Síntese de LiNi0,8Co0,1Mn0,1O2 (NCM811) para aplicação em baterias de íons-lítio

Abstract

In order to promote innovative technologies and encourage the national market in the development of lithium-ion batteries, research into new cathodes and other inputs for batteries is institutionalized. In this context, material synthesis methods for the manufacture of the NCM811 cathode are already established, such as syntheses by solid state reaction and co-precipitation. In order to establish new, low-cost and scalable synthesis routes, the objective of this work will be the synthesis of NCM811 via the polymeric precursor method, also known as Pechini, and hydroxide coprecipitation, in order to promote the formation of powders with high purity, good homogeneity and nanometric particles, as well as evaluating their electrochemical performance in lithium-ion batteries. The synthesis by the Pechini method consists in obtaining a polymeric system through the formation of chelate groups with metallic cations using citric acid, and in the esterification of these with ethylene glycol. This polymeric system is then calcined, allowing the obtaining of fine and homogeneous oxides. The co-precipitation of hydroxides enables the production of powders on a nanometric scale and of high purity through the precipitation of ionic species formed by the dissolution of solids from the cations of interest in a basic medium. The formed precipitate is washed, centrifuged, dried, deagglomerated in a mortar and calcined, giving rise to the desired oxide. Thus, the synthesis of NCM811 and the physicalchemical characterization of the synthesized material by scanning electron microscopy, energy dispersive spectroscopy and X-ray diffraction were carried out in the laboratory of the SENAI Institute of Innovation in Electrochemistry and in the premises of the Federal Technological University of Paraná. Preparation of the suspension of NCM811 and assembly of the cell for electrochemical characterization were carried out. Electrochemical evaluation of the synthesized materials demonstrate appropriated capacity values for application in lithium-ion batteries.