| In recent years,due to lithium ion batteries are reaching the limitation regarding their theoretical specific capacity,they cannot meet the needs of the rapidly developing emerging industries,nor can they meet the pursuit of battery life for portable electronic devices and pure electric vehicles.The development of next-generation high-energy density storage devices has become a top priority for energy researchers.With the research and development of new materials and the maturity of research technology in the field of batteries,rechargeable lithium metal batteries,which have been stagnation due to serious safety accidents,have returned to researchers’eyes.The bottlenecks of lithium metal anode are no longer impossible to overcome.In recent years,researchers have carried out a lot of work to explore a variety of effective coping strategies,among which the structure engineering of lithium anode is one of the most promising strategies.Herein,commercial carbon cloth was chosen as the base of the three-dimensional conductive host,aiming to design a 3D lithium metal anode host.Through surface modification of 3D carbon cloth,we can promote uniform nucleation and subsequent deposition of lithium,avoiding the growth of lithium dendrites Meanwhile,the volume of the electrode is kept constant during the cycle.Thus,the electrochemical performance of lithium anode such as cycle stability and cycle life are improved.A flexible CC@CN-Co lithium metal anode electrode host that inhibits Li dendrite growth and infinite relative volume change was successfully prepared by facile room-temperature crystallization route and subsequent heat treatment.Under the synergistic effect of uniformly distributed N-containing functional groups,tiny Co nanoparticles,and high active surface area,Li metal can be deposited uniformly on the surface of the carbon cloth fiber,and the thickness of the CC@CN-Co host does not change significantly.The symmetrical battery assembled with the composite Li metal anode can circulate stably for more than 1000 h at 5 m A cm-2 for a certain cyclic areal capacity of 5 m A h cm-2.CC@CN-Co//Li half-cells also exhibites better CE,which can be maintained at～98.3%after more than 100 cycles.In addition,the CC@CN-Co@Li//LFP@C full cells also shows excellent CE and capacity retention in the full-cell performance test,and delivers stable cycling for nearly 300 cycles with a CE of 98.7%.at 5C.Compared with the electroplating of Li,the molten Li infusion method is more conducive to practical application,avoiding contact of Li metal with the electrolyte which causes the formation of irreversible SEI components,can obtain a homogeneous and pyknotic Li deposition,and guarantees an extremely high energy density.A lipophilic host material CC@Zn O that can siphon molten Li was prepared by a facile room-temperature solution deposition method and heat treatment.The Zn O array improves the lipophilicity of the carbon cloth and has a strong adsorption effect on molten Li.CC@Zn O@Li composite Li metal anode assembled symmetrical cells can maintain a stable cycle of more than 1000 h（1000 cycles）with a～15 m V overpotential at 2 m A cm-2 for 1 m A h cm-2.At a higher current density of 10 m A cm-2,it can still be cycled more than 900 times stably,indicating that the above Li metal anode has a smooth and stable charge/discharge voltage platform.The CC@Zn O//Li half-cells also exhibited excellent coulombic efficiency with～99.7%over 500 cycles. |
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