Nanowire electrodes for batteries and super-capacitors can produce superior power relative to films of the same materials.  But the Achilles Heel of nanowires is their susceptibility to degradation and failure.  This is particularly true for materials that employ Faradaic reactions requiring ion insertion/deinsertion for energy storage.  Here we describe the preparation of arrays of ultra-long (2.5 mm) Gold@δ-MnO₂, core@shell nanowires.  Gold@δ-MnO₂ nanowires are prepared on glass surfaces using a variant of the Lithographically Patterned Nanowire Electrodeposition process.  All nanowire capacitors prpared from these ultra-long nanowires produce state-of-the-art metrics for energy and power in MnO₂-based systems, but they demonstrate irreversible capacity loss exceeding 20% in ≈4000 - 8000 cycles.  This cycle stability nevertheless represents the state-of-the-art for MnO₂ based electrodes.  Now we have discovered that the addition of poly(methylmethacrylate)(PMMA) to the propylene carbonate (PC) electrolyte extends cycle stability to 100,000 cycles and beyond.  Other energy storage metrics of these systems are not degraded by the PMMA.  In this talk, I describe the results of our experiments, and present data on the charactrerization of these Gold@δ-MnO₂ nanowire systems in PC electrolyte and PC electrolyte containing PMMA, before and after cycling.