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Lithium (Li) metal has emerged as a viable alternative anode material to address the current energy density shortfalls in Li batteries. However, its integration into widespread implementation remains somewhat constrained due to the substandard reversibility issues and safety concerns arising from erratic Li deposition. To effectively tackle these obstacles, considerable endeavors have been exerted to modulate the morphology of Li deposition. Nevertheless, it is exceedingly challenging for Li nuclei that tend to dendritic growth thermodynamically to transform into dense Li morphologies during their growth process. Therefore, it is crucial to understand what influences the formation process of Li nuclei and how to improve the state of Li nuclei. Herein, Li nucleation mechanisms involving mass transport across the solid electrolyte interface from electrolyte to electrode and electrode interfacial reactions are elucidated. Inspired by the understanding of Li nucleation, the corresponding design principles, including enhancing and homogenizing mass transport, stabilizing solid electrolyte interface film, and regulating surface interaction/selection, are summarized for optimizing Li nucleation and further inducing dendrite‐free Li deposition. In light of the competition among these design principles, a perspective on the existing challenges and opportunities for further promoting the application of Li metal batteries is proposed. [ABSTRACT FROM AUTHOR]

Li‐rich Mn‐based layered oxides (LRLO) are considered promising cathode candidates for high‐energy‐density lithium‐ion batteries (LIBs). However, severe capacity/voltage fading and poor rate performance hinder their practical application. Herein, a microstructure engineering strategy is put forward to design the unique bayberry‐like Li1.2Mn0.54Co0.13Ni0.13O2 (LRLO‐S) cathode material, composed of a spherical core and the shell self‐assembled by radially oriented nanorods with intrinsic rapid electron and ion transport capability, benefiting to increase the electrochemical reaction kinetics during cycling. Meanwhile, the radial texturing of the nanorods in shell layer forms a natural protective interface constituted by thermodynamically stable (003) planes, resisting electrolyte corrosion effectively. Furthermore, the configuration of orderly self‐assembled nanorods can effectively regulate the stress and strain to stabilize the lattice framework, finally improves the cycling stability of LRLO. As a result, the elaborately designed LRLO‐S cathode delivers remarkable high‐rate long‐term cycling stability with high capacity retentions of 91.2% after 500 cycles at 1 C and of 81.3% after 1000 cycles at 5 C. More importantly, the voltage stability is enhanced greatly with a superior retention of 89.6% after cycling 500 times at 1 C. Here a valuable strategy is provided to develop intrinsic mechanically robust high‐performance Li‐rich‐layered cathode materials for advanced LIBs. [ABSTRACT FROM AUTHOR]

Metal–organic framework‐derived metal phosphides with high capacity, facile synthesis, and morphology‐controlled are considered as potential anodes for lithium/sodium‐ion batteries. However, the severe volume expansion during cycling can cause the electrode material to collapse and reduce the cycle life. Here, novel CoP‐C@MoS2/C nanocube composites are synthesized by vapor‐phase phosphating and hydrothermal process. As the anode of LIBs, CoP‐C@MoS2/C exhibits outstanding long‐cycle performance of 369 mAh g−1 at 10 A g−1 after 2000 cycles. In SIBs, the composite also displays excellent rate capability of 234 mAh g−1 at 5 A g−1 and an ultra‐high the capacity retention rate of 90.16% at 1 A g−1 after 1000 cycles. Through density functional theory, it is found that the S ions and P ions at the interface formed by CoP and MoS2 can serve as Na+/Li+ diffusion channels with an action of van der Waals force, have attractive characteristics such as high ion adsorption energy, low expansion rate and fast diffusion kinetics compared with MoS2. This study provides enlightenment for the reasonable design and development of lithium/sodium storage anode materials composited with MOF‐derived metal phosphides and metal sulfides. [ABSTRACT FROM AUTHOR]

Potassium‐ion batteries (PIBs) are promising alternatives to lithium‐ion batteries because of the advantage of abundant, low‐cost potassium resources. However, PIBs are facing a pivotal challenge to develop suitable electrode materials for efficient insertion/extraction of large‐radius potassium ions (K+). Here, a viable anode material composed of uniform, hollow porous bowl‐like hard carbon dual doped with nitrogen (N) and phosphorus (P) (denoted as N/P‐HPCB) is developed for high‐performance PIBs. With prominent merits in structure, the as‐fabricated N/P‐HPCB electrode manifests extraordinary potassium storage performance in terms of high reversible capacity (458.3 mAh g−1 after 100 cycles at 0.1 A g−1), superior rate performance (213.6 mAh g−1 at 4 A g−1), and long‐term cyclability (205.2 mAh g−1 after 1000 cycles at 2 A g−1). Density‐functional theory calculations reveal the merits of N/P dual doping in favor of facilitating the adsorption/diffusion of K+ and enhancing the electronic conductivity, guaranteeing improved capacity, and rate capability. Moreover, in situ transmission electron microscopy in conjunction with ex situ microscopy and Raman spectroscopy confirms the exceptional cycling stability originating from the excellent phase reversibility and robust structure integrity of N/P‐HPCB electrode during cycling. Overall, the findings shed light on the development of high‐performance, durable carbon anodes for advanced PIBs. [ABSTRACT FROM AUTHOR]