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Modulating interfacial electrochemistry represents a prevalent approach for mitigating lithium dendrite growth and enhancing battery performance. Nevertheless, while most additives exhibit inhibitory characteristics, the accelerating effects on interfacial electrochemistry have garnered limited attention. In this work, perfluoromorpholine (PFM) with facilitated kinetics is utilized to preferentially adsorb on the lithium metal interface. The PFM molecules disrupt the solvation structure of Li + and enhance the migration of Li + . Combined with the benzotrifluoride, a synergistic acceleration-inhibition system is formed. The ab initio molecular dynamics (AIMD) and density functional theory (DFT) calculation of the loose outer solvation clusters and the key adsorption-deposition step supports the fast diffusion and stable interface electrochemistry with an accelerated filling mode with C─F and C─H groups. The approach induces the uniform lithium deposition. Excellent cycling performance is achieved in Li||Li symmetric cells, and even after 200 cycles in Li||NCM811 full cells, 80% of the capacity is retained. This work elucidates the accelerated electrochemical processes at the interface and expands the design strategies of acceleration fluorinated additives for lithium metal batteries., (© 2024 Wiley‐VCH GmbH.)

Gel electrolytes are gaining attention for rechargeable Zn-ion batteries because of their high safety, high flexibility, and excellent comprehensive electrochemical performances. However, current gel electrolytes still perform at mediocre levels due to incomplete Zn salts dissociation and side reactions. Herein, an electrostatic-induced dual-salt strategy is proposed to upgrade gel electrolytes to tackle intrinsic issues of Zn metal anodes. The competitive coordination mechanism driven by electrostatic repulsion and steric hindrance of dual anions promotes zinc salt dissociation at low lithium salt addition levels, improving ion transport and mechanical properties of gel electrolytes. Li + ions and gel components coordinate with H 2 O, reducing active H 2 O molecules and inhibiting associated side reactions. The dual-salt gel electrolyte enables excellent reversibility of Zn anodes at both room and low temperatures. Zn||Polyaniline cells using the dual-salt gel electrolyte exhibit a high discharge capacity of 180 mAh g -1 and long-term cycling stability over 180 cycles at -20 °C. The dual-salt strategy offers a cost-effective approach to improving gel electrolytes for high-performance flexible Zn-ion batteries., (© 2024 Wiley‐VCH GmbH.)

Organic electrode materials are promising for next-generation energy storage materials due to their environmental friendliness and sustainable renewability. However, problems such as their high solubility in electrolytes and low intrinsic conductivity have always plagued their further application. Polymerization to form conjugated organic polymers can not only inhibit the dissolution of organic electrodes in the electrolyte, but also enhance the intrinsic conductivity of organic molecules. Herein, we synthesized a new conjugated organic polymer (COPs) COP500-CuT 2 TP (poly [5,10,15,20-tetra(2,2'-bithiophen-5-yl) porphyrinato] copper (II)) by electrochemical polymerization method. Due to the self-exfoliation behavior, the porphyrin cathode exhibited a reversible discharge capacity of 420 mAh g -1 , and a high specific energy of 900 Wh Kg -1 with a first coulombic efficiency of 96 % at 100 mA g -1 . Excellent cycling stability up to 8000 cycles without capacity loss was achieved even at a high current density of 5 A g -1 . This highly conjugated structure promotes COP500-CuT 2 TP combined high energy density, high power density, and good cycling stability, which would open new opportunity for the designable and versatile organic electrodes for electrochemical energy storage., (© 2024 Wiley‐VCH GmbH.)

