PEO复合PVDF-HFP基聚合物电解质的离子传导及电化学性能调制研究OA北大核心

Polyvinylidene fluoride-co-hexafluoropropylene(PVDF-HFP)-based polymer elec-trolytes suffer from issues such as low ionic conductivity and poor interfacial stability with lithium(Li)metal at room temperature,which limit their range of applications.To address this,poly(ethylene oxide)(PEO),which possesses elasticity and viscosity,is incorporated into the PVDF-HFP-based electrolyte to enhance its ionic conductivity and interfacial compatibility with electrodes.The electrolyte,mixed with PVDF-HFP and PEO in a 3∶1 mass ratio,exhibits the highest ionic conductivity(5.618×10-4 S·cm-1)and lithium ion(Li+)transport number(0.403)at room tem-perature.The Li-Li symmetric cells assembled with this electrolyte can stably undergo electroplating-stripping for up to 650 h under a current density of 0.10 mA·cm-2 at 25℃.Full batteries,as-sembled with a LiCoO2 cathode and lithium anode,maintain a specific capacity of 115.9 mA·h·g-1 after 50 cycles at 0.2 C-rate.