Seed-Free Selective Deposition of Lithium Metal into Tough Graphene Framework for Stable Lithium Metal Anode

Abstract

Graphene has been wildly used as a host to suppress dendrite growth to stabilize the lithium metal anode. However, the high overpotential of lithium deposition on pure graphene has to be lowered by doping or employing precious metals. Additionally, the soft nature of graphene rendered itself to aggregate, consequently squeezing room for lithium accommodation. Herein, a tough graphene framework composed of 3D periodic hollow spheres was reported as a free-standing host to stabilize lithium metal anodes. The prepared 3D periodic hollow structure not merely reinforces the framework to maintain hollow structure under pressure caused by assembling battery, but also lowers the overpotential without the help of dopant or precious metals. It is worthy to note that high efficiency of ion diffusion, thanks to the channels interconnecting hollow spheres by holes on the walls, benefits both suppression of lithium dendrite and rate capability. The properties of low density and high mechanical strength make graphene frameworks electrode a promising lightweight Li host material, which reveals a new avenue for designing high-energy density electrode materials.

Advances in the Design of 3D‐Structured Electrode Materials for Lithium‐Metal Anodes

“…[84] 3D-structured self-supported electrode materials can be also constructed from GNSs by a broad range of methods, and hence, several unique structures were suggested. [85][86][87][88] Li et al reported that heavy metal-based current collectors can be substituted with relatively lightweight GNS-based frameworks that have more lithiophilic sites and hierarchically porous structures and can be obtained by a Cu foam-assisted template method. [85] Pan et al used uniform polystyrene spheres to prepare 3D graphene frameworks comprising 3D periodic hollow spheres with interconnected 3D ion-diffusion channels by a template method (Figure 4g).…”

“…[85] Pan et al used uniform polystyrene spheres to prepare 3D graphene frameworks comprising 3D periodic hollow spheres with interconnected 3D ion-diffusion channels by a template method (Figure 4g). [86] As a hybrid carbon structure, a carbon nanofiberstabilized graphene aerogel film host was prepared from electrospun carbon nanofibers and graphene oxide using chemical reduction and a solution casting method. [87] In addition, vertically grown edge-rich GNSs were fabricated on SiO 2 nanowire@carbon nanofiber networks with a density of 0.012 g cm −3 by low-pressure CVD at 5 kPa.…”

“…Reproduced with permission. [ 86 ] Copyright 2019, American Chemical Society. h) Schematic illustration of reduced graphene oxide with a nanoscale interlayer.…”

“…3D‐structured self‐supported electrode materials can be also constructed from GNSs by a broad range of methods, and hence, several unique structures were suggested. [ 85–88 ] Li et al. reported that heavy metal‐based current collectors can be substituted with relatively lightweight GNS‐based frameworks that have more lithiophilic sites and hierarchically porous structures and can be obtained by a Cu foam‐assisted template method.…”

Highly elastic wrinkled structures for stable and low volume-expansion lithium-metal anodes

“…At the same capacity and different current densities, compared with other Li-metal batteries with 3D graphene current collectors, GCN exhibited advantages in terms of CE and cycling life (Fig. 4d and Table S2) [40][41][42][43][44][45][46][47][48][49][50][51]. At 5.0 mA cm −2 in ether electrolyte, the GCN electrode remained stable even after 100 cycles, while the rGO electrode exhibited fluctuating performance after 40 cycles.…”