In‐plane Defect Engineering Enabling Ultra‐stable Graphene Paper‐based Hosts for Lithium Metal Anodes

Abstract

Graphene papers are widely studied as stable hosts to suppress lithium dendrite growth and accommodate the volumetric expansion for lithium metal anodes. Designing and constructing flexible graphene‐based films with unique structures as stable hosts in large scales for lithium metal anodes is challenging in terms of their realistic applications. Herein, scalable three‐dimensional (3D) holey reduced graphene oxide (HrGO) films with abundant as‐tailored oxygen functional groups on hole defects of graphene nanosheets are successfully constructed as stable hosts for lithium metal anodes. The as‐designed anodes deliver a stable voltage of 11 mV for 1900 h at a current density of 0.2 mA cm−2. The achieved cycling times of the optimized Li‐HrGO‐4 film anodes are over 1000 and 800 h at current densities of 0.5 and 1.0 mA cm−2, respectively. Simultaneously, the Li‐HrGO‐4 composite film anodes also exhibit superior rate performance as compared to pure lithium and Li‐rGO film anodes when utilized in symmetric cells. The as‐assembled LiFePO4/Li‐HrGO‐4 full cells show superior rate performance and retain capacity after 300 cycles at the rate of 1 C. Furthermore, first‐principles calculations indicate that C−O and O−C=O groups on defects of HrGO surfaces lead to excellent lithium affinity and uniform deposition. Above all, the unique 3D holey structure with as‐tailored oxygen defects and its design strategy holds a significant potential for the development of high energy‐dense and stable metal batteries.

High-flux charge transfer layer confers a solid electrolyte interphase with uniform and rich LiF for stable lithium metal batteries

“…2g and Table S1 †). [38][39][40][41][42][43][44][45][46][47][48][49] This conrmed that the GrGO/CNT-based HTCL strategy could greatly improve the charge transfer kinetics at the anode/ electrolyte interface.…”

Structural Design of 3D Current Collectors for Lithium Metal Anodes: A Review

“…Then, the porous rGO/Li contact with 11.7 mg molten Li (corresponding to a 15 mg cm −1 ) was used the anode, which was beneficial in migrating volume changes and suppressing Li dendrite formation. Conversely, Ma and coworkers [57] employed a defective etching reaction to possess the 3D layered holey rGO (HrGO) films with abundant as‐tailored oxygen functional groups on hole defects. The micropores of the rGO films improved electrolyte wettability and provided fast electron/ion pathway during charge/discharge process.…”

“…(g) Schematic illustration of the fabrication process for large-area 3D HGO films and Li-HrGO film anodes, and (h) galvanostatic cycling voltage profiles of symmetric cells are compared at current density of 1.0 mA cm À 2 . Reproduced from Ref [57]. Copyright (2021), with permission from Wiley.…”

A 3D Framework with Li3N–Li2S Solid Electrolyte Interphase and Fast Ion Transfer Channels for a Stabilized Lithium‐Metal Anode

“…Freestanding graphene oxide (GO) film has been proven to be an optimum lithium host because of its high flexibility, mechanical strength, and naturally lithiophilic property that can spontaneously absorb lithium and form a freestanding GO/Li electrode. Previous studies mainly concentrate on the structural and mechanical design for freestanding GO films, [35][36][37][38] while paying less attention to the inherent instability and fragility of the formed organic SEI. During high-rate and long-term cycling, these fragile SEI will easily crack and expose the fresh Li, repeatedly causing a large amount of lithium loss and dead lithium formation, which is reflected in a low CE.…”