Carbon Coated Copper Foil Roll (Hydrophobic Binder) as Aqueous Battery Anode Current Collector, CABACCCCFRHB

Carbon-coated copper foil is a high-performance evolution of the standard anode current collector. It consists of a high-purity electrolytic copper foil (typically 6 um to 12 um thick) that is coated on one or both sides with a sub-micron layer (0.5 um to 2 um) of conductive carbon—typically a mix of carbon black, graphite, or graphene. The carbon coating acts as a "functional bridge" between the metal current collector and the active anode material. Its multifunctional roles are highlighted below:

(1) Drastic Reduction in Contact Resistance: Metal-to-particle contact is often poor. Carbon-coated foil creates an interface where the conductive carbon fills the microscopic valleys of the copper, ensuring a continuous electrical path. This can reduce internal resistance by up to 40%.

(2) Enhanced Adhesion (Peel Strength): The carbon layer provides a rougher, high-surface-area substrate that bonds much more strongly with the anode slurry binders. This prevents "delamination" (peeling) during high-speed manufacturing or long-term cycling.

(3) Corrosion Protection: The carbon layer acts as a chemical barrier. It protects the copper from being oxidized by the moisture in the air or being corroded by the acidic byproducts (like HF acid) that can form in the electrolyte over time.

(4) Buffering Volume Expansion: For next-gen Silicon anodes, which expand significantly during charging, the carbon layer acts as a mechanical buffer. It helps maintain electrical contact even as the silicon particles shift and swell.

References:

1. W. Qin, et al., Enhanced Li-ion battery performance of TiO2 nanoparticle-loaded Li4Ti5O12 nanosheet anode using carbon coated copper as current collector, J. Power Sources, 2020, 479, 229090. 
2. X. Shen, et al., Study on the Application of Carbon-coated Copper Foil as Negative Current Collector for Silicon-based Lithium-ion Batteries, I. J. Electrochem., Soc., 2020, 15, 9013-9023.