Solvation Dynamics Controls Charge Transfer in Polymer Lithium Battery Electrolyte

April 26, 2024
Chemical structure of PPM polymer (a) and typical solvation structure of Li+ in PPM represented by the ball-and-stick model (b). Li+ is shown as a blue sphere, the solvation cage is shown as a large transparent sphere and oxygen atoms within the cage are shown in red.

Scientific Achievement

Temporary crosslinks were observed in a polymer lithium battery electrolyte on nanosecond timescale due to coordination of Li+ ions with segments from more than one polymer chain.

 

Significance and Impact

Improved electrolytes may be designed by rapid screening of electrolytic systems looking for the shorter solvation lifetime, hence easier charge transport.

Research Details

  • Quasielastic neutron scattering (QENS) experiments were performed on mixtures of a lithium salt, lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), and a polymer, poly(pentyl malonate) (PPM).
  • Molecular dynamics (MD) simulations corroborated the average time for the solvation dynamics in this material on ~ 1 ns timescale.

Nanosecond solvation dynamics in a polymer electrolyte for lithium batteries
Nature Materials (2024).
DOI:10.1038/s41563-024-01834-y