Alloy Design for Lithium-Ion Battery Anodes

Abstract

A set of guidelines is proposed for designing high-energy-density alloy anode materials. It is first shown that the molar volume of lithium is about 9 mL/mol in a wide variety of lithium alloys and is independent of lithium content. Using this property of lithium alloys, simple relationships between the volumetric energy density and the volumetric expansion of an alloy are derived. These relationships are extremely powerful for designing alloys with the maximum possible energy density for a given electrode-coating performance.

Conductive Polymer Binder-Enabled SiO–SnxCoyCz Anode for High-Energy Lithium-Ion Batteries

“…5,6 Instead of merely emphasizing the high specific capacities of Si-containing anode, recent focus in this field is on the fabrication of a thick and high-loading Si-containing electrode with high energy densities. 7 The drastic volume change of pure Si anode poses formidable challenges to build a high loading electrode. A well-designed nano-structure was employed to achieve an areal capacity of ~3 mAh/cm 2 at a C/20 rate.…”

High Capacity and High Density Functional Conductive Polymer and SiO Anode for High-Energy Lithium-Ion Batteries

“…8,9 Instead of merely emphasizing the high specific capacities of Si-containing anode, recent focus in this field is on the fabrication of a thick and high-loading Si-containing electrode with high energy densities. 10 The drastic volume change of pure Si anode poses formidable challenges to build a thick electrode. Also, a high concentration of binder and conductive additive are typically required to achieve a satisfactory cycling performance, these inactive species (binder and carbon black) decrease the electrode level energy density to the extent that makes it less competitive than the state-of-the-art graphite electrode.…”

Modeling Volume Change in Dual Insertion Electrodes

“…electrode thickness) conditions. 18,[21][22][23][24][25][26][27][28][29][30][31][32][33][34][35] In many of these models, the dimensions of the porous electrode are often assumed constant and any volume changes in the active material result in only porosity changes. 21,22 Gomadam and Weidner 18 developed a model to allow both porosity and dimensional changes to occur.…”

“…24,[28][29][30][31] They reveal the importance that a change in volume plays in the generation of stresses and strains, and how this may be linked to experimentally observed failure in the active material. [32][33][34][35] The model developed here accounts for the stresses that build up in porous electrodes due to volume change in the active material through the application of porous rock mechanics to porous electrode theory. In previous models, a single electrode expanding against a casing with varying rigidity was examined 17,18 in order to derive analytical expressions that governed the volume change in a single electrode.…”