Fast-Charging Carbon Fiber Structural Battery Electrodes Using an Organic Polymer Active Material

Abstract

Structural batteries require electrodes with integrated energy storage and load-bearing properties. Adoption of structural batteries can lead to mass and volume savings in electrified transportation and aerospace applications by storing energy within the object’s structural elements. However, to date, active materials investigated in structural batteries exhibit poor rate capabilities at higher C-rates and even worse performance at lower temperatures due to diffusion limitations. Organic radical polymers are promising alternatives because they possess fast-charging properties and good cycling stability. In this work, we integrate an organic radical polymer with carbon fiber (CF) fabric, in which the polymer acts as the active cathode material and the CF fabric possesses excellent tensile strength, modulus and electronic conductivity. At 20°C, the structural cathodes exhibited a reversible capacity of 67 mAh g-1 at 1C-rate and an 88% capacity retention at 25C-rate. Further, these structural electrodes retained more than 50% of their performance at -10°C (versus 20°C). These electrodes were further examined in a full cell containing a graphite-based anode, demonstrating a pathway for utilizing redox-active polymer-based active materials in structural and fast-charging organic batteries.