Chinese researchers have developed a new "green" way to boost the performance of lithium-ion batteries with a material derived from silk.

According to Chuanbao Cao from Beijing Institute of Technology, carbon is a key component in commercial Li-ion energy storage devices including batteries and supercapacitors.

Most commonly, graphite fills that role but it has a limited energy capacity. Cao's team wanted to see if they could develop a material using a sustainable source.

The researchers found a way to process natural silk to create carbon-based nanosheets that could potentially be used in energy storage devices. Their material stores five times more lithium than graphite can - a capacity that is critical to improving battery performance.

It also worked for over 10,000 cycles with only a nine percent loss in stability.

"We successfully incorporated their material in prototype batteries and supercapacitors in a one-step method that could easily be scaled up," Cao noted.