The second research area is the study of nanostructured electrodes for energy storage and conversion. The group has two avenues for the synthesis of electrodes for energy storage: those based on SiNWs and composites with CNT fibres (Figure 2). The group has demonstrated a scalable method to fabricate Li-ion battery anodes that eliminates all solvents and mixing steps. This has the potential to reduce cost and avoid emissions in LIB cell manufacture of the order of 48kg CO2/kWh, or equivalent to around 2 tonnes of CO2 per electric vehicle. The anodes have > 75wt.% Si and high-performance properties. Their networks structure enables reaching high areal capacity (> 9mAh/cm2), and under repeated cycling prevents pulverisation and preserves electronic conductivity. The anodes are thus strong candidates for the next generation (3b, 4a) LIBs.
The second type are CNT fibres are used as scaffolds for composite electrodes produced by textile-like methods and leading to built-in current collectors that eliminate binders and low added-value carbons (LAVCs). The group has spent the last ca 5 years developing synthetic routes to grow active materials in the internal pores of CNT fibres, studying their complex structure, and performing extensive electrochemical studies to establish a clearer nexus between 3D structure, transport properties, mechanical properties and electrode performance.
Figure 2. Examples of nanostructured materials studies as electrodes for energy storage.
Selected references
Moumita Rana, Afshin Pendashteh, Richard S. Schäufele, Joaquim Gispert, Juan J. Vilatela – Eliminating Solvents and Polymers in High-Performance Si Anodes by Gas-Phase Assembly of Nanowire Fabrics. Adv. Energ. Mater. 2022. DOI: 10.1002/aenm.202103469
Nicola Boaretto, Moumita Rana, Rebeca Marcilla, and Juan Jose Vilatela – Revealing the Mechanism of Electrochemical Lithiation of Carbon Nanotube Fibers. ACS Applied Energy Materials 3 (9), 8695-8705, 2020. DOI: 10.1021/acsaem.0c01267
Moumita Rana, Nicola Boaretto, Anastasiia Mikhalchan, Maria Vila Santos, Rebeca Marcilla, and Juan Jose Vilatela – Composite Fabrics of Conformal MoS2 Grown on CNT Fibers: Tough Battery Anodes without Metals or Binders. ACS Applied Energy Materials 4, 6, 5668-5676, 2021. DOI: 10.1021/acsaem.1c00482