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Abstract Constructing composite solid electrolytes (CSEs) integrating the merits of inorganic and organic components is a promising approach to developing high‐performance all‐solid‐state lithium metal batteries (ASSLMBs). CSEs are now capable of achieving homogeneous and fast Li‐ion flux, but how to escape the trade‐off between mechanical modulus and adhesion is still a challenge. Herein, a strategy to address this issue is proposed, that is, intercalating highly conductive, homogeneous, and viscous‐fluid ionic conductors into robust coordination laminar framework to construct laminar solid electrolyte with homogeneous and fast Li‐ion conduction (LSE‐HFC). A 9 µm‐thick LSH‐HFC, in which poly(ethylene oxide)/succinonitrile is adsorbed by coordination laminar framework with metal–organic framework nanosheets as building blocks, is used here as an example to determine the validity. The Li‐ion transfer mechanism is verified and works across the entire LSE‐HFC, which facilitates homogeneous Li‐ion flux and low migration energy barriers, endowing LSE‐HFC with high ionic conductivity of 5.62 × 10−4 S cm−1 and Li‐ion transference number of 0.78 at 25 °C. Combining the outstanding mechanical strength against punctures and the enhanced adhesion force with electrodes, LSE‐HFC harvests uniform Li plating/stripping behavior. These enable the realization of high‐energy‐density ASSLMBs with excellent cycling stability when being assembled as LiFePO4/Li and LiNi0.6Mn0.2Co0.2O2/Li cells.

Cathode materials have been playing an important role in the development of high-energy, safe and low-cost lithium-ion batteries. However, the widely used single-phase cathode materials are facing great challenges in solving the mileage and safety problems related to electric vehicles due to their inherent structural defects. Intergrown design of bulk structure is believed to be one of the most fundamental ways to improve structural stability and capacity for cathode materials. Due to the diversity of structural configurations, the systematic understanding is still lack for the intergrown structures of different combinations. Therefore, it is very desirable, but also of great importance to summarize the current progress and challenges for intergrown cathodes. In this review, we comprehensively reviewed the design and synthesis methods of intergrown cathodes including layered-spinel intergrown structures, layered-rocksalt intergrown structures, and spinel-rocksalt intergrown structured cathode materials. The charge compensation mechanism of intergrown cathodes with different structural configurations was analyzed in depth, and a targeted optimization schematic diagram was also proposed. Finally, combined with advanced characterization techniques, the understanding of the structural changes has been deepened for the intergrown cathodes during the electrochemical process. It is hoped this review should shed light on the development of advanced cathode materials for the next-generation Li-ion batteries.

Tremendous studies have been engaged in exploring the application of solid-state electrolytes (SSEs) as it provides opportunities for next-generation batteries with excellent safety and high energy density. Among the existing SSEs, newly developed halide SSEs have become a hot spot owing to their high ionic conductivity up to 1 mS cm−1 and their stability against high-voltage cathode. As a result, halide SSEs have been shown to be promising candidates for all-solid-state lithium batteries (ASSLBs). Here, we review the progress of halide SSEs and available modification strategies of halide SSE-based batteries. First, halide SSEs are divided into four different categories, including halide SSEs with divalent metal, trivalent metal, tetravalent metal, and non-metal central elements, to overview their progress in the studies of their ionic conductivity, crystal structure, conductive mechanism, and electrochemical properties. Then, based on their existing drawbacks, three sorts of modification strategies, classified as chemical doping, interfacial modification, and composite electrolytes, along with their impacts on halide SSE-based batteries, are summarized. Finally, some perspectives toward halide SSE research are put forward, which will help promote the development of halide SSE-based batteries.

