A mod is only as useful as the batteries inside it. When cells are old and no longer hold their charge, you end up carrying spares, turning the wattage down to stretch the power, or staring at a “low voltage/battery” message. This how-to covers charging, the handling mistakes to avoid, how long batteries last and the signs that a set is due for replacement.
Charging: port or external charger
Every vape device has a micro-USB port somewhere, whether on the front, the side or the bottom, and it is there so you can charge the batteries without removing them. Many vapers have become unhappy with that method and switched to an external charger. Our writer prefers one as well, for three reasons.
- You see each cell individually. The charger shows the level of every battery as it fills. When two cells show different percentages, you know one of them is holding less charge than its partner.
- The device stays in use. Our writer’s mod takes two 18650 batteries. When that pair runs flat it goes into the charger, a freshly charged pair goes into the mod, and vaping continues.
- It handles more than one battery type. Most external chargers accept 18650 batteries, 22500 batteries, ordinary rechargeables (AA, AAA, C and so on) and other cells designed for recharging. That is a convenience more than a necessity.
Seven handling rules
Vape batteries are delicate. Inspect them often for damage and wear, and follow these rules.
- Load them the right way round. Each cell has a positive end and a negative end. Our writer knows a vaper who inserted them incorrectly; the cells swelled and came close to exploding inside the device.
- Do not drop them. A fall can dent a cell or make it swell. A new battery is smooth, sleek and evenly shaped. Throw away any that look dented, lumpy or swollen.
- Watch the vinyl wrap. On the purple Imren 18650 cells our writer uses (spelled “Imran” in the original post), the wrap starts tearing at the edges, mostly near the top and bottom where fingers touch it most. A tear can stop the cell charging properly or stop the device switching on.
- Do not patch a torn wrap with electrical tape. It looks like a quick fix, but it encourages you to keep using damaged cells and delay buying safe new ones.
- Never pair an old cell with a new one. A new battery holds its charge far longer. The device draws from both, so the old cell can give out while the new one still has half its charge, leaving you stuck.
- Buy new, unopened batteries only. However good a used deal looks, you cannot tell how hard the previous owner ran them. If they fail, they could damage your device and hurt you or other people.
- Use only cells intended for your device. Some mods ship with adapters that let them take two battery sizes, 18650 being one of them. Rechargeable AA batteries are not a substitute, however similar they look, and using them can seriously harm both you and the device.
Signs your batteries are finished
There is no fixed lifespan for a vape battery. It depends on use: a device that runs all day puts its cells through many more drain-and-recharge cycles. As a rule of thumb, think about a new set at least once a year, or sooner if you notice the current ones no longer hold a charge the way they did.
Two symptoms are worth knowing.
- Short run time. The clearest sign is a battery that lasts only a few hours. If you need to recharge after just 3-4 hours of use, the cells are worn.
- Odd readings on the screen. The mod may show “wattage too low”, or flash a low battery indicator that then jumps back up to a much higher level. That pattern means the device is asking for more power than the battery can deliver. Turning the wattage down may help for a while, but it only works around the problem until the level really is too low for the mod to fire.
What comes next
This article was written for the batteries you already own. The follow-up looks at buying new ones: specific battery types, how to read wattages and which brands our writer prefers. If you have a battery question that was not covered here, get in touch with us by email, on social media or by phone.