A Novel Strategy to Manage Lithium-ion Cells in Fast Charge/discharge Operations with Model Predictive Control Approach

To prevent safety issues such as thermal runaway, lithium-ion batteries must be constantly monitored. Most thermal management methods are based on designing suitable cooling systems. Also, since the surface temperature is measurable through a sensor, it is considered the main criterion of thermal management. However, in extremely fast charge-discharge operations, the core temperature can be significantly higher than the surface temperature, so the cooling system may not be able to solely maintain the core temperature in the safe range. The objective of this paper is to combine electrical and thermal management and set the core temperature as the main criterion. To achieve that, model predictive control (MPC) is implemented to control the supplied or drawn current of the battery cell and Sigma point Kalman filter (SPKF) is used to estimate model states. The simulation and experimental results indicate that incorporating MPC and nonlinear Kalman filter Estimators can be a novel strategy to simultaneously manage electrical and thermal states. It is also expected that controlling the core temperature in fast charge-discharge operations, may increase the safety and lifetime of the cell.