Cooling hybrid/electric vehicle battery module: exploring the thermal potential of single evaporator Loop heat Pipe

ABSTRACT

A novel Loop Heat Pipe (LHP) is developed as passive cooling system for Battery Thermal Management System (BTMS). LHPs are more efficient than traditional heat pipes at transferring heat at larger distances, which is essential for keeping the batteries in a safe and efficient temperature range. The Single Evaporator Loop Heat Pipe (SE-LHP) BTMS is tested on a battery module comprising of twelve 18,650 lithium-ion battery cells. The tests are conducted at various charge and discharge rates (1C, 1.5C, and 2C) and ambient temperatures ranging from 30°C to 45°C. The SE-LHP BTMS significantly reduces the maximum cell temperature compared to a module without BTMS. At an ambient temperature of 35°C, the SE-LHP BTMS attains temperature drops of 15%, 16.4%, and 16.29% during battery charge rates of 1C, 1.5C, and 2C, respectively. The SE-LHP BTMS also increases the discharge capacity of the battery module. For the 1.5C discharge rate, the discharge capacity increases from 41% State of Charge (SOC) to 0% SOC with the SE-LHP BTMS, compared to 39% SOC without BTMS. For the 2C discharge rate, the discharge capacity increases from 59% SOC to 0% SOC with the SE-LHP BTMS, compared to 56% SOC without BTMS. The SE-LHP BTMS also helps to keep even temperature spreading among the battery cells. When the module is exposed to ambient temperatures ranging from 30°C to 45°C, the SE-LHP BTMS keeps a temperature difference of less than 2.43°C and 3.38°C among the battery cells for all charge and discharge rates, respectively.

KEYWORDS:

• BTMS
• EVs
• heat pipes
• lithium-ion battery
• loop heat pipes

Acknowledgements

The research is financially supported by SERB and DST, Government of India, under the Core Research Grant (CRG) scheme. The grant number is CRG/2021/008103. This support has enabled the authors to conduct their research and publish this paper.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the Science and Engineering Research Board [CRG/2021/008103].

Notes on contributors

Milan Vachhani

Mr. Milan Vachhani is a Research Scholar in the Mechanical Engineering Department of Sardar Vallabhbhai National Institute of Technology in Surat, Gujarat, India. He is Dr. Hemant B Mehta’s PhD student. His studies are focused on the Heat pipe family and the Battery Thermal Management System.

Kalpak R. Sagar

Dr. Kalpak R Sagar is an Assistant Professor in the Department of Mechanical Engineering at Shree Guru Gobind Singhji Institute of Engineering and Technology, Nanded, Maharashtra, India. He holds a Ph.D. in Mechanical Engineering from the S.V. National Institute of Technology, Surat India. His research focuses on flow through flow through mini-channel, Passive cooling techniques and energy storage.

Durga Nand Jha

Mr. Durga Nand Jha is an MTech student in the Department of Mechanical Engineering at Sardar Vallabhbhai National Institute of Technology in Surat, Gujarat, India. His studies are focused on the Heat pipe family and the Battery Thermal Management System.

Vipul. M. Patel

Dr. Vipul. M. Patel is an Assistant Professor in the Department of Mechanical Engineering at Sardar Vallabhbhai National Institute of Technology, Surat, India. He holds a Ph.D. in Mechanical Engineering from the Indian Institute of Technology Delhi, India. His research focuses on radiation heat transfer in participating media, radiation therapy, transport phenomena in porous media, heat transfer, and heat pipe-based battery thermal management.

Hemantkumar B. Mehta

Dr. Hemantkumar B. Mehta, an Associate Professor at Sardar Vallabhbhai National Institute of Technology, Surat, India, earned his PhD in Mechanical Engineering from S. V. National Institute of Technology, Gujarat. His research focuses on microscale fluid dynamics, heat transfer, and heat pipe-based battery thermal management. With over 75 publications, a granted patent, and leadership in three sponsored research projects, he’s made substantial contributions to his field. Dr. H. B. Mehta has mentored three Ph.D. scholars and guided 50 MTech students. He’s also a respected life member of the Indian Society for Heat and Mass Transfer (ISHMT).