Power Capability Prediction of Lithium-Ion Batteries Using Physics-Based Model and NMPC

A model-based battery power capability prediction method is reported to prevent the battery from moving into harmful situations during its operation for its health and safety. The method incorporates a high-fidelity electrochemical-thermal battery model, with which not only the external limitations on current, voltage, and power, but also the internal constraints such as lithium plating and thermal runaway, can be readily taken into account. The online prediction of maximum power is accomplished by formulating and successively solving a constrained nonlinear optimization problem. Due to the relatively high system order, high model nonlinearity, and long prediction horizon, an accurate and computationally efficient scheme based on nonlinear model predictive control is designed.