Experimental and modeling investigation of thermal behaviour and performance of lithium ion prismatic cells at cold-start temperatures

Abstract

This thesis examines the thermal behaviour of prismatic lithium iron-phosphate (LFP) cells and batteries and the influence of that behaviour on discharge performance under cold-start operating conditions representative of near- and sub-zero temperature driving. The first part of this thesis details the experimental characterization of global and local thermal behavior, and global voltage performance, of prismatic cells at cold-start ambient temperatures. The second part of this thesis applies the characterization data to validate a 0D lumped capacitance model and a 3D thermal-electrochemical coupled model of the cell. The models are then used to investigate the influence and significance of spatial thermal variations on prismatic cell performance.