Vaping Safely: What Are Mod Batteries

With so much media exposure about mods and e-cigarettes blowing up recently, we at have decided to do our part to inform the public on battery safety. These stories are generally regarding mod batteries, AKA Lithium 18650’s, and so we believe this is an important place to start for anyone interested in vaping on a mod. Hopefully by the end of reading this you will be more knowledgeable and comfortable vaping on your mod, and as a community we can stay safe and keep batteries from exploding.

What do the numbers mean?

The battery numbers are a measurement. An 18350 is 18mm in diameter and 35mm long. The 0 at the end means it is a round battery.

18350: 18mmx35mm    18500:18mmx50mm     18650:18mmx65mm

What do the letters mean?

The first letter indicates the basic chemical makeup of the battery. The second and most important letter indicates the material. “I” means that it is a Lithium Ion class battery. “C” indicates the material as cobalt; “M” indicates manganese; “N” indicates nickel. The “R” just means rechargeable.

The “AW” on some batteries is initials for Andrew Wan, who owns a China-based company which purchases large quantities of batteries from the big boys (Samsung, Panasonic, etc.) and performs quality tests on each one.

ICR batteries (Li-Ion/Cobalt/Rechargeable) can handle most atomizers we buy over the counter today. They are known for their higher capacities and are suited for the average vaper’s device, but they are not at all well suited for use in advanced devices. These batteries are best used in applications with a current draw of less than 3A. ICR batteries do need to be protected either built in to the battery or with a Vape Safe fuse.

IMR batteries (Li-Ion/Manganese/Rechargeable) are modders’ preferred battery type. They have a “safer” basic chemistry than ICR batteries as they can sustain higher internal temperatures before becoming unstable. They will be overcharged by old-technology chargers and may burst. Overcharging (>4.25 volts) or discharging below 3 volts will shorten the service life. If you run them below the minimum discharge voltage the cell can be damaged. There is no ‘trip out’ as with a protected Li-Ion battery.

Li-FePo4 batteries are lithium ferrous phosphate and are a newer technology that is quiet pricey in comparison. Most have a working voltage much lower than the Li-Ion equivalent and they cannot be used with Li-Ion chargers.

What is battery duty cycle?

Battery duty cycle refers to the approximate number of recharges it can be “cycled” through before the battery will no longer hold a charge. Duty cycles can vary between 150 and 500 depending on the core battery composition and care of the battery.

How do you properly charge mod batteries?

A Li-Ion battery has no “battery memory” or “charge memory” so it can be charged at any point of the discharge cycle with no ill-effects. It does not need a long first charge or a “conditioning” first use, full discharge then a full charge. They are fully charged at 4.2v and best recharged at 3.4v. They must not be discharged below 3v or they will be damaged. It is advisable to recharge them before they reach full discharge, as this extends their service life. It may be a good idea to rest batteries after charging.

Protected vs. Unprotected

There is a common misnomer in the vaping community that a protected battery is safer to use than an unprotected battery. There is a belief that a protected battery will prevent you from over-drawing your battery and causing it to vent gas or even explode. A battery labeled as “protected” does not always prevent you from applying a higher current draw than it is capable of handling. The protection circuits in batteries vary from manufacturer to manufacturer but primarily prevent you from over-discharging or over-charging the battery. The” protection” moniker is not all-inclusive either. Some will provide just over-discharge protection, others have over-charge protection and in some batteries over-current protection. The term “unprotected” is vague and often misunderstood. It can mean a “safer chemistry IMR or hybrid” that does not use a protection circuit or an “unprotected ICR battery”. Unprotected ICR batteries should NEVER be used in a mod. They are only suitable for less demanding applications like flashlights. All Li-Ion batteries have what is called a PTC or positive temperature coefficient circuit. This is built into the battery just above the positive terminal and is present regardless of any “protected” labels. The PTC is designed to raise the resistance of the battery as the temperature of it rises. The theory behind PTC is that as the resistance goes up, the current draw from the battery goes down-Ohm’s law. This helps prevent most accidents from happening but should not be relied on.

What are inline fuses?

Inline fuses are small disk-shaped components which you place inside your mod below the negative terminal on your battery. An inline fuse, commonly rated at 7amps, will prevent you from accidentally pulling too much current from your battery either from device failure or low atomizer resistance. If you are using a mechanical mod it is suggested that you use these!

By: Ashleigh Spaulding