The electrochemical properties of Li(NixCoyMnz)O₂ (NCM) materials are decisively determined by the interplay of combined disordering of cations and the relevant chemical/electronic changes.

As a prominent next-generation anode material for high-capacity applications, silicon stands out due to its potential. Crystalline silicon, which offers a higher initial capacity compared to its amorphous counterpart, presents challenges in practical applications due to its poor cycling performance. In this study, we prepared composites of crystalline and amorphous silicon with graphite, assembled pouch-type full cells, and evaluated their suitability for practical use. The material incorporating amorphous silicon demonstrated superior performance at both high and low rates, as well as various temperatures. Additionally, the changes in cell thickness during charge and discharge, i.e., the volume changes in the anode material, are significantly related to cycling performance. We examined the microscopic interactions between silicon and lithium atoms using molecular dynamics simulations. Our observations indicate that lithium migration within amorphous silicon, which has lower activation energy, is much easier than in crystalline silicon. In crystalline silicon, lithium penetration is greatly influenced by the orientation of the crystal planes, resulting in anisotropic volume expansion during lithiation.

The development of novel anode materials for high energy density is required. Alloying Si with other metals is a promising approach to utilize the high capacity of Si. In this work, we optimized the composition of a Si–Ti–Al ternary alloy to achieve excellent electrochemical performance in terms of capacity, cyclability, and rate capability. The detailed internal structures of the alloys were characterized through their atomic compositions and diffraction patterns. The lithiation process of the alloy was monitored using real-time scanning electron microscopy, revealing that the mechanical stability of the optimized alloy was strongly enhanced compared to that of the pure silicon material.