A lightweight carbon nanofiber-based 3D structured matrix with high nitrogen-doping level for lithium metal anodes

Abstract

Lithium metal is considered to be the most promising anode material for the next-generation rechargeable batteries. However, the uniform and dendrite-free deposition of Li metal anode is hard to achieve, hindering its practical applications. Herein, a lightweight, free-standing and nitrogen-doped carbon nanofiber-based 3D structured conductive matrix (NCNF), which is characterized by a robust and interconnected 3D network with high doping level of 9.5 at%, is prepared by electrospinning as the current collector for Li metal anode. Uniform Li nucleation with reduced polarization and dendrite-free Li deposition are achieved because the NCNF with high nitrogen-doping level and high conductivity provide abundant and homogenous metallic Li nucleation and deposition sites. Excellent cycling stability with high coulombic efficiency are realized. The Li plated NCNF was paired with LiFePO 4 to assemble the full battery, also showing high cyclic stability.

In Situ Growing Chromium Oxynitride Nanoparticles on Carbon Nanofibers to Stabilize Lithium Deposition for Lithium Metal Anodes

“…[ 37 ] In general, the nitrogen functional groups in the N‐doped carbon materials, especially N‐6 and N‐5, are lithiophilic, which could enhance Li + diffusion velocity and guide the uniform deposition of Li metal. [ 17,49,50 ] Interestingly, the pyridinic‐N in CrCFs and ACrCFs is 0.4 eV higher (398.7 eV) than that in ACFs and CFs (398.3 eV). This phenomenon may be caused by the partial electron transfer from the pyridinic‐N to the N of chromium nitride.…”

“…Nevertheless, most of the unmodified CNFs have a poor affinity with Li metal, which the lithiophilicity of these carbon materials needs to be improved to stabilize lithium deposition. On the one side, heteroatom doping CNFs, such as nitrogen‐doped CNFs [ 17 ] and oxygen enriched CNFs, [ 18,19 ] could lead to a uniform Li metal deposition on the 3D hosts. On the other side, the nanoparticle‐modified CNFs can also improve the cycle stability of lithium metal anodes.…”

Building Safe Lithium-Ion Batteries for Electric Vehicles: A Review

“…For example, the objective of energy density is set to be 350 Wh kg −1 for the cell and 250 Wh kg −1 for the pack by 2020, and the driving range of EVs is set to be 400 km for one charge in China [4]. Presently, in order to achieve the above energy density goals, many efforts have been focused on developing high-capacity cathode and anode materials of LIBs [5][6][7]. For cathode materials, Ni-rich ternary materials Li [8,9], while on the anode side, major efforts have been devoted to constructing siliconbased [10] or tin-based carbon composites with high capacity and good cycling stability [11].…”

Flexible, high-voltage, ion-conducting composite membranes with 3D aramid nanofiber frameworks for stable all-solid-state lithium metal batteries

“…The further utilization of Li metal anodes with high ca-pacity (3860 mA h g −1 ) and low reduction potential (−3.04 V vs. standard hydrogen electrode) offers a major way to obtain high-energy-density LIBs [3,4]. However, the Li dendrite formation/growth results in serious safety risks such as overheating and short circuit [5,6]. Additionally, the commonly used organic liquid electrolytes with high flammability, narrow electrochemical window and more side reactions aggravate the safety issues [7,8].…”