I'm not putting THAT in my mouth..they blow up!
Lets start off by talking about what an 18650 battery is exactly, The term "18650" is more of a classification of size for these types of batteries (meaning 18mm diameter, and 65mm height). The technical name for the type of battery is "Lithium Ion" and they are commonly used in many everyday items such as cordless power tools, laptops, and can even be used to store solar charge from a solar panel. Now the biggest issue with using 18650's in a vaporizer is that instead of coming in a battery pack, (much like a laptop battery) they come as individual cells to save room and make your vaporizer more compact, so instead of having a hard case around the battery to protect it you are left with only the soft heat wrap which can be damaged a lot easier leading up to the perfect storm for a short circuit which will be talked more about later.
How do they work?
Lithium Ion cells have a positive and a negative, The positive is a smaller circle on the top of the battery surrounded by an insulator, the negative of the battery is.. well pretty much everything else. The little insulator piece underneath the positive connection is what keeps the positive disconnected from the negative, this keeps from completing the circuit and firing off indefinitely. The reason for the heat wrap is to keep the exterior metal of the battery (which also acts as a negative) from contacting anything else ex. loose change, the insides of a "mech mod". It is always EXTREMELY IMPORTANT to make sure that the wrapping on your battery cell is always in tip top condition.
What happens if it short circuits?
One of two things can happen if your battery is damaged and it manages to make a connection. Both are scenarios in which the cell has made a connection with itself causing it to begin to backfire, build up pressure, and start heating up. "Venting" is the first thing that can happen and this is when pressure builds up slow enough that it causes the cell to "spring a leak", when this happens you will hear a hissing noise and should hastily make space between you and whatever your battery is in. Normally venting a battery is not too dangerous and when the battery has finished being "angry" you may dispose of it in a proper fashion. Now "Thermal Runaway" is what can happen if pressure in the cell builds up to fast for the cell to handle, normally causing those terrible headlines: "VAPE BLOWS UP IN POCKET" or "DON'T USE A VAPE OR YOU WILL EXPLODE". Although thermal runaway is extremely rare and virtually non-existent as long as you make sure you keep an eye on your battery wraps, I figure that it is still good to know what to lookout for. The build up to thermal runaway is the same as if a cell vents, you will first notice a lot of heat coming out of the battery (I mean A LOT) and that is the sign to get some space between you and the cell. Venting and Thermal runaway always leads back to user error (unless you bought counterfeit batteries that aren't what they really say they are) so always remember to check your batteries before use!
Final words
There are many, many more things that I could say about batteries, such as reputable sources to buy them, different brands, different types, and so much more but in the spirit of sticking to the complete basics I will have to save these topics for future posts. I greatly appreciate any feedback on this topic and if you have any information to add I would be more than happy to discuss it in the comments below!
As always I hope that you are all having a classy ass day and remember not to forget about spreading that Peace, Love, and all the Good Vibes!!
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