Extended Battery Compatibility Consideration from an Electrolyte Perspective.

The performance of electrochemical batteries is intricately tied to the physicochemical environments established by their employed electrolytes. Traditional battery designs utilizing a single electrolyte often impose identical anodic and cathodic redox conditions, limiting the ability to optimize redox environments for both anode and cathode materials. Consequently, advancements in electrolyte technologies are pivotal for addressing these challenges and fostering the development of next-generation high-performance electrochemical batteries. This review categorizes perspectives on electrolyte technology into three key areas: additives engineering, comprehensive component analysis encompassing solvents and solutes, and the effects of concentration. By summarizing significant studies, the efficacy of electrolyte engineering is highlighted, and the review advocates for further exploration of optimized component combinations. This review primarily focuses on liquid electrolyte technologies, briefly touching upon solid-state electrolytes due to the former greater vulnerability to electrode and electrolyte interfacial effects. The ultimate goal is to generate increased awareness within the battery community regarding the holistic improvement of battery components through optimized combinations.

A Comprehensive Evaluation of Battery Technologies for High-Energy Aqueous Batteries.

Aqueous batteries have garnered significant attention in recent years as a viable alternative to lithium-ion batteries for energy storage, owing to their inherent safety, cost-effectiveness, and environmental sustainability. This study offers a comprehensive review of recent advancements, persistent challenges, and the prospects of aqueous batteries, with a primary focus on energy density compensation of various battery engineering technologies. Additionally, cutting-edge high-energy aqueous battery designs are emphasized as a reference for future endeavors in the pursuit of high-energy storage solutions. Finally, a dual-compatibility battery configuration perspective aimed at concurrently optimizing cycle stability, redox potential, capacity utilization for both anode and cathode materials, as well as the selection of potential electrode candidates, is proposed with the ultimate goal of achieving cell-level energy densities exceeding 400 Wh kg-1.

A Separator with Double Coatings of Li4 Ti5 O12 and Conductive Carbon for Li-S Battery of Good Electrochemical Performance.

The market demand for energy pushes researchers to pay a lot of attention to Li-S batteries. However, the 'shuttle effect', the corrosion of lithium anodes, and the formation of lithium dendrites make the poor cycling performances (especially under high current densities and high sulfur loading) of Li-S batteries, which limit their commercial applications. Here, a separator is prepared and modified with Super P and LTO (abbreviation SPLTOPD) through a simple coating method. The LTO can improve the transport ability of Li+ cations, and the Super P can reduce the charge transfer resistance. The prepared SPLTOPD can effectively barrier the pass-through of polysulfides, catalyze the reactions of polysulfides into S2- , and increase the ionic conductivity of the Li-S batteries. The SPLTOPD can also prevent the aggregation of insulating sulfur species on the surface of the cathode. The assembled Li-S batteries with the SPLTOPD can cycle 870 cycles at 5 C with the capacity attenuation of 0.066% per cycle. When the sulfur loading is up to 7.6 mg cm-2 , the specific discharge capacity at 0.2 C can reach 839 mAh g-1 , and the surface of lithium anode after 100 cycles does not show the existence lithium dendrites or a corrosion layer. This work provides an effective way for the preparation of commercial separators for Li-S batteries.

In situ space-confined growth of Co3O4 nanoparticles inside N-doped hollow porous carbon nanospheres as bifunctional oxygen electrocatalysts for high-performance rechargeable zinc-air batteries.

Developing high-performance and low-cost bifunctional oxygen electrocatalysts for both the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER) is of great significance for accelerating the commercialization of rechargeable zinc-air batteries (RZABs). Herein, in situ grown Co3O4 nanoparticle-embedded N-doped hollow porous carbon nanospheres (Co3O4@N-HPCNs) are synthesized via template-assisted pyrolysis as efficient bifunctional ORR/OER electrocatalysts. The N-HPCNs efficiently seize and confine Co3O4 nanoparticles to enhance electronic conductivity and structural stability, while the hollow porous architecture offers adequate mass diffusion pathways to improve the accessibility of reactants and electrolytes on active sites. Therefore, the as-obtained Co3O4-10%@N-HPCNs display outstanding activity and stability for the ORR and the OER, even outperforming commercial Pt/C and Ru/C catalysts. Liquid RZABs assembled with Co3O4-10%@N-HPCN cathodes exhibit a large specific capacity of 768.3 mA h g-1Zn, a high peak power density of 145.6 mW cm-2 and a long-term cycling stability for over 1000 h, demonstrating much-enhanced battery performance in comparison with that of Pt/C + Ru/C based RZABs. Also, flexible quasi-solid-state RZABs assembled with Co3O4-10%@N-HPCN cathodes exhibit a considerable power density of 132.0 mW cm-2 and a stable charge-discharge voltage for a long period even upon bending. This work provides a new approach for the development of catalysts with high activity, long-term stability and low cost.

Limiting Performance of the Ejector Refrigeration Cycle with Pure Working Fluids.

