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Lithium‐ion capacitors (LICs) are considered a promising next‐generation energy storage system with high energy density and power capability. The conductive additive is a passive and indispensable material in deciding the electrochemical performance of an energy storage device during high current charging and discharging processes. The incorporation of a suitable conductive additive into the layers of an electrode improves electronic conductivity. It reduces the internal resistance and polarization of the electrode resulting in the enhanced performance of the charge‐storage system. Herein, recovered graphite (RG) is reported from dead Li‐ion batteries as an excellent conductive additive that can improve the electronic conductivity of the electrode material. Compared with commercial conductive additive acetylene black (AB), the TiO2 anode material with 5% RG delivered a high discharge capacity of 163 mAh g−1 at a current rate of 0.15 A g−1 with a coulombic efficiency of ≈99% after 500 cycles in half‐cell assembly. The fabricated AC/TiO2@5%RG LIC displays an excellent electrochemical performance with a maximum energy density of ≈50 Wh kg−1 at a current density of 0.15 A g−1. Notably, the LIC rendered promising performance at different temperature conditions (0, 10, 25, and 50 °C). [ABSTRACT FROM AUTHOR]

The emerging field of direct recycling for spent Li-ion batteries offers significant advantages, such as reduced energy expenses and minimized secondary pollution, when compared to traditional pyrometallurgical and hydrometallurgical methods. This is due to its direct utilization of the spent cathodes as raw materials. However, efficient harvesting of spent cathode particles remains a challenge. To address this issue, this technical brief is the first to incorporate resonant acoustic vibration technology (RAV) as an efficient method for stripping cathode powders from spent Li-ion batteries. Our findings indicate that RAV-based techniques can achieve a stripping efficiency of up to 92%. A comparative analysis with conventional stripping methods, such as magnetic stirring, sonication, and curling-uncurling, reveals that RAV coupled with heat treatment provides unparalleled scalability and efficiency, eliminating the need for post-processing. Furthermore, the resulting cathode powders retain their original polycrystalline particle structures, with no impurities, such as carbon black or small aluminum fragments detected. These findings highlight the promise of RAV technology for large-scale recovery of electrode powders and its potential role in direct recycling of spent Li-ion batteries. [ABSTRACT FROM AUTHOR]

• 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]

Iron (III) fluoride (FeF 3), characterized by high voltage and high specific capacity and emerges as a promising candidate for the forthcoming generation of cathode materials in lithium-ion batteries. This study employs a novel methodology by introducing Fe3+ sources into hollow acetylene black particles through a vacuum impregnation method. This innovative approach results in the synthesis of a composite material comprising FeF 3 ∙0.33H 2 O encapsulated within hollow acetylene black nanospheres, denoted as the FeF 3 ∙0.33H 2 O @hollow acetylene black nanosphere composite material (FF@HCN). The composite exhibits a shell composed of highly graphitized carbon and a core containing FeF 3 ∙0.33H 2 O particles in the range of 10–20 nm. The proportion of active materials is 75.56 %. The acetylene black has chain-like structure and high specific surface area, significantly enhances the material's conductivity, contributing 74.4 % to the pseudocapacitance at a scan rate of 1 mV s−1. The cavity graphite shell plays a crucial role in restricting the expansion and pulverization decay of FeF 3 ∙0.33H 2 O nanoparticles, thereby markedly improving the cycle stability. The initial capacity of the FF@HCN composite is 224.4 mAh g−1, and after 1000 cycles at 0.1 C , it maintains a capacity of 162.3 mAh g−1, resulting in a capacity retention rate of 72.3 % and decay per cycle of 0.027 %. A composite material comprising FeF 3 •0.33H 2 O encapsulated within hollow acetylene black nanosphere are successfully synthesized by vacuum impregnation. The highly graphitized carbon shell in the yolk-shell structured composite play a key role in constraining FeF 3 •0.33H 2 O particle pulverization and improving charge transfer, which slows down the capacity decay as well as accelerates the reaction kinetics. [Display omitted] • FeF 3.•0.33H 2 O encapsulated within hollow acetylene black nanosphere are successfully synthesized by vacuum impregnation. • The decreasing of particle pulverization significantly slows down the capacity decay as a cathode in lithium ion cell. • A capacity retention rate of 72.3 % after 1000 cycles is achieved. [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]

In this work, three different solvents such as N, N-Dimethylformamide (DMF), N-Methyl-2-pyrrolidone (NMP) and Dimethyl sulfoxide (DMSO) were used to recycle cathode active materials (CAM) from spent lithium ion batteries (LIBs). Both calcination and solvent dissolution processes were used. The cathode active materials recycled from DMF, NMP and DMSO solvent dissolution process were named as CAM 1, CAM 2 and CAM 3, respectively. Initially, cathode electrode cut into small pieces and then baked at 600 °C for 7 h in tube furnace under argon environment. In the send step baked electrode transferred to solvent and then continue reflux reaction 24 h. In the final step the Al foils were separated from the solution and the cathode active material were collected by vacuum filtration and heat treatment. The structure and morphology of the cathode active materials were characterized by using XRD, Raman, SEM and TEM instruments. The SEM morphology shows that PVDF polymer and acetylene black removed from the cathode active materials by calcination and solvent dissolution process. EDAX and mapping shows that CAM 3 is more pure and uniform morphology than CAM 1 and CAM 2 cathode active materials. The elemental analysis shows that CAM 1, CAM 2 and CAM 3 are NMC 532 cathode powder with a chemical formula Li (Ni 5 Mn 3 Co 2) O 2. XRD results show that R3m layered structure with strong crystalline peaks for all three recycled cathode active materials. Raman analysis confirms the presence of metal oxide. • High purity cathode materials were recycled by calcination and solvent dissolution process. • DMF, NMP and DMSO solvent were used for solvent dissolution processes. • Recycled cathode powder is NMC 532 with a chemical formula Li (Ni 5 Mn 3 Co 2) O 2. • R3m layered structure with strong crystalline peaks for recycled cathode active materials. • Globular cage like morphology with 0.2–10 μm particles size distribution. [ABSTRACT FROM AUTHOR]