The batteries we use in our devices are powerful cells capable of providing high output. With this comes the potential for damage and injury, and considerable amounts of it, if not used properly. So, below are some facts, tips and pointers about using high drain/high amp batteries in your personal vaporizers.
Not all batteries are equal
Just because two batteries are the same physical size and shape, does not mean they have the same capabilities. Ensure you know what the make, manufacturer, amperage and mAh are of any battery you use before you use it, and make sure you use the appropriate batteries for the devices and coils you run.
Batteries get married too
You may have heard the term "married pair" in reference to batteries in the past. What this means is that these batteries have only been used together in devices from the first time they were put into use. And yes, with the popularity of triple battery devices as of recent, you do "marry" a 3 battery set. The reason why people do this, and why its highly recommended, is because a set of batteries of the same make and model, if used together and charged together, will have similar enough charge and discharge rates as to prevent them from being unbalanced. An unbalanced set is a set with a large difference in charge (eg: Battery A is at 4V while Battery B is at 3.4V), and/or recharge rates (eg: Battery A charges to 4.2V in half the time Battery B takes).
If batteries are unbalanced, there is the potential of battery failure. Many devices don't have the ability to check each battery for it's charge, and displays an average of what both cells provide. This means while your device may tell you that you're battery life is 30%, one of your batteries could be discharged beyond its safe discharge point, and the other is still well above it. A battery discharged below its safe discharge point may not be able to recharge or may never hold a full charge like it used to. We recommend not bringing your batteries below 3.2V.
In normal usage, there will be differences in charges that you'll notice if you use an appropriate battery charger that provides a display of current charge, or a multimeter. A difference of 0.1V isn't a concern, but larger than that could be a sign that your device is pulling one battery harder than the other(s), or that one battery is starting to show signs of use and "age" faster than the other.
Check batteries for physical signs of wear
When handing your batteries, make sure to check them for physical damage. Dented, corroded, swollen or misshaped batteries should not be used and disposed of properly at an eco center or a battery recycling facility. Ones with torn wraps or insulator rings can be rewrapped and the insulator ring replaced, but do not use them until you can do so. The wrap on a battery is more than a place for the manufacturer to write the specs - it prevents the battery from shorting out. A battery that shorts out can potentially leak, vent, or explode.
Know what you need to run what you vape
A general rule of thumb is that the lower the resistance of the coil, the higher the amperage you'll need to run it safely. Calculate the amperage you'll need by using one of the many online calculators (such as the one found here) before firing that coil, and then make sure your battery or batteries can handle it. And in the case of multiple battery devices, ensure your calculations take into consideration if the device is running those batteries in series, or parallel.
For example, with a single battery device, running a 0.5Ω with a fresh battery (4.2V) would result in it requiring 8.4A in order to run safely. And while that may sound easy, as many of the batteries sold today are high amp, there still exists low amp batteries that are the same size as what we use.
In a device that's wired in series, things are different. You will still end up with the fresh battery voltage of 4.2V, but because you're pulling equally from two batteries, you're doubling your amperage. (The batteries are put into a series device in the same orientation, such as positive end up for both batteries. But this isn't a hard and fast rule - always check with the user manual or the manufacturer to be sure.)
In a device that is wired in parallel, thing can easily border on dangerous if you don't calculate your amperage requirements. In a parallel build, you voltage doubles, but the amperage output of your batteries remain unchanged. As voltage increases, amperage increases. The 0.5Ω coil that would require 8.4A to operate on fresh batteries in a single or series device would require 16.8A.
And lastly, never run at the max a battery can provide. For instance, with the last example, one may think that 20A batteries would be fine. But coils can vary +/- 0.2Ω in use, and 0.3Ω on that same device would require 28A, which is more than the battery is rated for. Give yourself some wiggle room.
Carry batteries properly
I can't tell you how many times I've seen or heard of people carrying spare batteries loose in their pocket or purse, sometimes along with their keys, spare change, or a number of other metal or conductive objects.
This is a big no-no, unless of course you like having your pants light on fire cause your battery shorted out.
Batteries should always be carried in something that will prevent it from becoming damaged and from shorting out against anything, including other batteries. Appropriate carrying cases are available for single batteries and multiples. Get some and save yourself from becoming a statistic.
Be careful with which way your batteries go into your devices
While a number of the devices on the market today have reverse battery protection, there are many that don't. If you happen to put your batteries in backwards, the best case scenario is that nothing happens, but this isn't what happens normally.
If you put your batteries in backwards, you could end up shorting, either causing your batteries, your device, or both, to be damaged, many times beyond repair, sometimes with catastrophic results. Be mindful of what you're doing when you're putting batteries into anything - device, chargers, etc. And don't trust or assume that it has reverse battery protection. Even those sorts of fail safes can fail.
Protect your batteries from temperature changes
Batteries, like people, prefer comfortable temperatures. Cold temps can reduce the life of your battery. High temps can cause battery failure. So never store your batteries in your car (particularly in summer or winter), near heat registers or heat sources, or in your fridge (I've actually seen people recommend this).
It may sound like a lot to keep in mind, and potentially scary outcomes if forgotten, but safety is not something to take lightly. Knowing how to store, charge, use and transport your batteries will save a lot of money and pain. All battery usage is at your own risk, so it's imperative you know these things. Vape safe!