![]() ![]() However, laser structuring with ultra-short pulses technique has the potential of outperforming mechanical structuring if the process is optimized to high precision to reduce residual and waste material, due to reproducibility and lower operational costs. Concerning the implementation in a large-scale battery factory, mechanical structuring is currently considered a processing of choice as it has no surface residuals or waste material. Mechanical and laser structuring methods are compared on the surface of a PVDF/NMP-based cathode. The lignin/water cells investigated herein restore after undergoing rate capability tests (5C), except those with pit structures or ultra-high thickness (>200 μm), due to the extensive crack formation during water evaporation which causes poor mechanical stability. Structuring the half-dried cathode surface with ceramic blades is preferred over a stamp-like silicon wafer, and the line structures are easier to produce with high mechanical stability in comparison to pit structures. The underlying lithium-ion diffusion limitation at current densities higher than 0.2 C is mitigated by creating line structures on the surface of the cathode. At porosities higher than 60%, the electronic conductivity limits the rate capability of the cathode, while for porosities lower than 30%, ionic conduction causes significant ionic polarization and consequently diminishes rate performance. The performance deterioration at high discharge currents is amplified by high mass loading and low bulk porosity. For the first time, we fabricate high-density, thick NMC111 cathode coatings using water as a solvent, and bio-derived kraft lignin as a binder material. Testing results from the same type of powder in different conditions will be compared with each other to find how the extent of moisture affects the powders, while testing results from different powders in the same condition will be compared with each other to find how the amount of Ni content affects moisture impact.The cost and environmental impact of lithium-ion batteries (LIBs) can be reduced substantially by enabling the aqueous processing of cathode materials. Then, we characterized the samples by using X-ray Powder Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), and electrochemical performance test from coin type battery cells. The coating stabilizes the cathode/electrolyte interface. We stored each type of NMC powder under three different conditions: (i) dry glovebox, (ii) 2% moisturized chamber, and (iii) water. In the first cycles, the resistance values of the SEI layer for the uncoated NMC are still below those for the NMC coated. To prove the hypothesis, we selected and investigated various NMC with different Ni contents: (1). Based on literature review, we hypothesized that a high oxidation-state Ni^(3+) in NMC will readily react with moisture to lower its oxidation state into Ni^(2+) and lower the electrochemical capacity of NMC. Although this is a particularly important problem, we still have a lack of fundamental understanding about its failure mechanism. However, the material suffers from performance degradations in contact with moisture in the air. LiNi_x Co_y Mn_(1-x-y) O_2 (NMC) materials with various molar ratios of Ni: Mn: Co is now popular options for cathode materials for its lower cost, less toxicity and higher specific capacity comparing to traditional cathode materials such as LiCoO_2. Much attention has been paid to cathode material since it governs the energy density of LIB. Lithium-ion battery (LIB) are in high demand for portable electronic devices and EV today. ![]()
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