Research on Thermal Simulation and Control Strategy of Lithium Battery Energy Storage Systems

This paper comprehensively analyzes the thermal management of lithium-ion batteries, with a specific focus on lithium fluorocarbon batteries. We delve into their operational principles, heat generation mechanisms, and heat transfer mechanisms while establishing a robust thermal mathematical model. We investigate a range of ambient temperatures from 15 °C to 45 °C and surface heat transfer coefficients from 5 W·m−2·K−1 to 20 W·m−2·K−1. Our findings highlight that lower ambient temperatures and higher surface heat transfer rates are conducive to enhanced heat dissipation within the battery cells. To effectively manage thermal performance, we propose an integrated approach comprising radiant heat exchange surfaces, thermal grease, and liquid cold plates. This strategy effectively controls the battery pack’s maximum temperature, maintaining it below 70 °C. We also establish the operational temperature boundaries for the thermal management system, with a lower limit of −15 °C. Furthermore, we demonstrate that incorporating radiant heat exchange surfaces and thermal grease can significantly reduce the battery pack’s maximum temperature, particularly under extreme conditions. At an ambient temperature of 45 °C, our coupled thermal management approach maintains the maximum battery pack temperature at 71.507 °C. This strategy ensures the safety and performance of lithium CFC battery packs over a wide range of ambient temperatures. In addition to passive thermal management, we explore a dynamic thermal control method for the battery pack under varying ambient temperatures. We propose specific liquid cold plate inlet times, optimizing energy consumption in thermal management. For ambient temperatures ranging from −15 °C to 15 °C, the inlet time is 5700s after battery discharge, while for temperatures above 15 °C, it is 2100s.