Moisture-driven Composite Battery from Waste Materials for Sustainable Energy Harvesting

Atmospheric moisture is an abundant, renewable resource with potential for sustainable energy harvesting. While moisture–material interactions can generate electricity under ambient conditions, most current systems remain expensive, specific environment dependent, and produce voltages too low for direct use in wearable electronics. To address these limitations, we developed a moisture-electric composite battery (MECB) from waste biomass and recycled materials that converts ambient humidity into continuous electrical output. The MECB integrates wild sugarcane fibers and recycled cigarette-butt cellulose with an upcycled carbon-paste layer, which enhances moisture uptake, ion dissociation, and directional ion migration across asymmetric current collectors. A single unit delivers up to 1.16 V and 16.44 µW cm⁻³, operates continuously in open environments, and self-restores voltage after drying via natural moisture reabsorption. A conceptual model establishes the moisture–electricity relationship, linking absorption to ion generation and power output. Scalable series/parallel configurations boost voltage and current, directly powering small electronics without external capacitors. This low-cost approach highlights moisture-activated textiles as sustainable, long-duration power sources for self-sufficient systems.