Modified Plett-model for modeling voltage hysteresis in lithium-ion cells

Abstract

Lithium-ion cells, especially anode materials like graphite or silicon, exhibit a charge-direction dependent voltage hysteresis. In literature, several approaches exist to model this effect. This paper aims at showing modifications to the so called Plett-model. It will be shown that the specific slope of the transition between charge and discharge OCV curves can be linked to the slope of the OCV curves themselves. This leads to a significant reduction in measurement and parameterization time. Furthermore, this paper features the application of the improved model to composite electrodes. The separation of the contributions of graphite and silicon leads to an improved modeling of the total voltage hysteresis.