fantastic plastic

New Scientist is reporting on printable batteries with carbon nanotube (CNT) electrodes.

The batteries were created by George Gruner and colleagues at the University of California in Los Angeles, US, and use the same zinc-carbon chemistry as ordinary non-rechargeable batteries.

To make the battery, a layer of nanotubes is first deposited in the form of “nanotube ink” onto a surface. This layer acts as the charge collector, which removes current from the battery.
Next, a layer of nanotube ink mixed with manganese oxide powder and electrolytes, which carries charge within the cell, is applied on top. This layer acts as the cathode. Finally, a piece of zinc foil – the anode – is applied.
“The batteries are similar to conventional batteries,” says Gruner, “with the electrically conducting nanoscale networks replacing conventional metals and electrodes.”

The researchers also made supercapacitors using the inking technique and plan to combine these with batteries for applications requiring more power.
Furthermore, since both printed batteries and supercapacitors can be made entirely at room temperature, it should be possible to mass-produce them using established printing methods, Gruner says.

IDTechEx points out that

Professor Gruner is also Chief Technical Officer of Unidym Inc a company he funded in 2005 which focuses on nano-structured materials applications for flexible/transparent electronics.

This subsidiary of Arrowhead Research is developing printed carbon nanotube (CNT) technology for applications such as transparent electrodes, thin film transistors, and fuel cells.
The work has been published in Applied Physics Letters.

Researchers at Rensselaer Polytechnic Institute have developed thin, flexible energy storage devices consisting of more than 90 percent cellulose. The paper is infused with aligned carbon nanotubes (electrodes), and an electrolyte (e.g. an ionic liquid). The technology allows to fabricate batteries, supercapacitors, or devices which combine both functions.

According to the press release, the devices can be biocompatible

and these new hybrid battery/supercapcitors have potential as power supplies for devices implanted in the body. The team printed paper batteries without adding any electrolytes, and demonstrated that naturally occurring electrolytes in human sweat, blood, and urine can be used to activate the battery device.
“It’s a way to power a small device such as a pacemaker without introducing any harsh chemicals – such as the kind that are typically found in batteries — into the body,” Pushparaj said.

Regarding manufacturing:

The materials required to create the paper batteries are inexpensive, Murugesan said, but the team has not yet developed a way to inexpensively mass produce the devices. The end goal is to print the paper using a roll-to-roll system similar to how newspapers are printed.

The work has been published in PNAS (Flexible energy storage devices based on nanocomposite paper), and a patent has been filed.

Supercapacitors or ultracapacitors use electrodes with very high surface area (e.g. porous activated carbon) and are currently used in niche application such as hybrid vehicles.
Among the advantages over electrochemical batteries are the high charge/discharge rate and stability. However, energy densities are relatively low compared to traditional batteries.

New electrode materials with increased surface area have the potential to make hypercapacitors attractive for a wider range of mobile applications.
The approach developed at MIT’s Laboratory of Electromagnetic and Electronic Systems (LEES), uses vertically-aligned single-walled carbon nanotubes.
From the MIT Technology Review:

Ultracapacitors could allow laptops and cell phones to be charged in a minute. And unlike laptop batteries, which start losing their ability to hold a charge after a year or two, they could still be going strong long after the device is obsolete. “Theoretically, there’s no process that would cause the [ultracapacitor] to need to be replaced,” says professor John Kassakian, another of the researchers.

The main hurdle the new technology is likely to face is not technical but economic. “The nanomaterials are probably a hundred or a thousand times more expensive, today, than the materials that we use,”

Other large surface area materials for ultracapacitors include carbon aerogels and barium titanate.

According to Physorg

NEC Corporation today announced that it is developing a high-power organic radical battery (”ORB”) used to protect IT equipment such as desktop PCs from losing data during power supply interruption. […]

ORB is a new class of rechargeable battery being uniquely developed by NEC, which uses the electrochemical reaction of organic radical compounds. This technology was initially proposed by NEC in 2001. To date, NEC has succeeded in synthesizing a polyradical of the modified PTMA, or “2,2,6,6-tetramethylpiperidinoxy-4-yl methacrylate,” with excellent durability. Due to the high reactivity and reversibility of the radical reaction, the organic radical battery demonstrates extremely high power density and good cycleability making it suitable for a range of next generation applications.