Layered Li-rich oxides have attracted much attention because of higher capacity than that of traditional layered oxides (more than 250 mAh g−1). However, the intrinsic issues of Li-rich cathode materials suffer from lattice oxygen loss, poor rate capability, voltage fade, and limited cycle life. To tackle these problems, the Li-rich cathode containing intergrown layer and spinel phases was proposed, and this heterostructure material meets the requirements of high energy and stable surface with a fast Li+ diffusion channel. Herein, we review the recent progress and in-depth understanding about heterostructure including microstructure and morphology, performance of advancement and degradation mechanisms, and modification strategies. Special attention is given to the high-performance energy mechanism as follows: (a) spinel phase and oxygen vacancy jointly enhance the lattice structure and prevent the irreversible oxygen release, (b) higher capacity is achieved by promotion of activation of Li2MnO3 phase and control of the activation rate to realize stable long-term cyclability, and (c) spinel phase provides the 3D interconnected Li+ diffusion channels and protects the surface region from side reactions. The other issue that aroused interest is the undesirable changes of phase transition and degradation mechanisms as follows: (a) the key reconstruction process is to produce a “good” spinel to maintain the surface and interior structure stability. (b) It is significant to figure out the structure degradation and phase transition mechanism in the cycled heterostructure. This review aims to provide inspiration and opportunities for the design of high-energy-density cathode materials, thereby bridging the gap between laboratory research and practical battery applications.

Abstract As an important part of electric vehicles, lithium-ion battery packs will have a certain environmental impact in the use stage. To analyze the comprehensive environmental impact, 11 lithium-ion battery packs composed of different materials were selected as the research object. By introducing the life cycle assessment method and entropy weight method to quantify environmental load, a multilevel index evaluation system was established based on environmental battery characteristics. The results show that the Li–S battery is the cleanest battery in the use stage. In addition, in terms of power structure, when battery packs are used in China, the carbon footprint, ecological footprint, acidification potential, eutrophication potential, human toxicity cancer and human toxicity noncancer are much higher than those in the other four regions. Although the current power structure in China is not conducive to the sustainable development of electric vehicles, the optimization of the power structure is expected to make electric vehicles achieve clean driving in China.

Abstract Achieving satisfactory performance for a solid‐state Na‐metal battery (SSNMB) with an inorganic solid electrolyte (SE), especially under freezing temperatures, poses a challenge for stabilizing a Na‐metal anode. Herein, this challenge is addressed by utilizing a Natrium super ionic conductor (NASICON) NASICON‐type solid electrolyte, enabling the operation of a rechargeable SSNMB over a wide temperature range from −20 to 45 °C. The interfacial resistance at the Na metal/SE interface is only 0.4 Ω cm2 at 45 °C and remains below 110 Ω cm2 even at −20 °C. Remarkably, long‐term Na‐metal plating/stripping cycles lasting over 2000 h at −20 °C are achieved with minimal polarization voltages at 0.1 mA cm−2. Further analysis reveals the formation of a uniform Na3−xCaxPO4 interphase layer at the interface, which significantly contributes to the exceptional interfacial performance observed. By employing a Na3V1.5Al0.5(PO4)3 cathode, the full battery system demonstrates excellent adaptability to low temperatures, exhibiting a capacity of 80 mA h g−1 at −20 °C over 50 cycles and retaining a capacity of 108 mAh g−1 (88.5% of the capacity at 45 °C) at 0 °C over 275 cycles. This research significantly reduces the temperature threshold for SSNMB operation and paves the way toward solid‐state batteries suitable for all‐season applications.

This paper based on the first-principles simulations sheds light on the chalcogenide-defected behavior of the Janus SnSSe monolayer and the sensing property of the defected-SnSSe monolayer upon three typical thermal runaway fault gases, namely H2, CO and C2H2. Results indicate that the Se-vacancy is more likely to be formed in a SnSSe monolayer, and the Se–SnSSe monolayer performs physisorption, with adsorption energies of −0.14, −0.61 and −0.37 eV for three systems, and electron-donating property, contributing 0.047, 0.087 and 0.070 e to such three gases. The band structure and work function analyses reveal the desirable potential of Se–SnSSe monolayer as a resistance-type or WF-based sensor for CO detection. Also, the recovery property is analyzed to consider the reusability of such sensing material. Besides, the applied biaxial strains reveal that Se–SnSSe monolayer performs high and tunable sensitivity for these gas species, especially for H2 and C2H2 detections. This work paves the way to explore SnSSe-based material for gas sensing application in many typical fields involving H2, CO and C2H2 detection, which is also guidable to explore the sensing potential of many other Janus 2D materials.

