Large‐Scale Modification of Commercial Copper Foil with Lithiophilic Metal Layer for Li Metal Battery

Abstract

and long cycle life are urgently pursued. [1][2][3][4] However, current lithium-ion batteries (LIBs) have almost reached their theoretical limitation. [5][6][7][8] So, developing novel electrode materials with high energy and power densities as well as long cycle life is of great significance. Li metal electrodes, hailed as "Holy Grail" electrode, show incomparable advantages including high specific capacity (3860 mAh g −1 ) and low electrochemical potential (−3.040 V vs standard hydrogen electrode) and have been considered as the most promising next-generation electrode materials for Li-S, Li-air batteries, and so on. [9][10][11] However, the lithium metal batteries (LMBs) always suffer dendritic Li during the repeated plating/stripping process, which not only causes the formation of lots of "dead Li" and blocks the Li + / electron transportation between the bulk Li and the electrolyte and furtherly results in the low coulombic efficiency (CE) but also is the main culprit in piercing the separator, giving rise to the internal short circuits and finally leading to the serious security risks. [12][13][14] In addition, the unstable solid electrolyte interphase (SEI) is formed repeatedly on the surface of Li metal during the charge-discharge process, which leads to the nonuniform Li ionic flux and further aggravates the growth of dendritic Li as well as depletes the electrolyte. [15][16][17][18] All these disadvantages lead to low CE and poor cyclability and further impede the commercialization of LMBs.In recent years, many attempts have been exerted to eliminate the formation of Li dendrite and enhance the cyclability of LMBs. Fabricating stable intrinsic SEI layer by the liquid electrolyte additives can improve partly the electrochemical performance. [19][20][21][22][23] Similarly, preparing artificial SEI layer with high Young's Modulus on the surface of the Li metal is another common way to suppress the dendrite growth. [24][25][26][27] Modified separator with functional materials for LMBs is also adopted to inhibit the formation of dendritic Li and shows some progress. [28] Solid electrolytes with high Young's modulus have exhibited good resistance to lithium dendrites in previous reports. [29,30] Although some good results are achieved by these strategies, the complicated synthesis process, high cost, great weight or instability during long-term cycle limit their practical applications. More recently, designing 3D collectors with a lithiophilic surface as host for storing Li metal, such as modified 3D Cu foam or Ni foam, shows some progress since large specific area of 3D structure is beneficial to decreasing the local current density and regulating the distribution of electric fieldThe application and development of lithium metal battery are severely restricted by the uncontrolled growth of lithium dendrite and poor cycle stability. Uniform lithium deposition is the core to solve these problems, but it is difficult to be achieved on commercial Cu collectors. In this work, a simple and commercially viable stra...

Electrochemical Characterization of Battery Materials in 2‐Electrode Half‐Cell Configuration: A Balancing Act Between Simplicity and Pitfalls

“…Anode‐free cell tests : For measurements in anode‐free cells, Cu foil (Gould Electronics, 18 μm) was pre‐treated by NaOH and H 2 SO 4 and modified by dip‐coating into a 1 mM solution of AgNO 3 (AppliChem GmbH, 99.8 %) in distilled water to create a lithiophilic layer [98] and used as working electrode. Two layers of glass fiber separator (Whatman GF/C) were soaked with overall 120 μl of 1 M LiPF 6 in EC:DMC (1 : 1 v/v) as electrolyte.…”

Confronting the Challenges in Lithium Anodes for Lithium Metal Batteries

“…Uniformly decorating hosts using lithiophilic materials with low overpotential for Li nucleation is a common strategy. [ 134 ] Some metals (Au, [ 135 ] Ag, [ 136 , 137 ] Zn, Sn [ 134 ] ), metallic oxides (TiO 2, [ 138 ] Co 3 O 4, [ 139 ] Cu 2 O, [ 140 ] ZnO [ 23 ] ), and other materials (carbon with defects [ 141 ] or heteroatom, [ 125 ] porphyrin [ 119 ] ) are decorated on 3D current collectors as lithiophilic sites. Li + is guided by these lithiophilic sites to deposit uniformly inside the host when batteries are charged.…”

Recent Advances of Emerging 2D MXene for Stable and Dendrite‐Free Metal Anodes

“…[66][67][68] Improving the Wetting Ability of Substrate: The wetting ability of substrate with alkali metal plays an important role in the following uniform deposition of alkali metal. [69][70][71] A good wetting ability is able to lower the initial nucleation barrier (nucleation overpotential) of alkali metal on the substrate, resulting in a dense and dendrite-free alkali-metal deposition. [72][73][74] The wetting ability of the substrate can be improved by using seeds, modifying the surface or introducing materials that can react with alkali metals.…”