Li-ion batteries (LIBs) employ porous, composite-type electrodes, where few weight percentages of carbonaceous conducting agents and polymeric binders are required to bestow electrodes with electrical conductivity and mechanical robustness. However, the use of such inactive materials has limited enhancements of battery performance in terms of energy density and safety. In this study, we introduced graphene/polyvinylidene fluoride (Gr/PVdF) composites in Ni-rich oxide cathodes for LIBs, replacing conventional conducting agents, carbon black (CB) nanoparticles. By using Gr/PVdF suspensions, we fabricated highly dense LiNi_0.85Co_0.15Al_0.05O₂ (NCA) cathodes having a uniform distribution of conductive Gr sheets without CB nanoparticles, which was confirmed by scanning spreading resistance microscopy mode using atomic force microscopy. At a high content of 99 wt.% NCA, good cycling stability was shown with significantly improved areal capacity (Q_areal) and volumetric capacity (Q_vol), relative to the CB/PVdF-containing NCA electrode with a commercial-level of electrode parameters. The NCA electrodes using 1 wt.% Gr/PVdF (0.9:0.1) delivered a high Q_areal of ~3.7 mAh cm⁻² (~19% increment) and a high Q_vol of ~774 mAh cm⁻³ (~18% increment) at a current rate of 0.2 C, as compared to the conventional NCA electrode. Our results suggest a viable strategy for superseding conventional conducting agents (CB) and improving the electrochemical performance of Ni-rich cathodes for advanced LIBs.

Lithium is a promising anode material for advanced batteries because of its high capacity and low redox potential. However, its practical use is hindered by nonuniform Li deposition and dendrite formation, leading to safety concerns in Li metal batteries. Our study shows that Ag-based materials enhance the uniformity of Li deposition on Ag-modified Li (AgLi) surfaces, thereby addressing these key challenges. This improvement is due to the strong affinity of Ag for Li, which promotes uniform deposition and dissolution. Additionally, the AgLi surface demonstrated an improved cycling stability, which is crucial for long-term battery reliability. Emphasizing our analytical approach, we utilized comprehensive techniques such as Kelvin probe force microscopy (KPFM) and electrochemical atomic force microscopy (EC-AFM) to locally analyze the electrical properties and unravel the Li deposition/dissolution mechanisms. KPFM analysis provided crucial insights into surface potential variations, while EC-AFM highlighted topographical changes during the Li deposition and dissolution processes, contributing significantly to the development of safer and more efficient Li metal batteries.