Vaping Terminology

A list of terms used in the world of vaping to describe e-cigarette (or more accurately EV, electronic vaporizer) hardware, refills and usage.

actuator/contactor button: the on/off button on a mechmod (an all-mechanical PV with no wiring). Actuator is a more accurate term than ‘switch’, because these APVs have no wiring and therefore no switch, in the generally accepted sense that a switch is a wired-in electrical device. Actuators are a simple contactor that commonly uses a spring-loaded pin or lever or other contact-making method; they are frequently fitted in the negative line (unlike most electrical switches) since it is mechanically easier on some designs, especially tubemods.  
   Several types of actuators are in use. In rough order of invention/use, they are: a sliding top end section depressed by the thumb or mouth, as used on early copper tubemods using water pipe; a bottom end button, in use continuously on tubemods since the earliest commercial devices (e.g. the Screwdriver); a boxmod top button (e.g. Reo); a bottom end side actuator button (e.g. XHaler); a top end side actuator button in a separate switching section using magnets for the pushback (e.g. Poldiac).

adapter: a connector that allows a head with a given thread connector system to fit on to a body (battery holder) with a different connector; or to create extra length in the head system. Common adapters are 510-to-510 (for use of an atomizer and dripshield, or to save wear on the body connector), 510-to-eGo (to allow a twin-thread eGo head to fit a regular 510 battery holder), 510-to-KR8, 510-to-801, 901-to-510. As the benchmark connector system is now the 510, most adapters feature a 510 battery end with another connector system at the head end.

aerosol: a technically more accurate description of e-cigarette ‘vapour’, because of the presence of liquid droplets suspended in air.

all-day vape, ADV: a flavor of e-liquid that a person finds acceptable to use for most or all of the day for an extended period of weeks or months. In general an all-day vape is not going to be a radical flavor, it will be probably be something not too far from the norm, possibly a tobacco variant and possibly a caramel or vanilla style of flavour; it is usually a flavor that many people find acceptable. The archetypal all-day vape is RY4, an early but still popular caramel-vanilla tobacco flavour, on which there are now hundreds (possibly thousands) of variations.

analog : (slang) an ordinary tobacco cigarette. The implication is that as the digital / electronic version is the ecig, the analogue version is the cigarette. The US spelling for ‘analog’ is always used (just as with ‘program’, a software routine).

anhydrous glycerine: glycerine with no measurable water content. Of limited benefit in refill manufacture since water must be added in order to reduce the viscosity, to render it usable; perhaps it is supposed to represent greater purity. Sometimes abbreviated to AG, but this term is also used for a different (perhaps ‘opposite’) material, aqueous glycerine (glycerine with significant water content); therefore the abbreviation AG should never be used as it is confusing and non-specific.

APV: advanced personal vapouriser (or mod), a 2nd-generation or later improvement on the mini (a regular small-format ecig), with a much larger battery or batteries and often some additional features such as higher voltage or variable voltage. An APV can be defined as (1) a battery holder for generic batteries; or (2) as a vaping device that has removable generic batteries and/or features additional to those found on minis; or (3) a large, multi-feature PV.
   The older term ‘mod’ was used because such large-battery devices could not be purchased but had to be created by modifying (‘modding’) a torch/flashlight or similar. APVs are the largest of the three main classes of e-cigarette (mini, mid-size and APV). APVs are 2nd-generation and later e-cigarettes that have at least three times the performance of a mini, often with additional functions. They offer a multitude of features including large battery performance, stainless steel high-quality construction, digital readouts, high voltage, variable voltage, variable power, integral liquid feed, fine wood construction with marquetry, and so on.
   APVs are available in 2 formats and 3 classes. The 2 common formats (shapes) are boxmods and tubemods: box format devices that generally look like a cigarette pack with a mouthpiece, and may be formed from billet metal, plastic, or be of fine decorated wood; or tubular format devices that usually look like a small flashlight with a mouthpiece at the top, and are commonly stainless or colour-coated metal in construction. The 3 classes are (1) mechmods: fully-mechanical devices that are essentially just battery holders, with a mechanical actuator switch and no wiring or electronics; (2) basic electrical devices: simple battery holders with a wired positive line including an electrical switch; and (3) electronic devices: battery holders with electronic controls such as VV chips.
   The first use of the term APV is thought to have been to describe the Zen mechmod (also referred to as a ‘hybrid’).

