Mitigating Metal Dendrite Formation in Lithium–Sulfur Batteries via Morphology-Tunable Graphene Oxide Interfaces

Abstract

Despite issues related to dendrite formation, research on Li metal anodes has resurged because of their high energy density. In this study, graphene oxide (GO) layers are decorated onto Li metal anodes through a simple process of drop-casting and spray-coating. The self-assembly of GO is exploited to synthesize coatings having compact, mesoporous, and macroporous morphologies. The abilities of the GO coatings to suppress dendrite formation are compared through Li|Li symmetrical cell charging at a current density of 5 mA cm −2 for 2000 cyclesa particularly abusive test. The macroporous structure possesses the lowest impedance, whereas the compact structure excels in terms of stability. Moreover, GO exhibits a low nucleation overpotential and is transformed into reduced GO with enhanced conductivity during the operation of the cells; both factors synergistically mitigate the issue of dendrite formation. Li−S batteries incorporating the GO-decorated Li anodes exhibit an initial capacity of 850 mA h g −1 and maintain their stability for 800 cycles at a C-rate of 1 C (1675 mA h g −1 ), suggesting the applicability of GO in future rechargeable batteries.

Mechanistic understanding of the role separators playing in advanced lithium‐sulfur batteries

“…Uniform electric field/ion flux achieved by the separator also contributes to uniform lithium electrodeposition. Thus, strenuous efforts have been made under the guidance of this purpose . Kim et al used a polydopamine (PD)‐modified separator to facilitate uniform Li + flux and enhance the separator‐lithium contraction to diminish lithium surface tension (Figure B) .…”

Comparative performance of ex situ artificial solid electrolyte interphases for Li metal batteries with liquid electrolytes

“…Carbonaceous materials employed as ASEIs include carbon paper, and graphene oxide (GO) and its derivatives ( Bai et al., 2018 ; Kim et al., 2018 ; Chen et al., 2019c ; Gao et al., 2019 ; Zhao et al., 2018 ). The vast use of GO and reduced GO (rGO) is motivated by their low cost, high specific surface area and electronic conductivity, and ability to facilitate Li + diffusion on surfaces and within interlayer gaps.…”

“…The morphology of GO and the presence of dopants can affect the ASEI performance. In particular, macroporous GO offered low tortuosity pathways for enhanced Li + diffusion ( Chen et al., 2019c ), while phosphorous functionalized rGO (PrGO) showed relatively low overpotential for Li nucleation, because of the strong interactions between P and Li ( Kim et al., 2018 ).…”

Recent Progress in High‐Performance Lithium Sulfur Batteries: The Emerging Strategies for Advanced Separators/Electrolytes Based on Nanomaterials and Corresponding Interfaces

“…[36] The other one is to alter the physical and chemical characteristics of the current collector surface in order to induce uniform nucleation and deposition of metallic lithium. Commonly conductive porous current collectors mainly involve graphene, [37] carbon nanotubes, [38] and porous carbon array [39] (Figure 3b), etc. Li et al achieved a guided growth of planar Li layers, instead of random Li dendrites, though self-assembled reduced graphene oxide.…”