For solid-state electrolyte in lithium-ion batteries, high crystal boundary impedance leads to tough electrolyte-electrode interfacial issues. Here, we introduce garnet Li6.4La3Zr1.4Ta0.6O12 (LLZTO) nanoparticles and succinonitrile (SN) into thermal polyurethane (TPU) to fabricate a composite solid-state electrolyte (TPU/LLZTO/SN), achieving high ionic conductivity of 6.452 × 10−4 S cm−1. The TPU polymer with specific soft and hard segments allows lithium ions fast transport and holds good mechanical strength as the electrolyte matrix. The ionic conductor LLZTO further improves the ionic conductivity and mechanical property of the composite electrolyte membrane. Additional SN supplies the electrolyte’ wide electrochemical stabilization window, and enhances the metallic lithium compatibility of the TPU matrix. As a result, the as prepared TPU/LLZTO/SN electrolyte presents high lithium ions transference number of 0.64, and also good mechanical property.

Layered Ni-rich materials for lithium-ion batteries exhibit high discharge capacities but degraded cyclability at the same time. The limited cycling stability originates from many aspects. One of the critical factors is the intrinsic insulating residual lithium compounds and the rock-salt (NiO) phase on the surface of particles. In this work, LiNi0.8Co0.1Mn0.1O2 material is etched with a trace amount of boric acid and used as a model to demonstrate the influences of weak acid treatment on the surface phase regulations. After the etching process, the pH of the material is reduced from 12.08 to 11.82, along with a lower cation mixing degree and promoting electrochemical performances. Corresponding measurements demonstrate that weak acids such as H3BO3 can also etch the NiO phase on the surface to adjust the surface of the particles to a pure layered structure. This process improves the lithium-ion diffusion and electron transport in the interface between material and electrolyte, consequently leading to better cycling performance and rate capability. This study provides a novel strategy and comprehensive understanding of acid modification and surface phase regulation process of Ni-rich cathode materials for lithium-ion batteries.

High-capacity Li-rich oxide materials have received extensive attention due to their unique anion–cation charge compensation involvement. However, the high operating voltage, poor cycling performance, unsafe oxygen evolution, and voltage decay limit their industrial application. The emergence and development of solid-state batteries offer a great opportunity to solve these issues by replacing flammable and unstable liquid electrolytes with solid electrolytes. Meanwhile, utilization of high-capacity Li-rich oxide cathodes enables to establish high-energy-density solid-state batteries with wide voltage ranges, light weight, and high mechanical properties. This review summarizes the recent progress of Li-rich oxide materials and solid electrolytes, emphasizing their major advantages, interface challenges, and modification approaches in the development of Li-rich solid-state batteries. We also propose possible characterization strategies for effective interfacial observation and analyses. It is hoped that this review should inspire the rational design and development of better solid-state batteries for application in portable devices, electric vehicles, as well as power grids.

