An advanced solid-state kinetic analysis was used to investigate the thermal decomposition kinetic modeling of the cobalt hydroxide nanoplates synthesized from spent lithium-ion batteries (LIBs). The as synthesized and calcined products were characterized by powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), thermal analysis (DSC-DTA-TGA), and scanning electronic microscopy (SEM). Kinetic analysis showed that complex decomposition of beta-Co(OH)(2) in air occurred through two consecutive reactions in the 120-260 degrees C temperature interval. The reaction mechanism of the whole process can be kinetically characterized by two successive reactions: a phase boundary contracting reaction followed by a Prout-Tompkins autocatalytic equation. Mechanistic information obtained by the kinetic study was found in good agreement with FT-IR and SEM results. (C) 2017 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.