Exclusive Solution Discharge in Li-O Batteries?

Capacity, rate performance, and cycle life of aprotic Li-O batteries critically depend on reversible electrodeposition of LiO. Current understanding states surface-adsorbed versus solvated LiO controls LiO growth as surface film or as large particles. Herein, we show that LiO forms across a wide range of electrolytes, carbons, and current densities as particles via solution-mediated LiO disproportionation, bringing into question the prevalence of any surface growth under practical conditions.

In situ small-angle X-ray scattering reveals solution phase discharge of Li-O batteries with weakly solvating electrolytes.

Electrodepositing insulating lithium peroxide (LiO) is the key process during discharge of aprotic Li-O batteries and determines rate, capacity, and reversibility. Current understanding states that the partition between surface adsorbed and dissolved lithium superoxide governs whether LiO grows as a conformal surface film or larger particles, leading to low or high capacities, respectively. However, better understanding governing factors for LiO packing density and capacity requires structural sensitive in situ metrologies.

Quantitative-phase-contrast imaging of a two-level surface described as a 2D linear filtering process.

The paper deals with quantitative phase imaging of two-height-level surface reliefs. The imaging is considered to be a linear system and, consequently, the Fourier transform of the image is the product of the Fourier transform of a 2D function characterizing the surface and a specific 2D coherent transfer function. The Fourier transform of functions specifying periodic surface reliefs is factorized into two functions similar to lattice and structure amplitudes in crystal structure analysis.

Combining confocal and BSE SEM imaging for bone block surfaces.

The present report presents a method for the correlation of qualitative and quantitative BSE SEM imaging with confocal scanning light microscopy (CSLM) imaging modes applied to bone samples embedded in PMMA. The SEM has a proper digital scan generator: we leave the BSE image unchanged, and match the CSLM image to it, because the CSLM scan mechanism is not digital, though the signal is digitised. Our overlapping program uses a linear transformation matrix which projects one system to the other, calculated by finding three corresponding points in BSE and CSLM pictures.