Vacuum drying kinetics and energy consumption analysis of LiFePO4 battery powder

Abstract

As a cathode material of Li-ion battery, the lithium-ion ferrous phosphate (LiFePO4 or LFP) is widely used in the automobile industry. The drying process of LFP material influences the battery performance directly. In the paper, the vacuum drying experiment of LFP material was performed with different drying conditions. The moisture ratio and the drying rate curves were also drawn and analyzed. Eight empirical models were applied to fit the experiment data and Modified Page model was selected to analyze the drying kinetics. Meanwhile, the relative effective diffusion coefficient and the activation energy were further calculated on the basis of the Fick's equation and Arrhenius equation. The energy consumption was also discussed at the end of paper. This research can give a reference to the large scale drying of LFP powder, so that the required amount of product can be achieved in a reasonable time and minimal energy cost.