Question 1

How do I calculate Wh from mAh?

Accepted Answer

Use the formula: Wh = (mAh × Voltage) / 1000. For example, a 20,000mAh power bank at 3.7V = (20,000 × 3.7) / 1000 = 74Wh. Most power banks use 3.7V nominal voltage.

Question 2

Can power banks go in checked luggage?

Accepted Answer

No. Power banks (spare lithium batteries) are strictly prohibited in checked baggage on all commercial flights worldwide. They must be carried in your hand luggage/carry-on bag only. This is an IATA, FAA, and EASA requirement.

Question 3

What is the IATA 100Wh limit?

Accepted Answer

The International Air Transport Association (IATA) sets 100Wh as the threshold for unrestricted carry. Power banks under 100Wh are generally allowed without approval. Between 100-160Wh requires airline approval and limits you to 2 units. Above 160Wh is prohibited on passenger aircraft.

Question 4

Is 27000mAh allowed on a plane?

Accepted Answer

A 27,000mAh power bank at the standard 3.7V equals approximately 99.9Wh, which is just under the 100Wh limit. It should be allowed, but we recommend checking with your airline as it's very close to the threshold.

Question 5

What about damaged or swollen power banks?

Accepted Answer

Damaged, defective, or recalled lithium batteries are prohibited from all flights. If your power bank is swollen, cracked, or shows signs of damage, do not bring it on a plane. Dispose of it safely at a battery recycling center.

Question 6

How many power banks can I bring?

Accepted Answer

For power banks under 100Wh, most airlines allow up to 20 spare batteries total. For 100-160Wh power banks, you're typically limited to 2 units and need airline approval. Some airlines like Emirates limit passengers to just 1 power bank regardless of capacity.

Question 7

Do I need approval for batteries between 100-160Wh?

Accepted Answer

Yes. Power banks between 100-160Wh require explicit airline approval before travel. Contact your airline at least 48 hours before departure to request permission. You'll typically be limited to carrying a maximum of 2 such batteries.

Question 8

What are the China (CAAC) specific rules?

Accepted Answer

China's Civil Aviation Administration requires power banks to have: 1) A legible capacity label (mAh/Wh clearly printed), 2) 3C certification mark for Chinese-branded batteries. Additionally, using or charging power banks during flight is prohibited. Batteries without these markings may be confiscated.

Capacity	Watt-hours	Status
10,000 mAh	37 Wh	Allowed
20,000 mAh	74 Wh	Allowed
26,800 mAh	99.16 Wh	Allowed
27,000 mAh	99.9 Wh	Allowed
30,000 mAh	111 Wh	Needs Approval
50,000 mAh	185 Wh	Banned

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