Safety Characteristics of Chemically Delithiated Cathode Active Materials. (10th December 2015)

• Record Type: Journal Article
• Authors: Aoki, Yasuhito; Yanagisawa, Chika; Nakagawa, Takeshi; Furushima, Yoshitomo; Hasegawa, Yuichi; Oda, Mami
• Is Part Of: ECS transactions. Volume 69:Number 18(2015)
• Page Start: 47
• Page End: 56
• Publication Date: 2015-12-10
• Subjects: Electrochemistry -- Periodicals; Electrochemistry; Periodicals; Electronic journals; Electronic journal; 541.37
• DOI: 10.1149/06918.0047ecst
• Languages: English
• ISSNs: 1938-5862

Abstract

Abstract : Cathode active materials in their charged state are obtained by chemical extraction of lithium, and the thermal and structural stability of cathode active materials alone were evaluated. Oxygen release was detected by TPD-MS and the cause of the oxygen release was assigned to the chemical structural change of cathode active material. During heating process, the surface structural changes were detected by Laser Raman spectroscopy, and the bulk structural changes were detected by XRD. The oxygen release were attributed to the crystallographic change from R3-m to Fd3m at around 270 °C and Fd3m to Fm3m at around 350 °C and the surface structural change started at around 150 °C . It was elucidated that surface decomposition starts 100 °C lower than the bulk decomposition in the charged state.