Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Nanomaterials: Peapod power

09.02.2011
A new type of composite material with peapod structures can help improve the performance of lithium-ion batteries

Lithium-ion batteries are used to power a wide range of electronic devices, including computers, cameras, digital audio players and calculators. Tremendous effort has been devoted to the development of lithium-ion batteries, especially in improving the efficiency and integrity of the battery electrodes.


Cobalt oxide nanoparticles embedded in carbon fibers (left) to form peapod-like structures improve the lifetime of electrodes in lithium-ion batteries.
Copyright : Left: 2010 ACS. Right: iStockphoto.com/pixhook

This is because during the discharging and charging processes, lithium ions are repeatedly incorporated into and extracted from the electrodes by alloy formation or chemical conversion. These recurring events are known to cause the progressive degradation of the electrodes, irreversibly damaging battery performance.

Yu Wang at the A*STAR Institute of Chemical and Engineering Sciences and co-workers[1] have now demonstrated an elegant strategy to reduce the degradation problem and increase the capacity retention of lithium-ion batteries over many charge–discharge cycles. The strategy involves the use of a composite material with a peapod structure comprising cobalt oxide (Co3O4) nanoparticles embedded in carbon fibers (see image).

Cobalt oxide is a promising material for anodes in lithium-ion batteries because its capacity for holding ions is higher than that of conventional electrode materials, such as tin. In addition, Co3O4 can be easily converted to LiCoO2, which is the material currently used in commercial cathodes. The researchers made the peapod structures by heating cobalt carbonate hydroxide nanobelts coated with layers of polymerized glucose in an inert atmosphere at 700 ºC and then in air at 250 ºC. Electrodes built using the peapod composite had enhanced lithium storage and capacity retention—delivering 91% of the total possible capacity after 50 charge–discharge cycles.

“The Co3O4 nanoparticles act as active materials to store lithium ions and the hollow carbon fibers protect and prevent the Co3O4 nanoparticles from aggregating and collapsing,” says Wang. The carbon fibers also play the role of conducting electrons from the nanoparticles.

According to Wang, aside from the promising application in lithium-ion batteries, the fabrication of the peapod composite is an achievement in itself, as it is the first time that such isolated magnetic nanoparticles embedded in hollow fibers have been produced. Scanning electron microscopy revealed that the peapod composite exhibits a uniform morphology, with pod lengths of up to several micrometers and pod diameters of as small as 50 nanometers. The researchers believe that their method could be extended to generate encapsulated nanoparticles using a wide range of materials with applications beyond lithium-ion batteries, for example, in gene engineering, catalysis, gas sensing and the manufacture of capacitors and magnets.

The A*STAR-affiliated researchers contributing to this research are from the Institute of Chemical and Engineering Sciences.

Journal information

[1] Wang, Y. et al. Designed functional systems from peapod-like Co@carbon to Co3O4@carbon nanocomposites. ACS Nano 4, 4753–4761 (2010).

Lee Swee Heng | Research asia research news
Further information:
http://www.research.a-star.edu.sg/research/6282
http://www.researchsea.com

More articles from Materials Sciences:

nachricht Game-changing finding pushes 3D-printing to the molecular limit
20.06.2018 | University of Nottingham

nachricht Creating a new composite fuel for new-generation fast reactors
20.06.2018 | Lobachevsky University

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Temperature-controlled fiber-optic light source with liquid core

In a recent publication in the renowned journal Optica, scientists of Leibniz-Institute of Photonic Technology (Leibniz IPHT) in Jena showed that they can accurately control the optical properties of liquid-core fiber lasers and therefore their spectral band width by temperature and pressure tuning.

Already last year, the researchers provided experimental proof of a new dynamic of hybrid solitons– temporally and spectrally stationary light waves resulting...

Im Focus: Overdosing on Calcium

Nano crystals impact stem cell fate during bone formation

Scientists from the University of Freiburg and the University of Basel identified a master regulator for bone regeneration. Prasad Shastri, Professor of...

Im Focus: AchemAsia 2019 will take place in Shanghai

Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.

Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...

Im Focus: First real-time test of Li-Fi utilization for the industrial Internet of Things

The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.

Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.

Im Focus: Sharp images with flexible fibers

An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.

Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Munich conference on asteroid detection, tracking and defense

13.06.2018 | Event News

2nd International Baltic Earth Conference in Denmark: “The Baltic Sea region in Transition”

08.06.2018 | Event News

ISEKI_Food 2018: Conference with Holistic View of Food Production

05.06.2018 | Event News

 
Latest News

Creating a new composite fuel for new-generation fast reactors

20.06.2018 | Materials Sciences

Game-changing finding pushes 3D-printing to the molecular limit

20.06.2018 | Materials Sciences

Could this material enable autonomous vehicles to come to market sooner?

20.06.2018 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>