Research

    The fast development of portable electronic devices and electric vehicles (EV) or hybrid electric vehicles (HEV) have raised a strong demand for high performance energy storage system and provoked extensive studies on exploring and developing high-performance lithium ion batteries (LIBs).

    Gel polymer electrolyte (GPE) is indicated as an excellent choice as the next generation electrochemical power source since its high energy density, good cyclability, flexible characteristics and safety.

    In our study, we used the poly(ethylene oxide) (PEO)-based and poly(acrylonitrile) (PAN)-based copolymer to synthesize GPEs for lithium-ion batteries.

Result

    Our GPEs showed good ionic conductivity and higher electrochemical window than liquid electrolyte. The GPEs leads to an increase in mobility of both ions and polymer segments that assists ion transport. The stability windows of the GPE cells were exceptionally wide, which is very beneficial for the application of these GPEs in LIBs using high-voltage cathode materials such as LiCoMnO4, Li2NiMn3O8, and LiNi1/3Mn1/3Co1/3O2. The GPEs were superior to the LE in preserving the energy at high power values. Because of the superior ability in preserving energy at high rates, GPEs must have robust interfaces with the electrodes and is expected to have a long cycle life.

Prospect

    GPE cell is the most successful storage device which has been widely used in the lithium ion batteries due to its virtues such as easy preparation, high electrochemical window and high power capacity, but the cycling performance of the current GPE based lithium ion battery is still not satisfying. To meet the high power capacity and long cycle life requirements of lithium ion batteries for electrical vehicles and new electronic devices, our research are interested in the development of the GPE cell with long cycling performance.