Battery Production Solvent Alternative to NMP - Jeffsol® MEOX

A conventional binder for powdery composite electrodes, poly(vinylidene fluoride) (PVdF), is widely used in commercial lithium-ion electrodes because of its chemical and electrochemical stability and good affinity to the electrode and electrolyte materials. However, coverage of active material surface and adhesive strength of a composite layer onto a current collector are not enough to cope with severe conditions of electrode operation such as high potential or large volume change during a charge-discharge cycle. In addition, N-methyl-2-pyrrolidone (NMP) as solvent to dissolve PVdF binder to prepare electrode slurry is combustible and harmful. Since there has been intensive preference for alternative water-soluble polymer to PVdF binder, we study water-soluble polymers as new binders for lithium-ion cells, being convinced that binder is critical materials to maximize the intrinsic performance of active materials and to modify the negative electrode surface including SEI to suppress undesired side-reactions at graphite electrode [1]. Recently, we extend our work on binder towards cross-linked and natural polymers for negative and positive electrodes for Li, Na, and K batteries. We will present detailed results to realize high-energy electrode performance with new binders such as polyacrylates [2-4], covalently crosslinked polyacrylates [5], branched polysaccharides [6], polyglutamates [7,8], and SBR latex [9]. We will also discuss the mechanism of better performance compared to that for conventional PVdF with characterization data and surface analyses.

Synthesis of polyguanamines from 2-N,N-dibutylamino-4,6-dichloro-1,3,5-triazine with aromatic diamines

Introduction The use of fossil fuels and the resulting greenhouse gas emissions, particularly CO2, have caused significant environmental damage. Rechargeable batteries are attracting attention as a storage application for renewable energy, and the emergence of next-generation rechargeable batteries that exceed the energy density of lithium-ion batteries is eagerly awaited. Aluminum is a promising material for batteries due to its cost-effectiveness, chemical stability in air, safety, and ease of handling. The oxidation of Al is a 3-electron reaction, resulting in a high theoretical volumetric capacity of 8046 mAh cm-3. Therefore, rechargeable aluminum batteries (RABs), which use aluminum as the negative electrode, are considered one of next-generation rechargeable batteries.Graphite has attracted considerable attention as the positive electrode active material in RABs due to its low cost, high stability, excellent electrical conductivity, and high redox potential. As for electrolyte, room temperature ionic liquids (RTILs) such as 1-ethyl-3-methylimidazolium chloride (EMImCl) offer several advantages, including high ionic conductivity, low vapor pressure, non-flammability, a wide potential window. It is known that AlCl3, a Lewis acid, forms a stoichiometric complex, AlCl4 -, with Cl-, a Lewis base, and AlCl4 - forms the dinuclear complex, Al2Cl7 -, with excess Cl-. So, the mixing ratio of AlCl3 to EMImCl (AlCl3/EMImCl molar ratio) will have a significant effect on the composition of RTILs, and the reaction kinetics of the graphite positive electrode. In this study, we investigated the effect of AlCl3/EMImCl ratio on the positive electrode properties. Experimental A slurry was prepared by mixing graphite powder and polyvinylidene fluoride (PVDF) as a binder with N-methylpyrrolidone (NMP), followed by ultrasonication. An appropriate amount of prepared slurry was applied to a Mo foil and dried under vacuum conditions to prepare a graphite positive electrode. In a glove box, AlCl3 and EMImCl were mixed in different molar ratios and stirred until a light-yellow liquid was obtained. Polished aluminum foil was used as the negative electrode. Results and Discussion Figure 1 shows Raman spectra of ionic liquids with AlCl3/EMImCl ratios from 1.1 to 1.9. In each spectrum, peaks assigned to AlCl4 - and Al2Cl7 - in addition to EMIm+ were observed. As the AlCl3/EMImCl ratio increased, the intensity of the AlCl4 - peak at 350 cm-1 decreased and that of the Al2Cl7 - peaks at 310 cm-1 and 430 cm-1 increased. The intensity of AlCl4 - and Al2Cl7 - linearly decreased and increased with an increase in the AlCl3/EMImCl ratio, respectively, indicating the reaction, AlCl4 - + AlCl3 → Al2Cl7 -, proceeds quantitatively.The cyclic voltammogram of the graphite electrode suggest that some couples of redox peaks of graphite were observed in a potential range between 0.5 V and 2.5 V. Each redox peak shifted negatively as the AlCl3/EMImCl ratio increased. Galvanostatic charge-discharge tests at 500 mA g-1 between 0.5 and 2.5 V were performed using Al/graphite cells containing electrolytes with different AlCl3/EMImCl ratios. In each AlCl3/EMImCl ratio, discharge curve with two plateaus was observed. The discharge capacity at the higher plateau voltage for the electrolyte with AlCl3/EMImCl = 1.1 was lower than that for the other electrolytes, while the discharge capacity at the lower plateau voltage was similar to each other. Irrespective of AlCl3/EMImCl ratio, discharge capacity hardly decreased over 100 charge-discharge cycles, while coulombic efficiency decreased with increasing the AlCl3/EMImCl ratio. This study compared the electrochemical properties of graphite in different molar ratios of electrolytes, which may help with future research and practical applications of RABs. Figure 1

