Acupuncture‐Inspired Active‐Material Microenvironment Engineering for High‐Throughput Thick Electrodes by Instant Microneedle Templating

Abstract Rational design and ultrafast fabrication of high‐throughput thick electrodes are essential for high‐energy and power density batteries. However, it is blocked by the lack of both theory and cost‐effective technologies for regulating the active‐material microenvironment (AMME) that fundamentally controls the ion and electron transport for each active‐material particle. Here, inspired by the Chinese‐acupuncture therapy that employs microneedles to dredge the cell microenvironment, a microneedle‐array templated extrusion (MATE) technology is proposed along with an AMME‐therapy theory to address the above challenges. Specifically, a unique clay‐alike thixotropic (CAT) slurry through sol‐binder is first fabricated with significant capabilities in 3D‐morphing. Enabled by this morphable CAT‐slurry, MATE technology is further developed to rapidly and seamlessly fabricate high‐throughput 3D thick electrodes with customizable ordered ion‐transport channels. Consequently, the optimized 3D thick electrode shows a remarkable improvement in specific capacity by 300% even at an ultrahigh active‐material loading of 60 mg cm −2 (ca. 3 times the commercial level). Finally, an AMME therapy theory based on an artificial potential field algorithm for ion‐transport path optimization is established to understand the enhanced ion‐transport dynamics. The proposed AMME‐therapy theory and industry‐friendly MATE technology could advance the design and fabrication of high‐throughput electrodes in batteries and other electrochemical energy‐storage devices.