Ever wondered why airlines care so much about batteries?
It’s because lithium batteries can catch fire if damaged, shorted, or overcharged. Inside each battery, a chemical reaction stores energy. But if something goes wrong—like overheating or crushing — that energy can turn into flames fast.
There have been real incidents. In 2016, a spare battery caught fire on a Delta flight. Luckily, the crew acted quickly. But not every case ends well.
In this article, you’ll learn what batteries are allowed, how to pack them, and what mistakes to avoid. We’re Hongyitai, a lithium battery factory with 10 years of experience. We know how to keep batteries safe—and we’ll help you fly worry-free.
Before you fly, it’s important to know the rules about lithium batteries.
The TSA (Transportation Security Administration) says you can bring lithium batteries in your carry-on bag, but not always in checked luggage. The FAA (Federal Aviation Administration) and IATA (International Air Transport Association) also have rules to reduce fire risks.
Here’s the key:
- Carry-on: Allowed, even for spare batteries
- Checked bags: Only batteries inside devices, no spares
Most airlines limit batteries to 100 watt-hours (Wh). Some allow up to 160Wh with approval.
Not sure what your battery size is? Use this simple formula: mAh ÷ 1000 × Volts = Wh You can also check out our quick guide to convert watts, amps, and volts.
Understanding these limits helps you avoid delays, fines, or worse—confiscated batteries at the gate.
Types of lithium batteries and their restrictions
Not all lithium batteries are the same. The two most common types are lithium-ion and lithium metal batteries.
Lithium-ion batteries are rechargeable. They’re used in phones, laptops, and power banks. Lithium metal batteries are not rechargeable and have more energy in a smaller size. They’re often found in watches and medical devices. Learn more here.
Airlines treat spare batteries differently from those installed in a device.
- Spare batteries must go in your carry-on, with terminals covered.
- Installed batteries can usually stay in the device, even in checked bags (but check the airline’s policy).
Power banks count as spare batteries. For example, a 20,000mAh phone charger is a power bank and must be carried in your cabin bag, not your checked luggage. Always check the watt-hour rating before you fly.
Battery capacity limits: what’s allowed?
Airlines don’t just care about the type of battery—they care about its size, too.
Battery size is measured in watt-hours (Wh). This tells how much energy the battery holds. Most airlines follow this rule:
- Under 100Wh: Allowed in carry-on without approval
- 100–160Wh: Allowed, but you need airline approval
- Over 160Wh: Not allowed on passenger flights
If you’re not sure about your battery size, check the label or calculate it using volts and mAh. Many laptop and power bank batteries are under 100Wh, so they’re usually fine.
Stick with under 100Wh to stay safe and avoid travel delays.
How to pack lithium batteries for air travel
Packing your batteries the right way keeps your flight safe—and avoids trouble at security.
Always protect battery terminals so they don’t touch metal or other batteries. You can use tape or put each battery in a separate plastic bag. This helps prevent short circuits, which can lead to overheating or fire.
Spare batteries should be in your carry-on, not checked bags. Label them if possible, especially larger ones, and store them where they won’t get crushed.
Traveling with kids? Don’t forget tablets or toys often use lithium batteries. A mom once had her kid’s toy fire truck pulled at security because of a loose battery. Another traveler had a drone battery flagged because it wasn’t packed safely.
Simple packing steps can prevent big problems. Take the time to do it right.
Flying with devices containing lithium batteries
You can fly with most everyday electronics, but there are still rules.
Here’s a quick comparison:
| Device | Allowed in Carry-On | Allowed in Checked Bag | Notes |
| Laptop | Yes | Yes (with care) | Turn off before checking |
| Phone | Yes | Yes | Keep easily accessible |
| Tablet | Yes | Yes | Same as phones |
Medical devices like CPAP machines or monitors are allowed, but tell the airline in advance. Bring backup batteries, and pack them like spares—with terminals protected and in your carry-on.
Smart bags are allowed only if the battery can be removed. If it can’t be removed, you won’t be able to check or carry it on. Always check your airline’s policy before flying.
How airlines handle damaged or wwollen batteries
If security sees a swollen, cracked, or leaking battery, they may take it away immediately. You won’t be allowed to fly with it.
