Described herein are systems and methods for the management and control of electrolyte within confined electrochemical cells or groups (e.g. stacks) of connected electrochemical cells, for example, in an electrolyzer. Various embodiments of systems and methods provide for the elimination of parasitic conductive paths between cells, and/or precise passive control of fluid pressures within cells. In some embodiments, a fixed volume of electrolyte is substantially retained within each cell while efficiently collecting and removing produced gases or other products from the cell.