Solid‐state lithium (Li)‐metal batteries (LMBs) are garnering attention as a next‐generation battery technology that can surpass conventional Li‐ion batteries in terms of energy density and operational safety under the condition that the issue of uncontrolled Li dendrite is resolved. In this study, various plastic crystal‐embedded elastomer electrolytes (PCEEs) are investigated with different phase‐separated structures, prepared by systematically adjusting the volume ratio of the phases, to elucidate the structure‐property‐electrochemical performance relationship of the PCEE in the LMBs. At an optimal volume ratio of elastomer phase to plastic‐crystal phase (i.e., 1:1), bicontinuous‐structured PCEE, consisting of efficient ion‐conducting, plastic‐crystal pathways with long‐range connectivity within a crosslinked elastomer matrix, exhibits exceptionally high ionic conductivity (≈10−3S cm−1) at 20 °C and excellent mechanical resilience (elongation at break ≈ 300%). A full cell featuring this optimized PCEE, a 35 µm thick Li anode, and a high loading LiNi0.83Mn0.06Co0.11O2(NMC‐83) cathode delivers a high energy density of 437 Wh kganode+cathode+electrolyte−1. The established structure–property–electrochemical performance relationship of the PCEE for solid‐state LMBs is expected to inform the development of the elastomeric electrolytes for various electrochemical energy systems.
This content will become publicly available on January 10, 2025
Solid‐state lithium (Li) metal batteries (LMBs) have been developed as a promising replacement for conventional Li‐ion batteries due to their potential for higher energy. However, the current solid‐state electrolytes used in LMBs have limitations regarding mechanical and electrochemical properties and interfacial stability. Here, a fluorine (F)‐containing solid polymer electrolyte (SPE) having a bi‐continuous structure of F‐containing elastomers and plastic crystals is reported. The trifluoroethyl acrylate‐based SPE (T‐SPE) exhibits high ionic conductivity over 10−3 S cm−1, superior mechanical elasticity, and robust LiF‐rich interphases at both the Li metal anode and the LiNi0.83Mn0.06Co0.11O2cathode. Full cells with thin T‐SPEs and low negative/positive capacity ratios below 0.5 at the high‐operating voltage of 4.5 V demonstrate a high specific energy of 538 Wh kganode+cathode+electrolyte−1and maintain 393 Wh kg−1at a high specific power of 804 W kganode+cathode+electrolyte−1. The F‐containing phase‐separated SPE system provides a powerful strategy for achieving high‐energy and ‐power solid‐state LMBs.
more » « less- NSF-PAR ID:
- 10486154
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Functional Materials
- ISSN:
- 1616-301X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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