NOVELTY - A three-dimensional electrode array comprises several plate electrodes (801), where each plate electrode includes an array of apertures (802) arranged in parallel orientation such that each aperture of an individual plate electrode is aligned along an alignment axis passing through an aperture of each of all other plate electrodes, and several rod electrodes which are not in physical contact with plate electrodes and arranged such that each rod electrode extends a length along an alignment axis passing through an aperture of each plate electrode.    USE - Three-dimensional electrode array is used for primary electrochemical cell, secondary electrochemical cell, fuel cell, capacitor, supercapacitor, flow battery, metal-air battery and semi-solid battery (all claimed).    ADVANTAGE - The electrochemical storage device using the three-dimensional electrode array has high discharge reliability, reduced self-discharge rate, and is economical and lightweight.    DETAILED DESCRIPTION - A three-dimensional electrode array comprises several plate electrodes, where each plate electrode includes an array of apertures arranged in parallel orientation such that each aperture of an individual plate electrode is aligned along an alignment axis passing through an aperture of each of all other plate electrodes, and several rod electrodes which are not in physical contact with plate electrodes and arranged such that each rod electrode extends a length along an alignment axis passing through an aperture of each plate electrode. The surface area (a) includes a cumulative surface area of several plate electrodes. The surface area (b) includes a cumulative surface area of each aperture array. The surface area (c) includes a cumulative surface area of each of the several rod electrodes. INDEPENDENT CLAIMS are included for the following:    (1) method of controlling temperature of electrochemical cell;    (2) redox flow energy storage device;    (3) method of operating redox flow energy storage device; and    (4) redox flow battery.    DESCRIPTION OF DRAWING(S) - The drawing shows the schematic structure of three-dimensional electrode array.    Plate electrode (801)    Aperture (802)    Sides (804B,804C)