Mechanically compliant and lithium dendrite growth-suppressing composite polymer electrolytes for flexible lithium-ion batteries

We demonstrate mechanically compliant and lithium dendrite growth-suppressing composite polymer electrolytes for use in flexible lithium-ion batteries. This new composite polymer electrolyte (referred to as "CPE") is fabricated via an exquisite combination of UV (ultraviolet)-cured ethoxylated trimethylolpropane triacrylate macromer (serving as a mechanical framework) and Al₂O₃ nanoparticles (as a functional filler) in the presence of a high boiling point liquid electrolyte. A distinctive structural feature of the CPE is the close-packed Al ₂O₃ nanoparticles in the liquid electrolyte-swollen ETPTA macromer matrix. Owing to this unique morphology, the CPE provides significant improvements in the mechanical bendability and suppression of lithium dendrite growth during charge-discharge cycling.