Kinetics of Lead Sulphate Crystal Formation in Lead-Acid Batteries
Mentor 1
Dr. Benjamin Church
Location
Union Wisconsin Room
Start Date
29-4-2016 1:30 PM
End Date
29-4-2016 3:30 PM
Description
Though lead-acid batteries are an older technology, they are still the primary source of electricity for use in automotive applications. With the invention and widespread use of auto start-stop technology, a technology which will automatically shut off the engine at a stop and quickly restart it when the engine is needed, originates problems with respect to the batteries ability to quickly recharge. This issue is known as Dynamic Charge Acceptance (DCA). As the battery is constantly being taxed and not fully recharged, the Lead Sulphate crystals (PbSO4) that form as a reaction product during the discharge of the battery end up undergoing a process known as Ostwald Ripening. This process means that the PbSO4 crystals grow larger with time, which is an undesirable outcome as this reduces the surface area to bulk ratio of the crystals. This in turn means that the reverse reaction becomes more difficult and the larger crystals persist. To combat this process, additives may be used to reduce this coarsening and improve the performance of the battery. This project focuses on improving the DCA by examining the kinetics behind the coarsening of the PbSO4 crystals and subsequently testing a series of additives. To accomplish this goal, a novel test cell is required for easy and repeatable testing of the baseline kinetics and subsequent additives.
Kinetics of Lead Sulphate Crystal Formation in Lead-Acid Batteries
Union Wisconsin Room
Though lead-acid batteries are an older technology, they are still the primary source of electricity for use in automotive applications. With the invention and widespread use of auto start-stop technology, a technology which will automatically shut off the engine at a stop and quickly restart it when the engine is needed, originates problems with respect to the batteries ability to quickly recharge. This issue is known as Dynamic Charge Acceptance (DCA). As the battery is constantly being taxed and not fully recharged, the Lead Sulphate crystals (PbSO4) that form as a reaction product during the discharge of the battery end up undergoing a process known as Ostwald Ripening. This process means that the PbSO4 crystals grow larger with time, which is an undesirable outcome as this reduces the surface area to bulk ratio of the crystals. This in turn means that the reverse reaction becomes more difficult and the larger crystals persist. To combat this process, additives may be used to reduce this coarsening and improve the performance of the battery. This project focuses on improving the DCA by examining the kinetics behind the coarsening of the PbSO4 crystals and subsequently testing a series of additives. To accomplish this goal, a novel test cell is required for easy and repeatable testing of the baseline kinetics and subsequent additives.
