Ultrathin Lithiophilic 3D Arrayed Skeleton Enabling Spatial-Selection Deposition for Dendrite-Free Lithium Anodes

Lithium metal batteries are promising to become a new generation of energy storage batteries. However, the growth of Li dendrites and the volume expansion of the anode are serious constraints to their commercial implementation. Herein, a controllable strategy is proposed to construct an ultrathin 3D hierarchical host of honeycomb copper micromesh loaded with lithiophilic copper oxide nanowires (CMMC). The uniquely designed 3D hierarchical arrayed skeletons demonstrate a surface-preferred and spatial-selective effect to homogenize local current density and relieve the volume expansion, effectively suppressing the dendrite growth. Employing the constructed CMMC current collector in a half-cell, >400 cycles with 99% coulombic efficiency at 0.5 mA cm⁻² is performed. The symmetric battery cycles stably for >2000 h, and the full battery delivers a capacity of 166.6 mAh g⁻¹. This facile and controllable approach provides an effective strategy for constructing high-performance lithium metal batteries.     

Uniform Zinc Deposition Regulated by a Nitrogen-Doped MXene Artificial Solid Electrolyte Interlayer

The dendrite growth and side reactions of zinc metal anode in mildly acidic electrolytes seriously hinder the practical application of aqueous zinc–ion battery. To address these issues, an artificial protective layer of nitrogen-doped MXene (NMX) is used to protect the zinc anode. The NMX protective layer has high conductivity and uniformly distributed zincophilic sites, which can not only homogenize the local electric field on the electrode interface but also accelerate the kinetics for Zn deposition. As a result, the NMX protective layer induces uniform zinc deposition and reduces the overpotential of the electrode. Encouragingly, this NMX-protected Zn anode can cycle stably for 1900 h at 1 mA cm⁻² and 1 mAh cm⁻². In asymmetric cells, it achieves high cycle reversibility with an average Coulomb efficiency of 99.79% for 4800 cycles at 5 mA cm⁻².     

Heterostructured Interface Enables Uniform Zinc Deposition for High-Performance Zinc-Ion Batteries

Zinc metal has considerable potential as a high-energy anode material for aqueous batteries due to its high theoretical capacity and environmental friendliness. However, dendrite growth and parasitic reactions at the electrode/electrolyte interface remain two serious problems for the Zn metal anode. Here, the heterostructured interface of ZnO rod array and CuZn₅ layer is fabricated on the Zn substrate (ZnCu@Zn) to address these two issues. The zincophilic CuZn₅ layer with abundant nucleation sites ensures the initial uniform Zn nucleation process during cycling. Meanwhile, the ZnO rod array grown on the surface of the CuZn₅ layer can guide the subsequent homogeneous Zn deposition via spatial confinement and electrostatic attraction effects, leading to the dendrite-free Zn electrodeposition process. Consequently, the derived ZnCu@Zn anode exhibits an ultra-long lifespan of up to 2500 h with symmetric cells at the current density and capacity of 0.5 mA cm⁻²/0.5 mA h cm⁻². Besides, a remarkable cyclability (75% retention for 2500 cycles at 2 A g⁻¹) is achieved in the ZnCu@Zn||MnO₂ full cell with a capacity of 139.7 mA h g⁻¹. This heterostructured interface with specific functional layers provides a feasible strategy for the design of high-performance metal anodes.     

Novel Organophosphate-Derived Dual-Layered Interface Enabling Air-Stable and Dendrite-Free Lithium Metal Anode

Lithium (Li) metal, as a promising candidate for next-generation energy storage systems, suffers from an extremely unstable interface that is prone to crack, causing serious corrosion of Li metal and dendrite growth. To address this, a novel dual-layered interface on the Li metal anode is reported, which is featured with organics ( COPO₃ ,  (CO)₂PO₂ , and  (CO)₃PO) on the top and inorganics (Li₃PO₄) at the bottom. The flexible organic layer with reduced Young's modulus (≈550 MPa) contributes to maintain structural integrity, while the rigid inorganic layer with improved Young's modulus of ≈12 GPa is beneficial to suppress the Li dendrite growth. Accordingly, the protected Li is stabilized to maintain successive electrodeposition over 800 cycles of plating/stripping process at a current density of 2 mA cm⁻². Furthermore, the uniform dual-layered interface tends to prevent the corrosion of air to Li metal, exhibiting almost the same performance as the Li metal treated in the inert atmosphere.     

