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ZDNET’s key takeaways
It’s rare for a rechargeable battery to cause problems for the user.
Some 1,500 fires and 5,000 overheating incidents are attributed to rechargeable batteries yearly.
Don’t use any gadget that’s damaged or showing signs of overheating.
Rechargeable batteries are everywhere.
Stop what you’re doing and think about all the things in your life right now that contain a rechargeable battery — the laptops, smartphones, tablets, power banks, smart doorbells, and surveillance cameras. And don’t forget to count your wearables: smartwatches, earbuds, and smart rings all contain rechargeable batteries.
Then there are the batteries that we put to our mouths and suck on — the ones inside e-cigarettes and vapes.
Also: I tested a solid-state portable battery for a week – now lithium-ion feels outdated
And don’t forget that portable power station you have in the garage. That thing is literally a box filled with rechargeable batteries.
I’m betting that you have quite a few.
Right now, I have about a half a dozen within arm’s reach, and a lot more that live at my home, the office, or the car. And I’ve probably forgotten about that old smartphone in the back of a drawer, or the old — possibly recalled — power bank in my backpack.
For the most part, rechargeable battery-powered devices are incredibly well-behaved. It’s a good thing, really, because most of us are happy to go to sleep with a charging smartphone not far from our head each night, and cram ourselves onto an aircraft and spend many hours at 40,000 feet surrounded by hundreds of different devices — all of varying quality and state of repair — containing a rechargeable battery.
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But things can — and do — go wrong.
Just how dangerous are rechargeable batteries?
I’ve pulled up data from a few sources, and it seems that rechargeable batteries are responsible for approximately 1,500 house fires and some 5,000 “overheating incidents” each year. E-cigarettes also cause hundreds of injuries every year, most of which, thankfully, aren’t severe or life-changing.
And every year, a story makes the news about a smartphone or wearable battery misbehaving. Fortunately, most people walk away from such incidents with limbs attached and eyes working. However, that doesn’t change the fact that it could have been much worse, and that we should be vigilant and know what to do if we come across a battery that’s gone bad.
Damaging a battery — even an ultra-safe solid-state battery — is not a good idea.
Adrian Kingsley-Hughes/ZDNET
A modern rechargeable battery contains a lot of power in a very small space. Most of the time, batteries do what they are supposed to do — release that energy slowly and in a controlled fashion. But if anything ever causes the battery to release that energy suddenly, that’s when there is a risk of explosion and fire.
As someone who has witnessed several battery fires (some deliberate, others unexpected), I have a healthy respect for how much energy we carry around in our pockets.
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Make no mistake, a faulty lithium-ion battery is incredibly dangerous, and it can explode. And when I say explode, I don’t mean the tiny pop of a party popper (although some do go off in exactly that way). An angry battery pack can go off with a heavy-duty bang, and it has enough energy to shatter the device wrapped around it, creating a shower of shrapnel.
But a bang and the resulting shrapnel isn’t all you need to worry about, because chances are that you will also find yourself in the middle of a spray of molten lithium metal and a thick, acrid cloud of choking toxic fumes.
And this enthusiastic chemical reaction is probably not going to happen when you’re outdoors, surrounded by fresh air, away from combustible materials, and when you have a fire extinguisher close to hand. Oh no, it’s going to happen when you least expect it. Maybe when the device is all snugged up in your pocket, or when it’s on charge in the car and you’re zipping down the highway at 65 mph.
Or when it’s right next to your head on your nightstand — when you’re fast asleep.
Why do batteries catch fire?
Again, thankfully, explosions and fires don’t happen all that often, but when things do go wrong, it’s normally down to one of the following three reasons:
1. Manufacturing defects
A bad batch of batteries, a problem on the assembly line that caused a component to be damaged, or the use of the wrong components can all cause devices to fail.
Interestingly, while the media is quick to blame manufacturing problems for device fires and recalls, it’s actually pretty rare thanks to the myriad of safety checks that reputable manufacturers carry out.
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2. Flawed design and counterfeit products
You usually only see this with cheap, poorly made devices. Some of these are made by manufacturers who don’t know what they are doing, and others are made by firms that are clearly cutting corners. Unfortunately, this stuff is flooding popular online outlets, and it can be difficult for the average person to tell the difference between a well-made product and a poorly made one because many times the devices feature fake regulatory markings.
Many of the cheap and counterfeit products don’t contain safety features that products from reputable makers have built into them.
3. Products damaged in use
End users are the most common reason why products become unsafe. Throwing devices about, getting them wet, charging them with the wrong charger, and leaving them to bake in the sun are all bad ideas.
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Quality devices will include safety features to protect against overheating, overcharging, being discharged too much, short-circuiting, and being recharged with the wrong charger. Although these features work to prevent damaged devices from becoming unsafe, nothing is foolproof.
What can you do to protect your family from the dangers?
I don’t expect you to have access to thousands of dollars of test equipment; the truth is that you can spot most dangers without it. In fact, I usually identify about 90% of unsafe products with just a visual inspection.
By following a few simple rules, you practically eliminate all the common causes of fire and explosion.
Buy named-brand products from reputable retailers. Yes, you might be paying a few dollars more for a good-quality charger, cable, or power bank, but this is your life and the lives of your family members that we’re talking about. Avoid too-good-to-be-true deals, social media deals, and shady marketplace sellers. If you suspect you’ve purchased a cheap, poor-quality device, stop using it.
If a device is damaged in any way or showing any signs of overheating, swelling, or deformation, stop using it. This goes for chargers and cords (even frayed charging cords can be dangerous). I recommend checking devices yearly and replacing damaged items promptly.
Don’t allow devices to get too hot, especially when charging. Don’t charge a smartphone in your pocket or sports bag, and don’t leave it on the dash of your car baking in the sun.
Don’t leave a charging device unattended. OK, most of us do that, so at the very minimum, I recommend you don’t put charging items on or near flammable objects. A small lithium battery can quickly turn a wooden table or piece of bedroom furniture into an inferno.
If you find out that a device has been recalled, follow the advice given. Don’t be one of those people who think they can outsmart safety.
If in any doubt, seek professional advice.
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Do not underestimate how quickly a lithium-polymer battery can catch fire and how dangerous they can be. Below are a few videos showing just how bad it can get:
What should you do in the event of a fire?
And if you are unlucky enough to face a burning electrical device:
DO NOT THROW WATER ON THE FIRE! That will make matters much worse and can cause further fires. Use only a suitable fire extinguisher or fire blanket.
Evacuate the building.
Try to avoid breathing in the fumes.
Call the fire department. Don’t be stupid or try to be a hero.
Seek medical attention for any injuries, no matter how small.
I want to reiterate that electronic devices are, on the whole, extremely safe and not something you should lose sleep over. By buying a known brand name from a reputable outlet, and taking care not to abuse or damage that device, you’re very unlikely to have any problems at all.