High-Performance Gel Polymer Electrolyte with Self-Healing Capability for Lithium-Ion Batteries

Polymer electrolytes (PEs) are predicted to be an alternative to liquid electrolytes for lithium-ion batteries (LIBs) since they can overcome the problems of leakage and electrolyte flammability issues. However, polymer electrolytes often suffer from disappointing cracks or breakage, which will lead to short circuits and bring some safety issues. Furthermore, the undesirable ionic conductivity at room temperature also limits their practical application. Here, a novel gel polymer electrolyte (GPE) was proposed. The cross-linking network was formed by adding supramolecular copolymer PEG-UPy to the cross-linking matrix of poly(ethylene oxide) (PEO) and polyvinylidene fluoride hexafluoropropylene (PVDF-HFP), and the resulting GPE has the advantages of good flexibility, high mechanical strength, high ionic conductivity (7.5 × 10–4 S cm–1, RT) and can be self-repaired without external stimulation. In addition, the GPE exhibits good interfacial stability with the electrode, which can be used in high-performance lithium-ion batteries with stable reversible electrochemical reactions and excellent cycling stability.