Air China power bank rules: 160Wh, no use on board

In checked bags

Power banks may not be carried as checked baggage, carry-on only

With approval

100–160Wh power banks require the carrier's approval to carry

Not allowed

Over 160Wh: power banks not allowed, whether carried on the person or checked

Using it on board

Power banks with a power switch must be kept switched off during the flight

No. Power banks with a power switch must be kept switched off during the flight.

• Power bank rules, airline by airline
• Power banks on Japanese flights