High performance of nanostructured lead-acid batteries using rGO as additive for negative electrode

Lead-acid batteries (LABs), while widespread, have limitations in terms of capacity, durability, and performance at high charge and discharge rates and high depths of discharge. Currently lead-acid batteries consist of a sequence of plates formed by a lead grid and a porous paste compressed on it. This configuration causes a very low utilization of the active material and promotes the hard sulphation. Almost all the problems encountered in the LABs could be solved by modifying the morphology of the electrodes and, in particular, using nanostructured materials such as proposed in our works. As demonstrated in these works, the use of nanostructured electrodes of PbO2 and Pb permits to obtain very good results in terms of active material utilization and duration under deep-cycling conditions. Nanostructured battery can operate at high C-rates up to 30C for a very high number of charge/discharge cycles. In addition, these batteries have also shown good results over on a wide temperature range and with the use of gel electrolytes. The increase on performance can be attributable to the nanostructured morphology that ensurer a considerable surface area and consequently a high number of reactive sites for redox reactions. In this work we present a 12V lead acid batteries with nanostructured electrodes and using a Pb nanostructured electrode added with reduced graphene oxide (rGO) to improve their performance. This battery was cycled at high C-rate. In particular, we used a C-rate equal to 10C (6 min to complete charge) and imposing a very deep discharge. These cycling conditions are much more stressful in terms of cut-off and charge/discharge rate in comparison to the parameters usually used for commercial batteries. The rGO contributes to better electrical conduction and decreases internal resistance, for higher efficiency during charging and discharging and a decrease in sulfation. Modified batteries exhibit higher specific capacity, longer cycle life, and better reaction to high currents than classic PBAs. The results obtained indicate that the use of rGO is a viable strategy for improving the performance of lead-acid batteries, with possible applications in sectors such as industry and energy storage.