Chinese space scientists use water heat to charge mobile phone

BEIJING -- What if you could charge your mobile phone without conventional electricity, but with a bottle of hot water instead? Space thermoelectric technology could soon make this sustainable solution a reality.

Thermoelectric devices are made from materials that can convert a temperature difference into electricity. Previous researches have suggested that thermoelectric devices can harvest wasted heat and produce electrical energy to back up the battery on spacecraft.

Chinese scientists are now hoping to take advantage of space thermoelectric technology to benefit people's daily life.

Researchers at the China Academy of Launch Vehicle Technology, one of the country's rocket makers, have developed a type of insulated water bottle equipped with a thermoelectric chip that can turn water heat into electricity to charge a mobile phone.

As mobile phones have gotten more powerful processors and larger touch screen interfaces, their power requirement has correspondingly increased. However, people often face the problem of charging their phones, especially when traveling on trains or camping in mountains, said lead researcher Ma Wei.

"Our solution to this problem is a water bottle-based thermoelectric device, a heat source to generate electricity," Ma said, adding that the invention does not require any electrical sources.

A demonstration video showed that the thermoelectric device was embedded in the bottle cap, which has a USB charging port on it. When a researcher connected an iPhone to the bottle with a cable, the battery icon on the screen appeared green with a lightning bolt indication in the middle.

"We have found that the water bottle can provide 20 to 30 minutes of electricity after we poured 300 to 500 milliliters of boiling water into it," said Sheng Jiang, a member of the research team.

The bottle can also provide electricity for laptops, cameras and other low-power household appliances.

Researchers are now seeking to forge cooperation with enterprises to market the concept. The product is likely to be priced from 150 yuan (about 23 U.S. dollars) to 200 yuan.

A thermoelectric chip might make the bottle 200 grams heavier than the same size product on the market, but Sheng said it would be easy to carry as researchers have reduced the bottle weight by the use of a light heat insulation material, originally created for spacecraft, to replace stainless steel container.

Emphasizing the safety of the invention, Sheng said it produces low voltage and has no risk of short circuit.