Some travellers were unable to access WiFi in their hotel without incurring an added charge.

London - A flat smartphone battery usually sparks a frantic scrabble for a charger – providing you’ve remembered it.

Imagine how much easier it would be if the power was automatically topped up, even while the mobile’s in your pocket.

Scientists in Korea now think they have cracked the problem with a wireless device that can charge up to 40 phones at the same time – from up to 15 feet (about 4.5 metres) away.

Inventor Chun Rim said his creation could lead to a future without tangled charger wires and phones that are powered up as we walk about.

He said: “Just like we see wi-fi zones everywhere today, we will eventually have many wi-power zones at such places as restaurants and streets that provide electric power wirelessly to electronic devices.”

Although some wireless chargers are on the market, they only work when phones are placed on them.

Professor Rim, a nuclear and quantum engineer, believes he has solved a problem that experts at the Institute of Physics say has foxed scientists until now.

His wireless system can even transmit enough energy to power a large TV and three fans from a distance.

The catch is that the prototype is 10ft long and costs £3 000 (about R54 000), but Prof Rim believes that smaller and cheaper versions will be on the market in less than five years. - Daily Mail