What is an electronic cigarette

An electronic cigarette, e-cigarette or vaporize cigarette, is a battery-powered device that provides inhaled doses of nicotine or non-nicotine vaporized solution. It is an alternative to smoked tobacco products, such as cigarettes, cigars, or pipes. In addition to purported nicotine delivery, this vapor also provides a flavor and physical sensation similar to that of inhaled tobacco smoke, while no smoke or combustion is actually involved in its operation. An electronic cigarette takes the form of some manner of elongated tube, though many are designed to resemble the outward appearance of real smoking products, like cigarettes, cigars, and pipes.
Another common design is the "pen-style", so named for its visual resemblance to a ballpoint pen. Most electronic cigarettes are reusable devices with replaceable and refillable parts. A number of disposable electronic cigarettes have also been developed.

The electronic cigarette was invented by a Chinese medicine practitioner Hon Lik in China in 2003 and introduced to the market the next year. The company he worked for, Golden Dragon Holdings, later changed its name to Ruyan (meaning "to resemble smoking") and started selling abroad.

Operation

In automatic models, when a user inhales through the device, air flow is detected by a sensor, which activates a heating element that vaporizes a flavored liquid solution stored in the mouthpiece, which may contain nicotine. On manual models, the user must depress a button to activate the heating element to produce vapor which is then inhaled by the user. On most models an LED on the opposite end of the device is also activated during inhalation, which serves as an indicator of use. Several LED colors are available from various manufacturers.

Components

While electronic cigarettes take many forms, they each generally employ the same basic components: a mouthpiece, a heating element, a rechargeable battery, and various electronic circuits.

Mouthpiece ("cartridge")
The mouthpiece is a small disposable plastic cup-like piece affixed to the end of the tube. Inside the mouthpiece is a smaller plastic cup which holds an absorbent material that is saturated with a flavored liquid solution. The level of nicotine varies depending on the solution. This inner cup is made such that air is able to flow around it and through a hole in the end of the outer piece; this is necessary for the device to provide the ability for suction to move the vapor into the user's mouth. The mouthpiece is referred to in the industry as a "cartridge". When the liquid in the cartridge has been depleted, it can either be refilled by the user or replaced with another pre-filled cartridge.

Heating element (atomizer)
The heating element serves to vaporize the liquid in the mouthpiece so that it can be inhaled. This component is referred to in the industry as an "atomizer". Atomizers have a finite life of about 6 months (on average) and are one of the recurring expenses associated with electronic cigarettes. Some models combine an atomizer and pre-filled disposable component referred to as a "cartomizer".

Batteries and Electronics

Most electronic cigarettes employ a lithium-ion rechargeable battery to power the heating element. Battery life varies depending on the battery type and size, frequency of use, and operating environment. Many different battery charger types are available, such as wall outlet, car, and USB chargers. The battery is generally the largest component of an electronic cigarette.

Traditionally, electronic cigarettes have utilized an electronic means of activation. This involved the use of small tactile switches, vacuum switches and the related wiring and electronics necessary to run them. Users soon discovered these could be unreliable. With the advent of "mods", several manufacturers have created all-mechanical electronic cigarettes that eliminate the use of any wiring, solder or electronics in an effort to improve switch reliability.

While some larger electronic cigarette models employ a user-replaceable standard-size battery cell, many models are too small to house a standard-size cell and instead require a proprietary component made by the electronic cigarette manufacturer. For those models, the battery and electronic components are housed within a single replaceable part, which is still generally referred to in the industry simply as the "battery".

There have been some recent developments with the implementation of mobile phone battery technology into this market sector allowing the electronic cigarettes batteries to be charged on the go in a crumple proof box known as a Personal Charging Case. The rechargeable battery inside the Personal Charging Case allows the user to charge the battery stems inside the case and store the replacement cartomisers/cartridges too. The recharging box/case is also the same size as a packet of traditional tobacco cigarettes.

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