Electrospinning Equipment: High-Performance PVdF - HFP/rGO Electrolytes for Li-ion Batteries

As global energy consumption continues to rise, the need to transition to renewable energy sources is becoming increasingly urgent. Although renewable energy is abundant, it is intermittent, making efficient energy storage crucial. Lithium - ion batteries (LIBs) have attracted significant attention in the energy storage field due to their high energy density, long cycle life, and reliable charge - discharge efficiency. Gel polymer electrolytes (GPEs), which combine the high ionic conductivity of liquid electrolytes with the safety of solid electrolytes, have great potential applications in fields such as fuel cells, sensors, lithium batteries, and supercapacitors. Among them, PVdF - HFP, with its unique C - F bonds, has good thermal stability, electrochemical stability, and a high dielectric constant, making it an ideal material for preparing GPEs. However, its crystalline phase can hinder ion migration.  

To address this challenge, a research team from B.S. Abdur Rahman Crescent Institute of Science and Technology in India published their latest research findings titled "Research on High - Performance Electrolytes for Lithium - Ion Batteries Based on Electrospinning Technology" in the journal Journal of Electronic Materials. The team used an electrospinning machine to successfully prepare composite fiber membranes of poly(vinylidene fluoride - co - hexafluoropropylene) (PVdF - HFP) and reduced graphene oxide (rGO) through electrospinning technology and applied them to lithium - ion battery electrolytes. The research shows that this composite fiber membrane has excellent ionic conductivity, electrochemical stability, and cycling performance, providing an innovative material solution for the development of high - performance energy storage devices.

In the research, different concentrations of rGO were added to the PVdF - HFP solution, and fiber membranes were successfully prepared by the electrospinning device through the electrospinning process at specific voltages and distances. These fiber membranes have a uniform fiber structure and good morphology, providing a basis for subsequent electrochemical performance tests. Scanning electron microscopy (SEM) images show that rGO is distributed on the surface of PVdF - HFP fibers in the form of beads. This structure increases the roughness of the fiber membrane and provides good porosity, which is helpful for electrolyte absorption and ion transport.

The experimental results show that with the increase in rGO content, the porosity and electrolyte absorption capacity of the PVdF - HFP/rGO fiber membranes increase significantly. The high specific surface area and porous structure of rGO enable it to absorb more electrolytes, thus enhancing the performance of the electrolyte. (Figure 7)

By incorporating rGO, the ionic conductivity of the PVdF - HFP/rGO fiber membranes is significantly improved, reaching an order of magnitude of 10⁻⁴ S cm⁻¹. In addition, the lithium - ion transference number (tLi+) is close to 1, indicating a high migration efficiency of lithium ions in the electrolyte, which is very important for improving the charge - discharge efficiency of the battery. (Figures 8, 11)

The results of linear sweep voltammetry (LSV) tests show that the battery based on the PVdF - HFP/rGO fiber membrane has an electrochemical stability window of up to 5.6 V, indicating that the electrolyte has good oxidation stability in high - voltage applications and can withstand higher operating voltages, thereby enhancing the overall performance of the battery.

The cycling performance test results show that the battery based on the PVdF - HFP/rGO fiber membrane exhibits excellent stability and high discharge capacity during the cycling process. The discharge capacity increases with the increase in rGO content, reaching a maximum of 161 mA h g⁻¹. This good cycling stability is attributed to the high ionic conductivity of the electrolyte and its structural stability during the cycling process, further demonstrating the high performance of the electrolyte. (Figure 13)

In conclusion, due to higher ionic conductivity and good performance of the electrolyte during the cycling process, these electrolytes have better cycling stability. Therefore, PVdF - HFP/rGO fibrous electrolytes are very suitable and promising candidates for lithium - ion batteries. This research provides a new direction for the development of high - performance energy storage devices.

Article source: https://doi.org/10.1007/s11664-025-11745-6