Effect of pre-intercalation on Li-ion diffusion mapped by topochemical single-crystal transformation and operando investigation. Academic Article uri icon

abstract

  • Limitations in electrochemical performance as well as supply chain challenges have rendered positive electrode materials a critical bottleneck for Li-ion batteries. State-of-the-art Li-ion batteries fall short of accessing theoretical capacities. As such, there is intense interest in the design of strategies that enable the more effective utilization of active intercalation materials. Pre-intercalation with alkali-metal ions has attracted interest as a means of accessing higher reversible capacity and improved rate performance. However, the structural basis for improvements in electrochemical performance remains mostly unexplored. Here we use topochemical single-crystal-to-single-crystal transformations in a tunnel-structured -V2O5 positive electrode to illustrate the effect of pre-intercalation in modifying the host lattice and altering diffusion pathways. Furthermore, operando synchrotron X-ray diffraction is used to map Li-ion site preferences and occupancies as a function of the depth of discharge in pre-intercalated materials. Na- and K-ion intercalation 'props open' the one-dimensional tunnel, reduces electrostatic repulsions between inserted Li ions and entirely modifies diffusion pathways, enabling orders of magnitude higher Li-ion diffusivities and accessing higher capacities. Deciphering the atomistic origins of improved performance in pre-intercalated materials on the basis of single-crystal-to-single-crystal topochemical transformation and operando diffraction studies paves the way to site-selective modification approaches for positive electrode design.

published proceedings

  • Nat Mater

altmetric score

  • 17.4

author list (cited authors)

  • Luo, Y., Handy, J. V., Das, T., Ponis, J. D., Albers, R., Chiang, Y., ... Banerjee, S.

citation count

  • 0

complete list of authors

  • Luo, Yuting||Handy, Joseph V||Das, Tisita||Ponis, John D||Albers, Ryan||Chiang, Yu-Hsiang||Pharr, Matt||Schultz, Brian J||Gobbato, Leonardo||Brown, Dean C||Chakraborty, Sudip||Banerjee, Sarbajit

publication date

  • March 2024