aqueous glycerine: (see anhydrous glycerine)

atomiser: (1) the heater coil that nebulises the refill liquid; or (2) an ‘atty’: the complete atomiser unit from a 3-piece e-cigarette that comprises a steel tube 9mm in diameter (for the 510 model) containing the atomiser coil, bridge, threaded connector system with airhole at one end, and an open end at the other for connection of a cartridge or (more recently) a driptip. The original 510 atty was 9mm dia x 23mm long (27.5mm inc. thread connector), later models tended to be longer.
   An atomiser is in fact misnamed since in reality it is a nebuliser. In function, it can be described as a combination of the heater element in a toaster combined with an electric kettle: the coil heats up but must be immersed in liquid, or a heavily saturated atmosphere, to cool it or it will overheat. Since the liquid replacement is by gravity feed in a regular atomiser, it is like an electric kettle in that it will not work upside down: with no liquid cooling, it will overheat, go into out-of-parameter operation (overheat), and eventually fail.
   A regular atomiser operates at around 60 to 70 degrees Celsius. Without liquid cooling it will go to 300 C or so, and eventually fail. At these sorts of temperatures, the device will generate smoke from melting internal components; it cannot produce vapour since there is no liquid left if the temperature has risen to this value.

automatic: a mini ecig with an air pressure activated switch not a manual button, so that the vacuum created by the user drawing on it pulls air through and operates the device, thereby making it a functional replica of a tobacco cigarette; or (b) the battery itself, as this contains all the operating elements and is self-contained. A mini ecig battery can be automatic or manual. Automatics are highly sensitive to leaking e-liquid, which causes them to fail, and means they are far less reliable than manual devices. Recently a ‘sealed’ automatic system has been devised; reliability data is awaited.
   The early automatics also utilised a mic cartridge for operation: a microphone and electronic switching that operated when the sound of air passing through was detected. Needless to say, this resulted in unwanted operation when background noise levels were high, such as in a moving car (and especially trucks). This system was used because it is less sensitive to liquid damage than the pressure switch arrangement; but in the end it was found that frequent failures were preferable to unstable operation.

battery: (‘batt’), the rechargeable electrical storage device that provides the power source for a personal vapouriser (‘e-cigarette’). A disposable item. See also: lithium ion cell.

battery cutoff: auto batteries normally have a time limit on the operation cycle, to prevent pocket operation and burnout. The time cutoff may be from 6 to 12 seconds. A secondary cutoff may be in place that limits total operational time in an overall period such as 2 minutes. Auto batteries are not popular with ex heavy smokers, partly because of this reason; some models may limit usage time too strictly, especially since primer puffs (qv) are often needed on these tiny units.

BCC: bottom coil clearomiser – the later type that features the coil within the base of a (usually) replaceable cartridge comprising the coil, wick, and centre air channel. BCC could also be used for a regular carto with a bottom coil, but this is not common (the first bottom coil carto produced was a regular Boge 9mm x 35mm carto with the atomiser coil at the base instead of vertical and central; then the system was used on other heads and so BCC now refers to clearos).

BDC: bottom dual coil clearo (see above).

best atomiser: vapers love to argue about what device gives the best vape. Because in matters of taste there can be no winner (what is the best for one person is not another’s favourite), this is an impossible question to answer. In the traditional atomiser types, the 306 (a 510 variant), 801, 510 and 901 all have their followers. Various clearos and uprated cartos have their proponents. More recently, the RBAs have converted many.
   If one specific aspect of the vape is being considered, it is easier to find good candidates; for example, if vapour volume is the key factor, nothing can beat an RBA, but the vapour is drier than with other atomisers. If a rich vape is preferred (moist with high flavour) then the older atomiser models such as the 306 (dripped) are top scorers. If a cool, hassle-free vape is preferred, the clearos win out.

bonuts: an atomiser mod that increases the amount of liquid that can be dripped on to an atomiser. In practice, the direct opposite of de-bridging as it increases the amount of SS wick; and thus made possible by VV devices that can increase the voltage fed to the atomiser to compensate for the increase in thermal inertia (the cooling effect caused by holding more liquid adjacent to the heater coil.
   A bonut is made by taking a stainless pipe screen, rolling it into a thin tube of about 2mm thickness, then bending the tube and forming it into a ring (it actually assumes a horseshoe shape). A pipescreen is an 18mm diameter circular piece of mesh made from stainless steel woven thread, the most common source being Ebay; do not use brass screens.
   The mesh is then inserted into an atomiser and pressed downward to sit around the heater coil and bridge. Another bonut is then inserted for a total of two; some users insert three although this is a tight fit in a 510 atty.
   The complete bonut dripper rig comprises for example a 510 atomiser, with two bonuts inserted, a driptip, a solid 510-to-510 adapter, and a dripshield. The dripshield is an external sleeve that stops any leakage. This rig allows 8 or 10 drops to be dripped into a clean, dry setup. No leakage occurs as the dripshield covers all exit points. Top-ups are from 3 to 5 drops as required. This rig provides a hassle-free high-capacity drip rig; some claim dripping as the ultimate vape.
   The bonut was invented by ECF modder BJ43. He named it the SS donut, then admirers changed it to bonut by inserting the B from his web handle. A bonut dripper rig allows a user with a VV device to drip less frequently, with zero leakage, and to get the vapour experience required by turning up the voltage to compensate for the uprated liquid load.

