Tailor-Made Design of Three-Dimensional Batteries Using a Simple, Accurate Geometry Optimization Scheme.

In the rapidly evolving Internet of Things (IoT) society, the demand for microbatteries with high areal energy density is surging. As a promising strategy to enhance areal energy density, three-dimensional (3D) batteries have attracted attention. The feature of 3D batteries is the decoupling of the electrode thickness from the ion-transport distance through the modification of the spatial arrangement of the positive and negative electrodes beyond the conventional parallel plates configuration.

3D-Microbattery Architectural Design Optimization Using Automatic Geometry Generator and Transmission-Line Model.

Optimization of the 3D battery architecture is crucial to improve the performance of microbatteries. However, such optimization is difficult and time consuming by hand for even experts. In this article, we propose a battery optimization system, which consists of an automatic geometry generator and performance simulators.

Fock-Matrix Corrections in Density Functional Theory and Use in Embedded Mean-Field Theory.

We introduce Fock-corrected density functional theory (FCDFT), a semiempirical minimal-basis method part way between density-functional tight binding (DFTB) and DFT. FCDFT contains DFTB-like Fock-matrix contributions calculated using simple pairwise formulas and Slater-Koster transformations, but it also contains the full Kohn-Sham treatment of Coulombic electrostatics. The resulting method is better suited than either minimal-basis DFT or DFTB for modeling the low-level subsystem in embedded mean-field theory (EMFT), improving upon the former by correcting for basis-set incompleteness and upon the latter by properly accounting for electrostatics.

Embedded mean-field theory.

We introduce embedded mean-field theory (EMFT), an approach that flexibly allows for the embedding of one mean-field theory in another without the need to specify or fix the number of particles in each subsystem. EMFT is simple, is well-defined without recourse to parameters, and inherits the simple gradient theory of the parent mean-field theories. In this paper, we report extensive benchmarking of EMFT for the case where the subsystems are treated using different levels of Kohn-Sham theory, using PBE or B3LYP/6-31G* in the high-level subsystem and LDA/STO-3G in the low-level subsystem; we also investigate different levels of density fitting in the two subsystems.

Organic dicarboxylate negative electrode materials with remarkably small strain for high-voltage bipolar batteries.

As advanced negative electrodes for powerful and useful high-voltage bipolar batteries, an intercalated metal-organic framework (iMOF), 2,6-naphthalene dicarboxylate dilithium, is described which has an organic-inorganic layered structure of π-stacked naphthalene and tetrahedral LiO4 units. The material shows a reversible two-electron-transfer Li intercalation at a flat potential of 0.8 V with a small polarization.

Elimination of Translational and Rotational Motions in Nuclear Orbital Plus Molecular Orbital Theory: Contribution of the First-Order Rovibration Coupling.

The translation- and rotation-free nuclear orbital plus molecular orbital (TRF-NOMO) theory was developed to determine nonadiabatic nuclear and electronic wave functions. This study implemented a computational program for the TRF-NOMO method including first-order rotational terms, which corresponds to rovibronic coupling. Numerical assessments of first-order TRF-NOMO Hartree-Fock as well as second-order Møller-Plesset perturbation methods were carried out for several small molecules.

Elimination of translational and rotational motions in nuclear orbital plus molecular orbital theory.

The nuclear orbital plus molecular orbital (NOMO) theory was developed in order to determine the nonadiabatic nuclear and electronic wave functions. This study presents a formulation to remove the contamination of rotational motion as well as translational motion in the NOMO theory. We have formulated the translation- and rotation-free (TRF)-NOMO theory by introducing the TRF Hamiltonian.