Criticality of incorporating explicit in‐situ measurement of temperature‐dependent heat generation for accurate design of thermal management system for Li‐ion battery pack

Li-ion based energy storage devices have highly temperature dependent characteristics such as performance, life-cycle, efficiency and safety. Large temperature gradient within a cell results in thermal stresses and nonuniform current density leading to accelerated degradation. This adversely affects the life cycle of the cell due to capacity and power fade. There are similar issues due to large temperature variation within a battery pack. Operation of Li-ion cell outside the desirable temperature range also leads to lower efficiency, degradation and safety related issues. Different thermal management approaches have been proposed and demonstrated in past. The present work focuses specifically on minichannel based liquid cooling for conducting a parametric study. Minichannels have been found effective in various thermal management applications due to their simple construction and high convective heat transfer. In past, minichannels have been proposed and used in battery thermal management. However, designing of such systems has been somewhat arbitrary without considering various factors and trade-offs involved. There is a lack of rigorous studies for determining various parameters related to thermal management system that would result in adequate thermal management in a cost-effective manner. In the present work, a comprehensive parametric study has been carried out on the minichannel based liquid cooling for thermal management of Li-ion battery pack. A simplified computationally efficient numerical simulation-based approach has been used to conduct parametric study for optimizing the design and operating parameters of the thermal management system.

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Analysis of Heat-Spreading Thermal Management Solutions for Lithium-Ion Batteries

Volume 4: Energy Systems Analysis, Thermodynamics and Sustainability; Combustion Science and Engineering; Nanoengineering for Energy, Parts A and B ◽

10.1115/imece2011-63662 ◽

2011 ◽

Cited By ~ 7

Author(s):

Hussam Khasawneh ◽

John Neal ◽

Marcello Canova ◽

Yann Guezennec ◽

Ryan Wayne ◽

...

Keyword(s):

Thermal Behavior ◽

Thermal Management ◽

Management System ◽

Cooling System ◽

Battery Pack ◽

Li Ion Battery ◽

Thermal Management System ◽

Li Ion ◽

Flexible Graphite ◽

Heat Spreading

The analysis and optimization of thermal performance of Li-ion battery packs are topics of great interest today. Most Li-ion batteries for motive, vehicular, backup power and utility energy storage applications are fitted with a microprocessor-controlled thermal management system including an array of temperature and voltage sensors and an active cooling system. However, as the complexity of the thermal management system increases, so does its weight, volume and parasitic power consumption, all factors that adversely affect the vehicle’s performance. In this sense, an improved thermal management system based on including passive solutions such as phase change materials or heat spreading technologies could decrease the load on active components and ultimately the weight and costs of the system. This paper describes an experimental and simulation study aimed at evaluating the effectiveness of flexible graphite materials for heat spreaders in battery thermal management systems. A commercial Li-ion battery pack for power tools applications was adopted as a case study. The electro-thermal behavior of the battery pack was characterized through combined experimental investigation and 3D FEM modeling to determine the heat generation rate of the battery cells during utilization and to evaluate the thermal behavior of the battery pack. A thermal management solution based on flexible graphite heat spreading material was then designed and implemented. The paper presents a comparative study conducted in simulation to evaluate the improvements in the pack thermal behavior.

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