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Electric battery

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❶It is defined as the current through the battery divided by the theoretical current draw under which the battery would deliver its nominal rated capacity in one hour. This resistance experienced by an electron or current inside the cell or battery is called the internal resistance of the cell or battery.

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His cell consisted of a zinc and a copper electrode immersed in an electrolytic solution of salt and water. He also popularized the electrophorus, a machine that could produce large quantities of static charge.

He did not, however, invent it, though he is often credited with doing so. Volta was made a count by Napoleon Bonaparte in , and one of the SI units of electricity, the volt, was named after him in Because it is a difference in electric potential rather than an amount of electric current, high voltage is not necessarily dangerous, while high current can be.

When discussing electricity, the analogy of a water hose is often used. In this analogy, voltage is likened to water pressure difference--a high pressure difference will result in a faster electron flow.

Current, measured in amps, describes how fast a given volume of electrons travel past a certain point in the circuit. Most batteries available on the market may have high voltages, but the amperage available depends on the circuit the battery is used in, not on the battery itself. As battery technology has advanced, devices running on battery power have become smaller and more powerful.

The widespread use of lithium-ion Li-ion batteries, for example, has allowed cell phones to become exponentially smaller than their forebears, mainly due to their low power-to-weight ratio. In these batteries, a lithium ion moves one way between the anode and cathode during discharge, and the other way during recharging.

The Toyota Prius, a popular hybrid automobile, debuted on the market using nickel-metal hydride Ni-MH batteries. Its next generation of batteries, available in late , will also be lithium-ion due to their advantages over the Ni-MH battery pack.

Batteries range in voltage from a few hundredths of a volt to many hundreds of volts, depending on both the size of the battery and the materials from which it is made.

They are an excellent way to power various forms of devices, no matter what the voltage requirements of those devices. Wolfram Donat is an information technology professional and writer currently finishing a degree in computer systems engineering. The VRLA battery uses an immobilized sulfuric acid electrolyte, reducing the chance of leakage and extending shelf life.

The two types are:. Other portable rechargeable batteries include several sealed "dry cell" types, that are useful in applications such as mobile phones and laptop computers. Cells of this type in order of increasing power density and cost include nickel—cadmium NiCd , nickel—zinc NiZn , nickel metal hydride NiMH , and lithium-ion Li-ion cells. Li-ion has by far the highest share of the dry cell rechargeable market. NiMH has replaced NiCd in most applications due to its higher capacity, but NiCd remains in use in power tools , two-way radios , and medical equipment.

In the s, developments include batteries with embedded electronics such as USBCELL , which allows charging an AA battery through a USB connector, [28] nanoball batteries that allow for a discharge rate about x greater than current batteries, and smart battery packs with state-of-charge monitors and battery protection circuits that prevent damage on over-discharge.

Low self-discharge LSD allows secondary cells to be charged prior to shipping. Many types of electrochemical cells have been produced, with varying chemical processes and designs, including galvanic cells , electrolytic cells , fuel cells , flow cells and voltaic piles. A wet cell battery has a liquid electrolyte. Other names are flooded cell , since the liquid covers all internal parts, or vented cell , since gases produced during operation can escape to the air.

Wet cells were a precursor to dry cells and are commonly used as a learning tool for electrochemistry. They can be built with common laboratory supplies, such as beakers , for demonstrations of how electrochemical cells work.

A particular type of wet cell known as a concentration cell is important in understanding corrosion. Wet cells may be primary cells non-rechargeable or secondary cells rechargeable. Originally, all practical primary batteries such as the Daniell cell were built as open-top glass jar wet cells. Other primary wet cells are the Leclanche cell , Grove cell , Bunsen cell , Chromic acid cell , Clark cell , and Weston cell. The Leclanche cell chemistry was adapted to the first dry cells.

Wet cells are still used in automobile batteries and in industry for standby power for switchgear , telecommunication or large uninterruptible power supplies , but in many places batteries with gel cells have been used instead. These applications commonly use lead—acid or nickel—cadmium cells. 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 batteries did not achieve the safety and portability of the dry cell until the development of the gel battery. 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. Molten salt batteries are primary or secondary batteries that use a molten salt as electrolyte.

