potential (−3.040 V vs standard hydrogen electrode). [8][9][10] Objectively, the energy density of Li batteries should take all parts of a battery into considerations instead of only anode. In order to achieve high-energydensity Li batteries, practical conditions including limited Li (<10 mAh cm −2 ), low negative/positive capacity (N/P) ratio (<3), and lean electrolyte are necessary. [11,12] In addition, fast charge is imperative with the popularization of portable electronics and electrical vehicles. [13] Consequently, high charge current density (>3 mA cm −2 ) is a confronted issue.Nowadays, the practical applications of Li batteries are still hindered by the formation of Li dendrites, rapid pulverizations of Li metal, and volume fluctuation. [14][15][16] Tremendous efforts have been devoted to disclosing the mechanism of Li plating/stripping and developing strategies to regulate its behaviors thus extending the lifespan of Li batteries during the past half century, including electrolyte formulations, [17][18][19][20][21][22][23][24][25][26][27] interfacial modifications, [28][29][30][31][32][33][34][35][36][37][38][39][40][41][42][43][44] solid-state electrolytes, [45][46][47][48][49][50][51][52][53][54][55] composite anodes, [56][57][58][59][60][61][62][63] and so on. [64] Thereinto, composite Li anode emerges as a promising strategy to regulate Li plating/stripping behaviors and promote the advances of Li batteries.Generally, a composite Li anode is composed of a 3D host and fresh Li metal. The 3D host is endowed with the unique surface chemistry and interconnecting structure. [65] The superiorities contributed by composite Li anode mainly include:(1) improving electronic conductivity, such as decreasing areal current density and avoiding the generation of "dead Li." Conductive hosts with high specific surface area, such as carbon-based and metal-based hosts, can decrease areal current density to prolong the time for depletion of ion at the anode surface to induce dendritic Li according to Sand's time model. [66] Therefore, the formation of Li dendrites will be effectively inhibited at low areal current density and the cyclability can be improved effectively.(2) Homogenizing Li-ion flux over the surface of Li metal. The distribution of Li ions over the surface of Li anode impacts the subsequent Li plating/stripping behaviors significantly. Uniform Li plating/ stripping can be improved by regulating the interactions between lithiophilic sites on 3D host surface, such as polar functional groups, [67,68] and Li ion to homogenize Li-ion flux. [69] (3) Maintaining dimensional stability of anode. 3D hosts can confine plating Li in the inside pores to avoid the Lithium (Li) metal is considered as a promising anode candidate for nextgeneration batteries owing to its extremely high specific capacity and low reduction potential. However, Li metal anode is still hindered by uncontrolled Li dendrites and extreme volume fluctuation. Composite Li metal anode emerges as an attractive strategy to suppress Li dendrites and ...

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We provide a chemical precipitation method to improve the thermoelectric properties of SnS. The largest ZT value is 0.41 at 848 K parallel to the pressing direction, which is much higher than that of mechanically-alloyed SnS materials.