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• An N-doped CNT-interspersed hierarchical carbon shell structure by Co-Zn bimetallic ZIFs-triggered surface polymerization of dopamine has been designed and successfully prepared for stabilized silicon anode (PDA@CoZn-NC@Si). • PDA@CoZn-NC@Si electrodes deliver better cycle stability of 814 mAh/g at 0.5C with a capacity loss of −0.14% per cycle over 400 cycles and possess excellent rate capability. • The solution-based chemical prelithiation method is used to compensate for irreversible loss of anode capacity, and the full cell exhibits an improved ICE (88.3%) and a higher energy density (419.8 Wh kg−1). The application of silicon-based anode remains a serious challenge due to its intrinsic volumetric expansion effect and low conductivity. In our work, a novel CNT-interspersed hierarchical carbon shell structure (denoted as PDA@CoZn-NC@Si) is synthesized by wrapping Si uniformly in the bimetallic zeolite imidazolate frameworks (ZIFs) and then encapsulated with a dopamine-derived carbon shell. The PDA@CoZn-NC@Si anode delivers better cycle stability of 814 mAh/g at 0.5C for 400 cycles (only −0.14% capacity reduction per cycle) and possesses excellent rate capability, which benefits from the inner porous buffer spaces, interspersed CNT, and solid heterogeneous carbon shells. In addition, the full cell is assembled by pairing a solution-based chemically prelithiated PDA@CoZn-NC@Si anode with a Li(Ni 1/3 Co 1/3 Mn 1/3)O 2 (NCM111) cathode, and it presents an improved initial coulombic efficiency (88.3%) and a high energy density (419.8 Wh/kg). This study provides effective guidance for optimizing the microstructure design and prelithium of Si-based anodes. [ABSTRACT FROM AUTHOR]

It is highly important to develop high-performance sulfur cathode to solve low areal sulfur loading, shuttling and sluggish conversion of polysulfides for lithium-sulfur batteries. Herein, a three-dimensional (3D) freestanding framework configured with Co nanoparticles and Co-N x codoped carbon nanotubes anchored in a carbon foam is synthesized and investigated as a new type of sulfur host. Such an architecture can serve not only as a conductive carbon networks but also as host scaffold for high sulfur-containing electrodes. The hierarchical porous structures cooperated with high density and dispersion multifunctional Co-N x species can efficiently trap and manipulate catalytic conversion kinetics of polysulfides. Benefiting from above characteristics, the designed cathodes exhibit a high capacity (1259 mA h g−1) at 0.1 C and excellent cycling performance with an ultralow decay of 0.038% per cycle over 500 cycles at a high current density of 3 C. Even with a high sulfur loading (7.0 mg cm−2) and lean electrolyte (E/S = 5 μL mg−1) operation, a high areal capacity of 4.34 mA h cm−2 is still achieved after 100 cycles at 0.1 C. This work provides a low-cost route for preparation of freestanding cathode materials toward highly efficient lithium-sulfur batteries. [Display omitted] • The 3D freestanding material is flexible, compressible and can be directly used as a cathode for Li-S batteries. • Co-N x species can chemically anchor and catalytically manipulate conversion kinetics of polysulfides. • The cathode exhibits a high capacity of 1259 mA h g−1 at 0.1 C, excellent long-cycle performance with an ultralow decay of 0.038% at 3 C. • A high areal capacity of 4.34 mA h cm−2 is achieved for a high sulfur loading of 7.0 mg cm−2, and lean electrolyte (E/S = 5 μL mg−1). [ABSTRACT FROM AUTHOR]

Potentially useful anodic material with prospects for use within rechargeable lithium-ion batteries are fabricated from silicon (Si)-based compounds. The active Si/electrolyte contact and weak conductivity, however, constantly produce side reactions, which dramatically reduce cycling stability. The only metallic current collector that demonstrates to facilitate lithium-ion transfer and electron conduction without alloying reactions is copper (Cu). In this study, we created Si-based multicomponent anode materials made of Si/Cu/Cu 3 Si alloy nanoparticles (Si/Cu/Cu 3 Si@C) coated in amorphous carbon. This is accomplished utilizing a straightforward, low-cost approach that combines hydrothermal technology and high-intensity ball milling. To further increase conductivity, Si/Cu/Cu 3 Si alloy is used as the active component. Through the use of a micro-sized amorphous carbon-coated structure, the volume problem of the active material can be successfully resolved. Additionally, the micro-sized amorphous carbon may inhibit nanoparticle agglomeration and alloy interfacial side reactions. As a result, it is anticipated that the Si/Cu/Cu 3 Si@C composite will display favorable electrochemical performances and possess a remarkable reversible specific capacity of 984 mAh g−1 at 0.5 C. The GITT test is used to determine the D Li + of the Si/Cu/Cu 3 Si@C electrode, which ranges from 10−11 to 10−8 cm−2 s−1. Additionally, the full-cell is constructed by coupling a Li(Ni 1/3 Co 1/3 Mn 1/3)O 2 (NCM111) cathode with a solution-based chemically Si/Cu/Cu 3 Si@C anode that exhibits an enhanced initial coulombic efficiency (84.9%) and outstanding cycle performance. • Si-based multicomponent anode materials made of Si/Cu/Cu 3 Si alloy nanoparticles (Si/Cu/Cu 3 Si@C) coated in amorphous carbon. • In-situ encapsulation of Si/Cu/Cu 3 Si alloy forming sucrose derived carbon have been developed to improve the performance and retain the structural integrity of the electrode. • Cu/Cu 3 Si alloy help to reduce internal electrical resistance and suppress the volume expansion of Si-based electrodes, which results in the extended life of Si-based LIBs. • The full-cell with the chemical prelithiated anode and Li(Ni 1/3 Co 1/3 Mn 1/3)O 2 cathode delivers a high 85% capacity retention after 200 cycles. [ABSTRACT FROM AUTHOR]

