This paper studies the coupling between stress and open circuit voltage in a commercial lithium-ion pouch cell. This coupling is characterized through measurements of a coupling factor, which is defined as the rate of change in voltage with respect to applied mechanical stress. Based on a simple thermodynamic model, this coupling factor is expected to be related to the expansion characteristics of the pouch cell during charging. The expansion characteristics of the pouch cell are compared with measurements of the coupling factors at different states of charge, and are found to be in agreement with the simple thermodynamic model. This work opens the door for the development of mechanical force sensors based on intercalation materials.

Date Published: 5 June 2014
PDF: 8 pages
Proc. SPIE 9115, Energy Harvesting and Storage: Materials, Devices, and Applications V, 91150K (5 June 2014); doi: 10.1117/12.2055152

Published in SPIE Proceedings Vol. 9115:
Energy Harvesting and Storage: Materials, Devices, and Applications V
Nibir K. Dhar; Palani Balaya; Achyut K. Dutta, Editor(s)