An ejector refrigeration system is a promising heat-driven refrigeration technology for energy consumption. The ideal cycle of an ejector refrigeration cycle (ERC) is a compound cycle with an inverse Carnot cycle driven by a Carnot cycle. The coefficient of performance (COP) of this ideal cycle represents the theoretical upper bound of ERC, and it does not contain any information about the properties of working fluids, which is a key cause of the large energy efficiency gap between the actual cycle and the ideal cycle. In this paper, the limiting COP and thermodynamics perfection of subcritical ERC is derived to evaluate the ERC efficiency limit under the constraint of pure working fluids. 15 pure fluids are employed to demonstrate the effects of working fluids on limiting COP and limiting thermodynamics perfection. The limiting COP is expressed as the function of the working fluid thermophysical parameters and the operating temperatures. The thermophysical parameters are the specific entropy increase in the generating process and the slope of the saturated liquid, and the limiting COP increases with these two parameters. The result shows R152a, R141b, and R123 have the best performance, and the limiting thermodynamic perfections at the referenced state are 86.8%, 84.90%, and 83.67%, respectively.

RuO2-Incorporated Co3O4 Nanoneedles Grown on Carbon Cloth as Binder-Free Integrated Cathodes for Tuning Favorable Li2O2 Formation.

Developing ideal Li-O2 batteries (LOBs) requires the discharge product to have a large quantity, have large contact area with the cathode, and not passivate the porous surface after discharge, which put forward high requirement for the design of cathodes. Herein, combining the rational structural design and high activity catalyst selection, minor amounts of RuO2-incorporated Co3O4 nanoneedles grown on carbon cloth are successfully synthesized as binder-free integrated cathodes for LOBs. With this unique design, plenty of electron-ion-oxygen tri-phase reaction interface is created, the side reaction from carbon is isolated, and oxygen reduction reaction/oxygen evolution reaction (OER) kinetics are significantly facilitated. Upon discharge, film-like Li2O2 is observed growing on the needle surface first and eventually ball-like Li2O2 particles form at each tip of the needle. The cathode surface remains porous after discharge, which is beneficial to the OER and is rare in the previous reports. The battery exhibits a high specific discharge capacity (7.64 mAh cm-2) and a long lifespan (500 h at 0.1 mA cm-2). Even with a high current of 0.3 mA cm-2, the battery achieves a cycling life of 200 h. In addition, punch-type LOBs are fabricated and successfully operated, suggesting that the cathode material can be utilized in ultralight, flexible electronic devices.

Strategies toward anode stabilization in nonaqueous alkali metal-oxygen batteries.

Alkali metal-O2 batteries exhibit ultra-high theoretical energy density which is even on par with fossil energy and are expected to become the next generation energy storage devices. However, to maintain the advantages of high energy density of alkali metal-O2 batteries, the reversibility of alkali metal anodes with high capacity is of vital importance. But the alkali metal anode with high chemical activity often faces a variety of challenges, including various side reactions, dendrite formation and volume expansion. In this highlight, we focus on the challenges faced by alkali metal anodes in alkali metal-O2 batteries and introduce the latest strategies to effectively stabilize the metal anode. Future perspectives are pointed out, which are valuable for the further development of nonaqueous alkaline metal-O2 batteries.

In situ bridging nanotwinned all-solid-state Z-scheme g-C3N4/CdCO3/CdS heterojunction photocatalyst by metal oxide for H2 evolution.

Nanotwin and all-solid-state (ASS) Z-scheme heterojunction engineering are two widely used strategies for improving photocatalytic activity in H2 production. However, both strategies fail to produce a satisfactory effect when used alone due to their own limitations. Hence, combining nanotwin and ASS Z-scheme heterojunction engineering is expected to improve photocatalytic activity effectively. Herein, we report a nanotwinned ASS Z-scheme g-C3N4/CdCO3/CdS (CN/CC/CS) photocatalyst synthesized for the first time by in situ bridging of (CN) and (CS) with a (CC) conductor. The growth and ripening of CN/CC/CS are limited by thiourea (Tu) and CN. CN/CC/CS can improve charge carrier separation and transfer kinetics due to the synergetic advantages of its nanotwin structure, ASS Z-scheme junction, N-Cd chemically bonded interfaces, in situ intimate contact, and hierarchical architecture. The visible-light-driven H2 production rate of CN/CC/CS is 345% of that of CN/CS. This work proposes a new method for rationally designing novel materials with improved photocatalytic activity by combining heterojunction and defect engineering.

Li2 O2 Formation Electrochemistry and Its Influence on Oxygen Reduction/Evolution Reaction Kinetics in Aprotic Li-O2 Batteries.

Aprotic Li-O2 batteries are regarded as the most promising technology to resolve the energy crisis in the near future because of its high theoretical specific energy. The key electrochemistry of a nonaqueous Li-O2 battery highly relies on the formation of Li2 O2 during discharge and its reversible decomposition during charge. The properties of Li2 O2 and its formation mechanisms are of high significance in influencing the battery performance. This review article demonstrates the latest progress in understanding the Li2 O2 electrochemistry and the recent advances in regulating the Li2 O2 growth pathway. The first part of this review elaborates the Li2 O2 formation mechanism and its relationship with the oxygen reduction reaction/oxygen evolution reaction electrochemistry. The following part discusses how the cycling parameters, e.g., current density and discharge depth, influence the Li2 O2 morphology. A comprehensive summary of recent strategies in tailoring Li2 O2 formation including rational design of cathode structure, certain catalyst, and surface engineering is demonstrated. The influence resulted from the electrolyte, e.g., salt, solvent, and some additives on Li2 O2 growth pathway, is finally discussed. Further prospects of the ways in making advanced Li-O2 batteries by control of favorable Li2 O2 formation are highlighted, which are valuable for practical construction of aprotic lithium-oxygen batteries.