Open AccessMeasuring Irreversible Heat Generation in Lithium-Ion Batteries: An Experimental Methodology
Author(s) -
Laura Bravo Diaz,
Alastair Hales,
M. Waseem Marzook,
Yatish Patel,
Gregory J. Offer
Publication year - 2022
Publication title -
journal of the electrochemical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.258
H-Index - 271
eISSN - 1945-7111
pISSN - 0013-4651
DOI - 10.1149/1945-7111/ac5ada
Subject(s) - heat generation , lithium (medication) , thermal , nuclear engineering , battery (electricity) , power density , materials science , ion , thermal conductivity , electricity generation , lithium ion battery , thermodynamics , mechanical engineering , process engineering , power (physics) , chemistry , composite material , physics , engineering , medicine , organic chemistry , endocrinology
Lithium-ion battery research has historically been driven by power and energy density targets. However, the performance of a lithium-ion cell is strongly influenced by its heat generation and rejection capabilities which have received less attention. The development of adequate thermal metrics able to capture the anisotropic thermal conductivity and uneven internal heat generation rates characteristic of lithium-ion cells is therefore paramount. The Cell Cooling Coefficient (CCC), in W.K −1 , has been introduced as a suitable metric to quantify the rate of heat rejection of a given cell and thermal management method. However, there is no standardised methodology defining how to measure the heat generation capabilities of a cell. In this study, we applied the CCC empirical methodology to evaluate the rates of irreversible heat generation at various operation conditions, providing maps which give a complete insight into cell thermal performance. The maps derived show how the most important operational variables (frequency, C-rate, SOC and temperature) influence the cell thermal performance. These maps can be used along with the CCC by pack engineers to optimise the design of thermal management systems and to down select cells according to their thermal performance.