Cell frame, electrochemical cell, cell stack and operating method

Described and illustrated is a cell frame for forming an electrochemical cell, in particular of a redox flow battery, peripherally enclosing at least one cell interior and including at least one feed channel for feeding electrolyte into the cell interior, wherein the feed channel has an inlet opening, spaced from the cell interior, for the electrolyte to be fed and an outlet opening, adjacent to the cell interior, for the electrolyte to be fed to flow out into the cell interior. In order that the power density can be increased, it is provided that the feed channel has at least one transport channel, connecting at least in sections the inlet opening with the outlet opening, for transporting the electrolyte through the feed channel into the cell interior and at least one return channel for partially returning the electrolyte to be fed counter to the transport direction (T) of the electrolyte to be fed in the transport channel, in that the return channel is in fluid contact with the transport channel via in each case at least one entry opening for entry of the electrolyte to be returned and exit opening for exit of the electrolyte to be returned, spaced from one another in the transport direction (T) of the electrolyte to be fed.