Mathematical model of discharge and charge in rechargeable polymer based lithium-ion battery

Abstract

Shepherd’s model is considered as an improved and simple to-apply battery dynamic model. The experimental nominal parameters of five different capacities of Lithium-ion Polymer battery samples are established from the manufacturer’s datasheets. The discharge and charge dynamics of the battery sample with the highest capacity, 3100 mAh are examined and validated. The clarity to derive the dynamic model parameters from the battery datasheet is a fascinating attribute of this model. The experimental database is utilized to study its dynamic feature and subsequently the dynamic battery model, which describes the relationship between the state of charge, the open circuit voltage and ambient temperature. The model is implemented and simulated by using MATLAB/Simulink tools. The current charge-discharge equations describe the optimized electrochemical activities with sustainable long cycle duration. The temperature model brings under control the aging effect, which plays down on the energy capacity of the battery. A steady load of 5 A is linked to the battery and used in a detail simulation of a direct current machine in determination of load effect. The compatibility of these equations and simulations implies that Shepherd’s model is promising to provide guidelines for the analysis of discharge and charge in rechargeable polymer based lithium-ion batteries. The results show that the model can precisely illustrate the dynamic behavior of the batteries.