Promoting safer and more cost‐effective lithium‐ion battery manufacturing practices, while also advancing recycling initiatives, is intrinsically tied to reducing reliance on fluorinated polymers like polyvinylidene difluoride (PVDF) as binders and minimizing the use of hazardous and expensive solvents such as N‐methyl pyrrolidone (NMP). In pursuit of this objective, olefin‐ and rubber‐based polymers have been investigated as promising alternatives for binder materials in high‐energy Ni‐rich LiNixCoyMnzO2 (NCM, x≥0.8) cathodes for lithium‐ion batteries (LIBs). Alternative binders such as polyisobutylene (PIB), poly(styrene‐butadiene‐styrene) (SBS), nitrile butadiene rubber (NBR), and its hydrogenated version (HNBR) offer versatile solutions. These polymers can be dissolved in industrial solvents, such as toluene, and have been further processed into homogeneous cathode slurries, thus facilitating the manufacturing of high‐energy Ni‐rich NCM cathodes for lithium‐ion batteries. The evaluation of NCM811 cathodes obtained from PIB, SBS, NBR, and HNBR has involved a thorough assessment of their physical and chemical properties, electrochemical performance, and production expenses, compared with NCM811 cathodes based on PVDF. Notably, cathodes employing PIB and HNBR have exhibited outstanding qualities, showcasing high specific capacity and remarkable electrochemical stability akin to PVDF‐based counterparts. Furthermore, the alternative binders′ superior adhesion, elasticity, and thermal stability have facilitated obtaining uniform and mechanically stable cathode films. Furthermore, using toluene, with its low vapor pressure, has significantly reduced energy costs associated with drying processes, thereby enhancing the overall cost‐effectiveness of the NCM811 cathodes.

The global pursuit of carbon neutrality is driving efforts toward environmentally friendly aqueous electrode manufacturing. However, the inherent chemical reactivity of water with cathode materials remains a challenge to achieving this goal. Here, we design a class of aqueous processing solutions based on the kosmotropic effect. Ion hydration shells in the kosmotropic solutions are restructured to form an ordered state of anion–water clusters and to stabilize local hydration structure adjacent to cathode materials. Consequently, interfacial side reactions and structural degradation of Ni-rich cathode materials are mitigated. The kosmotropic solution-processed LiNi0.8Co0.1Mn0.1O2 cathode achieve high specific and areal capacities (≥ 205 mAh g–1 and ≥ 3.7 mAh cm–2) together with stable cyclability, which are comparable to those of commercial N-methyl-2-pyrrolidone (NMP)-processed cathodes. Techno-economic analysis demonstrates that this kosmotropic solution approach reduces energy consumption in battery manufacturing by 46% compared to the NMP-based process, highlighting its practical and sustainable viability.

