Baohua Li

Aqueous zinc ion batteries (ZIBs) are compelling candidates for grid energy storage due to their safety and cost-effectiveness. High-entropy electrolyte design is widely applied to improve the antifreezing capability and interfacial stability of ZIB; however, the neglected ion–solvent interactions jeopardize its practical adaptability as a guideline. Here, we propose the ion synergistic polarization index (SPI) as an effective descriptor, which exhibits a decisive correlation with electrolyte solidification behavior, outperforming traditional parameters. The SPI metric works by striking a critical balance between cationic perturbation strength with anionic polarization capability. Guided by this principle, we develop a high-SPI electrolyte with different cations. Integrated theoretical simulations and experimental characterizations confirm that the high-SPI electrolyte effectively inhibits water crystallization, maintaining a noncrystalline state even at a record-low temperature of −136.67 °C while delivering rapid ionic transport (an ionic conductivity of 2.4 mS cm^–1 at −60 °C) and robust interfacial stability. When tested at −60 °C, a Zn∥Zn symmetric cell enables ultrastable cycling for over 4800 h. Meanwhile a Zn∥polyaniline full cell retains 70% of its room-temperature capacity. These findings establish a generic framework for reconciling the trade-off between cryogenic operation and electrochemical stability hurdles in next-generation ZIBs and beyond (e.g., lithium-ion batteries).

Development of lithium batteries capable of operating over ultrawide temperature ranges, from subzero to temperatures ≥ 100 °C, is urgently needed yet remains highly challenging. This is primarily due to the inherent trade-off between sluggish kinetics at low temperatures and poor structural stability at high temperatures and high voltages. Herein, by systemically investigating the temperature responsiveness of various anions, a temperature-adaptive weakly solvating electrolyte (TAE) is elaborately designed in which the solvation structures are sensitive to temperature. As a result, TAE not only exhibits a higher Li⁺ transference number and ionic conductivity comparable to commercial electrolytes at ambient and subzero temperatures, but also leads to anion-derived gradient inorganic-rich interphases at high temperatures/cutoff voltages. Consequently, LiCoO₂ || Li cells using TAE achieve capacity retentions of 89.6% after 500 cycles at ambient temperature and a cutoff voltage of 4.5 V, and 90.8% after 450 cycles at 80 °C. Moreover, 6.5 Ah pouch lithium-ion cells using TAE, with enhanced safety and ultrawide temperature ranges from −30 to 130 °C, deliver a capacity retention of 86.1% after 100 cycles at 100 °C. Notably, even at 120 °C, the cells retain 71.1% of their initial capacity over 60 cycles without significant swelling. This strategy empowers lithium batteries to autonomously adapt to external temperature, enabling reliable operation across diverse extreme environments.

The practical application of poly(ethylene oxide) (PEO)-based polymer electrolytes in all-solid-state lithium-metal batteries (ASSLMBs) is severely restricted by their low energy density and uncontrolled lithium dendrite growth. Herein, we introduced a trace amount of MgI₂ as a dual-functional Janus additive that simultaneously addresses limited capacity and interfacial stability in PEO electrolytes. The Mg²⁺ competitively coordinates with both PEO chains and TFSI^- anions, effectively weakening the Li⁺-TFSI^- interaction and promoting Li⁺ dissociation, thereby increasing the free Li⁺ concentration and enhancing interfacial lithium-ion transport. Simultaneously, iodine species (I^-/I₃^-) participate in cathode redox reactions to enhance reversible capacity while facilitating the formation of a robust, inorganic-rich solid electrolyte interphase (SEI) at the anode, which effectively suppresses dendrite formation. As a result, the modified electrolyte delivers a recorded critical current density of 1.7 mA/cm², and Li||Li symmetric cells achieve ultralong cycling stability for over 10,000 h at 60 °C. A Li||LiFePO₄ full battery exhibits exceptional durability of 10 times that of the blank system, with 93.28% capacity retention at 1 C after 2000 cycles. More impressively, as-fabricated pouch cells demonstrate the capacity retention of 95.80% after 250 cycles at 60 °C. This work presents a facile and economically viable strategy to synergistically regulate additionally reversible capacity and interfacial chemistry for next-generation, high-performance ASSLMBs.

Temperature-resistant weakly solvating electrolytes (TRWSEs) are indispensable for lithium-metal batteries with ultrahigh energy density (≥450 Wh kg^-1) and excellent temperature adaptability (±70 °C). However, how to design ideal TRWSEs efficiently and decipher their evolution at different temperatures is still a great challenge. Herein, via a data-driven strategy, a TRWSE with a melting point as low as -136 °C was elaborately designed. More importantly, the evolution of the TRWSE from intrinsic solvation structures to interphase constructions and to lithium-metal deposition at different temperatures was investigated. Intriguingly, the anion-rich solvation structures in this TRWSE, the anion-derived electrolyte-electrode interphases, and deposited lithium are all temperature-insensitive, especially at low temperatures. Consequently, lithium dendrites are effectively suppressed even at -30 °C with a high Coulombic efficiency of 98.2%. NCM811||Li cells exhibit highly enhanced cycling stability with a capacity retention of almost 100% after 300 cycles at -30 °C. Moreover, 8.5 Ah pouch cells, with a high energy density of 507 Wh kg^-1 and an ultrawide operating temperature of 140 °C, still deliver a capacity retention of 92.3% at temperatures as low as -70 °C, which can discharge even at -110 °C, demonstrating their huge potential at ultralow temperatures.

