Nanoflowers improve ultracapacitors

A novel design could boost energy storage.

09/22/2008



Imagine a cell-phone battery that recharges in a few seconds and that you would never have to replace. That's the promise of energy-storage devices known as ultracapacitors, but at present, they can store only about 5% as much energy as lithium-ion batteries, according to a story in MIT’s Technology Review . An advance by researchers at the Research Institute of Chemical Defense, in China, could boost ultracapacitors' ability to store energy.

A capacitor consists of two electrodes with opposite charges, often separated by an insulator that keeps electrons from jumping directly between them. The researchers have developed an electrode that can store twice as much charge as the activated-carbon electrodes used in current ultracapacitors. The new electrode contains flower-shaped manganese oxide nanoparticles deposited on vertically grown carbon nanotubes.

The electrodes deliver five times as much power as activated-carbon electrodes, says Hao Zhang, lead author of the Nano Letters paper describing the new work. The electrode's longevity also compares with that of activated-carbon electrodes, Zhang says: discharging and recharging the electrodes 20,000 times reduced the capacitor's energy-storage capacity by only 3%.

So far, ultracapacitors have been limited to niche applications that require high power and quick, repetitive recharging. For example, the devices provide quick bursts of power to buses, trucks, and light-rail trains over short stretches, and braking replenishes them. If they could store more energy, however, they could be a powerful, long-lasting replacement for batteries in hybrid-electric vehicles and portable electronics.





No comments
The Engineers' Choice Awards highlight some of the best new control, instrumentation and automation products as chosen by...
The System Integrator Giants program lists the top 100 system integrators among companies listed in CFE Media's Global System Integrator Database.
The Engineering Leaders Under 40 program identifies and gives recognition to young engineers who...
This eGuide illustrates solutions, applications and benefits of machine vision systems.
Learn how to increase device reliability in harsh environments and decrease unplanned system downtime.
This eGuide contains a series of articles and videos that considers theoretical and practical; immediate needs and a look into the future.
Sensor-to-cloud interoperability; PID and digital control efficiency; Alarm management system design; Automotive industry advances
Make Big Data and Industrial Internet of Things work for you, 2017 Engineers' Choice Finalists, Avoid control design pitfalls, Managing IIoT processes
Engineering Leaders Under 40; System integration improving packaging operation; Process sensing; PID velocity; Cybersecurity and functional safety
This article collection contains several articles on the Industrial Internet of Things (IIoT) and how it is transforming manufacturing.

Find and connect with the most suitable service provider for your unique application. Start searching the Global System Integrator Database Now!

SCADA at the junction, Managing risk through maintenance, Moving at the speed of data
Flexible offshore fire protection; Big Data's impact on operations; Bridging the skills gap; Identifying security risks
The digital oilfield: Utilizing Big Data can yield big savings; Virtualization a real solution; Tracking SIS performance
click me