Y. Ma, S. Wang *, Z.B. Guo, X. Wang, Y.X. Ma, Y.H. Fu, H.Q. Liu, S.W. Li, Y. Lu *, Z.Z. Yuan and Z.-S. Wu *
National Science Review, 2025, accepted.

The burgeoning Internet of Things (IoT) demands highly customizable microbatteries (MBs) to power miniaturized electronics, yet challenges exist in fabricating ultrasmall MBs and integrating customizable modules within confined areas. Herein, we report a novel photolithographic microfabrication strategy enabling large-scale production of monolithic integrated ultrasmall MBs. The approach utilizes photoresist grooves as micropattern templates and employs a non-destructive mechanical peeling process to fabricate precise MBs with a compact area of 2.2275 mm2, using Li3V2(PO4)3 as both cathode and anode. These MBs demonstrate an exceptional areal capacity of 96.4 μAh cm−2 and remarkable cycling stability, retaining 88.3% of their initial capacity after 10 000 cycles. Furthermore, the method allows facile serial integration of numerous MBs in a single step, achieving a record voltage of 182.7 V through 63 series-connected units. This breakthrough provides a scalable solution for mass-producing customizable MBs, advancing the power supply capabilities for miniature electronics with high energy density and long-term reliability.