Definition and Function
– A battery is a source of electric power.
– It consists of one or more electrochemical cells.
– Batteries have positive and negative terminals.
– The positive terminal is the cathode, and the negative terminal is the anode.
– The flow of electrons occurs from the negative terminal to the positive terminal.
Types of Batteries
– Primary batteries are single-use and cannot be recharged.
– Secondary batteries are rechargeable and can be used multiple times.
– Examples of primary batteries include alkaline batteries.
– Examples of secondary batteries include lead-acid and lithium-ion batteries.
– Secondary batteries can be restored to their original composition by reverse current.
Size and Applications
– Batteries come in various shapes and sizes.
– They range from miniature cells for hearing aids to large battery banks.
– Battery banks provide standby or emergency power for telephone exchanges and data centers.
– Batteries have lower specific energy compared to gasoline.
– Electric motors in automobiles are more efficient in converting electrical energy to mechanical work.
History
– Benjamin Franklin first used the term battery in 1749.
– Alessandro Volta built the first electrochemical battery, the voltaic pile, in 1800.
– Early batteries had fluctuating voltages and couldn’t provide sustained large currents.
– The Daniell cell, invented in 1836 by John Frederic Daniell, became the first practical source of electricity.
– The Daniell cell was widely adopted as a power source for electrical telegraph networks.
Limitations and Corrosion Effects
– Early batteries had limited practical use due to voltage fluctuations.
– Michael Faraday showed that corrosion effects were unavoidable in battery operation.
– Volta mistakenly believed his cells were an inexhaustible energy source.
– The Daniell cell overcame some limitations of early batteries.
– Batteries have lower specific energy compared to common fuels like gasoline. Source: https://en.wikipedia.org/wiki/Battery_(electrical)
An electric battery is a source of electric power consisting of one or more electrochemical cells with external connections for powering electrical devices. When a battery is supplying power, its positive terminal is the cathode and its negative terminal is the anode. The terminal marked negative is the source of electrons that will flow through an external electric circuit to the positive terminal. When a battery is connected to an external electric load, a redox reaction converts high-energy reactants to lower-energy products, and the free-energy difference is delivered to the external circuit as electrical energy. Historically the term "battery" specifically referred to a device composed of multiple cells; however, the usage has evolved to include devices composed of a single cell.
 | |
| Type | Power source |
|---|---|
| Working principle | Electrochemical reactions, Electromotive force |
| First production | 1800s |
| Electronic symbol | |
.svg) The symbol for a battery in a circuit diagram. It originated as a schematic drawing of the earliest type of battery, a voltaic pile. | |
Primary (single-use or "disposable") batteries are used once and discarded, as the electrode materials are irreversibly changed during discharge; a common example is the alkaline battery used for flashlights and a multitude of portable electronic devices. Secondary (rechargeable) batteries can be discharged and recharged multiple times using an applied electric current; the original composition of the electrodes can be restored by reverse current. Examples include the lead–acid batteries used in vehicles and lithium-ion batteries used for portable electronics such as laptops and mobile phones.
Batteries come in many shapes and sizes, from miniature cells used to power hearing aids and wristwatches to, at the largest extreme, huge battery banks the size of rooms that provide standby or emergency power for telephone exchanges and computer data centers. Batteries have much lower specific energy (energy per unit mass) than common fuels such as gasoline. In automobiles, this is somewhat offset by the higher efficiency of electric motors in converting electrical energy to mechanical work, compared to combustion engines.
