Solid-State Ion-Conducting Multiblock Terpolymers

Solid-state multiblock copolymers with two distinct chemistries are well explored and reveal that three-dimensional (3D) continuous network morphologies result in the highest ion conductivities, morphology factors (normalized ion conductivity), and subsequently the highest electrochemical performance. However, these polymers exhibit a limited set of 3D morphologies over a narrow compositional range. Solid-state multiblock terpolymers with three distinct chemistries significantly enhance the accessible phase space and yield more 3D continuous network morphologies over a broader compositional range, yet they are relatively unexplored. In this perspective, solid-state ion-conducting multiblock terpolymers are reviewed, and the results highlight more observed 3D continuous network morphologies and exceptionally higher morphology factors compared to their multiblock copolymer counterparts. To date, only 12 morphologies have been observed in ion-conducting multiblock terpolymers. Future investigations with targeted synthesis can discover many more morphologies, and therefore unlock a new set of materials with ultrahigh ion conductivities and electrochemical performance.