The invention illustrates and describes a cell (1) of a redox flow battery, having at least one cell frame element (2, 3, 4), a diaphragm (15) and two electrodes (5), wherein the at least one cell frame element (2, 3, 4), the diaphragm (15) and the two electrodes (5) surround two cell interior spaces (10) which are separate from one another, wherein at least four separate channels (6, 7, 8, 9) are provided in the at least one cell frame element (2, 3, 4) such that different electrolyte solutions can flow through the two cell interior spaces (10), and wherein the cell (1), with the exception of the at least four separate channels (6, 7, 8, 9), is of liquid-tight design. In order to be able to provide redox flow batteries with a relatively high power density, it is proposed that at least the at least one cell frame element (2, 3, 4) is welded to the diaphragm (15), the two electrodes (5) and/or to at least one further cell frame element (2, 3, 4).