They operate at high temperatures and must be well insulated to retain heat. A reserve battery can be stored unassembled unactivated and supplying no power for a long period perhaps years. When the battery is needed, then it is assembled e. For example, a battery for an electronic artillery fuze might be activated by the impact of firing a gun. The acceleration breaks a capsule of electrolyte that activates the battery and powers the fuze's circuits.

Reserve batteries are usually designed for a short service life seconds or minutes after long storage years. A water-activated battery for oceanographic instruments or military applications becomes activated on immersion in water. A battery's characteristics may vary over load cycle, over charge cycle , and over lifetime due to many factors including internal chemistry, current drain, and temperature. At low temperatures, a battery cannot deliver as much power. As such, in cold climates, some car owners install battery warmers, which are small electric heating pads that keep the car battery warm.

A battery's capacity is the amount of electric charge it can deliver at the rated voltage. The more electrode material contained in the cell the greater its capacity.

A small cell has less capacity than a larger cell with the same chemistry, although they develop the same open-circuit voltage. The fraction of the stored charge that a battery can deliver depends on multiple factors, including battery chemistry, the rate at which the charge is delivered current , the required terminal voltage, the storage period, ambient temperature and other factors.

The higher the discharge rate, the lower the capacity. Batteries that are stored for a long period or that are discharged at a small fraction of the capacity lose capacity due to the presence of generally irreversible side reactions that consume charge carriers without producing current.

This phenomenon is known as internal self-discharge. Further, when batteries are recharged, additional side reactions can occur, reducing capacity for subsequent discharges. After enough recharges, in essence all capacity is lost and the battery stops producing power. Internal energy losses and limitations on the rate that ions pass through the electrolyte cause battery efficiency to vary.

Above a minimum threshold, discharging at a low rate delivers more of the battery's capacity than at a higher rate. High-drain loads such as digital cameras can reduce total capacity, as happens with alkaline batteries. The C-rate is a measure of the rate at which a battery is being charged or discharged. It is defined as the current through the battery divided by the theoretical current draw under which the battery would deliver its nominal rated capacity in one hour. A 2C discharge rate means it will discharge twice as fast 30 minutes.

A 1C discharge rate on a 1. A 2C rate would mean a discharge current of 3. Standards for rechargeable batteries generally rate the capacity over a 4-hour, 8 hour or longer discharge time. Because of internal resistance loss and the chemical processes inside the cells, a battery rarely delivers nameplate rated capacity in only one hour. Types intended for special purposes, such as in a computer uninterruptible power supply , may be rated by manufacturers for discharge periods much less than one hour.

The C-rate presents a dimensional error: C is in ampere-hours and not amperes, and one can not express a current in ampere-hours. For this reason the concept I t was introduced by the international standard IEC [33] , I t being equal to the capacity C divided by one hour, hence allowing a mathematically correct method of current designation. The figures used for expressing the discharge rate remain the same: As of [update] , the world's largest battery was built in South Australia by Tesla.

It can store MWh. It was manufactured by ABB to provide backup power in the event of a blackout. The battery can provide 40 MW of power for up to seven minutes. Lithium—sulfur batteries were used on the longest and highest solar-powered flight.

Battery life and its synonym battery lifetime has two meanings for rechargeable batteries but only one for non-chargeables. For a non-rechargeable these two lives are equal since the cells last for only one cycle by definition. The term shelf life is used to describe how long a battery will retain its performance between manufacture and use. Available capacity of all batteries drops with decreasing temperature.

In contrast to most of today's batteries, the Zamboni pile , invented in , offers a very long service life without refurbishment or recharge, although it supplies current only in the nanoamp range. The Oxford Electric Bell has been ringing almost continuously since on its original pair of batteries, thought to be Zamboni piles.

