Gel polymer electrolyte based on p(acrylonitrile-maleic anhydride) for lithium ion battery

Highlights: • P(AN-MAH) is used as gel polymer electrolyte for the first time. • P(AN-MAH) based membrane is prepared by phase inversion. • The poor compatibility of PAN based GPE is significantly improved. • The lithium ion transference number of PAN based GPE is obviously increased. • Polymerization of MAH enhances the thermal stability to PAN matrix. A polymer matrix of poly(acrylonitrile-maleic anhydride) (P(AN-MAH)) is used to prepare a novel porous membranes by phase inversion. The membranes are immersed into liquid electrolyte to form gel polymer electrolyte (GPE) used in lithium ion batteries (LIBs). The results indicate that P(AN-MAH) is successfully synthesized and the membrane of P(AN-MAH) copolymer with adding mass ratios of AN: MAH = 4:1 exhibits superior pore structure and better thermal stability compared with that of pure PAN membrane, which endows the corresponding GPE with excellent comprehensive performances: the considerable ionic conductivity (3.03 × 10⁻³ S cm⁻¹ at room temperature), fine compatibility between GPE and electrode, eminent lithium transference number (t_Li⁺ = 0.57), and high enough electrochemical stability potential (up to 5.4 V (vs. Li/Li⁺)). Accordingly, in constant current charging/discharging cycle, the prepared battery for the GPE also presents excellent initial discharge capacity, C-rate and cycling performances.