Theoretical Study on Thermal Management of Lithium-ion Battery Pack with Chiller Plates and Glycol

Abstract

The preferred candidate for Electric Vehicles is the lithium-ion battery due to its outstanding characteristics such as high energy-to-weight ratio, high voltage, good stability, and slow loss of charge when not in use. With all these advantages, fast charging and thermal management of lithium-ion battery packs are typical problems. Temperature rise in the hybrid and electric vehicle battery pack is directly proportional to the magnitude of charge/discharge power and driver demand. This theoretical study pays attention to the liquid cooling of the battery pack with chiller plates concerning higher ambient conditions to reduce the high-temperature excursions. Coolant flows through chiller plates and helps in carrying away the heat from the pack. Two types of coolant, 50% propylene with 50% water and 50% ethylene with 50% water mixture by volume are used in this study. The study reveals that with a 50-50 propylene glycol and water mixture pack temperature is reduced from 30  to 20 °C in 100 seconds while with a 50-50 ethylene and water mixture pack temperature is reduced from 30 to 20 °C in 320 seconds. The study is carried out with  MATLAB/Simulink using an equivalent circuit model with two RC pairs.