Liquid-Locked Bassanites for Scalable Fabrication of High-Temperature Micro-Supercapacitors Working at 300 °C

Journal article, 2026

Many emerging industry applications demand electronic systems with reliable operation at temperatures >300 °C. To date, the most promising on-chip power sources, micro-supercapacitors (MSCs), can only operate at temperatures up to 250 °C for a short period as limited by the vulnerability of their electrolyte frameworks at high temperatures. Here, a strategy is proposed to use liquids to lock the phase transformations of bassanite microrods for scalable on-chip printing of interlocking ceramic frameworks with high thermal stability. The robust ceramic frameworks enable simple yet scalable fabrication of MSCs to work at 300 °C with an areal capacitance of up to >60 mF cm⁻² and only ≈3% performance degradation after 1000 cycles during a test period of ≈3 h. A large-scale MSC array, consisting of 20 cells within a footprint area of 4 cm × 8 cm, has been able to supply a power of 7.2 mW at 300 °C. These break through the present limit of 250 °C of almost all high-temperature energy storage devices and pave the way for on-chip MSCs for high-temperature electronics.