The rapid evolution of Li-ion battery technologies and manufacturing processes demands a continual update of environmental impact data. The general objective of this paper is to publish up-to-date primary data on battery manufacturing, which is of great importance to the scientific community and decision-makers. The environmental impacts have been calculated and estimated based on publicly available data disclosed under Hungarian government regulations and official decrees. The gate-to-gate energy use, greenhouse gas (GHG) emissions, water consumption, and N-methyl-2-pyrrolidone (NMP) consumption are estimated for three battery factories in Hungary, with a total annual capacity of approximately 100 GWh. The factories use around 30–35 kWh energy per kWh of battery capacity and the associated GHG emissions are around 10 kgCO2eq per kWh of cell production. The water consumption varies considerably among factories, with one plant using 28 L per kWh and the other two using 56 and 67 L per kWh. The specific consumption of NMP was calculated for two factories, resulting in close values of 0.51–0.56 kg per kWh of cell production. As a new approach, we distinguish between global and local GHG emissions related to battery production. The main component of the latter is carbon dioxide from the combustion of natural gas, but the local transport related to the battery factories is also a source of emissions. Our estimations include not only the consumptions required directly for the manufacturing technology, but also those for social purposes (e.g., heating offices), giving a more complete picture of the factory’s environmental impact. We believe that up-to-date primary data are crucial for ensuring transparency and holds significant value for both the scientific community and decision-makers.

Lithium-ion battery (LiBs) technology has become crucial in the last two decades as these batteries show great promise as power sources that can lead us to the electric vehicle revolution. Over the last decade, there has been a growing demand to improve LiBs by achieving high energy/power density and high charge capacities, combined with more sustainable manufacturing processes to reach zero emission mobility targets and decrease environmental pollution problem.[1]State of the art of electrode manufacturing of LiBs has a large environmental impact due to usage of poly(vinylidene difluoride) (PVDF) binder and N-methyl-2-pyrrolidone (NMP) solvent. A comparative life cycle assessment (LCA), studying the impact of the transition from NMP to water, showed substantially reduced emissions of CO2 equivalents for the latter.[2] Most importantly, NMP is a hazardous and teratogenic compound. Therefore, replacing NMP to H2O is one of the solutions towards to sustainable and nontoxic electrode manufacturing. Aqueous processing of the anodes is already state-of-the-art whilst, the cathode has its own challenges to overcome. Ni-rich transition oxide active materials, such as LiNi0.8MN0.1Co0.1 (NMC811), are attractive for high-capacity target applications. NMC811 is actively used as cathode active material in commercial cells which are manufactured with conventional methods. However, aqueous processing of NMC811 is highly challenging.[3] Due to the high reactive surface of the active material, NMC811 reacts with water during the slurry processing, which leads to Li+/H+ exchange.[4] Thus, the slurry has a high pH that can corrode the aluminum foil current collector and cause poor capacity due to Li loss. In this study, we develop the slurry formulation to minimize the adverse effects of the high pH. The striking point of our study is that the aqueous processing of NMC811 is successfully performed in the research pilot line and later transferred to industry scale.Aqueous electrode processing is one route to eliminate the volatile organic component, NMP. Recently, dry coating, using binder fibrillation has drawn the attention of the battery community and industry. Compared to the slurry-based method, dry process can easily fabricate roll-to-roll electrodes with extreme thicknesses and no cracks in the electrode.[5] More importantly, with no drying process, the dry electrode method saves 45% to 47% energy consumption and ∼20% total battery manufacturing cost compared to the slurry-based method. To compare the performance of the dry and wet coating, NMC811 electrodes were also produced via dry processing (twin screw extruder). The performance of the electrodes which are manufactured via wet and dry processing are compared with regard to electrochemical performance. This study gives a broad overview of sustainable cathode manufacturing for LiBs. The challenges of two manufacturing methods on pilot scale are discussed which enlightens sustainable electrode manufacturing.

