飛行機に予備バッテリーを持ち込める？（米国TSA・CATSA規則）

持込可：100Wh以下のモバイルバッテリーは機内持ち込み可能です。100〜160Whは航空会社の承認が必要（最大2個まで）。

不可：モバイルバッテリーは予備リチウム電池に該当するため、火災危険防止により受託手荷物への預け入れは禁止されています。

Standard carry-on baggage size allowances apply; TSA publishes no individual numerical cap for personal use.

Yes, passengers may use Batteries during flight in compliance with crew instructions.

Power banks and lithium batteries under 100 watt-hours do not require formal declaration at domestic security checkpoints. However, if your spare battery is between 100 and 160 watt-hours, you must declare it to your airline ticket counter prior to boarding for carrier safety approval, and declare any damaged or recalled units.

If a power bank or spare lithium battery is discovered in checked luggage, airport baggage screeners will remove and confiscate it without passenger notification to prevent cargo compartment fires. At security checkpoints, unlabelled banks or units exceeding 160 watt-hours will be denied boarding and surrendered to security.