Vanadium-oxide tapes coated with graphene could become the best-ever electrodes for lithium-ion batteries, high-power accumulators used to charge mobile phones, laptops, and electric cars.
The study, carried out by researchers at the Rice University (Houston – Texas), was recently published in the review Nano Letters.
The stripes produced at the labs of the Rice University are thousands of times thinner than a sheet of paper, but their potential is far greater compared to other available materials. With these devices, a battery can be recharged within a mere 20 seconds and retain 90% of its baseline capacity after more than 1000 cycles.
Professor Pulickel Ajayan, head of the research team, stressed that vanadium oxide had been considered a very useful material in this field for some time, due to its special structure. However, it poses a challenge: like all oxides, it charges very slowly and its electric conductivity is low.
The problem was solved by adding a graphene lattice. Its very high electric conductivity makes graphene a perfect channel for quick electron and ion transit.
“This unique structure promotes a super-fast diffusion of lithium ions and electrons during the charging and discharging process, and was the key to achieve excellent electrochemical performance,” said Shubin Yang, one of the authors of the study.
Click here to read the abstract of the study.
The Editorial Staff
Published on Tuesday, April 9, 2013