Superior Stable and Long Life Sodium Metal Anodes Achieved by Atomic Layer Deposition

Na‐metal batteries are considered as the promising alternative candidate for Li‐ion battery beneficial from the wide availability and low cost of sodium, high theoretical specific capacity, and high energy density based on the plating/stripping processes and lowest electrochemical potential. For Na‐metal batteries, the crucial problem on metallic Na is one of the biggest challenges. Mossy or dendritic growth of Na occurs in the repetitive Na stripping/plating process with an unstable solid electrolyte interphase layer of nonuniform ionic flux, which can not only lead to the low Coulombic efficiency, but also can create short circuit risks, resulting in possible burning or explosion. In this communication, the atomic layer deposition of Al₂O₃ coating is first demonstrated for the protection of metallic Na anode for Na‐metal batteries. By protecting Na foil with ultrathin Al₂O₃ layer, the dendrites and mossy Na formation have been effectively suppressed and lifetime has been significantly improved. Furthermore, the thickness of protective layer has been further optimized with 25 cycles of Al₂O₃ layer presenting the best performance over 500 cycles. The novel design of atomic layer deposition protected metal Na anode may bring in new opportunities to the realization of the next‐generation high energy‐density Na metal batteries.     

Uniform Lithium Nucleation/Growth Induced by Lightweight Nitrogen‐Doped Graphitic Carbon Foams for High‐Performance Lithium Metal Anodes

The lithium metal anode has attracted soaring attention as an ideal battery anode. Unfortunately, nonuniform Li nucleation results in uncontrollable growth of dendritic Li, which incurs serious safety issues and poor electrochemical performance, hindering its practical applications. Herein, this study shows that uniform Li nucleation/growth can be induced by an ultralight 3D current collector consisting of in situ nitrogen‐doped graphitic carbon foams (NGCFs) to realize suppressing dendritic Li growth at the nucleating stage. The N‐containing functional groups guide homogenous growth of Li nucleus nanoparticles and the initial Li nucleus seed layer regulates the following well‐distributed Li growth. Benefiting from such favorable Li growth behavior, superior electrochemical performance can be achieved as evidenced by the high Coulombic efficiency (≈99.6% for 300 cycles), large capacity (10 mA h cm^?2, 3140 mA h g^?1_NGCF‐Li), and ultralong lifespan (>1200 h) together with low overpotential (<25 mV at 3 mA cm^?2); even under a high current density up to 10 mA cm^?2, it still displays low overpotential of 62 mV.     

A Lightweight 3D Cu Nanowire Network with Phosphidation Gradient as Current Collector for High‐Density Nucleation and Stable Deposition of Lithium

Lithium metal anodes with high energy density are important for further development of next‐generation batteries. However, inhomogeneous Li deposition and dendrite growth hinder their practical utilization. 3D current collectors are widely investigated to suppress dendrite growth, but they usually occupy a large volume and increase the weight of the system, hence decreasing the energy density. Additionally, the nonuniform distribution of Li ions results in low utilization of the porous structure. A lightweight, 3D Cu nanowire current collector with a phosphidation gradient is reported to balance the lithiophilicity with conductivity of the electrode. The phosphide gradient with good lithiophilicity and high ionic conductivity enables dense nucleation of Li and its steady deposition in the porous structure, realizing a high pore utilization. Specifically, the homogenous deposition of Li leads to the formation of an oriented texture on the electrode surface at high capacities. A high mass loading (≈44 wt%) of Li with a capacity of 3 mAh cm^?2 and a high average Coulombic efficiency of 97.3% are achieved. A lifespan of 300 h in a symmetrical cell is obtained at 2 mA cm^?2, implying great potential to stabilize lithium metal.