Stabilized Nickel-Rich-Layered Oxide Electrodes for High-Performance Lithium-Ion Batteries

Next-generation Li-ion batteries are expected to exhibit superior energy and power density, along with extended cycle life. Ni-rich high-capacity layered nickel manganese cobalt oxide electrode materials (NMC) hold promise in achieving these objectives, despite facing challenges such as capacity fade due to various degradation modes. Crack formation within NMC-based cathode secondary particles, leading to parasitic reactions and the formation of inactive crystal structures, is a critical degradation mechanism. Mechanical and chemical degradation further deteriorate capacity and lifetime. To mitigate these issues, an artificial cathode electrolyte interphase can be applied to the active material before battery cycling. While atomic layer deposition (ALD) has been extensively explored for active material coatings, molecular layer deposition (MLD) offers a complementary approach. When combined with ALD, MLD enables the deposition of flexible hybrid coatings that can accommodate electrode material volume changes during battery operation. This study focuses on depositing TiO₂-titanium terephthalate thin films on a LiNi_0.8Mn_0.1Co_0.1O₂ electrode via ALD-MLD. The electrochemical evaluation demonstrates favorable lithium-ion kinetics and reduced electrolyte decomposition. Overall, the films deposited through ALD-MLD exhibit promising features as flexible and protective coatings for high-energy lithium-ion battery electrodes, offering potential contributions to the enhancement of advanced battery technologies and supporting the growth of the EV and stationary battery industries.