Targeted Deposition in a Lithiophilic Silver-Modified 3D Cu Host for Lithium-Metal Anodes

Lithium-metal batteries are regarded as the"Holy Grail"of next-generation batteries.However,lithium dendrite and anode volume expansion in cycles seriously hinders lithium-metal battery applications.Herein,we propose a precise and efficient strategy for stabilizing lithium-metal batteries via a lithiophilic Ag-modified Cu current host(Li@CuM/Ag).By applying the magnetron sputtering method,the lithiophilic silver layer can be anchored homogeneously on the Cu mesh.The lithiophilic silver layer effectively guides uniform Li deposition in the 3D host and realizes spatial control over Li nucleation.In addition,a dendrite-free lithium anode is successfully realized,which has been proven by in situ optical dynamic tests and Li deposition simulations.The symmetrical cell can maintain a low overpotential(230 mV)and long cycle life(90 h)at a large current of 10 mA cm^(-2)for a plating amount of 3 mAh cm^(-2).Furthermore,Li@CuM/Ag||LiCoO2 cells exhibited a high-capacity retention rate(86.39%)after 150 cycles at 2 C.Lithiophilic hosts based on magnetron sputtering provide a feasible strategy for applications of lithium-metal batteries.

Facile and scalable fabrication of lithiophilic Cu_(x)O enables stable lithium metal anode

Equipped with highest-energy density anode,lithium metal batteries are of great interests for the nextgeneration energy storage systems.However,the existing problems like uneven Li deposition,large volume expansion and short cycling lifespan severely retard the implementation of Li metal anodes.Herein,we report an in-situ formed Cu_(x)O nanofiber network synthesized by facile and scalable calcination process and employ as stable lithium metal anode.The CuO/Cu_(2)O ratio in the lithiophilic Cu_(x)O network can be adjusted through an optimal annealing time,thus guiding the homogeneous distribution of Li atoms and regulating the repeated plating/stripping processes.As a result,Li@Cu_(x)O 3D scaffold displays an ultralow overpotential of 7.7 mV,long cycling life for more than 1000 h in symmetric cell,and exceptional stability for LiFePO_(4)//Li full cells.This work provides guidelines for the design and fabrication of lithiophilic 3D matrixes and advances the practical use of lithium metal batteries.

Guided lithium nucleation and growth on lithiophilic tin-decorated copper substrate

Lithium metal is the ultimate anode choice for high energy rechargeable lithium batteries owing to its ultra-high theoretical capacity,however,Li dendrites and low Coulombic efficiency(CE)caused by disordered Li plating restrict its practical application.Herein,we develop an ultrathin Sn-decorated Cu substrate(Sn@Cu)fabricated by an electroless plating method to induce ordered Li nucleation and growth behavior.The lithiophilic Sn interfacial layer is found to play a critical role to lower the Li nucleation over-potential and promote fast Li-migration kinetics,and the underlying mechanism is revealed using the first principle calculations.Accordingly,a dense dendrite-free and Li deposition with large granular morphology is obtained,which significantly improved the CE and cycling performance of Li‖Sn@Cu half cells symmetric cells.Symmetric cells using the Li-Sn@Cu electrode display a much-prolonged life span(>1200 h)with low overpotential(~18 mV)at a high current density of 1 mA cm^(-2).Moreover,full cells paired with commercial LiFePO_(4) cathode(1.8 mAh cm^(-2))deliver enhanced cycling stability(0.5 C,300 cycles)and excellent rate performance.This work provides a simple and effective way to bring about high efficiency and long lifespan substrates for practical applications.

A ZnO decorated 3D copper foam as a lithiophilic host to construct composite lithium metal anodes for Li-O_(2) batteries

Lithium metal batteries(LMBs) with a high theoretical capacity are seen as a type of the most potential energy storage system.Unfortunately,the growth of lithium dendrite,the irreversible side reactions,and the infinite volume alteration still curb the practical utilization of lithium metal anodes,resulting in low Coulombic efficiency(CE) and safety problems,etc.Herein,we synthesize a lithiophilic 3D copper foam host with uniformly distributed nano-flower-like ZnO particles(CuF/ZnO) and obtain the composite lithium metal anode containing the Li_(2)O,LiZn alloy,and pure Li by the infusion of molten Li(CuF/Li_(2)O-LiZn@Li).Benefitting from the advantages of the 3D structure of copper foam and the lithiophilicity of ZnO sites,the composite lithium metal anode can restrain the volume alternation and regulate the uniform deposition of lithium.The symmetrical cells of the composite lithium metal anode have a 1600 h long cycle life with a low polarization voltage of 15 mV,and the Coulombic efficiency can maintain about 97.8% at 1.0 mA·cm^(-2),1.0mAh·cm^(-2).

Present and future of functionalized Cu current collectors for stabilizing lithium metal anodes

Li metal has been recognized as the most promising anode materials for next-generation high-energy-density batteries,however,the inherent issues of dendrite growth and huge volume fluctuations upon Li plating/stripping normally result in fast capacity fading and safety concerns.Functionalized Cu current collectors have so far exhibited significant regulatory effects on stabilizing Li metal anodes(LMAs),and hold a great practical potential owing to their easy fabrication,low-cost and good compatibility with the existing battery technology.In this review,a comprehensive overview of Cu-based current collectors,including planar modified Cu foil,3D architectured Cu foil and nanostructured 3D Cu substrates,for Li metal batteries is provided.Particularly,the design principles and strategies of functionalized Cu current collectors associated with their functionalities in optimizing Li plating/stripping behaviors are discussed.Finally,the critical issues where there is incomplete understanding and the future research directions of Cu current collectors in practical LMAs are also prospected.This review may shed light on the critical understanding of current collector engineering for high-energy-density Li metal batteries.