Abstract: The present invention relates to microfibrous fuel cell sub-bundle structures, fuel cell bundles and fuel cell assemblies formed by such fuel cell sub-bundles and bundles. Specifically, a fuel cell sub-bundle is provided, which comprises multiple microfibrous fuel cells. Each microfibrous fuel cell comprises: (a) a hollow microfibrous membrane separator comprising an electrolyte medium, (b) an inner electrocatalyst layer in contact with an inner surface of such membrane separator, (c) an outer electrocatalyst layer in contact with an outer surface of such membrane separator, and (d) an individual current collector in electrical contact with the inner surface of such membrane separator. Each of such multiple microfibrous fuel cells is in electrical contact with a common current collector at the outer surface of its membrane separator.

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 provides microfibrous direct methanol fuel cells that comprise microfibrous hollow membrane separators with fiber-reinforces ion exchange polymeric membrane walls. Specifically, the fiber-reinforces ion exchange polymeric membrane wall of each microfibrous direct methanol fuel cell comprises one or more continuous fibers, which extend along directions that are substantially parallel to a longitudinal axis of the microfibrous fuel cell. The present invention also provides microfibrous direct methanol fuel cells that each comprise a first and second microfibrous hollow membranes, wherein the first microfibrous hollow membrane comprises an ion-exchange polymer and defines a bore side and a shell side for separating an anode from a cathode, and the second microfibrous hollow membrane is disposed at either the bore side or the shell side of the first microfibrous hollow membrane for providing controlled delivery of a methanol-containing fuel fluid.

Abstract: The present invention relates to a microfibrous fuel cell structure of elongated form with a longitudinal axis. Such microfibrous fuel cell comprises 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.