Vape Batteries

How to Choose a Vape Battery

Many vape mods run on removable cells that are bought separately, and the cell you pick affects how long the mod lasts and how safely it runs at your chosen power. The Uwell Nunchaku 80W RDA Kit is a typical example: it takes one 18650, and the battery isn’t included. Three things matter when choosing a replacement: size, capacity and current rating.

Battery Sizes Explained

The number on a cell is its size. An 18650 is 18mm wide and 65mm long, and a 21700 is 21mm by 70mm. They aren’t interchangeable, so your mod’s manual or the battery door will tell you which it takes. Here’s what we stock in each size:

• 18650: the most common size in single and dual-battery mods. See the Sinowatt 25SP 2500mAh 18650 Battery, Sinowatt 30SP 3000mAh 18650 Battery and Vapcell K25 18650 Battery.
• 21700: a larger cell with room for more capacity. See the Vapcell P42A 21700 45A 4200mAh Battery and Molicel P30A 21700 Battery.
• 18350: a compact cell for small tube mods at low power. See the Efest IMR 18350 Battery, rated at 700mAh and 7A continuous.

Capacity and Current

Capacity, measured in mAh, tells you roughly how long a cell lasts between charges. Current, measured in amps, is how much it can safely deliver at once. Higher-power vaping and lower-resistance coils ask for more current, so a cell with plenty of capacity isn’t automatically the right one for a high-power mod. Look at the continuous rating rather than the pulse or maximum figure. The Vapcell K25, for example, is rated at 20A continuous and 35A maximum, and 20A is the number to work from.

Looking After Your Batteries

• Check the wrap and replace or re-wrap any cell with a tear or nick, because a damaged wrap can cause a short.
• Carry spare cells in a proper case and never loose in a pocket with keys or coins.
• In a dual-battery mod, use a matched pair of the same make and age, and charge them together.
• Use a dedicated charger rather than relying on your mod’s USB port where you can. Several of our vape battery chargers show the voltage on screen.

If you build your own coils, take extra care. Very low-resistance builds can draw more current than a cell is rated for, so check your numbers before you fire a new build.

Our cells come from Molicel, Vapcell, Sinowatt and Efest, and each brand page shows everything we carry from that maker.

Need a Hand?

If you’re not sure which cell your device takes, bring it into one of our vape shops in Southampton. We can check the size and talk through your options. You can also order online for UK delivery.

Frequently Asked Questions

Which battery does my vape mod need?

Your mod’s manual or battery door shows the size, which is usually 18650, 21700 or 18350. These sizes aren’t interchangeable, so match the size exactly.

What is the difference between mAh and amps on a vape battery?

mAh is capacity, which tells you roughly how long a cell lasts between charges. Amps are how much current it can safely deliver, so work from the continuous rating rather than the pulse or maximum figure.

Can I mix different batteries in a dual-battery mod?

No. Use a matched pair of the same make and age, and charge them together.