US spare lithium battery ban now in effect

The US Department of Transportation's new regulations governing batteries in airline luggage came into effect on January 1, so if you're thinking of flying into the US with a bagful of gadgets, you'll need to think about what batteries you pack.

In short, the new regulations prohibit the carriage of loose lithium batteries in checked luggage and batteries in carry-on luggage are only allowed if they're either installed in a device or carried inside a plastic bag.

Common consumer electronics such as cameras, mobile phones and most laptops are still allowed in carry-on and checked luggage. However, the rule now limits individuals to bringing only two spare rechargeable lithium batteries in carry-on baggage.

The new rules are intended to reduce the risk of fires caused by the spontaneous combustion of lithium batteries. Quite how keeping a battery installed in a device or better yet, inside a plastic bag, is intended to prevent this isn't explained.

"Doing something as simple as keeping a spare battery in its original retail packaging or a plastic zip-lock bag will prevent unintentional short-circuiting and fires," said Krista Edwards, Deputy Administrator of the U.S. Department of Transportation's Pipeline and Hazardous Materials Safety Administration.

It's worth noting that a) the new rules only apply to spare batteries and b) there are no regulations in place to prevent you taking batteries from the UK to the US - just don't expect to bring them back again if you flout the new rules.

The rules also only apply to lithium batteries, like the rechargeable ones used by most electronic gadgets and not the alkaline cells that make up most AA and AAA batteries. Like the one in our photo, in fact...

[ US Department of Transport battery safety tips]