A self-healing plastic ceramic electrolyte by an aprotic dynamic polymer network for lithium metal batteries.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 39562569.
- Also identified by DOI 10.1038/s41467-024-53869-z and PMC identifier 11576998.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Oxide ceramic electrolytes (OCEs) have great potential for solid-state lithium metal (Li<sup>0</sup>) battery applications because, in theory, their high elastic modulus provides better resistance to Li<sup>0</sup> dendrite growth. However, in practice, OCEs can hardly survive critical current densities higher than 1 mA/cm<sup>2</sup>. Key issues that contribute to the breakdown of OCEs include Li<sup>0</sup> penetration promoted by grain boundaries (GBs), uncontrolled side reactions at electrode-OCE interfaces, and, equally importantly, defects evolution (e.g., void growth and crack propagation) that leads to local current concentration and mechanical failure inside and on OCEs. Here, taking advantage of a dynamically crosslinked aprotic polymer with non-covalent -CH<sub>3</sub>⋯CF<sub>3</sub> bonds, we developed a plastic ceramic electrolyte (PCE) by hybridizing the polymer framework with ionically conductive ceramics. Using in-situ synchrotron X-ray technique and Cryogenic transmission electron microscopy (Cryo-TEM), we uncover that the PCE exhibits self-healing/repairing capability through a two-step dynamic defects removal mechanism. This significantly suppresses the generation of hotspots for Li<sup>0</sup> penetration and chemomechanical degradations, resulting in durability beyond 2000 hours in Li<sup>0</sup>-Li<sup>0</sup> cells at 1 mA/cm<sup>2</sup>. Furthermore, by introducing a polyacrylate buffer layer between PCE and Li<sup>0</sup>-anode, long cycle life >3600 cycles was achieved when paired with a 4.2 V zero-strain cathode, all under near-zero stack pressure.