College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering of China, Sichuan University, Chengdu, 610065, China.
School of Aeronautics and Astronautics, Sichuan University, Chengdu, 610065, China.
Small. 2023 Jul;19(27):e2300118. doi: 10.1002/smll.202300118. Epub 2023 Apr 3.
The insufficient ionic conductivity, limited lithium-ion transference number (t +), and high interfacial impedance severely hinder the practical application of quasi-solid polymer electrolytes (QSPEs). Here, a sandwich-structured polyacrylonitrile (PAN) based QSPE is constructedin which MXene-SiO nanosheets act as a functional filler to facilitate the rapid transfer of lithium-ion in the QSPE, and a polymer and plastic crystalline electrolyte (PPCE) interface modification layer is coated on the surface of the PAN-based QSPE of 3 wt.% MXene-SiO (SS-PPCE/PAN-3%) to reduce interfacial impedance. Consequently, the synthesized SS-PPCE/PAN-3% QSPE delivers a promising ionic conductivity of ≈1.7 mS cm at 30 °C, a satisfactory t + of 0.51, and a low interfacial impedance. As expected, the assembled Li symmetric battery with SS-PPCE/PAN-3% QSPE can stably cycle more than 1550 h at 0.2 mA cm . The Li||LiFePO quasi-solid-state lithium metal battery (QSSLMB) of this QSPE exhibits a high capacity retention of 81.5% after 300 cycles at 1.0 C and at RT. Even under the high-loading cathode (LiFePO ≈ 10.0 mg cm ) and RT, the QSSLMB achieves a superior area capacity and good cycling performance. Besides, the assembled high voltage Li||NMC811(loading ≈ 7.1 mg cm ) QSSLMB has potential applications in high-energy fields.
离子电导率不足、锂离子迁移数（t+）有限以及高界面阻抗严重阻碍了准固态聚合物电解质（QSPE）的实际应用。在这里，构建了一种三明治结构的聚丙烯腈（PAN）基 QSPE，其中 MXene-SiO 纳米片作为一种功能性填料，以促进 QSPE 中锂离子的快速转移，并且在基于 PAN 的 QSPE 的表面涂覆了聚合物和塑料结晶电解质（PPCE）界面改性层 3wt.% MXene-SiO（SS-PPCE/PAN-3%）以降低界面阻抗。因此，合成的 SS-PPCE/PAN-3% QSPE 在 30°C 时表现出约 1.7 mS cm 的有希望的离子电导率、0.51 的满意 t+和低界面阻抗。不出所料，具有 SS-PPCE/PAN-3% QSPE 的组装 Li 对称电池可以在 0.2 mA cm 下稳定循环 1550 小时以上。该 QSPE 的 Li||LiFePO 准固态锂金属电池（QSSLMB）在 1.0 C 和 RT 下经过 300 次循环后具有 81.5%的高容量保持率。即使在高负载阴极（LiFePO 约 10.0 mg cm）和 RT 下，QSSLMB 也实现了出色的面积容量和良好的循环性能。此外，组装的高压 Li||NMC811（负载≈7.1 mg cm）QSSLMB 在高能领域具有潜在的应用。
