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Are you concerned about lithium battery safety? We’ve all seen news reports about electronic device fires: sudden fires on desks, smoke billowing from airplane cabins, explosions in train cars, even a fire burning a hole in a room while charging at home.
A lithium battery, or more correctly, lithium-ion polymer battery (a.k.a. LiPo, LIP, Li-poly, lithium-poly), is a type of rechargeable battery used in many devices from smartphones to e-bikes. These batteries are generally safe under normal operating conditions, but they do carry a higher risk of explosion and fire than other battery types due to their chemistry and high energy density.
Properly stored and undamaged batteries are not likely to spontaneously combust. However, a lithium battery can release toxic gases, explode, or catch on fire when damaged, improperly charged, or exposed to extreme conditions in which the internal temperature rises uncontrollably. A battery in thermal runaway can emit hot gases, flames, and sometimes even fragments.
Lithium Battery Safety Tips
Most incidents involve:
- Overcharging or overheating
- Physical damage (crushing, puncture, dropping)
- Electrical faults such as short circuits or defective cells
- Counterfeit, off‑brand, or poor-quality batteries
- Faulty or incompatible chargers
- Aging or degraded batteries that become unstable over time
To dramatically lower fire risk:
- Use only manufacturer‑approved chargers and avoid cheap aftermarket ones.
- Immediately stop using a battery that smokes, smells, swells, hisses, or gets unusually hot.
- Charge in open, ventilated areas – not under pillows, on beds, or near flammable materials.
- Never leave lithium batteries unattended while charging, even in a fireproof pouch.
- Store batteries in a cool, dry place away from moisture and heat sources.
- Inspect batteries regularly to make sure they are not overheating, cracked, leaking, or swollen.
- Recycle damaged or old batteries properly — never throw them in household trash.
Traveling with Lithium Batteries
Aviation authorities require lithium batteries to stay in the cabin where fires can be detected and handled immediately. Devices with built‑in batteries (phones, laptops, tablets, cameras) should be placed in carry-on luggage. Spare batteries, power banks, and vape devices are prohibited in checked baggage. (If your carry-on is taken away at the gate to be checked, don’t forget to remove those items!)
If you stow a device in an overhead bin, it must be fully powered off. Never leave a device charging in an overhead compartment. Also, loose batteries can short‑circuit if their terminals touch metal. To prevent this, keep them in their original packaging, or cover the terminals with non‑conductive tape, and place each battery in a separate bag.
How to Store Lithium Batteries
Safe Storage Rules
- Store in a cool, dry, ventilated area (40–80°F).
- Keep batteries 40–70% charged for long‑term storage.
- Keep away from flammable materials.
- Do not store damaged, swollen, or unknown‑condition batteries.
Storage Containers
If you want a safe container for storing lithium batteries, it should have high temperature resistance, shock absorption, venting or pressure‑relief modifications, and a secure closure. It should be rated or designed for battery storage, not document protection.
A standard fireproof safe is not the right choice because it’s built to keep fire out, not to handle a fire starting inside. This distinction matters because lithium battery failures release hot gases rapidly. A sealed safe can trap internal heat and build up pressure until it ruptures violently, turning a battery failure into an explosion.
Here are a few options for lithium battery storage containers:
Specialized Fire‑Rated Lithium Battery Cabinets
- Best option for multiple or high‑capacity batteries
- Designed to contain heat, flames, smoke and gas release
- Meet NFPA/OSHA/UL5800 standards
- These are expensive and more suited for industrial use
Modified Metal Ammo Cans
- A common DIY solution
- Must be vented to prevent explosion (just remove the waterproof seal)
- Can be lined with ceramic fiber insulation
- Like this Ammo Can for Lithium Batteries
LiPo Battery Charging Safe Box
- Double‑wall insulated steel construction to contain heat and flames
- Flame arrestors / soot filters to vent smoke safely
- Fireproof wire pass‑throughs to charge batteries while lid stays closed
- Locking latches to keep the box sealed during a failure
- Like this Mini LiPro Battery Charging Safe Box
LiPo Fire‑Resistant Bags
- Made of non‑conductive, silicone‑coated woven fiberglass cloth
- Good for small batteries (phones, cameras, portable chargers)
- Contain flames briefly but do not handle pressure well
- Like this Lipo Safe Bag or this Lithium Battery Explosion-Proof Bag
Fireproof Bags are Not Magic
A lithium battery safety bag (often called a LiPo bag) may be marketed as fireproof or explosion‑proof, but you should not assume it will reliably “contain” a full lithium battery explosion or thermal runaway event. Its primary function is to limit damage by preventing the fire from spreading to surrounding objects or materials.
Fiberglass/silicone battery pouches are worth using—they’re better than leaving bare batteries on a desk or in a drawer. The soft pouches can hold back flames, but they’re not rigid pressure vessels, and they can’t prevent an explosion or extinguish flames. Moreover, large battery packs (e‑bike, power tools, etc.) can release too much heat for a small bag to absorb or block, and overwhelm the pouch.
How to Put Out a Lithium Battery Fire
If the unexpected should happen, what can you do? Small device fires may be suppressed with water or a standard extinguisher, but the battery must be cooled to prevent re-ignition. Carefully move the device to a well-ventilated area to allow toxic gases to disperse safely, and stand back. A battery in thermal runaway can vent hot gases, flames, and sometimes fragments. Large battery fires (like EVs) require huge volumes of water, and firefighters often let them burn while containing the spread.
Lithium-ion batteries power much of daily life. But when damaged, overcharged, or stored improperly, they can ignite quickly and without warning. Remember to: Use only manufacturer-approved chargers and batteries. Avoid charging devices on beds, couches, or other combustible surfaces. Do not overcharge—unplug once fully charged. Keep batteries away from heat, moisture, and direct sunlight. Stop using batteries that are damaged, swollen, or overheating. Store and charge batteries in a well-ventilated area. Follow proper disposal guidelines, and NEVER throw batteries in the trash. –Cal Fire
Have you ever experienced a lithium battery fire or explosion? Tell us what happened!
