Numerical and Experimental Study on the Sintering Process of the Raw Materials of Lithium Battery Cathode

Abstract

In this paper, a multiphysics-coupled computational fluid dynamics (CFD) model was developed to simulate the sintering process of lithium battery raw materials (namely, Ni0.8Co0. 1Mn0. 1(OH)2 and LiOH∙H2O mixture, hereinafter referred to as raw materials), transforming them into ternary cathode materials under pure oxygen conditions. The process involves fluid flow, heat and mass transfer, and chemical reactions. A new method which combined steady-state calculation with transient calculation was adopted. Firstly, the steady-state simulation of the whole furnace was carried out, and then the transient simulation of each furnace area is carried out consequently, the heat and mass transfer processes of raw materials in different furnace zones were solved, ultimately achieving the simulation of the entire furnace sintering process. On-site black box experiments were performed to obtain the temperature evolution during the sintering process. Meanwhile, compared with the calculated results of the model, it was found that the average hit rate with an absolute error of less than ± 20 °C above 300 °C can reach 86.9%, confirming the applicability of the model. The multiphysics-coupled CFD model simultaneously solves the oxygen concentration.

Keywords: 811 cathode material sintering, numerical simulation, On-site temperature testing, Chemical reaction