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The potential advantages of lithium metal anodes have received widespread attention (highest capacity, lowest reduction potential, etc). However, the poor stability of Li metal / liquid electrolyte interfaces leads to chronic problems, such as dendrite formation and capacity loss. The possible impact of mechanical effects on interface stability and dendrite formation are difficult to probe directly. In this study, stress evolution during lithium plating and stripping was monitored with precise in situ measurements. The data obtained with different film thicknesses made it possible to separate the stresses associated with the lithium metal and the solid electrolyte interphase (SEI). The results show that significant stresses are created in the SEI films. Based on this, a basic model of wrinkling-ratcheting-delamination is also presented. This analysis indicates that plasticity in a growing Li film can enhance surface wrinkling, and thus lead to morphological destabilization of a planar growth front.

The potential advantages of lithium (Li) metal anodes have been widely touted (lowest reduction potential, etc.). However, the poor stability of Li metal / liquid electrolyte interfaces leads to chronic problems, such as dendrite formation and capacity loss. The possible impact of mechanical effects on interface stability and dendrite formation is a critical question that is difficult to probe directly. In-situ curvature measurements are an important tool for monitoring stresses during battery cycling. Using this technique during Li plating and examining film thickness effects, it is possible to separate contributions from the bulk lithium metal and the solid electrolyte interphase (SEI). These investigations show that significant stresses are created in the SEI films. Similar stress evolution measurements were also performed during lithium plating and stripping using both soft (PEO) and hard (LiF) artificial surface layers. The results indicate that stresses in surface films can be tuned to improve performance when artificial SEI layers are employed. A basic chemo-mechanical model indicates that hybridizing the two layers may benefit interface stability and performance in Li metal anodes.

This chapter aims at exploring the revolutionary field of nanotechnology and some of its promising aspects in polymer nanocomposites in view of preparation, characterization, materials properties, and processing of polymer layered silicate nanocomposites. These materials are attracting considerable interest in polymer science research. Polymer layered silicate nanocomposites are an important class of hybrid, organic/inorganic materials with substantially improved mechanical, thermal, and thermomechanical properties in comparison to pristine polymers. In addition, they also show superior ultraviolet (UV) as well as chemical resistance and are widely being investigated for improving gas barrier and flame retardant properties. Hectorite and montmorillonite are among the most commonly used smectite-type layered silicates for the preparation of polymer–clay nanocomposites. Smectites are a valuable mineral class for industrial applications due to their high cation exchange capacities, surface area, surface reactivity, adsorptive properties, and, in the case of hectorite, high viscosity and transparency in solution. A wide range of polymer matrices are explored for the preparation of polymer–clay nanocomposites, however, this chapter deals with special emphasis on biodegradable polymers––cellulose and natural rubber. Also, the chapter describes the common synthetic techniques in producing polymeric layered silicate nanocomposites, its properties, and applications.