Coils of carbon nanotubes can be used to make lightweight, stretchable batteries.

Huisheng Peng and his team at Fudan University in Shanghai, China, twisted together several nanotube fibres and found that they had high electrical conductivity, even when stretched up to three times their initial length.

The team incorporated lithium-based nanoparticles into the springy fibres to make a lithium-ion battery, which also performed stably after being stretched. The device is smaller and lighter than batteries that are built on elastic substrates, and can store more charge than such stretchy batteries of similar weight.

The device could be used in 'smart' clothing and other applications, the authors say.

Angew. Chem. Int. Ed. http://doi.org/f2vxwm (2014)