bridge: the wire mesh arch that is positioned above the heater coil in a regular atomiser. Sometimes the (usually stainless steel) mesh contains a silica wick. The purpose of the bridge was originally to protect the coil from the cartridge wadding, to transfer the refill liquid downward by gravity, contact and capillary action, to hold some refill liquid in close proximity to the coil, and to limit downward transfer of the liquid to avoid flooding the coil. The bridge in modern atomisers is mainly there to hold liquid for nebulising, and it contributes to creating a liquid-saturated atmosphere around the coil.

cartomiser (‘carto’):, a combined atomiser and cartridge that contains both the heating element and the liquid reservoir. A disposable item. Generally, a carto has a central, vertical atomiser coil within a central air channel formed by a roll of silica cloth, surrounded by polyester wadding that holds and stabilises the refill liquid. This is topped by a disc or discs to prevent leakage, and finally a top plug, all having a central air hole of about 1.5mm.
   The carto has replaced the atomiser + cartridge (with the battery, this formed the 3-piece ecig) as the most common e-cigarette head unit, and thus, with the battery, forms part of the 2-piece ecig system: the basic format for not only the 2-piece mini but larger models as well (though heads vary widely, in larger models). The carto was invented by Kanger for the KR808 system, and the benchmark carto is their 9mm x 35mm KR8 model; replicated by Boge and others in 510 etc.
   A regular carto of 9mm x 35mm contains 1ml of refill liquid. About 80% of this can be used, since about 20% is retained by the filler wadding. Expert users generally report that a regular carto containing 0.8ml usable liquid is equivalent to around 6 cigarettes (this is a subjective measure and cannot be calculated by any valid numerical method).
   Cartos can be refilled and reused around 5 times before they need cleaning or disposing of. They can be cleaned about 3 times before their performance is too poor to continue use. Therefore it is theoretically possible to obtain around 15 x 6 ‘cigarette equivalent sessions’ from a standard carto – for the financially challenged or the dedicated hobbyist. Most users of mini ecigs are either not aware that cartos can be refilled, or do not want the hassle of refilling, and simply dispose of their pre-filled cartos after single use.
   Mini ecigs use a standalone carto, which conveniently replicates the filter part of a tobacco cigarette in size and shape. Otherwise, the more efficient and capable mid-size and APV models normally use the carto within a tank: a normally transparent sleeve that slides on to the carto and provides an additional reservoir of refill liquid that feeds into the carto, which must be perforated near the base for this duty. Tanks normally vary between 4ml and 7ml capacity. A tank must be refilled from a bottle of refill liquid.

carto condom the silicone plastic endcap placed over the ends of a carto to stop leakage and keep the product fresh.

charger: the battery charger that replenishes a discharged ecig battery. The original chargers for 1st-gen equipment featured a mains electricity plug with cord connected to a DC 4.2 volt charger unit of around 100mAh with appropriate thread for the mini ecig battery to screw on to. A red and green light on the charger revealed the charge state of the battery – red for on charge, green for fully-charged.
   Chargers for 2nd-gen midsize batteries were the same but with larger outputs. They had a larger connector port for the eGo-size batteries to screw into, though the thread connector was the same. A mid-size battery needs a charger adapter in order to fit a mini charger; the adapter is simply a slimmer connector end; the charge rate qualifies as a trickle charge whn used on the larger battery. Then came mini USB connector charging ports at the battery base. There is a user-error danger here: devices with a USB charger port may not charge correctly if the top connector thread is used for charging: only the device-specific charger should be used.
   APV batteries are normally recharged by removing the cells then placing them in the tray of a generic lithium cell charger, a typical model being the Trustfire TR-01 (called the ‘TR1′). An IMR cell can be recharged at 500mAh in these, and some have a 1-amp rapid recharge facility. The TR1 takes two 3.7 volt lithium cells of 10430, 10440, 14500 (AA cell size), 16340 (RC123a size), 17670, 18500, or 18650 size. Other chargers can take up to 26500 (‘D’ cell size) or 26650 lithium cells.
   Chargers generally have a 12 volt jack for in-car use, and can handle a range of mains voltages and frequencies (typically 110v to 240v, 50Hz to 60Hz). US mains voltage is 110v and 60Hz AC, EU voltage is 230v and 50Hz AC.
   Some APVs have an integral battery pack and must be charged using a mini USB port.

