Quantifying the Effect of Separator Thickness on Rate Performance in Lithium-Ion Batteries. Issue 3 (1st March 2022)

• Record Type: Journal Article
• Authors: Horváth, Dominik V.; Tian, Ruiyuan; Gabbett, Cian; Nicolosi, Valeria; Coleman, Jonathan N.
• Is Part Of: Journal of the Electrochemical Society. Volume 169:Issue 3(2022)
• Publication Date: 2022-03-01
• Subjects: Electrochemistry -- Periodicals; 541.3705
• DOI: 10.1149/1945-7111/ac5654
• Languages: English
• ISSNs: 0013-4651

Abstract

Abstract : In addition to improving parameters such as energy density and stability, it is important to maximise rate performance in lithium-ion batteries. While much work has focused on rate-limiting factors associated with the electrodes, much less attention has been paid to the effect of the separator on rate-performance. Here we perform a quantitative study on the effect of separator thickness on the rate-performance of a model system of NMC-based half cells. By fitting experimental capacity vs rate curves, we measured the characteristic time associated with charge/discharge as a function of separator thickness, finding a roughly linear increase for separator thicknesses below ∼65 μ m. This behaviour is consistent with a simple physical model which shows the separator thickness dependence to be dominated by electrolyte resistance effects. The predictions of the model match the data extremely well with no adjustable parameters.