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• Introduces fabrication-scale solvent-free dry electrode process with PTFE binder. • Defines unit process, equipment, intermediate products, and characterization methods. • Interprets the relationship between intermediate products and cell performance. Conventional wet-electrode manufacturing encounters challenges in producing thicker electrodes due to issues related to solvent evaporation. This study introduces a novel method for fabricating solvent-free dry electrodes using polytetrafluoroethylene (PTFE) as a binder, representing a significant advancement in electrode manufacturing processes. By eliminating the use of solvents, this method not only addresses these challenges but also offers a scalable and practical solution for mass production. The process is meticulously structured into sequential unit operations, each specifically tailored for a distinct function, utilizing the distinctive fibrillation properties of PTFE. Intermediate product specifications for each phase are clearly defined, accompanied by a comprehensive analysis of both physical and electrochemical performances. This analysis highlights the influence of varying PTFE contents and properties on the microstructure of the dry electrode. Notably, the study achieves a significant breakthrough with an electrode formulation of NCM811/PTFE/carbon black (CB)/carbon nanotube (CNT) = 96/2.0/1.8/0.2, which demonstrates exceptional discharge rate capability of 80 % at a 0.5 C-rate (5 mA/cm2) under the demanding parameters of 10 mAh/cm2 and 3.8 g/cc. This approach not only enhances the microstructural properties of dry electrodes but also paves the way for environmentally friendly and efficient electrode manufacturing for future energy storage applications. [ABSTRACT FROM AUTHOR]

The development of elastic nanostructured Si-based anodes holds promise for advancing lithium-ion batteries due to the high theoretical specific capacity exhibited by Si. Combining nanostructured Si with C proves to be a successful strategy in addressing the challenges tied to the substantial volume expansion of Si during lithiation. In this work, a novel Si-based anode is fashioned through a simple and universal strategy, integrating Si nanoparticles with 1D nano-carbonaceous fillers (CPPy-NT) featuring nanotubular morphology and N atoms, and a water-based binder (poly(acrylic acid)). CPPy-NT are derived by carbonizing pre-synthesized polypyrrole nanotubes (PPy-NT). A clear correlation is established among the carbonization temperature for CPPy-NT preparation, N content in CPPy-NT, electrical conductivity, and the electrochemical performance of the ensuing Si/CPPy-NT anode. For comparative analysis, the electrochemical properties of the Si-based anode employing Super P (commercial carbon black) or PPy-NT are contrasted with those of Si/CPPy-NT. Notably, the Si/CPPy-NT anode with CPPy-NT bearing the highest amount of graphitic N sites exhibits a substantial improvement in initial charge capacity (approximately 2200 mAh g−1) and enhanced cycling stability. These findings underscore the potential to elevate the electrochemical activity of the C filler by carefully optimizing morphology, conductivity, and the incorporation of an appropriate amount of graphitic N. [Display omitted] • Synthesis of N-containing 1D nano-carbonaceous fillers with tailored properties. • Integration of N-containing 1D nano-carbonaceous fillers in Si-based anodes. • Development of novel Si/C anodes using an environmentally friendly approach. • Beneficial role of N in enhancing the electrochemical properties of Si/C anodes. [ABSTRACT FROM AUTHOR]

High energy and power density are key requirements for next-generation lithium-ion batteries. One way to improve the former is to reduce the binder and conductive additive content. Carbon black is an important additive that facilitates electronic conduction in lithium-ion batteries and affects the conductive binder domain although it only occupies 5–8% of the electrode mass. However, the function of the structure of carbon black on short- and long-range electronic contacts and pores in the electrode is still not clear and has not been systematically researched in detail. In this work, five carbon blacks with different BET surface areas, oil absorption numbers and ordered graphitic carbon content were investigated. It was found that the ratio of disordered amorphous carbon to ordered graphitic carbon in carbon blacks strongly influences the short- and long-range electrical conduction, and the BET surface area highly affects the pore structure and ionic conductivity in the electrode. Its optimum ratio, indicated by the Raman density I D / I G , is 0.93–0.95. The recommended BET surface area was 130–200 m2/g for this experimental range. The results of this study can provide guidance for the screening of carbon blacks in the lithium-ion battery industry. • Ratio of disordered to ordered carbon highly influences the electronic conduction. • BET surface area highly influences the pore structure and ionic conductivity. • Recommended ratio of carbon is 0.93–0.95 indicated by I D / I G of Raman spectroscopy. • Recommended BET surface area is 130–200 m2/g. [ABSTRACT FROM AUTHOR]