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Conjugated coordination polymers (CCPs) with extended π–d conjugation, which can effectively promote long‐range delocalization of electrons and enhance conductivity, are superior to traditional metal‐organic frameworks (MOFs) and attracted great attention for potential applications in chemical sensors, electronics, energy conversion/storage devices, etc. However, the precise construction of CCPs is still challenging due to the complex and uncontrollable reactions of CCPs. Herein, two different framework dimensions of CCPs are controllably realized by employing the same ligand (2,3,5,6‐tetraaminobenzoquinone (TABQ)) and the same metal (copper) as center ions. The manipulation of reaction leads to different valences of ligands and metal ions, different coordination geometries, and thereby 1D‐CuTABQ and 2D‐CuTABQ frameworks, respectively. High performance of charge storage is hence achieved involving the storage of both cations and anions, and therein, 2D‐CuTABQ shows a high reversible capacity of ≈305 mAh g−1, good rate capability and high capacity retention (≈170 mAh g−1 after 2000 cycles at 5 A g−1 with 0.01% decay per cycle), which outperforms 1D‐CuTABQ and almost all of the reported MOFs as cathodes for batteries. These results highlight the delicate structural control of CCPs for high‐performance batteries and other various applications. [ABSTRACT FROM AUTHOR]

• The modification strategy with PDA@nano-TiO 2 was designed to enhance electrochemical performance of spinel LNMO. • PDA@TiO 2 -LNMO cathode showed high reversible capacities and good capacity retention. • The excellent performance was attributed to PDA@nano-TiO2 as protective layer and good conductor for Li+ diffusion. The surface modification of LiNi 0.5 Mn 1.5 O 4 cathode material with PDA@TiO 2 enable it gain the high reversible capacities and good capacity retention. [Display omitted] Improving the cycling performance without sacrificing its capacity is challenging for high-voltage LiNi 0.5 Mn 1.5 O 4 cathode due to the trade-off nature among the key properties. A self-polymerization process of dopamine was utilized to grow polydopamine (PDA)-nano titanium dioxide assembly. PDA@TiO 2 composite was demonstrated to be integrated with the particles of high-voltage spinel LiNi 0.5 Mn 1.5 O 4 cathodes via wet chemical method. PDA@TiO 2 decorated LNMO improved the long-term cycling performance and rate capability by suppressing detrimental side reactions in balancing the interfacial stability and Li+ diffusion kinetics of LNMO and consequently providing efficient conductive pathways. As a result, 2% PDA@TiO 2 modified LNMO cathode exhibited the high reversible capacity of 117 mAh g−1 after 1000 cycles with good capacity retention of 90.7% at 1 C, and superior rate capability (78.5 mAh g−1 at 5 C) at room temperature. Remarkably, a significant improvement in cycling stability at an elevated temperature (50 °C) was obtained for the PDA@TiO 2 -LNMO composite, giving a capacity retention of 93% after 100 cycles at 1 C. The mechanism of performance improvement could be attributed to the maintenance of the structural stability of LNMO cathode materials and the enhanced kinetics of the remarkable lithium-ion diffusion through the protective effect of PDA@TiO 2 decorating. [ABSTRACT FROM AUTHOR]