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The practical applications of aqueous Zn/I2 batteries (AZIBs) operating within a wide temperature range are severely hindered by the uncontrolled shutting of polyiodide ions (I3−/ I5−) and rampant side reactions. In this study, a wide temperature tolerant polyanionic hydrogel (borax‐bacteria cellulose / p(AMPS‐AM)) with ion selective permeability is designed for inhibiting shutting effect and side reactions under extreme temperatures range from −50 to 50 °C. The zincophilic R−SO3− significantly enhances the transport of Zn2+ cations and promotes uniform growth of Zn metal along the (002) plane. Moreover, the abundant hydrophilic groups in hydrogels effectively suppress both the hydrogen evolution reaction and the formation of by‐products by reducing the water reactivity. Furthermore, theoretical calculations, visualization experiment and in situ Raman spectroscopy confirm that R−SO3− group effectively hinders the shuttle process of I3−/I5− anions through electrostatic repulsion. Consequently, this gel electrolyte facilitates the ultra‐stable Zn/I2 full cell at a low current density of 2 C over a wide temperature range of 100 °C. A Zn/I2 pouch cell with a low negative/positive capacity ratio of 3.3 exhibits a stable performance over 350 cycles with an impressive high‐areal capacity of 2.03 mA h cm−2, thereby establishing a solid foundation for its practical applications. [ABSTRACT FROM AUTHOR]

Sodium‐ion batteries (SIBs) with wide operating temperature are regarded as promising candidates for large‐scale energy storage systems. However, SIBs operating under elevated temperature aggravate the electrolyte decomposition with unstable cathode‐electrolyte interphase (CEI), causing a rapid capacity degradation. Herein, anion receptor tris(pentafluorophenyl)borane (TPFPB) is selected as electrolyte additive to construct robust NaF‐rich CEI. The strong interactions between anion and TPFPB via the electron‐deficient boron atoms weaken ClO4− solvation and promote the coordination capability between solvents and Na+ cations, demonstrating greatly improved oxidative stability. Na3V2(PO4)3 cathode in TPFPB‐containing electrolyte delivers long‐term stability with a capacity retention of 86.9% after 100 cycles at a high cut‐off voltage of 4.2 V (vs. Na+/Na) and a high temperature of 60 °C. Besides, TPFPB also works well with enhanced performance over a temperature range from −30 to 60 °C. This study proposes a prospective method by manipulating the solvation chemistry for constructing high‐temperature rechargeable SIBs. [ABSTRACT FROM AUTHOR]

Carbon with few active sites and narrow interlayer distance as anode for potassium ion batteries (PIBs) always shows low capacity, sluggish kinetics, and low Columbic efficiency. Herein, poly(2‐aminothiazole) (P2AT) hollow nanospheres are first synthesized as a carbon source for high N, S co‐doped carbon hollow nanospheres (NS‐HCSs). The hollow P2AT nanospheres can be controllably synthesized with an Ostwald ripening process. The unique doping and structure endow the NS‐HCSs with high content of N and S dopants in carbon, mesoporous structure with enlarged interlayer distance, elevated ratio of N‐6 and N‐5 species, enhanced conductivity, abundant surface defects, and large active sites. When evaluated as an anode for PIBs, NS‐HCSs exhibit a high reversible capacity of 422 mAh g‒1 and excellent long‐term cycling performance. Using combined experiment and theoretical computation, including in situ TEM and in situ Raman, the K‐storage mechanism and dynamic evolution processes of NS‐HCSs, including low volume expansion, enhanced K‐ion adsorption, and stable composition and structure evolution during repeating potassiation/de‐potassiation processes is revealed. This quantitative design for highly durable K‐storage and large capacity in carbon can be advantageous for the rational design of anode materials of PIBs with ideal electrochemical performance. [ABSTRACT FROM AUTHOR]

Aqueous zinc ion batteries (AZIBs) with high safety, low cost, and eco‐friendliness advantages show great potential in large‐scale energy storage systems. However, their practical application is hindered by low Columbic efficiency and unstable zinc anode resulting from the side reactions and deterioration of zinc dendrites. Herein, tripropylene glycol (TG) is chosen as a dual‐functional organic electrolyte additive to improve the reversibility of AZIBs significantly. Importantly, ab initio molecular dynamics theoretical simulations and experiments such as in situ electrochemical impedance spectroscopy, and synchrotron radiation‐based in situ Fourier transform infrared spectroscopy confirm that TG participates in the solvation sheath of Zn2+, regulating overpotential and inhibiting side reactions; meanwhile, TG inhibits the deterioration of dendrites and modifies the direction of zinc deposition by constructing an adsorbed layer on the zinc anode. Consequently, a Zn‐MnO2 full cell with TG electrolyte exhibited a specific capacity of 124.48 mAh g‐1 after 1000 cycles at a current density of 4 A g‐1. This quantitative regulation for suitable solvation sheath and adsorbed layer on zinc anode, and its easy scalability of the process can be of immediate benefit for the dendrite‐free, high‐performance, and low‐cost energy storage systems. [ABSTRACT FROM AUTHOR]

