Structural Study of Electrochemically Obtained Li2+xTi3O7

✍ Scribed by M.E. Arroyo y de Dompablo; A. Várez; F. Garcı́a-Alvarado

• Publisher: Elsevier Science
• Year: 2000
• Tongue: English
• Weight: 314 KB
• Volume: 153
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1006/jssc.2000.8762

✦ Synopsis

Li 2 Ti 3 O 7 , a ramsdellite-type compound, is able to reversibly insert approximately 2.3 lithium ions per formula down to 1 V versus lithium. Both electron and X-ray di4raction techniques show that the electrochemically inserted compounds Li 2؉x Ti 3 O 7 , with x < 2, maintain the ramsdellite structure, although some important microstructural di4erences are observed. For example the compound with x ‫؍‬ 0.55 exhibits an incommensurate modulation (q+ 1 3 c*). On the other hand, for Li 2؉x Ti 3 O 7 with x > 2, a commensurable a;2b;c cell can be proposed. A close structural relationship between the intercalated compounds and host compound, together with the small changes in the basic ramsdellite cell parameters during the intercalation process, is likely at the origin of the good cycling behavior of a lithium cell using Li 2 Ti 3 O 7 as the positive electrode. 2000 Academic Press