Mobile phone charger
Mobile Charger |
Most mobile phone chargers are not really chargers, only power adapters that provide a power source for the charging circuitry which is almost always contained within the mobile phone. Older ones are notoriously diverse, having a wide variety of DC connector-styles and voltages, most of which are not compatible with other manufacturers' phones or even different models of phones from a single manufacturer.
Users of publicly accessible charging kiosks must be able to cross-reference connectors with device brands/models and individual charge parameters and thus ensure delivery of the correct charge for their mobile device. A database-driven system is one solution, and is being incorporated into some designs of charging kiosks.
Mobile phones can usually accept a relatively wide range of voltage, as long as it is sufficiently above the phone battery's voltage. However, if the voltage is too high, it can damage the phone. Mostly, the voltage is 5 volts or slightly higher, but it can sometimes vary up to 12 volts when the power source is not loaded.
There are also human-powered chargers sold on the market, which typically consists of a dynamo powered by a hand crank and extension cords. A French startup offers a kind of dynamo charger inspired by the ratchet that can be used with only one hand. There are also solar chargers, including one that is a fully mobile personal charger and panel, which you can easily transport.
China, the European Commission and other countries are making a national standard on mobile phone chargers using the USB standard. In June 2009, 10 of the world's largest mobile phone manufacturers signed a Memorandum of Understanding to develop specifications for and support a microUSB-equipped common External Power Supply (EPS) for all data-enabled mobile phones sold in the EU.[19] On October 22, 2009, the International Telecommunication Union announced a standard for a universal charger for mobile handsets (Micro-USB)
Battery
A popular early mobile phone battery was the nickel metal-hydride (NiMH) type, due to its relatively small size and low weight. Lithium ion batteries are also used, as they are lighter and do not have the voltage depression due to long-term over-charging that nickel metal-hydride batteries do. Many mobile phone manufacturers use lithium–polymer batteries as opposed to the older lithium-ion, the main advantages being even lower weight and the possibility to make the battery a shape other than strict cuboid
Battery
Mobile Battery |
Power supply
Mobile phones generally obtain power from rechargeable batteries. There are a variety of ways used to charge cell phones, including USB, portable batteries, mains power (using an AC adapter), cigarette lighters (using an adapter), or a dynamo. In 2009, the first wireless charger was released for consumer use. Some manufacturers have been experimenting with alternative power sources, including solar cells
Various initiatives, such as the EU Common External Power Supply have been announced to standardize the interface to the charger, and to promote energy efficiency of mains-operated chargers. A star rating system is promoted by some manufacturers, where the most efficient chargers consume less than 0.03 watts and obtain a five-star rating.
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