A Sub‐Square‐Millimeter Microbattery with Milliampere‐Hour‐Level Footprint Capacity

As substantial progress has been made to miniaturize intelligent microsystems the sub-square-millimeter scale, there is a desperate need move beyond existing microbattery technologies offer adequate energy at same footprint. A micro-origami technology able wind up flat layer stack into Swiss roll presents promising approach in this regard because it mimics most successful way make energy-dense full-sized batteries. Here, an on-chip Swiss-roll current collector via process developed and infused with MnO2 slurry comprising zincophilic binder. The binder enhances zinc ion transportability suppresses dissolution. microelectrode used create small electrode footprint area of 0.75 mm2, which shows capacity 3.3 mAh cm–2. demonstrates reversible more than 1 cm–2 for 150 cycles. battery stability can be improved over 600 cycles 50% depth discharge. An integration microsystem demonstrated. microbatteries set foot untrodden providing ever miniaturized microsystems.