An electrode structure includes: a base layer including a first active material; a plurality of active material plates, a plate of the plurality of active material plates including opposing side walls and a lower wall, wherein the lower wall is disposed on the base layer, wherein adjacent plates of the plurality of active material plates are spaced apart from each other, and wherein an active material plate of the plurality of active material plates includes a second active material; and a channel between adjacent plates of the plurality of active material plates, wherein the channel includes a first channel region defined by adjacent side walls of the adjacent plates, and a second channel region connected to the first channel region and defined by a lower wall of the adjacent plates and the base layer.