High energy density carbon–cement supercapacitors for architectural energy storage
Significance As the world transitions from fossil fuels to a renewable energy-based economy, scalable, safe, and sustainable energy storage becomes essential to balance intermittent supply and demand. To address these needs, electron-conducting carbon concrete (ecˆ3) has emerged as a promising multifunctional material that unites structural performance with electrochemical energy storage, but its application has remained limited by low voltage and scalability challenges. Through nanoscale 3D imaging, electrolyte optimization, and multicell stacking, we demonstrate the production of high-voltage, energy-storing concrete components capable of powering devices and supporting mechanical loads. Our approach bridges architecture and energy systems, advancing ecˆ3 as a transformative material system for decarbonizing construction and enabling resilient infrastructure in the era of clean energy.