稳定4.6V LiCoO2通过Er和Mg在Li-Site和Co-Site分别的微量注
Jing Xia1,2, Na Zhang3, Ding Yi4,5
1College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, P. R. China.
Small (Weinheim an der Bergstrasse, Germany)
|February 16, 2024
概括
这项研究稳定了氧化 (LiCoO2) 在高电压下使用新的Er和Mg共. 这种双重兴奋剂策略提高了先进电池应用的稳定性和能量密度.
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:
- 高压充电LiCoO2提供更高的容量,但受到相位过渡和容量退化的影响.
- 传统的兴奋剂方法主要集中在位上,在高压稳定方面取得的成功有限.
研究的目的:
- 开发一种新的策略,以4.6V稳定LiCoO2的电压.
- 研究 LiCoO2 结构中的特定位置与 (Mg) 和 (Erb) 联合兴奋剂的协同效应.
主要方法:
- 使用了理论计算和实验验证.
- 在Li-site和Mg在Co-site. LiCoO2被添加了Er. 在Li-site和Mg在Co-site.
- 用半细胞和全细胞配置来评估电化学性能.
主要成果:
- 在Co-site的Mg兴奋剂抑制了在4.2V周围的六边形-单临床过渡,但破坏了晶格氧的稳定.
- 在Li位点的Er兴奋剂增强了晶格氧气稳定性,减轻了4.45V以上的相位过渡.
- Er,Mg联合合的LiCoO2在半电池中在4.6V的500个循环中表现出了显著的稳定性.
结论:
- 和联合的协同效应有效地稳定了LiCoO2在高压下.
- Er,Mg联合合的LiCoO2在一个完整的电池中达到310.8Wh kg-1的高能量密度,在100个循环中保持91.3%的容量.
相关概念视频
Ionic Bonding and Electron Transfer
Ions are atoms or molecules bearing an electrical charge. A cation (a positive ion) forms when a neutral atom loses one or more electrons from its valence shell, and an anion (a negative ion) forms when a neutral atom gains one or more electrons in its valence shell. Compounds composed of ions are called ionic compounds (or salts), and their constituent ions are held together by ionic bonds: electrostatic forces of attraction between oppositely charged cations and anions.
Valence Bond Theory
Coordination compounds and complexes exhibit different colors, geometries, and magnetic behavior, depending on the metal atom/ion and ligands from which they are composed. In an attempt to explain the bonding and structure of coordination complexes, Linus Pauling proposed the valence bond theory, or VBT, using the concepts of hybridization and the overlapping of the atomic orbitals. According to VBT, the central metal atom or ion (Lewis acid) hybridizes to provide empty orbitals of suitable...
Crystal Field Theory - Octahedral Complexes
Crystal Field Theory
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
Acid Halides to Alcohols: LiAlH4 Reduction
Acid halides are reduced to alcohols in the presence of a strong reducing agent like lithium aluminum hydride.
The mechanism proceeds in three steps. First, the nucleophilic hydride ion attacks the carbonyl carbon of the acid halide to form a tetrahedral intermediate. Next, the carbonyl group is re-formed, and the halide ion departs as a leaving group, generating an aldehyde. A second nucleophilic attack by the hydride yields an alkoxide ion, which, upon protonation, gives a primary alcohol as...
The mechanism proceeds in three steps. First, the nucleophilic hydride ion attacks the carbonyl carbon of the acid halide to form a tetrahedral intermediate. Next, the carbonyl group is re-formed, and the halide ion departs as a leaving group, generating an aldehyde. A second nucleophilic attack by the hydride yields an alkoxide ion, which, upon protonation, gives a primary alcohol as...
Complexation Equilibria: Factors Influencing Stability of Complexes
In complexation reactions, metal cations are the electron pair acceptors, and the ligands are the electron pair donors. The stability of the metal complexes depends primarily on the complexing ability of the central metal ion and the nature of the ligands. Generally, the complexing ability of the metal ion depends on the size and charge of the ion. As the metal ion size increases, the stability of the metal complexes decreases, provided that the valency of the metal ion and the ligands remain...
Lattice Energies of Ionic Crystals
Lattice energy represents the energy released when gaseous cations and anions combine to form an ionic solid, reflecting the strength of electrostatic interactions within the crystal. This process is fundamentally governed by Coulombic attraction between oppositely charged ions, where the potential energy varies inversely with the interionic distance and directly with the product of ionic charges. As ions approach one another, the electrostatic energy becomes increasingly negative, indicating a...


