product and the need to remember to use the recharging systems that follow a cycle of charge/discharge. This article reviews the types of rechargeable batteries that are available, including their composition and charging and discharging capabilities. Batteries are energy storage devices. In them, chemicals are put together. The chemical molecules react and produce voltage differences between positive and negative electrodes. These differences produce current flow in the energy forms to power products. The chemical flowing agent is referred to as the electrolyte. Figure 1 on the previous page shows a typical sealed lead-acid battery that may be used in a variety of high-current-demand applications. [FIGURE 1 OMITTED] The power demand and chemical compositions determine the life of a battery. It also depends on whether the batteries are deemed useless after they are discharged or if the reverse flow of electricity through the chemicals can extend their usefulness (recharge). Some newer batteries have to be cycled (charged/discharged) several times to build their capacity. It needs to be noted that there is no such thing as 100 percent reusable energy in a rechargeable battery. No matter how we invent or classify the renewable energy, there are always losses, losses in material or gases generated. Lead-Acid Battery The lead-acid battery is a well-known device used in various equipment, such as cars, construction equipment, and heavy duty electrical backup systems. This type of battery is very heavy because of its lead-cell construction. Lead-acid batteries usually are manufactured as a six-cell integrated battery that produces a maximum output of 12 volts. The lead-acid battery has a positive plate, the lead-acid storage cell, which is made of lead peroxide, Pb[O.sub.2]. There is also a negative plate of pure sponge lead, Pb, per cell. Diluted sulfuric acid, [H.sub.2]S[O.sub.4], is used as the electrolyte to allow the electrons to flow back and forth to produce the electrical charge. …