An electrochemical-type power supply source (1), comprising:
- an electrochemical stack (2), configured to generate electric power, in the presence, internally, of electrolytic fluid, having a number (n) of distinct groups of galvanic cells (4) and a corresponding number of electrolyte inlet pipes (8) for the introduction of electrolyte into the respective groups of galvanic cells (4) and electrolyte outlet pipes (9) for the extraction of electrolyte from the respective groups of galvanic cells (4);
- a main tank (5), fluidically coupled to said electrochemical stack (2) and designed to contain electrolytic fluid;
- and
- a recirculation system (6, 10), configured to establish a circulation path for circulation of the electrolytic fluid between said main tank (5) and said electrochemical stack (2), characterized by comprising a valve system (20), coupled to said electrolyte inlet pipes (8) and/or electrolyte outlet pipes (9) and operatively controllable to jointly modify hydraulic and electrical characteristics of the electrolytic-fluid circulation path, in response to a change of a power delivery condition by said power supply source (1);
- wherein said valve system (20) comprises:
- an inlet valve arrangement (24), for each electrolyte inlet pipe (8), coupled to the input of the respective electrolyte inlet pipe (8);
- and
- an outlet valve arrangement (25), for each electrolyte outlet pipe (9), coupled to the output of the respective electrolyte outlet pipe (9);
- wherein each inlet valve arrangement (24) and each outlet valve arrangement (25) defines a respective inlet (IN) and a respective outlet (OUT) for the electrolytic fluid and comprises:
- a direct fluidic path (26), which fluidically connects the respective inlet (IN) and the respective outlet (OUT) through a first path with a first length/section ratio;
- a secondary fluidic path (27), which fluidically connects the respective inlet (IN) and the respective outlet (OUT) by means of a second path with a second length/section ratio, wherein the second length/section ratio is greater than the first length/section ratio;
- a valve device (28), operable in a first position in which it closes, alternatively in a second position in which it opens, said direct fluidic path (26) between said inlet (IN) and said outlet (OUT),
- wherein said secondary fluidic path (27) is traversed by said electrolytic fluid, in the closing position of said direct fluidic path (26) by said valve device (28).