Water electrolysis has been acknowledged as a renewable, scalable, and effective way of producing hydrogen. However, for water splitting, efficient and noble metal-free electrocatalysts were lacking. Here, a Co–Ni–Zn porous three-dimension N-doped carbonization structure on the carbon nanotube film (CNTF) was synthesized through a metal organic frameworks (MOFs) annealing procedure. The porous morphology, caused by the evaporation of zinc at high temperatures, enhances the interaction between the catalysts and electrolyte, and the self-supporting structure minimizes the contact resistance between the catalysts and the substrate, which reduces obstructions during current flow. More active sites, multiple mesopores, and high conductivity are all features of this composite structure. It can achieve a small overpotential of 112 mV and 270 mV at a current density of 10 mA cm−2, respectively, for hydrogen and oxygen evolution reactions (HER and OER). At a current density of 10 mA cm−2, the Co–Ni–Zn/NCNTF has an external voltage of 1.58 V and is very durable for overall water splitting. [Display omitted] • Ni- and Zn-doped MOFs grow in-situ on a CNT film. • Zn doping increases contact area between catalysts and electrolyte. • A self-supporting structure minimizes the contact resistance. • This catalyst is an efficient bifunctional catalyst. [ABSTRACT FROM AUTHOR]

• Optimal channel features were obtained by analyzing channel heat flow performance. • Improved cooling efficiency through agent model and algorithm optimization. • Arcing greatly improved the comprehensive performance of liquid cooled plates. • The optimized average temperature and pressure drop were reduced by 0.36°C and 132.43Pa. The battery thermal management system (BTMS) is an important guarantee that the batteries of new energy vehicles work efficiently and safely, so it is particularly important to design a liquid cooling channel with good cooling performance and low power consumption. Based on 6 types of common local channel geometries (square, triangular, diamond, trapezoid, hexagonal, etc.), 24 types of liquid-cooled plate channel structures were proposed by adding V- and X-shaped differential flow channel inside. Analyzed the flow characteristics, pressure drop and heat transfer characteristics of the 24 different types of liquid-cooled channels, to clarify the reasons for the differences in heat dissipation level and pressure drop of each type of micro channel, and to obtain the optimal channel types. For the structural parameters of the optimal channel types, the NSGA-II algorithm was used for multi-objective optimization. Compared to CFD simulation results, the relative errors were within 3%. To further improve the comprehensive performance of the liquid-cooled plate, the optimized model would be analyzed for channel arcing. The optimized results showed an average temperature reduction of 0.36°C (1.01%) and a pressure drop reduction of 132.43Pa (64.72%) compared to the base model. The optimal channel features obtained in this study will provide a reference for the selection of channel types and local feature optimization. [ABSTRACT FROM AUTHOR]

• The influence of radial structure on magnification performance was studied. • The effect of coating layer on the stability of composite electrode was studied. • B-NCM@LNO5 cathode exhibited a high rate and long cycle durability. Nickel-rich cathode materials play a pivotal role in the functioning of lithium-ion batteries, but their crystal structure defects and surface side reactions significantly affect battery performance. This has slowed down the commercialization process of nickel-rich cathodes. To remedy these problems, a new strategy utilizing B and Nb for crystal structure and interface control of LiNi 0.8 Co 0.1 Mn 0.1 O 2 (NCM811) is proposed in this study. The B Nb modified cathode exhibits strong radial orientation and exposes a large number of active (003) lattice plane on the particle surface. This structural control reduces micro-cracks and accelerates lithium-ion diffusion kinetics. Additionally, the LiNbO 3 coating effectively avoids immediate contact between secondary particles and the electrolyte, greatly alleviating side reactions. Consequently, the optimal cathode B-NCM@LNO5 modified cathode maintains a capacity retention of 86.71% after 200 cycles at 1 C, outperforming the original material (76.11% retention). Meanwhile, it demonstrates attractive rate capability of 158.4 mAhg−1 under 5 C. This research provides valuable insights for addressing anisotropic strain and interface compatibility issues in nickel-rich cathodes. [ABSTRACT FROM AUTHOR]