Study Of The Phase Change Material-Heat Pipe Coupled Cooling Dystem Of Li-ion Battery For The EV

Electric Vehicle is the car powered by electric energy.For contrast with the normal car,it is more quietly,exhausted less and has higher efficiency.This is why it is more and more popular.Li-ion battery is the energy source of electric vehicle,so the battery's heat dissipation is related to the safety of the EV.This paper researched the temperature of the 38120 cylinder Li-ion battery packs and designed a thermal management system based on Phase Change Material coupled with Heat Pipe.The main research contents and conclusions are summarized as follows:1.Researched the relationship between battery internal resistance and SOC(State of Charge)and temperature,calculated battery's heat generation under different discharge rate.Investigated the temperature rise in battery by experimental and numerical simulation.2.Researched the control of the temperature rise and the temperature difference in battery packs using PCM coupled Heat pipe system.Experimented the battery pack's discharging process under 5C and 2.1C rate.The PCM cooling is much more effectual than natural cooling.When using fan and fin,the PCM and Heat Pipe coupled system discreased the temperature in battery pack more.3.Simulated the PCM cooling system,experimental results and simulation results are in good agreement.Then research the influence of thermal coefficient.Have a result that the increase of thermal coefficient is good for the discrease of the temperature within battery pack,but when the thermal coefficient increased big enough,it will have less influence on temperature.4.Researched the PCM and Heat Pipe coupled system under high temperature environment.Experimented the battery pack's discharging process under 5C,1.1C and 2.1C rate.The experiment shows that the melting point of the PCM is a threshold of the temperature within the battery pack,guaranteed the temperature no beyond than the melting point.And the using of Heat Pipe can discrease the amount of PCM,helping lighten the weight of battery pack.