Soon, charge portable electronics in 10 minutes

Researchers have developed a new architecture for lithium-ion battery anodes that could enable charging of portable electronics in 10 minutes, instead of hours.
Scientists at the University of California, Riverside Bourns College of Engineering developed the new three-dimensional, silicon-decorated, cone-shaped carbon-nanotube cluster architecture for lithium ion battery anodes.
Lithium ion batteries are the rechargeable battery of choice for portable electronic devices and electric vehicles.
However, batteries in electric vehicles are responsible for a significant portion of the vehicle mass. And the size of batteries in portable electronics limits the trend of down-sizing.
Silicon is a type of anode material that is receiving a lot of attention because its total charge capacity is 10 times higher than commercial graphite based lithium ion battery anodes.

Replacing the commonly used graphite anode with silicon anodes will potentially result in a 63 per cent increase of total cell capacity and a battery that is 40 per cent lighter and smaller.

Researchers have now developed a novel structure of three-dimensional silicon decorated cone-shaped carbon nanotube clusters architecture via chemical vapour deposition and inductively coupled plasma treatment.
Lithium ion batteries based on this novel architecture demonstrate a high reversible capacity and excellent cycling stability.
The architecture demonstrates excellent electrochemical stability and irreversibility even at high charge and discharge rates, nearly 16 times faster than conventionally used graphite based anodes, researchers said.

The ultrafast rate of charge and discharge can be attributed to two reasons, said Wei Wang, lead author of the study published in the journal SMALL.
One, the seamless connection between graphene covered copper foil and carbon nanotubes enhances the active material-current collector contact integrity which facilitates charge and thermal transfer in the electrode system.
Two, the cone-shaped architecture offers small interpenetrating channels for faster electrolyte access into the electrode which may enhance the rate performance.