Solvent–Binder Engineering for a Practically Viable Solution Process for Fabricating Sulfide-Based All-Solid-State Batteries
The commercial viability of sulfide all-solid-state batteries (ASSBs) has been hindered by limited solvent compatibility in solution processing as sulfide solid electrolytes (SEs) degrade in polar solvents. This constraint significantly restricts binder selection, which is critical for both performance─particularly at low pressures─and processability. This study addresses this critical issue by investigating thermoplastic polyurethane (TPU) as a binder dissolved in 1,6-dichlorohexane (DCH), a solvent specifically tailored for sulfide ASSBs. TPU demonstrates outstanding adhesion properties in composite anode, cathode, and SE layers, which not only enhance the long-term cycling performance but also enable double-cast solution processing with minimal binder content for electrode-SE layer manufacturing. A silicon-graphite (Si-Gr)-based pouch-cell fabricated through this solution process maintained 80% capacity retention over 100 cycles under practical conditions (40 μm SE layer, 25 °C, and 2 MPa), validating its practical feasibility. The successful implementation of this optimized solvent–binding system for solution processing represents a significant advancement toward practical ASSB technologies.
Authors
- Taeyong Lee (ORCID: https://orcid.org/0000-0002-0176-0525)
- Seung Ho Choi (ORCID: https://orcid.org/0000-0002-3114-0095)
- Inwoo Kim (ORCID: https://orcid.org/0000-0003-1442-0236)
- Jihoon Oh (ORCID: https://orcid.org/0000-0002-3603-6975)
- Dong-Ok Kim (ORCID: https://orcid.org/0000-0002-3358-5995)
- Jang Wook Choi (ORCID: https://orcid.org/0000-0001-8783-0901)
- Jieun Lee (ORCID: https://orcid.org/0000-0003-4227-4125)
- Dong‐Hoon Kim (ORCID: https://orcid.org/0000-0002-0471-9982)
- Heejin Kim (ORCID: https://orcid.org/0000-0003-3027-6983)
- Minkwan Kim (ORCID: https://orcid.org/0000-0002-4079-8219)
- Woo Jun Chung (ORCID: https://orcid.org/0009-0009-9305-3729)
- Sun-ung Moon
Institutions
- Seoul National University (KR)
- Hyundai Motor Group (South Korea) (KR)
- Energy Storage Systems (United States) (US)
- Bio Pharm Dongsung (South Korea) (KR)
- Korea Electronics Technology Institute (KR)
- Korea Basic Science Institute (KR)
- Korea Institute of Science and Technology (KR)
Publication Details
- Journal
- ACS Energy Letters
- Published
- 2025-05-17
- DOI
- https://doi.org/10.1021/acsenergylett.5c00762
- Citations
- 12
- Primary Topic
- Advanced Battery Materials and Technologies
- Type
- article
- Field-Weighted Citation Impact
- 8.77
Funders
- Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung
- Korea Institute of Machinery and Materials
- National Research Foundation of Korea
- Institute of Engineering Research, Seoul National University