Solar‐responsive battery holds great promise in solar‐to‐electrochemical energy storage, but is impeded by the lack of efficient photoelectrochemical‐cathodes. Herein, a crystalline mesoporous (≈4.0 nm) covalent organic framework (TA‐PT COF) with repeating units consisting of covalently linked triphenylamine (TPA) and perylenetetracarboxylic diimide (PTCDI) is presented. The repeating unit functions as both a donor–acceptor pair and a dual‐redox site to realize a molecule‐level coupling of intramolecular charge separation (τCS = 136.2 ps, τCR = 949 ps) and reversible redox chemistry (C=O/CO−, TPA/TPA+). Equipped with this photoelectrochemical cathode, a reversible aqueous solar‐responsive battery delivered a reliable voltage‐response of 376 mV, an extra round‐trip efficiency of 35% and a good light durability (500 cycles). A photo‐coupled electron/mass transfer mechanism of photoelectrons for Zn2+ storage and holes for OTf− storage is further revealed, shedding light on a new photoelectrochemical cathode design based on charge separation and redox‐coupled COF for efficient solar‐responsive batteries.