The First Flexible Dual-Ion Microbattery Demonstrates Superior Capacity and Ultrahigh Energy Density: Small and Powerful

Humans live today in a high-tech and informationalized society. With the development of the emerging electronic information age, various electronic systems are inclined to be multifunctional and miniaturized. It is urgent to develop “small and powerful” micro-batteries with flexibility and high electrochemical performance to meet the diverse needs of microelectronic components. However, low electrochemical performance exists in traditional microenergy storage devices, which fail to satisfy the energy needs for microdevices. Here, for the first time, a planar integrated flexible rechargeable dual-ion microbattery (DIMB) is reported, which is fabricated from an interdigital pattern of graphite as an electrode and lithium hexafluorophosphate as an electrolyte. As a microbattery, the DIMB exhibits a high reversible capacity of 56.50 mAh cm⁻³, and excellent cycle stability with 90% capacity retention after 300 cycles under a high working voltage. The application of DIMB in microdevices, such as light-emitting diodes (LEDs), digital electronic game consoles, and electrochromic glasses is also investigated, fully demonstrating its “small and powerful” performance. The integrated DIMB is a high-voltage microdevice that reaches a nonpareil discharge voltage of about 100 V and a charging capacity of 102 mAh g⁻¹. This dual ion-based flexible microbattery could become a promising candidate for energy storage and conversion components in next-generation microelectronic devices and integrated electronic devices.