Recent Advances in Solid-Electrolyte Interphase for Li Metal Anode

Abstract

Lithium metal batteries (LMBs) are considered to be a substitute for lithium-ion batteries (LIBs) and the next-generation battery with high energy density. However, the commercialization of LMBs is seriously impeded by the uncontrollable growth of dangerous lithium dendrites during long-term cycling. The generation and growth of lithium dendrites are mainly derived from the unstable solid–electrolyte interphase (SEI) layer on the metallic lithium anode. The SEI layer is a key by-product formed on the surface of the lithium metal anode during the electrochemical reactions and has been the barrier to development in this area. An ideal SEI layer should possess electrical insulating, superior mechanical modulus, high electrochemical stability, and excellent Li-ion conductivity, which could improve the structural stability of the electrode upon a long cycling time. This mini-review carefully summarizes the recent developments in the SEI layer for LMBs, and the relationship between SEI layer optimization and electrochemical property is discussed. In addition, further development direction of a stable SEI layer is proposed.

Ultrafine FeF3·0.33H2O Nanocrystal-Doped Graphene Aerogel Cathode Materials for Advanced Lithium-Ion Batteries

“…The emerging electrical vehicles (EVs) will gradually replace petrol vehicles and become the main means of transport in the near future due to their prominent advantages of energy saving and environmental protection. , Lithium-ion batteries (LIBs) hold the honor of being the “heart” of EVs, and their electrochemical performance determines the cruising range of EVs . Unfortunately, the energy density of LIBs is limited by the traditional intercalation-type cathode materials (such as LiFePO 4 , LiCoO 2 , LiMn 2 O 4 , LiNi x Mn y Co 1– x – y O 2 ), which can only provide an actual theoretical capacity of ∼200 mAh g –1 . − Additionally, the current commercial cobalt- and nickel-based cathode materials have low reserves and high prices, which seriously hinder their commercial application in LIBs.…”

Li Plating/Stripping Efficiency in Ether‐based Dilute Electrolyte for Anode‐free Lithium‐metal Batteries: Effect of Operating Potential Range on Subsequent SEI Layer Structure

“…A typical SEI layer consists of the reductive decomposition products of electrolyte but plays a role in suppressing further decomposition of electrolyte. [14,15] In AFLMBs with copper metal as the current collector, there is a "native-SEI (N-SEI)" layer forming right after cell assembly, which is composed of some Cu oxides and electrolyte decomposition products. [16] Moreover, an SEI layer forming after applying voltage but before the first Li plating and an SEI layer forming after the first Li stripping are defined as a "pre-SEI" layer and a "subsequent-SEI (s-SEI)" layer, respectively.…”

“…A typical SEI layer consists of the reductive decomposition products of electrolyte but plays a role in suppressing further decomposition of electrolyte [14,15] . In AFLMBs with copper metal as the current collector, there is a “native‐SEI (N‐SEI)” layer forming right after cell assembly, which is composed of some Cu oxides and electrolyte decomposition products [16] .…”

Coatings on Lithium Battery Separators: A Strategy to Inhibit Lithium Dendrites Growth

“…The SEI layer generated during the electrochemical cycling of the battery mainly prevents the reaction between the electrolyte and the electrode material. However, due to its high reactivity, lithium metal is extremely easy to react with the electrolyte, which leads to the continuous rupture and reconstruction of the SEI layer during cycling, increases the impedance of the battery, and reduces the cycling efficiency [29]. Conventional commercial lithium-ion batteries work by embedding and dragging lithium ions back and forth in the graphite anode during charging and discharging [30].…”