Abstract: A microfibrous fuel cell structure of elongated form with a longitudinal axis. Such microfibrous fuel cell includes electrocatalyst layers supported by a fiber network formed of unidirectional or substantially unidirectional conductive fibers. The conductive fibers of such fiber network are oriented parallelly or substantially parallelly to the longitudinal axis of the fuel cell, therefore allowing such fiber network to conform to the curvature of the microfibrous fuel cell along the radial direction but without causing overbending of the individual fibers.

Abstract: The present invention relates to a substrate-supported process for continuous and automated manufacturing of microfibrous fuel cells and other electrochemical cells. Specifically, a removable substrate layer is formed around an inner current collector, followed by sequentially coating multiple structure layers, such as the inner catalyst layer, the membrane separator, and the outer catalyst layer, over such removable substrate layer, and subsequent removing such removable substrate layer, so as to form a lumen around the inner current collector, to allow passage of fluid therethrough. The removable substrate layer preferably comprises a water-soluble polymer, such as polyvinyl pyrrolidone (PVP), polyvinyl alcohol (PVA), or polyethylene glycol (PEG).

Abstract: The present invention relates to a substrate-supported process for continuous and automated manufacturing of microfibrous fuel cells and other electrochemical cells. Specifically, a removable substrate layer is formed around an inner current collector, followed by sequentially coating multiple structure layers, such as the inner catalyst layer, the membrane separator, and the outer catalyst layer, over such removable substrate layer, and subsequent removing such removable substrate layer, so as to form a lumen around the inner current collector, to allow passage of fluid therethrough. The removable substrate layer preferably comprises a water-soluble polymer, such as polyvinyl pyrrolidone (PVP), polyvinyl alcohol (PVA), or polyethylene glycol (PEG).

Abstract: The present invention relates to processes for fabricating polymeric hollow fibers. Specifically, a removable solid core fiber is provided for coating one or more layers of a polymeric membrane-forming material thereon. After treating the polymeric membrane-forming material layer to form a solidified polymeric membrane having a permanent tubular shape, the solid core fiber is selectively removed, leaving an elongated lumen inside the solidified polymeric membrane, which forms a high quality polymeric hollow fiber that is substantially free of deformation defects. The solid core fiber can be made of a removable substrate material, such as water-soluble polymers polyvinyl pyrrolidone (PVP), polyvinyl alcohol (PVA), or polyethylene glycol (PEG), which are subsequently and selectively removable by water. Alternatively, the solid core fiber can be coated with a removable substrate material, which imparts removability to such solid core fiber.

Abstract: The present invention relates to a substrate-supported process for continuous and automated manufacturing of microfibrous fuel cells and other electrochemical cells. Specifically, a removable substrate layer is formed around an inner current collector, followed by sequentially coating multiple structure layers, such as the inner catalyst layer, the membrane separator, and the outer catalyst layer, over such removable substrate layer, and subsequent removing such removable substrate layer, so as to form a lumen around the inner current collector, to allow passage of fluid therethrough. The removable substrate layer preferably comprises a water-soluble polymer, such as polyvinyl pyrrolidone (PVP), polyvinyl alcohol (PVA), or polyethylene glycol (PEG).