As the world transitions to electric vehicles and greater electrification, so does the need for new, innovative solutions that support battery manufacturing. Henkel offers a wide portfolio of solutions for all battery pack designs, including conductive electrode coatings. Conductive electrode coatings are critical to the performance, stability, and safety of lithium batteries.
Conductive Coatings
Conductive coatings, also known as conversion coatings, are composed of thin films of various materials and are widely used to improve the performance and longevity of lithium batteries. These coatings are applied to the surface of battery electrodes to facilitate electrochemical reactions, increase stability, and prevent degradation. Conductive coatings serve three primary functions: passivation, protection and interface modification.
Passivation
Passivation refers to a stable and chemically inert layer on the surface of the electrode, most often the anode, that prevents undesirable chemical reactions and degradation processes during charge-discharge cycles. In lithium-ion batteries, the formation of a passivating layer on the surface of graphite anodes is necessary for long-term stability and performance. Conductive coatings help facilitate the formation of passivating layers by providing nucleation sites and controlling the kinetics of solid electrolyte interface (SEI) formation. This process improves the overall efficiency and lifespan of the battery.
Protection
Conductive coatings also serve as protective barriers to prevent unwanted reactions in the battery with electrolyte components, moisture, and other environmental risks. In lithium-sulfur batteries, conductive coatings on sulfur cathodes prevent polysulfide intermediates from dissolving into the electrolyte material, thereby mitigating capacity fading and improving cycling stability. Likewise, conductive coatings in lithium-air batteries suppress the breakdown of electrolytes and formation of damaging reaction products. Conductive coatings therefore extend the operational lifespan of these batteries.
Interface Modification
Conductive coatings play a critical role in modifying the interface properties between the electrolytes and electrode materials. This has a direct influence on ion transport kinetics, charge transfer processes, and overall battery performance. Researchers are customizing the composition, morphology, and surface chemistry of conductive coatings to promote rapid ion diffusion, improve electronic conductivity, and lower interface resistance. These improvements result in better rate capability, higher energy density, and increased cycling stability in lithium batteries.
Graphite Coatings
Graphite conductive coatings are a cost-effective solution that can be applied via scalable manufacturing processes, making them well suited for large-scale production of lithium batteries. Graphite coatings also offer performance benefits to lithium batteries, including improving cyclability for long-term stability, better rate capability to enable higher power densities, and enhancing mechanical stability to increase battery lifespan and improve performance. These coatings can be tailored to meet the unique requirements of commercial battery production, allowing for consistency, quality, and cost-efficiency.
Water-based, graphite dispersion that is suitable for use as a conductive coating in lithium batteries
BONDERITE® S-FN 109B
Dispersed graphite in resin that provides durable and flexible protective coating for lithium battery electrodes
Henkel continues to research and develop innovative electrode conductive coatings that have the potential to further advance the capabilities of lithium batteries and emerging technologies. Contact us today to speak with a technical representative and find your solution.