clearomiser (‘clearo’): a large, clear cartomiser, one of the most popular head systems now. The clearo is a 2nd-generation carto (and thus 3rd-gen gear) and is larger and has no wadding, being (initially) a simple tank with a silica wick system feeding a top coil atomiser. Later models feature other operational methods such as bottom coil replaceable cartridges.
   A typical model is the CE4. They commonly hold from 1.7ml to 3ml of refill liquid. They must be refilled from a bottle. A disposable item, they are generally refilled several times then disposed of when performance falls off. The later models may have replaceable atomiser cartridges, to prolong service life. Cracking is an issue with these units (qv).

coil: the nichrome heater coil that nebulises the refill liquid; the atomiser coil. In a regular atomiser, the coil is wound around a short length of silica wick in a coil af around 1.5mm diameter (this is termed a micro coil as other types have a larger diameter). In an RBA, either nichrome or kanthal wire is used. All coils use resistance wire that is designed to have a specific resistance per unit length (normally expressed as Ohms per inch or cm).
   The coil must be either immersed in liquid or a saturated atmosphere otherwise it will overheat. A coil runs at a normal temperature of 60 to 70 degrees Celsius. The refill liquid is nebulised by the combination of a heater coil and air throughput, and turns into an aerosol, a process that is enhanced by use of an excipient (a solvent or carrier liquid) such as PG. In order that the coil temperature remains low, liquid that has been nebulised must be immediately replaced, a process accomplished by various methods normally using some form of wick.
   If the coil is operated without the presence of liquid it will overheat and pass through 300 C to a red-heat temperature (assuming sufficient power is available, which is not always the case). At this point, internal components of the atomiser will be melting and smoke is produced. There is no vapour at this point because in order to reach this temperature there cannot be any liquid present. A human cannot inhale this smoke although laboratory testing machines cannot tell the difference (where toxic components have been measured in the ‘vapour’, they are clearly pyrolytic compounds and generated by out-of-parameter operation).

cracking: clearos and any other tanks that use plastic window material are subject to cracking and leakage due to attack from citric acid and other components in e-liquid. This aggressive etching is caused by a wide range of flavourings. It is not clear if the effect is caused by the leaching of plasticisers (e.g. pthalates). Some plastics are more resistant than others, but only pyrex glass and quartz are totally resistant to liquid attack; however they are more vulnerable to impact damage. We do not know, however, if genuine cobalt glass Pyrex is used (Pyrex in the UK uses genuine toughened cobalt glass), or the cheaper versions (‘pyrex’ in other locations does not use cobalt glass). Genuine cobalt Pyrex is highly resistant to impact damage, chemical attack and thermal shock.

DCC: dual coil cartomiser, a long carto of 9mm x 51mm in which two atomiser coils are used and the final resistance is commonly 1.5 ohms. These cartos are known for strong performance though they drive the battery harder.

doubler: flavour doubler liquid is a refill type containing no nicotine but base and flavouring only that can be used to reduce the refill strength by adding the doubler: the nicotine strength drops in proportion but the flavour stays constant. It can also be used to replace the flavour lost when the original liquid is modified or stretched in other ways; tripler liquid has extra-strength flavour for this purpose.

dry hit: the first draw taken after refill liquid runs low is termed a ‘dry hit’: it will consist of low vapour volume, with hot, thin vapour and a noticeably dry quality to the vape. It is important that no further usage occurs until the device is refilled or replaced, since the next hit will burn the internals of the head and may render it unusable. In addition the product may be smoke and not vapour.

dry burn: a technique for cleaning an atomiser coil that has become encrusted with carbonised material (‘coked-up’). Any source of liquid feed is removed, and the on button is held down while the coil is observed, the button being released the moment the coil reaches red heat, and the process is repeated several times. The atomiser is then flushed with a solvent such as ethanol (plain vodka is commonly used).
   The process may or may not work: it usually leaves a burnt taste because the wick surface is singed and blackened: whether or not this can be removed by the solvent flush is critical. If not, a permanent burnt taste is left, and the atomiser must be disposed of. If it does work, it is frequently the only way to clean a heavily-used atty.
   Atomisers tend to coke up in proportion to lower voltage and higher flavour load. Therefore, the fastest to coke up are mini ecigs (as they run at very low power) with highly-flavoured and especially dark-coloured refills. The least affected by coke on the coil are 5 volt or VV devices run at 5 volts or so, using lightly-flavoured clear refills. Therefore, it can be seen that atomiser coking was a far greater issue in the past than today.
   A dry burn cannot be used in a carto, as the filler wadding is burnt as a result and cannot be effectively cleaned. A coked-up carto must be disposed of.

