Toward General Rules for the Design of Battery Electrodes Based on Titanium Oxides and Free of Conductive Additives. Issue 4 (26th February 2014)

• Record Type: Journal Article
• Authors: Alexander, Caleb T.; Kim, Chunjoong; Yaylian, Riley; Cabana, Jordi
• Is Part Of: Energy technology. Volume 2:Issue 4(2014:Apr.)
• Page Start: 383
• Page End: 390
• Publication Date: 2014-02-26
• Subjects: Energy development -- Periodicals; Power resources -- Periodicals; 333.79
• DOI: 10.1002/ente.201300143
• Languages: English
• ISSNs: 2194-4288

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>The functionality of several titanium oxides as active materials in electrodes free of any conductive additive was evaluated and rationalized. Correlations were established between the phase transformation during lithiation and both utilization and durability. Ramsdellite‐type Li₂Ti₃O₇ was found to perform well, enabled by the small, isotropic volume change that accompanies lithium intercalation. In contrast, the anatase and rutile polymorphs of TiO₂ suffered losses, to different extents. Rutile could be fully lithiated, which resulted in a significant reduction of crystallinity. Changes in the voltage profile suggest that an amorphous fraction existed that was mainly responsible for a very stable activity upon subsequent cycling. In contrast, anatase electrodes could not be fully lithiated, probably due to kinetic limitations imposed by the transformation, and underwent severe decay upon cycling. Both utilization and stability could be improved to some extent by mixing this phase with Li₄Ti₅O₁₂, which could provide a mechanically stable scaffold during operation. Our work identifies rules and suggests pathways for the design of high‐energy‐density electrodes based on these phases through the elimination of additives such as high‐surface‐area carbons.</p> </abstract>