Enhanced Electrochemical Processes
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.
Liquid Double-Layer Capacitors
Microfibrous media technology was first applied to achieve enhanced performance from liquid double layer capacitors. The energy density of liquid double-layer capacitors increases with active surface area presented to the electrolyte while power density is controlled and limited by the diffusion of the electrolyte through the electrode material. Since higher levels of surface area are typically achieved by using materials with smaller pore dimensions, diffusion resistances are often increased; therefore, it is difficult to simultaneously achieve high energy density and high power density. The unique combination of properties presented by microfibrous carbon-metal composite electrodes enables high carbon surface area and mass transport to be attained simultaneously in a three-dimensional electrode structure. The flexibility of the microfibrous media structure enables microfibrous media-based electrodes to be tailored to achieve specific electrochemical criteria.
Fuel Cell and Electrolysis Cell Electrodes
Fuel cells and electrolysis cells often suffer from significant mass and charge transfer resistances especially when operating at high current densities. These internal resistances result in high cell overpotentials and low-efficiency operation. Three-dimensional microfibrous media-based electrodes are capable of operating efficiently at high current densities because of their improved mass and electron transport properties.
Chlor-Alkali Cell Electrodes
The enhanced electrical conductivity, mass transport, and catalyst utilization of electrochemical cells results in enhanced performance in chlor-alkali cells. The optimized microfibrous electrodes have lower overpotential than proprietary commercial chlor-alkali electrodes. During the development of these electrodes a unique property of microfibrous media based electrodes was highlighted, increasing electrode thickness enhanced electrochemical performance. Typical electrode structures show decreased performance with increased thickness because of transport limitations; however, in the case of composite microfibrous electrodes, the opposite trend is observed: increasing thickness (to a certain point) results in enhanced electrochemical performance.
Air Cathodes for Batteries
The unique structure and properties of composite microfibrous media-based cathodes allows the production electrode structures that are thinner than those that are typically available. The tunability of the microfibrous media structure enables structural tuning to achieve the desired electrochemical properties.