Pairing Cross-Linked Polyviologen with Aromatic Amine Host Structure for Anion Shuttle Rechargeable Batteries

Electroactive organic compounds could bring new chemical opportunities to further improve existing electrochemical energy-storage technologies as they can be prepared from less-limited resources and potentially at low environmental footprint. Among the current explored research fields, the anion-ion cell configuration appears poorly investigated although quite promising to promote the fabrication of molecular (metal-free) rechargeable batteries. Herein, we report the synthesis and the electrochemical behavior of both Mg/Li salts of 2,5-(dianilino)terephthalate (MgDAnT and Li₂ DAnT) and cross-linked polyviologen (c-PV²⁺ ) that can reversibly uptake/extract anions at different working potentials, enabling the assembly of full anionic organic batteries. The reversible anion ingress in MgDAnT is however accompanied by solvent co-insertion from the electrolyte that provokes an overpotential effect during the first charge. Full anionic batteries pairing Li₂ DAnT with c-PV²⁺ were assembled giving rise to 0.7 V as output voltage with a specific capacity of 50 mAh per gram of Li₂ DAnT.