ECF: the E-Cigarette Forum, which was both the starting point for and the catalyst for the growth of the vocal and engaged online ecig community. ECF was the first forum and is the largest. It had millions of posts before any great interest in ecigs was shown by the pharmaceutical and cigarette industries, and therefore the notion that the ecig community does not exist or is an astroturf product of the tobacco industry is found to be hilarious by the community. To be fair, it may be unique: the ecig community appears to be alone among users of similar products, foods or drinks; it is certainly unique in both its engagement and highly-vocal defence of ex-smokers’ rights. It is determined to make free choice of alternatives to smoking a voting issue, and appears to be successful in the early stages of that campaign; the potential is for 20% of voters to be swayed by the campaign and it is therefore not a trivial issue.
   Started in 2007 by Londoner Oliver K, the first Admins were Kate (UK) and Spikey (NY), who are still active in the community. For the first year it was a mainly UK-based community; the second year saw more US members join, and from then on it became principally a US-based board and was moved from the UK to US web hosting in 2010. At its peak, about 80% of traffic was from the USA, but this is now gradually falling as the rest of the world catches up, with US traffic now below 70%. ECF was managed from the earliest to be a respectable, work-safe and family-safe environment, which may help to explain the significant number of doctors, medical researchers and public health staff who are members.
   ECF is run on a dedicated server cluster that handles high traffic (heavily-loaded forums cannot be run on cloud resources because there are thousands of database read/writes per second, which is impossible for a distributed server group to handle; a major forum is the hardest server load in existence). There are multiple micro-sites on the same server cluster that present other content such as a wiki, ecig jobs board, (product) coupons, and so on. The cost is mainly borne by subscription and advertising by the ecig industry. One of the principal successes has been the way the commercial and community requirements have been balanced and are always weighted toward the community.
   ECF is the largest ecig community, the world’s largest e-cigarette marketplace, the largest information resource, the centre of ecig campaigning, and has the best health and technical resources. The community includes chemists, lawyers and doctors who help the community in their respective fields. At Q1 2014 there are around 3,500 visitors online daily across the site at peak times, the figure jumping to 10,000+ when a news item breaks.

EV: electronic (or electric) vapouriser. Probably the most accurate term for an ecig, but not widely used.

e-liquid: the common term for e-cigarette refill liquid. Also ‘e-juice’.

e-cigar: an EV made to resemble a cigar in looks and flavour. The e-liquid used would typically be a cigar type such as Cuban or Cherry Cigar flavour, to stay in character.

e-cigarette: electronic cigarette, or more accurately an EV or electric/electronic vapouriser.

electronic cigarette: (see – E).

de-bridge, de-wick: a modification of atomisers popular before VV devices removed the need for such action. First generation ecigs were inefficient devices limited to battery voltage (nominally 3.7v) and usually with batteries also too small too deliver any realistic power without significant voltage drop. The optimum working parameters of an atomiser are above the voltage and current that a small Li-ion cell can deliver, therefore until the advent of regulated devices, performance was sub-optimal: essentially, the vape was too cool, too limited in volume, too limited in throat hit, and too limited in alkaloid delivery performance. De-bridging was an attempt to rectify this by removing one factor that added to atomiser cooling: the bridge, which often contained a silica wick. By doing this, the vape could be heated slightly.
   This practice began to become redundant when 5 volt APVs were developed by the modders on ECF since 5v devices have no need for atomiser modification; when the 3rd generation ecigs (VV devices) became universal there was no longer any need to control vape parameters by mechanical alterations, since full electronic control provides all the variation needed.

dripping: to drip liquid on to an atomiser instead of feeding it by some other method. It produces the richest flavour and most moist vapour; but is fiddly and inconvenient except for aficionados. By using a dripshield and bonuts, the frequency of dripping can be reduced, though (see bonuts).

dripshield: a sleeve that slides down over an atomiser in order that dripping can be freely accomplished without leakage. (also see bonuts)

driptip: a removable mouthpiece. Originally named for a specific type with a larger internal bore so that liquid could be dripped down through it onto an atomiser without having to remove the mouthpiece. The benchmark model is of 9mm connector diameter to fit a 510 or KR808 carto. The connection employs a sliding fit sealed by an O-ring, so the tip can be easily fitted or removed. Most driptips are of circular format but some, notably the 901 and 510 DC carto models, use the ‘whistle tip’ flat format as used on a briar (tobacco) pipe.
   When actually used for dripping, some users remove the tip then drip on to the atomiser, some drip straight through it.

