Nano-sized oxide filled composite PEO/PMMA/P(VDF-HFP) gel polymer electrolyte for rechargeable lithium and sodium batteries

Developing solid electrolyte for alkali metal batteries is of important significance. A gel polymer electrolyte (GPE) based on the porous composite polymer membrane formed by blending of PEO , PMMA and P(VDF-HFP) is prepared, and the effects of the addition of nano-sized oxide fillers (Al 2 O 3 , TiO 2 , SiO 2 ) on the characteristics of the composite GPEs are investigated. The composite GPE with filling of SiO 2 has more amorphous region and porous structure which can hold more liquid electrolyte without leakage, so the composite GPE can provide high ionic conductivity at room temperature and large Li + or Na + transport number. Furthermore, the composite GPE possesses a large electrochemical window, superior thermal stability and excellent interfacial stability. The composite GPEs can be applied in a variety of lithium and sodium metal batteries and exhibit superior cycling stability and rate performance.