A fluid cooled electrical capacitor assembly (10) includes a stack of honeycomb sheet-like structures (12) of dielectric material with an electrode (16) between each pair of honeycomb sheet-like structures. Alternate electrodes are electrically coupled together to each other and may be coupled to respective terminals of an electrical circuit. Fluid passages (20) in the honeycomb sheet-like structures provide a place for fluid (20a) to affect electrical characteristics of the capacitor assembly and/or to provide for cooling while preventing the fluid from contacting the electrodes. A method of assembling a capacitor assembly includes placing capacitor subunits including a dielectric honeycomb sheet-like structure and an electrode in parallel planar, overlying relation with the honeycomb. A method of cooling a capacitor assembly of dielectric honeycomb structure and electrodes includes directing a fluid through flow channels in the honeycomb structure.