效应调节离子溶解使高压金属电池能够稳定循环
Yuelang Chen1,2, Zhiao Yu1,2, Paul Rudnicki1
1Department of Chemical Engineering, Stanford University, Stanford, California 94305, United States.
Journal of the American Chemical Society
|October 28, 2021
概括
研究人员通过设计一种新的电解质溶剂1,2-二氧乙 (DEE) 来提高金属电池的性能. 这种分子设计增强了接口稳定性,为高压应用提供更长的电池寿命.
科学领域:
- 材料科学
- 电化学
- 化学工程
背景情况:
- 1,2-二甲 (DME) 是金属电池的常见电解质溶剂,但在库伦比效率和高压稳定性方面面临挑战.
- 现有的基于DME的电解质在高压全电池中具有长期循环性的局限性.
研究的目的:
- 引入一个分子设计原理,使用硬质阻碍调整+离子溶解结构.
- 研究1,2-二氧乙 (DEE) 作为比DME更好的电解质溶剂的潜力.
- 在高压金属电池中提高阳极和阴极的界面稳定性.
主要方法:
- 通过在DME中用更大的乙氧基替换分子设计,以产生DEE.
- 使用硬质阻碍影响溶解结构并创建富含离子的内部溶解外.
- 对 LiFSI/DEE 电解质的电化学稳定性的实验和计算分析.
主要成果:
- 与DME相比,使用DEE的基于硬体效应的设计显示出更好的电化学稳定性.
- 在严格的全电池测试中 (4.8 mAh cm-2 NMC811,4.4 V切断),LiFSI/DEE电解质达到182个周期,容量保持80%.
- 在相同的条件下,LiFSI/DME电解质只能达到94个循环,这突显了DEE的优异性能.
结论:
- 基于以太的电解溶剂的分子设计,如DEE,为实用的高压金属电池提供了有前途的策略.
- 立体阻碍是调结构和增强界面稳定的有效原则.
- 开发的LiFSI/DEE电解质显示出对金属电池技术的重大潜力.
相关概念视频
Ionic Strength: Effects on Chemical Equilibria
2.0K
The addition of an inert ionic compound increases the solubility of a sparingly soluble salt. For example, adding potassium nitrate to a saturated solution of calcium sulfate significantly enhances the solubility of calcium sulfate. Le Châtelier's principle cannot predict this shift in the equilibrium. Instead, this could be explained in terms of changes in the effective concentration of the ions in solution in the presence of added inert salt.
In this solution, the primary...
In this solution, the primary...
2.0K
Solvating Effects
8.0K
An understanding of the solvating effect helps rationalize the relation between solvation and acidity of the compound. In addition, this also explains the relative stability of conjugate bases for compounds with different pKa values. This lesson details, in-depth, the principle of solvating effects. The strength of an acid and the stability of its corresponding conjugate base are determined using pKa values. This observed relationship is a consequence of solvation, which is the interaction...
8.0K
Complexation Equilibria: Factors Influencing Stability of Complexes
538
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...
538
Formation of Complex Ions
24.4K
A type of Lewis acid-base chemistry involves the formation of a complex ion (or a coordination complex) comprising a central atom, typically a transition metal cation, surrounded by ions or molecules called ligands. These ligands can be neutral molecules like H2O or NH3, or ions such as CN− or OH−. Often, the ligands act as Lewis bases, donating a pair of electrons to the central atom. These types of Lewis acid-base reactions are examples of a broad subdiscipline called coordination...
24.4K
Batteries and Fuel Cells
28.6K
A battery is a galvanic cell that is used as a source of electrical power for specific applications. Modern batteries exist in a multitude of forms to accommodate various applications, from tiny button batteries such as those that power wristwatches to the very large batteries used to supply backup energy to municipal power grids. Some batteries are designed for single-use applications and cannot be recharged (primary cells), while others are based on conveniently reversible cell reactions that...
28.6K
Leveling Effect
1.1K
In acid-base chemistry, the leveling effect refers to the limitation imposed by the solvent on the strength of acids and bases in solution. When a base stronger than the solvent's conjugate base is used, it deprotonates the solvent until the base is entirely consumed, making it ineffective against weaker acids. Conversely, an acid stronger than the solvent's conjugate acid protonates the solvent until the acid is depleted, rendering it ineffective against weaker bases. Essentially, the...
1.1K


