Influence of geometrical manufacturing tolerances on lithium‐ion battery performance
The manufacture of lithium-ion battery cells consists of multiple production processes, all of which have tolerances that can affect cell performance. For battery packs that contain 100s or 1000s of individual cells, ensuring consistency and minimising variation between cells is important for reliability and lifetime. This study uses a numerical battery model to examine the influence of electrode coating thickness, calendering and electrode cutting tolerance on capacity, energy, resistance and voltage relaxation. Results show that electrode cutting tolerance has the largest affect upon cell performance characteristics, with calendering tolerance predominantly affecting the voltage relaxation period. For the simulated cell, the negative electrode coating tolerance mainly affects the cell capacity and energy, whereas the positive electrode coating tolerance has the most significant effect upon voltage relaxation. Multiple simulations were conducted with random tolerances of a Gaussian distribution applied to all processes simultaneously to represent a production run of 1000 cells. The resulting distribution of cell performance values is compared with manufacture datasheets to determine the expected reject rate for different tolerance SDs. For a reject rate of zero, the maximum tolerance SD must be less than 1% but need not be less than 0.5% for the geometrical parameters considered. Findings show that the electrode slitting, cutting and negative electrode coating tolerances require tighter manufacturing tolerance than calendering and positive electrode coating thickness.
- Aeronautical, Automotive, Chemical and Materials Engineering
- Aeronautical and Automotive Engineering
Published inInternational Journal of Energy Research
Pages23824 - 23838
- VoR (Version of Record)
Rights holder© The Authors
Publisher statementThis is an Open Access article published by Wiley under the terms of the Creative Commons Attribution-NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes See more here: https://creativecommons.org/licenses/by-nc/4.0/.