An increasing demand for electrochemical energy storage and conversion devices stimulates progress in research on electrode and electrolyte materials. In the field of electrodes materials, silicon is the one of the most promising anode materials for Li-ion batteries. However silicon has the drastic volume variation (around 3 times lower on extraction) during insertion and extraction of lithium ions. As an alternative, nanocomposites enabling compensation of this drastic volume changes are proposed. Among them are composites Si/C derived from SiO2/C material. Here we present our attempt to produce such nanocomposite. Material was prepared using silica aerogel as a matrix for preparation carbon nanomaterials. The morphology of the sample was determined using a scanning electron microscope (SEM). The chemical composition was determined by dispersive X-Ray detector attached to the SEM. Structure of the samples was measured by X-Ray diffraction, Raman spectroscopy and ATR-FTiR spectroscopy. The presence of silica proved by ATR-FTiR. The XRD pattern confirms that structure of our material is amorphous. Raman spectrum confirms presence of graphitized carbon as a well shaped D and G peaks were recorded. Prepared material was used as an electrode served as the working electrode Swagelok type testing cell. First stage was electrode formatting using potentiostatic polarizaton. We assumed that during electroreduction the chemical interaction between LixC and SiO2 may take place bringing about silicon. During following steps the composite electrodes have been tested using, electrochemical impedance spectroscopy, polarization techniques – chronopotentiometry and cyclic voltammetry.
Authors
Additional information
- Category
- Inne
- Type
- supllement, wydanie specjalne, dodatek
- Language
- angielski
- Publication year
- 2013
