Thickness Variation of Conductive Polymer Coatings on Si Anodes for the Improved Cycling Stability in Full Pouch Cells.

Si-dominant anodes for Li-ion batteries provide very high gravimetric and volumetric capacity but suffer from low cycling stability due to an unstable solid electrolyte interphase (SEI). In this work, we improved the cycling performance of Si/NCM pouch cells by coating the Si anodes with the conductive polymer poly(3,4-ethylenedioxythiophene) (PEDOT) prior to cell assembly via an electropolymerization process. The thicknesses of the PEDOT coatings could be adjusted by a facile process parameter variation.

The Optimal Amount of Lithium Difluorophosphate as an Additive for Si-Dominant Anodes in an Application-Oriented Setup.

Fluoroethylene carbonate (FEC) and vinylene carbonate (VC) are considered the most effective electrolyte additives for improving the solid electrolyte interphase (SEI) of Si-containing anodes while lithium difluorophosphate (LiDFP) is known to improve the interphases of cathode materials and graphite. Here, we combine VC, FEC, and different amounts of LiDFP in a highly-concentrated electrolyte to investigate the effect on Si-dominant anodes in detail. Cycle life tests, electrochemical impedance spectroscopy and rate tests with anode potential monitoring were conducted in Si/NCM pouch cells.

Influence of the Silicon-Carbon Interface on the Structure and Electrochemical Performance of a Phenolic Resin-Derived Si@C Core-Shell Nanocomposite-Based Anode.

Silicon is one of the most promising materials when it comes to lithium-ion battery anodes because of its high theoretical capacity and the low working potential Li/Li. However, the drastic volume change during lithiation and delithiation leads to a rapid failure of the electrode. In order to accommodate the large volume change, Si@C core-shell nanocomposites have been investigated, as they efficiently protect the Si surface from being exposed to the electrolyte and thus limit side reactions and improve the cycling stability through a stable solid electrolyte interface layer.

Towards a Greener and Scalable Synthesis of NaTiO Nanorods and Their Application as Anodes in Batteries for Grid-Level Energy Storage.

Grid applications require high power density (for frequency regulation, load leveling, and renewable energy integration), achievable by combining multiple batteries in a system without strict high capacity requirements. For these applications however, safety, cost efficiency, and the lifespan of electrode materials are crucial. Titanates, safe and longevous anode materials providing much lower energy density than graphite, are excellent candidates for this application.

Highly Porous Silicon Embedded in a Ceramic Matrix: A Stable High-Capacity Electrode for Li-Ion Batteries.

We demonstrate a cost-effective synthesis route that provides Si-based anode materials with capacities between 2000 and 3000 mAh·g (400 and 600 mAh·g), Coulombic efficiencies above 99.5%, and almost 100% capacity retention over more than 100 cycles. The Si-based composite is prepared from highly porous silicon (obtained by reduction of silica) by encapsulation in an organic carbon and polymer-derived silicon oxycarbide (C/SiOC) matrix.