A porous electrode has first (110) and second (112) opposed major surfaces and comprises, based on the total weight on the porous electrode: 60 to 92.5 percent by weight of graphitic carbon fibers (120) having an average fiber diameter of 5 to 10 microns and an average length of 6 to 25 mm; 5 to 25 percent by weight of electrical ly-nonconductive reinforcing fibers (130) having an average fiber diameter of 5 to 25 microns and an average length of 3 to 50 mm, wherein the electrical ly-nonconductive reinforcing fibers are ceramic, glass, glass-ceramic, or a combination thereof; and 2.5 to 15 percent by weight of polymer fibers (140) selected from hydrocarbon polyolefin fibers, perfluorinated polymer fibers, partially fluorinated polymer fibers, chlorinated polyethylene fibers, polyvinyl chloride fibers, polysulfone fibers, polyaryletherketone fibers, and combinations thereof. At least some of the polymer fibers proximal to the first and second major surfaces are melt-bonded to each other. Methods of making the porous electrode, and a membrane-electrode assembly for a redox flow battery including the porous electrode are also disclosed.