The rate of side reactions is reduced for batteries stored at lower temperatures, although some can be damaged by freezing. However, newer low self-discharge nickel metal hydride NiMH batteries and modern lithium designs display a lower self-discharge rate but still higher than for primary batteries. Internal parts may corrode and fail, or the active materials may be slowly converted to inactive forms.

The active material on the battery plates changes chemical composition on each charge and discharge cycle; active material may be lost due to physical changes of volume, further limiting the number of times the battery can be recharged.

Most nickel-based batteries are partially discharged when purchased, and must be charged before first use. Some deterioration occurs on each charge—discharge cycle.

Degradation usually occurs because electrolyte migrates away from the electrodes or because active material detaches from the electrodes. Fast charging increases component changes, shortening battery lifespan. If a charger cannot detect when the battery is fully charged then overcharging is likely, damaging it. NiCd cells, if used in a particular repetitive manner, may show a decrease in capacity called " memory effect ". NiMH cells, although similar in chemistry, suffer less from memory effect.

Automotive lead—acid rechargeable batteries must endure stress due to vibration, shock, and temperature range. Because of these stresses and sulfation of their lead plates, few automotive batteries last beyond six years of regular use. Starting, Lighting, Ignition batteries have many thin plates to maximize current. In general, the thicker the plates the longer the life.

They are typically discharged only slightly before recharge. Deep-cycle lead—acid systems often use a low-charge warning light or a low-charge power cut-off switch to prevent the type of damage that will shorten the battery's life. Battery life can be extended by storing the batteries at a low temperature, as in a refrigerator or freezer , which slows the side reactions.

Primary batteries readily available to consumers range from tiny button cells used for electric watches, to the No. Secondary cells are made in very large sizes; very large batteries can power a submarine or stabilize an electrical grid and help level out peak loads.

A battery explosion is generally caused by misuse or malfunction, such as attempting to recharge a primary non-rechargeable battery, or a short circuit. When a battery is recharged at an excessive rate, an explosive gas mixture of hydrogen and oxygen may be produced faster than it can escape from within the battery e. In extreme cases, battery chemicals may spray violently from the casing and cause injury.

Overcharging - that is, attempting to charge a battery beyond its electrical capacity - can also lead to a battery explosion, in addition to leakage or irreversible damage.

It may also cause damage to the charger or device in which the overcharged battery is later used. Car batteries are most likely to explode when a short-circuit generates very large currents.

Such batteries produce hydrogen , which is very explosive, when they are overcharged because of electrolysis of the water in the electrolyte. During normal use, the amount of overcharging is usually very small and generates little hydrogen, which dissipates quickly. However, when "jump starting" a car, the high current can cause the rapid release of large volumes of hydrogen, which can be ignited explosively by a nearby spark, e. Disposing of a battery via incineration may cause an explosion as steam builds up within the sealed case.

Recalls of devices using Lithium-ion batteries have become more common in recent years. This is in response to reported accidents and failures, occasionally ignition or explosion. If a battery cell is charged too quickly, it can cause a short circuit, leading to explosions and fires".

Many battery chemicals are corrosive, poisonous or both. If leakage occurs, either spontaneously or through accident, the chemicals released may be dangerous. For example, disposable batteries often use a zinc "can" both as a reactant and as the container to hold the other reagents. If this kind of battery is over-discharged, the reagents can emerge through the cardboard and plastic that form the remainder of the container. The active chemical leakage can then damage or disable the equipment that the batteries power.

For this reason, many electronic device manufacturers recommend removing the batteries from devices that will not be used for extended periods of time. Many types of batteries employ toxic materials such as lead, mercury , and cadmium as an electrode or electrolyte.

When each battery reaches end of life it must be disposed of to prevent environmental damage. E-waste recycling services recover toxic substances, which can then be used for new batteries.

The Battery Directive of the European Union has similar requirements, in addition to requiring increased recycling of batteries and promoting research on improved battery recycling methods. All packaging must be marked likewise. Batteries may be harmful or fatal if swallowed. While in the digestive tract, the battery's electrical discharge may lead to tissue damage; [65] such damage is occasionally serious and can lead to death. Ingested disk batteries do not usually cause problems unless they become lodged in the gastrointestinal tract.

