Heat Transfer Enhancement of Liquid Cooled Copper Plate with Oblique Fins for Electric Vehicles Battery Thermal Management

Abstract

As the automotive industry progresses, electric vehicles (EV) grow with increasing demand throughout the world. Nickel-metal hydride (NiMH) battery and lithium-ion (Li-ion) are widely used in EV due to their advantages such as impressive energy density, good power density, and low self-discharge. However, the batteries must be operated within their optimum range for safety and good thermal management to enable a longer lifespan, lower costs, and improve safety for EV batteries. The need for a liquid cold plate (LCP) to be used in EV batteries is now highly reliable on the distribution of the required temperature rather than only standard cooling systems. The fins arrangement in the LCP would likewise impact the cooling efficiency of the EV battery. The main objective of this paper is to determine the heat transfer enhancement of liquid cold plate systems with the oblique fin and different types of liquid coolants. In the experimental test, two liquid types are used namely G13 ethylene glycol and distilled water in five steps, 10% ethylene glycol, 100% distilled water, 75% ethylene glycol + 25% distilled water, 50% ethylene glycol + 50% distilled water, and 25% ethylene glycol + 75% distilled water. Three different flow rates have been utilized which are 0.3, 0.5, and 0.7 GPM to maximize the productivity of flowing fluid and heat transferring with the gate door valve. The LCP encompasses the inline configuration of the oblique fin, which is able to enhance the heat transfer rate from the heater to the liquid cold plate. A GPM of 0.7 reached the least surface temperature for the battery in the three different flow levels. The LCP is capable of sustaining the ambient surface temperatures of the batteries just under the permissible 50 °C operating temperature, which indicates that the developed LCP with the oblique fin may perhaps become an effective option for the thermal control of EV batteries.