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Potassium-ion batteries (PIBs) are attractive for energy storage due to their obvious cost advantage compared with lithium-ion batteries. However, their commercialization is plagued by the lack of high-performance electrode materials. In this work, a novel polyanionic anode material K2.13V1.52Ti0.48(PO4)3 (KVTP) is prepared for the first time, which exhibits excellent electrochemical properties when used as the electrode material of a PIB. After coating with carbon, the obtained KVTP@C composite delivers a high specific capacity of 136 mA·h/g at a current density of 10 mA/g (0.073C) and achieves a long life span of 225 cycles (ca. 7.5 months) with a specific capacity of 106.7 mA·h/g, corresponding to 78.55 % of the maximum value. Moreover, the framework host can provide a capacity of 92.6 mA·h/g at a rate of 100 mA/g (0.73 C) and retains 69.3 % of the initial capacity at the 1000th cycle. The outstanding cycling stability is attributed to the robust lattice structure revealed by ex situ X-ray diffraction.