In this study, temperature-humidity-bias (THB) testing and water droplet (WD) testing have been conducted to study electro-chemical migration (ECM) and dendrite formation across features in aerosol jet printed (AJP) conductor patterns. Test specimen design and testing conditions were guided by industrial standards and related research studies. Time-to-failure (TTF) for AJP printed silver patterns is found to be much smaller than that for conventional copper patterns in THB testing, under identical testing conditions. Furthermore, TTF for dendrite growth between neighboring biased conductors at constant temperature and humidity conditions was found to have a non-monotonic dependence on the electric potential gradient. The dendrite density was found to vary significantly with different applied voltage gradients in both THB testing and WD testing. Those observations can help to guide future investigation and life-prediction modeling of AJP printed electronics subjected to combined temperature, humidity, and voltage stresses.

Sulfur-based silver corrosion product is fragile and can shed during handling. Special handling is needed to monitor the silver corrosion rate. This factor has implications for the accurate interpretation of corrosion tests. An updated handling procedure is discussed.

Mixed flowing gas (MFG) testing is used to demonstrate the ability of an electronic product or system to survive in a corrosive environment. MFG testing is designed to corrode copper and silver, which are often used as electrical conductors in electronic products. However, MFG tests have failed to identify issues in recent years. These failures have been predominately related to the corrosion of silver. To understand these test escapes, the corrosion of silver and copper corrosion under MFG is examined. For comparison, a flower of sulfur (FoS) test at 75°C was also conducted. The test results show that the rate of copper and silver corrosion is not equivalent but varies depending on the gas concentration, which explains the failure escapes.

Solid oxide fuel cells (SOFCs) are chemical-to-electrical energy conversion devices that consist of ceramic and metallic materials. The electrodes of SOFCs function as sites for electrochemical reactions, and as electronic conductors to transfer charge. The strontium-based perovskite electrode has been considered because it offers ionic and electronic conductivity, and tolerance to reduction-oxidation cycling. However, as shown in this work, exposure to humidity greater than 40% relative humidity, that may be present during non-operation conditions, including storage, can result in changes in the electrode surface composition with resulting degradation of electrical performance. This study investigates the physical-chemical and electrical characteristics of electrode surfaces when subjected to various humidity and temperature conditions, using scanning electron microscopy, energy dispersive spectroscopy, X-ray fluorescence spectroscopy, X-ray photoelectron spectroscopy, and X-ray diffraction techniques. Electrode phase decomposition, along with strontium-based degradation mechanisms, were found at humidity levels greater than 40% relative humidity.

Solid oxide fuel cells (SOFCs) are a highly efficient chemical to electrical energy conversion devices that have potential in a global energy strategy. The wide adoption of SOFCs is currently limited by cost and concerns about cell durability. Improved understanding of their degradation modes and mechanisms combined with reduction–oxidation stable anodes via all-ceramic-anode cell technology are expected to lead to durability improvements, while economies of scale for production will mitigate cost of commercialization. This paper presents an Ishikawa analysis and a failure modes, mechanisms, effects, and criticality analysis (FMMECA) for all-ceramic anode based SOFCs. FMMECA takes into account the life cycle conditions, multiple failure mechanisms, and their potential effects on fuel-cell health and safety.