Optimization of grid configuration by investigating its effect on positive plate of lead-acid batteries via numerical modeling

- With increasing the discharge rates the ohmic voltage losses become more important.
- A model used to obtain potential and current distributions for high rate discharge.
- 18 different grids with the same weight are designed to optimize design parameters.
- Grid's structure, lug location, wire angles and tapering skewed wires are studied.
- The optimized double-diagonal middle-lug design improves current uniformity by 48%.

With increasing the applications of lead-acid batteries, the demand for efficient, low resistant and inexpensive batteries has increased drastically. As discharge rates increase, ohmic voltage losses in current collecting system become more important. In this study, numerical methods are employed to investigate the effect of grid configuration, lug position, diagonal wire angles and tapering wires towards the plate's lug on the performance of positive electrode of lead-acid batteries via modeling the current and potential distribution through gird wires, active material and adjacent electrolyte to the surface of each grid. 18 distinct grid designs with same weights are designed to achieve this task. The results indicate that double-diagonal configuration offers up to 43% increased current distribution uniformity. It is also shown that locating the lug near the midpoint of the frame, increasing the degree of parallel diagonal wires and tapering the wires towards the lug increases the uniformity of the current distribution up to 14%, 1.6% and 5.6%, respectively. It is noteworthy that manufacturing and practical limitations has been taken into account in this work as well.