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[Display omitted] • A firm and dense SEI layer which can effectively suppress corrosion and hydrogen evolution is successfully in situ constructed on the zinc anode without using organic additive. • The inevitable passivation byproducts are utilized and transformed into the dense in-situ SEI protection layer with superior stability and excellent wettability. • A dynamic electrostatic shielding layer is formed on the uneven and sharp locations of the zinc anode by Y3+ which endows the static in-situ SEI layer with dynamic self-repairing function. The practical application of aqueous Zn-ion batteries (AZIBs) is significantly hindered by the short lifespan and low utilization of zinc metal anodes caused by the notorious hydrogen evolution reaction (HER), corrosion, and dendritic growth. The in-situ formation of a dense Zn-ion conducting solid electrolyte interphase (SEI) is an ideal approach to handle these problems. Herein, we present a twofold-protective strategy involving the dense in-situ SEI layer and the electrostatic shielding layer by incorporating 0.01 M yttrium nitrate (YN) additive into 2 M zinc sulfate electrolyte. The robust oxidizing characteristic of the nitrate induces rapid passivation on the surface of Zn anodes, by which these inevitable passivation byproducts are utilized for in-situ fabricating a dense SEI protection layer with excellent wettability. Besides, the infusion of high-valence rare-earth Y3+ forms a durable, dynamic electrostatic shielding layer around the growth tip of the protuberances. This can regulate Zn2+ deposition and aid in rectifying the irregular and sharp surface on zinc anodes. Benefiting from the synergistic effect of the static film protection and the dynamic electrostatic rectification, zinc anodes exhibit outstanding stability, as evidenced by remarkable cycling lifespan of exceeding 2000 h at 1 mAh cm−2 and 600 h at 10 mAh cm−2 in Zn symmetric cells and the preeminent CE of 99.83 % with stably cycling over 2200 times in half-cells at 4 mA cm−2. This study reveals a straightforward yet pragmatic avenue of synergistic dual-protection effect to achieve anti-corrosion and dendrite-free Zn anodes. [ABSTRACT FROM AUTHOR]

[Display omitted] • VO 2 (B), VO 2 (M), and VO 2 (A) are synthesized and their properties are investigated. • ZnSO 4 -based aqueous electrolyte with various concentrations of LiTFSI is developed. • Solvation structures of electrolytes are studied using wide-angle X-ray scattering. • The correlation between solution structures and electrolyte properties is examined. • Operando TXM observations confirm high dimensional stability of VO 2 during cycling. Three VO 2 polymorphs, namely monoclinic VO 2 (B), monoclinic VO 2 (M), and tetragonal VO 2 (A), are synthesized, and their microstructures and electrochemical properties are studied for application in Zn-ion batteries (ZIBs). A cost-effective ZnSO 4 -based aqueous electrolyte with various concentrations (3 − 7 m) of lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) additive is developed. The optimal ZnSO 4 /LiTFSI ratio in the electrolyte for superior Zn//VO 2 battery properties is examined. The coordination structures of various electrolytes are investigated using wide-angle X-ray scattering. The incorporation of LiTFSI impairs the hydrogen-bonded network of H 2 O molecules and causes solvated-TFSI and TFSI‧‧‧TFSI structures to form, altering the electrolyte properties (such as electrochemical stability window, ionic conductivity, and Zn(OH) 2) 3 (ZnSO 4)· x H 2 O byproduct formation tendency). It is found that an excessive LiTFSI concentration leads to the formation of ion aggregates in the electrolyte and thus deterioration of electrode specific capacity and rate capability. Operando transmission X-ray microscopy observations confirm the high dimensional stability of the VO 2 cathode during charging and discharging; the length variation of the VO 2 (B) rods is approximately 10 %. The electrolyte composition also affects the Zn2+/Zn redox behavior at the anode side. The incorporation of LiTFSI into the electrolyte affects the Zn plating/stripping Coulombic efficiency, morphology of the deposited Zn, dead Zn amount, and anode cycle life. The constructed Zn//VO 2 (B) cell with 1 m ZnSO 4 /5 m LiTFSI dual-salt electrolyte shows 90 % capacity retention after 1000 cycles. The proposed electrode material and electrolyte composition have great potential for applications in high-performance and high-stability rechargeable ZIBs. [ABSTRACT FROM AUTHOR]

