Predictive Models of Lead Acid Battery State of Charge and Health

Lead acid batteries are the old commercially available rechargeable battery technology. They find application in a range of vehicle starting applications as well as a wide array of deep cycle uses such as grid storage, backup power and deep cycle power on a range of commercial, utility, first responder, and military vehicles. Despite being around for over 100 years, there remains no good way of determining the state of charge and diagnosing a range of potential recoverable and non-recoverable degradation faults. Mainstream proposes to develop a range of predictive models that are based on highly sensitive electrochemical impedance spectroscopy that couples battery state both at open circuit and under load. These models will estimate the real-time state of charge and capacity of the battery. Moreover, these models will be designed to identify several key conditions in the cells; which, if uncorrected, can lead to degradation and failure of the battery. These conditions include surface charge, sulfonation of the electrodes, electrode stratification and corrosion of the current collector grid in the positive electrode. In Phase II, Mainstream will incorporate these predictive models into battery monitoring module to provide feedback on early corrective strategies and provide real-time battery state of charge measurements.