Researchers develop t shirt that could charge your phone

"We wear fabric every day," said mechanical engineering professor Xiaodong Li. "One day our cotton t shirts could have more functions; for example, a flexible energy storage device that could charge your mobile phone or your iPad." The team soaked a regular cotton t shirt in a solution of fluoride, dried it and then baked it at high temperature without oxygen to prevent charring or combustion. The surfaces of the resulting fibres in the fabric were shown by infrared spectroscopy to have been converted from cellulose to activated carbon. Plus, the material retained flexibility and could be folded without breaking. "We will soon see roll up mobile phones and laptop computers on the market," commented Li. "But a flexible energy storage device is needed to make this possible." By using small swatches of the fabric as an electrode, the researchers showed that the 'activated carbon textile' material acts like a capacitor. They then coated the individual fibres with a nanometre thick layer of manganese oxide which greatly enhanced the electrode performance of the fabric to create a stable, high performing supercapacitor. The team also found that the hybrid supercapacitors were resilient – even after thousands of charge-discharge cycles, performance didn't diminish more than 5%. "By stacking these supercapacitors up, we should be able to charge portable electronic devices such as mobile phones," Li noted. The team says it is particularly pleased to have found a method of creating activated carbon fibres without using oil or environmentally damaging chemicals. "Those processes are complicated and produce harmful side products," said Li. "Our method is a very inexpensive, green process."