Yuri Glukhoy¹, Peter Ducha², Anna Ryaboy^1
1nanocoating plasma systems inc, Fremont, CA
²Vacuum Parts Supply Co., Santa Clara, CA
Three-dimensional (3D) electrode architectures offer a viable pathway to improving lithium-ion battery (LiB) performance by increasing active material loading while maintaining efficient electrolyte access. In this work, we present a vacuumless, chamber-less atmospheric plasma coating technology for fabricating 3D anodes and cathodes using a focused atmospheric inductively coupled plasma beam. Unlike conventional vacuum-based deposition techniques, this process operates entirely at atmospheric pressure and enables localized, high-precision lamination on complex 3D substrates.
Silicon nanoparticle anodes are fabricated via plasma-assisted build-up printing to form mechanically compliant 3D lattice structures on current collectors, accommodating volumetric expansion during electrochemical cycling. For cathodes, LiFePO_₄ nanoparticles are laminated within the interconnected pore network of commercial needle-punched carbon nanofiber fabrics, producing free-standing, highly conductive 3D cathodes with enhanced ionic and electronic transport pathways. The plasma beam technology, originally developed for coating high–aspect-ratio porous components in semiconductor gas distribution plates, enables deep pore penetration through supersonic neutral species. Subsequent in-pore ionization generates a hollow discharge that capacitively couples with an RF bias, neutralizing Debye-layer charge accumulation at pore entrances and enabling conformal lamination of inner pore walls.
This atmospheric plasma lamination process produces mechanically stable, high-adhesion nanolayers resistant to exfoliation at high active material loadings. The resulting 3D electrodes are expected to deliver higher power density, increased energy density, and improved cycle life. The method has been experimentally validated. Figure 1 illustrates plasma beam penetration into a pore, Figure 2 shows an axial section of laminated pores, and Figures 3 and 4 present SEM images of inner pore walls with a 0.4 mm outer diameter. This work highlights the potential of atmospheric plasma technologies to replace vacuum-based coating systems for conformal coating of complex three-dimensional structures.