Journal of Physical Chemistry C
Journal of Physical Chemistry C
5 years ago

Impact of Mg-Doping Site Control in the Performance of Li4Ti5O12 Li-Ion Battery Anode: First-Principles Predictions and Experimental Verifications

Impact of Mg-Doping Site Control in the Performance of Li4Ti5O12 Li-Ion Battery Anode: First-Principles Predictions and Experimental Verifications
HyukSu Han, Kyu Hwan Lee, Seungchul Kim, Taeseup Song, Hyunsu Son, Samuel Boateng, Donghun Kim, Haneol Cho, Kang Min Kim, Minho Lee, Heechae Choi
Li4Ti5O12 (LTO) has attracted tremendous attention as a stationary Li-ion battery anode material due to its excellent stability. However, the poor rate capability caused by the low electrical conductivity limits its practical use. Previously, Mg-doping in LTO has been used to improve the electrical conductivity and electrochemical properties, but the Mg-doped LTO system generally exhibits large anomalies in the electrical properties and capacities, which limits the reliable mass-production of engineered LTO. In this study, on the basis of first-principles calculations and related experiments, we systematically study the effects of charge-compensating point defects of the Mg-doped LTO on the electrical properties. A combination of first-principles calculations with thermodynamic modeling shows that high-temperature annealing under reducing conditions could effectively alter the Mg-doping site from a Ti4+ to Li+ site and increase the electrical conductivity significantly due to reduced electron effective mass and increased carrier concentration. Mg-doped LTO annealed under reducing condition exhibits a significantly improved rate capability compared with that of LTO annealed under air condition. The theoretical-analysis-associated experimental results provide more general design guidelines for the preparation of doped LTO with the promise of further improvements in performance.

Publisher URL: http://dx.doi.org/10.1021/acs.jpcc.7b01475

DOI: 10.1021/acs.jpcc.7b01475

You might also like
Discover & Discuss Important Research

Keeping up-to-date with research can feel impossible, with papers being published faster than you'll ever be able to read them. That's where Researcher comes in: we're simplifying discovery and making important discussions happen. With over 19,000 sources, including peer-reviewed journals, preprints, blogs, universities, podcasts and Live events across 10 research areas, you'll never miss what's important to you. It's like social media, but better. Oh, and we should mention - it's free.

  • Download from Google Play
  • Download from App Store
  • Download from AppInChina

Researcher displays publicly available abstracts and doesn’t host any full article content. If the content is open access, we will direct clicks from the abstracts to the publisher website and display the PDF copy on our platform. Clicks to view the full text will be directed to the publisher website, where only users with subscriptions or access through their institution are able to view the full article.