The most common place for disk batteries to become lodged is the esophagus, resulting in clinical sequelae. Batteries that successfully traverse the esophagus are unlikely to lodge elsewhere. The likelihood that a disk battery will lodge in the esophagus is a function of the patient's age and battery size. Liquefaction necrosis may occur because sodium hydroxide is generated by the current produced by the battery usually at the anode.

Perforation has occurred as rapidly as 6 hours after ingestion. Many important cell properties, such as voltage, energy density, flammability, available cell constructions, operating temperature range and shelf life, are dictated by battery chemistry. On 28 February , The University of Texas at Austin issued a press release about a new type of solid-state battery , developed by a team led by Lithium-ion Li-Ion inventor John Goodenough , "that could lead to safer, faster-charging, longer-lasting rechargeable batteries for handheld mobile devices, electric cars and stationary energy storage".

Independent reviews of the technology discuss the risk of fire and explosion from Lithium-ion batteries under certain conditions because they use liquid electrolytes. The newly developed battery should be safer since it uses glass electrolytes, that should eliminate short circuits.

The solid-state battery is also said to have "three times the energy density" increasing its useful life in electric vehicles, for example. It should also be more ecologically sound since the technology uses less expensive, earth-friendly materials such as sodium extracted from seawater. They also have much longer life; "the cells have demonstrated more than 1, cycles with low cell resistance". The research and prototypes are not expected to lead to a commercially viable product in the near future, if ever, according to Chris Robinson of LUX Research.

A key hurdle that many solid-state electrolytes face is lack of a scalable and cost-effective manufacturing process," he told The American Energy News in an e-mail. Almost any liquid or moist object that has enough ions to be electrically conductive can serve as the electrolyte for a cell. As a novelty or science demonstration, it is possible to insert two electrodes made of different metals into a lemon , [71] potato, [72] etc.

A voltaic pile can be made from two coins such as a nickel and a penny and a piece of paper towel dipped in salt water. Such a pile generates a very low voltage but, when many are stacked in series , they can replace normal batteries for a short time.

Sony has developed a biological battery that generates electricity from sugar in a way that is similar to the processes observed in living organisms. The battery generates electricity through the use of enzymes that break down carbohydrates.

This is a process in which lead sulfate forms on the plates, and during charge is converted to lead dioxide positive plate and pure lead negative plate. Repeating this process results in a microscopically rough surface, increasing the surface area, increasing the current the cell can deliver. Daniell cells are easy to make at home. Aluminium—air batteries can be produced with high-purity aluminium. Aluminium foil batteries will produce some electricity, but are not efficient, in part because a significant amount of combustible hydrogen gas is produced.

From Wikipedia, the free encyclopedia. Redirected from Battery electricity. For other uses, see Battery. Various cells and batteries top-left to bottom-right:

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Terminal Voltage: Terminal Voltage of a cell or battery is the potential difference build between the two terminals of the cell/battery or load when a load is connected to the cell or battery or when a current is being drawn from the cell or battery.

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Aug 22,  · Next, you need to find the voltage drop across the internal resistance. You can use Ohm's law. Finally, you know how much voltage is being "lost" on the internal resistance, so you know what voltage will appear on the battery's terminals.

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Calculating Terminal Voltage, Power Dissipation, Current, and Resistance: Terminal Voltage and Load A certain battery has a V emf and an internal resistance of Ω. (a) Calculate its terminal voltage when connected to a Ω load. Why do battery and charger junction voltage is higher than charger or battery individual terminal voltage during charging? The sum of the voltages across each capacitor in a series is equal to the voltage of the battery.

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The term “voltage” in a battery refers to the difference in electric potential between the positive and negative terminals of a battery. A greater difference in potential results in a greater voltage. Terminal voltage definition is - the voltage at the terminals of an electrical device (as a battery or a generator). the voltage at the terminals of an electrical device (as a battery .