The accelerating electrification of energy systems has positioned lithium-ion batteries (LIBs) as essential for high-efficiency storage. Yet, the surface energetics of Ni-rich layered cathodes remain poorly understood despite their critical role in interfacial stability. Here, inverse gas chromatography (IGC) at infinite dilution quantifies the surface free-energy components of two benchmark cathodes, NCM (LiNi0.95Co0.04Mn0.01O2) and NCMA (LiNi0.95Co0.02Mn0.02Al0.01O2). NCM exhibits amphoteric behavior with dominant Lewis basicity (KA = 1.48, KD = 1.13), whereas Al incorporation in NCMA shifts the surface toward Lewis acidity (KA = 1.64, KD = 0.47), enhancing electrolyte affinity and suppressing interfacial degradation. Additionally, compared to NCM, our findings reveal reduced London dispersive surface energy (γSL) values of NCMA, which reflect a decrease in the density of high-energy adsorption sites and an increased energetic uniformity of the surface, arising from aluminum-induced lattice tightening and surface densification. Full-cell tests at 45 °C confirm this energetic advantage: NCMA delivers 229.8 mAh g-1 with 95% retention after 100 cycles, outperforming NCM (214.6 mAh g-1, 92%). These results establish a direct correlation between surface energy descriptors and high-temperature durability, offering a quantitative framework for designing next-generation Ni-rich cathodes with superior interfacial and electrochemical stability.
Guo et al. (Thu,) studied this question.