The　search　for　high-performance　organic　redox-active　materials　for　non-aqueous　redox-flow　batteries　remains　a　key　challenge.　Organic　radicals　and　aromatic　imides　are　two　promising　classes　of　redox-active　materials　with　complementary　advantages,　such　as　the　specific　capacity,　operating　voltage,　and　stability,　etc.　Herein,　this　work　reports　two　stable　bifunctional　radicals　synthesized　by　the　C−C　coupling　of　redox-active　phenoxyl　radicals　and　perylene　diimides　(PDIs,　1.)　or　benzo[ghi]perylene　triimides　(BPTIs,　2.).　The　incorporation　of　electron-deficient　PDIs　or　BPTIs　into　phenoxyl　radicals　is　desired,　to　not　only　increase　the　number　of　redox-active　groups　per　molecule　and,　thus,　improve　their　specific　capacities,　but　also　to　increase　the　redox　potential　and　the　stability　of　the　phenoxyl　radicals　and,　thus,　enhances　their　battery　voltages　and　cycle　lives.　When　serving　as　the　redox-active　species　in　the　catholyte　of　a　non-aqueous　static　redox-flow　battery,　both　radicals　1.　and　2.　exhibited　a　cooperatively　enhanced　performance　with　an　unprecedented　initial　discharge　voltage　up　to　3.12　V　versus　Li+/Li,　which　is　the　hitherto　most　presentable　potential　for　imide-　and　radical-based　energy　storage　materials　in　redox-flow　batteries.　©　2018　Wiley-VCH　Verlag　GmbH　&　Co.　KGaA,　Weinheim