Large format lithium ion pouch cell full thermal characterisation for improved electric vehicle thermal management

JOURNAL OF POWER SOURCES

卷:359

Article

Grandjean, Thomas¹  Barai, Anup¹  Hosseinzadeh, Elham¹  Guo, Yue¹  McGordon, Andrew¹  Marco, James¹ 

[1] Univ Warwick, WMG, Coventry CV4 7AL, W Midlands, England

关键词: Lithium ion;    Temperature gradient;    Thermal management;    Thermal characterisation;    Battery thermal management system;   

DOI  :  10.1016/j.jpowsour.2017.05.016

来源: Elsevier

【 摘 要 】

It is crucial to maintain temperature homogeneity in lithium ion batteries in order to prevent adverse voltage distributions and differential ageing within the cell. As such, the thermal behaviour of a large-format 20 Ah lithium iron phosphate pouch cell is investigated over a wide range of ambient temperatures and C rates during both charging and discharging. Whilst previous studies have only considered one surface, this article presents experimental results, which characterise both surfaces of the cell exposed to similar thermal media and boundary conditions, allowing for thermal gradients in-plane and perpendicular to the stack to be quantified. Temperature gradients, caused by self-heating, are found to increase with increasing C rate and decreasing temperature to such an extent that 13.4 +/- 0.7% capacity can be extracted using a 10C discharge compared to a 0.5C discharge, both at -10 degrees C ambient temperature. The former condition causes an 18.8 +/- 1.1 degrees C in plane gradient and a 19.7 +/- 0.8 degrees C thermal gradient perpendicular to the stack, which results in large current density distributions and local state of charge differences within the cell. The implications of these thermal and electrical inhomogeneities on ageing and battery pack design for the automotive industry are discussed. (C) 2017 Elsevier B.V. All rights reserved.

【 授权许可】

Free