Gradient porosity electrodes for fast charging lithium-ion batteries

Abstract

The tendency of Li plating at the surface of thick graphite electrodes greatly limits its application in electrical vehicle (EV) batteries for fast charging applications. To address this concern, we...

Stable Zn Anodes with Triple Gradients

“…[31] Recently, electrodes with various gradient designs have shown advantages in optimizing the local charge-transport dynamics, thus achieving high energy and high-power energy storage devices. [32][33][34][35][36][37][38][39][40][41] For example, electrodes with gradient porosity have also been demonstrated to be effective in promoting ion transport and influencing deposition behavior, thus achieving enhanced cycling stability. [38] A dual-gradient graphite electrode that combines gradient porosity and gradient particle size illustrated a much-enhanced rate capability than the electrodes with single or no gradient design.…”

Mechanics-based design of lithium-ion batteries: a perspective

“…147–150 Meanwhile, owing to the complicated deformation state of active layers, the porosity and tortuosity may also exhibit anisotropic characteristics, which can further affect the electrochemical performance. By considering these mechanisms, the mesostructure of active layers can be designed, such as gradient designs 151–154 and hollow designs. 155–157…”

“…[147][148][149][150] Meanwhile, owing to the complicated deformation state of active layers, the porosity and tortuosity may also exhibit anisotropic characteristics, which can further affect the electrochemical performance. By considering these mechanisms, the mesostructure of active layers can be designed, such as gradient designs [151][152][153][154] and hollow designs. [155][156][157] Moreover, due to the commonly high stiffness of the solidstate electrolyte, 158,159 internal stresses caused by swelling/ contraction of active materials upon charge and discharge in solid-state batteries are much higher than those in conventional batteries.…”

N4-Vacancy-Functionalized Carbon for High-Rate Li-Ion Storage

“…The most crucial electrochemical energy storage technology for electric vehicles, portable electronics, and other high-energy-demanding devices is lithium (Li)-ion batteries. − However, their current graphite electrodes have poor specific energy and delayed Li + insertion kinetics, and, therefore, extensive research is being done to find novel electrode materials that will address these issues. − Silicon, − tin, phosphorus, , or transition-metal oxides promised high Li-storage capacity and energy, but their performance degraded greatly due to volume change during lithiation and delithiation, which led to dead active materials and a poor solid–electrolyte interface (SEI). − Synthetic carbon materials, designable from organic starting materials, unlike their crystalline counterparts, welcome large-extent heterodoping and pore management, which is of great benefit for obtaining large Li-storage capacity at high rates. , …”