Kinetic pathways of ionic transport in fast-charging lithium titanate
- 28 February 2020
- journal article
- research article
- Published by American Association for the Advancement of Science (AAAS) in Science
- Vol. 367 (6481), 1030-1034
- https://doi.org/10.1126/science.aax3520
Abstract
Fast-charging batteries typically use electrodes capable of accommodating lithium continuously by means of solid-solution transformation because they have few kinetic barriers apart from ionic diffusion. One exception is lithium titanate (Li4Ti5O12), an anode exhibiting extraordinary rate capability apparently inconsistent with its two-phase reaction and slow Li diffusion in both phases. Through real-time tracking of Li+ migration using operando electron energy-loss spectroscopy, we reveal that facile transport in Li4+xTi5O12 is enabled by kinetic pathways comprising distorted Li polyhedra in metastable intermediates along two-phase boundaries. Our work demonstrates that high-rate capability may be enabled by accessing the energy landscape above the ground state, which may have fundamentally different kinetic mechanisms from the ground-state macroscopic phases. This insight should present new opportunities in searching for high-rate electrode materials.Funding Information
- National Science Foundation Graduate Research Fellowship (DGE 1106400)
- Laboratory Directed Research and Development program at the Brookhaven National Lab (DE-SC0012704)
- Vehicle Technologies Office, of the U.S. Department of Energy (DE-AC02-05CH11231)
- U.S. DOE, Office of Basic Energy Science, Division of Materials Science and Engineering (DE-SC0012704)
This publication has 41 references indexed in Scilit:
- Tracking lithium transport and electrochemical reactions in nanoparticlesNature Communications, 2012
- Kinetics of non-equilibrium lithium incorporation in LiFePO4Nature Materials, 2011
- Chemical Distribution and Bonding of Lithium in Intercalated Graphite: Identification with Optimized Electron Energy Loss SpectroscopyACS Nano, 2011
- The Role of Surface and Interface Energy on Phase Stability of Nanosized Insertion CompoundsAdvanced Materials, 2009
- Microscopic Li self-diffusion parameters in the lithiated anode material Li4+xTi5O12 (0 ≤x≤ 3) measured by 7Li solid state NMRPhysical Chemistry Chemical Physics, 2007
- Ultraslow Li diffusion in spinel-type structured Li4Ti5O12—A comparison of results from solid state NMR and impedance spectroscopyPhysical Chemistry Chemical Physics, 2007
- A Kinetic Two‐Phase and Equilibrium Solid Solution in Spinel Li4+xTi5O12Advanced Materials, 2006
- Ab initio calculation of the intercalation voltage of lithium-transition-metal oxide electrodes for rechargeable batteriesJournal of Power Sources, 1997
- Probing the local structure and bonding at interfaces and defects using EELS in the TEMJournal of Microscopy, 1995
- A Relativistic Equation for Bound-State ProblemsPhysical Review B, 1951