What components are included in the vapor of the electronic cigarette? The most important things to learn about the components within the vapor of electronic cigarettes are that the nicotine within the products remains - but there are more important components which have been removed from the cigarette.

Mouthpiece ("cartridge")

The mouthpiece is a tiny disposable plastic cup-like piece affixed to the finish of the tube. Inside the mouthpiece is a smaller plastic cup which holds an absorbent material that is saturated with a flavored liquid solution that may contain nicotine. This inner cup is made such that air can flow around it and through a hole in the finish of the outer piece; this is necessary for the device to provide the ability for suction to move the vapor in to 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.

As an alternative to the traditional plastic mouthpiece, some manufacturers have created dedicated mouthpieces for dripping, such as Super-T manufacturing's stainless steel T-Tip drip tip.

Another alternative to using cartridges is the direct dripping technique using drip tips. By removing the absorbent material, one can basically remove the plastic mouthpiece and drip several drops of e-liquid directly onto the atomizer bridge. To further ease dripping, some manufacturers have created specialty mouthpieces made of stainless steel or plastic that are intended for dripping and do not need removal each time you drip.

Heating element ("atomizer")

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

Battery and electronics

An electronic cigarette battery connected to a USB charger.

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 surroundings. Lots of different battery charger types are available, such as wall outlet, automobile, and USB chargers. The battery is usually the largest part of an electronic cigarette.

Some electronic cigarettes employ an electronic airflow sensor to automatically activate the heating element on inhalation, while other models require the user to press a button while inhaling. Various other electronic circuits are usually employed as well, such as a timed cutoff switch to prevent overheating as well as a colored LED to signal activation of the gizmo.

Mostly, 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 a hard work to improve switch reliability.

While some larger electronic cigarette models employ a user-replaceable standard-size battery cell, lots of models are small to house a standard-size cell and in lieu require a proprietary part made by the electronic cigarette manufacturer. For those models, the battery and electronic parts are housed within a single replaceable part, which is still usually referred to in the industry basically as the "battery".