head: any atomiser, liquid reservoir and mouthpiece or combination that is attached to an e-cigarette battery at the user end. The part of the device that holds and nebulises the refill. Modern heads tend to be one-piece units that fulfill all the required non-battery jobs, though they may break down into their separate components; the mouthpiece is almost always a removable/replaceable component. The benchmark head at Q1 2014 is the clearomiser; cartos, atties, and RBAs are also heads.

head (2): sometimes used for the replaceable cartridge within a clearomiser that contains the atomiser, wick and central air channel.

hybrid: a type of APV, normally a mechmod with integrated battery tube, reservoir tank and RBA. Examples: some GG models, some Zen models. The device is commonly a stainless tubemod with an RTA (i.e. a tank + RBA) made to fit exactly, so that it has the same diameter, construction and styling as the battery tube; usually the actuator is a bottom button.

lithium cell types: electronic cigarettes use lithium ion cells (rechargeable lithium batteries) because of their high voltage and high charge density. Rechargeable batteries are also called secondary cells (standard batteries, that are not rechargeable, are called primary cells). Varying types of lithium ion cell are used; all except ‘Li-Fe’ cells have a nominal voltage of 3.7 volts. Mini ecigs use ‘Li-ion’ cells: lithium cobalt oxide LiCoO2; these are generally referred to as ‘unprotected Li-ions’. They need an add-on protection circuit to prevent overcharging / over discharge / excess current discharge, otherwise the cell is too unstable for consumer product use. Either the e-cigarette device contains the protection circuit, or the circuit is provided in the form of an add-on disk-shaped circuit board appended to the negative pole (the bottom) of the battery (this generally applies to 14500 series cells and larger). Mid-size ecigs (eGo type) also use a Li-ion cell, with the added protection circuit within the device. APVs, the large-format devices, use replaceable generic batteries and this allows the use of more efficient and safer cells. Typically, an Li-Mn cell is used: lithium manganese, aka IMR. These are a ‘safer-chemistry’ type that has no need of a protection circuit. Some of these larger devices may use Li-FePo4 cells (‘Li-Fe’ or lithium ferrous cells); these have a lower nominal voltage of 3.2 volts and are also of the safer-chemistry type. Some integral battery pack devices use ‘Li-Poly’ cells, which are lithium polymer cells.

lithium ion cell: the correct term for a lithium rechargeable battery or ‘Li-ion’ battery. The nominal voltage is 3.7 volts. All e-cigarettes except for one design available for DIY (the ‘Puck’, which uses regular 1.5 volt rechargeables) use a lithium ion cell or cells. The size ranges from the tiny cells in the minis, of around 90 to 125mAh (milliamp/hour) to the 1,600 or 2,000mAh cells (18650 series) used in many APVs. Some XL devices use a 26650 series cell. The cell # delineates the physical size and type: an 18650 for example means 18mm diameter, 65mm length, round format.
   All batteries provide DC current (not AC as in mains electricity). Only rechargeable cells are used in ecigs. Lithium ion cells are used because they have a higher voltage than regular rechargeable batteries (3.7 volts vs 1.5 volts) and because they have a higher charge density (the amount of energy that can be stored in proportion to their size and weight).

lithium ion cell issues: these cells cannot be regarded as intrinsically safe, in the way that regular 1.5 volt rechargeables are; they have stability issues. (There is an exception: Li-FePo4 cells are notably stable.) Their use must be subject to careful management: the physical conditions of use, the charging regime, and the discharge regime are all important for safety.
   As an example, large battery packs that use these cells (as in electric cars and aircraft) must have extremely comprehensive management systems, and ideally cryogenic cooling systems, because thermal runaway is a significant issue. The recent Boeing Dreamliner aircraft battery fires occurred because the lithium cell packs were poorly designed and poorly managed (it appears that the design of the cryogenic cooling system may have been defective). The nominal voltage is 3.7 volts – this means the average circuit working voltage. They can be charged up to 4.21 volts and discharged to 3.2 volts. Usage outside these parameters will damage the cell. Maximum cell service life is achieved by charging to 4.17 volts maximum and discharging to 3.4 volts mimimum.
   ‘Li-Poly’ cells (lithium polymer packs) are normally flat/square in format, and additionally have an impact damage issue that means they must not be used for any service where shock impact may be experienced. Some sub-types are demonstrated to catch fire immediately if severe impact is experienced, or while subsequently on charge.
   Unprotected Li-ion cells must not be used in series (‘stacked’) as this is shown to create a significant risk of thermal runaway and failure with flame and violent outgassing. Use of such an arrangement in a sealed device has significant risks for explosion. Since this is the regular format used in ultra-high-power LED torches (flashlights), serious failure events are common; an expert on these issues at the Candlepower forum estimated there is a ‘lithium cell incident’ for every 1,600 units sold. Regular lithium batteries, aka camera batteries, primary cells, ordinary batteries – must not be used in an e-cigarette under any circumstances. This is because they may be recharged by mistake, leading to known examples of serious battery failure events.
   Counterfeit batteries are a major problem in the e-cigarette world due to the wide scale of the issue. This problem is specific to APVs since the mini and mid-size devices have integral cells installed by the manufacturer of the device, who can source them correctly. Consumers, on the other hand, have little protection because it is almost impossible to verify the original source of the batteries they buy at retail. The problem is that the large-battery APV devices need safer-chemistry cells such as the Li-Mn / IMR type in order to operate safely; but such cells are expensive and therefore a target for counterfeiters, and may be of any type, beneath the fake label. As a specific example: AW Batteries is a known source of good-quality 18650 IMR cells, and only sell through authorised distributors, and such batteries are expensive at around $10 each. They can also be found offered for sale on the Alibaba website, a popular source for Asian wholesale supplies; AW state that all available from this source are counterfeit. This raises an important issue: since the fakes might be poor-quality IMR cells with a fake label or even reject-quality unprotected Li-ion cells stripped and re-labelled as AW IMR cells, there is a significant risk of violent failure in the high-demand service an APV may create; the dangers in this situation are clear.

