Intrinsically Stretchable Microbattery with Ultrahigh Deformability for Self-Powering Wearable Electronics

The advancements in stretchable electronics toward wearable applications require compatible power sources to form stand-alone systems. Stretchable microbatteries and microsupercapacitors are promising candidates due to their compact sizes, planar configurations, and versatile system integrations. The degraded electrochemical performances upon stretching unfortunately represent the major limitation for these miniaturized energy storage devices. Here, we present a scalable fabrication approach for an intrinsically stretchable Zn-MnO2 microbattery featuring excellent electrochemical performance and ultrahigh stretchability of up to 200%. As a key design concept, the interdigitated current collector harnesses heterogeneous stiffness to create spatially nonuniform strain distributions for selective reduction of actual strains on individual electrodes. The corresponding microbattery consequently achieves reliable operations under both static and dynamic tensile deformation modes. A self-powering system composed of an LED array powered by a microbattery pack achieves conformable attachment onto the moving body, which demonstrates the practical suitability of the microbattery for skin-attachable wearable electronics.