Among the various semiconductor materials, zinc telluride possesses the lowest electron affinity and ultrafast charge separation capability, facilitating improved charge transfer kinetics. In addition, ZnTe has a relatively high density, contributing to high volumetric capacity. Here, 1D N‐doped carbon‐coated ZnTe core‐shell nanowires (ZnTe@C) are designed and prepared via a facile ion‐exchange and carbonization technique. When evaluated as anode for metal ion batteries, it demonstrates superior electrochemical performance in both Li and Na ion storage, including high gravimetric and volumetric capacities (1119 mA h g−1 and 906 mA h cm−3, respectively, at 100 mA g−1 for Li ion storage), excellent high‐rate capability, and long‐term cycling stability. This remarkable electrochemical performance is attributed to the low electron affinity and high density of ZnTe, and the amorphous nature of the N‐doped carbon layer in the heterostructured ZnTe@C nanowires, which not only provide fast charge transfer paths, but also effectively maintain the structural and electrical integrity of the ZnTe. The strategy of embedding high density and high‐performance active materials in highly conductive nanostructures represents an effective way of achieving electrode materials with excellent gravimetric and volumetric capacities towards superior energy storage systems. [ABSTRACT FROM AUTHOR]

In the work, a facile yet efficient self-sacrifice strategy is smartly developed to scalably fabricate hierarchical mesoporous bi-component-active ZnO/ZnFe2O4 (ZZFO) sub-microcubes (SMCs) by calcination of single-resource Prussian blue analogue of Zn3[Fe(CN)6]2 cubes. The hybrid ZZFO SCMs are homogeneously constructed from well-dispersed nanocrstalline ZnO and ZnFe2O4 (ZFO) subunites at the nanoscale. After selectively etching of ZnO nanodomains from the hybrid, porously assembled ZFO SMCs with integrate architecture are obtained accordingly. When evaluated as anodes for LIBs, both hybrid ZZFO and ZFO samples exhibit appealing electrochemical performance. However, the as-synthesized ZZFO SMCs demonstrate even better electrochemical Li-storage performance, including even larger initial discharge capacity and reversible capacity, higher rate behavior and better cycling performance, particularly at high rates, compared with the single ZFO, which should be attributed to its unique microstructure characteristics and striking synergistic effect between the bi-component-active, well-dispersed ZnO and ZFO nanophases. Of great significance, light is shed upon the insights into the correlation between the electrochemical Li-storage property and the structure/component of the hybrid ZZFO SMCs, thus, it is strongly envisioned that the elegant design concept of the hybrid holds great promise for the efficient synthesis of advanced yet low-cost anodes for next-generation rechargeable Li-ion batteries. [ABSTRACT FROM AUTHOR]

Sodium‐ion batteries (SIBs) are a promising candidate for large‐scale energy storage due to the low cost and abundant sodium resources. However, the formation of sodium dendrites on the surface of hard carbon (HC) anodes is the most intractable challenge for full cells during charging, leading to severe performance degradation and safety hazards. Here, a robust additive‐induced borate and fluoride‐rich interphase is constructed by introducing sodium difluoro(oxalato)borate (NaDFOB) as additive in the ether‐based electrolyte to relieve the performance deterioration for SIBs. NaDFOB can participate in the passivation process of electrolyte‐electrode interfaces through preferential oxidation and reduction of DFOB− to effectively restrain the growth of sodium dendrites. Moreover, the electrolyte decomposition and dissolution of transition metal ions are effectively inhibited. Benefiting from that, FeMn‐based Prussian blue (FeMnHCF) || HC full cell with a negative/positive capacity ratio (N/P ratio) of 1.09 displays a capacity retention of 82.1%, especially with a low N/P ratio of 0.96 the cell still demonstrates a stable Coulombic efficiency of over 99.9% after 500 cycles via using NaDFOB as additive. As a practical demonstration, the designed 18650 full cells display enhanced cycling stability with NaDFOB additive. The findings provide insights into the additive‐induced inorganic‐rich interfacial layers for dendrite‐free SIBs. [ABSTRACT FROM AUTHOR]