New methodologies for thermal characterization and thermal management of lithium-ion batteries in electric vehicles

Lithium-ion (Li-ion) batteries are the dominant technology adopted as energy storage in a wide range of applications. Nowadays, Li-ion batteries play a pivotal role in the decarbonization of the world by accelerating clean electrification in the transportation sector. Battery thermal management is a key aspect of Li-ion batteries to ensure safe and efficient performance, as well as a long and reliable lifespan. The active battery thermal management systems (BTMSs) such as air and liquid type thermal management systems are now the most common battery thermal management strategies in electric vehicles (EVs). The hybrid BTMSs combining active methods with passive methods such as phase change materials (PCMs) are promising solutions due to the lower parasitic energy consumption compared to pure active methods. However, the complex structure of hybrid BTMSs requires special attention in the design phase to fulfill the key aspects of a suitable thermal management system, such as lightweight and modularity in design for the further evolution of hybrid BTMSs. Meanwhile, thermal characterization and thermal modeling of batteries are prerequisites for a proper thermal management system design. In this PhD thesis, new methodologies are developed for thermal characterization and thermal management of Li-ion batteries. Firstly, a thermal characterization is conducted on the cell level to determine the thermophysical properties of the battery through a time-saving and cost-efficient methodology. The thermal behavior of the cell and also a 48V battery module is investigated based on the obtained thermal parameters at different operational and environmental conditions. Afterward, a numerical comparison is made between the air type and liquid type thermal management methods for the battery module. Focusing on liquid-based BTMS, a novel liquid cooling plate (LCP) is developed, called hybrid LCP providing a modular and lightweight solution to integrate liquid cooling with PCM, and a proof of concept hybrid LCP is designed and tested by a heating element. Finally, the hybrid LCP is experimentally and numerically investigated for thermal management of the battery module and also compared to a conventional volumetrically equivalent aluminum LCP in terms of parasitic energy consumption.

ISBN:9789464443165

Jaar van publicatie:2022

Toegankelijkheid:Open