A bifunctional surfactant-like electrolyte additive for a stable lithium metal anode.

Nonafluorobutanesulfonyl fluoride (NtF) was developed as a bifunctional additive for enhancing the stability of the lithium metal anode. NtF can yield Nt+ and LiF. The presence of lithiophobic and lithiophilic groups in Nt+ facilitates the uniform deposition of Li+, while LiF contributes to forming a stable solid electrolyte interphase.

Fullerenol as a nano-molecular sieve additive enables stable zinc metal anodes.

Aqueous zinc batteries (AZBs) with the advantages of safety, low cost, and sustainability are promising candidates for large-scale energy storage devices. However, the issues of interface side reactions and dendrite growth at the zinc metal anode (ZMA) significantly harm the cycling lifespan of AZBs. In this study, we designed a nano-molecular sieve additive, fullerenol (C60(OH)n), which possesses a surface rich in hydroxyl groups that can be uniformly dispersed in the aqueous solution, and captures free water in the electrolyte, thereby suppressing the occurrence of interfacial corrosion. Besides, fullerenol can be further reduced to fullerene (C60) on the surface of ZMA, holding a unique self-smoothing effect that can inhibit the growth of dendritic Zn. With the synergistic action of these two effects, the fullerenol-contained electrolyte (FE) enables dendrite-free ZMAs. The Zn-Ti half-cell using FE exhibits stable cycling over 2500 times at 5 mA cm-2 with an average Coulombic efficiency as high as 99.8 %. Additionally, the Zn-NaV3O8 cell using this electrolyte displays a capacity retention rate of 100 % after 1000 cycles at -20 °C. This work provides important insights into the molecular design of multifunctional electrolyte additives.

Stable cyclic ether as an electrolyte additive for high-performance lithium metal batteries.

Introducing a methyl group into 1,3-dioxolane (DOL) to obtain a stable cyclic ether, 4-methyl-1,3-dioxolane (4-Me DOL), allows it to be used as an additive in LiPF6-based carbonate electrolytes. The addition of 4-Me DOL can form a stable SEI with good Li+ transport ability, which can simultaneously improve the rate capability and cycling performance of lithium metal batteries.

Reactivation of an air-passivated lithium metal anode through halogen regulation.

A comprehensive study was conducted to investigate the failure mechanism of the lithium metal anode (LMA) in air. Simultaneously, an effective reactivation strategy was developed using halogen regulation. Specifically, iodine treatment converts the passivation layer of the exposed Li into LiI with fast Li+ transport ability, thereby improving the electrochemical performance.