Quasi-solid-state potassium-ion batteries (QSPIBs) are regarded as one of the most promising safety-enhanced energy storage devices. Herein, a facile method for preparing a potassium-ion composite electrolyte membrane on a large scale is presented for the first time. The as-synthesized membrane displays excellent electrochemical stability, good mechanical flexibility, and high ionic conductivity (9.31 × 10^-5 S cm⁻¹ at 25 °C). Furthermore, QSPIBs prepared with this membrane and commercial raw material-based electrodes show superior electrochemical performance even at low temperatures (99.7 mAh g⁻¹ at −20 °C for half QSPIBs and 90.7 mAh g⁻¹ at −15 °C for full QSPIBs), and a promising rate performance (115.6 mAh g⁻¹ for half QSPIBs and 90.9 mAh g⁻¹ for full QSPIBs at 800 mA g⁻¹). The reaction mechanism and structure evolution of a 3,4,9,10-perylene-tetracarboxylicacid-dianhydride (PTCDA) cathode is also systematically studied. The promising characteristics of the prepared low-cost quasi-solid-state potassium-ion batteries in this work open up new possibilities for safer and more durable batteries and a wide range of practical applications in the electronics industry.

准-固态钾离子电池（QSPIBs）被视为最有前途的安全增强的能量存储设备中的一个。在此，首次提出了一种大规模制备钾离子复合电解质膜的简便方法。合成后的膜显示出优异的电化学稳定性，良好的机械柔韧性和高离子电导率（在25°C下为9.31×10 ^-5 S cm ^-1）。此外，用这种膜和市售的基于原料的电极制备的QSPIB即使在低温下也表现出优异的电化学性能（一半的QSPIB在20°C时为99.7 mAh g ^-1和90.7 mAh g ^-1在-15℃下用于全QSPIBs），并有希望的倍率性能（115.6毫安克^-1半QSPIBs和90.9毫安克^-1全QSPIBs以800mA克^-1）。还系统地研究了3,4,9,10-per-四羧酸二酐（PTCDA）阴极的反应机理和结构演变。制备的低成本准固态钾离子电池在这项工作中具有令人鼓舞的特性，为更安全，更耐用的电池以及电子行业的广泛实际应用开辟了新的可能性。