A novel porous gel polymer electrolyte based on poly(acrylonitrile-polyhedral oligomeric silsesquioxane) with high performances for lithium-ion batteries

- Nanomaterials of POSS are first used in gel electrolyte by chemical polymerization.
- P (AN-POSS) membrane is prepared by phase inversion and has significant porosity.
- The agglomeration of nanoparticles in polymer matrix is solved to a certain extent.
- The crystallinity of PAN is significantly reduced by incorporating POSS.
- The electrochemical performances of PAN electrolyte are significantly enhanced.

A novel porous membrane, based on a polymer matrix of poly(acrylonitrile-polyhedral oligomeric silsesquioxane) (P(AN-POSS)), is prepared by phase inversion process, and the corresponding gel polymer electrolyte (GPE) is further fabricated by immersing the porous membrane into liquid organic electrolyte. The thermal stability and structure of prepared POSS and polymers are investigated. The research indicates that the P(AN-POSS) membrane with copolymerization content of 8 wt% POSS exhibits the better pore structure and superior electrolyte uptake compared with pure PAN membrane, which endows the corresponding GPE with remarkable comprehensive performances: the maximum ionic conductivity value of 6.06 × 10−3 S cm−1 at ambient temperature, the sufficiently stable interface compatibility between GPE and electrode, the excellent lithium ion transference number of 0.59 and the higher electrochemical stability potential of 5.7 V (vs. Li/Li+). At 0.2 C, the GPE with 8 wt% POSS in polymerization based lithium ion battery shows a satisfactory discharge capacity of 148 mAh g−1 and improved capacity retention of 93.7% after 80 cycles.

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