球状化:前体形态对固态化过程对高质量超高氧化物阴极的前体形态的影响
Wenbiao Liang1,2, Yin Zhao2, Liyi Shi2,3
1School of Materials Science and Engineering, Shanghai University, Shanghai, 200444, China.
Angewandte Chemie (International ed. in English)
|June 7, 2024
概括
超高层氧化物阴极的球状化前体提高了循环稳定性. 球形前体防止刚性外形成,增强高能电池中的扩散和电化学性能.
科学领域:
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
- 固态化学 固态化学
背景情况:
- 具有超高含量的分层氧化物对高能量密度阴极有希望.
- 循环稳定性问题源于化过程中的异质结构转变.
- 在前体颗粒上形成密集的外阻碍了的扩散.
研究的目的:
- 研究LiNi0.92Co0.04Mn0.04O2.2.的固态化过程.
- 了解前体粒子形状在结构进化中的作用.
- 制定一种策略,通过前体形态控制来提高阴极性能.
主要方法:
- 深入研究LiNi0.92Co0.04Mn0.04O2.2.的固态化情况.
- 球形和非球形前体粒子的比较分析.
- 电化学性能测试,包括特定容量和周期保留.
主要成果:
- 当地过度的LiOH促进非球形前体的刚性外,阻碍了化.
- 球形前体导致统一的结构演变和改进的扩散.
- 来自球形前体的超高阴极表现出高的初始容量 (234.2 mAh g-1) 和优秀的保留率 (89.3%在200个循环后).
结论:
- 前体形状在固态化过程中显著影响结构变化.
- 前体的球化是一种可行的策略,可以增强超高阴极的电化学特性.
- 这项工作为优化先进的储能应用的阴极材料提供了洞察力.
相关概念视频
Protein Folding
Overview
Protein Denaturation
The function of proteins depends on their native three-dimensional structure, which is dictated by the amino acid sequence of the specific protein. Folding of the polypeptide chain takes place under specific conditions that energetically favor the folded conformation. In contrast, protein denaturation occurs spontaneously under unfavorable conditions that disrupt the integrity of the folded conformation. Thus, the chemical and physical environment of a protein, such as significant changes in pH...
Plastic Behavior
A material's elastic behavior is characterized by the disappearance of stress once the load is removed, allowing the material to return to its original state. However, when stress surpasses the yield point, yielding commences, marking the onset of plastic deformation or permanent set. This change from elastic to plastic behavior is influenced by the peak stress value and the duration before the load is removed. An intriguing observation occurs when a specimen is loaded, unloaded, and reloaded.
Plastic Deformations
It is essential to understand how structural members behave under plastic deformation when the bending stress exceeds the material's yield strength. This state of deformation permanently alters the shape of the member, in contrast to the linear elastic behavior observed before yielding. The strain at any point in the member is expressed in terms of maximum strain. Notably, the neutral axis, which coincides with the centroid during elastic bending, shifts away from the centroid under plastic...
Plastic Deformations
Plastic deformation represents a fundamental concept in materials science, which explains the irreversible change in the shape of a material when it experiences stress beyond its elastic capability. This phenomenon is important in structural engineering, especially in designing and analyzing cantilever beams—structures that are securely fixed at one end and bear loads at the opposite end. When these beams are subjected to loads within their elastic range, they will return to their original...
Transition Zone
The transition zone in concrete is a critical area where aggregate meets cement paste, marked by a distinct porosity and weakness compared to the surrounding material. The adhesion around the aggregates is primarily due to Van Der Waals forces. The voids within this zone influence its robustness; initially, it is less durable than the surrounding bulk mortar due to larger voids. Initially, when concrete is compacted, a higher water-cement ratio near the aggregates leads to the formation of...


