The fabrication process of Li-ion battery electrodes plays a prominent role in the microstructure and corresponding cell performance. Here, a mesoscale particle dynamics simulation is developed to relate the manufacturing process of a cathode containing Toda NCM-523 active material to physical and structural properties of the dried film. Particle interactions are simulated with shifted-force Lennard-Jones and granular Hertzian functions. LAMMPS, a freely available particle simulator, is used to generate particle trajectories and resulting predicted properties. To make simulations of the full film thickness feasible, the carbon binder domain (CBD) is approximated with μm-scale particles, each representing about 1000 carbon black particles and associated binder. Metrics for model parameterization and validation are measured experimentally and include the following: slurry viscosity, elasticity of the dried film, shrinkage ratio during drying, volume fraction of phases, slurry and dried film densities, and microstructure cross sections. Simulation results are in substantial agreement with experiment, showing that the simulations reasonably reproduce the relevant physics of particle arrangement during fabrication.

Local variations of mechanical, structural, transport, and kinetic properties, referred to as heterogeneity can detrimentally affect battery life and performance. Local heterogeneity results in non-uniform current, temperature, state of charge (SOC), and aging. In this work, we introduce a model that combines Newman-type and equivalent circuit submodels to further understand and quantify the effects of electrode inhomogeneities. For modeling purposes, three regions of different microstructural properties are connected in parallel, to represent measured electrode heterogeneity. Multiple cases of heterogeneities, such as non-uniform ionic resistance and active material loading, are studied at different rates of discharge and charge. The results show that higher rates increase non-uniformities of dependent properties such as temperature, current density, positive and negative electrode states of charge, and charge and discharge capacities, especially in the case of charging. In addition, by calculating the overpotential on the negative electrode, it is shown that lithium could plate non-uniformly on the negative electrode during high rates of charge. Finally, a sensitivity analysis is performed to understand the significance of heterogeneity on different properties.

The susceptibility of colistin-resistant clinical isolates of Klebsiella pneumoniae to ceragenins and antimicrobial peptides (AMPs) suggests that there is little to no cross-resistance between colistin and ceragenins/AMPs and that lipid A modifications are found in bacteria with modest changes in susceptibility to ceragenins and with high levels of resistance to colistin. These results suggest that there are differences in the resistance mechanisms to colistin and ceragenins/AMPs.

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