|Thin Films and Nano Products|
nGimat is developing and commercializing a cost-effective manufacturing process for producing materials and components for battery and fuel cell applications. This is achieved using the proprietary NanoSpraySM Combustion Processing technology. These engineered nanomaterials will serve as building blocks for catalytic components and electrolyte and electrode components used in low-cost, high energy density batteries, solid oxide fuel cells (SOFC), and the membrane electrode assembly (MEA) in proton exchange membrane (PEM) fuel cells.
In early 2004, nGimat announced successful demonstration of its NanoSpray Combustion Processing technology for production of battery materials. nGimat, which uses its flame-based process to produce ceramic and metal nanomaterials, is developing nanomaterial solutions for primary and secondary lithium battery applications.
By nanoengineering the electrode, nGimat is forging the path to improved battery performance at lower costs. This approach promises both improved thick layers for active primary cell applications and mechanically robust thin layers with improved porosity for reserve batteries. The NanoSpray-based technology is attractive because it can be used to attain optimum performance morphology while remaining a continuous, high-throughput process for production of cathode composite layers.
The graph below shows cycling stability data comparing micron-sized LiNixCo1-xO2 to nGimat's corresponding nanomaterial. After some first cycle loss, nGimat's material has excellent charge capacity retention beyond cycle 2 while the micron-sized active material has catastrophic fade after just four cycles.
nGimat provides advanced materials and processes for fabrication of reliable SOFCs that can operate with regular fuels at reduced operating temperature and significantly reduced cost. Low-cost fabrication of high-quality SOFC electrolyte layers without complex post-deposition treatments or sintering is essential for their widespread commercialization. Additionally, new components are needed to meet the required operating temperature requirements. To lower operating temperatures, an alternative electrolyte with higher oxygen conductivity than yttria-stabilized zirconia (YSZ) must be used. Furthermore, electrodes currently used in SOFC applications require ultra-clean fuel for reliable operation because they are not sulfur tolerant, which further increases their cost. nGimat is developing new materials and refining the NanoSpray Combustion Processing technology for production of SOFC electrolytes. The company is also depositing electrode materials using the CCVD process to complete fuel cell component fabrication. Successful development will result in a low-cost fuel cell technology that will potentially achieve at least three times greater fuel economy than conventional sources of energy (i.e., fossil fuels) with significantly reduced emissions. nGimat's samaria-doped ceria (SDC) electrolytes can achieve comparable conductivities when run at 700 íC as YSZ does at 1000 °C. Some of the benefits of a reduced operating temperature include: better thermal integration with fuel reformers and sulfur removal systems, reduced material issues such as less thermal stress and more material flexibility, lower heat loss, shorter time to achieve operation temperature, and less corrosion. Support for SOFC material efforts is currently coming mostly from government contracts and commercial sales of nanopowders.
Proton Exchange Membrane (PEM) Fuel Cells
Processes and materials are being developed that will enable production of an MEA with reduced precious metal loading. This will enable lower cost and continuous production of MEAs in a one-step process. One of the most compelling features of nGimat's fabrication process is the flexibility and compatibility in working with various gas diffusion layers (GDL) and membranes for significant performance improvement and cost savings. nGimat's process dynamically combines the two-step production of the supported catalyst and the fabrication of the electrocatalyst layer into a one-step process. The "structure" for electrocatalyst layer can be formed in the deposition stream gas prior to depositing onto GDL or membrane substrates. The process does not require post-deposition treatment. Hence, the process can work with a broad range of substrates and ionomers.