The active material is firstly treated with a gelatin solution and then, the adsorbed gelatin controls the deposition of carbon black that led to its uniform distribution in the final composite. reported an innovative method to uniformly disperse carbon black into cathode films 30. Polyethyleneimine 28, sodium dodecylesulphate (SDS) or exadecyltrimethylammonium bromide (CTAB) 29 dispersants were also employed to favor the dispersion of LFP cathode material in aqueous slurries. This non-ionic dispersant was also used for the preparation of aqueous slurries to make LFP electrodes for instance 27. Triton X100 dispersant is one of the most famous and most employed to help making electrodes, it was recently employed for the dispersion of argyrodite solid-state electrolyte in the composition of NMC cathodes 26. Polyacrylate surfactant orotan has been also reported for dispersing carbon black into LiCoO 2 cathode 25. proposed to disperse Super P carbon in polyacrylic acid dispersant with a high-shear mixer and to combine this suspension with a standard binder and LiFePO 4 (LFP) cathode material to make an electrode 24. reported the utilization of polyurethane-based dispersants to increase the dispersion of carbon black slurries 23. For instance, dispersants are widely employed to help dispersing the carbon and the active material in electrode films. Several efforts have been devoted to improve the quality of the electrodes leading to better electrochemical performance. The viscosity of the ink, the nature of carbons 22, binders and active materials, as well as the solvents used for the dispersion strongly impacts the porosity and the roughness of the electrode. However, the most commonly used fabrication technique is the so-called web-coating method or doctor-blading that consists to spread an electrode slurry on a current collector foil 21. Thus, achieving good dispersion of carbon and active material is important in ASSB as well as the removal of basic species at the surface of the NMC material.Įlectrode fabrication can be achieved using different techniques such as three-dimensional printing 7, spin coating 8, paste generating method 9, freeze-casting 10, electrospinning 11, solvent-based electrostatic spray deposition 12, solvent-free dry powder coating 13, pulsed laser deposition 14, sputtering deposition 15, dry painting 16, screen printing 17, filtration 18, extrusion 19 or recently the solvent-free roll-to-roll manufacturing technique 20. Moreover, in ASSB, the ionic and electronic conduction occurs through solid phases, which is accomplished by the continuous percolation of particles across the electrode. The problem is that the additional washing and drying steps add up significant process cost. As these species are detrimental for the stability of the polymer electrolyte in a battery, it is necessary to remove them this may be achieved by additional washing 6. The Ni-rich NMC material contains high surface concentrations of LiOH and Li 2CO 3 originating from the residual Li precursors and reactions with humid air 5. Further, the need for energy storage devices with higher energy density requires high capacity cathode materials, such as Ni-rich Lithium Nickel Manganese Cobalt Oxide (NMC) (LiNi xMn 1−x−圜o yO 2, x ≥ 0.8, y ≤ 0.1) 4. However, all-solid-state batteries (ASSB) are being reconsidered due to their higher energy density and the absence of inflammable liquid electrolyte, which makes them safer 3. Lithium-ion batteries (LIBs) dominate the rechargeable battery market in the portable electronic devices and electric vehicles sector because of their high energy density and long-life 2. The increase in energy demand and environmental concerns has accelerated the development of sustainable energy storage systems 1.
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