Flexible poly(ethylene carbonate)/garnet composite solid electrolyte reinforced by poly(vinylidene fluoride-hexafluoropropylene) for lithium metal batteries
Flexible poly(ethylene carbonate)/garnet composite solid electrolyte reinforced by poly(vinylidene fluoride-hexafluoropropylene) for lithium metal batteries
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锂金属电池用聚偏氟乙烯-六氟丙烯增强柔性聚碳酸乙烯酯/石榴石复合固体电解质
DOI：
10.1016/j.jpowsour.2018.05.006
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发表时间：
2018-07-15
影响因子：
9.2
通讯作者：
Fan, Li-Zhen
中科院分区：
文献类型：
--
作者：
He, Zijian;Chen, Long;Fan, Li-Zhen
高性能固态可充电锂电池需要具有高离子电导率、大柔性和易加工性的固态电解质。本文采用溶液燃烧法合成了纳米立方相Li 6. 2sAl 0. 25 La 3 Zr 2 O 12（LLZO），并将其与聚碳酸乙烯酯（PEC）、聚偏氟乙烯-六氟丙烯（P（VdF-HFP））和双氟磺酰亚胺锂（LiFSI）组成柔性石榴石基复合固体电解质。在柔性复合固体电解质中，LLZO纳米粒子作为陶瓷基体，对离子电导率和锂离子迁移数（t（Li+））有积极的影响。PEC作为一种快离子导电聚合物，具有高的t（Li+）。P（VdF-HFP）作为粘结剂，可提高力学性能。因此，所制备的复合固体电解质表现出高t（Li+）（0.82）和极好的热稳定性（燃烧后保留LLZO基质）。用该柔性复合固体电解质组装的全固态LiFePO 4竖条锂电池提供了121.4 mAh g（-1）的高初始放电比容量和55 ℃下良好的循环稳定性。
Solid-state electrolytes with high ionic conductivities, great flexibility, and easy processability are needed for high-performance solid-state rechargeable lithium batteries. In this work, we synthesize nanosized cubic Li6.2sAl0.25La3Zr2O12 (LLZO) by solution combustion method and develop a flexible garnet-based composite solid electrolyte composed of LLZO, poly(ethylene carbonate) (PEC), poly(vinylidene fluoride-hexafluoropropylene) (P(VdF-HFP) and lithium bis(fluorosulfonyl)imide (LiFSI)). In the flexible composite solid electrolytes, LLZO nanoparticles, as ceramic matrix, have a positive effect on ionic conductivities and lithium ion transference number (t(Li+)). PEC, as a fast ion-conducting polymer, possesses high t(LI+) inherently. P(VdF-HFP), as a binder, can strengthen mechanical properties. Consequently, the as-prepared composite solid electrolyte demonstrates high t(Li+) (0.82) and superb thermal stability (remaining LLZO matrix after burning). All-solid-state LiFePO4 vertical bar Li cells assembled with the flexible composite solid electrolyte deliver a high initial discharge specific capacity of 121.4 mAh g(-1) and good cycling stability at 55 degrees C.