Accelerating wound healing with flexible zinc ion microbatteries coupled with endogenous electrical fields

Wound healing is an important physiological process in living organisms, involving the migration and proliferation of cells in the endogenous electric field (EEF). Continuous and stable electrical stimulation by an external power supply can effectively mimic the EEF, accelerating the biological processes involved in wound healing. However, the clumsiness of conventional external power supplies and the unstable voltage output of novel power supplies greatly limit the application of electric fields for wound healing. Here we demonstrate the use of a flexible and wearable microbattery for wound healing. The annular electrode is designed to generate an annular electric field in the same direction as the EEF of the wound, allowing for faster, more uniform fibroblast migration, proliferation, and transdifferentiation processes, thus accelerating wound healing. Studies on rats show that skin wounds given a stable electric field using aqueous Zn-MnO2 microbatteries with an operating voltage of 1.5 V healed completely within 6 days, while the blank control group took 10 days or longer. Further, the series connection of microbatteries can match wounds of different areas, enabling rapid healing. These advantages make flexible microbatteries highly promising for practical applications in the biomedical field.