Medical Corps Promotions and Dental Corps

Effective role of eco-friendly acetyl tributyl citrate in large-scale catalyst-free synthesis of waterborne polyurethanes without volatile organic compounds

A recommended isotropic dipole oscillator strength distribution (DOSD) has been constructed for the ethylene molecule through the use of quantum mechanical constraint techniques and experimental dipole oscillator strength (DOS) data; the DOS data employed are recent experimental results not available at the time of the original constrained DOSD analysis of this molecule. The constraints are furnished by molar refractivity data and the Thomas–Reiche–Kuhn sum rule. The DOSD is used to evaluate a variety of isotropic dipole oscillator strength sums, logarithmic dipole oscillator strength sums, and mean excitation energies for ethylene. Pseudo-DOSDs for this molecule, and for propene and 1–butene, which are based on an earlier constrained DOSD analysis for these molecules, are developed. They are used to obtain reliable results for the isotropic dipole–dipole dispersion-energy coefficients C6, for the interactions of the alkenes with each other and with 47 other species, and the triple-dipole dispersion-energy coefficients C9 for interactions involving any triple of molecules taken from ethylene, propene, and 1–butene.Key words: alkenes, dipole properties, pseudo-states, dipole–dipole and triple-dipole dispersion energies, long-range additive, non-additive interaction energies.

Synthesis and properties of poly(arylene-ether-ketone)s containing a dimethylnaphthalene skeleton in the main chain

Isotropic dipole oscillator strength distributions (DOSDs) have been constructed for the dimethyl, diethyl and methyl–propyl ether molecules through the use of quantum mechanical constraint techniques and experimental dipole oscillator strength data. The constraints are furnished by molar refractivity data and the Thomas–Reiche–Kuhn sum rule. The DOSDs are used to obtain recommended values for a variety of isotropic dipole oscillator strength sums, logarithmic dipole oscillator strength sums, and mean excitation energies for the molecules. Pseudo-DOSDs for the ethers are also constructed and used to obtain reliable results for the isotropic dipole–dipole dispersion energy coefficients for all two-body interactions of the ethers with each other and with fifty other species. In addition reliable results are also obtained for the triple–dipole dispersion energy coefficients for all three-body interactions involving the ethers. 1Dedicated to Anthony Stone, an excellent scientist and friend, on the occasion of his 70th birthday.

Globally reliable dipole oscillator strength distributions (DOSDs) have been constructed for the H2S molecule in its ground state. An adopted DOSD is used to evaluate a variety of dipole oscillator strength sums Sk, logarithmic dipole sums Lk, and mean excitation energies Ik, for H2S; these dipole properties are important in various physical processes. It is also used to obtain reliable results for the dipole–dipole dispersion energy coefficients C6 for the interaction of H2S with itself, and with thirty-nine other atoms and (mostly) molecules, and the triple-dipole dispersion energy coefficient C9 for (H2S)3. A pseudo-DOSD for H2S is presented which facilitates the evaluation of C6's, and in particular C9's.

Dipole oscillator strength distributions, sums, and dispersion energy coefficients for CO and CO 2

In the process of manufacturing the positive electrode coating for lithium batteries, the slow and energy-consuming drying process greatly restricts the shortening of the production cycle and the improvement of energy efficiency of power lithium batteries. The purpose of this paper is to calculate the evaporation rate of N-methylpyrrolidone (NMP) solvent under different drying parameters in the first stage of evaporation and to predict the main energy consumption changes in the drying process in this stage. This research shows that, in the first evaporation stage of lithium battery coating manufacturing, when the inlet wind speed changes at 2∼12m s−1, the evaporation rate of NMP solvent obtained in the coating will change in 1.18 × 10−3 ∼2.88 × 10−3 g min−1 cm−2. For every 1m s−1 increase in wind speed, the energy consumption of electric heating increases by 57.60kW on average.