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Technology Transfer

RECENT RELEASES

The Lawrence Berkeley National Laboratory (Berkeley Lab) Technology Transfer Department licenses a wide range of cutting-edge technologies to companies that have the financial, R&D, manufacturing, marketing, and managerial capabilities to successfully commercialize Lab inventions. The Technology Transfer Department develops and manages an array of partnerships with the private sector. These technologies were developed by researchers in (or associated with) the Environmental Energy Technologies Division.

Dry Polymer Electrolytes with High Conductivity for Secondary Lithium Metal Batteries

Nitash Balsara and his research team have developed a dry polymer electrolyte that may remove a significant barrier to the development of reliable, secondary lithium metal batteries. The electrolyte has a high elastic modulus (~0.1 GPa), which should deter the dendrite formation that has hampered lithium metal battery development in the past, while still demonstrating high conductivity (~10 -3 S/cm at 85°C), a necessity if the high energy density potential of these batteries is going to be fulfilled. The Berkeley Lab electrolyte has been cycled with lithium metal electrodes over 80 times at 50% limiting current and 85°C with no evidence of dendrite formation.

The Berkeley Lab invention is a diblock, copolymer electrolyte consisting of soft, nanoscale, ionically conducting channels embedded in a major phase, hard nonconducting matrix. The properties of this system have been tested using a series of diblock copolymers with varying polystyrene (PS)/polyethyleneoxide (PEO) molecular weights and volume fractions. The conductivity of the Berkeley Lab PS-PEO copolymer is only a factor of two lower than that of bulk PEO. In addition, since the electrolyte is a dry polymer, it can be fabricated into an ultra thin layer to optimize conductivity. Research on this aspect of the technology is ongoing.

Many lithium metal battery technologies currently in development require a separation layer to isolate the anode from liquid electrolytes. The Berkeley Lab electrolyte serves both as an ion conductor and a dielectric separator between the electrodes, making these layers unnecessary and thereby avoiding additional interfacial resistance and promising simpler battery design and construction.

This technology is available for licensing or collaborative research.

For more information, contact:

  • Technology Transfer Department
  • Lawrence Berkeley National Laboratory
  • MS 90-1070
  • Berkeley, CA 94720
  • (510) 486-6467; Fax: (510) 486-6457

Air-stable Nanomaterials for Efficient OLEDs and Solar Cells

The Technology Transfer Department recently released two promising inventions from the Environmental Energy Technology and Materials Sciences division scientists for licensing.

Berkeley Lab researchers have developed two approaches for increasing the charge efficiencies of electrodes used to produce flexible organic light emitting diodes (OLEDs) and solar cells. Both approaches will reduce manufacturing and packaging costs. These technologies have patents pending and are available for licensing or collaborative research.

Solvent Processed Nanotube Composites

IB-2044

Applications

Composites for transparent electrodes and/or light emitting layers used in

  • OLED displays for consumer electronics, digital video, and medical imaging devices, or built into architectural and automobile windows and flexible plastics
  • Organic photovoltaics
  • OLEDs for lighting

Advantages

  • Solvent processed, ink jet printable
  • More efficient charge injection and higher conductivity than conventional conducting polymers
  • Transparent (= ITO film)
  • Reduced drive voltage
  • Compatible with flexible substrates
  • Longer material lifetimes than devices made with active metals

Description

A new class of conductive polymers developed at Berkeley Lab uniformly suspends and disperses carbon nanotubes, enabling them to function efficiently as charge injectors in the electrodes and light emitting layers of OLEDs and organic solar cells. Currently, OLEDs cathodes are thermal vacuum evaporated due to the use of reactive metals for electron injection. The use of calcium or lithium also requires air-impenetrable packaging. In contrast, devices made using Berkeley Lab's air-stable cathode materials can be solvent processed and applied using ink jet printing or spin coating. They also have relaxed packaging requirements.

Unlike most OLEDs that incorporate metals in the cathode, the Berkeley Lab OLEDs are transparent. Transparent OLEDs can be used to display video, images, and other information in applications where the user still can see through the substrate, such as with windshields and windows. While ITO films are also transparent, they are brittle and require plasma deposition. The Berkeley Lab materials are flexible and promise to be low-cost - making inexpensive, roll-up, digital display technology a near-future possibility.

Lab scientists have demonstrated initial efficiencies of three percent for OLED devices incorporating the poly(di(oxytrio xadecane)fluorine)(PFO)/nanotube composites, with a clear research path towards significant increases. The nanotubes have remained suspended in the PFO for over four months, far exceeding the six day limit achieved in other nanotube/ polymer systems. The suspension is sustainable because the polymer is amphiphilic and wraps its polar side chains around the nanotube. Both the backbone and side chains of the polymer can be adapted to accommodate various applications. This technology was invented by Stephen Johnson, John Kerr, Gao Liu, Sam Mao, and Andrew Minor.

OLEDs with Air-stable Structured Electrodes

IB-2231

Applications

  • OLED displays for consumer electronics, digital video, and medical imaging devices, or built into architectural and automobile windows and flexible plastics
  • Organic photovoltaics
  • OLEDs for lighting

Advantages

  • Enhanced charge injection efficiency and increase conductivity
  • Reduced drive voltage
  • Relaxed packaging and manufacturing requirements
  • Lithographically defined nanostructures
  • Longer material lifetimes than devices made with active metals
  • Can be applied to flexible substrates

Description

Stephen Johnson, Gao Liu, and Sam Mao have developed electrodes with nanostructured geometry to improve the electrical- optical energy conversion efficiency of flexible OLEDs and solar cells. The new transparent electrodes are less reactive to water and oxygen than their metal counterparts, which will reduce the costs of fabrication and packaging.

The researchers employ ordered arrangements of nanotubes or stable nanoclusters at the cathode-organic layer interface as charge injectors to efficiently overcome the large energy barrier at that interface. These structured electrodes promise to significantly reduce the drive voltage necessary to induce light emission inside organic materials and thereby increase the energy conversion efficiency of the resulting devices.

For more information, contact:

  • Technology Transfer Department
  • Lawrence Berkeley National Laboratory
  • MS 90-1070
  • Berkeley, CA 94720
  • (510) 486-6467; Fax: (510) 486-6457

More about Air-stable Nanomaterials for Efficient OLEDs and Solar Cells

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