Bipolar Conjugated Microporous Polymer with Intrinsically Fast Reaction Kinetics for High-Energy-Density and High-Rate-Capacity Symmetric All-Organic Lithium-Ion Battery

Abstract

The development of high-performance symmetric all-organic batteries (SAOBs) is of great significance for next-generation environmentally friendly energy storage systems with high energy and power densities. Herein, we report a bipolar conjugated microporous polymer (CMP), named as PTTA that synthesized by integrating p-type Tris(4-formylphenyl)amine and n-type 2,7-diaminopyrene-4,5,9,10-tetraone. It features with unique donor-acceptor (D−A) structure, hierarchical porosity, abundant redox-active sites, and chemical stability, which collectively endow PTTA with intrinsically fast electrochemical reaction kinetics. As a cathode, PTTA delivers a high specific capacity of 353 and 140 mAh g–1 at 0.1 and 10 A g–1, respectively, with 91% capacity retention after 2000 cycles at 5 A g–1. As an anode, it achieves a high specific capacity of 1789 mAh g–1 at 0.1 A g–1. A PTTA-based SAOB (PTTA/PP/PTTA) in coin cells provides 257 mAh g–1 at 1.0 C and 148 mAh g–1 at 67.9 C. Moreover, a high-loading pouch-type device maintains high electrochemical performance and reaches 277 Wh kg–1. This demonstrates device-level feasibility and highlights the benefits of the D–A molecular design and hierarchical porosity in facilitating efficient bipolar redox reactions and fast charge storage. This work provides a valuable insight into the structure-function design principle of porous polymer for high-performance SAOB electrodes.