Charge up on moisture in the air Ken Biggs / Alamy Stock Photo

Don’t you hate it when your phone battery dies? In the future, you might be able to recharge your gadget by breathing on it, thanks to a technique that harvests electricity from moisture in the air.

Water droplets might seem an unlikely source of energy, but then can hold a form of static electricity called hygroelectricity, which is thought to be the source of electric charge that causes lightning. This charge can be transferred from droplets to other tiny particles, such as dust.

Researchers have previously …