在微弱溶解电解质中调节离子双极相互作用,朝向超低温离子电池
Hengyi Fang1, Yaohui Huang1, Wei Hu1
1Frontiers Science Center for New Organic Matter, Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), State Key Laboratory of Advanced Chemical Power Sources, College of Chemistry, Nankai University, Tianjin, 300071, China.
Angewandte Chemie (International ed. in English)
|February 9, 2024
概括
一种新的弱溶解电解质 (WSE) 能够在超低温度下在硬碳阳极中稳定储存. 这一突破解决了离子电池 (SIB) 的容量衰减,通过改善离子溶解和固体电解质介相形成.
科学领域:
- 电化学 电化学 电化学
- 材料科学 材料科学 材料科学
- 储能 储能 储能 储能 储能 储能
背景情况:
- 离子电池 (SIB) 对储能具有前景,但在低温下面临容量衰减的挑战.
- 高Na+溶解能量和不稳定的固体电解质间相 (SEI) 阻碍了SIB在寒冷条件下的性能.
研究的目的:
- 设计一种弱溶解电解质 (WSE),用于在超低温度下在硬碳 (HC) 阳极中稳定地储存.
- 通过调节离子双极相互作用来改善Na+溶解动力学并促进稳定的SEI形成.
主要方法:
- 将2-甲基四二加入到四二中,以创建具有减少离子双极相互作用的WSE.
- 在不同温度下研究溶解结构和SEI形成.
- 在超低温度下测试HC阳极和HC光Na3V2(PO4) 3全电池的电化学性能.
主要成果:
- WSE的低点为-83.3°C,并增强了Na+溶解动力学.
- 在 -40°C (243.2 mAh g-1) 和 -60°C (205.4 mAh g-1) 的50 mA g-1下,HC阳极表现出高可逆容量.
- 完整的细胞在250个循环中实现了~100%的容量保留在-40°C.
结论:
- 具有调节的离子双极相互作用的弱溶解电解质对超低温SIBs有效.
- 设计的WSE有助于无机丰富的SEI形成,确保在极寒条件下稳定的性能.
- 这项研究为开发用于寒冷环境的高性能SIB提供了新的战略.
相关概念视频
Aqueous Solutions and Heats of Hydration
14.7K
Water and other polar molecules are attracted to ions. The electrostatic attraction between an ion and a molecule with a dipole is called an ion-dipole attraction. These attractions play an important role in the dissolution of ionic compounds in water.
When ionic compounds dissolve in water, the ions in the solid separate and disperse uniformly throughout the solution because water molecules surround and solvate the ions, reducing the strong electrostatic forces between them. This process...
When ionic compounds dissolve in water, the ions in the solid separate and disperse uniformly throughout the solution because water molecules surround and solvate the ions, reducing the strong electrostatic forces between them. This process...
14.7K
Electrolyte and Nonelectrolyte Solutions
63.0K
Substances that undergo either a physical or a chemical change in solution to yield ions that can conduct electricity are called electrolytes. If a substance yields ions in solution, that is, if the compound undergoes 100% dissociation, then the substance is a strong electrolyte. Complete dissociation is indicated by a single forward arrow. For example, water-soluble ionic compounds like sodium chloride dissociate into sodium cations and chloride anions in aqueous solution.
63.0K
Intermolecular Forces
58.3K
Atoms and molecules interact through bonds (or forces): intramolecular and intermolecular. The forces are electrostatic as they arise from interactions (attractive or repulsive) between charged species (permanent, partial, or temporary charges) and exist with varying strengths between ions, polar, nonpolar, and neutral molecules. The different types of intermolecular forces are ion–dipole, dipole–dipole, hydrogen bonds, and dispersion; among these, dipole–dipole, hydrogen...
58.3K
Ionic Strength: Effects on Chemical Equilibria
1.5K
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...
1.5K
Electrolytes: van't Hoff Factor
33.1K
Colligative Properties of Electrolytes
The colligative properties of a solution depend only on the number, not on the identity, of solute species dissolved. The concentration terms in the equations for various colligative properties (freezing point depression, boiling point elevation, osmotic pressure) pertain to all solute species present in the solution. Nonelectrolytes dissolve physically without dissociation or any other accompanying process. Each molecule that dissolves yields one...
The colligative properties of a solution depend only on the number, not on the identity, of solute species dissolved. The concentration terms in the equations for various colligative properties (freezing point depression, boiling point elevation, osmotic pressure) pertain to all solute species present in the solution. Nonelectrolytes dissolve physically without dissociation or any other accompanying process. Each molecule that dissolves yields one...
33.1K
Ionic Strength: Overview
1.4K
The ionic strength of a solution is a quantitative way of expressing the total electrolyte concentration of a solution. This concept was first introduced in 1921 by two American physical chemists, Gilbert N. Lewis and Merle Randall, while describing the activity coefficient of strong electrolytes. During the calculation of ionic strength (I or μ), all the cations and anions are considered. However, the concentration (c) of an ion with a greater charge number (z) has a greater contribution...
1.4K


