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n electric battery is a device consisting of one or more electrochemical cells that convert stored chemical energy into electrical energy.[1] Each battery consists of a negative electrode (anode) that holds charged ions, a positive electrode (cathode) that holds discharged ions, an electrolyte that allows ions to move from anode to cathode during discharge (and return during recharge) and terminals that allow current to flow out of the battery to perform work.
Batteries are either primary (single-use or "disposable") that are used once and discarded or secondary (rechargeable batteries) that are discharged and recharged multiple times.
Batteries are made from many materials including various metals, carbon, polymers and even air. The most common are lead-acid batteries used in vehicles and lithium ion batteries used for portable electronics. Batteries come in many shapes and sizes, from miniature cells used to power hearing aids and wristwatches to battery banks the size of rooms that provide standby power for telephone exchanges and computer data centers.
Batteries have recently[when?] received significant research and development, because they are hoped to provide a solution for energy storage in a transition from fossil fuels to alternative energy, both for transport and electricity production and for powering portable devices of all kinds.[citation needed]
Billions of batteries are used each year to power devices as diverse as automobiles to mobile phones.According to a 2005 estimate, the worldwide battery industry generates US$48billion in sales each year,[2] with 6% annual growth.[3] Baterai Laptop

In strict terms, a battery is a collection of multiple electrochemical cells, but in popular usage battery often refers to a single cell.[1] For example, a 1.5-volt AAA battery is a single 1.5-volt cell and a 9-volt battery has six 1.5-volt cells in series. The first electrochemical cell was developed by the Italian physicist Alessandro Volta in 1792, In 1800 he invented the first battery, a "pile" of many cells in series.[4]
The usage of "battery" to describe electrical devices dates to Benjamin Franklin, who in 1748 described multiple Leyden jars (early electrical capacitors) by analogy to a battery of cannon.[5] His term to describe multiple Leyden jars predated Volta's use of multiple galvanic cells.[6] It is speculated, but not established, that several ancient artifacts, consisting of copper sheets and iron bars and known as Baghdad batteries may have been galvanic cells.[7] Baterai Laptop Murah
Volta's work was stimulated by the Italian anatomist and physiologist Luigi Galvani, who in 1780 noticed that dissected frog's legs twitched when struck by a spark from a Leyden jar, an external source of electricity.[8] In 1786 he noticed that twitching also occurred during lightning storms.[9] After many years Galvani learned how to produce twitching without an external source of electricity. In 1791, he published a report on "animal electricity."[10] He created an electric circuit consisting of the frog's leg (FL) and two different metals A and B, each metal touching the frog's leg and each other, thus producing the circuit A–FL–B–A–FL–B...etc. In modern terms, the frog's leg served as both the electrolyte and the sensor, and the metals served as electrodes. He noticed that even though the frog was dead, its legs twitched when touched with the metals.
Within a year, Volta realized the frog's moist tissues could be replaced by cardboard soaked in salt water, and the frog's muscle response could be replaced by another form of electrical detection. He already had studied the electrostatic phenomenon of capacitance, which required measurements of electric charge and of electrical potential ("tension"). Building on this experience, Volta was able to detect electric current through his system, also called a Galvanic cell. The terminal voltage of a cell that is not discharging is called its electromotive force (emf), and has the same unit as electrical potential, named (voltage) and measured in volts, in honor of Volta. In 1800, Volta invented the battery by placing multiple cells in series, piling one above the other. This voltaic pile gave a greatly enhanced net voltage (electromotive force) for the combination,[11] producing about 50 volts from a 32-cell pile.[12] In parts of Europe batteries continue to be called piles.[13][14] Baterai Laptop malang
Volta did not appreciate that the voltage was due to chemical reactions. He thought that his cells were an inexhaustible source of energy,[15] and that the associated corrosion effects at the electrodes were a mere nuisance, rather than an unavoidable consequence of their operation, as Michael Faraday showed in 1834.[16] According to Faraday, cations (positively charged ions) are attracted to the cathode,[17] and anions (negatively charged ions) are attracted to the anode.[18]
Although early batteries were of great value for experimental purposes, their voltages fluctuated and they could not provide significant current for a sustained period. Later, starting with the Daniell cell in 1836, batteries became more reliable and were adopted by industry for use in stationary devices, in particular in telegraph networks where they were the only practical source of electricity, since electrical distribution networks did not yet exist.[19] These wet cells used liquid electrolytes, which were prone to leakage. Many used glass jars to hold their components, which made them fragile. These characteristics made wet cells unsuitable for portable appliances. Near the end of the nineteenth century, the invention of dry cell batteries, which replaced the liquid electrolyte with a paste, made portable electrical devices practical.[20]
Since then, batteries became portable and useful for many purposes.[21]