Abstract Background Black pepper (Piper nigrum L.), an important and long-cultivated spice crop, is native to South India and grown in the tropics. Piperine is the main pungent and bioactive alkaloid in the berries of black pepper, but the molecular mechanism for piperine biosynthesis has not been determined. MicroRNAs (miRNAs), which are classical endogenous noncoding small RNAs, play important roles in regulating secondary metabolism in many species, but less is known regarding black pepper or piperine biosynthesis. Results To dissect the functions of miRNAs in secondary metabolism especially in piperine biosynthesis, 110 known miRNAs, 18 novel miRNAs and 1007 individual targets were identified from different tissues of black pepper by small RNA sequencing. qRT-PCR and 5′-RLM-RACE experiments were conducted to validate the reliability of the sequencing data and predicted targets. We found 3 miRNAs along with their targets including miR166-4CL, miR396-PER and miR397-CCR modules that are involved in piperine biosynthesis. Conclusion MiRNA regulation of secondary metabolism is a common phenomenon in plants. Our study revealed new miRNAs that regulate piperine biosynthesis, which are special alkaloids in the piper genus, and they might be useful for future piperine genetic improvement of black pepper.

The severe “shuttle effect” of dissolved polysulfide intermediates and the poor electronic conductivity of sulfur cathodes cause capacity decay of lithium–sulfur batteries and impede their commercialization. Herein, we synthesized a series of well-designed yolk-shelled Fe3O4@carbon (YS-Fe3O4@C) nanocavities with different proportions of Fe3O4 as efficient sulfur hosts to stabilize polysulfide intermediates. The yolk-shelled nanocavity architectures were prepared through a facile method, which could effectively confine the active materials and achieve high conductivity. The polysulfide intermediate shuttle was successfully suppressed by a physiochemical synergism effect combining the retention of carbon shells and the adsorption of Fe3O4 nanoparticle cores. The highly conductive carbon shell provides efficient pathways for fast electron transportation. Meanwhile, the visible evolution of active materials and a reversible electrochemical reaction are revealed by in situ X-ray diffraction. With the balanced merits of enhanced electrical conductivity of carbon shell and optimal adsorption of Fe3O4 cores, the S/YS-27Fe3O4@C cathode (Fe3O4 accounts for 27 wt% in YS-Fe3O4@C) had the best electrochemical performance, exhibiting a high reversible specific capacity of 731.9 mAh g−1 and long cycle performance at 1 C (capacity fading rate of 0.03% over 200 cycles).

The existence of residual lithium compounds (RLCs) on the surface of layered Ni-rich materials will deteriorate the electrochemical properties and cause safety problem. This work presents an effective surface washing method to remove the RLCs from LiNi0.90Co0.06Mn0.04O2 material surface, via ethyl alcohol solution that contains low concentration of boric acid. It is a low-cost process because the filter liquor can be recycled. The optimal parameters including washing time, boric acid concentration, and solid–liquid ratio were systematically studied. It has been determined by powder pH and Fourier transform infrared spectra results that the amount of RLCs was reduced effectively, and the storage performance was significantly enhanced for the washed samples. The 150th capacity retentions after storing had increased from 68.39% of pristine material to 85.46–94.84% of the washed materials. The performance enhancements should be ascribed to the surface washing process, which removed not only the RLCs, but also the loose primary particles effectively.

Environmentally friendly acid-leaching processes with three organic acids (maleic, glycolic and acetoacetic) were developed to recover valuable metals from the cathodic material of spent lithium-ion batteries (LiCoO2). The leaching efficiencies of Li and Co by the maleic acid were 99.58% and 98.77%, respectively. The leaching efficiencies of Li and Co by the glycolic acid were 98.54% and 97.83%, while those by the acetoacetic acid were 98.62% and 97.99%, respectively. The optimal acid concentration for the maleic acid-, glycolic acid- and acetoacetic acid-leaching processes were 1, 2 and 1.5 mol l–1, respectively, while their optimal H2O2 concentrations were 1.5, 2 and 1.5 vol%, respectively. The optimal solid/liquid ratio, temperature and reaction time for the leaching process of the three organic acids was the same (10 g l−1, 70°C, 60 min). The thermodynamic formation energy of the leaching products and the Gibbs free energy of the leaching reactions were calculated, and the kinetic study showed that the leaching processes fit well with the shrinking-core model. Based on the comparison in the leaching parameters, the efficacy and availability of the three acids is as follows: maleic acid > acetoacetic acid > glycolic acid.