PROPULSION AND POWER RAPID RESPONSE RESEARCH AND DEVELOPMENT (R&D) SUPPORT. Deliver Order 0002: Power-Dense, Solid Oxide Fuel Cell Systems: High- Performance, High-Power-Density Solid Oxide Fuel Cells - Materials and Load Control

摘要

High-Performance, High-Power-Density Solid Oxide Fuel Cells: Materials - Solid oxide fuel cell electrodes based on catalyst coatings offer substantial potential for creating more effective anode and cathode structures. Infiltrated anodes based on nickel metal can yield finer catalyst phase distribution at volumetric concentrations well below percolation for traditional cermets. The coarsening of nickel after high temperature thermal treatment poses substantial degradation to the deposited structure; therefore, methods of anchoring the nickel metal to the YSZ scaffold have been evaluated to stabilize fine scale electro-catalyst particles. Aluminum titanate was introduced into the porous YSZ anode scaffold to facilitate a step-wise chemical reaction to anchor the nickel metal catalyst. SEM observation of thermally treated nickel infiltrated scaffolds indicates excellent preservation of the nickel network at 800 degrees C for 100 hours. Electrochemical tests show not only decreased degradation rates, but also increased initial performance levels due to the additive. High Performance, High-Power-Density Solid Oxide Fuel Cells: Load Control - With currently foreseeable technology, a fuel cell stack capable of supplying the dynamic power requirements for turns, climb, and sprint maneuvers is so heavy as to negate the advantage of using a fuel cell in level flight. This essentially requires the hybridization of the fuel cell using a zero-average power source such as a battery or capacitor. In this report, we discuss the development of an extremely simple hybrid controller that combines the current/voltage characteristics of a battery and fuel cell. This controller could be readily adapted to current fuel cell powered vehicles.