Abstract: Enhanced storage efficiency, reliability and durability of a redox flow battery system are achieved by employing distinct pluralities or groups of cells wherein all the cells of a first plurality have porous metallic electrodes in both compartments through which respective electrolyte solutions flow during a charging process of the battery system, and all cells of a second plurality may have porous carbon felt electrodes in both flow compartments through which the respective electrolyte solutions flow during a discharging process of the battery systems or solely in the compartment through which the negatively charged electrolyte solution flows and a porous metallic electrode in the other compartment where the positively charged electrolyte solution flows. All the cells of both groups of cells may be defined by repetitive sequences of stackable elements, according to a common bipolar or monopolar cell stack architecture.

Abstract: A frameless bipolar cell stack architecture with either internal manifolds of circulation of electrolyte solutions “in parallel” through all respective cell compartments or internal ducting adapted to provide for “serial” flow paths of the electrolyte solutions in succession through all respective cell compartments of the stack, does not employ any plastic frame and employs substantially planar bipolar electrical interconnects (I) of substantially homogeneous electrical conductivity with a perimeter that super-imposes to the perimeter of any other element of the stack. Whenever useful for the particular application, the planar interconnects may have a protruding “lug portion” that projects beyond the outer perimeter side of the other stacked elements, providing an externally contactable area sufficiently large for the power (current rating) of an electrical tap, at an intermediate voltage relative to the voltage difference between the end terminals of the stack, connectable to an external circuit.

Abstract: A static inverter for a battery of elementary, current sources or cells electrically in series and a number N of intermediate voltage taps along the chain of elementary DC current sources, wherein the number of elementary cells comprised between an intermediate tap and another intermediate tap adjacent to it or an end terminal of said chain is proportionate to the amplitude in the respective phase interval of a number N of discretization phases of the waveform of the AC voltage to be output in a quadrant; is implemented by arranging for: a number N of power switches each connecting a respective intermediate tap and a first end terminal of a first polarity of said chain of elementary cells in series to a common circuit node of said first polarity; an output bridge stage constituted by at least four power switches controlled in pairs for switching the current paths through the bridge stage, having a first pair of nodes coupled to said common circuit node of said first plurality and to the other end terminal of

Abstract: A method of storing electric energy from an AC source of a certain frequency, whose value is not pre-established and is even variable, in one or more redox batteries composed of a plurality of elementary cells electrically in series and having a certain cell voltage, is disclosed. The method is implemented in an outstandingly versatile system for storing energy in one or more redox batteries easy to realize and capable of storing energy in a redox battery in highly efficient manner independently of the electric characteristics with which it is generated, and capable of exploiting the redox battery even as a “buffer” for transforming energy from an electrical source of certain voltage and frequency characteristics for supplying it to a load or outputting it on the electricity distribution network at different electric characteristics.

Abstract: A static inverter for a battery of elementary, current sources or cells electrically in series and a number N of intermediate voltage taps along the chain of elementary DC current sources, wherein the number of elementary cells comprised between an intermediate tap and another intermediate tap adjacent to it or an end terminal of said chain is proportionate to the amplitude in the respective phase interval of a number N of discretization phases of the waveform of the AC voltage to be output in a quadrant; is implemented by arranging for: a number N of power switches each connecting a respective intermediate tap and a first end terminal of a first polarity of said chain of elementary cells in series to a common circuit node of said first polarity; an output bridge stage constituted by at least four power switches controlled in pairs for switching the current paths through the bridge stage, having a first pair of nodes coupled to said common circuit node of said first plurality and to the other end terminal of