非对称的三化芳香盐诱导化丰富接口,用于稳定循环的全固态电池
Shuaishuai Yan1, Fengxiang Liu1, Yu Ou1
1State Key Laboratory of Chemical Engineering, Department of Chemical Engineering, Tsinghua University, Beijing 100084, People's Republic of China.
ACS nano
|October 2, 2023
概括
新的盐通过改善离子运输和接口稳定性来增强固体聚合物电解质,使其更安全,更高性能的全固态金属电池. 这导致了更长的使用寿命和更好的电化学性能.
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
- 聚合物科学 聚合物科学
背景情况:
- 固体聚合物电解质 (SPEs) 对于安全,高能量密度的全固态金属电池至关重要.
- 传统的SPEs由于低离子转移数和不稳定的电极接口而受到影响,限制了电池的寿命.
- 开发先进的盐是克服这些局限性的关键.
研究的目的:
- 合成和评估用于聚合物电解质的新型不对称的三化芳香盐.
- 研究这些新盐对离子转移数和电解质/电极接口稳定性的影响.
- 为了证明全固态金属电池的性能提升.
主要方法:
- 合成 (3,4,5-trifluorobenzenesulfonyl) ((trifluoromethanesulfonyl) 胺基 (LiFFF) 和 (4--3,5-difluorobenzenesulfonyl) ((trifluoromethanesulfonyl) 胺基 (LiFBF) 的合成. 在这种过程中,的含量可以从中得到.
- 电解质性质的表征,包括离子转移数 (t+).
- 组装和测试Li/Li对称电池和LiFePO4/Li全电池,以评估接口稳定性和电化学性能.
主要成果:
- 与LiTFSI相比,LiFFF和LiFBF的t+值更高,与金属的兼容性更好.
- 三化芳离子促进LiF和LiBr丰富的固体电解质界面 (SEI) 的形成,增强界面稳定性.
- 基于LiFBF的电解质与LiF和LiBr形成混合SEI,优化离子流和扩散,导致稳定的循环 (>1200小时对称细胞,>1200循环全细胞).
结论:
- 不对称的三化芳盐为高性能SPEs提供了一个有前途的分子设计策略.
- 定制的SEI形成对于在固态电池中实现稳定的金属阳极接口至关重要.
- 这项研究为开发下一代固态金属电池提供了宝贵的见解,这些电池具有更高的安全性和寿命.
相关概念视频
01:19Acid Halides to Alcohols: LiAlH4 Reduction
2.9K
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...
2.9K
01:14Acid Halides to Ketones: Gilman Reagent
2.9K
Lithium dialkyl cuprate, also known as Gilman reagents, selectively reduces acid halides to ketones. The acid chloride is treated with Gilman reagent at −78 °C in the presence of ether solution to produce a ketone in good yield.
As shown below, the mechanism proceeds in two steps. First, one of the alkyl groups of the reagent acts as a nucleophile and attacks the acyl carbon of the acid chloride to form a tetrahedral intermediate. This is followed by the reformation of the carbon–oxygen...
As shown below, the mechanism proceeds in two steps. First, one of the alkyl groups of the reagent acts as a nucleophile and attacks the acyl carbon of the acid chloride to form a tetrahedral intermediate. This is followed by the reformation of the carbon–oxygen...
2.9K
02:48Ionic Bonding and Electron Transfer
41.7K
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.
41.7K
01:20Amides to Amines: LiAlH4 Reduction
4.9K
Amide reduction with strong reducing agents like lithium aluminum hydride proceeds through a nucleophilic acyl substitution to form amines. Primary, secondary, and tertiary amides yield primary, secondary, and tertiary amines, respectively.
Amide reduction requires two equivalents of the reducing agent, acting as a source of hydride ions. As shown in the figure, the reaction is initiated with a nucleophilic attack by the hydride ion at the carbonyl carbon to form a tetrahedral intermediate.
Amide reduction requires two equivalents of the reducing agent, acting as a source of hydride ions. As shown in the figure, the reaction is initiated with a nucleophilic attack by the hydride ion at the carbonyl carbon to form a tetrahedral intermediate.
4.9K
02:46Halogenation of Alkenes
15.8K
Halogenation is the addition of chlorine or bromine across the double bond in an alkene to yield a vicinal dihalide. The reaction occurs in the presence of inert and non-nucleophilic solvents, such as methylene chloride, chloroform, or carbon tetrachloride.
Consider the bromination of cyclopentene. Molecular bromine is polarized in the proximity of the π electrons of cyclopentene. An electrophilic bromine atom adds across the double bond, forming a cyclic bromonium ion intermediate.
Consider the bromination of cyclopentene. Molecular bromine is polarized in the proximity of the π electrons of cyclopentene. An electrophilic bromine atom adds across the double bond, forming a cyclic bromonium ion intermediate.
15.8K