UK CAA warns travelers to keep lithium batteries in cabin

Aviation authorities have issued an urgent warning to travelers ahead of the summer travel season, stating that lithium batteries pose the single greatest safety risk to aircraft. The UK Civil Aviation Authority (CAA) is urging all passengers to ensure portable chargers, vapes, mobile phones, and other devices containing rechargeable lithium batteries are carried only in the cabin, never in checked baggage.

The warning follows a sharp increase in incidents. CAA data shows reports of overheating or malfunctioning passenger devices nearly doubled between 2024 and 2025. Cases of lithium battery-powered devices being incorrectly packed in checked baggage rose by 91 percent last year. Authorities now estimate that lithium battery incidents occur approximately twice a week, with over 100 million batteries potentially being packed incorrectly by travelers.

The core danger lies in the nature of lithium-ion batteries, which can store significant energy in a compact space. If damaged, defective, or improperly handled, they can enter a state called thermal runaway, triggering aggressive, rapidly spreading fires that release toxic fumes. A fire originating in an aircraft's cargo hold is far...