How to Tell If Your Rechargeable Battery Is About to Explode

There’s a non-zero chance that the lithium battery in your device might, well, explode. Between 2012 and 2017, the U.S. Consumer Product Safety Commission estimates at least 25,000 fires involving these batteries—and this is still happening today. In 2023 alone, New York City reported 200 fires related to lithium-ion batteries. Sure, some of these fires may be related to your dog using your phone as a chew-toy, but these rechargeable batteries can—and do—spontaneously explode into flames.

The good news is that there are warning signs that your rechargeable device’s battery is going to have an explosive moment.

Battery warning signs

Batteries work using chemical reactions to move electrons from one material to another, and that chemical reaction can go sideways under a variety of conditions—but there will usually be warning signs:

• Heat. Rechargeable batteries generate heat as part of their normal operation—your phone can get as hot as 95 degrees under normal conditions and feel warm to the touch, for example. But if your device is too hot to touch, that’s a sign that something is very wrong. If you’re aware of your device being unusually hot, it might be about to explode.

• Swelling. Lithium-ion batteries can swell due to a combination of heat and the buildup of gases. By itself, swelling doesn’t necessarily mean your battery is about to explode—but if your device exhibits any other signs in addition to swelling, be ready to run.

• Smoke. White or gray smoke is a sign that the battery is going to explode very soon. If you see any kind of vapor coming from your device, it’s best to assume you’re about to see some fireworks.

• Sound. Batteries that are on their way towards pyrotechnics often make hissing or bubbling sounds.

If you notice one or more of these warning signs, it’s best to assume the battery is going to catch fire immediately and take steps to protect yourself.

What to do if your battery is about to explode

If you suspect one of your rechargeable batteries is going to explode, take the following steps immediately:

• If you see smoke or sparks, evacuate the area.

• Protect your hands. Don’t handle the device with your bare hands. Find something to use—tongs can be used for smaller devices, or you can use oven mitts, towels, or literally anything that can serve as a buffer between you and the small bomb you’ve discovered in your house.

• Turn off and unplug the device. Disconnect it from an outlet and power the device down, if you can.

• Carefully move the device. Don’t jostle or toss the device. Move it carefully to an isolated spot where flames can be contained—someplace with a concrete floor like a garage, for example, or an exterior location on pavement. If you have a fireproof strongbox or document safe you can place the device inside it, but you should still move it to a location as far away from your living area as possible.

If the device catches fire, you can use a standard fire extinguisher (class D if you have one) to suppress the flames, or a spray of water from a hose. If it’s a large device like an eBike, it’s best to call your local fire department.