Research On The Thermal Equilibrium Of Battery Thermal Management System Combining Reciprocating Circulating Liquid Cooling And Plant Heat Pipe

In order to cope with the problems of environmental pollution and energy shortage,countries around the world are vigorously developing new energy vehicles.Replacing traditional fuel vehicles with new energy vehicles can optimize the energy structure and reduce pollutant emissions.As an important part of new energy vehicles,electric vehicles have received extensive attention."Battery,motor,electric control" technology is the main reason restricting its development,especially the power battery system as a power source,its safety characteristics and performance greatly affect the safety and use of new energy vehicles,is one of the key issues in the development of electric vehicles.Based on this,this paper studied the effect of a thermal management configuration that combines a plant heat pipe and liquid cooling with a circulating cooling strategy on the thermal uniformity of the power battery system.First of all,this paper studied the heat generation and heat transfer characteristics of lithium-ion battery cells.In Comsol,the lithium-ion battery cell was simulated and analyzed under different charging and discharging conditions,and compared with the experimental temperature data of the cell under the same conditions to verify and obtain the accuracy of the temperature data,which could provide a data basis for the next simulation;Secondly,the thermal characteristics of a company's liquid-cooled battery module under high-rate discharge conditions were studied,and a thermal management scheme based on the combination of plant heat pipe and liquid cooling is proposed.The results showed that the improved thermal management system can reduce the Trise of the battery module by more than 15% and the ?T by more than 50%.The effect was remarkable.However,the improved thermal management scheme based on the combination of plant heat pipes and liquid cooling would cause the temperature difference of a single cell to expand,affecting the temperature uniformity of a single cell.Based on the above research,this paper proposed the parameter optimization design of the plant heat pipe & liquid-cooled thermal management system.The thermal management scheme of arranging plant heat pipes between cells was determined,and the influence of cooling duct on thermal management efficiency was studied through three aspects: thermal characteristic parameters,resistance coefficients,and speed uniformity coefficients;Then,through the orthogonal analysis method,the influence of the plant heat pipe structure parameters on the thermal uniformity of the battery module was explored,and then the better thermal management system configuration scheme is obtained;Then studied the sensitivity analysis of the effect of the coolant reciprocating switching time(?)on the battery module;In order to verify the accuracy of the above research model,this paper used AMEsim to analyze the 1D model of the battery module and compared it with the 3D simulation results.The results showed that the 1D and 3D simulation results were within 5%.Finally,a power battery system model based on the optimized configuration of thermal management was built,and its temperature characteristics under different operating conditions and reciprocating switching time(?)are analyzed.Finally,the reciprocating switching time(?)on the thermal power of the battery system is discussed.Sensitivity analysis of uniformity.