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Porous TiO2/C nanocomposite shells with high capacity, excellent cycle stability, and rate performance have been prepared. The synthesis involves coating colloidal TiO2 nanoshells with a resorcinol-formaldehyde (RF) layer with controllable thickness through a sol-gel-like process, and calcining the composites at 700 °C in an inert atmosphere to induce crystallization from amorphous TiO2 to anatase and simultaneous carbonization from RF to carbon. The cross-linked RF polymer contributes to the high stability of the shell morphology and the porous nature of the shells. A strong dependence of the capacity on the amount of incorporated carbon has been revealed, allowing the optimization of the electrode structure for high-rate cell performance.

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The crystal structure and electrochemical properties of LiNi1/3Mn1/3Co1/3O2 (NMC) synthesized from a lithium ion battery recovery stream have been studied previously. In this report, we study the Cu impurity effects on NMC in detail. The difference in crystal structures and electrochemical properties were examined for pure and copper impurity included products. Scanning electron microscopy figures show that the precursor particles of NMC are slightly bigger than that of NMC with copper impurity. After undergoing 150 cycles at 2C, X-ray diffraction refinements results show that the lattice parameters for impurity containing NMC and pure NMC change to different extents. Furthermore, due to the minor change of lattice parameters, copper-containing NMC offers a more stable capacity retention compared to pure NMC.

A previously introduced POSSIM (POlarizable Simulations with Second order Interaction Model) force field has been extended to include parameters for small molecules serving as models for peptide and protein side-chains. Parameters have been fitted to permit reproducing many-body energies, gas-phase dimerization energies and geometries and liquid-phase heats of vaporization and densities. Quantum mechanical and experimental data have been used as the target for the fitting. The POSSIM framework combines accuracy of a polarizable force field and computational efficiency of the second-order approximation of the full-scale induced point dipole polarization formalism. The resulting parameters can be used for simulations of the parameterized molecules themselves or their analogues. In addition to this, these force field parameters are currently being employed in further development of the POSSIM fast polarizable force field for proteins.