mini e-cigarette: a regular or small-format e-cigarette, aka  ‘cig-alikes’,  ‘look alikes’, ‘looky-likies’, ‘stick ecigs’, and so on. Typical minis include the 510 and KR808 ranges. Minis are the smallest of the three classes of ecig (mini, mid-size, APV) and are designed to replicate a tobacco cigarette in size and shape. These cigarette clones were the 1st-generation models and are still the most popular in terms of market share (about 75% of the US market), since the majority of newcomers prefer a device that precisely replicates a tobacco cigarette in size, shape, and looks. However, the market has moved on, and far better performance is available from later (but larger) models. The performance of minis has not improved radically unlike that of all the other model types, because the battery size constrains any improvement. In contrast, the performance of other models has improved dramatically, and the 2nd-generation and 3rd-gen products are now dramatically superior. These more recent, larger models (such as the mid-size/eGo type or the APVs) provide a clear upgrade path, with performance gains of two to five times or so.

mid-size e-cigarette: the larger, 2nd-generation e-cigarette models that have about double the performance of minis. The original design was the eGo (by Janty), who did not patent the design, and now there are a multitude of choices (‘clones’) including the kGo, Riva, Tornado etc. These models are about the size of a fat cigar, and are the medium-size grouping within the three size groups (mini, mid-size, APV).
   The mid-size ecig is now the benchmark model, and all measurements of all metrics should employ a mid-size unit as against a mini, which is obsolete for any purpose except new-user introduction or use by occasional / social smokers. 92% of persons polled at a typical vapemeet had upgraded from a mini to a larger model.
   The physical size of the battery is critical to e-cigarette performance, since (a) a relatively high voltage is needed, (b) a very high current is required compared to the physical size of the cell (about 2 amps, and this is high for a small cell), and (c) the size of a battery dictates the time of usable performance. Larger ecigs perform far better than smaller ones, almost entirely due to the size of the battery.

mod: any modification of an e-cig or one of its parts (see APV, bonuts).

O-ring: a circular seal usually made from silicone or a synthetic rubber. O-rings are widely used in ecigs to provide a sliding fit with a good liquid and gas seal, especially in larger or custom models. Almost all driptips employ one (or two, in some cases).

penstyles: early large-format ecigs of around 150mm in length, resembling a pen in size and appearance, as they had a larger battery than the minis together with a step and wider diameter section at one end, resembling a pen. They came after the mini and super-mini, and were an early attempt at improving battery life and performance since the minis of the time had really poor performance. The heyday of the penstyle was 2009 – 2010, after which they died out as APVs and the eGo models (which started the explosion in mid-size clone devices) did the job far better.
   A typical model was the DSE801. Many penstyle ecigs were autos. All were of the 3-piece battery-atomiser-cartridge format, a poor arrangement in modern terms.
   It needs to be stated, in fairness, that the 801 atomiser itself was probably the best ever invented, from an engineering standpoint, as it was slightly larger and mechanically far stronger than other competing model series such as the 510 and 901. When used as a dripper atty on a 5v boxmod, the 801 atomiser represented the peak of performance in early 2010.
   Unfortunately the regular penstyle system suffered from the usual ills of the 3-piece ecig designs: leaking, short refill usage, and annoying glitches such as leakdown battery death on the auto models.
   The Ruyan V8 is an example of a penstyle still available now. It would be tempting to say that the world has moved on a long way since then; except that by re-modelling and re-marketing the devices as Shisha Pens, the circle has turned again. As an ecig, the penstyle is obsolete by many years, like all its contemporary rivals.

