Novel battery thermal management system for electric vehicles with a loop heat pipe and graphite sheet inserts

Performance of an Environmentally Friendly Alternative Fluid in a Loop Heat Pipe-Based Battery Thermal Management System

“…The LHP will act as thermal vector between the battery module and a remote ch connected to the HVAC system already present in the vehicle. The feasibility of this de has been proven by an in-house experimentally validated Lumped Parameter Mode [17], but in this work only the results from the experimental demonstrator will be sented. The evaporator consists of the compensation chamber and the wick: the compensation chamber is a two-phase reservoir that feeds the system with liquid to delay dry-out and sets the working pressure of the device.…”

“…Thanks to Table 1, the heat pipe technology was chosen and, in particular, the Loop Heat Pipe (LHP), which was preferred to standard sintered HP for their ability to transport heat along long lengths. In that work, it was demonstrated that not only can LHP successfully contain the cell maximum temperature during fast charging, but also it can outperform a standard liquid cold plate TMS by giving a 3.6 • C lower maximum temperature [17]. The proposed TMS was able to respect both cell and module temperature requirements as well.…”

“…In a previous work by the Authors [17], a comparison between these technologies was carried out over parameters such as power consumption, weight and encumbrance (both influencing the energy density), cost, maintenance, complexity (number of parts) and cooling performance. The ranking was assigned on a low, medium and high basis and is reported in Table 1.…”

“…One important factor often overlooked is the flammability of the thermal medium, as, for instance, most research on PCM cooling for batteries employs paraffin wax, which is a flammable material [14]. Moreover, in HP, most common working fluids are flammable, such as ethanol, acetone, ethyl alcohol, or electrical conductors, such as water [17]. Similarly, liquid-based TMS used a various range of working fluids, such as water [18,19], an ethylene glycol-water mixture [20,21], and refrigerants (R134a) [22,23], which have issues in of being electrical conductors, flammable, and have very high GWPs (1300), respectively.…”

“…LHPs were only employed twice before in a battery thermal management system, firstly in a work by Putra et al where they applied the device to a single cell [24], then by the current authors [17], with regard to the application of LHPs to a battery module. This would make the present work the third experimental work on the application of LHPs to battery thermal management systems.…”