The need for portability and long use has pushed electronic cigarette manufacturers to look for better ways to power the device. There are many different implementations as can be seen in the current models on the market. However, the use of 3.7V 18650 batteries is still the most popular. This is a small cylindrical rechargeable piece that features lithium-ion technology inside. Its size and shape make it ideal for placement inside e-cigs or at least their pen-type variety. They could be charged right inside the device if there is a circuitry for it but it is more common to take out the battery and place it in a separate charger.
What’s in a Name?
The masses are more familiar with lettered names such as those of alkaline batteries with sizes AA, AAA, D, and E or the button cell batteries like CR2032 for motherboards. The five-digit name might strike people as odd if they have not encountered this kind before. The first two digits are an approximation of the diameter as measured in millimeters. Meanwhile, the last three digits are an approximation of the height of the unit as measured in tenths of millimeters. The 18650s, therefore, have a diameter of 18mm (actually 18.6mm) and a height of 65 mm (actually 65.2mm). Some are a bit longer because of built-in protection circuits.
Lithium batteries have been under development since the 1970s but it wasn’t until the 1990s when the first commercial Li-ion batteries were produced. The technology quickly grew in prominence and usage with the majority of portable devices being powered by it today. Its appeal lies in its high energy density which means that bigger capacities can be made in smaller packages. Given the obsession with thinner, smaller, and lighter electronics, this is a crucial characteristic. It is also not as affected by memory effect compared to other battery chemistries. Self-discharge is low so it retains energy for a longer period when idle.
Things of Note
It should be noted that the quality can differ greatly between brands. Consumers must be careful when making a purchase as the cheaper ones might actually be dangerous. They might heat up quickly or even explode due to short circuits. Stick to the well-known brands and get them from trusted sources to ensure that they are genuine. Remember that the capacity can range from 1500mAh to 3600mAh. Look for the Best 18650 Batteries – reviews for 2018 to find out more about your options.