Preparation And Characterization Of PEO/LCNF Composite Electrolytes

Due to its significant development in recent years,lithium ion battery（LIB）has participated in many fields of our daily life and production,such as electronic equipment,electric vehicles and energy stowage of power plants.New materials are required in order to improve the battery performance.As the key part of a battery,liquid electrolytes could cause safety problems because of its heat and flammable gas release.Solid state electrolytes（SSE）could keep out of the safety problems and dendrite of Li⁺.Besides,SSE have higher theoretical energy density,which makes it the hotpot of battery researches these years.Polyethylene oxide（PEO）has been considered as the most promising solid polymer electrolyte base.Although it has poor ionic conductivity,plenty of O atoms with lone pair electrons make it easy to coordinate with Li and other atoms,resulting to the possibility of improving ionic conductivity through the adding of lithium salts and inorganic particles.Further,lignocellulsic nanofibrils（LCNF）with–OH groups of carbohydrate structures are supposed to be of good compatibility with PEO,which is in advantage of preparing composite electrolytes.At the same time,the versatile,low-cost and sustainable wood based LCNF could also do favor to green economy.In this work,based on the study of PEO/LCNF composite electrolytes,composite electrolytes with hydroxyls,pyrrolidone,quinoline are designed and prepared.Tested with infrared radiation spectrum,differential scanning calorimeter（DSC）and electrochemical methods,several low-cost and good performance all solid and quosi solid LIBs are obtained,among which PEO-LCNF（PEO,plasticizer,LCNF and LiClO₄,w/w/w/w=10:5:1.5:1.5）and PEO-pyrrolidone derivatives（dopant,PEO and LiTFSI,w/w/w=5:75:20）battery systems show better performance in conductivity and cyclic stability than PEO system,showing promising application potential.