AVIATION safety experts have warned of the dangers of lithium ion batteries on flights after passengers were forced to evacuate a Ryanair plane as a battery operated phone charger caught fire.

The battery pack was charging a passenger’s mobile device while the flight was grounded at a Barcelona airport.

Dramatic vision shows the charger, which burnt a hole in an aircraft seat before being knocked to the floor, engulfed in flames.

As the cabin filled with smoke the crew organised an emergency evacuation, with panicked passengers fleeing the plane via inflatable slides.

People were so eager to exit they failed to follow safety procedures limiting one person to the slide at a time. Instead, there was a pileup with vision showing up to eight people escaping at once.

All passengers on board were safely transferred to another plane while the crew dealt with the mobile charger.

Ryanair released a statement informing passengers they were allowed to carry two spare lithium ion batteries in carry-on baggage, which must be individually protected to prevent short circuits.

“Battery terminals must be either recessed or packaged so as to prevent contact with metal objects including terminals of other batteries,” the statement read.

Ryanair is far from alone, with battery-related fires considered relatively common on aircraft. The latest US Federal Aviation Administration figures reveal incidents occur once every six weeks.