S. Wang, S.H. Zheng, X.Y. Shi, P. Das, L.M. Li, Y.Y. Zhu, Y. Lu *, X.L. Feng * and Z.-S. Wu *

Nature Communications, 2024, Accepted.

Precise separation and localization of tiny electrolyte on microcell arrays with an ultrasmall area and close-proximity is a huge roadblock, which hinders the densification of monolithically integrated micro-supercapacitors (MIMSCs). To overcome this grand challenge, we demonstrate a controllable electrolyte directed assembly strategy for precise isolation of densely-packed micro-supercapacitors (MSCs) at micron scale, achieving scalable production of MIMSCs with ultrahigh areal number density and output voltage. We fabricate a patterned heterogeneous adhesive surface across MIMSCs, that induce electrolyte directed assembly on 10000 highly adhesive MSC regions, achieving a 100 µm-scale spatial separation between each electrolyte droplet within seconds. The resultant MIMSCs achieve a areal number density of 210 cells cm-2 and an high areal voltage of 555 V cm-2. Further, cycling the MIMSCs at 190 V over 9000 times manifests no performance degradation. A seamlessly integrated system of ultracompact wirelessly-chargeable MIMSCs is also demonstrated to show its practicality and versatile applicability.