A Case Study of Liquid Cooling Modeling and Privacy Preserving LQR Design for Safe Management of Lithium-Ion Batteries

As a key component of electric vehicles, the life and safety of lithium-ion batteries are particularly important. How to prevent the thermal runaway of batteries and adjust batteries temperature reasonably are crucial to the daily use of batteries. This paper aims to design a fast and safe liquid cooling control system for lithium-ion batteries. Firstly, a linear electrothermal model is constructed to predict the thermal dynamics of batteries during operation. In order to simplify the calculation of model simulation tools, a resistance-capacitance heat transfer model was established to evaluate the thermal transference changes of batteries. Then, COMSOL multi-physical field simulation was used to simulate the actual heat transfer process of lithium-ion batteries and obtain the correlation coefficient of the thermal production model. The approximate discretization method is used to construct the lithium-ion batteries discretization mathematical model, and the steady state control quantity is obtained by linear quadratic regulator. At the same time, in order to prevent the system from being attacked by the network during operation, the control methods are encrypted. Finally, the simulation results show that the privacy preserving LQR model can ensure that the batteries temperature converges to the predetermined temperature faster and more smoothly in a short time.