To safely get rid of a damaged battery before your flight:
- Don’t throw it in the trash
- Find a battery disposal box at the airport
- Ask airline or TSA staff for help
- Store it in a fireproof bag until disposal
Always check your batteries before packing. It can save you time—and keep everyone safe.
International travel: rules may differ
Battery rules can change from country to country. Here’s how five places differ:
- USA: Follows TSA and FAA rules (100Wh limit, spares in carry-on)
- UK: Similar to US, but some airlines require approval for 100–160Wh
- China: Strict screening; often limits battery quantity
- Australia: Allows up to 160Wh with approval
- Japan: Requires clear labeling and sometimes airline notice
For layovers, always follow the rules of each country and airline you pass through—not just your final destination.
Airline-specific battery policies
Different airlines have slightly different rules. Here are a few:
- Delta: Allows up to 100Wh in carry-on; 100–160Wh with approval – delta.com
- Emirates: Batteries over 100Wh need airline OK – emirates.com
- Qantas: Max 160Wh, must be in carry-on – qantas.com
- Lufthansa: Up to 100Wh allowed freely – lufthansa.com
Always check your airline’s website before flying. Rules can change at any time.
Tips for business travelers carrying multiple batteries
If you travel with several batteries, keep them organized.
Use a battery case or pouch to separate each one. Cover the terminals and label them if possible. At the airport, declare them at security. This saves time and avoids confusion.
Well-packed batteries show you’re prepared—and help you pass through screening smoothly.
Common mistakes to avoid when flying with batteries
Many travelers make simple battery mistakes that cause delays.
- Putting spare batteries in checked bags is not allowed. Always carry them with you.
- Leaving terminals exposed can cause short circuits. One traveler had a battery spark in their backpack because it touched loose coins.
- Bringing power banks over 160Wh is not allowed on most flights. Always check the size before packing.
Avoid these issues by double-checking your bags before you head to the airport.
What to do if your battery is denied at security
If your battery is too big or packed wrong, security may stop you.
You have a few options:
- Use a smaller battery under 100Wh
- Ship the battery ahead using a certified courier
- Leave it behind if no safe option is available
If your battery triggers an alert, TSA may open your bag, test it, or even remove it. Stay calm and follow their instructions. It’s all about keeping your flight safe.
How to travel with drones and lithium batteries
Drone batteries are usually lithium-ion and must follow airline rules.
You can carry them in your carry-on only. Discharge them to about 30–50% before flying. Wrap terminals or place each battery in a fireproof bag or original case.
If you’re flying to a trade show with gear, like a drone pilot we worked with, pack smart. He used labeled cases and got airline approval in advance—no delays at security.
Frequent travelers and digital nomads should keep battery sizes under 100Wh and always carry extras safely packed and declared.
Safe recharging during travel
You can charge devices on planes if outlets are available, but avoid charging large power banks in-flight.
At airports or hotels, follow these tips:
- Use only your own charger
- Avoid public USB ports (they may carry risks)
- Don’t leave batteries charging unattended
- Keep chargers away from flammable materials like bedding or paper
Charge smart. Stay safe.
Emerging tech and future regulations
Battery tech is getting safer. New designs include solid-state batteries, which are less likely to catch fire. As tech improves, airlines may allow larger or different battery types.
Groups like ICAO and UL are updating global safety standards. Some shippers now use x-ray and AI tools to find unsafe batteries in cargo.
More insurers also offer battery risk coverage, especially for commercial shipments. In the future, expect tighter rules—but also safer travel.
Conclusion
Traveling with lithium batteries doesn’t have to be hard. You can also explore alternative power options like AA-powered gear or solar chargers.
Before flying, check your battery size, pack it right, and follow airline rules.
We’ve covered what you need to know—and answered your key questions.
Still unsure about your battery? Contact us at Hongyitai. We’ll help you check if it’s safe to take on a plane.
FAQs
Can I take a 20000mAh power bank on a plane?
Yes, if it’s under 100Wh. Most 20000mAh banks are around 74Wh.
How many spare batteries can I carry?
Most airlines allow up to 2 spare batteries (100–160Wh) with approval. Smaller ones usually have no set limit.
Can I fly with lithium batteries in my camera gear?
Yes. Keep spares in your carry-on, terminals covered.
What happens if I break the battery rules?
Security may confiscate your battery or delay your flight.
