Pinheiro José M, Gomes Beatriz Moura, Baptista Manuela C, Braga M Helena
Engineering Faculty, University of Porto, R. Dr. Roberto Frias s/n, 4200-465 Porto, Portugal.
LAETA, Institute of Science and Innovation in Mechanical and Industrial Engineering, R. Dr. Roberto Frias 400, 4200-465 Porto, Portugal.
Molecules. 2025 Jul 15;30(14):2974. doi: 10.3390/molecules30142974.
The growing demand for high-energy, safe, and sustainable lithium-ion batteries has increased interest in nickel-rich cathode materials and solid-state electrolytes. This study presents a scalable wet-processing method for fabricating composite cathodes for all-solid-state batteries. The cathodes studied herein are high-nickel LiNiMnCoO, NMC955, the sulfide-based electrolyte LiPSCl, and alternative binders-polyvinyl alcohol (PVA) and polyisobutylene (PIB)-dispersed in toluene, a non-polar solvent compatible with the electrolyte. After fabrication, the cathodes were characterized using SEM/EDX, sheet resistance, and Hall effect measurements. Electrochemical tests were additionally performed in all-solid-state battery half-cells comprising the synthesized cathodes, lithium metal anodes, and LiPSCl as the separator and electrolyte. The results show that both PIB and PVA formulations yielded conductive cathodes with stable microstructures and uniform particle distribution. Electrochemical characterization exposed that the PVA-based cathode outperformed the PIB-based counterpart, achieving the theoretical capacity of 192 mAh·g even at 1C, whereas the PIB cathode reached a maximum capacity of 145 mAh.g at C/40. Post-mortem analysis confirmed the structural integrity of the cathodes. These findings demonstrate the viability of NMC955 as a high-capacity cathode material compatible with solid-state systems.
对高能量、安全且可持续的锂离子电池需求不断增长，这使得人们对富镍正极材料和固态电解质的兴趣日益浓厚。本研究提出了一种可扩展的湿法工艺，用于制造全固态电池的复合正极。本文研究的正极材料是高镍LiNiMnCoO（NMC955）、硫化物基电解质LiPSCl以及分散在与电解质相容的非极性溶剂甲苯中的替代粘合剂——聚乙烯醇（PVA）和聚异丁烯（PIB）。制备完成后，使用扫描电子显微镜/能谱仪（SEM/EDX）、薄层电阻和霍尔效应测量对正极进行表征。此外，还在包含合成正极、锂金属负极以及作为隔膜和电解质的LiPSCl的全固态电池半电池中进行了电化学测试。结果表明，PIB和PVA配方均产生了具有稳定微观结构和均匀颗粒分布的导电正极。电化学表征表明，基于PVA的正极性能优于基于PIB的正极，即使在1C倍率下也能达到192 mAh·g的理论容量，而PIB正极在C/40倍率下达到的最大容量为145 mAh·g。事后分析证实了正极的结构完整性。这些发现证明了NMC955作为与固态系统兼容的高容量正极材料的可行性。
