Combining Polyacrylic Acid (PAA) with Single-Walled Carbon Nanotubes (SWCNTs) is currently one of the most effective strategies for stabilizing silicon anodes. While PAA provides the "glue" to handle mechanical stress, the SWCNTs provide the "nervous system" for electrical conductivity.

The PAA's roles are mainly shown here: (1) Hydrogen Bonding: PAA is rich in carboxyl groups (-COOH). These form strong hydrogen bonds with the silanol groups (-Si-OH) naturally found on the surface of silicon particles. (2) High Modulus: PAA is relatively stiff compared to traditional binders. This stiffness helps "corral" the silicon particles, limiting their outward expansion during lithiation. (3) Water Solubility: It is processed in water, making it more environmentally friendly and cheaper than NMP-based binders like PVDF.

The main features and functions of SWCNTs: (1) Flexibility: Unlike carbon black (which is point-to-point), SWCNTs are long, flexible fibers. As silicon particles shrink during discharge, the "nanotube bridges" stay connected even if the particles move apart. (2) Aspect Ratio: Because SWCNTs have a massive length-to-diameter ratio, they form a percolating conductive network at very low concentrations (often <1%). (3) Mechanical Reinforcement: They act like rebar in concrete, toughening the PAA matrix and preventing the binder from cracking under the 300% volume expansion stress.

Notes: Please try to store the PAA/SWCNTs composite binder dispersion in a dry place (glovebox is the best option). 

References: 

1. F. Li, et al. A 3D flexible conductive network skeleton by SWCNT-COOH and PVA-PAA enabling high performance for Si anode, Chem. Engineering J., 2024, 499, 156644.
2. L. Zhong, et al. Integrating π-Conjugated and Flexible Alkyl Side Chains via P3HT Incorporation into PAA Binder for High-Performance Silicon Anodes, ACS Appl. Energy Mater. 2025, 8, 20, 15304–15316.