We've all seen the latest headlines involving e-cigarette explosions and users being rushed to the hospital with severe wounds; and because events like these have the tendency to produce mass panic and hysteria I believe it's a good time to talk about some general e-cigarette safety tips to shed some light on the subject.
The first and most important thing we need to understand is that electronic cigarettes, mods, personal vaporizers or whatever you decide to call them have been designed to be used only by responsible adults with at least basing understanding about the whole e-smoking process. Many of these devices come with manuals or warning cards, however not all people pay close attention to them and start using their very powerful mods and accessories based on their previous experience or they rely solely on intuition. ALWAYS read your device's manual before using it and NEVER ignore the warnings on the box or cards.
An electronic cigarette is a battery powered device that uses the energy to heat up a coil inside the atomizer and transform the e-liquid into nicotine infused vapor. Depending on the type of product, the battery can be either internal or sold separately and the atomizer can be a clearomizer tank, an RTA, or an RDA. But regardless of type, an e-cigarette is virtually a casing (tubular or box shaped) for the battery and the atomizer a casing for the coil that's connected to the battery (which may or may not have an e-liquid reservoir attached). So, when the user presses the firing button, this basic electric circuit closes and current from the battery goes through the coil, heating it up and transforming the e-liquid on the wicking material into vapor.
The next important thing that you need to understand is that e-cigarettes or mods fall in two distinct categories – regulated devices and unregulated devices. Regulated devices have built-in circuits or boards which – as the name says it – help regulate the current from the battery to keep a steady amount of vapor regardless of the charge and directly linked to the selected output power value. Regulated devices usually have displays and adjustment buttons, but they can even come in the shape of an eGo battery. These products have built in safety features like short circuit protection, over current protection, high voltage protection, low voltage protection and even temperature protection.
Unregulated devices on the other hand – also referred to as mechanical mods – are essentially empty casings for the batteries and they can be either tubular or box shaped. These are only fitted with positive and negative pins for the battery and they don't include any extra circuitry, chips or boards. Because they don't have any safety features, mechanical mods (or unregulated mods in general) are ONLY intended for advanced ecig users and people who are familiar with Ohm's Laws of electricity. Because the coil draws the current directly from the battery, knowing its resistance its crucial. Same goes for understanding the types of batteries and some basic notions about their ratings.
Mechanical mods (both tubular and box shaped) work with a few types of batteries – 18350, 18650, and 26650 models, with 18650 being the most popular. These batteries are manufactured by different companies and usually the cheapest ones need to be avoided.
Two specifications are characteristic to any 18650 battery (or any other type of battery) – the Capacity (1800mAh, 2200mAh, 2400mAh etc) and the Continuous Discharge Rate or Amp rating (20A, 25A, 30A etc). The Capacity is directly linked to how long should the battery last between charges and the Continuous Discharge Rate shows the maximum electrical current which the battery can provide continuously. When it comes to electronic cigarettes and vape mods, it's better to have a battery with a high Continuous Discharge Rate rather than with a bigger Capacity.
The batteries with high Continuous Discharge Rate are also called 'high drain' batteries and you should only buy them from top companies like: AW, LG, MNKE, Panasonic (Orbitronic), Samsung, Sony, and some Efest models.
NEVER make compromises when it comes to batteries for a mechanical (or unregulated) mod and keep away from shady sellers, clones and cheap alternatives.
Ohm's Law states that Amps = Voltage / Resistance, so this is why it's crucial to know your resistance, battery capacity and continuous discharge rate when using a mechanical mod. For instance if we have a 18650 battery rated for 2000mAh capacity and 20A continuous discharge rate (with a voltage of 4.2V when fully charged), and we measure the coil resistance to be 0.5 Ohms, then we have A = V/R = 4.2/0.5 => A = 8.4. Thus, the resistance needs 8.4A of current to heat up the coil, and since the battery has a continuous discharge rate of 20A, there would be no problem. For a lower resistance, of 0.25 Ohms, we would still be on the safe side because A = 4.2/0.25 = 16.8A, which is still < 20A. HOWEVER, if we were to use a 0.2 Ohm coil, things would get DANGEROUS because A = 4.2 / 0.2 = 21A, which is higher than what the battery can offer. This stresses the battery beyond its limits and could result in an explosion.
And because when it comes to building coils the difference between 0.25Ohms and 0.2 Ohms could be just an extra loop, a different wire gauge or a different loop diameter, it's CRUCIAL to correctly measure the resistance before mounting your atomizer on top of an unregulated mod. ALWAYS have an ohmmeter to test and always make sure your battery can handle the load. The main idea is BEGINNER + UNREGULATED MOD = DANGER so make sure you always use a regulated mod if you are not sure about your resistance and battery specs.
Most of the accidents presented on the news have been the result of inexperienced vapers misusing mechanical mods and going beyond the limits of their batteries, so I highly recommend only regulated mods to all beginners and intermediate vapers before learning about Ohm's Laws, buying an ohmmeter and making the transition towards a mechanical.
But regulated mods aren't also 100% safe, especially if you use them with cheap batteries or push the electronics to the limit. Even though these devices come with built-in fuses and safety features, one can never be too sure as to use them close to their intended maximum or minimum. If, for instance, you read in the manual that your mod can fire as low as 0.2 Ohms, never use it with those 0.2 Ohms, because you're entering a grey area, where the build quality of the internal or purchased battery starts to become critical. And with millions of batteries sold worldwide, statistics tells us there are a couple of items out there that hide small manufacturing defects that could become hazardous when stressed to the limit.
And even though some manufacturers advice you to use their products while charging, I'm strongly against this practice, because you're putting a lot of unnecessary stress on both the battery and the internal components of the device.
It's always better to treat any electronic product with respect rather than with the 'I know better' attitude and be sorry afterwards.