10 Jan '18
To step up Li-ion battery capacity and increase charging speed, Russian scientists are using a combination of graphene and a vanadium disulfide monolayer as a new anode material.
“The new composite has a 2D structure with graphene and vanadium disulfide as two non-homogenous layers about one nanometer thick. We have shown that Li ions can be bonded both on the surface of such material and between the layers, which results in an increase in specific capacity,” said Maksim Vysotin of the Krasnoyarsk-based Kirensky Institute of Physics in Siberia.
The scientists estimate the composite’s possible capacity at 569mAh per gram of the anode material, which is double that of graphite, a material widely used in today’s Li-ion batteries. Computation has led the team to believe that using the vanadium disulfide / graphene heterostructure does not only improve electron transfer but also makes the material stronger mechanically.
“On top of high capacity, another outstanding feature of the composite is high Li ion mobility inside. That makes it possible to charge the battery faster and/or use the battery to power high power devices. Also, increased ion mobility brings hope that a new such battery will perform well at low temperatures,” said Zakhar Popov of a nanomaterial team at MISiS, a leading technology university in Moscow.