Fabrication of silicon microwires by a combination of chemical etching steps and their analysis as anode material in Li-ion batteries. (10th November 2019)

• Record Type: Journal Article
• Authors: Pérez-Díaz, Oscar; Quiroga-González, Enrique; Hansen, Sandra; Silva-González, Nicolás Rutilo; Carstensen, Jürgen; Adelung, Rainer
• Is Part Of: Materials technology. Volume 34:Number 13(2019)
• Page Start: 785
• Page End: 791
• Publication Date: 2019-11-10
• Subjects: Li ion battery -- Si microwires -- metal assisted chemical etching -- impedance spectroscopy -- mechanical stability; Materials -- Periodicals; Materials science -- Periodicals; Materials -- Technological innovations -- Periodicals; 620.1105
• DOI: 10.1080/10667857.2019.1629059
• Languages: English
• ISSNs: 1066-7857

Abstract

ABSTRACT: This work presents a thorough study of Si microwires obtained by a novel combination of chemical etching steps, for their application as anode material in Li-ion batteries. The fabrication process starts with standard photolithography followed by a metal-assisted chemical etching step and anisotropic etching. This process can be performed in any chemical laboratory. The final structures possess a diameter and a length of 1.5 and 24 µm, respectively. Paste electrodes were prepared using the Si microwires and were tested in half-battery cells. Cyclic voltammetry and impedance spectroscopy evidenced the formation of Li–Si alloys and a solid electrolyte interface. The lithiated wires are mechanically stable upon lithiation, even when they expand to the 256% of their original volume.