7 research outputs found
Avoiding Dendrite Formation by Confining Lithium Deposition Underneath Li-Sn Coatings
The
use of interfacial layers to stabilize the lithium surface is a popular
research direction for improving the morphology of deposited lithium and
suppressing lithium dendrite formation. This work considers a different approach
to controlling dendrite formation where lithium is plated underneath an
interfacial coating. In the present research, a Li-Sn intermetallic was chosen
as a model system due to its lithium-rich intermetallic phases and high Li
diffusivity. These coatings also exhibit a
significantly higher Li exchange current than bare Li thus leading to better charge
transfer kinetics. The exchange current is instrumental
in determining whether lithium deposition occurs above or below the Li-Sn coating. High-resolution
transmission electron microscopy and cryogenic focused ion beam scanning
electron microscopy were used to identify the features associated with Li
deposition. Atomic scale simulations provide insight as to the adsorption
energies determining the deposition of lithium below the Li-Sn coating. </p
Evaluation of the ecological status of a stream in middle Tennessee using periphyton characteristics
Volume: 2015-65Start Page: 1End Page:
Recommended from our members
Operando calorimetry informs the origin of rapid rate performance in microwave-prepared TiNb2O7 electrodes
Operando Calorimetry Informs the Origin of Rapid Rate Performance in Microwave-Prepared TiNb2O7 Electrodes
The shear-phase compound TiNb2O7 has recently emerged as a safe and high-volumetric density replacement for graphite anodes in lithium ion batteries. An appealing feature of TiNb2O7 is that it retains capacity even at high cycling rates. Here we demonstrate that phase pure and crystalline TiNb2O7 can be rapidly prepared using a high-temperature microwave synthesis method. Studies of the charging and discharging of this material, including through operando calorimetry, permit key thermodynamic parameters to be revealed. The nature of heat generation is dominated by Joule heating, which sensitively changes as the conductivity of the electrode increases with increasing lithiation. The enthalpy of mixing, obtained from operando calorimetry, is found to be small across the different degrees of lithiation pointing to the high rate of lithium ion diffusion at the origin of rapid rate performance.</div
Recommended from our members