In Situ Flash Synthesis of Ultra-High-Performance Metal Oxide Anode through Shunting Current-Based Electrothermal Shock

The synthesis of anode materials plays an important role in determining the production efficiency, cost, and performance of lithium-ion batteries (LIBs). However, a low-cost, high-speed, scalable manufacturing process of the anode with the desired structural feature for practical technology adoption remains elusive. In this study, we propose a novel method called in situ flash shunt-electrothermal shock (SETS) which is controllable, fast, and energy-saving for synthesizing metal oxide-based materials. By using the example of direct electrothermal decomposition of ZIF-67 precursor loaded onto copper foil support, we achieve rapid (0.1-0.3 s) pyrolysis and generate porous hollow cubic structure material consisting of carbon-coated ultrasmall (10-15 nm) subcrystalline CoO/Co nanoparticles with controllable morphology. It was shown that CoO/Co@N-C exhibits prominent electrochemical performance with a high reversible capacity up to 1503.7 mA h g(-1) after 150 cycles at 0.2 A g(-1)and stable capacities up to 434.1 mA h g(-1) after 400 cycles at a high current density of 6 A g(-1). This fabrication technique integrates the synthesis of active materials and the formation of electrode sheets into one process, thus simplifying the preparation of electrodes. Due to the simplicity and scalability of this process, it can be envisaged to apply it to the synthesis of metal oxide-based materials and to achieve large-scale production in a nanomanufacturing process.