Lithium Metal Anodes with Nonaqueous Electrolytes

Abstract

High-energy rechargeable lithium (Li) metal batteries (LMBs) with Li metal anode (LMA) were first developed in the 1970s, but their practical applications have been hindered by the safety and low-efficiency concerns related to LMA. Recently, a worldwide effort on LMA-based rechargeable LMBs has been revived to replace graphite-based, Li-ion batteries because of the much higher energy density that can be achieved with LMBs. This review focuses on the recent progress on the stabilization of LMA with nonaqueous electrolytes and reveals the fundamental mechanisms behind this improved stability. Various strategies that can enhance the stability of LMA in practical conditions and perspectives on the future development of LMA are also discussed. These strategies include the use of novel electrolytes such as superconcentrated electrolytes, localized high-concentration electrolytes, and highly fluorinated electrolytes, surface coatings that can form a solid electrolyte interphase with a high interfacial energy and self-healing capabilities, development of "anode-free" Li batteries to minimize the interaction between LMA and electrolyte, approaches to enable operation of LMA in practical conditions, etc. Combination of these strategies ultimately will lead us closer to the large-scale application of LMBs which often is called the "Holy Grail" of energy storage systems.

A “shuttle-relay” lithium metal battery enabled by heteroatom-based gel polymer electrolyte

“…4b and Supplementary Fig. [15][16][17][18]. The robust SEI can e ciently suppresses the formation of Li dendrite and dead Li (Fig.…”

“…As shown in the inset of Fig. 3a, the Li|Li symmetric cell using 1 M LiPF 6 -EC: EMC electrolyte exhibited a dramatically increased overpotential with cycling time (≈5 V at 420 h), mainly due to the thickening of SEI layer and continuous Li dendrite growth 18 . The overpotential of Li|1 M LiPF 6 -FEC: FEMC|Li cells and Li|1 M LiPFF 6 -FEC: FEMC: HTE|Li cells were ≈120 mV and ≈150 mV, and the cells failed at 600 h and 800 h, respectively (Supplementary Fig.…”

“…Fig. 1a illustrates the working mechanism of the quasi- 18 . On the cathode side, the insu cient oxidation resistance of carbonate solvents triggers severe electrolyte decomposition and constructs a thick CEI with high-resistance, which dramatically degrades the battery performance (Fig.…”

“…Meanwhile, the proportion of LiF, mainly originating from the reduction of uorinated solvents, greatly increased in the SEI (Supplementary Fig. [15][16][17][18]. It is well-known that LiF with high mechanical strength (i. e. a shear modulus of 55.1 GPa, almost 11 times higher than that of Li metal (4.9 GPa)) can signi cantly enhance the robustness and interfacial energy of SEI layers, thus blocking Li dendrite growth 24 .…”

Lithium‐Metal Anodes Working at 60 mA cm−2 and 60 mAh cm−2 through Nanoscale Lithium‐Ion Adsorbing

“…1000 h) at limited current densities ( 10 mA cm À2 ). [21] Hence, it is significant while challenging to efficiently regulate Li + concentration at the electrolyte-anode interface for practical Limetal anodes.…”