Search

For the past few years, a new generation of energy storage systems with large theoretical specific capacity has been urgently needed because of the rapid development of society. Lithium-sulfur (Li-S) batteries are regarded as one of the most promising candidates for novel battery systems, since their resurgence at the end of the 20th century Li-S batteries have attracted ever more attention, attributed to their notably high theoretical energy density of 2600 W h kg -1 , which is almost five times larger than that of commercial lithium-ion batteries (LIBs). One of the determining factors in Li-S batteries is how to design/prepare the sulfur cathode. For the sulfur host, the major technical challenge is avoiding the shuttling effect that is caused by soluble polysulfides during the reaction. In past decades, though the sulfur cathode has developed greatly, there are still some enormous challenges to be conquered, such as low utilization of S, rapid decay of capacity, and poor cycle life. This article spotlights the recent progress and foremost findings in improving the performance of Li-S batteries by employing multifunctional metal phosphides as host materials. The current state of development of the sulfur electrode of Li-S batteries is summarized by emphasizing the relationship between the essential properties of metal phosphide-based hybrid nanomaterials, the chemical reaction with lithium polysulfides and the latter's influence on electrochemical performance. Finally, trends in the development and practical application of Li-S batteries are also pointed out., (© 2021 Wiley-VCH GmbH.)

As concerns about the safety of lithium-ions batteries (LIBs) increases, aqueous zinc-ion batteries (ZIBs) with a lower cost, higher safety, and higher co-efficiency have attracted more and more interest. However, finding suitable cathode materials is still an urgent problem in ZIBs. In recent years, a lot of significant works have been reported, including manganese-based cathodes, vanadium-based cathodes, Prussian blue analog-based materials, and sustainable quinone cathodes. In this review, some typical cathode materials are introduced. The detailed storage mechanisms and methods for improving the reaction kinetics of the zinc ions are summarized. Finally, the issues, challenges, and the research directions are provided., (© 2020 Wiley-VCH GmbH.)

Sodium-ion batteries (SIBs) have attracted much attention due to their abundance, easy accessibility, and low cost. All of these advantages make them potential candidates for large-scale energy storage. The P2-type layered transition-metal oxides (Na x TMO 2 ; TM=Mn, Co, Ni, Ti, Fe, V, Cr, and a mixture of multiple elements) exhibit good Na + ion conductivity and structural stability, which make them an excellent choice for the cathode materials of SIBs. Herein, the structural evolution, anionic redox reaction, some challenges, and recent progress of Na x TMO 2 cathodes for SIBs are reviewed and summarized. Moreover, a detailed understanding of the relationship of chemical components, structures, phase compositions, and electrochemical performance is presented. This Review aims to provide a reference for the development of P2-type layered transition-metal oxide cathode materials for SIBs., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Conventional lithium-ion batteries, with flammable organic liquid electrolytes, have serious safety problems, which greatly limit their application. All-solid-state batteries (ASSBs) have received extensive attention from large-scale energy-storage fields, such as electric vehicles (EVs) and intelligent power grids, due to their benefits in safety, energy density, and thermostability. As the key component of ASSBs, solid electrolytes determine the properties of ASSBs. In past decades, various kinds of solid electrolytes, such as polymers and inorganic electrolytes, have been explored. Among these candidates, organic-inorganic composite solid electrolytes (CSEs) that integrate the advantages of these two different electrolytes have been regarded as promising electrolytes for high-performance ASSBs, and extensive studies have been carried out. Herein, recent progress in organic-inorganic CSEs is summarized in terms of the inorganic component, electrochemical performance, effects of the inorganic ceramic nanostructure, and ionic conducting mechanism. Finally, the main challenges and perspectives of organic-inorganic CSEs are highlighted for future development., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

As anode materials for high-performance Li-ion batteries, peapod-like Ge-based composites, including Ge, a Li-inactive conducting Cu 3 Ge, and a porous carbon matrix are synthesized simply by annealing CuGeO 3 @dopamine in a H 2 /Ar atmosphere. The introduction of the carbon layer and inactive alloying phase Cu 3 Ge not only enhances the electrical conductivity of the Ge anode, but also reduces the volume change of Ge during the cell cycle as a buffer. In particular, the anode of this peapod-like Cu 3 Ge/Ge@C shows an excellent long cycle life as well as outstanding capacity performance, with a discharge specific capacity up to 934 mA h g -1 after 500 cycles., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Amorphous nanoparticles of ZnO and TiO 2 embedded in carbon nanocages (AZT⊂CNCs) were successfully synthesized through a simple annealing process of TiO 2 -coated zeolitic imidazolate framework-8 (ZIF-8). In the current anode of AZT⊂CNCs, tiny ZnO and TiO 2 nanoparticles were uniformly distributed in the carbon matrix (carbon nanocages), which could effectively buffer the volume expansion of electroactive ZnO and provide excellent electric conductivity. After fully investigating the electrochemical performance of the AZT⊂CNCs samples obtained with different additive amounts of tetrabutyl orthotitanate (TBOT) for TiO 2 coating, it has been found that AZT-30 (0.1 g ZIF-8 with 30 mL TBOT) shows the best cycle stability (510 mA h g -1 after 350 cycles at 200 mA g -1 ) and a superior rate capability (610 mA h g -1 after 3500 cycles at 2 A g -1 ). The greatly enhanced Li-ion storage performance could be ascribed to the fact that the introduction of amorphous TiO 2 could activate the reversible lithiation/delithiation reaction of ZnO during the charge/discharge process., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The sulfur cathode, as a new generation of lithium-ion battery cathode material, has a high theoretical energy density of about 2500 Wh kg -1 . However, the low conductivity of sulfur and the "shuttle effect", widely presenting in the lithiation/de-lithiation process, seriously hinder its practical application. Here, we report a new nanoconfined oxidation route (first complete oxidation of metal sulfide and subsequently partial oxidation of the generated S from sulfide) for S cathode encapsulated with MnO 2 nanosheets and N-doped carbon hollow spheres. This nanoconfined oxidation route can successfully confine the sulfur particles in the interior of the carbon shell, and the rationally introduced nonpolar carbon and polar MnO 2 can both reduce the dissolution of polysulfide during the charge-discharge process. The obtained well-defined S-MnO 2 @C cathode exhibits high specific capacity with excellent cycling performance and superior rate capability., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)