The prominent objective of this study is to improve the thermal shrinkage and wettability of lithium-ion battery membrane separators based on Polyacrylonitrile (PAN) formed using an electrospinning technique. To achieve this goal, a PAN blended with highly hydrophilic Polyvinylalcohol (PVA) is formed, using malonic acid (MA) as a cross-linker. Due to the excellent hydrophilic properties of PVA and the network formation inside the separators (because of the MA crosslinker presence), the results show significant improvement in the separator properties. For this reason, at the optimum concentrations of 5 wt.% PVA and 5 wt.% MA (sample F4), an increase of wettability (contact angle from 85 for pure PAN to 42 for the F4 separator) is able to be seen. The electrolyte uptake was significantly increased, as for the F4 sample is increased to 1,150%, which is 2.67 times higher than the PAN with 430%. The improved separators showed higher porosity, better tensile strength, lower thermal shrinkage, and better electrochemical performance than the pure PAN separator. It showed an ion conductivity of 3.03 mS/cm, a wide electrochemical stability window of 5.2 V and an initial discharge capacity of 156.4 mAh/g.

The present study aimed to investigate the mechanical, thermal, and electrochemical properties of Polyacrylonitrile (PAN) electrospun separators in the presence of Polyvinylalcohol (PVA) hydrophilic materials and Malonic Acid (MA) crosslinker inside the lithium-ion batteries. The results showed that the M3 modified separator with the MA to PVA+MA (wt./wt.) optimum ratio of 37.5 % had the best performance in all tests. This separator had a value of 3.16 mS/cm in the ion conductivity test. Additionally, it had an electrolyte uptake of 1172 % (2.39 times more than the neat PAN separator) and thermal shrinkage of 7.4 % at 180 °C, where this value was 14.5 % for neat PAN separator at the same experimental condition. Furthermore, the acceptable performance in the battery performance tests was compared with other separators.