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Organic electrode materials offer unique opportunities to utilize ion-electrode interactions to develop diverse, versatile, and high-performing secondary batteries, particularly for applications requiring high power densities. However, a lack of well-defined structure–property relationships for redox-active organic materials restricts the advancement of the field. Herein, we investigate a family of diimide-based polymer materials with several charge-compensating ions (Li + , Na + , K + ) in order to systematically probe how redox-active moiety, ion, and polymer flexibility dictate their thermodynamic and kinetic properties. When favorable ion-electrode interactions are employed ( e.g. , soft K + anions with soft perylenediimide dianions), the resulting batteries demonstrate increased working potentials and improved cycling stabilities. Further, for all polymers examined herein, we demonstrate that K + accesses the highest percentage of redox-active groups due to its small solvation shell/energy. Through crown ether experiments, cyclic voltammetry, and activation energy measurements, we provide insights into the charge compensation mechanisms of three different polymer structures and rationalize these findings in terms of the differing degrees of improvements observed when cycling with K + . Critically, we find that the most flexible polymer enables access to the highest fraction of active sites due to the small activation energy barrier during charge/discharge. These results suggest that improved capacities may be accessible by employing more flexible structures. Overall, our in-depth structure–activity investigation demonstrates how variables such as polymer structure and cation can be used to optimize battery performance and enable the realization of novel battery chemistries. 

Modifying electrodes with silver nanoparticles is broadly enabling for electrochemical formation of carbon–carbon bonds. 

The increasing demands for high-power electrical energy storage technologies require the development of new electrode materials and architectures with fast ion and electron transport. Herein, we report a new family of ter-polymers as battery cathode materials which exhibit significantly improved performance over their parent co-polymers: poly(phenylene-phenazine), and poly(1,3,5-phenylene-phenazine). The high electronic conductivity of poly(phenylene-phenazine) and fast ionic transport of poly(1,3,5-phenylene-phenazine) are combined in this series of ter-polymers, exhibiting improved battery performances which are especially apparent at high rates. The optimized ter-polymer delivers 180 mA h g −1 when discharged at 16 A g −1 , demonstrating the effectiveness of balancing ionic and electronic transport properties.