NOVELTY - Several microcell sheets (60,62,64,66) have respective microcell fibers arranged in parallel and planar configuration. The inner current collectors of the fibers axially extend from one edge of the sheet, and the external current collectors contacting the upper microcell fiber layer extend from the opposite edge. The adjacent microcell sheets are separated by respective insulating sheets (94,96,98).    USE - Microcell assembly for electrochemical device (claimed) such as fuel cell (claimed) and battery cell.    ADVANTAGE - Simplifies bundling of fibers in modular assemblies for battery cell applications. Provides compact unitary, overall construction which provides high density energy output and enables minimization of volume of the fuel cell or other electrochemical cell. The parallel connection provides very high current density per unit volume, allowing the assembly to operate at high voltage and high efficiency.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for the following:    (i) Microcell sub-bundle article;    (ii) Series connected assembly of microcell sub-bundles;    (iii) Microcell article;    (iv) Microcell assembly fabrication method;    (v) Microcell module fabrication method;    (vi) Microcell sub-bundle article fabrication method;    (vii) Microcell article fabrication method;    (viii) Fibrous microcell structure fabrication method;    (ix) Process system;    (x) Fiber microcell article manufacturing process;    (xi) Electrochemical cell module;    (xii) Microcell module;    (xiii) Electrochemical energy generation process;    (xiv) Thermal management method of electrochemical cell module;    (xv) Thermal management method of microcell module;    (xvi) Electrochemical device;    (xvii) Fuel cell;    (xviii) Microcell structure;    (xix) Electrochemical cell device manufacturing method;    (xx) Fibrous microcell structure;    (xxi) Water management method in electrochemical device;    (xxii) Coated fiber;    (xxiii) Corrosion-resistant fiber fabrication method.    DESCRIPTION OF DRAWING(S) - The figure shows an exploded perspective view of microcell assembly.    Microcell sheets (60,62,64,66)    Insulating sheets (94,96,98)