Lithium (Li) metal with high theoretical capacity and the lowest electrochemical potential has been proposed as the ideal anode for high-energy-density rechargeable battery systems. However, the practical commercialization of Li metal anodes is precluded by a short lifespan and safety problems caused by their intrinsically high reductivity, infinite volume change, and uncontrollable dendrite growth during deposition and dissolution processes. Plenty of strategies have been introduced to solve the above-mentioned problems. Among these, controlling Li + flux plays a vital role to directly influence the plating and stripping process. In this work, the fundamental effect of Li + flux distribution on Li nucleation and early dendrite growth is discussed. Then, recent strategies of controlling Li + flux to suppress dendrite formation and growth through materials design are summarized, including homogenizing Li + flux, localizing Li + flux, and guiding gradient Li + distribution. Finally, underexplored materials are proposed and explored to control Li + flux and further directions for dendrite-free Li anodes. It is expected that this progress report will help to deepen the understanding of Li + flow tuning and morphology control of Li anodes and eventually facilitate the practical application of Li metal batteries.

intercalation reaction mechanism of commercialized graphite anodes, the energy density of LIBs is nearly approaching its theoretical limits (350 Wh kg −1 ). [2,3] More advanced alternative electrodes are urgently needed to satisfy the growing demand for portable electronics and electric vehicles. [4] With the ultrahigh theoretical specific capacity (3860 mAh g −1 ) and lowest electrochemical potential (−3.040 V vs standard hydrogen electrode), lithium (Li) metal is considered as the most desirable anode for next-generation high energy-storage applications, [5][6][7] including rechargeable Li-S [8][9][10] and Li-O 2 batteries. [11,12] Nevertheless, challenges still remained and the following issues are still urgently needed to be settled: 1) the intrinsic high reactivity of Li metal accelerates the corrosive side reactions between Li and electrolyte, leading to low Coulombic efficiency and Li anode degradation. [1,13] 2) Infinite volume fluctuation of Li anodes brings serious damage to the fragile solid electrolyte interphase (SEI), and causes unstable Li anode/liquid electrolyte interface during Li plating/stripping. [5,14] 3) The uncontrollable Li dendrite growth impales the separator, resulting in catastrophic combustion and explosion. [15] To effectively address the aforementioned problems, numerous strategies have been proposed, including structured anode design, [16][17][18][19] in/ex-situ artificial SEI protective layer, [20,21] functional electrolyte additives, [22,23] and solid/quasisolid-state electrolytes. [24][25][26][27] Specifically, structured anode can manipulate the electric field redistribution on Li surface, decrease the local current density and accommodate large volume fluctuation during cycling, while the unwell protected large surface area would lead to more serious parasite reactions. Alternatively, the artificial protective layer and functional additives could enhance the plating quality by modifying the SEI composition, but the severe anode volume change and inevitable additive consumption always leads to failure in long cycling operation, especially under high current density. The solid/quasi-solid-state electrolyte is considered to be a relatively safe way to replace the traditional flammable liquid electrolyte. However, the high electrolyte/electrode interface resistance and low ionic conductivity at room temperature are still hard to be resolved. Therefore, though all these strategies have made great progress, further improvements are Lithium metal anodes are considered the most promising anode for nextgeneration high-energy-density batteries due to their high theoretical capacity and low electrochemical potential. However, intractable barriers, especially the notorious dendrite growth, severe volume expansion, and side reactions, have obstructed its large-scale application. Numerous strategies from different points of view are explored to surmount these obstacles. Within these efforts, dynamically engineering the forces applied during the electrochemical process plays a significant r...

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