E-cigarette Batteries: Vaping for journalists, Part 1

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e-cigarette battery explosion

E-cigarette Batteries: Vaping for journalists, Part 1

Vaping advocates have known for a couple of years now that the standard of media reporting on e-cigarettes is truly dire. Personally I hoped that when Public Health England said last year that scaremongering about tiny amounts of chemicals was frightening people back to smoking there would be a sudden improvement in quality. After all, surely the most in-depth study yet would carry some weight with the media?

No, apparently not. If anything reporting has got worse since then, and I didn’t think that was even possible. So the problem isn’t that journalists can’t find any accurate and reliable sources; it’s that they ignore them and listen to fanatics instead. In short it’s down to bad journalism. Of course not all journalists are bad, and we’ve seen a couple of excellent articles recently, but most of them are pretty awful. Sarah Knapton at the Daily Telegraph is the worst. But then Jasper Hamill at the Mirror is the worst too. Dozens more are almost as bad.

Anyway, just on the off chance that these hacks are actually capable of learning, I thought I’d put together a series of short guides on how to at least avoid looking like a complete idiot. Here is the first.

There is no such thing as an e-cigarette battery

The latest crop of scare stories seems to focus on people who’ve blown themselves up or set themselves on fire with “e-cigarette batteries”. Unlike clouds of formaldehyde and Stan Glantz’s mythical ultrafine particles there’s actually a real hazard here, and some people have managed to injure themselves quite badly with the batteries in their vape gear. But before I go into any more detail, please read the section title again:

There is no such thing as an e-cigarette battery.

E-cigarettes need quite a lot of power, and the only way to store that without carrying a battery pack as big as your head is to use rechargeable lithium-based batteries. Most of the time that means lithium ion batteries, but some devices use lithium polymer ones instead. Lithium batteries have revolutionised portable electronics because, compared to other types, they can store a huge amount of energy. That’s why they’re used in practically everything. Your phone, iPod, laptop and tablet all run on lithium batteries. So do electric cars.

Now, when someone designs a battery-powered device they don’t bother designing a new battery as well. Instead they use a standard model, and fit that into their design. Most TV remotes use AA or AAA cells, for example, and e-cigs are exactly the same. Most of them use standard cylindrical batteries such as 18650 or 18350 sizes. Others have built-in batteries – but if you take one apart you’ll find that, in fact, they use standard sizes too. Popular box mods like the iStick have one or two 18650s hidden away inside; eGo and cigalike devices use smaller, but still standard, batteries.

So there’s no such thing as an e-cigarette battery, just like there’s no such thing as a TV remote control battery, a fire alarm battery or a mobile phone battery. There are just plain old batteries, which can be used to power anything you want to pack enough of them into. If you open up the battery for your laptop what you’ll find inside is eight to twelve 18650s wired together – standard units again. Old-style removable phone batteries are just the same – plastic boxes with one or more standard lithium ion cells inside. Except don’t take battery packs apart to look inside, because it’s dangerous and they might explode.

Focus on batteries, not on vaping

There is no specific problem with e-cig batteries. The problem, such as it is, is with lithium batteries in general. Quite simply, they contain so much energy that if you don’t handle them safely it can escape suddenly – and, as energy tends to do when it escapes, it converts itself to heat.

The energy stored inside a lithium battery can convert itself to a lot of heat. If you have an electric immersion heater at home it probably draws a current of about 15 to 20 amps, and that can produce all the hot water your house needs. The three VTC4 batteries in the mod I’m using right now can each deliver a constant current of 30 amps. They can’t do that for very long of course, because they can only draw on their stored energy while your immersion heater is wired to the mains, but if you make a mistake it doesn’t take long for things to get very hot indeed. The worst-case mistake you can make with a high power battery is to short-circuit it.

A short circuit is where the positive and negative terminals of the battery are connected by a conductor that isn’t actually using the electricity, but just letting it flow through. Essentially you’re taking energy out one end and feeding it back in the other. Batteries don’t like this, and if you short one it will rapidly overheat. Very rapidly – in a matter of seconds. When it gets hot enough to boil the electrolyte liquid inside, the casing will burst; the electrolyte – and anything it touches – will probably catch fire.

Now, here’s where it gets interesting. Any battery has a positive and a negative terminal. On a cylindrical one like an 18650 or the familiar AA we think of the positive terminal as the nipple or flat contact plate at one end, and the negative as the bare metal surface at the other. This, however, isn’t quite accurate. The whole metal case of the battery is the negative terminal, with the positive surrounded by an insulator and inserted into the open end. The plastic sleeve that covers most of the case isn’t just there to make the maker’s logo look nice; it’s also an insulator. If that sleeve is cut or torn it becomes very easy to accidentally create a short circuit.

If you read past the headlines of incidents like this one, or this one, or this dramatic video, you’ll find that, despite the hysteria, no electronic cigarette was actually involved. What really happened was the victim was carrying a spare battery, loose, in either a pocket or a bag. This is frankly insane. We carry all sorts of things in pockets and bags, and many of them – coins or keys, for example – are made of metal. Stuff a high-powered battery in there too and a short circuit, followed by an explosion and fire, is just a matter of time. Even if there’s no metal in there with it, what happens if it rains and your trousers get wet? Water’s a conductor too, and that can cause a short.

Hybrid Hellfires

There’s another easy way to short a battery, and that’s by using a modern tank atomiser hybrid-style on a mechanical mod. Hybrids don’t have a separate contact between the battery and the atomiser; they depend on having the atomiser’s insulated centre pin protruding enough to contact the battery’s positive terminal, while the threaded negative that surrounds it is in contact with the mod’s metal case. The case, in turn, completes the circuit to the battery’s negative terminal. But most modern tanks don’t have a protruding centre pin; it’s flush, and designed to work with the spring-loaded pin on a regulated mod. Screw that down through your hybrid adapter onto the top of the battery and there’s a good chance both the pin and the threads will be touching the terminal. If they are, as soon as you press the fire button the current from the positive terminal will take the path of least resistance – skipping the atomiser, through the case and straight into the negative terminal. An instant short circuit.

Every case I’ve read about where a removable battery exploded either involved a hybrid device or the battery was being carried loose. Every case where a built-in battery went bang happened while it was being charged.

Of course most people will never short-circuit a lithium battery. They’re actually pretty safe. After all there are literally billions of them in daily use, and every day only a handful explode or catch fire without having been abused first. If you handle them sensibly the chances of an accident are negligible. But if you don’t handle them sensibly then you’re probably going to get hurt. Unfortunately lots of people buy them without knowing what the potential hazards are. You may argue that vendors have a duty to teach customers about battery safety, or you might feel that people should have enough sense of personal responsibility to educate themselves, but it comes to the same thing: Ninety-nine times out of a hundred, when a battery explodes it’s because someone did something they shouldn’t have. The hundredth time it’s usually caused by a minor flaw in the battery that suddenly causes a failure. What it’s never caused by is the fact the battery was used in an e-cigarette, instead of a torch or Rampant Rabbit.

So stop saying “e-cigarette battery”. You’re blaming the wrong thing.