Ethoxycarbonyl-Based Organic Electrode for Li-Batteries

Currently, batteries are being both considered and utilized in a variety of large-scale applications. Materials sustainability stands as a key issue for future generations of batteries. One alternative to the use of a finite supply of mined materials is the use of renewable organic materials. However, before addressing issues regarding the sustainability of a given organic electrode, fundamental questions relating to the structure−function relationships between organic components and battery performance must first be explored. Herein we report the synthesis, characterization, and device performance of an organic salt, lithium 2,6-bis(ethoxycarbonyl)-3,7-dioxo-3,7-dihydro-s-indacene-1,5-bis(olate), capable of reversibly intercalating with minimal polarization 1.8 Li per unit formula over two main voltage plateaus located at ∼1.96 and ∼1.67 V (vs. Li/Li+), leading to an overall capacity of 125 mAh/g. Proton NMR and in situ XRD analyses of battery cycling versus Li at room temperature reveal that the insertion−deinsertion process is fully reversible with the dips in the voltage−composition traces, which are associated with changes in the 3D structural packing of the electrochemically active molecules.