Synthesis and evaluation of a new gel polymer electrolyte for high-performance Li-ion batteries from electrospun nanocomposite of PVDF/Ca–Al-layered double hydroxide

Poly(vinylidene fluoride) (PVDF)/Ca–Al-layered double hydroxide(CAL) (PCL) nanocomposite-based nanofabrics were electrospun for application in lithium-ion batteries as gel polymer electrolyte (GPE). The nanofabric exhibited a high β-phase content of 82.79% after the addition of CAL that was synthesized by co-precipitation method. The PCL-based GPE exhibited enhanced electrochemical properties, such as high ionic conductivity, optimal Li-ion transference number, and improved electrolyte uptake due to the presence of a highly interconnected porous structure. The PCL GPE exhibited an ionic conductivity of 3.54 × 10^–3 S cm⁻¹ at ambient temperature, which is much higher than that of pristine PVDF and commercial Celgard^® 2400 separators. Moreover, Li/PCL/LiCoO₂ cell showed an initial discharge capacity of 140.31 mAh g⁻¹, which is superior to that of PVDF and Celgard^® 2400 separators. It also exhibited high coulombic efficiency retention of 99% after 30 cycles of charging. PCL-based GPE showed superior mechanical and low thermal shrinkage properties, indicating its suitability in battery separator application. Graphical abstract: [Figure not available: see fulltext.]