3-D Microfibrous Media Electrodes
Three-dimensional microfibrous media electrodes have enhanced mass and charge transport compared to traditional electrode structures, allowing electrochemical processes to be carried out at high-current densities with enhanced energy efficiency.
Microfibrous media was originally developed to provide enhanced performance for energy storage devices such as batteries, liquid-double layer capacitors, and fuel cells. The three-dimensional microfibrous-media based structure simultaneously minimizes mass- and charge-transfer resistances commonly encountered during high-current density operation of energy storage devices. This electrode structure is prepared utilizing IntraMicron's proprietary wet-lay, entrapment, and sintering processes, which provide structural stability and intimate contact between the electrochemically active phase and the charge-conducting microfibrous matrix. Depending on the specific electrochemical application, the electrode structure and its components can be tailored to provide optimal electrochemical performance.
The enhanced mass- and charge-transport properties of microfibrous media-based technologies enable the performance-limiting resistances during high-current density operation of energy storage devices to be overcome.
Microfibrous media-based electrode advantages
Improved Electron Transfer:
Metal microfibrous electrodes have electrical conductivities at least 100 times that of carbon-fiber-paper-based electrodes. For applications where a composite electrode structure is required, this enhanced conductivity is even realized in a three-dimensional structure, because IntraMicron's proprietary preparation methods promote enhanced contact between the electrochemically active phase and the sinter-welded charge carrier network.
Improved Mass Transfer:
Compared with traditional electrodes, microfibrous media-based electrodes are highly porous, having void fractions that range from 62% to 98%. The openness of this structure enhances the diffusion of components to and from the electrode surface. IntraMicron has the capability to tailor the structure of these electrodes to be effective for gas-phase, liquid-phase, and two-phase flow.
Improved Proton Transfer:
For polymer exchange membrane applications, efficient proton transfer is necessary in addition to efficient electron and mass transfer for optimal performance to be achieved. Proton conducting materials can easily be incorporated into the microfibrous electrode structure to provide a means for proton conduction even at distances far from the proton-conducting membrane allowing full utilization of the three-dimensional electrode structure. IntraMicron's proprietary electrode preparation process enables proton conducting materials to be efficiently incorporated into the electrode structure to achieve significant contact between the charge carrier, proton carrier, and electrocatalyst, resulting in reduced cell overpotential and increased efficiency.
Improved Energy Efficiency:
The three-dimensional MFEC electrode structure allows efficient conduction and mass transfer even during high-current-density operation. By decreasing the transport resistances associated with electrochemical process, cell overpotentials can be significantly lowered resulting in increased overall energy efficiency.