Effect of Ball-Milling on 3-V Capacity of Lithium−Manganese Oxospinel Cathodes

• Published in: Chemistry of materials Vol. 13; no. 5; pp. 1758 - 1764
• Main Authors: Kang, Sun-Ho, Goodenough, John B, Rabenberg, Llewellyn K
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 21.05.2001
• Subjects: Applied sciences; Direct energy conversion and energy accumulation; Electrical engineering. Electrical power engineering; Electrical power engineering; Electrochemical conversion: primary and secondary batteries, fuel cells; Exact sciences and technology; Ternary compound; Scanning electron microscopy; Ball mill; Lithium Oxides; Lithium batteries; Secondary cell; Electrode material; Fabrication property relation; X ray diffraction; Discharge charge cycle; Surface structure; Mechanical treatment; Transmission electron microscopy; Spinels; Morphology; Manganese Oxides; Specific capacity; Electrical characteristic
• ISSN: 0897-4756; 1520-5002
• DOI: 10.1021/cm000920g

Ball-milling for a sufficient period of time of lithium−manganese oxide spinels, prepared either by a sol−gel method or by solid-state reaction, gave cathode materials of a lithium cell with excellent capacity retention in the 3-V range at room temperature and elevated temperatures despite an apparent Jahn−Teller distortion. In a 50-cycle test with 0.5 mA/cm2, a sample ball-milled for 1 h gave a constant capacity of 122 mAh/g at a constant voltage 2.9 V versus lithium. X-ray diffraction and transmission electron microscopy were performed on the ball-milled spinel powders; they were found to contain significant strain and to consist of nanometer-scale grains. Furthermore, partial oxidation of manganese ions took place during the ball-milling process.