p-d Conjugated coordination polymers (CCPs) have attracted muchattention for various applications,although the chemical states and structures of many CCPs are still blurry. Now,aone-dimensional (1D) p-d conjugated coordination polymer for high performance sodium-ion batteries is presented. The chemical states of the obtained coordination polymer are clearly revealed. The electrochemical process undergoes at hree-electron reaction and the structure transforms from C=Nd ouble bonds and Ni II to CÀNs ingle bonds and Ni I ,r espectively.Our unintentional experiments provided visual confirmation of Ni I .T he existence of Ni I was further corroborated by its X-raya bsorption near-edge structure (XANES) and its catalytic activity in Negishi cross-coupling.Supportinginformation and the ORCID identification number(s) for the author(s) of this article can be found under: https://doi.

The oxidation of π–d‐conjugated coordination polymers (CCPs) accompanied with anion insertion has the merits of increasing the capacity and elevating the discharge voltages. However, previous reports on this mechanism either required more investigations or showed low capacity and poor cyclablity. Herein, triphenylene‐catecholate‐based two‐dimensional CCPs are constructed by employing inactive transition‐metal ions (Zn2+) as nodes, forming Zn‐HHTP. Substantial characterizations and theoretical calculations indicate the successive storage of cations and anions by redox reactions of only ligands, leading to a high reversible capacity of ≈150 mAh g−1 at 100 mA g−1 and a remarkable capacity retention of 90 % after 1000 cycles. On the contrary, as a control experiment, the analogous CCPs (Cu‐HHTP) with Cu2+ nodes, where both ligands and metal ions undergo redox reactions, accompanied by the storage of only Na+ cations, show a much poorer cyclability. These results highlight the importance of redox reactions of only ligands for long‐term cycle life and the insight into the storage mechanisms deepens our understanding on CCPs for the further design of CCPs with high performance.

The progress and challenges of the electrodes and electrolytes in organic potassium-ion batteries are summarized.