钾离子电池聚合物正极:储能机制与优化策略OA

Polymer cathodes have attracted growing interest for potassium-ion batteries(PIBs)due to their tunable molecular structures,abundant redox-active sites,and sustainable elemental compositions.Compared with inorganic intercalation-type cathodes,polymer cathodes typically store charge through reversible redox reactions between K+ions or electrolyte anions and organic functional groups,including carbonyl,imide,quinone,azo,imine,and nitrogen-containing heterocyclic units.Their electrochemical performance is governed not only by the intrinsic redox chemistry of the active sites,but also by the polymer backbone configuration,π-conjugation degree,aggregation behavior,pore structure,and the stability of the electrode/electrolyte interface.This review summarizes recent progress in polymer cathodes for PIBs,with a focus on potassium-storage mechanisms and structural optimization strategies.Representative mechanisms,such as carbonyl coordination,imide chelation,multielectron redox processes,bipolar charge compensation,and pseudocapacitive behavior,are discussed from the perspectives of molecular structure,ion-electrode interactions,and charge-transfer kinetics.In addition,the ion-specific differences among K+,Li+,and Na+are analyzed in terms of solvation/desolvation behavior,local coordination environments,and redox-site utilization.Key optimization strategies,including polymerization-degree control,rigid π-conjugated backbone design,porous or three-dimensional network construction,conductive compositing,and electrolyte matching,are highlighted.Finally,the remaining challenges and future research directions are discussed to guide the rational design of high-performance polymer cathodes for PIBs.