Toward Critical Electrode/Electrolyte Interfaces in Rechargeable Batteries

Abstract

The electrode/electrolyte interface plays a critical role in stabilizing the cycling performance and prolonging the service life of rechargeable batteries to meet the sustainable energy requirements of the mobile society. The understanding of interfaces is still at the preliminary stage due to the limited research techniques and variable properties with time and potential. Herein, the latest developments focused on the interfaces in rechargeable systems including the cathode electrolyte interphase (CEI) and solid electrolyte interphase (SEI) are reviewed. The possible formation mechanisms of the electrode/electrolyte interface are discussed, followed by the introduction of two key influencing factors, specific adsorption and solvated coordinate structure, which will dominate the formation of the interface. Finally, the structure and chemical composition of the interface as well as the possible transport mechanism of lithium ions in the interface and the strategies to regulate the pathway through the interface are presented in detail. This work sheds light on the fundamental understanding of the interface and provides rational scientific principles in designing the electrode/electrolyte interface and inspires the rational design of long‐term cycling rechargeable batteries.

Regulating Interfacial Chemistry in Lithium‐Ion Batteries by a Weakly Solvating Electrolyte**

“…The Nobel Prize in Chemistry 2019 finally rewarded the development of Li-ion batteries (LIBs) as this light-weight, rechargeable, and ubiquitous energy storage device has profoundly revolutionized our modern life during the past 30 years. [1][2][3] The increasing demands of electric vehicles and grid energy storage is gradually pushing the performance of LIBs to their limits, including high energy density, fast charging, high safety, long life and low cost. [4][5][6][7][8] To meet these high bars, current LIBs must venture into more challenging territories such as Li/Si anodes, [9][10][11] high-voltage/capacity cathodes, [12][13][14] and aqueous LIBs.…”

A review on recent approaches for designing the SEI layer on sodium metal anodes

“…Since the lithium and sodium metal anodes possess a highly reductive nature, the electrolyte is spontaneously decomposed to form an organic/inorganic hybrid layer known as SEI layer on the alkali metal anodes as they are directly in contact with the electrolyte. 40 Because they belong to group 1 of the periodic table, the principle of formation and morphology, as well as elemental composition, are similar to some extent. The morphology and elemental composition of the formed layer have a crucial impact on the dendritic growth.…”

Challenges, mitigation strategies and perspectives in development of Li metal anode

“…[77,78] Electrolyte additives play a crucial role in the electrolyte system even though with a very low content. This is due to the fact that the chemical and physical properties of solid-state interphase layer are dominated by the electrolyte additives, [79,80] so electrolyte additive design has been widely investigated to tune SEI properties. These additives can decompose, polymerize or adsorb on the Li metal surface, thus modifying the interphase layer physicochemical properties and thereby rendering the lithium ion uniformly distribution during plating.…”