In recent years, gel-electrolyte becomes pivotal in preventing hydrogen evolution, reducing dendrite growth, and protecting the zinc metal anode for zinc-ion batteries. Herein, a polyvinyl alcohol-based water-organic hybrid gel electrolyte with Agar and dimethyl sulfoxide is designed to construct the spontaneous desaturation of the solvation sheath for reducing hydrogen evolution and dendrite growth at room temperature and even low temperature. According to experimental characterization and theoretical calculations, the well binding between multihydroxy polymer and H 2 O is achieved in the hybrid desaturated gel-electrolyte to regulate the inner and outer sheath. The ionic conductivity of hybrid gel-electrolyte reaches 7.4 mS cm -1 even at -20 °C with only 0.5 m zinc trifluoromethanesulfonate (Zn(OTf) 2 ). The Zn symmetric cells cycle over 1200 h under 26 and -20 °C with improved mechanical properties and electrochemical performance. The asymmetric Zn || Cu cell with hybrid gel electrolyte reaches ≈99.02% efficiency after 250 cycles. The capacity of full cell is maintained at around 74 mAh g -1 with almost unchanged retention rate from 50 to 300 cycles at -20 °C. This work provides an effective strategy for desaturated solvation to reach anti-freezing and high-density Zn energy storage devices., (© 2023 Wiley-VCH GmbH.)

Heterostructured materials integrate the advantages of adjustable electronic structure, fast electron/ions transfer kinetics, and robust architectures, which have attracted considerable interest in the fields of rechargeable batteries, photo/electrocatalysis, and supercapacitors. However, the construction of heterostructures still faces some severe problems, such as inferior random packing of components and serious agglomeration. Herein, a terminal group-oriented self-assembly strategy to controllably synthesize a homogeneous layer-by-layer SnSe 2 and MXene heterostructure (LBL-SnSe 2 @MXene) is designed. Benefitting from the abundant polar terminal groups on the MXene surface, Sn 2+ is induced into the interlayer of MXene with large interlayer spacing, which is selenized in situ to obtain LBL-SnSe 2 @MXene. In the heterostructure, SnSe 2 layers and MXene layers are uniformly intercalated in each other, superior to other heterostructures formed by random stacking. As an anode for lithium-ion batteries, the LBL-SnSe 2 @MXene is revealed to possess strong lithium adsorption ability, the small activation energy for lithium diffusion, and excellent structure stability, thus achieving outstanding electrochemical performance, especially with high specific capacities (1311 and 839 mAh g -1 for initial discharge and charge respectively) and ultralong cycling stability (410 mAh g -1 at 5C even after 16 000 cycles). This work conveys an inspiration for the controllable design and construction of homogeneous layered heterostructures., (© 2023 Wiley-VCH GmbH.)

Uncontrollable Li dendrite growth and low Coulombic efficiency severely hinder the application of lithium metal batteries. Although a lot of approaches have been developed to control Li deposition, most of them are based on inhibiting lithium deposition on protrusions, which can suppress Li dendrite growth at low current density, but is inefficient for practical battery applications, with high current density and large area capacity. Here, a novel leveling mechanism based on accelerating Li growth in concave fashion is proposed, which enables uniform and dendrite-free Li plating by simply adding thiourea into the electrolyte. The small thiourea molecules can be absorbed on the Li metal surface and promote Li growth with a superfilling effect. With 0.02 m thiourea added in the electrolyte, Li | Li symmetrical cells can be cycled over 1000 cycles at 5.0 mA cm -2 , and a full cell with LiFePO 4 | Li configuration can even maintain 90% capacity after 650 cycles at 5.0 C. The superfilling effect is also verified by computational chemistry and numerical simulation, and can be expanded to a series of small chemicals using as electrolyte additives. It offers a new avenue to dendrite-free lithium deposition and may also be expanded to other battery chemistries., (© 2019 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The lithium storage capacity of graphite can be significantly promoted by rare earth trihydrides (REH 3 , RE = Y, La, and Gd) through a synergetic mechanism. High reversible capacity of 720 mA h g -1 after 250 cycles is achieved in YH 3 -graphite nanocomposite, far exceeding the total contribution from the individual components and the effect of ball milling. Comparative study on LaH 3 -graphite and GdH 3 -graphite composites suggests that the enhancement factor is 3.1-3.4 Li per active H in REH 3 , almost independent of the RE metal, which is evident of a hydrogen-enhanced lithium storage mechanism. Theoretical calculation suggests that the active H from REH 3 can enhance the Li + binding to the graphene layer by introducing negatively charged sites, leading to energetically favorable lithiation up to a composition Li 5 C 16 H instead of LiC 6 for conventional graphite anode., (© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)