Low-cost rechargeable sodium-based batteries are regarded as ideal alternatives to replace or complement current lithium-ion batteries in large-scale energy storage applications. Unfortunately, the commercial implementation of sodium-based batteries is restricted by their unsatisfied energy density, severe initial capacity decay, and discontented cycle life. Presodiation techniques including anode pretreatment and cathode additives are widely suggested to alleviate the above problems by providing an extra sodium resource to compensate for the initial capacity loss. However, none of them have been applied at the industrial level due to poor kinetics and severe gas evolution. Hence, in this timely review, we reclassify the presodiation techniques based on their operating locations and charge compensation mechanisms, which could provide intuitive perspectives for practical assessment. Key evaluation factors including kinetic performance, gas evolution behavior, environmental stability, and cost are proposed and systematically analyzed. The corresponding optimization strategies and potential applications are provided, followed by the scientific and technical challenges and suggestions for future industrialization. We believe this review will promote the industrial development of presodiation techniques in the future.

Due to the inherent redox potential of the zinc metal anode (ZMA), it is susceptible to corrosion and dendrite formation in aqueous electrolytes. These issues compromise the electroplating-stripping process at the electrolyte-electrode interface, adversely affecting the reversibility of aqueous zinc-ion batteries (AZIBs). Here, we propose a chelating-ligand additive (i.e., DS) strategy to construct in situ an inorganic/organic hybrid bilayer interface. The organic molecule enriched in -PO₃ groups is calculated to preferentially adsorb onto the surface of ZMA. During subsequent reactions, these adsorbed molecules decompose preferentially due to their low lowest unoccupied molecular orbital energy level (0.34 eV), forming a Zn(PO₃)₂-enriched inorganic solid electrolyte interphase (SEI) layer. Simultaneously, the intermediate carbon skeleton cross-links, creating an organic layer atop the SEI, thereby forming an inorganic/organic hybrid SEI bilayer interface. This bilayer SEI interface effectively inhibits corrosion and hydrogen evolution reactions (HERs) while regulating the Zn²⁺ ion flux at the interface, inducing uniform Zn depositions. Consequently, the Zn||Zn symmetric battery demonstrates a long-term cycling lifespan exceeding 1700 h at 5 mA cm^-2. The Zn||I₂ pouch battery yielded a capacity retention of 71.3% after 1100 cycles. This synergistic modulation strategy offers insights into the development of ZMA stabilizer additives, potentially advancing the performance and durability of AZIBs.

Aqueous zinc (Zn) metal batteries (ZMBs) have received great attention due to their safety and environmental friendliness. Although aqueous electrolytes facilitate fast kinetics in metal oxide cathodes, their incompatibility with the Zn metal anodes triggers severe hydrogen evolution reaction (HER) and dendrite growth. Herein, a self-phase separated electrolyte (SPSE) is proposed to fulfill the contradictory requirements of the anode and cathode in ZMBs. Molecular modeling and experimental investigations verify that the hydrophobic fluorinated solvent with moderate dielectric constant and large Hildebrand parameter disparity relative to water contributes to a spontaneous aqueous-nonaqueous phase separation within the SPSE against stirring and aging. In the as-developed SPSE, the anode nonaqueous phase effectively inhibits the HER and dendrite formation by a synergistic effect of regulated Zn deposition and protective solid electrolyte interphase (SEI). Meanwhile, the aqueous phase in the cathode ensures fast ion insertion/extraction dynamics. Consequently, the SPSE allows for Zn||Zn symmetrical cells with 2500 h cycle life and ultralow corrosion current (0.08 mA cm^-2). Notably, the Zn|SPSE|V₂O₅ full cell sustains over 3000 cycles with negligible HER and corrosion, and the pouch cell demonstrates remarkable operation stability against repeated rollover. Our electrolyte design concept paves a promising path for practical ZMBs that combine long-term cyclability, enhanced safety, and durability.

The renewable energy industry demands rechargeable batteries that can be manufactured at low cost using abundant resources while offering high energy density, good safety, wide operating temperature windows, and long lifespans. Utilizing fluorine chemistry to redesign battery configurations/components is considered a critical strategy to fulfill these requirements due to the natural abundance, robust bond strength, and extraordinary electronegativity of fluorine and the high free energy of fluoride formation, which enables the fluorinated components with cost effectiveness, nonflammability, and intrinsic stability. In particular, fluorinated materials and electrode|electrolyte interphases have been demonstrated to significantly affect reaction reversibility/kinetics, safety, and temperature tolerance of rechargeable batteries. However, the underlining principles governing material design and the mechanistic insights of interphases at the atomic level have been largely overlooked. This review covers a wide range of topics from the exploration of fluorine-containing electrodes, fluorinated electrolyte constituents, and other fluorinated battery components for metal-ion shuttle batteries to constructing fluoride-ion batteries, dual-ion batteries, and other new chemistries. In doing so, this review aims to provide a comprehensive understanding of the structure–property interactions, the features of fluorinated interphases, and cutting-edge techniques for elucidating the role of fluorine chemistry in rechargeable batteries. Further, we present current challenges and promising strategies for employing fluorine chemistry, aiming to advance the electrochemical performance, wide temperature operation, and safety attributes of rechargeable batteries.

A numerical method has been used to analyze the flow field related to a NACA 0015 airfoil with and without a flap and assess the influence of the flap height and angle on the surface pressure coefficient, lift coefficient, and drag coefficient. The numerical results demonstrate that the flap can effectively improve the lift coefficient of the airfoil; however, at small attack angles, its influence is significantly reduced. When the angle of attack exceeds the critical stall angle and the flap height is 1.5% of the chord length, the influence of the flap becomes very evident. As the flap height increases, the starting point of the separation vortex gradually moves forward and generates a larger wake vortex. Optimal aerodynamic characteristics are obtained for 1.5% (of the chord length) flap height and a 45° flap angle; in this case, the separation vortex is effectively reduced.