High-concentration KFSI EC/DEC electrolyte enables great rate performance of graphite anode and KMO cathode. The electrolyte constructs a unique anion-solvent co-derived SEI. [Display omitted] • High-concentration KFSI EC/DEC electrolyte enables great rate performance of KMO and graphite. • The electrolyte constructs a unique anion-solvent co-derived SEI. • The reconstructed cell tests demonstrate the importance of solvation structure and SEI to the rate performance of graphite anode. The system of layered-metal-oxide||carbon-anode cells with carbonate electrolytes is highly promising for constructing potassium-ion batteries (PIBs). However, this system faces serious issues of poor compatibility between the electrolyte and electrode, particularly with conventional ethylene carbonate (EC)-based electrolytes. Herein, owing to the regulated coordination environment of cation–anion-solvent and the formed KF-rich interface, a superior rate performance of graphite anode was achieved. The designed 4 M KFSI EC/DEC electrolyte demonstrates superior performance in graphite||K cells, exhibiting a high reversible capacity of approximately 200 mAh g−1 at a high current density of 700 mA g−1, surpassing many reported high-concentration and weak solvation PIB electrolytes. Meanwhile, it exhibits low polarization and maintains stable contact stability with active K metal. Furthermore, it demonstrates great compatibility with Mn-based layered metal oxide cathodes. Remarkably, we reveal a unique formation mechanism of the solvent-anion co-derived solid electrolyte interface (SEI) through a two-stage XPS deep analysis, which has the KF-deficient inorganic inner and KF-rich outer. This SEI can protect the graphite structure and enable great rate performance of graphite anode. This work holds significant reference value for the design of commercial electrolytes. [ABSTRACT FROM AUTHOR]

[Display omitted] By introducing a minute quantity of phytate ammonium into the conventional dilute zinc sulfate electrolyte, a static physical barrier is established by the phytic anion. Simultaneously, a dynamic electrostatic shield layer collaborates, yielding superior electrochemical performance. This addition facilitates an accelerated de-solvation process, effectively suppressing the so-called "tip effect" and mitigating dendrite growth. • Developed facile and effective additives for aqueous zinc-ion batteries. • Utilized both cation and anion for a multi-functional additive. • Physical barrier and dynamic electrostatic-field shield layer enhance performance. • Realized a dual protection mechanism for high performance. Corrosion and the formation of by-products resulting from parasitic side reactions, as well as random dendrite growth, pose significant challenges for aqueous zinc-ion batteries (AZIBs). In this study, phytate ammonium is introduced into the traditional dilute Zinc sulfate electrolyte as a multi-functional additive. Leveraging the inherent zincophilic nature of the phytic anion, a protective layer is formed on the surface of the zinc anode. This layer can effectively manipulate the deposition process, mitigate parasitic reactions, and reduce the accumulation of detrimental by-products. Additionally, the competitive deposition between dissociated ammonium ions and Zn2+ promotes uniform deposition, thereby alleviating dendrite growth. Consequently, the modified electrolyte with a lower volume addition exhibits superior performance. The zinc symmetric battery demonstrates much more reversible plating/stripping, sustaining over 2000 h at 5 mA cm−2 and 1 mA h cm−2. A high average deposition/stripping efficiency of 99.83 % is achieved, indicating the significant boosting effect and practical potential of our strategy for high-performance aqueous zinc-ion batteries. [ABSTRACT FROM AUTHOR]

