Li₇La₃Zr₂O₁₂ (LLZO) with cubic phase structure is a kind of lithium-ion-conducting nanoparticles. According to the previous studies, incorporation of c-LLZO can improve electrochemical properties of PEO-based composite polymer electrolytes (CPEs). Therefore, in our study, we synthesized a kind of room-temperature-stable cubic phase LLZAO (Li_6.25La₃Zr₂Al_0.25O₁₂) nanofibers, and we aimed to confirm the optimal content of LLZAO nanofibers in PEO-based CPEs. With the incorporating 10 wt% LLZAO nanofibers, ionic conductivity of CPEs are 9.87×10⁻⁵ S cm⁻¹ at 30 °C and 8.66×10⁻⁴ S cm⁻¹ at 60 °C. The Li/CPE incorporating 10 wt% LLZAO nanofibers/Li symmetric cell exhibits little voltage fluctuation in 1000 cycles under a current density of 0.5 mA cm⁻², demonstrating better cycling stability with long cycle life. The LiFePO₄/CPE incorporating 10 wt% LLZAO nanofibers/Li cell has a high initial discharge-specific capacity of 155.6 mAh g⁻¹ under 0.1 C rate at 60 °C and remains 94.5% of capacity after 100 cycles. This cell also has great cycling performance under 0.2 C and 0.5 C rate, indicating good rate performance. Our work indicates that incorporation of LLZAO nanofibers enhances electrochemical properties and cycling stability of PEO-based all-solid-state lithium-ion batteries.

中文翻译：

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掺有Li 6.25 La 3 Zr 2 Al 0.25 O 12纳米纤维的复合聚合物电解质增强全固态锂离子电池的循环稳定性

具有立方相结构的Li ₇ La ₃ Zr ₂ O ₁₂（LLZO）是一种传导锂离子的纳米粒子。根据先前的研究，掺入c-LLZO可以改善PEO基复合聚合物电解质（CPE）的电化学性能。因此，在本研究中，我们合成了一种室温稳定的立方相LLZAO（Li _6.25 La ₃ Zr ₂ Al _0.25 O ₁₂）纳米纤维，旨在确定PEO基CPE中LLZAO纳米纤维的最佳含量。通过掺入10重量％的LLZAO纳米纤维，CPE的离子电导率为9.87×10 ^-5  S cm ^-1在30°C和8.66×10 ^-4  S cm ^-1在60°C下。结合有10wt％的LLZAO纳米纤维/ Li对称电池的Li / CPE在0.5mA cm ^-2的电流密度下在1000次循环中显示出很小的电压波动，证明了更好的循环稳定性和长循环寿命。掺有10 wt％LLZAO纳米纤维/ Li电池的LiFePO ₄ / CPE具有155.6 mAh g ^-1的高初始放电比容量在60°C下以0.1 C的速率加热，在100次循环后仍保持94.5％的容量。该电池在0.2 C和0.5 C的速率下也具有出色的循环性能，表明速率性能良好。我们的工作表明，掺入LLZAO纳米纤维可增强PEO基全固态锂离子电池的电化学性能和循环稳定性。