Environmental concerns about carbon emissions are motivating development of Proton-Exchange Membrane Fuel Cell (PEM-FC) technology for automotive propulsion. Catalyst Coated Membranes (CCM), which are the electrochemical „heart‟ of PEM-FC, consist of a proton-conductive polymer membrane embedded between two porous, electron conductive electrodes. The catalyst in the cathode consists of Pt nanop...

Emission of gas at charged states of lithium ion batteries (LIBs) is a significant problem because it causes swelling and deformation of LIBs. In this study, the gas generation mechanism is investigated and preventative measures are developed. Decomposition of the electrolyte solution related to residual lithium compounds on the surface of LiNi0.5Co0.2Mn0.3O2 (NCM523) and to the structural chan...

Reported here is a battery in the form of a cement-matrix composite, with cement paste as the matrix, the pore solution in cement as the electrolyte, zinc particles dispersed in the matrix as the anode, manganese dioxide particles dispersed in the matrix as the cathode, and carbon black dispersed in the matrix as the conductive additive in both anode and cathode regions. The electrolyte is cont...

The electrochemical performance of lithium-oxygen (Li-O2) batteries can be markedly improved through designing the architecture of cathode electrodes with sufficient spaces to facilitate the diffusion of oxygen and accommodate the discharge products, and optimizing the cathode catalyst to promote the oxygen reduction reaction and oxygen evolution reaction (OER). Herein, we report the synthesis ...

Since the discovery of carbon nanotubes (CNTs), researches of field emission display (FED) have been mainly focused on it, because of their high-aspect configuration, low work function, high mechanical stability and high conductivity. For CNTs to become a viable engineering material for FED applications, efficient assembly and integration processes for large size are required that are currently...

Electron energy distribution functions (EEDF’s) are presented over a two-dimensional array of locations in the discharge chamber of a 40-cm diameter ring-cusp ion thruster. The EEDF’s are obtained using two different techniques illustrating comparable results. A distinct difference in the EEDF’s measured through the double layer potential gradient, which transitions between the low-potential di...

Water management is one issue that must be surpassed to ensure high membrane proton conductivity and adequate reactant transport in the membrane-electrode assembly (MEA) simultaneously. A well-designed water system based on a comprehensive understanding of inner part polymer electrolyte (PEM) fuel cell. In this work, phenomena MEA PEM cell are analyzed by using mathematical model. The diluted s...

Capacity and voltage fading of layered structured cathode based on lithium transition-metal oxide is closely related to the lattice position and migration behavior of the transition-metal ions. However, it is scarcely clear about the behavior of each of these transition-metal ions in this category of cathode material. We report direct atomic resolution visualization of interatomic layer mixing ...

Improving oxygen reduction in microbial fuel cell (MFC) cathodes requires a better understanding of the effects of the catalyst binder chemistry and properties on performance. A series of polystyrene-bpoly(ethylene oxide) (PS-b-PEO) polymers with systematically varying hydrophilicity were designed to determine the effect of the hydrophilic character of the binder on cathode performance. Increas...

Increasing lithium content is shown to be a successful strategy for designing new cathode materials. In layered Li(x)Ni(2-4x/3)Sb(x/3)O2 (x = 1.00-1.15), lithium excess improves both discharge capacity and capacity retention at 1C. Structural studies reveal a complex nanostructure pattern of Li-Sb and Ni-Sb ordering where the interface between these domains forms the correct local configuration...