The temperature has a significant effect on electric vehicle lithium-ion battery

i.e.

higher temperature will reduce the battery discharge efficiency to accelerate the decay of battery life

while lower temperature will reduce the charging efficiency of battery to shorten the electric vehicle mileage. In order to keep the temperature of the battery in the appropriate temperature range

this paper designed a phase change material management system. The phase change material was wrapped on the outside of the battery

and the influence of phase change material on the temperature field of the battery was studied. The results showed that the latent heat of the phase change material was the most important physical parameter

which directly determined the maximum temperature of the battery pack. The bigger the thermal conductivity of the phase change material

the more uniform the temperature distribution of the battery pack. Compared with pure paraffin

the maximum temperature of the battery pack could be reduced by 2℃ by the phase change material with graphite content of about 25%. In winter

a phase change material heat preservation system made the average temperature of the battery pack 8℃ higher than that without the phase change material.