A Mathematical Model For A Soluble Lead–acid Battery

The most important issue with our current energy technology is the dependence on environmental conditions to produce power.To solve this problem a wide range of energy of energy storage devices are being explored for grid-scale energy storage including soluble lead-acid battery.The soluble lead-acid battery is a redox flow cell that uses a single reservoir to store the electrolyte and does not require a microporous membrane.The battery has two inert electrodes and a single electrolyte of lead methanesulfonate,and it is based on the electrode reactions of Pb???in the electrolyte,allowing a simpler design and a substantial reduction in cost.Flow batteries offer a unique solution to grid-scale energy storage as the electrodes are not being part of electrochemical fuel and do not undergo physical and chemical changes during operation,the storage capacity can be increased easily by increasing the capacity of the electrolyte tanks.This study seeks to further understand the mechanism of a soluble lead-acid flow battery using simulation.The effects of varies changes to operating conditions and system configuration can be explored through simulations.A transient two-dimensional model based on conservation principles?mass,momentum and charge?,incorporating the fundamental modes of transport for the charged species and water is developed.this transport model is combined with a global kinetic model for reactions involving lead species.The influences of the electrode shape,electrode gap,applied current density,operating temperature,inlet electrolyte velocity and initial concentration of species on the charge/discharge behavior of the cell are investigated.By analyzing the change of Pb???surface concentration,cell voltage and positive electrode concentration of PbO/PbO₂ in different operating conditions,we find that among various conditions that affect the performance of the soluble lead acid flow battery,operating temperature and current density may be the keys in optimizing a lead-acid flow battery.By investigating the four different electrodes,it is found that in the same working condition the charge voltage of camber is the highest and its voltage drop is the the biggest,the charge/discharge curves of plate electrode and multi-camber electrode are similar,the charging voltage of trapezoid electrode is the lowest and the energy efficiency of trapezoid is the highest.A two-dimensional stationary model is developed to predict the electrochemical behaviour of the cell,the results show that the positive current distribution is almost entirely determined by geometrical effects,with little influence from the hydrodynamic.