A flexible solid polymer electrolyte enabled with lithiated zeolite for high performance lithium battery

Solid-state lithium batteries using composite polymer electrolytes(CPEs)have attracted much attention owing to their higher safety compared to liquid electrolytes and flexibility compared to ceramic electrolytes.However,their unsatisfactory lithium-ion conductivity still limits their development.Herein,a high ion conductive CPE with multiple continuous lithium pathways is designed.This new electrolyte consists of poly(vinylidene fluorideco-hexafluoropropylene)(PVDF-HFP)and lithiated X type zeolite(Li-X),which possesses a high ionic conductivity(1.98×10^(-4)S/cm),high lithium transference number(t_(Li^(+))=0.55),wide electrochemical window(4.7 V),and excellent stability against the lithium anode.Density functional theory(DFT)calculation confirms that the Lewis acid sites in zeolite can graft with N,N-dimethylformamide(DMF)and PVDF-HFP chains,resulting in decreased crystallinity of polymer and providing rapid Li+transmission channels.When used in a full cell,the solid Li|Li-X-3%|LiFePO_(4) cell displays excellent cycling stability and rate performance at room temperature and 60℃.Furthermore,pouch cells with the Li-X-3%electrolyte exhibit brilliant safety under extreme conditions,such as folding and cutting.Thus,this proposed zeolite-PVDF-HFP CPE represents a promising potential in the application of making a safer,higher performing,and flexible solid-state lithium battery.