• The challenges of LSBs were described at low temperatures. • Strategies to improve low-temperature electrolytes performance were proposed. • Future research directions for LSBs in terms of low-temperature electrolyte design were proposed. The currently used lithium-ion batteries are facing two challenges of insufficient energy density for recharge mileage requirement of electric vehicles and low performance at sub-zero temperatures. Lithium-sulfur batteries (LSBs) with high theoretical energy density may be the next generation of lithium-based batteries. However, LSBs still have their challenges at low temperatures, including accumulation of lithium polysulfide, nucleation of lithium sulfide, lithium deposition, and formation of solid electrolyte interphase film, solvation degree and so on. Electrolytes of LSBs are partially responsible for these issues. To facilitate further research and development of LSBs particularly operated at sub-zero temperatures, this paper reviews the electrolytes of LSBs in terms of electrolyte materials, characterization, functional mechanisms, and performance optimization. The recent advances in electrolyte design strategies, including solvent optimization, lithium salt modification, additive introduction, and solid-state electrolytes of LSBs are emphasized. The challenges of both liquid and solid electrolytes at low temperatures are analyzed and the research directions for overcoming the challenges are also proposed in this paper for further research and development toward practical application. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ether-chain pyrrolidinium and asymmetric imide enables a high Li+ fraction in IL electrolyte. • This electrolyte is first used for a Si/CNT/G||NCM-811 full cell. • Robust LiF- and Li 3 N-rich SEI has balanced organic/inorganic components is crucial. • The long-existing rate capability problem of IL electrolyte has been overcome. • The electrolyte suppresses the interfacial exothermic reactions of delithiated NCM-811. In this study, Si nanoparticles with interweaving carbon nanotubes are wrapped by graphitic sheets to achieve high conductivity and high dimensional stability of a composite anode (denoted as Si/CNT/G) for Li-ion batteries. In addition, an ionic liquid (IL) electrolyte that consists of ether-side-chain pyrrolidinium, asymmetric imide, and a high Li+ fraction is prepared. This electrolyte is for the first time employed for Si-based Li-ion batteries. Decomposition of the ether groups creates organic components in the solid electrolyte interphase (SEI). The high Li+ concentration promotes decomposition of the (fluorosulfonyl)(trifluoromethanesulfonyl)imide (FTFSI−) anions, leading to a LiF- and Li 3 N-rich SEI. The organic-inorganic balanced SEI is responsible for the excellent charge-discharge properties of the Si/CNT/G anode. The FTFSI− anions exhibit low corrosivity toward the Al current collector and high compatibility with the LiNi 0.8 Co 0.1 Mn 0.1 O 2 (NCM-811) cathode. With a charging voltage of 4.5 V, remarkable reversible capacities and cycling stability of NCM-811 in the high-Li+-fraction N -methoxyethyl- N -methylpyrrolidinium/FTFSI IL electrolyte are observed. Differential scanning calorimetry is used to examine the interfacial exothermic reactions between the delithiated NCM-811 and various electrolytes. After 300 charge-discharge cycles, the capacity retention of a Si/CNT/G||NCM-811 full cell with the proposed IL electrolyte is 80% with a Coulombic efficiency of ∼99.9%. These values are significantly higher than those of the conventional carbonate electrolyte cell. [ABSTRACT FROM AUTHOR]

[Display omitted] • A FSI-based IL electrolyte for high-voltage LiNi 0.5 Mn 1.5 O 4 cathode is proposed. • Three electrolyte design strategies are implemented to improve FSI-based IL. • The Li+, FSI−, and TFSI− fractions in IL electrolyte are modulated and optimized. • Our electrolyte design takes into account the graphite anode compatibility. • 5-V graphite//LiNi 0.5 Mn 1.5 O 4 full cell with great performance is demonstrated. Ionic liquids (ILs), with wide electrochemical stability window, high thermal stability, and nonvolatility, are promising electrolytes for lithium-ion batteries. Among ILs with various types of anion, bis(fluorosulfonyl)imide (FSI−)-based ILs are particularly appealing owing to their high ionic conductivity, low viscosity, and great anode compatibility. However, strong corrosivity of FSI− toward the Al current collector at high potential restricts their practical utilization. In this study, three strategies are implemented to overcome this limitation. Li+ fraction modulation, FSI−/bis(trifluoromethyl)sulfonylimide (TFSI−) molar ratio optimization, and their synergistic combination are used to achieve optimal charge–discharge of a high-voltage LiNi 0.5 Mn 1.5 O 4 (LNMO) cathode with an Al substrate. The effects of the IL composition on the electrochemical properties of a graphite anode are also investigated. The proposed IL electrolyte, which lacks any organic solvents, has an optimal Li+/FSI−/TFSI− molar ratio and thus can effectively suppress the Al corrosion, allowing a 5-V graphite//LNMO full cell to be realized. A reversible capacity of ~ 135 mAh g−1 (based on LNMO) and a capacity retention of ~ 85% after 200 cycles are found for the full cell. This study opens a new route for FSI−-based IL electrolytes in the field of high-voltage and high-safety lithium-ion battery applications. [ABSTRACT FROM AUTHOR]