Lithium ion battery safety at home comes down to a few habits: buy certified devices, charge with the right charger, never charge on a bed or couch, store batteries away from heat and exits, and recycle them instead of trashing them. If a battery smells, swells, leaks, gets hot or makes odd noises, stop using it.
Lithium-ion batteries power phones, laptops, power tools, e-bikes, e-scooters, toys and even smoke alarms. NFPA explains that they store a lot of energy in a small space. If that energy is released in an uncontrolled way, it makes heat that can turn parts of the battery into flammable and toxic gases.
According to NFPA, these fires start for a handful of reasons:
Physical damage: the battery is crushed, punctured or exposed to water.
Electrical damage: overcharging, or using a charger not designed for the battery.
Extreme temperatures.
Product defects: NFPA notes a small number of batteries are defective and can overheat, catch fire or explode.
NFPA lists heat, smoke, toxic gases and the potential for explosions as the dangers of these fires. That is why prevention and a fast exit matter so much.
Buy certified. Choose devices and batteries listed by a nationally recognized testing laboratory (NFPA).
Use the matching parts. Use only the battery designed for the device and the charging cord that came with it (NFPA).
Keep chargers off soft surfaces. Do not charge a device under your pillow, on your bed or on a couch (NFPA).
Unplug when full. NFPA says not to keep charging a device or battery after it is fully charged.
Mind the temperature. Keep batteries at room temperature when possible, and do not charge them below 32°F (0°C) or above 105°F (40°C) (NFPA, USFA).
Never charge damaged gear. NFPA says not to charge when either the charger or the battery is damaged, and not to modify either one.
Leave repairs to pros. NFPA advises having all repairs done by a qualified professional.
Bigger batteries need extra care. CPSC says it has seen many lithium-ion battery home fires and deaths happen at night, and gives these rules for micromobility products:
Always be present while it charges. Never charge while you are sleeping or when you are not home.
Follow the manufacturer's charging instructions and unplug it when done.
Use only the charger that came with the device or one the manufacturer recommends.
Use a spare or replacement battery only if the manufacturer has confirmed it suits your device. Never use a battery that has been modified or rebuilt by unqualified people, or one made from used or repurposed cells.
Where you charge matters too. NFPA says the safest place to charge e-bikes and e-scooters is outdoors, away from any building and out of direct sunlight. Wherever you charge, NFPA's tip sheet says to choose a flat, dry spot away from children, liquids and tripping hazards, where the bike cannot fall over. And never store batteries where they would block the only exit from a room.
Store batteries, especially spares, away from anything that can burn (NFPA, USFA).
Keep them out of direct sunlight and out of hot cars (USFA).
Avoid very hot or very cold storage spots (NFPA).
Keep them clear of exits, so a battery problem never blocks your way out (NFPA).
When flying, USFA says to take spare, loose lithium-ion batteries out of checked bags and keep them with you on the plane.
NFPA lists these signs. If you notice any of them, stop using the battery or device:
A strange smell
Too much heat
Swelling or any change in shape
A change in color
Leaking
Odd noises, such as popping
NFPA says not to charge, open or repair a damaged battery. For devices damaged by water, it says to ask your local fire department, waste department or the manufacturer how to dispose of them safely.
Signs of trouble: NFPA's tip sheet says that, if it is safe to do so, move the device away from anything that can catch fire, then call 911.
Smoke or flames: get everyone out right away (USFA's advice is simply "Get out quickly"), and call 911 from outside. Do not go back in.
Leave firefighting to firefighters. NFPA notes that firefighters can use water on these fires, but your job is to get out.
Working smoke alarms and a practiced escape plan give you the time you need. See our sister site's guide to smoke alarm placement and testing and our home fire escape plan guide.
Never in the trash or recycling bin. NFPA, USFA, CPSC and EPA all say to keep lithium-ion batteries out of the trash, and NFPA, CPSC and EPA add regular recycling bins. NFPA explains that batteries and the devices holding them can cause fires during transport and at landfills and recyclers.
Take them to a drop-off. NFPA says to use a battery recycling or household hazardous waste collection point. Many stores that sell lots of batteries take them back, and your local waste or recycling center may accept them.
Find a location. EPA points to Call2Recycle, Earth911 and the Consumer Technology Association's Greener Gadgets as ways to find a recycler (EPA notes it does not endorse them).
Recalled products: CPSC says to follow the disposal instructions in the recall notice, and to report a battery problem at SaferProducts.gov.
NFPA's advice is not to keep charging once the battery is full and never to charge under a pillow, on a bed or on a couch. For e-bikes and e-scooters, CPSC is stricter: never charge while you sleep.
Stop using and charging it, and do not open it. If it is hot or smoking, move it away from things that burn only if that is safe, and call 911. Then ask your local waste or recycling center how it takes damaged batteries.
No. Take them to a battery recycling or household hazardous waste drop-off. EPA lists Call2Recycle, Earth911 and Greener Gadgets as places to search.
NFPA says firefighters should use water on lithium-ion battery fires. At home, do not fight it yourself. Get out and call 911.
RoomMend: Safer Home Plans is a free iPhone and iPad app, with an optional RoomMend Plus upgrade, that walks you through your home room by room. If you notice an e-bike charging by the only door or a phone charger on a bed, you can log it in about three taps with an optional photo, then mark it fixed and get a reminder to look again after 30 days. Records and photos stay on your device and it works offline, but it is not a safety certification, so follow the guidance above first.
Get RoomMend free on the App Store