primer puff: a puff taken before the main usable puff when using a mini ecig. It is used because the tiny battery cannot heat the atomiser sufficiently to produce a usable result in a short time (i.e., the same time that a tobacco cigarette inhale lasts for); therefore, either an extra-long inhale of 6 or 8 seconds is used with a mini ecig, or a primer puff is taken (the vapor from the primer puff being discarded since it will have no usable nicotine content). However, auto battery mini ecigs sometimes cut out due to over-operation when used in a manner that delivers a satisfactory nicotine content, which will involve either a primer puff or an extra-long inhale in order to heat the atomiser sufficiently.

PV: personal vapouriser. A more accurate term than ‘e-cigarette’; though EV is better (electric or electronic vapouriser).

RBA, RTA, RDA: rebuildable atomiser, rebuildable tank atomiser, rebuildable dripper atomiser. These heads are generally made from stainless steel and employ a rebuildable coil and wick system, with a tank reservoir in the case of the RTA. Unlike most other ecig parts, an RBA is not a disposable item, which is part of its functionality: in theory an RBA might last for ever, needing only nichrome or kanthal resistance wire and stainless steel mesh or silica rope for rebuilding the coil and wick occasionally (these are widely available for other purposes). Combined with a generic battery holder body (APV), they are essentially an everlasting device that only needs common parts for occasional maintenance. Some are small and slim in format, others fairly substantial. The tank variants must be refilled from a bottle.
   The emergence of RBAs has caused a renaissance in the mechanical APV market (‘mechmods’), since only these devices can reliably handle the high current demanded by the super-low resistance coils popular with some RBA users (often below 1 ohm, and referred to as ‘sub-ohm’ coils). These devices are capable of producing huge amounts of vapour, which is part of the attraction for some vapers.

steampunk: a style of mechanical (usually) devices of the APV type that resemble the mechanical devices of the industrial revolution in their semi-crude machine-like appearance. One example might look like a torch/flashlight made from a copper steam engine boiler adorned with cogs from a large clock; another like a stainless steel hydraulic cylinder/piston assembly.

sub-ohm: sub-ohm vaping is the use of an RBA (qv) with an atomiser coil (or multi-coil group) of a resistance measuring below 1 ohm. These devices can produce a phenomenal amount of vapour, although it tends to be hotter and drier than with other devices.

vaping: using an e-cigarette, and thus inhalation of vapour not smoke.

vapour: the water-based mist that an e-cigarette produces. US spelling is ‘vapor’. Vapour consists predominantly of water (~66%), plus small amounts of PG, VG (both generally <4%), and nicotine (generally ~1%). Flavourings make up the remainder. Essentially, there are no concerns about any aspect of the ingredients except for flavourings. A more accurate term for ecig vapour is aerosol, qv.

WTA: ‘whole tobacco alkaloids’, a term used to refer to compounds additional to nicotine that may play a part in the effects produced by tobacco consumption: the other active alkaloids such as nornicotine, anabasine, anatabine, myosmine etc.
   For example, some people still experience significant, extended and unrelenting cravings after smoking cessation when using an e-cigarette with a strong refill. This means that, even when supplied with more than sufficient nicotine (enough to cause symptoms of over-consumption), and even when the nicotine is inhaled (to replicate the fast effects of smoking), and even when the physical routines of smoking are well-replicated (thus removing any question of the implication of physical or social mechanisms in any remaining craving), there is an additional and currently unexplained chemical dependency issue. For a significant proportion of these people, additional consumption of Snus or WTA-inclusive refill liquid is an effective solution. This appears to demonstrate that WTAs are implicated in the dependence profile for those persons, and that, for them, the chemical dependence profile is complex.
   Many quitters experience some cravings that gradually diminish over two weeks or so, even when supplied with correctly-performing 2nd-generation e-cigarette systems. Thus, it is found that the dependence on the WTAs / other cigarette smoke ingredients is surmountable by many who switch successfully to an ecig. A small percentage find their cravings persist even when supplied with sufficient nicotine and with WTAs, and this appears to indicate that there is dependence on other smoke ingredients.
   There are currently only two vendors of WTA ecig refills, both in the USA, but this number is expected to increase. The limiting factor is the cost, because it requires (a) a custom extraction process from tobacco leaves; (b) an expert chemist; (c) a fully-equipped laboratory to test for desired and undesired ingredients. WTA-inclusive e-cigarette refill liquid is effective but not cheap.

Wick: A narrow piece of string inside of many styles of attys that allows easier delivery of Juice to the heating element.