Advanced Current Collector Materials for High-Performance Lithium Metal Anodes.

Lithium metal, as the "Holy Grail" of lithium battery anodes, is promising to be used in the next-generation of high-energy-density storage devices. However, serious safety risk and poor cycle performance are inevitable when bare lithium foil is used as the anode material, due to the uncontrolled growth of lithium dendrites, unstable solid electrolyte interface, and infinite volume expansion of lithium during cycling, which largely hinder the further commercial application of lithium metal batteries (LMBs). The utilization of up-to-date current collectors with specific composition and structure is believed to be effective to overcome these shortcomings. However, a systematic evaluation of the merit of different current collector materials for realizing high-performance lithium metal anodes is still lacking. This review summarizes the fashionable advanced current collector materials for long-life LMBs in recent years. The superiorities and related electrochemical performances by using these current collector materials are discussed in detail. It is expected that this review may promote the rational choice of appreciatory current collector materials with unique structure designs to extend the cycle life of lithium metal anodes for achieving the next-generation of high-energy-density LMBs.

RuO2 Particles Anchored on Brush-Like 3D Carbon Cloth Guide Homogenous Li/Na Nucleation Framework for Stable Li/Na Anode.

Lithium (sodium)-metal batteries are the most promising batteries for next-generation electrical energy storage due to their high volumetric energy density and gravimetric energy density. However, their applications have been prevented by uncontrollable dendrite growth and large volume expansion during the stripping/plating process. To address this issue, the key strategy is to realize uniform lithium (sodium) deposition during the stripping/plating process. Herein, a thin lithiophilic layer consisting of RuO2 particles anchored on brush-like 3D carbon cloth (RuO2 @CC) is prepared by a simple solution-based method. After infusion of Li, the RuO2 @CC transfers to Li-Ru@CC. Ru nanoparticles not only play a role in leading Li+ (Na+ ) to plate on the 3D carbon framework, but also lower local current density because of the good electrical conductivity. Furthermore, density functional theory calculations demonstrate that Ru metal, the reaction product of alkali metal and Ru, can lead Li+ to plate evenly around carbon fiber owing to the strong binding energy with Li+ . The Li-Ru@CC anode shows ultralong cycle life (1500 h at 5 mA cm-2 ). The full cell of Li-Ru@CC|LiFePO4 exhibits lower polarization (90% capacity retention after 650 cycles). In addition, sodium metal batteries based on Na-Ru@CC anodes can achieve similar improvement.

Dimensionally Stable Composite Li Electrode with Cu Skeleton and Lithophilic Li-Mg Alloy Microstructure.

Lithium electrodes have gained increasing attention in recent years for their promising applications in high-energy-density secondary batteries. However, structural instability during cycling remains a considerable obstacle to development. In this study, a dimensionally stable Li-Mg/Cu composite electrode was fabricated. Cu foam as a plate grid can sustain the structure, and Li-Mg alloy as the active and lithophilic component can guide the uniform Li plating within the composite. Thus, Li-Mg/Cu electrode shows long-term stability in terms of dimensional change and surface morphology. This work provides a facile and practical way to fabricate composite Li electrodes with high dimensional stability for secondary batteries.