The electric-thermal coupling simulation and state estimation of lithium-ion battery

Abstract

The widespread deployment of electric vehicles is not solely associated with the electrification reform of the transport sector, but also plays an important role in the low-carbon transformation for urban energy systems. As the main energy supply, lithium-ion battery invariably affects the performance, cost and safety of the electric vehicles. Strengthening the energy management of lithium-ion battery system is of great importance and necessity to guarantee its efficiency and safety. In this paper, the prototype simulation systems of the multi-level batteries covering cell, module and pack are built within MATLAB/Simulink platform to estimate and predict their electrical and thermal properties under various environment and working conditions. Moreover, the battery states including state of charge, state of health and state of power are jointly estimated based on the equivalent circuit model and minimalist electrochemical model. The simulation and experimental results show that the prototype simulation system can not only describe the electrical and thermal properties of the battery, but also estimate the battery state with great accuracy, which guarantees the safe and stable operation of the lithium-ion battery system.