NOVELTY - Reversible storage system comprises: a charge-feed or charge-drain area as positive terminal collector (10); a charge-feed or charge-drain area as negative terminal collector (11); a through-flow electrode with a pumpable dispersion with particles, which store electrical energy; at least one feed line; at least one drain line for the pumpable dispersion; at least one ion-permeable membrane (5) or at least one non-conductive spacer (12) for the separation of positive and negative terminal collectors; and optionally at least one additional reservoir.    USE - The reversible storage system is useful for storing electrical energy.    ADVANTAGE - The reversible storage system: exhibits increased energy densities, reduced production costs; prevents increased internal resistance; and utilizes improved liquid storage medium, thus it is easy to handle.    DETAILED DESCRIPTION - Reversible storage system comprises: a charge-feed or charge-drain area as positive terminal collector (10); a charge-feed or charge-drain area as negative terminal collector (11); a through-flow electrode with a pumpable dispersion with particles, which store electrical energy; at least one feed line; at least one drain line for the pumpable dispersion; at least one ion-permeable membrane (5) or at least one non-conductive spacer (12) for the separation of positive and negative terminal collectors; and optionally at least one additional reservoir, which includes at least one pumpable dispersion, a liquid transport device and connecting device for transporting the pumpable dispersion from the reservoir to at least one feed line and from at least one drain line of the respective through-flow electrode to the electrolyte reservoir. The particles exhibit an average particle size distribution of 1 nm-500 mu m and include Helmholtz double layers, which at least partially store the electrical energy capacitively, and both the charge-feed or charge-drain areas are in contact with the pumpable dispersion, where one of the charge-feed or charge-drain area is contacted with the particles, and is provided such that the charge stored in the inner side of the particles is transferred to this area, and the other charge-feed or charge-drain area receives the counter charge of the shell of the particles. The pumpable dispersion contains particles, which store the electrical energy capacitively and/or chemically. A positive electrode material is contacted with the positive terminal collector and a negative electrode material is contacted with negative terminal collector. Each through-flow electrode includes one of the positive or negative electrode materials in the form of the corresponding pumpable dispersion, which is the electrode material together with the other wall regions of the through-flow electrode and forms (i) the corresponding collector and the ion-permeable membrane or (ii) a cathode- or anode through-flow electrode (4) of at least one feed line and at least one drain line, which are provided instead of non-conductive spacers, with the corresponding positive terminal collector or with the corresponding negative terminal collector. The ion-permeable membrane or a side of the spacer, which is remote from the collector, is not permeable for the particles of the pumpable dispersion but it is permeable for electrolytes. The positive and the negative electrode material are arranged parallel to the ion-permeable membrane, or parallel to the arrangement of the spacers and parallel to each other, and are arranged on opposite flat sides of the ion-permeable membrane or on opposite sides of the arrangement of the spacers such that at least one positive electrode material and at least one positive terminal collector are provided on one side of the ion-permeable membrane or on the same side of the spacer and at least one negative electrode material and a negative terminal collector are provided on the opposite side. The negative terminal collector and the positive terminal collector have an flat configuration with a single outer closed boundary and each contain, with one of their flat sides, against the ion-permeable membrane or the spacers, and the pumpable dispersion is arranged on a side, which is remote from the flat side of the respective collector, which contains against the ion-permeable membrane or against the spacers, where the pumpable dispersion can enter at least partially into the respective collector. INDEPENDENT CLAIMS are also included for:    (1) a positive electrode material or negative electrode material comprising the respective corresponding particles dispersed in a liquid carrier material, where the particles exhibit an average particle size distribution of 1 nM-1 mu m, preferably 1-100 nm;    (2) a dispersion mixture, comprising a positive and a negative electrode material, where the particles having a surface coating and/or dispersion auxiliaries, preferably wetting- or dispersing agents, are equipped for preventing the charge exchange during storage and exhibit positively and negatively charged or to be loaded particles with different size, different density and/or different ferromagnetic properties; and    (3) releasing the electrical energy using energy storage system, comprising transporting at least one, preferably at least a pair of oppositely charged electrode materials in the form of the pumpable dispersion, in the form of electrical energy, which is stored capacitively and/or chemically in the particles, continuously and/or discontinuously by at least one of the through-flow electrode, preferably at least one pair of oppositely charged through-flow electrodes, and discharging the charge by the corresponding positive and/or negative terminal collectors.    DESCRIPTION OF DRAWING(S) - The figure shows a schematic representation of the energy storage system.    Anode through-flow electrode (4)    Ion-permeable membrane (5)    Positive terminal collector (10)    Negative terminal collector (11)    Non-conductive spacer (12)