Power Bank Over 160Wh in Korea 2026: Banned on Flights and the Seoul Subway

Airline rules measure capacity in Wh (watt-hours), not mAh — if a device only shows mAh, multiply by the voltage and divide by 1,000 to convert (a 20,000mAh unit works out to roughly 74Wh). Airlines generally allow power banks of 100Wh or less in the cabin without restriction or with a per-airline cap (commonly around five units), require airline approval at check-in or security for 100–160Wh units (usually capped at two), and ban anything over 160Wh from both the cabin and checked baggage. At every capacity level, power banks must travel in the cabin, never in checked baggage, and can't be charged, used, or stored in the overhead bin during flight. Separately, Seoul Metro revised its passenger transport terms after a lithium-battery fire at Hapjeong Station in September 2025, and from July 1, 2026 it restricts bringing lithium batteries over 160Wh and lithium-powered personal mobility devices such as e-scooters and e-bikes into subway stations — mobility aids for people with disabilities are exempt. What specific action is taken against a violation is not stated clearly in the official materials. This was checked on 2026-11-03 on the Herald Business (heraldk.com) article screen on the Seoul subway battery ban, and on EVA Air's official baggage restrictions page.