You picked a great place to ask. We have some real battery experts here, including a guy called Mooch who not only explains all sorts of battery-related information on
his blog but also tests the batteries we tend to use for vaping.
About the voltage, all the 18650s we usually use for vaping have a nominal voltage of 3.6 or 3.7. A battery's voltage goes up when it's charged and down as it's discharged, so it actually varies from 4.2 volts when fully charged to about 3.2, which is where most mods will give you a low battery warning.
On to finding a suitable battery:
I'll start out with a few key points:
- 18650s aren't like AAs where they're all pretty much the same. One model of 18650 might work well for vaping, while another will have completely different specifications and not be suitable at all.
- 18650s are often counterfeited, so where you buy the battery can be as important as which battery you buy. Even reliable vendors can be taken in, but they really reduce the risk by building better supply chains and by spot-checking the performance of the batteries they source.
- You also can't trust the specifications of many of the batteries that are available. The best way to deal with this issue is to stick to major/reliable brands (Sony/Murata, LG, Samsung, Sanyo/Panasonic, and Molicel)
What you need to know to pick a battery:
18650s have two key ratings, CDR (continuous discharge rating) and capacity. CDR, in amps, tells you what wattage you can vape at. Capacity, in mAh, gives a rough comparison of how long different batteries will go between charges. The higher the capacity, the longer it will last.
CDR is the most important. The rule of thumb is that your wattage can go up to three times the CDR per battery. The cell you listed has a 20A CDR. That means you can vape at up to 60 watts on a one battery mod or 120 watts on a two battery mod. However, if you're getting close to the limit, you'll usually get better performance from a battery with a higher CDR.
There are many battery models from the manufacturers I listed above that are suitable for vaping (and many that aren't), but the easiest way to pick one is to let someone else do the work. Mooch's list of recommended batteries is a great place to start. So, to pick a battery:
- Decide what wattage you want to vape at, and figure out your minimum CDR.
- Go to Mooch's Regulated Mod Recommended Batteries Table and see which 18650s there have a CDR that works for you.
- Check the blue row near the bottom of Mooch's table for a list of reliable vendors, and buy your batteries from one of them.
Other notes:
- Batteries can be charged in the mod or with an external charger. Mooch and others recommend the external charger. Chargers can be purchased from the battery vendors on Mooch's chart, and generally reliable manufacturers include Xtar, Nitecore and Efest's LUC line (be careful of other lines by Efest - at least one's been found to have problems).
- I suggest picking up a few battery wraps when you get your batteries. The wrap is the plastic sleeve that covers the battery. It's easily damaged but essential for safety. The good news is that replacing it takes a 10-cent battery wrap, a hair dryer, and about 4 minutes of your time. There are lots of helpful videos on Youtube. Also, check your wraps for damage whenever you take them out to charge them.
- Never carry a battery loose. If it's not in your mod or being charged, it should be in a battery case (available for a couple dollars wherever you bought the battery).
- Never use a battery that's dented or otherwise damaged.
Finally, here are some resources for more information:
Good luck!
