New storage batteries based on carbon nanotubes

US researchers have successfully fabricated electric storage batteries for the first time using a random network of carbon nanotubes (CNT). Components have excellent energy storage properties and can be manufactured using " roll-to-roll " techniques or inkjet processing techniques. This means that this component manufacturing technique may be compatible with the characteristics of " printing electronics " (printed electronics).

"Our technique allows the creation of batteries based on simple printing techniques," said group leader George Gruner in Nanotechweb.org, "we can even" print ". "A lot of batteries are as simple as printing newspapers. Maybe someday, we even print a series of batteries like this right at home, just using an inkjet printer."

According to their assumptions, " printed " electronic components, or " plastics, " are components that can be created using single-process printing and can be printed on most surfaces. including raw fabric. However, the problem here is that traditional batteries are not compatible with such devices, including smart cards, electronic newspapers, medical devices or electronic components that can be worn on the body. " To do this simply," print electronics "must have a printing power" - Gruner said in a humorous way.

Figure 1. Random tongue networks of CNT tubes that make up the structure of energy storage batteries (Appl. Phys. Lett. 91, 144104 (2007)).

The team consists of George Gruner and Andreas Kiebele, who developed a battery battery architecture based on elements at nanometer sizes, such as CNT tubes or other nanowires assembled by possible positive materials. Power supply for batteries. The nanowires form a thin, penetrating network or thin films, used as electrodes and electrical contributors for the device."We took advantage of three important properties of this network: high electrical conductivity, large surface area and mechanical toughness," Gruner explained.

In the new designs, the charge collector - often made from metal plates, meshes or thin films in traditional batteries - has been replaced by a random grid of carbon nanotubes ( CNT). This mechanism provides the necessary charge to transport the device electrodes."These batteries are similar to traditional batteries, with similar performance, but with large surface area and high electrical conductivity, networks allow us to gain many advantages from properties. Great material at nanometer size " - Gruner added.

Figure 2. Test product (G. Gruner & Nanotechweb.org).

The team tested this mechanism to create supercapacitors or new generation of storage devices. Here, electrodes (usually using graphite) have also been replaced by CNT. These components discharge extremely fast but the storage capacity seems a bit smaller."They are made from a variety of nanomaterials and use the same technology to make and form a very strong pair, able to provide energy for a variety of electronic components" - Gruner explains. more.

The application of this new type of device can range from the medical field, such as health checks, drug delivery . to security - for example, in smart RFID tags. It can also integrate with solar cell thin film structures for solar storage.

Currently, the group is focusing on optimizing the performance of the equipment and demonstrating the ability to produce on an industrial scale in the next steps . "We have begun to face cost issues but will definitely improve in the future," Grunner said.

The results of this study have just been published in Applied Physics Letters 91, 144104 (2007) .

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According to Nanotechweb.org & American Institute of Physics, Vietnam Physics