Drop-on-demand 3D-printed silicon-based anodes for lithium-ion batteries

We present the application of drop-on-demand (DoD) dispensing technology for printing of silicon-based anodes. We show that the DoD printing technique is highly suitable for printing of arbitrary-geometry, high-activity SiNi nanoparticle anodes for Li-ion batteries. These anodes are on par with traditionally prepared anodes in terms of electrochemical behavior and performance and can be easily used in printed or any other type of Li-ion cells. We found that improved adhesion is necessary because of the complex geometry of printed anodes. High adhesion was achieved with the use of two types of CNT coatings on the copper current collector, and etching of the copper itself without the use of an intermediate coating. Printed anodes are electrochemically stable and perform according to most criteria as well as previously presented cast anodes, exhibiting high capacity (500–1200 mAh/g anode, depending on the type of cell) and have a relatively long cycle life (up to 500 cycles). Our results highlight novel strategies for 3D electrode printing, for potential uses in specialized batteries, and are of particular importance for advanced research and development. Printed electrodes shown here can be directly implemented as described, or be used as reference for the development of new types of electrodes for energy storage devices.