Synthesis and Characterization of a Cyclic Polyacetonitril Oligomer and its Application on Solid Polymer Electrolyte

Here we introduce a new synthetic approach to grow polyacetonitrile (PAcN) oligomer via electrochemical method, and the polymerization degree of PAcN oligomer is investigated completely by mass spectrum. The PAcN oligomer with well-defined polymerization degree is obtained in this work, which shows an excellent heat resistance till 400 °C. Particularly, the PAcN oligomer is successfully applied as an additive of the solid polymer electrolyte for lithium batteries. By adding 3 wt. % PAcN oligomer, the ionic conductivity of the PEO-based SPE grows by two orders of magnitude and reaches 2.59×10−5 S/cm at 30 °C. Furthermore, the electrochemical stability window and mechanical processing property of SPE are also enhanced greatly by adding of PAcN oligomer. The PAcN oligomer is proved to be a promising additive for SPE.