Development of integrated all-vanadium redox-flow battery stack
In order to improve the charge and discharge current density of all-vanadium redox flow battery stacks and develop a high-power stack,the bipolar plate,electrode and flow frame are welded into a whole by means of hot melt welding and laser welding to assemble an integrated redox flow battery stack.Compared with the traditional stack,the Ohmic internal resistance of the integrated flow battery stack is reduced from 20.2 mΩ to 12.1 mΩ.This is mainly due to the welding method of the integrated flow battery stack,which reduces the contact internal resistance between the electrode and the bipolar plate.The voltage efficiency of the integrated flow battery stack is 82.8％at a current density of 125 mA/cm2,which is 2.5 percentage points higher than that of the traditional stack.When the current density is 200 mA/cm2,the energy efficiency of the integrated flow battery stack is still greater than 75％.When the electrolyte flow rate exceeds 0.95 m3/h,the energy efficiency of the stack basically does not change,but the discharge capacity,that is,the electrolyte utilization rate,will be further improved.When the discharge cut-off voltage is optimized from 10.0 V to 10.5 V,the voltage efficiency of the integrated stack is increased from 78.4％to 80.0％at a current density of 200 mA/cm2,the electrolyte utilization rate is basically unchanged.
integrated stackcharge and dischargevoltage efficiencydischarge capacityflow battery
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维普
