Opening and Constructing Stable Lithium‐ion Channels within Polymer Electrolytes
Yangmingyue Zhao, Libo Li, Da Zhou, Yue Ma, Yonghong Zhang, Hang Yang, Shubo Fan, Hao Tong, Suo Li, Wenhua Qu
Abstract
Abstract Lithium‐ion batteries play an integral role in various aspects of daily life, yet there is a pressing need to enhance their safety and cycling stability. In this study, we have successfully developed a highly secure and flexible solid‐state polymer electrolyte (SPE) through the in situ polymerization of allyl acetoacetate (AAA) monomers. This SPE constructed an efficient Li + transport channel inside and effectively improved the solid‐solid interface contact of solid‐state batteries to reduce interfacial impedance. Furthermore, it exhibited excellent thermal stability, an ionic conductivity of 3.82×10 −4 S cm −1 at room temperature (RT), and a Li + transport number ( t Li+ ) of 0.66. The numerous oxygen vacancies on layered inorganic SiO 2 created an excellent environment for TFSI − immobilization. Free Li + migrated rapidly at the C=O equivalence site with the poly(allyl acetoacetate) (PAAA) matrix. Consequently, when cycled at 0.5C and RT, it displayed an initial discharge specific capacity of 140.6 mAh g −1 with a discharge specific capacity retention rate of 70 % even after 500 cycles. Similarly, when cycled at a higher rate of 5C, it demonstrated an initial discharge specific capacity of 132.3 mAh g −1 while maintaining excellent cycling stability.