Revisiting Polytetrafluorethylene Binder for Solvent-Free Lithium-Ion Battery Anode Fabrication

Batteries

Fengliu Lou¹  Frederik Huld²  Yang Zhang²  Zhixin Yu²  Song Lu²  Camilla Jektvik³ 

[1] Beyonder AS, Stokkamyrveien 30, 4313 Sandnes, Norway;Department of Energy and Petroleum Engineering, University of Stavanger, 4036 Stavanger, Norway;Department of Materials Science, Norwegian University of Science and Technology, 7491 Trondheim, Norway;

关键词: solvent-free;    PTFE;    hard carbon;    anode fabrication;   

DOI  :  10.3390/batteries8060057

来源: DOAJ

【 摘 要 】

Solvent-free (SF) anodes with different carbon materials (graphite, hard carbon, and soft carbon) were fabricated to investigate the stability of different anodes with polytetrafluorethylene (PTFE) degradation. The graphite anode with large volume variation during the charge/discharge process showed poor cycle life performance, while hard carbon and soft carbon with low-volume expansion showed good cycle life. The SF hard carbon electrodes with a high loading of 10.7 mg/cm² revealed good long-term cycling performance similar to conventional slurry-casting (CSC) electrodes. It demonstrated nearly 90% capacity retention after 120 cycles under a current of 1/3 C with LiNi_0.5Co_0.2Mn_0.3O₂ (NCM523) as cathode in coin cell. The rate capability of the high-loading SF electrodes also is comparable to the CSC electrodes. The high stability of SF hard carbon and soft carbon anodes was attributed to its low-volume variation, which could maintain their integrity even though PTFE was defluorinated to amorphous carbon irreversibly. However, the reduced amorphous carbon cannot tolerate huge volume variation of graphite during cycling, resulting in poor stability.

【 授权许可】

Unknown