Airline passengers have been warned of the rising risk from lithium batteries on planes.Rechargeable lithium batteries, such as power banks and vapes, are a fire risk that could be uncontrollable if packed in checked baggage.Ahead of the big summer getaway – where more than 60 million people are expected to be flying – the UK’s Civil Aviation Authority (CAA) has told all passengers to make sure they take their batteries inside the cabin with them.The warning comes as new data has revealed the scale of the risk, with lithium battery incidents now occurring around twice a week. More than 100 million batteries may be incorrectly packed, according to the CAA – based on data showing the average number of devices carried being four, as well as the number of passengers travelling and the number of people who don’t know the rules.Reports of overheating or malfunctioning passenger devices nearly doubled between 2024 and 2025, CAA figures show, following a 98 per cent year-on-year increase. Cases of lithium battery-powered devices being incorrectly packed in checked baggage also rose by 91 per cent in 2025. As such, travellers have been instructed to take items such as mobile phones, vapes and power banks on board with them. Passengers have been warned of the great risk of packing lithium batteries in checked-in bags Devices such as portable chargers should be taken inside the cabin – and not charged during the flightPlus, travellers should never charge a power bank on a flight.Additionally, it is important to turn off laptops completely if they’re going to be put in check-in bags.Getting it wrong could lead to your bags being removed from the flight, causing significant delays – or, even worse, result in a fire that may be impossible to contain.Giancarlo Buono, director of aviation safety at the UK CAA, said: ‘Flying is by far the safest way to travel and we want to keep it that way.’Pack right for a safe flight, and that means don’t put your batteries in your checked bag. Take them into the cabin with you. This simple tip will make your flight safer for you, and the other passengers you’re flying with.’Despite the rise in incidents, passenger awareness of the risk remains low – 36 per cent of travellers are unaware of the dangers of packing batteries in checked baggage, even though 92 per cent fly with a mobile phone, 55 per cent with a laptop and 49 per cent with a power bank – suggesting hundreds of batteries could be incorrectly packed on a typical flight.The average person now takes four different lithium-powered devices on trips, meaning there are over 2,000 on a busy Airbus A380 flight. This means the fire risk posed by lithium batteries is now the number one safety risk to aircraft, according to the CAA. This also applies to other rechargeable lithium batteries, for instance in vapesPower banks and vapes are some of the highest risk items and must always be taken with you into the cabin. You cannot fly with more than two power banks. You must never charge the power bank itself on board the aircraft but you may be able to charge other devices from the power bank – check with the airline beforehand or on the CAA website. Tim Alderslade, chief executive of Airlines UK, said: ‘UK airlines support this important campaign. Flying is the safest form of travel but as the number of electronic devices we use increases, the risk of lithium battery incidents is a growing challenge. ‘Whilst pilots and cabin crew are trained to deal with any situation the best outcome is always prevention, which starts when passengers pack their bags. ‘Electronic devices like tablets, power banks and vapes belong in your hand luggage, not the hold. We’d urge every passenger heading away this summer to take a moment to check before they zip up their bag.’