An Online Monitoring Method for Lithium Iron Phosphate Batteries Based on Matlab Model

Abstract This article will mainly introduce a real-time monitoring method based on the equivalent circuit model of the battery. In this way, we can estimate the equivalent capacitance value and equivalent internal resistance value in the equivalent circuit of the battery, and then compare them with their nominal values to better monitor and judge the working status of the battery. This method has the advantage of being easy to apply to online and real-time systems, and based on voltage and current sensors for protection and control, the system has high accuracy and practicality. The system is independent of changes in load, so this article will take lithium iron phosphate batteries as an example to conduct circuit simulation experiments on the capacitance and equivalent resistance values of the battery’s equivalent circuit in the step-down conversion circuit using the Simulink model. By comparing the calculation results with the simulation results, the state monitoring method was validated, and the feasibility of the method was judged based on its actual error value.