Composite Nanofiber Membrane for Lithium-Ion Batteries Prepared by Electrostatic Spun/Spray Deposition

A new kind of sandwiched composite membrane (SCM) for lithium-ion batteries is prepared by depositing zirconia microparticle between two layers of electrospun poly(vinylidene fluoride-co-hexafluoropropylene) (PVdF-HFP) nanofibers by electrostatic spray deposition. The thermal shrinkage, electrochemical properties of the separator, and cycle performance for batteries with the SCM were investigated. The results show that the SCM has a high electrolyte uptake and easily absorbs electrolyte to form gelled polymer electrolytes (GPEs). The SCM GPEs have a high ionic conductivity of up to 2.06 × 10−3 S cm−1 at room temperature and show a high electrochemical stability potential of 5.4 V. With LiCoCO2 as cathode, the cell with SCM GPEs exhibits a high initial discharge capacity of 149.7 mAh g−1.