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High‐performance and temperature‐resistant lithium‐ion batteries (LIBs), which are able to operate at elevated temperatures (i.e., >60 °C) are highly demanded in various fields, especially in military or aerospace exploration. However, their applications were largely impeded by the poor electrochemical performance and unsatisfying safety issues, which were induced by the severe side reactions between electrolytes and electrodes at high temperatures. Herein, with the synergetic effects of solvation chemistry and functional additive in the elaborately designed weakly solvating electrolyte, a unique robust organic/inorganic hetero‐interphase, composed of gradient F, B‐rich inorganic components and homogeneously distributed Si‐rich organic components, was successfully constructed on both cathodes and anodes, which would effectively inhibit the constant decomposition of electrolytes and dissolution of transition metal ions, thus highly enhancing the high‐temperature electrochemical performance. As a result, both cathodes and anodes, without compromising their low‐temperature performance, can operate at temperatures ≥100 °C, with excellent capacity retentions of 96.1 % after 500 cycles and 93.5 % after ≥200 cycles, respectively, at 80 °C. Ah‐level LiCoO2||graphite full cells with a cut‐off voltage of 4.3 V also exhibited superior temperature‐resistance with a capacity retention of 89.9 % at temperature as high as 120 °C. Moreover, the fully charged pouch cells exhibited highly enhanced safety, demonstrating their potentials in practical applications at ultrahigh temperatures. [ABSTRACT FROM AUTHOR]

Aqueous zinc‐ion batteries (AZIBs) attract attention due to their safety and high specific capacity. However, their practical applications are constrained by Zn anode corrosion, dendritic growth, and poor temperature adaptability induced by a strong hydrogen‐bond network in aqueous electrolytes. Herein, a universal strategy to design strong solvating electrolytes is proposed, in which the hydrogen‐bond network and solvation structures are reconstructed by regulating the dipolar‐dipolar and ion‐dipolar interactions simultaneously. Consequently, the hydrogen‐bond network in free water is largely weakened, and the water content in the Zn2+ solvated sheath is reduced, while the hydrogen‐bond network between solvents is strengthened, which effectively broadens the operating temperature range and suppresses Zn dendrites and corrosion. As a result, Zn anodes exhibit excellent platting/stripping efficiency with an average Coulombic Efficiency up to 99.89% after 2000 cycles at 0.5 mA cm−2, impressive cycling stability (5000 h, 0.5 mA cm−2/0.5 mA h cm−2), and a wide operating temperature range of 140 °C (−50–90 °C). Moreover, the Zn//V2O3 full cells also display enhanced temperature‐resistance, implying that the designed strong solvation electrolyte has practical application potential in extreme environments. This study suggests a promising strategy to design ideal electrolytes for high‐performance AZIBs with safety, ultralong cycling life, and satisfying temperature‐resistance. [ABSTRACT FROM AUTHOR]

Lithium metal batteries (LMBs), due to their ultra‐high energy density, are attracting tremendous attentions. However, their commercial application is severely impeded by poor safety and unsatisfactory cycling stability, which are induced by lithium dendrites, side reactions, and inferior anodic stability. Electrolytes, as the indispensable and necessary components in lithium metal batteries, play a crucial role in regulating the electrochemical performance of LMBs. Recently, the fluorinated electrolytes are widely investigated in high‐performance LMBs. Thus, the design strategies of fluorinated electrolytes are thoroughly summarized, including fluorinated salts, fluorinated solvents, and fluorinated additives in LMBs, and insights of the fluorinated components in suppressing lithium dendrites, improving anodic stability and cycling stability. Finally, an outlook with several design strategies and challenges will be proposed for novel fluorinated electrolytes. [ABSTRACT FROM AUTHOR]

Regulating the distribution of surface elements in lithium‐rich cathode materials can effectively change the electrochemical performance of cathode materials. Considering that the enrichment of Mn element on the surface is the main reason for the irreversible phase transition and dissolution of its surface structure, which in turn is the main reason for performance degradation. Based on the molten salt‐assisted sintering method, a lithium rich cathode material with surface rich Ni and Co is designed and prepared. The surface enrichment of Ni and Co effectively reduces the dissolution of Mn, promotes the occurrence of irreversible collapse of surface structure from layered phase to rock salt phase on the material surface, improves the stability of surface crystal phase structure, and improves the cycling stability of positive electrode materials. Notably, after 500 cycles at 1 C current density, the discharge‐specific capacity attained 189.8 mAh g −1, with a capacity retention rate of 88.9%, indicating a 42.1% improvement in capacity retention. Molten salt treatment is widely used in the modification of positive electrode materials. The research work will provide new ideas for improving the stability of lithium rich materials and promoting their commercial applications. [ABSTRACT FROM AUTHOR]

Crystalline RuSe2 nanoparticles were prepared by a facile hydrothermal approach followed by thermal treatment, and utilized as a pseudocapacitive electrode material for supercapacitors for the first time, which exhibited a specific capacitance of 100.8 F g−1 at 0.2 A g−1 with good rate performance and superior cycle stability. [ABSTRACT FROM AUTHOR]

Crystalline RuSe2 nanoparticles were prepared by a facile hydrothermal approach followed by thermal treatment, and utilized as a pseudocapacitive electrode material for supercapacitors for the first time, which exhibited a specific capacitance of 100.8 F g-1 at 0.2 A g-1 with good rate performance and superior cycle stability.

Carbon quantum dots (CQDs) as novel types of emerging materials have aroused tremendous attention in recent years. Herein, we report for the first time a new application of 3D CQD-based composite aerogels as excellent electrode materials for alkaline aqueous batteries. The scalable graphitic CQDs are prepared with high yields (>40%) and further utilized to fabricate the novel nitrogen-doped CQDs/reduced graphene oxide/porous Fe 2 O 3 (N-CQDs/rGO/Fe 2 O 3 ) composite aerogels with different contents of Fe 2 O 3 . Benefiting from the unique 3D network composite aerogel structure with a high surface area and hierarchical porous structure as well as the synergistic effect of high-capacity Fe 2 O 3 and highly conductive and stable N-CQDs/rGO, the composite aerogels achieve enhanced electrochemical properties with ultrahigh specific capacity, admirable rate property, and superior cycling performance. Furthermore, the N -CQDs/rGO/Fe 2 O 3 -1 electrode (Fe 2 O 3 , 34.9 wt %) exhibits the best rate capability (72.1, 58.9, and 46.2% capacity retention at 5, 50, and 100 A g -1 , respectively) and cycle performance (80.4% capacity retention at 3 A g -1 over 5000 cycles), while the N-CQDs/rGO/Fe 2 O 3 -3 electrode (Fe 2 O 3 , 62.3 wt %) displays the highest specific capacity (274.1 mA h g -1 at 1 A g -1 ). The current research provides a valuable guidance for developing high-performance 3D CQD-based composite aerogels for application in energy storage systems.