High vs. Low Resistance Atomizers and Cartomizers
The term “resistance” as it applies to atomizers and cartomizers has to be one of the more confusing aspects of electronic cigarettes. If you buy the wrong type of attachment for your e-cigarette, you could experience disappointing performance, or worse yet, risk damaging your e-cigarette.
Atomizer Resistance Explained
To make the correct decision, you must first understand that “resistance” doesn’t refer to the vapor production of an atomizer or cartomizer; it refers to the amount of power that it allows to pass through. Thus, the atomizer or cartomizer takes the input voltage from the e-cigarette mod or battery, resists some of it and delivers a final power level that you can measure in watts. Because a high-resistance atomizer resists more of the current, it delivers less vapor than a low-resistance atomizer if everything else is equal.
To make the matter even more confusing, some e-cigarette vendors refer to high-resistance atomizers as high-voltage atomizers as if it’s the atomizers themselves that generate the power. This refers to the fact that these atomizers should be used with e-cigarettes that produce more than 3.7 volts of power, but it’s quite confusing to newbies. Thankfully, the practice seems to be disappearing.
If you take one bit of information away from this article about high- vs. low-resistance atomizers, it’s this: if you have a variable-voltage e-cigarette, buy a high-resistance atomizer or cartomizer and adjust the voltage of the e-cigarette to suit your taste. If you have a single-voltage e-cigarette, adjust the atomizer or cartomizer resistance to suit your taste.
All common e-cigarette batteries are 3.7 volts and most include atomizers or cartomizers with a resistance of 2.5 ohms. I like to refer to this value as “standard resistance.” With a standard resistance 2.5 ohm atomizer or cartomizer, the output power is 5.476 watts. This is roughly the power level you can expect from all popular e-cigarette brands. By lowering the resistance to 1.5 ohms, however, you can get more power out of a 3.7 volt battery because less of the current is resisted. The output power in this scenario is 9.12 watts. As long as you have a battery large enough to handle the increased load, a low-resistance atomizer greatly increases the vapor production and satisfaction derived from using an e-cigarette.
However, low-resistance atomizers cannot be taken past 4.0-4.5 volts on the Lavatube and most other variable-voltage e-cigarettes without triggering the over-current protection, which knocks the voltage down to 3.7 volts. At 4.0 volts, the Lavatube produces 10.66 watts of power. This is more than what you would get with a standard e-cig battery and atomizer, but still less than the maximum performance the Lavatube is capable of. In addition, you should avoid using a low-resistance atomizer on any cigarette-shaped e-cigarette battery unless the manufacturer says it’s supported. Small e-cigarette batteries generally can’t handle the load caused by low-resistance atomizers.
A high-resistance atomizer or cartomizer — usually classified as any attachment with a resistance of 3.0 ohms or higher — resists more of the input current, allowing you to use your e-cigarette at high voltages without fear of causing damage. Using a high-resistance attachment, you can operate a device such as the Lavatube at any voltage and experience the full range of the e-cigarette’s power.
If vapor production is ultimately all about watts, you might ask yourself why you couldn’t simply use a low-resistance atomizer and lower the voltage to conserve the battery life of your e-cigarette. The answer lies in the number of amps generated; using Ohm’s law, we arrive at the two scenarios below:
- A 3.0 ohm atomizer at 6.0 volts generates 12.0 watts of vapor at 2.0 amps.
- A 1.5 ohm atomizer at 4.24 volts generates 12.0 watts of vapor at 2.82 amps.
With most e-cigarettes, a load of 2.82 amps exceeds the capabilities of the hardware. This can cause the battery to die early and stop holding a charge. It could also cause the heating element in the atomizer or cartomizer to burn out. For this reason, a high-resistance atomizer or cartomizer is generally the best attachment to choose if you intend to use your e-cigarette at different voltages. However, a high-resistance attachment isn’t the best choice if your e-cigarette only operates at one voltage because the vapor production may be lower than you’d like.