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Recently,energy storage and conversion technologies have attracted wide attention of researchers with the increasing demand for clean energy and the development of electric vehicles and smart grids.Lithium-ion battery is one of the mainstream electrochemical energy storage technologies in the market due to its excellent comprehensive performance.Redox-active organic cathode materials have been demonstrated to have critical advantages over the commercial inorganic cathode materials,such as low-cost,sustainability,diverse structure and outstanding electrochemical properties.However,the limited active sites,low output voltage and ambiguous charge storage mechanism are still the main obstacles to the development of organic cathode materials for lithium-ion batteries.In this paper,a series of organic electroactive compounds with multiple active centers based on tripyridine-triazine were prepared by molecular design,and their electrochemical performance and energy storage mechanism as cathode materials of lithium-ion batteries were studied.The main research contents and results are as follows:（1）Preparation of 2,4,6-tri（4-pyridyl）-1,3,5-triazine（TPT）molecules and its application as organic cathode material for lithium-ion batteries.The experimental results show that TPT-based organic cathode material can deliver a reversible four-electron process with theoretical capacity up to 343 m Ah g-1TPT and energy density up to 718 Wh kg-1TPT in carbonate electrolyte.Besides,it exhibits decent cycling stability and rate performance when hybridized with Ketjen black,displaying a capacity of 181 m Ah g-1TPT at 2.0 A g-1 with a capacity retention of 66%after 6000 cycles,and a capacity of 91 m Ah g-1TPT at 20.0 A g-1.The related parameters are better than those of inorganic and most organic cathode materials reported so far,thus TPT cathode shows good application prospect.Physiochemical characterizations,theoretical calculations and comparative experiments revealed that TPT molecule underwent structural evolution from triplet biradical TPT··2-to quinoid structure TPT4-during the redox processes,and it was confirmed that all triazine and pyridine rings on the TPT molecule were involved in charge storage.（2）Two bipolar organic cathode materials with multiple active centers,1,1’,1"-trimethyl-4,4’,4"-（1,3,5-triazin-2,4,6-triyl）tripyridinium trisiodide（MPT-3I）and1,1’,1"-trimethyl-4,4’,4"-（1,3,5-triazin-2,4,6-triyl）tripyridinium tribromide（MPT-3Br）,were prepared by the methylation of TPT molecules and ion exchange method.Electrochemical tests and mechanism characterization results show that theπ-conjugated MPT3+cation can store four electrons reversibly in the N-type region,and the redox reaction based on I-or Br-anion can store three electrons reversibly in the P-type region.Therefore,the MPT-3I and MPT-3Br cathode can show high discharge specific capacities of 266 m Ah g-1 and 271 m Ah g-1 at 0.10 A g-1,respectively.Due to more electronegative of bromine than iodine,the MPT-3Br cathode exhibits a higher initial voltage platform（3.62 V vs.3.21 V）and energy density(651 Wh kg-1 vs.609 Wh kg-1)than the MPT-3I cathode.