Cross-linking Effects on Performance Metrics of Phenazine-Based Polymer Cathodes

Developing cathodes that can support high charge-discharge rates would improve the power density of lithium-ion batteries. Herein, the development of high-power cathodes without sacrificing energy density is reported. N,N'-diphenylphenazine was identified as a promising charge-storage center by electrochemical studies due to its reversible, fast electron transfer at high potentials. By incorporating the phenazine redox units in a cross-linked network, a high-capacity (223 mA h g^-1 ), high-voltage (3.45 V vs. Li/Li⁺ ) cathode material was achieved. Optimized cross-linked materials are able to deliver reversible capacities as high as 220 mA h g^-1 at 120 C with minimal degradation over 1000 cycles. The work presented herein highlights the fast ionic transport and rate capabilities of amorphous organic materials and demonstrates their potential as materials with high energy and power density for next-generation electrical energy-storage technologies.