Professor Jie Tang, Group Leader of the 1D Nanomaterials Research Group of the Materials Processing Unit, National Institute for Materials Science, and Mr. Qian Cheng, a doctoral student and NIMS Junior Researcher in the same Group, have succeeded in dramatically increasing the energy density of supercapacitors, which are used to store electrical energy.
Professor Jie Tang, Group Leader of the 1D Nanomaterials Research Group of the Materials Processing Unit (Unit Director: Yoshio Sakka), National Institute for Materials Science (President: Sukekatsu Ushioda), and Mr. Qian Cheng, a doctoral student and NIMS Junior Researcher in the same Group, have succeeded in dramatically increasing the energy density of supercapacitors, which are used to store electrical energy. This was realized by developing a new electrode in which graphene nanosheets are stacked in a layered structure with carbon nanotubes sandwiched between the graphene layers.
Various new batteries, such as nickel metal hydride batteries, are currently being developed with the aims of achieving higher efficiency and higher energy storage for electric power supplies. In comparison with batteries, capacitors have a larger output power density to enable rapid charging, excellent durability to allow operations in both higher and lower extreme temperatures, better cyclicity for recharging repeatedly over a long period, and are also safer. However, it has been as a great technical challenge to realize high energy density due to the relatively low specific capacity of the conventional capacitor devices.
In order to achieve a revolutionary increase in density of energy storage, Professor Tang and her team, in collaboration with Professor Lu-Chang Qin of the University of North Carolina at Chapel Hill in the United States, have designed and developed a graphene-based composite structure, in which graphene is used as the base material of the capacitor electrodes and carbon nanotubes (CNT) are inserted between the graphene sheets. In this structure graphene offers a far larger specific surface area (2630 m2/g) than the conventional materials and the CNTs function as spacers as well as conducting paths to enable adsorption of a larger quantity of electrolyte ions on the graphene surface. With this graphene-CNT composite as the capacitor electrodes, Professor Tang has obtained a high energy density of 62.8 Wh/kg and output power density of 58.5 kW/kg using organic electrolyte. By using an ionic liquid as the electrolyte, they have achieved an energy density of 155.6 Wh/kg, which is comparable to that of nickel metal hydride batteries.
Among the many industrial applications of capacitors, the new capacitors developed in this research offer promises as power sources for electric and hybrid vehicles, which require high energy density. As the current production processes are also inexpensive and can be scaled up, large expectations are placed on practical applications.
This research achievement is published in the latest issue of Physical Chemistry Chemical Physics, a scientific journal published in London by the Royal Society of Chemistry.
Further reports about: > CNT > Charging > Graphene-Based Electronic Devices > Materials Science > NIMS > Speed > Success > Supercapacitors > carbon nanotubes > electrical energy > energy density > energy storage > hybrid vehicle > industrial application > metal hydride > nanomaterials > production process
Melting solid below the freezing point
23.01.2017 | Carnegie Institution for Science
An innovative high-performance material: biofibers made from green lacewing silk
20.01.2017 | Fraunhofer-Institut für Angewandte Polymerforschung IAP
For the first time ever, a cloud of ultra-cold atoms has been successfully created in space on board of a sounding rocket. The MAIUS mission demonstrates that quantum optical sensors can be operated even in harsh environments like space – a prerequi-site for finding answers to the most challenging questions of fundamental physics and an important innovation driver for everyday applications.
According to Albert Einstein's Equivalence Principle, all bodies are accelerated at the same rate by the Earth's gravity, regardless of their properties. This...
An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...
Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...
Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.
While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...
Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales
Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...
19.01.2017 | Event News
10.01.2017 | Event News
09.01.2017 | Event News
24.01.2017 | Earth Sciences
24.01.2017 | Life Sciences
24.01.2017 | Physics and Astronomy