电解质的可逆变化及其与电池中的LiO2中间体的相互作用的直接证据2
Bianca P Sousa1, Tuanan C Lourenço2, Chayene G Anchieta3
1Advanced Energy Storage Division Center for Innovation on New Energies (CINE)Laboratory of Advanced Batteries, School of Chemical Engineering, University of Campinas, Campinas, 13083-852, Brazil.
Small (Weinheim an der Bergstrasse, Germany)
|April 12, 2024
概括
使用二甲基硫氧化电解质的氧电池显示可逆反应和过氧化物形成. 本研究阐明了这些有前途的高能储能系统中的放电-充电机制.
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
- 化学工程是化学工程的重要组成部分.
背景情况:
- 氧 (Li-O2) 电池具有较高的理论能量密度,对于先进的能量存储至关重要.
- 了解复杂的反应机制和中间物种对于优化Li-O2电池性能至关重要.
研究的目的:
- 研究Li-O2电池与二甲基硫氧化物 (DMSO) 电解质和碳阴极的反应机制.
- 阐明中介物种在放电和充电周期中的作用.
主要方法:
- 运用拉曼光谱来监测现场化学变化.
- 开始密度函数理论 (DFT) 计算用于理论分析.
- 分子动力学 (MD) 模拟用于研究电解质-碳相互作用.
主要成果:
- 操作员拉曼证实了可逆的DMSO波段变化和Li2O2形成/分解.
- 在放电过程中存在DMSO-Li+相互作用的证据,得到DFT计算的支持.
- 模拟MD和Raman显示DMSO对LiO2 ((sol) 中间体的稳定性.
结论:
- 这项研究提供了关于使用DMSO电解质的Li-O2细胞的放电-充电化学的见解.
- 运行光谱学和理论方法的结合为Li-O2系统提供了必不可少的机械信息.
- 这项研究有助于开发更高效,更稳定的Li-O2电池技术.
相关概念视频
Electrolysis
26.3K
In a galvanic cell, the electrical work is done by a redox system on its surroundings as electrons produced by the spontaneous redox reactions are transferred through an external circuit. Alternatively, an external circuit does work on a redox system by imposing a voltage sufficient to drive an otherwise nonspontaneous reaction in a process known as electrolysis. For instance, recharging a battery involves the use of an external power source to drive the spontaneous (discharge) cell reaction in...
26.3K
Ladder Diagrams: Redox Equilibria
457
Ladder diagrams are useful tools for understanding redox equilibrium reactions, especially the effects of concentration changes on the electrochemical potential of the reaction. The vertical axis in the redox ladder diagrams represents the electrochemical potential, E. The area of predominance is demarcated using the Nernst equation.
Consider the Fe3+/Fe2+ half-reaction, which has a standard-state potential of +0.771 V. At potentials more positive than +0.771 V, Fe3+ predominates, whereas Fe2+...
Consider the Fe3+/Fe2+ half-reaction, which has a standard-state potential of +0.771 V. At potentials more positive than +0.771 V, Fe3+ predominates, whereas Fe2+...
457
Ionic Bonds
118.3K
Overview
When atoms gain or lose electrons to achieve a more stable electron configuration they form ions. Ionic bonds are electrostatic attractions between ions with opposite charges. Ionic compounds are rigid and brittle when solid and may dissociate into their constituent ions in water. Covalent compounds, by contrast, remain intact unless a chemical reaction breaks them.
Opposing Charges Hold Ions Together in Ionic Compounds
Ionic bonds are reversible electrostatic interactions between ions...
When atoms gain or lose electrons to achieve a more stable electron configuration they form ions. Ionic bonds are electrostatic attractions between ions with opposite charges. Ionic compounds are rigid and brittle when solid and may dissociate into their constituent ions in water. Covalent compounds, by contrast, remain intact unless a chemical reaction breaks them.
Opposing Charges Hold Ions Together in Ionic Compounds
Ionic bonds are reversible electrostatic interactions between ions...
118.3K
Batteries and Fuel Cells
27.3K
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...
27.3K
Balancing Redox Equations
52.1K
Electrochemistry is the science involved in the interconversion of electrical and chemical reactions. Such reactions are called reduction-oxidation, or redox reactions. These important reactions are defined by changes in oxidation states for one or more reactant elements and include a subset of reactions involving the transfer of electrons between reactant species. Electrochemistry as a field has evolved to yield sufficient insights on the fundamental principles of redox chemistry and multiple...
52.1K
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


