Multi-material 3D printing of Graphene-based electrodes for Electrochemical Energy Storage using Thermo-Responsive Inks
By Garc
Published in ACS Applied Materials & Interfaces
Abstract
The current lifestyles, increasing population and limited resources result in energy research being at the forefront of worldwide grand challenges, increasing the demand for sustainable and more efficient energy devices. In this context, Additive Manufacturing brings the possibility of making electrodes and electrical energy storage (EES) devices in any desired 3D shape and dimensions, while preserving the multifunctional properties of the active materials in terms of surface area and conductivity. This paves the way to optimized and more efficient designs for energy devices. Here we describe how three-dimensional (3D) printing will allow the fabrication of bespoke devices - with complex geometries, tailored to fit specific requirements and applications - by designing water-based thermo-responsive inks to 3D-print different materials in one step. For example, printing the active material precursor (Chemically Modified Graphene, rCMG) and the current collector (copper) for supercapacitors or anodes for Lithium-ion batteries (LIBs). The formulation of thermo responsive inks using Pluronic F127 provides an aqueous-based, robust, flexible and easy scalable-up approach. The devices are designed to provide low resistance interface, enhanced electrical properties, mechanical performance, packing of rCMG and low active material density while facilitating the post-processing of the multicomponent 3D printed structures. The electrode materials are selected to match post-processing conditions. The reduction of the active material (rCMG) and sintering of the current collector (Cu) take place simultaneously. The electrochemical performance of the rCMG-based self-standing binder-free electrode and the two-materials rCMG/Cu printed prove the potential of multi-material printing in energy applications.