Anode interface-stabilizing dry process employing a binary binder system for ultra-thick and durable battery electrode fabrication

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Switzerland : 1996), 2025-01, Vol.503, p.158271, Article 158271
• Main Authors: Lee, Juhyun, Son, Chae Yeong, Han, Seungmin, Yang, Subi, Kim, Patrick Joohyun, Lee, Dongsoo, Lee, Jung Woo, Ryu, Won-Hee, Choi, Junghyun
• Format: Article
• Language: English
• Subjects: Dry-processed graphite anode; High-loading; Lithium-ion battery; Polytetrafluoroethylene; Polyvinylpyrrolidone
• ISSN: 1385-8947
• DOI: 10.1016/j.cej.2024.158271

[Display omitted] •We present a PVP/PTFE binary binder system enabling exceptional stability of dry-processed anodes for Li-ion batteries.•The PVP/PTFE binary binder system effectively mitigates PTFE decomposition.•The binary binder system enhances the mechanical properties and cycle stability, leading to a robust SEI formation.•The modified dry-processed anodes demonstrated a high areal capacity of ∼10 mAh cm2 and long term stability for 200 cycles. Polytetrafluoroethylene (PTFE)-based dry process has gained attention in the battery industry owing to their sustainability, cost-effectiveness, and ability to fabricate high loading electrodes. However, the electrochemical instability of PTFE in anodic environments causes significant capacity loss, hindering the development of high-performance dry-processed anodes. In this study, a binary binder system of PTFE and polyvinylpyrrolidone (PVP) is proposed to prevent direct contact between graphite and PTFE, mitigating unwanted interphase evolution. This strategy improves the mechanical integrity of the electrode. It maintains the binding force between the active materials and PTFE binders. PVP also forms a robust inorganic-rich SEI, enhancing Li-ion kinetics and interfacial stability. Consequently, dry-processed graphite with PVP achieved ultra-high loading anodes (∼10 mAh cm−2) with excellent cycle stability over 200 cycles in full cells coupled with LiNi0.8Co0.1Mn0.1O2 cathodes. This paper presents a cost-effective, high-loading electrode fabrication process and an eco-friendly approach for large-scale electrification.