Fan-shaped flow cell, fan-shaped flow cell stack and circular flow cell stack

Abstract

The invention provides a fan-shaped flow cell, a fan-shaped flow cell stack and a circular flow cell stack. The fan-shaped flow cell comprises a fan-shaped ion exchange membrane and a fan-shaped half cell. The half cell comprises a anode half cell and a cathode half cell, the anode half cell and the cathode half cell are oppositely arranged on two sides of the ion exchange membrane, the anode half cell and the cathode half cell are respectively provided with fan-shaped electrolyte inlets and fan-shaped electrolyte outlets, the electrolyte inlets are arranged close to the long arc edges of the half cells, the electrolyte outlets are arranged close to the short arc edges of half cells, and arc length of the electrolyte inlets is larger than that of the electrolyte outlets. The arc length of the electrolyte inlets of the fan-shaped flow cell is larger than that of the electrolyte outlets of the fan-shaped flow cell, therefore entering linear speed of electrolyte is less than flowing-out linear speed of the electrolyte. During charge and discharge, reaction ion concentration is decreased, and reaction zone is decreased along the flow direction of the electrolyte. Required ions are reduced, concentration polarization is reduced, and charge-discharge efficiency is improved.

Description

technical field [0001] The present invention relates to the field of flow batteries, in particular to a fan-shaped flow battery, a fan-shaped flow battery stack and a circular flow battery stack. Background technique [0002] The existing flow battery stack includes a flow frame 1', a bipolar plate 2', a porous electrode 3', and an ion exchange membrane 4' according to figure 1 Stacked and assembled in the order shown, the battery stack consists of figure 1 The structure shown in is stacked repeatedly, consisting of figure 1 with figure 2 It can be seen that the single battery sheet is rectangular, the electrolyte inlet is at one end of the rectangle, and the outlet is at the other end of the rectangle. No matter how the internal flow field of the battery is designed, the electrolyte will gradually flow from one end of the battery sheet to the other end, resulting in uneven reaction of the electrolyte in the battery sheet. Moreover, in the flow process, when charging an...

AI Technical Summary

Problems solved by technology

No matter how the internal flow field of the battery is designed, the electrolyte will gradually flow from one end of the cell to the other, resulting in uneven reaction of the electrolyte in the cell

Moreover, in the flow process, when charging and discharging, the reactant ion concentration of the electrolyte at the inlet end is greater than the reactant ion concentration at the outlet end, and with the flow of the electrolyte and the consumption of the reactant ions, the reactant ion concentration gradually decreases; therefore, There is a certain difference in the reaction ion concentration of the electrolyte at the inlet and outlet, and the linear velocity of the electrolyte passing through the porous electrode at the inlet and outlet is the same (due to the design of the rectangular cell, the cross-sectional area of ​​the inlet and outlet is equal and the volume flow rate of the inlet and outlet is constant. equal), which further exacerbates the uneven reaction of the electrolyte, the concentration polarization and the reduction of battery efficiency

Images