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This paper investigates the coordinated behaviour of the multiple Euler–Lagrange systems under diverse interactions with time delays. Specially, in the case of undirected interconnection, the proportional plus damping control strategy is proposed and the sufficient conditions of bipartite consensus are derived via energy function based approach. Subsequently, a velocity‐free controller is further developed by introducing a novel second‐order auxiliary system to each agent. In the case of directed network, by fully investigating the property of the Laplacian matrix associated with the cooperative–competitive interactions, a bipartite consensus controller is devised and the input–output property analysis of the system transfer function in frequency domain is presented. Simulation results are provided to demonstrate the effectiveness of the presented algorithms. [ABSTRACT FROM AUTHOR]

Li metal batteries have attracted extensive research attention because of their extremely high theoretical capacity. However, the commercialization of the Li metal batteries is hindered, as uncontrolled Li dendrites growth leads to safety concerns and a low coulombic efficiency. To suppress Li dendrites growth and achieve dense Li deposition, a lithiophilic 3D Cu host is designed for Li metal anode, in which the nano‐sized Cu is in situ formed with the aid of infused Li metal. The fabricated Li metal anode exhibit a superior electrochemical stability than raw Li metal anode, and compact Li is maintained during cycling. The experimental results and density functional theory calculations demonstrate that the nano‐sized Cu formed on the surface of the skeleton host shows highly exposed Cu (100) and Cu (110) surfaces, which exhibits a strong affinity toward Li, and effectively eliminates the formation of Li dendrites, leading to a dense Li deposition. With the strategy of adjusting exposed surfaces of Cu host, the optimized Li metal anode enhances the electrochemical performance of full cells, and concomitantly demonstrates their potential for future designs of next‐generation Li metal anodes or Li‐free anodes for Li metal batteries. [ABSTRACT FROM AUTHOR]

Lithium–sulfur batteries are promising energy‐storage devices because of their high theoretical energy densities. For practical Li–S batteries, reducing the amount of electrolyte used is essential for achieving the high energy densities. However, reducing the electrolyte amount leads to severe performance degradation, mainly because of sluggish deposition of discharge products (Li2S) and the accompanying passivation issue that arise from the insulating nature of Li2S. In this study, a lightweight, robust interlayer, with a 3D open structure and a low surface area is designed and fabricated. The structure facilitates electrolyte infiltration without trapping too much electrolyte. Moreover, the electrocatalytic Co nanoparticles embedded in the skeleton surface within the interlayer effectively promote Li ion diffusion, polysulfides conversion, and Li2S deposition, and therefore enhance the electrochemical kinetics under lean electrolyte conditions. The mechanisms involved in the interlayer effects are investigated by microstructural characterizations, electrochemical performance tests, density functional theory calculations, and in situ X‐ray diffraction characterization. These results show the feasibility of using an interlayer strategy to improve the electrochemical performances of Li–S batteries under lean electrolyte conditions to potentially increase the practical energy densities of Li–S batteries. [ABSTRACT FROM AUTHOR]

Summary: This paper addresses the control issue for cooperative visual servoing manipulators on strongly connected graph with communication delays, in which case that the uncertain robot dynamics and kinematics, uncalibrated camera model, and actuator constraint are simultaneously considered. An adaptive cooperative image‐based approach is established to overcome the control difficulty arising from nonlinear coupling between visual model and robot agents. To estimate the coupled camera‐robot parameters, a novel adaptive strategy is developed and its superiority mainly lies in the containment of both individual image‐space errors and the synchronous errors among networked robots; thus, the cooperative performance is significantly strengthened. Moreover, the proposed cooperative controller with a Nussbaum‐type gain is implemented to both globally stabilize the closed‐loop systems and realize the synchronization control objective under the existence of unknown and time‐varying actuator constraint. Finally, simulations are carried out to validate the developed approach. [ABSTRACT FROM AUTHOR]

Considering the market demand for lithium‐ion batteries (LIBs) and sodium‐ion batteries (SIBs) as energy storage devices, it is necessary to find a negative electrode material with low cost, high specific capacity, and long cycle life. CuO has a high theoretical specific capacity and therefore has broad application prospects. This study reports a freestanding nitrogen‐doped carbon‐coated CuO array (NC‐CuO)‐based anode obtained by synthesizing CuO nanorods on a Cu net and depositing nitrogen‐doped carbon on the surface of the nanorods. The NC‐CuO array anode fully utilizes the synergistic advantages of the 3D array and the outer N‐doped carbon layer, which effectively enhance the electronic conductivity of the metal oxide and alleviate the volume change during Li/Na ion insertion and extraction. It is found that the NC‐CuO array as the anode material for LIBs has a capacity of 562.5 mAhg−1 and a cycle stability of more than 200 cycles even at a high current density of 500 mAg−1. SIBs with the NC‐CuO array anode also exhibit excellent electrochemical performance. [ABSTRACT FROM AUTHOR]